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    Journal of East China Normal University(Natural Science) 2018 Vol.2018
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    A free boundary problem in variational inequality with gradient constraint
    GUAN Chong-hu, CHEN Jing
    Journal of East China Normal University(Natural Sc    2018, 2018 (1): 1-10.   DOI: 10.3969/j.issn.1000-5641.2018.01.001
    Abstract490)   HTML13)    PDF (354KB)(540)      
    Consider a parabolic variational inequality with gradient constraint
    min{vt-1/2σ2vxx-μvx+cv,vx-1}=0.
    The problem stems from a stochastic optimal control problem based on optimal dividend model. By using PDE technique and the penalty method, the existence and uniqueness and some a priori estimates of the solution of the variational inequality are obtained, and then the properties of the free boundary are further discussed. It is proved that the free boundary can be expressed as a function of x with respect to t and is a monotonically increasing, C smooth curve starting from zero.
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    Edge-magic even-gracefulness of several kinds of spread network models
    LI Yi-chun, SUN Hui, YAO Bing
    Journal of East China Normal University(Natural Sc    2018, 2018 (1): 11-16,23.   DOI: 10.3969/j.issn.1000-5641.2018.01.002
    Abstract457)   HTML70)    PDF (590KB)(574)      
    We present a new definition, called edge-magic even-graceful labeling in this paper, and then we discover a new algorithm, called firework operation, which can add leaves with edge-magic graceful labeling and edge-magic even-graceful labeling. We spread several kinds of network models based on the complete graph K3 and star trees and so on, and then investigate their edge-magic even-graceful properties. A connection between the edge-magic odd-graceful labeling and the edge-magic even-graceful labeling is obtained which produces network models with edge-magic graceful labeling.
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    Lipschitz-likeness and contingent derivative of an implicit multifunction
    WANG Li-na, FANG Zhi-miao, LI Ming-hua
    Journal of East China Normal University(Natural Sc    2018, 2018 (1): 17-23.   DOI: 10.3969/j.issn.1000-5641.2018.01.003
    Abstract462)   HTML16)    PDF (264KB)(582)      
    In this paper by introducing a key assumption, we prove that the key assumption is equivalent to the Robinson metric regularity of the implicit multifunction and that under some suitable conditions the key assumption is sufficient for the Lipschitz-likeness (metric regularity) of the implicit multifunction. Finally, we establish the specific expressions of the contingent derivative and the second-order contingent derivative for the implicit multifunction.
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    A stability theorem for solutions of general time interval multidimensional BSDEs with uniformly continuous generators
    DONG Yong-peng, WANG Qian-ru, MA Jiao-jiao
    Journal of East China Normal University(Natural Sc    2018, 2018 (1): 24-34,49.   DOI: 10.3969/j.issn.1000-5641.2018.01.004
    Abstract408)   HTML10)    PDF (455KB)(646)      
    The existence and uniqueness of solutions for general time interval multi-dimensional backward stochastic differential equations (BSDEs) was proved in Fan et al. (2015) under assumptions that the generator g satisfies the Osgood condition in y and the uniformly continuous condition in z both non-uniformly with respect to t, and the i-th component gi of g depends only on(w, t, y) and the i-th row of the matrix z. In this paper, by virtue of a uniform approximation of uniformly continuous functions by a sequence of Lipschitz functions, the theorem of Girsanov, and the Bihari inequality, we establish, for the first time, a stability theorem for the solutions of the general time interval multidimensional BSDEs with uniformly continuous generators.
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    The existence of time-dependent attractors for abstract evolution equations with fading memory
    HU Di-di, WANG Xuan
    Journal of East China Normal University(Natural Sc    2018, 2018 (1): 35-49.   DOI: 10.3969/j.issn.1000-5641.2018.01.005
    Abstract442)   HTML18)    PDF (285KB)(648)      
    In this paper, the long-time dynamical behavior of solutions for the abstract evolution equations with fading memory is investigated on time-dependent spaces. By applying the modified pull-back attractors theory, techniques of a priori estimate and operator decomposition, we verify the asymptotic compactness of the process. Furthermore, the existence and regularity of time-dependent global attractors are proved. This paper improves some known results.
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    Meromorphic solutions of some type of system of differential and difference equations
    YANG Yan-yan, WEI Wen-long, HUANG Zhi-gang
    Journal of East China Normal University(Natural Sc    2018, 2018 (1): 50-58.   DOI: 10.3969/j.issn.1000-5641.2018.01.006
    Abstract477)   HTML10)    PDF (270KB)(595)      
    This article investigates some properties of meromorphic solutions of the type of system of differential-difference equations of the following form

    where n ≥ 4,p1(z)、p2(z) are non-zero polynomials, and h1(z),h2(z) are entire functions. By using Nevanlinna theorem, we have obtained the solution of above equation is unique. We also discuss the conditions for several types of system of differential-difference equations if the systems of equations actually pose meromorphic solutions of finite order.
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    The transition and properties from Boolean networks to discrete-time Markov chains: A case study of mice stem cell gene regulatory networks
    LYU Yue, ZHANG Min, QIN Xu-dong, YAN Jia
    Journal of East China Normal University(Natural Sc    2018, 2018 (1): 59-75,90.   DOI: 10.3969/j.issn.1000-5641.2018.01.007
    Abstract498)   HTML10)    PDF (956KB)(578)      
    This paper proposes a new method based on probabilistic model checking technique to solve the problem of detecting attractors in gene regulatory networks which is vital in bio-engineering. We transform a gene regulatory network into a discrete-time Markov chains (DTMC for short) by using truth table. We verify the possibility of gene activation in some "long term" through a model checker named PRISM, which help us to find attractors of the gene regulatory network. In this paper, we show the whole procedure using the example of mice stem cell gene regulatory networks. Meanwhile, we make a new technique of detecting the promotion/inhibition relations between genes by adding gene disturbance and modifying gene activation/suppression probability. We show that in the mice regulatory network, seven genes will remain their invariable states in some "long term", then the rest of "changing" genes forms a cyclic attractor. The experiment shows that our method can find the attractors easily and directly. Moreover, our experiment successfully finds those genes affected by gene Gata1, which would be helpful for studying the mice leucopenia.
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    Data cleaning on probabilistic RDF database
    WANG Zhen, LIN Xin
    Journal of East China Normal University(Natural Sc    2018, 2018 (1): 76-90.   DOI: 10.3969/j.issn.1000-5641.2018.01.008
    Abstract333)   HTML10)    PDF (702KB)(541)      
    Due to the factors such as errors and noises in the process of obtaining and analyzing data, uncertain data arises in many domains, which has emerged as an important issue affecting the performance of data. Uncertain data can be stored in probabilistic databases and query facilities always yield answers with confidence. However, the accumulation and propagation of uncertainty may reduce the usability of the query results. As such, it is desirable to reduce the uncertainty of uncertain data. This paper aims at solving the problem how to promote the answers' certainty in RDF(resource description framework) graph query via crowdsourcing. The basic idea is to ask the crowd to decide whether the relationships represented by some edges are correct. In this paper, we introduce three different algorithms to select the edge which maximizes the uncertainty reduction. Finally, we verify these algorithms by experiments and show that unstable pruning algorithm and stable pruning algorithm perform better in term of efficiency.
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    Forward stagewise additive modeling for entity ranking in documents
    WANG Yan-hua
    Journal of East China Normal University(Natural Sc    2018, 2018 (1): 91-102,145.   DOI: 10.3969/j.issn.1000-5641.2018.01.009
    Abstract475)   HTML11)    PDF (576KB)(604)      
    Key entities of a document can help to summarize the subjects of the events or the topics that the document describes, which can contribute to applications such as entity-oriented information retrieval and question-answering. However, entities in free text are unordered and hence it is important to rank entities of a document. In this paper, firstly, we make full use of features of entities that extracted from the document and draw support from Wikipedia and Word Embedding to generate external features. Then, we propose a novel ranking model named LA-FSAM(FSAM based on AUC Metric and Logistic Function) which is based on forward stagewise algorithm additive modeling. In LA-FSAM, we employ the AUC(Area Under the Curve) metric to construct the loss function and the logistic function to integrate features of entities. Finally, the stochastic gradient descent is utilized to optimize parameters of LA-FSAM model. After experiments, our evaluation shows the efficiency of the model we proposed.
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    IM2: Improved MIN/MAX window functions optimizer in relational database
    SONG Guang-xuan, ZHAO Da-peng, WANG Xiao-ling
    Journal of East China Normal University(Natural Sc    2018, 2018 (1): 103-116.   DOI: 10.3969/j.issn.1000-5641.2018.01.010
    Abstract513)   HTML10)    PDF (700KB)(653)      
    Window functions, also known as analytic OLAP functions, is a part of the SQL standard, and has been extensively studied during the past decade. And the window function has more and more extensive application prospects withthegrowthofthedemandstheanalyticalapplications. Despite its simple syntax, window functions can express many complex queries, such as ranking, moving average, cumulative sum and so on. Although almost all the current mainstream commercial database support window function, the existing implementation strategy is inefficient, and is not suitable for processing big data. In this paper, we propose the IM2 algorithm, an improved algorithm for the MAX/MIN window functions, which effectively improves the efficiency. And we prove the effectiveness of the IM2 algorithm the theoretical complexity analysis. Additionally, we implement the algorithm in PostgreSQL and conduct extensive experiments on real world data to demonstrate the efficiency of the IM2 algorithm.
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    Study on the near-field effect of spherical composite antenna arrays in the radio frequency simulation system
    CHENG Bo, ZHU Shou-zheng, FU Lu, BIAN Jia-jun, YU Ting-xiang, ZHU Wei-hua, WANG Li-quan, PANG Xu-dong, ZHANG Yu, LIU Chao-jie
    Journal of East China Normal University(Natural Sc    2018, 2018 (1): 117-127.   DOI: 10.3969/j.issn.1000-5641.2018.01.011
    Abstract459)   HTML9)    PDF (731KB)(663)      
    The angular accuracy of target signal is affected by the near-field effect in the radio frequency composite array. This paper presents a new method to solve the problem. The radiation electric field distribution of a three-element sub-array located on the spherical composite antenna arrays at the receiving antenna location, which is usually located in the radiating near-field region, is precisely calculated by an hybrid technique of the full-wave algorithm and uniform geometrical theory of diffraction (UTD), in the case of the three-element array surrounded with its nearby elements working at same and different frequencies. The equivalent phase center of the three-element array is then obtained by the phase gradient algorithm (PGA) based on its phase distribution. The deviation of the equivalent phase center with that derives from the amplitude gravity center equation is calculated, which is used to find the corrected input power for each element antenna of the three-element array. The simulation results for a real composite antenna array system show that the maximum angular accuracy of pitching direction is corrected from 1.50/2.37 milliradian to 0.06/0.06 milliradian on the microwave three-element antenna and millimeter wave three-element antenna.
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    Beam automatic detection wire scanner system design
    SHAO Zhong-wei, HAN Ding-ding, GONG Pei-rong
    Journal of East China Normal University(Natural Sc    2018, 2018 (1): 128-134,145.   DOI: 10.3969/j.issn.1000-5641.2018.01.012
    Abstract395)   HTML8)    PDF (841KB)(546)      
    A beam automatic detection wire scanner system was developed to improve the measurement resolution and shorten the data processing time. The system managed the sampling process by multi-process priority mechanism, using Allen function to amplify signal variation characterization after signal processing. Fitting range was recognized based on short time average/long time average and Akaike information criterion, and fitting parameter initial values were determined by energy gradient curve. It is found that the system detects beam accurately and improves the measurement resolution and shortens data processing time.
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    CFAR target detection algorithm based on dual-censoring threshold in non-homogeneous environments
    LIU Gui-ru, WANG Lu-lin, ZOU Shan
    Journal of East China Normal University(Natural Sc    2018, 2018 (1): 135-145.   DOI: 10.3969/j.issn.1000-5641.2018.01.013
    Abstract502)   HTML60)    PDF (692KB)(729)      
    In order to solve the problem that the detection performance of the radar target detector decreases badly in non-homogeneous environments. Based on the actual echo clutter distribution, a dual-censoring threshold constant false alarm rate (DCT-CFAR) detector is proposed. Dual censoring threshold is used to remove the large and small unwanted samples and real-time accurate estimate the background noise power level. Compared with the simulation and analysis results of other detectors, the proposed detector has the best detection performance and stability in multi-interfering targets, masking effect, clutter edge and other non-homogenous environments. The results show that the proposed detector still has a good detection performance in non-homogeneous environments.
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    Analysis of characteristics of the cold water patch off the Jiangsu coast in summer 2016
    HE Zhan-yuan, ZHANG Wen-jing, ZHU Shou-xian, CHEN Yang, ZHENG Hou-jun
    Journal of East China Normal University(Natural Sc    2018, 2018 (1): 146-153,170.   DOI: 10.3969/j.issn.1000-5641.2018.01.014
    Abstract443)   HTML8)    PDF (728KB)(628)      
    In this paper, the analysis of characteristics of a cold water patch (CWP) off the Jiangsu coast is carried out based on in-situ oceanographic observations using CTD and remote sensing data made by the Advanced Very High Resolution Radiometer (AVHRR)in the period of summer 2016 from June to Augst. Analysis of the CTD data demonstrates that relatively cold waters occurred at different depths from the sea surface to 30 m over the study region in summer 2016, with the center of the cold waters leaning to the east at deeper depth. This confirms the transportation of cold subsurface waters from the bottom of the Yellow Sea to the Jiangsu coast. The distributions of monthly averaged AVHRR Sea Surface Temperature (SST) demonstrate the existence of CWP, the radius of which varies from 67.9 km to 85.8 km, the intensity from 0.5℃ to 1.2℃, the temperature difference between the CWP center and the coast at the same latitude from 1.9℃ to 2.9℃. The daily distribution of SST indicates that there are 78 days existing CWP, among which the maximum radius is 161.8 km, the maximum intensity is 2.8℃, the maximum temperature difference is 5.9℃. The daily position of CWP center ranges in a large area, the longest distance between two adjacent days is 125.4 km. The effect of the surface wind forcing on the cold water area is also examined using a correlation analysis of the estimated radius and intensity of the CWP with surface winds, which came to a conclusion the southerly wind plays an important role in developing the CWP.
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    Geomorphic characteristics of the Siming Mountain (Zhejiang, China) based on ASTER-GDEM data analysis
    XU Rui, DAI Xue-rong, SHI Yu-xin, ZHENG Li-bo, HE Shan-shan
    Journal of East China Normal University(Natural Sc    2018, 2018 (1): 154-162.   DOI: 10.3969/j.issn.1000-5641.2018.01.015
    Abstract591)   HTML9)    PDF (3017KB)(608)      
    Based on ASTER-GDEM data, the geomorphic characteristics of the Siming Mountain (Zhejiang, China) are analyzed using ArcGIS. Parameters describing local relief, the Swath profile and Hypsometric Integral (HI) are applied. The results show that the Siming Mountain of NE-SW is controlled by fault structures. Area occupied by mid-elevation mountain, low-elevation mountain, hill and foothill is 0.6%, 16.2%, 32.7%, and 50.5% respectively; the mid-and low-elevation mountain have a low amplitude of relief (about 81 m). Swath profile analysis shows that the top of the Siming Mountain exhibits remnants of planation surface. When the planation surface was formed, the northeast tectonic activity was resurrected, which caused the basalt to cover it. The results show that the elevation of planation surface is close to the basalt elevation, whereby the southern parts of the mountain are higher by about 300 m than the north. The Hypsometric Integral analysis of each sub-basin reveals HI values are 0-0.35, 0.35-0.45 and 0.45-0.60, accounting for 47.31%, 30.58% and 22.11%. In this paper, the geomorphological features of the study area are simply divided by the HI value. It is found that the HI values in the study area are less than 0.6, and the landforms in the mature stage are subdivided according to elevation distribution in the EP chart, which are the older stage and the typical mature stage. The rest is corresponding to the old age of the landform, which indicates that the study area is now dominated by external force denudation.
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    Spatio-temporal analysis about the primary productivity of Mentougou District in Beijing from 2003 to 2014
    WANG Jiu-zhong, WU Ming-quan
    Journal of East China Normal University(Natural Sc    2018, 2018 (1): 163-170.   DOI: 10.3969/j.issn.1000-5641.2018.01.016
    Abstract411)   HTML10)    PDF (797KB)(737)      
    Ten years NPP products of Mentougou District from 2003 to 2014 are generated using CASA model and Landsat remote sensing data. It is used to show the spatial distribution characteristic about Mentougou District' NPP. Inter-annual variability characteristic about Mentougou District' annual amount NPP is analyzed using MODIS17A3 products from 2003 to 2014. The intra-annual variability characteristic about Mentougou District' GPP was analyzed based on MODIS17A2 product in some typical years (namely 2004, 2007, 2008, 2009, 2011, 2012). The results show that the NPP of Mentougou District has a significant spatial differentiation characteristic that the value of NPP is low on median and it is high on other region. The NPP value is very low distributed along the river valleys. The annual amount NPP has no significant increasing or decreasing trend from 2005. GPP fluctuated significantly during the year. The differences in GPP/NPP between May and September contributed the most to the differences in GPP/NPP among different years.
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    Existence and non-existence of global solutions for the wave equations
    JIN Shou-bo, ZHANG Zu-feng
    Journal of East China Normal University(Natural Sc    2018, 2018 (2): 1-10.   DOI: 10.3969/j.issn.1000-5641.2018.02.001
    Abstract460)   HTML20)    PDF (299KB)(799)      
    In this paper we investigated the initial boundary value problem for a class of higher order wave equations with two opposite source terms. Firstly, we introduced the latest research progress of the wave equations and defined some important generalized functionals and sets, then the properties of the functionals were discussed. Secondly, it was proved that these sets were invariant under the wave equation. Finally, we proved the existence of global weak solutions by the combination of Galerkin approximation method and potential well method, and obtained the conditions of the non-existence of global weak solutions by using the potential well method and the convexity. The optimal threshold results were given for the existence and non-existence of global weak solutions.
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    Global attractors for the coupled damped suspension bridge equations with linear memory
    HUANG Shang-shang, MA Qiao-zhen
    Journal of East China Normal University(Natural Sc    2018, 2018 (2): 11-22.   DOI: 10.3969/j.issn.1000-5641.2018.02.002
    Abstract489)   HTML135)    PDF (315KB)(612)      
    In this paper, we investigate the long-time dynamical behavior of coupled suspension bridge equations with linear memory. We obtain the existence of the global attractors in the weak Hilbert space by using methods of energy estimates and contractive function.
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    Exploring equivalent definitions of eulerian graphs
    SUN Hui, YAO Bing
    Journal of East China Normal University(Natural Sc    2018, 2018 (2): 23-30,40.   DOI: 10.3969/j.issn.1000-5641.2018.02.003
    Abstract402)   HTML10)    PDF (739KB)(663)      
    From the topic of equivalent propositions of eulerian graph to start our study, we try to dig the topology of eulerian graph, and to describe eulerian graph from the view of different insights. Finally, we obtain four new equivalent propositions of eulerian graph by the technique of "concentration" and "dilution" operations, which can be transformed into two feasible algorithms.
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    Approximation properties of the left quasi-interpolants Gamma operators in Orlicz spaces
    HAN Ling-xiong
    Journal of East China Normal University(Natural Sc    2018, 2018 (2): 31-40.   DOI: 10.3969/j.issn.1000-5641.2018.02.004
    Abstract367)   HTML10)    PDF (291KB)(535)      
    In order to reach better approximation degree, people start to study the quasiinterpolants of operators. In this paper, approximation properties of left quasi-interpolants Gamma operators are discussed by the tools of Ditizan-Totik modulus, K-functional, Hölder's inequality, Cauchy-Schwarz's inequality and Laguerre polynomials and so on. Then we obtain the direct, inverse and equivalence theorems which generalize the results of left quasi-interpolants Gamma operators in Lp space and improve the approximation properties of Gamma operators in Orlicz spaces.
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    Efficient verifiable privacy-preserving recommendation system
    SONG Chun-zhi, DONG Xiao-lei, CAO Zhen-fu
    Journal of East China Normal University(Natural Sc    2018, 2018 (2): 41-51,62.   DOI: 10.3969/j.issn.1000-5641.2018.02.005
    Abstract457)   HTML16)    PDF (633KB)(661)      
    To address the problem of privacy disclosure in traditional personalized recommendation systems, this paper proposes an efficient verifiable privacy-preserving recommendation system, which can provide user the way to verify the correctness of the resulting model of cloud computing under the premise of protecting user's data privacy. This paper uses ridge regression to find the best-fit linear curve of user's input data, and implements Yao's garbled circuit to realize the computation and the correctness verification of the recommendation model. The user and the cloud use a newly-devised privacy preserving data aggregation method named AGG (Aggregation) to replace public key homomorphic encryption used in most existing work, which can reduce the computational overhead of the user and the cloud, thus making the system more efficient. The security analysis and the efficiency analysis of the scheme are given at the end of the article.
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    Balancing travel satisfaction algorithm for multi-day trip planning
    XU Kan, ZHENG Jun
    Journal of East China Normal University(Natural Sc    2018, 2018 (2): 52-62.   DOI: 10.3969/j.issn.1000-5641.2018.02.006
    Abstract410)   HTML10)    PDF (588KB)(629)      
    Location-based service is a kind of service that obtains the location of mobile user and provides it according to location. Among them, one of the active topics is trip planning. People can make different trip planning to meet their multiple requirements by location-based service. However, in most studies, trip planning only focus on searching one route in many locations according to user's demands. When people are trying to visit the city more than one day, the travel satisfaction of the routes provided by previous researches would reduce by day. Hence, the previous work cannot meet the requirement of multi-day trip planning. To improve the satisfaction stability of multi-day trip planning, we use trip day as one of the multi-day travel planning parameters. We acquire points of interest (POIs) information (e.g., location, scoring, category, etc.) and construct a POI network model, obtain optimal trip routes through heuristic algorithm, develop an effective multi-day travel planning. The experimental results demonstrate that our proposed method can plan a multi-day trip with high quality and more balanced route.
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    Detection of fake plate vehicles based on traffic data stream
    LI Min-xi, MAO Jia-li, YUAN Pei-sen, JIN Che-qing
    Journal of East China Normal University(Natural Sc    2018, 2018 (2): 63-76,100.   DOI: 10.3969/j.issn.1000-5641.2018.02.007
    Abstract571)   HTML73)    PDF (1763KB)(765)      
    Since vehicles using fake plate violate traffic laws and regulations, infringe the rights of legal license owners and harm social benefits, it is therefore of great urgency to solve this social problem. In current detection methods, unified speed threshold is used to detect fake plate vehicles. Once an inappropriate threshold was set, it would lead to misjudgements and omissions, and thereby results in a low judgement accuracy. To solve this problem, we propose a two-phase fake plate vehicles detection framework. In the offline part, we train a distributed speed model based on sparse traffic trajectory data to calculate time-dependent thresholds for different roads. In the online part, we apply a sliding-window method to monitor whether a car is an outlier. If a car is continually detected as an outlier, it will be judged as a fake, and vice versa. We then use a real dataset to evaluate our method. The results demonstrate negative influences of noise data can be avoided by our method, so the accuracy of fake plate vehicles detection can be improved significantly.
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    Woodpecker: Fine-grained contention simulation database testing framework
    LI Jie-ying, LI Yu-ming, ZHANG Xiao-lei, ZHANG Rong
    Journal of East China Normal University(Natural Sc    2018, 2018 (2): 77-88.   DOI: 10.3969/j.issn.1000-5641.2018.02.008
    Abstract432)   HTML9)    PDF (695KB)(588)      
    With the rich and the growing peformance requirement of applications, various database developments appear, such as row-based, column-based, main memory database and so on. Hence database testing becomes more and more important. Existing automated testing frameworks of database have some problems in flexibility of test, integrality of function and the granularity of test. Firstly they can't support functional test, performance test and DBMS functional test at the same time. Secondly popular benchmark TPC-C simulates workload contention by warehouse which can't quantify contention and maybe execution is different with expectation. Finally the use of test case is static, they can't organize and run test case dynamically. As a consequence this paper presents a flexible database testing framework which is called Woodpecker, its test task descriptive language has abundant primitives, easy-to-use and could write test case efficiently. Woodpecker is the first test framework that can mix three above-mentioned tests in one test case, and simulates workload contention in fine granularity which include read-write contention and write-write contention. We use a simple case in auto increment testing to show the descriptive language's advantage, last we verify the capacity of mixing three tests in Woodpecker, and besides, we show the results of workload contention simulation in performance test.
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    Design and implementation of PK answer based on WebSocket
    ZHU Xiang, DONG Qi-wen, YU Ke-ren
    Journal of East China Normal University(Natural Sc    2018, 2018 (2): 89-100.   DOI: 10.3969/j.issn.1000-5641.2018.02.009
    Abstract453)   HTML29)    PDF (892KB)(997)      
    The development of the Internet has brought great convenience to people's life and work, at the same time, people have more demand for Internet applications. How to help students answer questions onlineis increasingly becoming a reality demand for primary and secondary schools as well as online education platforms. From this realistic demand, an online PK (Player Killing) answer function is proposed. Through the online PK answer, students' interest in learning and their ability to grasp knowledgecan be enhanced.
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    Electrical manipulation of Rashba spin-orbit coupling in the two-dimensional transition metal dichalcogenide
    YAO Qun-fang, CAI Jia, GONG Shi-jing
    Journal of East China Normal University(Natural Sc    2018, 2018 (2): 101-108.   DOI: 10.3969/j.issn.1000-5641.2018.02.010
    Abstract456)   HTML15)    PDF (1090KB)(1377)      
    Using the first-principles density functional theory calculations, we investigate the Rashba spin-orbit coupling of the transition metal dichalcogenide (TMD) monolayers MX2(M=Mo, W; X=S, Se, Te) induced by the external electric field. It is found that the anions X play an important role on the Rashba spin-orbit coupling effect. With the increase of the atomic number of X, Rashba spin-orbit splitting around the Γ point increases more distinctively, and the external electric field can hardly influence the cations because of the coverage by the anions. Thus the strength of the Rashba spin-orbit coupling follows the sequence:WTe2 > MoTe2 > WSe2 > MoSe2 > WS2 > MoS2. Furthermore, the distribution of the spin polarization along the high symmetry line Γ-K/K' turns from the vertical direction to the two-dimensional plane under the external electric fields, and the in-plane spin polarization distribution rises with the increase of the external electric field.
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    Coherent acoustic phonon inmagnetic thin films excited by femtosecond laser
    YAN Jia-qi, LI Wei, LOU Shi-tao, ZHANG Xiao-lei
    Journal of East China Normal University(Natural Sc    2018, 2018 (2): 109-114.   DOI: 10.3969/j.issn.1000-5641.2018.02.011
    Abstract620)   HTML11)    PDF (576KB)(565)      
    The interaction between the femtosecond laser pulse and the MnIr layer in the magnetic thin film excites the coherent acoustic phonon with an initial phase of 90° and a propagation velocity of 4 300 m/s. The vibration frequency of the acoustic phonon is independent of the laser energy density and is inversely proportional to the total thickness of the magnetic thin film. And the acoustic phono can propagate in the adjacent metal layers due to the high lattice matching. The electron temperature in the magnetic thin film increases sharply absorbing by femtosecond laser pulse, then an decreasing electron temperature gradient with increasing depth is generated instantaneously by the absorption of the laser which lead to the lattice oscillate coherently in the depth direction, that is, the acoustic phonon. In addition, the frequency of the acoustic phonon changes caused by the applied magnetic field is within the experimental error range, indicating that the magnetic interaction is very weak compared to the electrical interaction in the lattice.
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    Luminescence characteristics of Eu2+-activated white-emitting phosphor prepared from solar cell cutting Si powder
    YU Xin-yang, CAI Ya-guo, SUN Zhuo, PIAO Xian-qing
    Journal of East China Normal University(Natural Sc    2018, 2018 (2): 115-124.   DOI: 10.3969/j.issn.1000-5641.2018.02.012
    Abstract431)   HTML9)    PDF (1454KB)(657)      
    Eu2+-activated white-emitting phosphors were synthesized by the process of ammonia nitridation at high temperature with the raw material of silicon powder from crystalline silicon solar cells cutting sludge. The effect of Eu2+ doping concentrations on structural and luminescent properties of phosphors was studied in detail. It turns out that the principal crystalline phase of the sample is the mixture of Ca2SiO4, CaSiO3 and Ca2Si5N8. These phosphors can be effectively excited in the range of 300~450 nm, showing intense absorption in ultraviolet to near-ultraviolet region. In addition, they exhibit intense white emissions with CIE (Commission Internationale de L'Eclairage) coordinates of (0.327 5, 0.386 6) under 370 nm excitation with color temperature of 5 705 K(5 431.85℃). There are two luminescence centers in the host, which locate at 470 nm and 570 nm, respectively. With the increase of the doping concentration of Eu2+, the emission reaches an intensity saturation and the optimum doping content of Eu2+ is 10.0 mol% due to the interaction among the activator ions which result in an concentration quenching. Using such a single phosphor, a white light output can be directly achieved combined with UV chip.
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    Research progress of the target proteins by proteasome activator REGγ in human cancers
    CHEN Shao-jun, LI Xiao-tao, ZHENG Jun-hua
    Journal of East China Normal University(Natural Sc    2018, 2018 (2): 125-130,159.   DOI: 10.3969/j.issn.1000-5641.2018.02.013
    Abstract630)   HTML13)    PDF (615KB)(547)      
    The proteasome activator REGγ, which is a member of REG (11 S) proteasome activator family, can stimulate the proteolytic activity of the 20 S core proteasome to degrade proteins independent of ubiquitination and ATP. In recent years, more and more studies show that REGγ is dysregulated in various human cancers and closely related to the oncogenesis and development of cancers. The potential mechanism by which REGγ exerts its role in cancer development is degradation of various target proteins. We now review the target proteins of REGγ in human cancers in order to further understand the mechanism by which REGγ exerts its role in cancer development, and to uncover the potential of REGγ to serve as a new marker for diagnosis and a novel target for treatment in human cancers.
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    Studies of seasonal variation on genetic toxicity of typical fine particulate matter samples in Shanghai
    ZHANG Ying, YANG Jing, CHEN Xiao-qian, YANG He-xing, YIN Hao-wen
    Journal of East China Normal University(Natural Sc    2018, 2018 (2): 131-140.   DOI: 10.3969/j.issn.1000-5641.2018.02.014
    Abstract399)   HTML13)    PDF (835KB)(609)      
    To explore the genetic toxicity on different components of PM2.5 in Huinan and Pudong during winter and summer, the SOS chromotest is used to detect the genetic toxicity of the total particulate, the organic extract and the water-soluble component. Results shows that tests of the genetic toxicity on the total particulate in Huinan are positive at the highest concentration of 2 mg·mL-1 both in winter and summer, also are positive in Pudong respectively at the concentration of 1 mg·mL-1 in winter and at the highest concentration of 2 mg·mL-1 in summer. Tests of the genetic toxicity at two stations both in winter and summer on the water-soluble component are positive at the highest concentration of 2 mg·mL-1and negative on the the organic extract in the range of 0.000 2 mg·mL-1and 2 mg·mL-1. To further compare the genetic toxicity of the PM2.5 in Huinan and Pudong during winter and summer when exposed to the same volume air, the genetic toxicity of the different components are expressed as the content of the 4-nitroquinoline oxide (4-NQO) per cubic meter of air. Results indicat that the genetic toxicity of the fine particulate matter in Shanghai Puding and Huinan is seasonal and higher in summer than in winter. Furthermore the genotoxic component and the concentration of the total particulate and the water-soluble during winter and summer may be different. It, combined with the result of existing studies that pollutants concentration or components of fine particulate matter were generally higher in winter than in summer at multiple sites in Shanghai, is speculated that the genetic toxicity of atmospheric particulates in every part of Shanghai has similar seasonal change rule. The genotoxic effect of the organic extract is not significant. The main source of the genetic toxicity in the fine particulate matter may be the water-soluble component. The atmospheric pollution at Pudong stationwas continuously serious and equivalent to Huinan stationon the pollution level and the genetic toxicity in same seasons. It is speculated that the genotoxic chemical compositions of atmospheric particulate matter at Pudong station and Huinan station are similar.
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    Pollution effects of atmospheric deposition on heavy metals in leafy vegetables and its health risks
    ZHOU Xiao-xiao, BI Chun-juan, WANG Meng, ZHOU Ya, CHEN Zhen-lou
    Journal of East China Normal University(Natural Sc    2018, 2018 (2): 141-150.   DOI: 10.3969/j.issn.1000-5641.2018.02.015
    Abstract443)   HTML11)    PDF (666KB)(539)      
    In order to study the pollution effects of heavy metals in atmospheric deposition on leafy vegetables and health risks via consuming vegetables, this research chooses a farmland near the suburban Shanghai as a study area, makes comparative analysis of heavy metal contents in vegetables samples, including Shanghai Green cabbage, leaf lettuce, amaranth and water spinach, both in outdoor and greenhouses, and makes the health risk assessment of the edible parts of vegetables using the target hazard quotient (THQ). The results show that the heavy metal contents of the vegetables in outdoor are higher than those in greenhouses. The average contents of Zn, Cr, Cu, Pb, Cd, Hg, and As in outdoor vegetables are 7.32, 0.91, 0.52, 0.007, 0.029, 0.002, and 0.014 mg·kg-1, respectively; among which, the contents of Zn, Cr, Cu, Cd, and Hg are 26.4%, 28.4%, 83.3%, 33.9%, and 14% higher than those in greenhouses, respectively. The enrichment factors of greenhouse vegetables are higher than those of outdoor vegetables, showing that the heavy metals of outdoor vegetables are greatly influenced by atmospheric deposition. Different vegetables have different enrichment capacity of heavy metals. Amaranth has the strongest enrichment capacity for Zn, Hg, As and Cu; while water spinach has the most powerful enrichment capacity for Pb. TotalTarget Hazard Quotient (TTHQ)values ofvegetables in outdoor are between 1.41 to 2.99 with an average of 2.29; while those in greenhouses are between 1.10 to 2.19 with an average of 1.85, which is 23.4% lower than the outdoor values. There is a threat for the health of adult and children. The risk of consuming vegetables in outdoor is higher than that in greenhouses. Atmospheric deposition is one of the important sources of heavy metals in vegetables. Hence, we suggest to avoid outdoor cultivating vegetables in high risk areas with atmospheric pollution of heavy metals, thus reducing the impact of atmospheric deposition on enrichment of heavy metals in vegetables.
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    Geochemical characteristics of the peat profile in the Yangbajing basin, Tibetan, China and its paleoenvironmental implications
    MENG Qing-hao, NIU Rui, ZHENG Xiang-min, Zhou Li-min, SUN Cheng-cheng, WANG Lin
    Journal of East China Normal University(Natural Sc    2018, 2018 (2): 151-159.   DOI: 10.3969/j.issn.1000-5641.2018.02.016
    Abstract424)   HTML9)    PDF (1371KB)(639)      
    The peat contains abundant information about climate change.In this study, the ratios of characteristic elements in the Yangbajing basin, Tibetan Plateau, are found to be an good indicator for evaluating the regional sedimentary environment (e.g., the change of wet and dry stages), according to the analytical results of special element rations (Fe/Mn, Ba/Sr, K2O/Na2O), humification and mercury (Hg) records in the peat cores. The paleoclimate evolution in the Yangbajing basin is classified as three stages as revealed by the elemental geochemical records:Temperature fluctuates and shows an overall increasing trend between 9.1~7.6 cal ka BP. The sedimentary environment is relatively wet during this period. Significant and frequent fluctuation of temperature is observed between 7.6~4.5 cal ka BP. The sedimentary environment tends to be dry; the temperature fluctuats less and shows a decreasing upward trend 4.5~3.5 cal ka BP. The sedimentary environment tends to be warm and wet. A total of four drying events are recorded in the peat profile, which occurs at approximately 5.8, 6.1, 8.2 and 8.8~8.5 cal ka BP, respectively. The four events recorded in the peat core in the Yangbajing basin are consistent with the regional and global climate records.
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    Analyses of saltwater intrusion at the water intake of Qingcaosha reservoir in the Changjiang Estuary in dry season from 2015 to 2017
    LI Guo-ping, ZHU Jian-rong
    Journal of East China Normal University(Natural Sc    2018, 2018 (2): 160-169.   DOI: 10.3969/j.issn.1000-5641.2018.02.017
    Abstract420)   HTML13)    PDF (4723KB)(616)      
    Based on the measured salinity at the upper and lower water gate of Qingcaosha reservoir from January to Match from 2015 to 2017, and combined the measured river discharge at Datong station, wind at weather station at Chongming eastern shoal, water level at Baozhen hydrologic station and salinity at Chongxi hydrologic station, the frequency and source of saltwater intrusion at the water intake of Qingcaosha reservoir in the last three years were analyzed. The frequencies at the water intake of the reservoir from January to March in 2015, 2016 and 2017 were three, one and one of saltwater intrusion, respectively. Only one time of saltwater intrusion in the dry season of 2016 and 2017 occurred due to the higher river discharge. Among the total five times of saltwater intrusion happened at the water intake from January to March in the last three years, only one of saltwater source was from upstream, i.e., the saltwater-spilling-over from the North Branch into the South Branch, which took about 3 days for the saltwater moving from the Chongxi hydrologic station to the water intake of the reservoir; Four times of saltwater source were from downstream, i.e., the saltwater intrusion through the North Channel, which appeared in neap tide or medium tide after neap tide, was weaker under general wind speed, and was stronger under strong north wind. In view of the saltwater intrusion at the water intake of Qingcaosha reservoir in the last three years, the frequencies of saltwater intrusion coming from the downstream of the North Channel were increased distinctly, and the saltwater intrusion would be severe if strong north wind occurs in neap tide.
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    Study of the ebb sediment diversion ratios during wet season in the South and North Passage, Changjiang Estuary
    YANG Wan-lun, DAO Fu-hai, LUAN Hua-long, GE Jian-zhong, DING Ping-xing
    Journal of East China Normal University(Natural Sc    2018, 2018 (2): 170-180.   DOI: 10.3969/j.issn.1000-5641.2018.02.018
    Abstract501)   HTML17)    PDF (1399KB)(643)      
    This study investigates the characteristics of the ebb water and sediment diversion ratios during wet season in the North Passage, Changjiang Estuary and the reasons for the differences within neap-spring tidal cycles based on field measurements. The results of the measurements indicate that the averaged ebb flow diversion ratios of the North Passage in spring and neap tide are 41.9% and 43.1%, respectively, while the averaged ebb sediment diversion ratios of the North Passage in spring and neap tide are 35.1% and 39%,the averaged ebb sediment diversion ratios of the North Passage in spring can approximate representatively ebb sediment diversion status. The ebb sediment diversion ratio of the North Passage is dependent on the ratios of mean flow velocity, suspended sediment concentration and section areas of the North and South Passage. And these parameters show minor changes within neap-spring tidal cycles. Therefore, it can be concluded that the differences of ebb flow and sediment diversions of the North Passage within neap-spring tidal cycles are limited.
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    A note on Kronecker's double sum and non-holomorphic Eisenstein series
    SHEN Li-chien
    Journal of East China Normal University(Natural Sc    2018, 2018 (3): 1-17.   DOI: 10.3969/j.issn.1000-5641.2018.03.001
    Abstract379)   HTML20)    PDF (255KB)(608)      
    A family of non-holomorphic Eisenstein series of weight k and level N is generated from twisting of the Kronecker double series by Dirichlet characters and from which we will derive its representation in terms of the Whittaker function and the functional equation for the Eisenstein series.
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    Hom-spaces for subregular nilpotent representations of sl(n+1)
    LI Yi-yang, SHU Bin, YE Gang
    Journal of East China Normal University(Natural Sc    2018, 2018 (3): 18-24,45.   DOI: 10.3969/j.issn.1000-5641.2018.03.002
    Abstract373)   HTML25)    PDF (323KB)(582)      
    Let g=sl(n+1) be the special linear Lie algebra over an algebraically closed field k of prime characteristic p with pn+1. We show that the hom-spaces between any two baby Verma modules in the same given block are always nonzero for subregular nilpotent representations of g, which reveals a complete linkage atlas for baby Verma modules.
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    Irreducible sl2-decomposition for a highest weight sl2-module
    CHAI Wei-jun, XIA Li-meng
    Journal of East China Normal University(Natural Sc    2018, 2018 (3): 25-29.   DOI: 10.3969/j.issn.1000-5641.2018.03.003
    Abstract383)   HTML15)    PDF (159KB)(518)      
    In this paper, we study the irreducible highest weight module L0) of affine Lie algebra . Since the three-dimensional simple algebra sl2 is regarded as a Lie subalgebra of , L0) naturally becomes a sl2-module. We present the irreducible decomposition of L0) as a sl2-module.
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    The explicit structure of projectively flat Finsler metrics with three parameters
    LIU Jin-meng, SONG Wei-dong
    Journal of East China Normal University(Natural Sc    2018, 2018 (3): 30-37.   DOI: 10.3969/j.issn.1000-5641.2018.03.004
    Abstract343)   HTML13)    PDF (248KB)(504)      
    In this paper, projectively flat Finsler metrics are considered. A class of projectively flat Finsler metrics with three parameters are formed. Moreover, the sufficient and necessary conditions for the measurement to be considered projectively flat was obtained. In particular, the flag curvature expression of projectively flat Finsler metrics are presented.
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    L2 harmonic 2-forms on a hypersurface in Euclidean space
    ZHANG Quan-rui, LIU Jian-cheng
    Journal of East China Normal University(Natural Sc    2018, 2018 (3): 38-45.   DOI: 10.3969/j.issn.1000-5641.2018.03.005
    Abstract364)   HTML15)    PDF (275KB)(532)      
    In this paper, we study L2 harmonic 2-forms on a complete hypersurface M of Euclidean space Rn+1(n ≥ 3). By applying the Bochner technique, we prove that if the Ln(M) norms of the traceless second fundamental form Φ and the mean curvature vector H are both bounded from above by certain constants which depend only on n, then the L2 harmonic 2-forms on M are parallel. Furthermore, if M is a non-minimal hypersurface, then there is no nontrivial L2 harmonic 2-form on M.
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    AM(s)-Convex function and its Jensen-type inequality
    SONG Zhen-yun, HU Fu-gao
    Journal of East China Normal University(Natural Sc    2018, 2018 (3): 46-54,120.   DOI: 10.3969/j.issn.1000-5641.2018.03.006
    Abstract450)   HTML14)    PDF (547KB)(490)      
    Based on the convexity and general convexity of a function, the authors study extending issues of a convex function. Firstly, the concept and sign of weighted r-th power s-mean of n positives are introduced; secondly, the AM(s)-convex function is defined by weighted r-th power s-mean; thirdly, the judgment theorem and operation properties of AM(s)-convex function are discussed; and finally, the Jensen-type inequality of the AM(s)-convex function is proved and an equivalent form is provided. The study shows that the AM(s)-convex function is a subset of general convex functions that includes many convex functions. Studying the AM(s)-convex function with the method of weighted r-th power s-mean is an effective way of extending and studying convex functions. This method explores a new approach to extending and studying convex functions.
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    Chinese named entity relation extraction for enterprise knowledge graph construction
    SUN Chen, FU Ying-nan, CHENG Wen-liang, QIAN Wei-ning
    Journal of East China Normal University(Natural Sc    2018, 2018 (3): 55-66.   DOI: 10.3969/j.issn.1000-5641.2018.03.007
    Abstract656)   HTML35)    PDF (902KB)(979)      
    The enterprise knowledge graph is a kind of domain knowledge base for the financial field to describe business relationships between enterprises. Although the domain knowledge graph is not broadly covered in the field, the precision of the knowledge is better than with an open knowledge graph. Despite the fact that open knowledge graphs have made significant advancements in recent years, vertical fields-especially business-have not seen in-depth applications in practice; this has resulted in significant demands on the enterprise knowledge graph. This paper proposes a Chinese entity relation extraction method based on classification for the limitation of extraction results. In this method, the maximum entropy model is used to analyze the data of selected companies' announcements to determine the optimal feature template. The results show that accuracy rates reach over 85% in the enterprise bulletin data set.
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    Algorithm for service optimization under multi-QoS constraints for data services in a food traceability system
    YUAN Pei-sen, LI Wei, REN Shou-gang, XU Huan-liang
    Journal of East China Normal University(Natural Sc    2018, 2018 (3): 67-76.   DOI: 10.3969/j.issn.1000-5641.2018.03.008
    Abstract354)   HTML13)    PDF (656KB)(545)      
    The concept of data services plays an important role in the era of big data. In this paper, an optimization algorithm for web services in food safety traceability is investigated based on the SOA (Service-Oriented Architecture) framework. Traceability services are commonly data-intensive systems, which need to combine multi-source web services. In this paper, by extracting important QoS (Quality of Service) indexes from the web and data services of the system, a multi-QoS based benefit ratio (MQBR) is established, which is then used on the traceability platform for food security management. Based on the MQBR model, the skyline and heuristic method of artificial intelligence is proposed for optimizing the efficiency and quality of service selection. Experiments are conducted to prove the validity of the algorithm. The methods of our study are designed and applied to a food security management application, with multiple QoS constraints in the traceability systems, to improve the overall performance and service quality.
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    Algorithm for video click-through rate prediction
    KUANG Jun, TANG Wei-hong, CHEN Lei-hui, CHEN Hui, ZENG Wei, DONG Qi-min, GAO Ming
    Journal of East China Normal University(Natural Sc    2018, 2018 (3): 77-87.   DOI: 10.3969/j.issn.1000-5641.2018.03.009
    Abstract519)   HTML25)    PDF (740KB)(649)      
    Click-through rate prediction has played an important role in video recommendation systems. A video recommendation system can suggest media to users based on the results of click-through rate prediction. In this way, users may be more likely to click the videos recommended by platforms. However, given the volume and imbalance of data in some applications, the accuracy of click-through rate prediction may be very low. To improve the performance, this paper proposes an integrated approach by combining feature engineering with techniques from machine learning. In the first stage, the algorithm uses feature engineering to extract user, video, and combinational features from the original dataset. In the second stage, the algorithm predicts the click-through rate by employing supervised models of logistic regression, factorization machine, and gradient boosting decision tree combined with logistic regression. The experimental results illustrate that the prediction accuracy of the factorization machine model and the gradient boosting decision tree combined with logistic regression model are better than the logistic regression model. Moreover, the cross combination of user and video features can improve the accuracy of the click-through rate prediction.
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    The design and implementation of an efficient order management system based on Cedar
    PAN Yu-chen, LI Yu-ming, ZHANG Chun-xi, ZHANG Rong, HONG Dao-cheng
    Journal of East China Normal University(Natural Sc    2018, 2018 (3): 88-96.   DOI: 10.3969/j.issn.1000-5641.2018.03.010
    Abstract455)   HTML23)    PDF (1642KB)(664)      
    With the development of Internet, enterprises are increasingly relying on the Internet for core functionality of their business systems. Legacy business systems which were based on centralized data management platforms, such as MySQL, have shortcomings in usability when the systems are used on the Internet instead of for internal business processes. They are not suitable for supporting new business requirements which require scalability with concurrent transactions and conflict resolution. In this paper,we design and implement a scalable order management system which supports order storage, assigning orders, and order rushes using the distributed Cedar database and Netty communication framework. The characteristics are designed on the basis of an in-depth analysis of current business characteristics. We verify our design on real workload of a Haier system. The experimental results show that the proposed order management system has good scalability, high throughput, and low latency.
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    Attribute reduction based on information entropy of approximation boundary accuracy
    LIANG Bao-hua, WU Qi-lin
    Journal of East China Normal University(Natural Sc    2018, 2018 (3): 97-108,156.   DOI: 10.3969/j.issn.1000-5641.2018.03.011
    Abstract424)   HTML13)    PDF (764KB)(549)      
    From an information point of view, only the size of knowledge granularity is taken into account, while the importance of attributes cannot be objectively and comprehensively measured. First, starting from the perspective of algebra, the concept of approximate boundary accuracy is proposed. Afterwards, according to the definition of relative fuzzy entropy, this paper proposes two new concepts for relative information entropy and enhanced information entropy. Compared with relative fuzzy entropy, the proposed information entropy has an obvious magnification effect. Two new methods of attribute reduction are subsequently proposed by incorporating approximate boundary accuracy into relative information entropy and enhanced information entropy. Computing U/(Bb) while making full use of U/B can greatly reduce the computational overhead on time. Finally, through the experimental analysis and comparison, it is validated that the proposed algorithm has feasibility and effectiveness in both reduction quality and classification accuracy.
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    Design and implementation of an authorization system for a graduate school information
    GU Hang, XIA Fan, SONG Shu-bin, XIAO Li-min, DONG Qi-wen, XU Lin-hao, ZHOU Ao-ying
    Journal of East China Normal University(Natural Sc    2018, 2018 (3): 109-120.   DOI: 10.3969/j.issn.1000-5641.2018.03.012
    Abstract461)   HTML19)    PDF (1088KB)(656)      
    Authentication and authorization are critical to ensuring the security of data and services in software systems. To satisfy the need for authorization management during the development of the next generation information platform for East China Normal University's Graduate School, this paper proposes an access domain-based authorization module and uses Spring Security components to implement a hierarchical, configurable, high-performance privilege interceptor. The approach can effectively defend against popular network attacks, such as session attacks and CSRF, guarantee low latency for web service access, and provide a flexible way to meet the frequently changing authorization requirements of faculty from different schools and departments.
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    An analysis of the hadron structure in covariant chiral effective theory
    WEN Li-hong, YANG Ji-feng
    Journal of East China Normal University(Natural Sc    2018, 2018 (3): 121-128.   DOI: 10.3969/j.issn.1000-5641.2018.03.013
    Abstract437)   HTML12)    PDF (328KB)(536)      
    The matrix elements of twist-2 operators related to nucleon-parton distributions were calculated at one-loop level in the framework of covariant chiral perturbation theory. It was found that all who violate chiral power counting reside in the local terms depending on nucleon mass; hence, they could be readily removed through local counterterms, namely the contributions left over fulfill chiral power counting just like with HBChPT (Heavy Baryon Chiral Perturbation Theory). Meanwhile, one may arrive at incorrect behaviors near baryon thresholds due to the oversimplification of baryon propagators in HBChPT. The results here further support the proposition that the approach of covariant chiral perturbation theory with proper subtractions could both preserve the correct threshold behaviors and fulfill chiral power counting, and hence is a framework more suitable for investigating hadron physics.
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    Influence of dipolar magnetic interaction on the LDGMI effect of Fe-based nanocrystalline ribbons
    SU Ya-pan, PAN Hai-lin, ZHAO Zhen-jie, YUAN Meng-ping
    Journal of East China Normal University(Natural Sc    2018, 2018 (3): 129-135,156.   DOI: 10.3969/j.issn.1000-5641.2018.03.014
    Abstract486)   HTML12)    PDF (995KB)(461)      
    In this paper, the hysteresis loops, LDGMI (longitudinal driven giant magnetoimpedance) effect, and impedance phase variations of Fe73.5Cu1Nb3Si13.5B9 nanocrystalline ribbons are investigated. The results show that the anisotropy field and the platform width of the LDGMI curves increase linearly with the number of nanocrystalline ribbons. This stems from the dipole-dipole interactions between the ribbons. Simultaneously, the "platform" width was modulated by the frequency and intensity of the driven field, the broad field amplified with the frequency of the driven field increasing, and gradually decreased with the intensity of driven field increasing. Hence, the work has important reference value for the development of LDGMI devices with multiple cores.
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    Detecting spatiotemporal hotspots for vehicle thefts by multi-scale analysis
    REN Zhe-hao, ZHANG Hao-tian, LIU Wei-hang, GUO Zhong-yang
    Journal of East China Normal University(Natural Sc    2018, 2018 (3): 136-145.   DOI: 10.3969/j.issn.1000-5641.2018.03.015
    Abstract431)   HTML12)    PDF (1603KB)(495)      
    The detection of crime hot spots has become increasingly prominent in the conversion from reactive to active policing. There exist many crime analysis methods with good results. This paper focuses on scale effects in analysis. We proposed two multi-scale methods to detect temporal and spatial hotspots for vehicle thefts in a district, whose results were used for policing references. These two methods and their results are stated as follows:① a scaling method is proposed and combined with a rigid process to aggregate temporal data. Through this combination, temporal hotspots can be detected when data are not sufficient under mono-scale. Results showed that daily hot spots (30 days) and hourly hot spots (20 hours) of vehicle thefts are significant at the study site, on which the rearrangement of shift intervals can be based;② on the basis of daily hot spots, we set a median case density of a convex hull as the evaluation function when applying DBSCAN. The optimal scale, verified by the popular Prediction Accuracy Index, was adaptively chosen. We found that several metro line stations and residence zones need key protection.
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    Validation of temperature and relative humidity profiles with satellite hyperspectral infrared sounder over East China
    GU Ya-ru, LIU Yan-An, LIU Chao-shun, LI Zheng-long
    Journal of East China Normal University(Natural Sc    2018, 2018 (3): 146-156.   DOI: 10.3969/j.issn.1000-5641.2018.03.016
    Abstract434)   HTML14)    PDF (2041KB)(539)      
    Satellite hyperspectral infrared data provide high temporal and spatial resolution information on atmospheric temperature and humidity profiles. They are important data source for numerical weather prediction models. Quality control of the data and correct characterization of observation errors are key to the successful application of assimilation. The radiosonde data is a direct measurement with high precision, which can be used to validate satellite retrievals. During the flood season of East China, high density radiosonde observations provide a valuable opportunity to examine the quality and quantify the error of Atmospheric Infrared Sounder (AIRS) retrieved products, both of which have a similar observation time at 14:00 Beijing time. This study focuses on East China during the summer of 2015. Results show that the AIRS retrieved temperature profiles are in good agreement with the radiosonde data, whilst the AIRS retrieved relative humidity profiles show the phenomenon of wetter in higher layers and drier in lower layers. The RMSE difference of temperature and relative humidity range from 1.02℃ to 2.49℃ and from 12.91% to 23.43%, respectively. Under the AIRS and AMSU (Advanced Microwave Sounding Unit) joint inversion products, the accuracy of retrieved temperature and humidity profiles are gradually degraded with the increasing number of total cloud fraction, but the results maintain a certain accuracy as a whole. This study provides a basis for the satellite data assimilation application under cloud cover.
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    Study on spatial distribution of residential care facilities in Shanghai
    CHEN Jie, YAO Shen-jun, WU Jian-ping, HUANG Le-le, REN Zhe-hao
    Journal of East China Normal University(Natural Sc    2018, 2018 (3): 157-169.   DOI: 10.3969/j.issn.1000-5641.2018.03.017
    Abstract575)   HTML19)    PDF (1970KB)(668)      
    In order to provide decision support for the development planning of residential care facilities, this study investigates spatial distribution and location selection of residential care facilities based on data from care facilities and GIS spatial analytical tools. The results show that existing nursing services can generally meet demands, but there are significant regional differences. Residential care facilities in Shanghai are spatially clustered in the central urban area. Facilities in the city center are adjacent to residential areas and medical institutions; meanwhile, the location of residential care facilities in the suburbs are isolated, probably due to a lack of medical service. Therefore, this paper suggests that the government should provide elderly residents with more nursing support in the suburbs to ensure social equity.
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    Influence of the diversion project and bathymetric change of Ruifeng Shoal on the flow diversion ratios in the South and North Passage of Yangtze River Estuary
    DAO Fu-hai, LUAN Hua-long, YANG Wan-lun, DING Ping-xing, GE Jian-zhong
    Journal of East China Normal University(Natural Sc    2018, 2018 (3): 170-183.   DOI: 10.3969/j.issn.1000-5641.2018.03.018
    Abstract486)   HTML15)    PDF (3122KB)(650)      
    This paper analyzes the bathymetric characteristics and the evolution processes affected by human activities in recent years at the bifurcation of the South and North Passage in the Yangtze River Estuary. A high-resolution FVCOM model is used to investigate the impact of the diversion project, the direction of submerged dike and the bathymetric change of Ruifeng Shoal on the ebb flow diversion ratios of the South and North Passage. The results show that the construction of the submerged dike at the bifurcation head has limited influence on the ebb flow diversion ratio of the North Passage. The ebb flow diversion ratio of the North Passage decreases when the submerged dike deflects northward and vice versa; however, the influence of the southward deflection is greater than that of the northward deflection. Scouring of the middle and lower Ruifeng Shoal and the northward shift of the mainstream are favorable for the flow entering the North Passage, which increases the flow diversion ratio of the North Passage in the upstream cross-section. Due to adjustment of the water flux in HengSha channel, the flow diversion ratio of the North Passage is slightly increased in downstream cross-section.
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    Seicercus affinis and records of eleven other new birds in Shanghai
    SHI Hong-liang, SHI Jian-yong, YUAN Xiao, BO Shun-qi
    Journal of East China Normal University(Natural Sc    2018, 2018 (3): 184-189.   DOI: 10.3969/j.issn.1000-5641.2018.03.019
    Abstract571)   HTML90)    PDF (1157KB)(539)      
    We reported twelve new distribution records of bird species in Shanghai. Nine species, including Seicercus affinis, Abroscopus albogularis, Phylloscopus claudiae, Ficedula elisae, Muscicapa muttui, Turdus mupinensis, Oenanthe deserti, Larus glaucescens, Spilornis cheela, were first recorded in Shanghai. Another three species, Netta rufina, Dendrocitta formosae and Pycnonotus xanthorrhous, that were previously recorded but not listed in the Shanghai Bird List were observed again. All twelve species were considered new records for Shanghai. Thus, a total of 457 bird species, belonging to 20 orders and 70 families, have been now recorded in Shanghai.
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    Additional information on Sphagnaceae species in Xinjiang
    LIU Yan, Winira ILGHAR, Gulnigar AYSIRAHUN, Mamtimin SULAYMAN
    Journal of East China Normal University(Natural Sc    2018, 2018 (3): 190-195,211.   DOI: 10.3969/j.issn.1000-5641.2018.03.020
    Abstract652)   HTML86)    PDF (1159KB)(602)      
    Based on extensive investigation and specimen identification of bryophytes in recent years, four new records of Sphagnaceae species have been reported for Xinjiang Province, namely Sphagnum angustifolium, S.cuspidatulum, S.cuspidatum and S.russowii. The major distinguishing morphological characteristics and geographic distribution of these species are discussed in this paper. The key to species of Sphagnaceae in Xinjiang has been provided. In addition, the geographic distribution of Sphagnaceae in Xinjiang was expanded to include Altai City, Qinghe County, Fuhai County and Habahe County, in addition to Hanas National Nature Reserve in Buerjin County, as previously reported. The results provide additional information on Sphagnaceae for bryoflora of Xinjiang.
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    Progress in development of small molecule inhibitors targeting indoleamine 2,3-dioxygenase
    CHEN Rui, FANG Yan-fen, ZHANG Xiong-wen
    Journal of East China Normal University(Natural Sc    2018, 2018 (3): 196-211.   DOI: 10.3969/j.issn.1000-5641.2018.03.021
    Abstract808)   HTML23)    PDF (1020KB)(1190)      
    In the development of cancer, cancer cells can employ a number of mechanisms to escape detection by the immune system. Indoleamine 2, 3-dioxygenase (IDO) is a type of enzyme in immune cells, which catalyzes the metabolism of tryptophan through the kynurenine pathway. Inflammation induced by cancer development can result in overexpression of IDO in protuberance cells and tumor cells in the tumor microenvironment,causing sustained consumption of tryptophan, inhibition of tryptophan-sensitive T cells functional activity, and a decrease in local immune activity in tumor tissues. Inhibition of IDO activity and its expression could effectively activate the immune system to kill tumor cells. Therefore, IDO has become a new target in cancer immunotherapy. Currently, four IDO inhibitors, namely Epacadostat, Indoximod, GDC-0919 and BMS-986205, are in the clinical research stage as potential new anti-cancer molecule immunotherapy drugs. At the same time, new IDO inhibitors such as PF-06840003 and RG70099 are also being investigated. In this article, the pogress of research on IDO and the development of IDO inhibitors as a new anti-cancer drug for tumor immunotherapy is reviewed.
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    Preliminary study on temporal trend lag of organic pollutant concentrations in environmental media and its influencing factors
    MO Jun-chao, HE Yuan, LIU Gang
    Journal of East China Normal University(Natural Sc    2018, 2018 (3): 212-221.   DOI: 10.3969/j.issn.1000-5641.2018.03.022
    Abstract447)   HTML13)    PDF (442KB)(799)      
    131 organic chemicals were used, and a level IV EQuilibrium Criterion (EQC) multimedia model was built. The model was applied to simulate temporal trends of organic chemical concentrations in environmental media using four emission scenarios. Results showed that temporal trends of organic chemical concentrations lagged behind their emissions in most cases, and organic chemicals with higher lgKOW and persistence showed the most obvious lag effect. Correlation analysis showed that persistence was the principal factor influencing the lag time in water, air, and soil; and lgKOW and persistence were the principal factors in sediment. Prediction formulas for lag time were obtained by regression analysis. If the sediment was a sink of organic chemicals, the lag effect would be distinct.The study can be employed to illustrate the theoretical transfer and transformation of organic chemicals in an environmental system.
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    Spatio-temporal changes of ecological vulnerability in the Jiaozhou Bay Coastal Zone
    PANG Li-hua, KONG Fan-long, XI Min, LI Yue
    Journal of East China Normal University(Natural Sc    2018, 2018 (3): 222-233.   DOI: 10.3969/j.issn.1000-5641.2018.03.023
    Abstract464)   HTML21)    PDF (938KB)(495)      
    Using remote sensing data from 2000 and 2016 in the study area, the temporal and spatial variations of regional ecological vulnerability in the the Jiaozhou Bay Coastal Zone were studied based on landscape ecology and the characteristics of the ecological environment. Models of landscape vulnerabity and land ecological vulnerabity were established by characterizing the number of patches, patch density, reciprocal of fractal dimension, vegetation coverage index, and ecological suitability of land use. The results showed that in the past 16 years, the whole study area was predominantly level one and level two vulnerable areas, among which the proportion of vulnerability reduction was 17.52%. When the ecological vulnerability index of land use in 37.48% of sample areas increased, the land ecological vulnerability also increased. The ranking of overall average ecological vulnerability for all the use types was:other land > cultivated land > forest land > construction land > water area; the stability and anti-interference ability of other land, farmland, and forest land system were weak. The distribution of ecological vulnerabity of land was generally heavy in the Northeast and Southwest, gradually reduced by extension, and conversion between different levels of vulnerability showed significant differences and spatial heterogeneity. In Huangdao District, the area of level one and level three vulnerability changed greatly, while the proportion of level one or level two vulnerable areas decreased. The change of the level two vulnerable areas in Jiaozhou increased the most, and the level one and level two vulnerable areas became the most predominant. The Central district of the city had a lower level of change than other regions. The level five vulnerable areas in Chengyang district increased significantly compared with other regions. These results indicate that population, policy, and social and economic development were the key factors that lead to temporal and spatial variation in the ecological vulnerable areas.
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    Existence of a travelling wave solution for a single population model with spatio-temporal delay
    YANG Gao-xiang, ZHAO Lin-long
    Journal of East China Normal University(Natural Sc    2018, 2018 (4): 1-8.   DOI: 10.3969/j.issn.1000-5641.2018.04.001
    Abstract355)   HTML14)    PDF (352KB)(557)      
    In this paper, the existence of a travelling wave solution for a single population model with spatio-temporal delay is investigated by employing singular perturbation. The theoretical results are validated by using a numerical method. When the time delay is very small, a wave front solution exists; however, as the time delay increases, the shape of this travelling wave solution can vary and an oscillation wake can occur.
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    Spatial Turing pattern of a predator-prey system with nonlinear harvesting effect
    ZHANG Dao-xiang, SUN Guang-xun, HU Wei, KAI Ge
    Journal of East China Normal University(Natural Sc    2018, 2018 (4): 9-22,31.   DOI: 10.3969/j.issn.1000-5641.2018.04.002
    Abstract436)   HTML181)    PDF (2601KB)(755)      
    We study the formation and selection of Turing patterns for a class of predator-prey systems with nonlinear harvesting effect. Firstly, the conditions of Turing instability induced by cross-diffusion terms are given by stability theory, and the existence region of Turing patterns of the system are obtained by bifurcation theory. Secondly, the amplitude equations of the system are derived using the multi-scales analysis method, and the selection results of Turing patterns are given. Finally, Matlab is used to simulate the pattern formation and selection results of the system. The results show that the system has rich Turing patterns, such as spot, stripe, and coexistence of the two types.
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    Two optimal inequalities for Neuman-Sándor means
    YANG Yue-ying, MA Ping
    Journal of East China Normal University(Natural Sc    2018, 2018 (4): 23-31.   DOI: 10.3969/j.issn.1000-5641.2018.04.003
    Abstract402)   HTML11)    PDF (252KB)(602)      
    This paper deals with the inequalities involving Neuman-Sándor means using methods of real analysis. The convex combinations of the second contra-harmonic mean D(a, b) and the harmonic root-square mean H(a, b) (or harmonic mean H(a,b)) for the Neuman-Sándor mean M(a, b) are discussed. We find the maximum values λ1, λ2 ∈ (0, 1) and the minimum values μ1, μ2 ∈ (0, 1) such that the two-sided inequalities
    λ1D(a, b) + (1-λ1)H(a, b) < M(a, b) < μ1D(a, b) + (1-μ1)H(a, b),
    λ2D(a, b) + (1-λ2)H(a,b) < M(a, b) < μ2D(a, b) + (1-μ2)H(a,b)
    hold for all a, b > 0 with ab.
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    The skew-Hermitian {P,k+1} Hamiltonian solutions of a linear matrix equation
    YONG Jin-jun, CHEN Guo-liang, XU Wei-ru
    Journal of East China Normal University(Natural Sc    2018, 2018 (4): 32-46,58.   DOI: 10.3969/j.issn.1000-5641.2018.04.004
    Abstract476)   HTML9)    PDF (414KB)(530)      
    Given PCn×n and P*=-P=P k+1, we consider the necessary and sufficient conditions such that the matrix equation AX=B is consistent with the skew-Hermitian {P, k + 1} (skew-) Hamiltonian structural constraint. Then, the corresponding expressions of the constraint solutions are also obtained. For any given matrix à ∈ Cn×n, we present the optimal approximate solution ā ∈ Cn×n such that ||Ã-ā|| is minimized in the Frobenius norm sense. If the matrix equation AX=B is not consistent, its least-squares skew-Hermitian {P, k + 1} (skew-) Hamiltonian solutions are given. Under the least-square sense, we consider the best approximate solutions to any given matrix. Finally, some illustrative experiments are also presented.
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    Pricing of lookback options under a mixed fractional Brownian movement
    CHEN Hai-zhen, ZHOU Sheng-wu, SUN Xiang-yan
    Journal of East China Normal University(Natural Sc    2018, 2018 (4): 47-58.   DOI: 10.3969/j.issn.1000-5641.2018.04.005
    Abstract419)   HTML6)    PDF (589KB)(493)      
    This paper studied the pricing of European lookback options when the underlying asset followed a mixed fractional Brownian movement and the transaction costs were considered. Firstly, the nonlinear partial differential equation and its boundary condition were obtained using the hedging principle under the model. Secondly, the partial differential equation was reduced using variable substitution. Next, we found its numerical solution by constructing a Crank-Nicolson format. Lastly, the convergence of the numerical scheme was discussed. We also discussed the influence of the transaction fee ratio, Hurst index, and so on.
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    A strategy for real-time trajectory privacy protection
    LIAO Chun-he, HUA Jia-xun, TIAN Xiu-xia, QIN Bo, JIN Che-qing
    Journal of East China Normal University(Natural Sc    2018, 2018 (4): 59-69,108.   DOI: 10.3969/j.issn.1000-5641.2018.04.006
    Abstract490)   HTML11)    PDF (1956KB)(664)      
    Real-time trajectory privacy protection is a key research topic in the field of location-based services (LBS). Dummy trajectory technology is a popular privacy protection method which generates multiple fake trajectories similar to real ones. However, existing schemes take into account neither the real environment nor the relationship between adjacent positions carefully; with the help of this ancillary information, the real trajectory can be inferred easily. Hence we integrate entropy and constraints on location reachability into our proposed schemes, named dummy-based trajectory generating (DTG) and enhanced-DTG (EnDTG). Experimental results show that both schemes offer a higher privacy level than existing ones.
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    An algorithm for natural language generation via text extracting
    AI Li-si, TANG Wei-hong, FU Yun-bin, DONG Qi-min, ZHENG Jian-bing, GAO Ming
    Journal of East China Normal University(Natural Sc    2018, 2018 (4): 70-79.   DOI: 10.3969/j.issn.1000-5641.2018.04.007
    Abstract493)   HTML76)    PDF (922KB)(598)      
    The aim of natural language generation is to achieve a state where machines can generate text automatically. This would reduce the workload of human language workers and helps us deliver real-time, concise news coverage to readers. It could be applied to many applications, such as question and answers systems, automatic news writing, incident reporting, and so on. The challenge has been one of the open problems for both academia and industry. In this paper, we model the issue as a keyword covering problem and propose an unsupervised approach to extract text for natural language generation.The experimental results illustrate that the algorithm is effective for large-scale corpus; the text coverage is more comprehensive and the generated text is closer to the manual text produced by an individual.
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    Incorporating Bayesian inference with random walk for friend recommendations
    YANG Qing, WANG Hai-yang, BIAN Meng-yang, ZHANG Jing-wei, LIN Yu-ming, ZHANG Hui-bing, ZHANG Hai-tao
    Journal of East China Normal University(Natural Sc    2018, 2018 (4): 80-89.   DOI: 10.3969/j.issn.1000-5641.2018.04.008
    Abstract443)   HTML9)    PDF (643KB)(527)      
    Random walk is an effective strategy for dealing with a large user base as well as data sparsity in recommendation problems. However, the current work on recommendation problems do not take full account of the impact implied by both the intimacy difference between users and the reverse social influence. This paper presents an optimized friend recommendation model based on random walk, which introduces frequent pattern mining to capture user intimacy and to optimize the transition probability matrix,and is combined with local reverse search to implement recommendations. In order to make full use of users' attribute information, a Bayesian inference model is proposed for analyzing users' potential friend relationships and combined with random walk to provide better recommendation services. Experiments on real datasets demonstrated the effectiveness of the proposed method.
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    Sublink elimination and optimization in data storage and processing separation architecture
    WANG Yan-zhao, HU Hui-qi, ZHANG Zhao, LIU Xiao-bing, DUAN Hui-chao
    Journal of East China Normal University(Natural Sc    2018, 2018 (4): 90-98.   DOI: 10.3969/j.issn.1000-5641.2018.04.009
    Abstract375)   HTML12)    PDF (741KB)(453)      
    This paper implemented a sublink elimination optimizer in NewSQL RDBMS (Relational Database Management System). The purpose of the optimizer is to make complex SQL so that it can be executable in New SQL systems, and achieve auto-tuning of complex SQL to reduce the cost of migrating from a centralized database to a distributed database; this would make the NewSQL DBMS (Database Management System) available to telecomunications and banking industries. We also provide a method to minimize data transmission between servers after sublink promotion. Experiments show that the optimization effect of the query optimizer is notable and can replace manual optimization and reduce the workload of application migration.
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    Data calculation and performance optimization of dairy traceability based on Hadoop/Hive
    ZHU Shu-xin, LI Yue, YUAN Pei-sen, XU Huan-liang, WANG Kang, XIE Zhong-hong
    Journal of East China Normal University(Natural Sc    2018, 2018 (4): 99-108.   DOI: 10.3969/j.issn.1000-5641.2018.04.010
    Abstract456)   HTML20)    PDF (1550KB)(517)      
    In order to enhance the performance of traditional dairy traceability systems for the production data of large-scale enterprise, this paper analyzed the supply chain process of dairy enterprises, key traceability units and traceability information; combining Hadoop/Hive big data technology and distributed database technology, the paper designed and constructed a dairy products traceability framework based on Hadoop/Hive. We built a simulated large-scale data environment and used actual production data to test the system performance. The experimental results showed that after the introduction of the Hadoop/Hive technology system, the average data storage speed, the average data access speed, and the average data exchange rate increased by 87.43%, 27.10% and 58.16%, respectively. The improved traceability system for dairy products is superior to the traditional dairy traceability system in storing and processing large-scale data.
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    High performance computing in quantum chemistry
    WANG Tao
    Journal of East China Normal University(Natural Sc    2018, 2018 (4): 109-119.   DOI: 10.3969/j.issn.1000-5641.2018.04.011
    Abstract447)   HTML20)    PDF (402KB)(674)      
    High performance computing is widely used for chemical simulations. This paper reviews the current state of parallel computation methods in quantum chemistry; discusses the features, software technology and parallel implements of various quantum chemistry methods; and considers the prospects for the future.
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    Collaborative filtering recommendation algorithm based on the self-similarity matrix
    ZHANG Wei, ZHENG Jun, PANG Jiao-na, BAI Yue
    Journal of East China Normal University(Natural Sc    2018, 2018 (4): 120-128,146.   DOI: 10.3969/j.issn.1000-5641.2018.04.012
    Abstract411)   HTML11)    PDF (721KB)(563)      
    A collaborative filtering recommendation algorithm based on self-similar matrices is put forward for the noise problem in the proposed system. In this paper, self-similar matrices are selected as primitive matrices, and the sliding window is chosen as the row vector and column vector of the score. The new score matrix is obtained to preprocess the original scoring matrix to establish the linear relationship between the scoring value and the self-similar matrices. The new scoring matrix preserves the original matrix of scoring information, while weakening the impact of noise data on the recommended system. Experiments show that the pre-processing of the original matrix effectively alleviates the impact of noise in the scoring matrix and improves the performance of the proposed system.
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    A study of approximate analytical solutions of a kind of typical second-order nonlinear different equation
    LOU Zhi-mei, WANG Yuan-bin, WANG Peng
    Journal of East China Normal University(Natural Sc    2018, 2018 (4): 129-137.   DOI: 10.3969/j.issn.1000-5641.2018.04.013
    Abstract523)   HTML12)    PDF (329KB)(560)      
    In a non-inertial rotational reference frame, the motion of a system can be governed by a kind of second-order nonlinear differential equation, in which the numerator and denominator both contain nonlinear terms; in this context, it is hard to obtain an approximate solution for this strongly nonlinear equation. In this paper, we study the approximate solution of the second-order nonlinear differential equation by the Adomian decomposition method. Comparisons between the approximate solution and the numerical solution by using two other methods are also made. The results show that, in the first quarter period, the approximate solutions obtained by the Adomian decomposition method is in good agreement with the numerical solutions and the error of the approximate solutions are smaller than the other solutions obtained by the homotopy asymptotic method.
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    Study and investigation of Lejeuneaceae species diversity in Anhui Province
    SHI Xue-qin, TANG Xia, WEI Yu-mei, WANG Jian
    Journal of East China Normal University(Natural Sc    2018, 2018 (4): 138-146.   DOI: 10.3969/j.issn.1000-5641.2018.04.014
    Abstract486)   HTML9)    PDF (466KB)(527)      
    This paper studies the diversity of Lejeuneaceae species in Anhui Province based on field data collections and literature review. Our study reveals the occurrence of 46 species in 11 genera of Lejeuneaceae in Anhui Province, including one newly recorded genus (Myriocoleopsis Schiffn.) and 10 newly recorded species. The genus with the largest number of species is Lejeunea (12 spp.) and the second largest genus is Cololejeunea (10 spp.). Floristic analysis shows that tropical elements are the most prevalent among Anhui Lejeuneaceae flora with 27 species, accounting for approximately 58.7% of the Lejeuneaceae species in Anhui Province. East Asian elements, the second most prevalent group, with 13 species accounts for approximately 28.3% of the total number of species. The optimal habitat conditions for most Lejeuneaceae are low mountainous and ravine areas below 400 m as well as alpine areas above 1 600 m. Four epiphyllous liverwort species are newly reported from Guniujiang Nature Reserve in Shitai County. The distribution of epiphyllous liverworts in Eastern China therefore extends north of latitude 30°N. We also analyzed the status of epiphyllous liverworts in this area.
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    A study on spatial-temporal differences and factor decomposition of the ecological footprint of Zhejiang Province
    LI Guo-zhi
    Journal of East China Normal University(Natural Sc    2018, 2018 (4): 147-158.   DOI: 10.3969/j.issn.1000-5641.2018.04.015
    Abstract382)   HTML9)    PDF (553KB)(544)      
    Using an ecological footprint model, this paper calculated the ecological footprint and ecological carrying capacity of Zhejiang Province, and further decomposed the ecological footprint using an IPAT model. The results showed that the ecological footprint increased from 7.852×107 ghm2 to 1.5484×108 ghm2 from 2002 to 2015, and that the ecological pressure was significant. At the same time, the ecological efficiency improved rapidly, and the capacity for economic sustainable development improved. The ecological footprint and ecological carrying capacity varied greatly in different regions. Lishui City was the only region with ecological surplus; the ecological efficiency was 1.04×104 yuan/ghm2 in 2015, the highest among all the regions in Zhejiang Province. The results of factor decomposition showed that economic growth was the inhibiting factor for the ecological footprint, and it reduced the ecological footprint to 8.164×107 ghm2 across the whole province. The level of economic development and population size were driving factors, and they increased the ecological footprint by 1.2987×108 ghm2 and 2.810×107 ghm2, respectively, across the whole province.
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    Dynamic characteristics and influencing mechanisms of suspended sediment discharge at the outlet of Dongting Lake
    YU Ya-wen, DAI Zhi-jun, MEI Xue-fei, WANG Jie, WEI Wen
    Journal of East China Normal University(Natural Sc    2018, 2018 (4): 159-170.   DOI: 10.3969/j.issn.1000-5641.2018.04.016
    Abstract514)   HTML13)    PDF (2788KB)(493)      
    Dongting Lake's storage capacity is of vital significance to the Changjiang River. The changes in suspended sediment discharge (SSD) from Dongting Lake to the Changjiang River are closely linked to both the lake's evolution and the lake-river relationship. Based on long-term hydrologic data from 1951-2015, the dynamic characteristics of SSD at theDongting Lake outlet and associated controlling factors were analyzed by using percentile, coefficient of variation, and wavelet analysis. The results showed that the SSD time series (1951-2015) could be divided into three sub-periods, namely 1951-1970,1971-2002, and 2003-2015. Specifically, SSD of the first two periods exhibited decreasing trends, while SSD during the 2003-2015 period displayed on upward tendency. Apparent seasonal fluctuations were observed in SSD with a majority of sediment transported in March-December and in March-August during 1951-1970 and 1971-2015, respectively. However, the peak monthly SSD shifted from April in 1951-2002 to May in 2003-2015. Moreover, periodic 44-year and 24-year oscillations were detected across the entire SSD data set. The variation in SSD at the outlet of Dongting Lake can be explained by runoff, water conservancy projects, and the lake's erosion-deposition pattern. It was found that runoff at the outlet of Dongting Lake was the important factor induced the seasonal fluctuation and primary periodic oscillation of SSD. The Jingjiang Cut-off Project is likely responsible for the significant SSD decrease during the period 1971-2002. Annual average SSD over the period 2003-2015 decreased by 30.1% in comparison with 1971-2002 following opening of the Three Gorges Dam. In addition, the SSD series showed an increasing trend after 2007 as the Dongting Lake basin shifted from a deposition state into an erosion state.
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    Water mass transport and its controlling mechanisms between the Changjiang Estuary and Subei Coastal Water during the summer
    ZHU Ping, WU Hui
    Journal of East China Normal University(Natural Sc    2018, 2018 (4): 171-183.   DOI: 10.3969/j.issn.1000-5641.2018.04.017
    Abstract455)   HTML13)    PDF (2153KB)(550)      
    The objective of this study was to investigate summertime water movement and its response to wind and tidal forces between the Changjiang Estuary and the Subei coastal area based on a high-resolution, three-dimensional numerical model. The volumetric flux and the freshwater transport from the Changjiang River and the Subei local rivers were quantified across a number of cross-shelf sections. The results indicated that, under the studied climatologic conditions, the net transport in the Subei Coastal Water is generally northward. The velocity of this northward transport reaches 10 cm/s in the shallow area. Offshore transport occurs in the vicinity of the Sheyang Estuary, with a net transport velocity of circa 7 cm/s along the 40 m isobaths. The sectional water flux is related to the tidal range, which reaches a low point in neap tide and a high point in spring tide, respectively. The tide has great impact on water movement in this area. Without the tide, the net water transport is entirely northward north of the Changjiang River Estuary and the southeastward transport along the 40 m isobaths vanishes. On the other hand, the monsoon has no significant influence on the water movement; it only adjusts the water transport in a few local areas.
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    Characteristics of sea surface temperature in the Changjiang Estuary and adjacent waters based on a Self-Organizing Map
    BAI Mei, WU Hui
    Journal of East China Normal University(Natural Sc    2018, 2018 (4): 184-194.   DOI: 10.3969/j.issn.1000-5641.2018.04.018
    Abstract410)   HTML22)    PDF (1860KB)(563)      
    Sea surface temperature (SST) in the Changjiang Estuary and adjacent waters is affected by multiple dynamic processes, which show complex spatiotemporal variability. In this study, the SST variability was investigated by analyzing modeled results with a Self-Organizing Map (SOM) method. The SST variations were clustered on seasonal, spring-neap, and intra-tidal timescales. It was found that the SST pattern remains stable during the winter and summer seasons but highly variable during the spring and autumn seasons. A cold water band is present south of the Changjiang River mouth in the winter season, due to the southward along-shore extension of the Changjiang River plume. A cold water patch occurs near the Zhoushan Islands, caused by upwelling in the Zhejiang coastal water. In the Subei coastal water, the cold water patch and tongues were most significant during the winter and spring seasons.
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    Journal of East China Normal University(Natural Sc    2018, 2018 (5): 1-2.  
    Abstract240)   HTML167)    PDF (266KB)(1244)      
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    Journal of East China Normal University(Natural Sc    2018, 2018 (5): 1-1.  
    Abstract143)   HTML67)    PDF (188KB)(425)      
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    Survey on scene text detection based on deep learning
    YU Ruo-nan, HUANG Ding-jiang, DONG Qi-wen
    Journal of East China Normal University(Natural Sc    2018, 2018 (5): 1-16.   DOI: 10.3969/j.issn.1000-5641.2018.05.001
    Abstract511)   HTML75)    PDF (3451KB)(957)      
    With improvements in computer hardware performance, object detection, and image segmentation algorithms (based on deep learning) have broken the bottlenecks posed by traditional algorithms in big data-driven applications and become the mainstream algorithms in the field of computer vision. In this context, scene text detection algorithms have made great breakthroughs in recent years. The objectives of this survey are three-fold:introduce the progress of scene text detection over the past 5 years, compare and analyze the advantages and limitations of advanced algorithms, and summarize the relevant benchmark datasets and evaluation methods in the field.
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    A review of non-intrusive sensing based personalized resource recommendations for help-seekers in education
    TANG Lu-min, YU Ruo-nan, DONG Qi-wen, HONG Dao-cheng, FU Yun-bin
    Journal of East China Normal University(Natural Sc    2018, 2018 (5): 17-29.   DOI: 10.3969/j.issn.1000-5641.2018.05.002
    Abstract440)   HTML8)    PDF (1505KB)(505)      
    Mobile devices, data storage, and computing platforms of modern information technology have accelerated the integration of the information technology and education disciplines, promoted the "Education Informatization 2.0" Plan, and provided a solid technical foundation for academic help-seeking. With the help of new sensing mechanisms and techniques, non-intrusive sensing of help-seeking and personalized recommendation methods can now be used for teaching practices in academia. This study reviews the research progress of non-intrusive sensing based personalized resource recommendations, offers detailed analysis, and lists possible directions for research; potential future research topics include non-intrusive sensing for help-seeking, continuous association analysis and integration for multidimensional data, and personalized resource recommendations for help-seekers. This study also makes contributions to precision education and personalized education for the China Education Informatization 2.0 Plan by providing solutions for non-intrusive sensing based personalized resource recommendations for help-seekers.
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    Data processing software technology for new hardware
    TU Yun-shan, CHU Jia-jia, ZHANG Yao, WENG Chu-liang
    Journal of East China Normal University(Natural Sc    2018, 2018 (5): 30-40,78.   DOI: 10.3969/j.issn.1000-5641.2018.05.003
    Abstract553)   HTML13)    PDF (978KB)(1573)      
    The rapid development of computer hardware in recent years has brought profound technological progress. New hardware for high-performance and low-latency applications (e.g., heterogeneous processors, programmable high-speed NICs/switches, and volatile/non-volatile memory) have been emerging, which bring both new opportunities and challenges to traditional computer architectures and systems. In the case of big data processing, it is difficult to adapt traditional software technology directly onto new hardware, this makes realizing the full potential brought by breakthroughs in hardware technology challenging. Hence, a rethink of traditional software technology can help unlock the benefits brought by advancements in hardware technology. This paper reviews:data processing technology for new hardware from the perspective of computing, transmission, and storage; an analysis of related work in the field; a summary of progress made to date; and new problems and challenges that exist. The study also provides a valuable reference point for future research on exploring the performance ceiling of systems for data processing.
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    A survey of entity matching algorithms in heterogeneous networks
    LI Na, JIN Gang-zeng, ZHOU Xiao-xu, ZHENG Jian-bing, GAO Ming
    Journal of East China Normal University(Natural Sc    2018, 2018 (5): 41-55.   DOI: 10.3969/j.issn.1000-5641.2018.05.004
    Abstract468)   HTML13)    PDF (2253KB)(729)      
    The continuous integration of Internet, Internet of Things, and cloud computing technologies has been improving digitization across different industries, but it has also introduced increased data fragmentation. Data fragmentation is characterized by mass, heterogeneity, privacy, dependence, and low quality, resulting in poor data availability. As a result, it is often difficult to obtain accurate and complete information for many analytical tasks. To make effective use of data, entity matching, fusion, and disambiguation are of particular significance. In this paper, we summarize data preprocessing, similarity measurements, and entity matching algorithms of heterogeneous networks. In addition, particularly for large datasets, we investigate scalable entity matching algorithms. Existing entity matching algorithms can be categorized into two groups:supervised and unsupervised learning-based algorithms. We conclude the study with research progress on entity matching and topics for future research.
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    Implementation of the parallel GroupBy and Aggregation functions in a distributed database system
    XU Shi-lei, WEI Xing, JIANG Hong, QIAN Wei-ning, ZHOU Ao-ying
    Journal of East China Normal University(Natural Sc    2018, 2018 (5): 56-66.   DOI: 10.3969/j.issn.1000-5641.2018.05.005
    Abstract499)   HTML11)    PDF (1950KB)(656)      
    With the increase in demand for data statistics and analysis in new Internet applications, data grouping and aggregation have become amongst the most common operations in data analysis applications. This paper analyzes the operating principles of the Aggregation and GroupBy functions commonly used in analytical applications. Based on the disadvantages of sort grouping for general-transactional databases, two kinds of Hash GroupBy implementations are proposed; in addition,a strategy for dynamically determining the number of Hash buckets and Hash GroupBy schemes, based on statistical information, is proposed. Based on the characteristics of distributed clusters, implementation of the Hash GroupBy operator push down is proposed. Experiments have shown that the use of statistical information to dynamically determine the Hash group option improves efficiency.
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    The designs and implementations of columnar storage in Cedar
    YU Wen-qian, HU Shuang, HU Hui-qi
    Journal of East China Normal University(Natural Sc    2018, 2018 (5): 67-78.   DOI: 10.3969/j.issn.1000-5641.2018.05.006
    Abstract443)   HTML11)    PDF (1692KB)(645)      
    With the growing size of data and analytical needs, the query performance of databases for OLAP (On-Line Analytical Processing) applications has become increasingly important. Cedar is a distributed relational database based on read-write decoupled architecture. Since Cedar is mainly oriented to the needs of OLTP (On-Line Transaction Processing) applications, it has insufficient performance for handling analytical processing workloads. To address this issue, many studies have shown that column storage technology can effectively improve the efficiency of I/O (Input/Output) and enhance the performance of analytical processing. This paper presents a column-based storage mechanism in Cedar. The study analyzes applicable scenarios and improves Cedar's data query and batch update methods for this mechanism. The results of an experiment demonstrate that the proposed mechanism can enhance the performance of analytical processing substantially, while limiting the negative impacts on transaction processing performance to within 10%.
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    Primary key management in distributed log-structured database systems
    HUANG Jian-wei, ZHANG Zhao, QIAN Wei-ning
    Journal of East China Normal University(Natural Sc    2018, 2018 (5): 79-90,119.   DOI: 10.3969/j.issn.1000-5641.2018.05.007
    Abstract1113)   HTML11)    PDF (1197KB)(465)      
    At present, there are a large number of writing-intensive loads (e.g., secondkilling of e-commerce, social user-generated data streams) in many applications such as e-commerce, social networking, mobile Internet and so on, which makes log-structured storage a popular technique for back-end storage of modern database systems. However, log-structured storage only supports the append operation, efficient primary key management (primary key generation and update) functions can improve the performance of database append operations. In the distributed and concurrent environment, implementing primary key maintenance faces challenges, such as primary key unique constraints, transactional maintenance, and high-performance requirements. In light of the characteristics of log-structured storage, this paper explores how to implement efficient primary key management in distributed log-structured database systems. First, we propose two kinds of concurrency control models for WAR (Write After Read) operations; second, we adopt these two models to design efficient primary key management algorithms; and finally, we integrate these algorithms into our distributed log-structured database, CEDAR, and verify the effectiveness of the proposed methods by a series of experiments.
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    Application of the consistency protocol in distributed database systems
    ZHAO Chun-yang, XIAO Bing, GUO Jin-wei, QIAN Wei-ning
    Journal of East China Normal University(Natural Sc    2018, 2018 (5): 91-106.   DOI: 10.3969/j.issn.1000-5641.2018.05.008
    Abstract515)   HTML10)    PDF (1419KB)(528)      
    In recent years, many distributed database products have emerged in the market; yet, distributed databases are still more complex than centralized databases. In order to make the system useable, designers need to adopt the consistency protocol to ensure two important features of distributed database systems:availability and consistency. The protocol ensures consistency by determining the global execution order of operations for concurrent transactions and by coordinating local and global states to achieve continuous dynamic agreement; The consistency protocol ensures availability by coordinating consistency between multiple copies to achieve seamless switching between master and standby nodes. Hence, the distributed consensus protocol is the fundamental basis for the distributed database system. This paper reviews, in detail, the classic distributed consistency protocol and the application of the consistency protocol to current mature distributed database. The study also provides analysis and a comparison between the two approaches considering factors like read-write operation, node type, and network communication.
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    Technology and implementation of a new OLTP system
    HE Xiao-long, MA Hai-xin, HE Yu-kun, PANG Tian-ze, ZHAO Qiong
    Journal of East China Normal University(Natural Sc    2018, 2018 (5): 107-119.   DOI: 10.3969/j.issn.1000-5641.2018.05.009
    Abstract533)   HTML11)    PDF (1174KB)(518)      
    Since the 1970s, there has been considerable progress in hardware development; in particular, high-performance servers are now equipped with TB-level memory capacity and dozens of physical cores. Traditional OLTP systems, however, are still based on disk storage and designed for hardware with a small number of physical cores; hence, these systems are unable to effectively and fully exploit the computing power offered by new hardware. With the development of the Internet, applications commonly have high performance requirements for transactional systems. In extreme cases, some applications service millions of concurrent access requests, which traditional database systems cannot satisfy. Hence, the redesign and implementation of a transactional database system on high performance hardware has become an important research topic. In this study, we focused on recent work on transaction database systems on large memory and multi-core environments. We used OceanBase, an open source database developed by Alibaba, as an example to analyze the design of a new OLTP system.
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    Distributed spatio-textual analytics based on the Spark platform
    XU Yang, WANG Zhi-jie, QIAN Shi-you
    Journal of East China Normal University(Natural Sc    2018, 2018 (5): 120-134,153.   DOI: 10.3969/j.issn.1000-5641.2018.05.010
    Abstract336)   HTML9)    PDF (1180KB)(502)      
    With the rapid development of location-based services, spatio-textual data analytics is becoming increasingly important. For instance, it is widely used in social recommendation applications. However, performing efficient analysis on large spatio-textual datasets in a central environment remains a big challenge. This paper explored distributed algorithms for spatio-textual analytics based on the Spark platform. Speciffically, we proposed a scalable two-level index framework, which processes spatio-textual queries in two steps. The global index is highly scalable and it can retrieve candidate partitions with only a few false positives. The local index is designed based on pruning ability of infrequent keywords and used for each candidate partition. We implemented the proposed distributed algorithms in Spark. Extensive experiments demonstrated promising performance for the proposed solution.
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    Blockchain-based smart meter authentication scheme
    TIAN Fu-liang, TIAN Xiu-xia, CHEN Xi
    Journal of East China Normal University(Natural Sc    2018, 2018 (5): 135-143,171.   DOI: 10.3969/j.issn.1000-5641.2018.05.011
    Abstract586)   HTML93)    PDF (1326KB)(594)      
    The development of power networks is a trend of the future. These networks allow the two-way flow of power resources between users and power systems. As the key node for connecting users and energy systems, smart meters contain a large volume of user's power transaction data and identity information, which leaves the potential for a breach of private user data. To protect the privacy of the user, an identity authentication scheme for smart meters, based on blockchain technology, is proposed. The smart meter's identity information is processed using the Merkle-tree principle and stored in the blockchain; with this, the authentication of the smart meter's identity is realized and the identity information cannot be modified. Additionally, it breaks the connection between the user's identity and their power data, preventing internal and external hackers from obtaining private user data. The integrity and validity of the transaction data are guaranteed by using the characteristics of blockchain technology.
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    A warehouse receipt management system based on blockchain technology
    QI Xue-cheng, ZHU Yan-chao, SHAO Qi-feng, ZHANG Zhao, JIN Che-qing
    Journal of East China Normal University(Natural Sc    2018, 2018 (5): 144-153.   DOI: 10.3969/j.issn.1000-5641.2018.05.012
    Abstract1367)   HTML121)    PDF (2297KB)(814)      
    Currently, the authenticity of warehouse receipts requires endorsement by a third party in the warehouse receipt e-business. However, fraud cases where receipts are repeatedly pledged often occur, causing huge losses to the country. The data, moreover, is often centrally managed and unavailable to the public, making it difficult to trace records for goods. To solve these problems, this paper designs and implements a warehouse receipt management system, based on blockchain technology, which offers a high degree of transparency, decentralization, trust, and an unchangeable historical record. The system can ensure the accuracy and authenticity of the warehouse receipt. The paper builds an inverted index structure on the blockchain system to improve the efficiency of queries and also support complex queries. The paper proposes a REST(Representational State Transfer)-based service architecture, which provides a flexible, multiple access interface, making it easy to integrate with existing systems and provide support for the development of web and mobile applications.
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    Optimization of the Levenshtein algorithm and its application in repeatability judgment for test bank
    ZHANG Heng, CHEN Liang-yu
    Journal of East China Normal University(Natural Sc    2018, 2018 (5): 154-163.   DOI: 10.3969/j.issn.1000-5641.2018.05.013
    Abstract440)   HTML13)    PDF (1017KB)(467)      
    In order to overcome the disadvantages of the Levenshtein distance algorithm for long text and large-scale matching, we propose an early termination strategy for the Levenshtein distance algorithm. Firstly, according to the intrinsic relationship between elements in the Levenshtein distance matrix, we sum up a recurrence relation. Based on this relation, an early termination strategy is proposed to determine early-on whether two texts satisfy the predefined similarity threshold. Through several tests on different subjects, it is demonstrated that the early termination strategy can significantly reduce calculation time.
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    A K-Means based clustering algorithm with balanced constraints
    TANG Hai-bo, LIN Yu-ming, LI You
    Journal of East China Normal University(Natural Sc    2018, 2018 (5): 164-171.   DOI: 10.3969/j.issn.1000-5641.2018.05.014
    Abstract454)   HTML15)    PDF (932KB)(608)      
    Clustering is a type of core data processing technology, which has been applied widely in various applications. Traditional clustering algorithms, however, cannot guarantee the balance of clustering results, which is inconsistent with the needs of real-world applications. To address this problem, this paper proposes a K-Means based clustering algorithm with balanced constraints. The proposed clustering algorithm changes the data point assignment process, in each iteration, to achieve balanced data blocks. The maximum cluster size threshold can be customized to meet different division requirements. The algorithm is simple and efficient-only two parameters need to be specified:the number of clusters and the threshold for the maximum cluster size. A series of experiments carried on six real UCI (University of California Irvine) datasets show that the algorithm proposed in this paper has better clustering performance and efficiency compared to other balanced clustering algorithms.
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    Research on trademark image retrieval based on deep Hashing
    YUAN Pei-sen, ZHANG Yong, LI Mei-ling, GU Xing-jian
    Journal of East China Normal University(Natural Sc    2018, 2018 (5): 172-182.   DOI: 10.3969/j.issn.1000-5641.2018.05.015
    Abstract554)   HTML90)    PDF (1654KB)(634)      
    Large-scale image retrieval has great potential for a vast number of applications. The fundamentals of image retrieval lie in image feature extraction and high-efficiency similarity evaluation. Deep learning has great capability for feature representation in image objects, while the Hashing technique has better efficiency for high-dimensional data approximation queries. At present, hash learning technology has been widely researched and applied in large-scale image retrieval for the similarity query. This paper extracts trademark image features using convolutional neural network techniques; the data objects are then encoded with bit codes and an approximate query is applied in Hamming space with high efficiency. In this paper, the convolutional neural network is employed and a deep learning based Hash algorithm is proposed; in addition, the loss function and optimizer for the trademark dataset are studied. By obtaining the bit codes that satisfy the Hash coding criterion, the retrieval of trademark data is efficient. Our method can be divided into offline deep Hash learning and online query stages. Experiments are conducted on real trademark data sets, and the results show that our method can obtain high-quality bit code, which has high retrieval accuracy and online query efficiency.
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    Extraction of social media data based on the knowledge graph and LDA model
    MA You, YUE Kun, ZHANG Zi-chen, WANG Xiao-yi, GUO Jian-bin
    Journal of East China Normal University(Natural Sc    2018, 2018 (5): 183-194.   DOI: 10.3969/j.issn.1000-5641.2018.05.016
    Abstract490)   HTML21)    PDF (1117KB)(711)      
    Social media data extraction forms the basis of research and applications related to public opinion, news dissemination, corporate brand promotion, commercial marketing development, etc. Accurate extraction results are critical to guarantee the effectiveness of the data analysis. In this paper, we analyze the underlying topics in data based on the LDA (Latent Dirichlet Allocation) model; we further implement data extraction in specific domains by adopting featured word sequences and knowledge graphs that describe entities and relevant relationships. Experimental results using "Headline Today" news and Sina Weibo data show that our proposed method can be used to extract social media data effectively.
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    Journal of East China Normal University(Natural Sc    2018, 2018 (6): 1-1.  
    Abstract188)   HTML19)    PDF (192KB)(467)      
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    Aerobic denitrifiers and the state of research in their use for sewage treatment and environmental remediation
    DING Yu, ZHANG Ting-yue, HUANG Min-sheng, HE Yan, CAO Cheng-jin
    Journal of East China Normal University(Natural Sc    2018, 2018 (6): 1-11,67.   DOI: 10.3969/j.issn.1000-5641.2018.06.001
    Abstract436)   HTML166)    PDF (1037KB)(533)      
    The use of aerobic denitrifying bacteria has introduced a new concept to traditional biological nitrogen removal given its unique advantages for simultaneous nitrification and denitrification. This paper reviewed the separation methods of aerobic denitrifiers as well as their respective types and influencing factors. The mechanism of aerobic denitrification is explored from the perspective of electron transfer bottleneck theory and enzymology; meanwhile, the applications for wastewater treatment and environmental remediation are also introduced. Studies have shown that:temperature, dissolved oxygen (DO), carbon source, the carbon to nitrogen ratio, and pH value all have effects on the aerobic denitrification process; and aerobic denitrifying bacteria have efficient nitrogen removal efficiency under suitable conditions. However, at present, aerobic denitrifying bacteria still have insufficient impact for environmental remediation applications. There is a gap between laboratory results and engineering applications, so further investigation is needed. This paper systematically summarizes the separation methods, types, reaction mechanisms, influencing factors, and applications of aerobic denitrifying bacteria in wastewater treatment and environmental remediation.
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    Experimental study on a new enhanced in-situ denitrification device for upgrading domestic wastewater treatment plants
    CUI He, YANG Yin-chuan, HUANG Min-sheng, YANG Le, YIN Chao, HE Yan, CAO Cheng-jin
    Journal of East China Normal University(Natural Sc    2018, 2018 (6): 12-21.   DOI: 10.3969/j.issn.1000-5641.2018.06.002
    Abstract411)   HTML8)    PDF (1328KB)(483)      
    To effectively strengthen the nitrogen removal efficiency of wastewater treatment plants (WWTPs), a novel deep denitrification device (Tubular bio-reactor device, TBD) was developed. Four kinds of solid materials (loofah, palm fiber, bagasse, and fibrous fillers) were used as fillers for the TBD. The best filler type was determined by comparing the denitrification performance of TBDs with different fillers. Then, high-throughput sequencing results of the matrix biofilm were used to analyze the denitrification mechanism. The results showed that the best removal rate of nitrogen from water was achieved with the TBD filled with bagasse. For this TBD, the removal rates of NH4+-N, NO3--N, NO2--N and TN were 72%, 64%, 97%, and 82%, respectively, and NH4+-N and TN concentrations both attained Grade 1-A of the Chinese-National discharge standard for WWTPs (GB 18918-2002). TBD filled with bagasse had a high abundance and diversity of microbial species with a Chao1 index of 9 743.55 and a Shannon index of 6.37, and the denitrification-related genus in the microbial community structure was dominant (23.75%). In addition, nitrification (7.73%) and anaerobic ammonium oxidation (2.0%) related genera were detected in the biofilm sample. The results suggest that the internal environment of TBD filled with "bagasse" was good for the enrichment and growth of denitrifying-related bacteria. This study was aimed at providing a scientific basis and parameters for TBDs used in engineering applications.
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    Screening of heterotrophic nitrification-aerobic denitrifying bacteria and its nitrogen removal characteristics
    ZHANG Ting-yue, DING Yu, HUANG Min-sheng
    Journal of East China Normal University(Natural Sc    2018, 2018 (6): 22-31,87.   DOI: 10.3969/j.issn.1000-5641.2018.06.003
    Abstract626)   HTML18)    PDF (1031KB)(566)      
    In order to find a high-efficiency denitrification method, a Pseudomonas genus-based strain was selected from the sediment of Cascade Pond in Longhong Ravine. The strain had heterotrophic nitrification and aerobic denitrification capability and was named LHJ-1. The results showed that the bacterial consortium LHJ-1 had clear heterotrophic nitrification capability; the utilization rates of NH4+-N and TOC were 99.90% and 56.69%, respectively. Concurrently, it demonstrated good denitrification ability, with conversion rates of NO3--N and NO2--N at 92.46% and 89.67%, respectively. Experiments evaluating environmental effects showed that various factors (e.g., C/N ratio, carbon source, pH, and DO concentration) could have a significant influence on the denitrification effect. Accordingly, different environmental factors should be investigated in practical applications to determine the optimum growth conditions for the best nitrogen removal efficiency. The screening of heterotrophic nitrification and aerobic denitrifying bacteria consortium LHJ-1 has broad application prospects for both denitrification and decarbonization of water.
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    Development history of sponge cities and the state of research on runoff pollution control
    YANG Yin-chuan, XIAO Bing, CUI He, HUANG Min-sheng, ZOU Ying, HE Yan, CAO Cheng-jin
    Journal of East China Normal University(Natural Sc    2018, 2018 (6): 32-42.   DOI: 10.3969/j.issn.1000-5641.2018.06.004
    Abstract491)   HTML25)    PDF (1089KB)(495)      
    Based on the development history of sponge city construction system in China and abroad, this paper explores the similarities and differences and development experiences of sponge cities in various countries. Taking the rain garden as the research object, this paper analyzes the effect of its structural composition, hydraulic characteristics, and plant configuration on runoff pollution; these can be used to provide a theoretical reference for the construction of sponge cities in China. Finally, potential problems and risks in the construction of the sponge city were presented, and suggestions and prospects for the construction of a sponge city such as mosquito breeding and plugging are presented, and suggestions and prospects for the construction of a sponge city in China are proposed. It is important to learn from the development history of foreign stormwater management systems and realize the "Sinification" of stormwater management in practice by:adapting to local conditions, focusing on regional differences, strengthening field trials, and exploring the control mechanism of sponge cities on runoff pollution. Meanwhile, the potential risks and problems related to plugging and mosquito breeding in sponge city construction should also be taken seriously.
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    Analysis of the pollutant emission reduction effect of a typical sponge project
    YANG Yin-chuan, XIAO Bin, CUI He, HUANG Min-sheng, YIN Chao, HE Yan, CAO Cheng-jin
    Journal of East China Normal University(Natural Sc    2018, 2018 (6): 43-49,112.   DOI: 10.3969/j.issn.1000-5641.2018.06.005
    Abstract395)   HTML10)    PDF (1225KB)(486)      
    Using a typical sponge city initiative (rain garden and grassed swale) in Chizhou, one of the earliest and largest sponge projects in China, as the research object, we tracked and monitored manholes in two residential areas one where the sponge project was implemented and one without transformation. Effluent quality of runoff rainwater was monitored to investigate the emission reduction effect of pollutants from the sponge project on runoff in residential areas. The results showed that the concentration of effluent pollutants in residential areas after renovation was significantly lower than that in unmodified rural areas. Rain gardens had lower concentrations of effluent than those in grassed swale, and the water quality of rainwater gardens was more stable. Finally, the economic and technical indicators of rain garden and grassed swale were analyzed.
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    Performance and factors of phosphorus interception in storing multi-pond wetlands in the Erhai Lake Basin
    LI Dan, HUANG Min-sheng, ZHENG Bing-hui, CHU Zhao-sheng
    Journal of East China Normal University(Natural Sc    2018, 2018 (6): 50-58,121.   DOI: 10.3969/j.issn.1000-5641.2018.06.006
    Abstract377)   HTML9)    PDF (1232KB)(399)      
    To investigate the characteristics and factors of phosphorus interception, phosphorus concentration from 12 storing multi-pond wetlands were analyzed. Evaluation of the removal efficiency and identification of the key factors of phosphorus removal were executed in the Erhai Lake Basin. The results showed that the water quality was effectively improved because phosphorus pollutants from the surface source pollution were intercepted in the storing multi-pond wetlands. The average interception efficiency value of η(PO43--P), η(TP) and η(SS) were 43.44%~93.88%、27.71%~89.67% and 21.84%~62.12%, respectively. Both the phosphorus concentration of the influent and the efficiency of phosphorus interception in the dry season were higher, respectively, than those in the wet season. Intermittent outflow of effluent provided a residence time which was long enough for the removal of pollutants in the dry season. While ρo(TP) had a significantly positive correlation with ρi(PO43--P) (R=0.297) and ρi(TP) (R=0.304). η(TP) showed a significant positive correlation with ρi(PO43--P) (R=0.665) and ρi(TP) (R=0.740). The efficiency of phosphorus removal primarily depended on the proportion of phosphate and the TP concentration of the influent. This study may provide support as an engineering case of multi-pond wetlands for the reduction of phosphorus into lakes, water pollution control in basins, and water restoration.
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    Enhanced denitrification for rural domestic sewage by a vertical flow constructed wetland
    CUI He, LU Xin-yu, CHANG Yue-ya, HUANG Min-sheng, LI Dan, HE Yan, CAO Cheng-jin
    Journal of East China Normal University(Natural Sc    2018, 2018 (6): 59-67.   DOI: 10.3969/j.issn.1000-5641.2018.06.007
    Abstract469)   HTML9)    PDF (1698KB)(451)      
    Two pilot-scale vertical flow artificial wetlands with "ceramic" as a single filler and "ceramic+zeolite" as composite fillers were studied, and their respective denitrification performance for rural domestic sewage was evaluated. To understand the denitrification mechanism of the two wetlands, the contribution rate of nitrogen removal by plant absorption and the diversity of the microbial community were analyzed. The object of this study was to provide a theoretical basis for the application of this wetland design to enhance denitrification at rural domestic sewage treatment plants. The results show that the mean removal rate of NH4+-N and TN by the vertical flow artificial wetland with "ceramic+zeolite" as composite fillers was 23% and 25% higher, respectively, than that of "ceramic" as single filler; the NH4+-N and TN concentration of the "ceramic+zeolite" wetland both attained Grade 1-B (GB 18918-2002). The contribution rate of plant absorption for nitrogen removal in the two wetlands was both less than 0.5%. Hence, nitrogen removal was primarily dependent on adsorption by the filler materialss and purification by microorganisms. The biofilm of plant roots and fillers in the wetland with "ceramic+zeolite" composite filler had better microbial community diversity. The concentration of bacteria with nitrogen removal capability (nitrification and denitrification) in the two vertical flow constructed wetlands were substantial, enabling enhanced denitrification of rural domestic sewage.
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    A review of the effects of endogenous sulfur on anaerobic ammonium oxidation in urban rivers
    HE Yan, CHEN Jing-han, HUANG Min-sheng, XU Yi-wen
    Journal of East China Normal University(Natural Sc    2018, 2018 (6): 68-73,130.   DOI: 10.3969/j.issn.1000-5641.2018.06.008
    Abstract419)   HTML9)    PDF (977KB)(381)      
    This paper reviews the state of current research on endogenous sulfur intervening in anaerobic ammonium oxidation as well as possible coupled microbial processes. Future research should focus on the role of new-type autotrophic anaerobic ammonium oxidation in nitrogen-cycling processes in urban rivers, including sulfur-driven autotrophic partial denitrification with anaerobic ammonium oxidation, sulfate-type anaerobic ammonium oxidation, and ferric iron reduction coupled with anaerobic ammonium oxidation; in addition, future research should explore the role of endogenous sulfur in intervening in anaerobic ammonium oxidation and their coupled progress in treating urban rivers with a high level of nitrogen and a low C/N ratio. This is of great significance for solving the issue of high nitrogen levels in treating polluted urban rivers as well as improving our understanding of microbial processes of N-and S-cycling in aquatic environments.
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    A review of the effect of endogenous sulfur on the environmental behavior of phosphorus in sediment from polluted rivers and lakes
    XU Yi-wen, HAN Jing, HE Yan, HUANG Min-sheng
    Journal of East China Normal University(Natural Sc    2018, 2018 (6): 74-80.   DOI: 10.3969/j.issn.1000-5641.2018.06.009
    Abstract390)   HTML8)    PDF (1027KB)(428)      
    Sulfur and phosphorus are important elements in the geochemical cycle. Both their environmental behavior and their coupled relationship are intertwined to regulate the release of endogenous pollution from sediment in polluted rivers and lakes. This paper summarizes the environmental behavior of sulfur and phosphorous as well as the latest research progress on their coupling mechanisms. The study also notes that sulfur-driven eutrophication is an important type of water eutrophication in polluted rivers and lakes. Lastly, we discuss future perspectives on related research in terms of coupled S-cycling with other biogeochemical cycles, which can provide referential significance for the treatment of endogenous pollution in polluted rivers and lakes.
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    Biodegration of LAS in an urban malodorous river
    YIN Chao, HUANG Min-sheng, HE Yan, CUI He, WANG Di-fang, ZHANG Ting-yue, XIAO Bing
    Journal of East China Normal University(Natural Sc    2018, 2018 (6): 81-87.   DOI: 10.3969/j.issn.1000-5641.2018.06.010
    Abstract413)   HTML11)    PDF (943KB)(301)      
    Biodegradation of the anion-surfactant LAS in the urban malodorous water of Liwan River in Putuo District (Shanghai) was studied by "river-die away"under different conditions. In particular, the influences of temperature, pH, initial concentration of LAS, nutrients (C6H12O6) and aeration conditions on the biodegradation of LAS were investigated. The study showed that when the temperature increased from 10℃ to 30℃, the half-life of LAS decreased from 6.5 days to 2.5 days. The biodegration of surfactant at pH=8.5±0.2 was slightly better than that at pH=7.5±0.2 and pH=9.5±0.2. With greater initial concentration, the half-life of LAS increased from 2.9 days to 3.4 days. C6H12O6 inhibited degradation of LAS, but the degradation of LAS accelerated under continuous aeration conditions.
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    Coupling of endogenous sulfur and iron with nitrogen behavior in a heavily polluted tidal river
    GUAN Hui-min, ZHU Jin, HE Yan, HUANG Min-sheng, ZHOU Kun, ZHU Lin-lin
    Journal of East China Normal University(Natural Sc    2018, 2018 (6): 88-96.   DOI: 10.3969/j.issn.1000-5641.2018.06.011
    Abstract394)   HTML8)    PDF (1724KB)(364)      
    To study the impact of tidal effects on endogenous sulfur(S), iron (Fe), and nitrogen (N), as well as their possible coupling, the present work investigated the dynamic variations of endogenous S, Fe and N using a simulated heavily polluted tidal river system. In addition, Grey relational analysis (GRA) was applied to elucidate the coupling of endogenous S, Fe and N behavior. The results showed a NH4+-N reduction rate of (82.2±1.92)% and a TN reduction rate of (86.49±2.31)% for the simulated tidal system. The simulation suggested that a tidal alternation facilitated the formation of an oxic-anoxic-anaerobic microenvironment at the sediment-overlying water interface and thus stimulated the coupled nitrification-denitrification process, which was in favor of ammonium and total nitrogen removal. Grey relational analysis (GRA) showed the highest integrated grey relational grade between nitrate and reduced sulfur (0.910 5) and nitrate and iron (0.858 7) in interstitial water. The results indicated that nitrate was most affected by reduced sulfur and iron; we postulate that endogenous sulfur and iron with nitrogen might exist by sulfur-driven autotrophic denitrification or iron-driven autotrophic denitrification. This study may provide reference for treatment and restoration of heavily polluted tidal rivers.
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    Analysis of microbial community composition from media used to strengthen total nitrogen removal from an urban river
    HAN Jing, XU Yi-wen, HE Yan, HUANG Min-sheng
    Journal of East China Normal University(Natural Sc    2018, 2018 (6): 97-104.   DOI: 10.3969/j.issn.1000-5641.2018.06.012
    Abstract373)   HTML10)    PDF (2911KB)(352)      
    We compared the removal rate of total nitrogen in urban rivers with three kinds of media (biochar, felt, and non-woven fabric). After 84 days in operation, it was found that non-woven fabric increased the removal rate of total nitrogen by 23.4% over the control group; felt increased the removal rate of total nitrogen by 13.9% over the control group; and biochar had a poor effect on total nitrogen removal. The microbial diversity and community composition of different media-enhanced groups were then systematically explored; the results showed that non-woven fabric can significantly increase microbial diversity and abundance. Moreover, proteobacteria, which is related to nitrogen conversion, was found to be significantly higher in the non-woven fabric group than the felt and biochar groups, especially the abundance of denitrifying bacteria (Azospirillum, Thiobacillus, and Azoarcus). The abundance of methanogen, which is in competition with the denitrifying bacteria Syntrophorhabdus, was found to be lower in non-woven fabric than in the control and biochar groups. The microbial flora structure of the felt group showed a similar trend to that of the non-woven fabric group, but the abundance of denitrifying bacteria was lower. The microbial community composition of the biochar group was the most similar to that of the control group. It is speculated that non-woven fabric has better biocompatibility than other groups; this is beneficial for biofilm formation and thereby promotes the growth of denitrifying bacteria. In a comprehensive comparison, non-woven media materials are more conducive to the removal of total nitrogen in urban rivers.
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    Larvae breeding conditions of “sponge” in a sponge city and its mechanic analysis: A case study of Chizhou in Anhui Province
    XIAO Bing, YANG Yin-chuan, LU Xin-yu, LI Xin-ran, HUANG Min-sheng, YIN Chao, HE Yan
    Journal of East China Normal University(Natural Sc    2018, 2018 (6): 105-112.   DOI: 10.3969/j.issn.1000-5641.2018.06.013
    Abstract415)   HTML11)    PDF (1275KB)(370)      
    The goal of a sponge city is to solve the water problems faced by a city. However, there may exist risks of larvae breeding owing to the stagnant water in sponges. In order to study the status of larvae breeding and its factors in sponges, as a basis for mosquito prevention and control, this study monitored stagnant water, water quality, and mosquito larvae of typical sponges in Chizhou from March to August of 2017. The results showed that larvae bred in Rain Pond 1 of Chizhou No.1 Middle School because of poor water quality (below Class V), extended duration of water retention (2——3 months), adequate blood meal, and the lack of predators; however, larvae were not found in the rest of the sponges. The monthly larvae densities from June to August of 2017 were 1.6, 2.2 and 1.0 per dip, respectively, with 100%, 50%, and 20% dip index, requiring related control management. Accordingly, this risk should be considered in the planning, design, and maintenance stages of a sponge.
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    Mosquito breeding conditions and analysis of mechanisms of the urban water-green combined system: A case study on the riparian zone of Changfeng Park and the drainage system of Shanghai's west outer-ring greenbelt
    XIAO Bing, LU Xin-yu, HUANG Min-sheng, LI Xin-ran, YIN Chao, HE Yan
    Journal of East China Normal University(Natural Sc    2018, 2018 (6): 113-121.   DOI: 10.3969/j.issn.1000-5641.2018.06.014
    Abstract388)   HTML12)    PDF (4842KB)(354)      
    This paper studied two kinds of urban water-green combined systems, where mosquito larvae were found, hoping to provide a theoretical basis for urban mosquito control and prevention through the comparison and analysis of different factors. The results showed that the larval density in the outer-ring greenbelt drainage system, whose water quality was below Class V, was significantly higher than the larval density in the riparian zone of Changfeng Park with Class IV water (p<0.05); this can be attributed to the relatively poorer water quality and plant cover, fewer predators, weaker illumination, and so on. The larval density reached 157.6 per dip in peak season in the west outer-ring greenbelt drainage system. Because of the relative closure and overcrowded vegetation, mosquito larvae in the Calamus Pit only appeared in late spring and early summer, but with high density. The larval density was low in Lotus Pond owing to the open water surface and the connection with Yinchu Lake. The rock-filled revetment of Tiebi Hill provides shelters for larval survival. Both areas had a risk for mosquito-borne diseases, requiring relevant measures such as filling, revetment restructuration, and environmental improvement. The overwintering form of Culex pipiens pallens are adults and the time difference of the larval presence can be attributed to the availability of blood meal. The larval density was negatively correlated to DO and chlorophyll-a concentration, but positively correlated to NH4+-N, TP, BOD5, and CODMn.
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    Analysis of water quality and mosquito larval breeding at the tail water wetland of the Shanghai East Water Purification Plant
    LU Xin-yu, XIAO Bing, HUANG Min-sheng, HE Yan, LI Xin-ran, YIN Chao, LENG Pei-en
    Journal of East China Normal University(Natural Sc    2018, 2018 (6): 122-130.   DOI: 10.3969/j.issn.1000-5641.2018.06.015
    Abstract421)   HTML13)    PDF (2199KB)(356)      
    In this study, a constructed wetland for advanced treatment of tail water at the Shanghai East Water Purification Plant was taken as an example to explore the relationship between environmental factors, such as water quality and mosquito (Culex pipiens pallens) larval breeding. The comprehensive pollution index (P Value) method and organic pollution index (A Value) method were used to evaluate the water quality of wetland from May to November of 2017. The breeding status of mosquito larvae at 14 sample points in the wetland were monitored by the standard dipping method during this period. The subsequent analysis showed that:① The water quality of the wetland was better than Class V of the environmental quality standard for surface water; ② The larval density was higher in water whose P Value was equal to or greater than 143.1 per spoon; ③ The larval density was high between May and August and declined with the decrease of temperature; ④ The larval density was significantly lower in areas where the water surface could be exposed to direct sunlight (p<0.05); and ⑤ The larval density was small when the concentration of Chlorophyll a was high, and excessive duckweed coverage can inhibit mosquito breeding.
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