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The Chinese experience at the International Mathematical Olympiad Bin XIONG, Peijie JIANG Journal of East China Normal University(Natural Science)    2021, 2021 (6): 1-14.   DOI: 10.3969/j.issn.1000-5641.2021.06.001 Abstract （2771）   HTML （771）    PDF（pc） （1371KB）（13522）       Knowledge map    Save The International Mathematical Olympiad (IMO) is one of the most important and influential global youth intellectual competitions. However, there is little research on how to effectively organize the competition at the national level to help cultivate talent in mathematics, science, and technology. The Mathematical Olympiad originated from a competition to solve mathematical problems. Many outstanding mathematicians and scientists have been prior winners of the IMO and have reaped benefits subsequently to some extent. The Mathematical Olympiad helps to select and train gifted students in mathematics. China’s outstanding historical achievements in the IMO have attracted the attention of the world. Many of China’s students, who exhibited exceptional performance at the IMO, later became outstanding mathematicians, scientists, and technologists. These achievements need to be publicized, and the Chinese experience at the Mathematical Olympiad needs to be summarized and promoted. This article summarizes the history of the IMO and reviews the practices of the IMO in China based on the literature. China uses a number of strategies to ensure outstanding results in the IMO, including: the selection of contestants from existing domestic programs (National High School Mathematics Joint Competition, Chinese Mathematical Olympiad, and National Training Team); a multi-level educational system based on school training; and the accumulation and publication of relevant learning materials. The outbreak of the novel coronavirus has affected the normal proceedings of the IMO, but China has implemented effective countermeasures. There are still some misunderstandings about the Mathematical Olympiad in China. By introducing prior contestants, who have participated in the IMO and made outstanding contributions, China can help the public better appreciate the Mathematical Olympiad. At the same time, the Chinese experience at the IMO is an important reference for other countries in organizing competition training and selecting and nurturing gifted students in mathematics. Table and Figures | Reference | Related Articles | Metrics | Comments（0）

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Advances in research on multimedia fate, risks, and simulation of contaminants of emerging concern in urban agglomerations Chenming GU, Jing YANG, Ye LI, Ye HUANG, Yan WU, Guoyu YIN, Ruihe JIN, Yi YANG, Min LIU Journal of East China Normal University(Natural Science)    2024, 2024 (6): 24-38.   DOI: 10.3969/j.issn.1000-5641.2024.06.003 Abstract （1389）   HTML （60）    PDF（pc） （1726KB）（11847）       Knowledge map    Save The high degree of integration between cities has made urban agglomerations one of the key carriers of global economic development. However, the rapid economic growth; industrial restructuring; and subsequent adoption of new technologies, materials, and products, coupled with high-intensity human activities in urban agglomerations, have led to increasingly serious issues of environmental emissions and the accumulation of contaminants of emerging concern (CECs). The complexity, diversity, migration, transformation, accumulation, and ecological risks of CECs in surface environments have made them a central scientific issue in surface environmental process research. This article systematically elaborates on the spatiotemporal differentiation characteristics and migration mechanisms of CECs in urban agglomerations across multimedia, summarizes research progress on the source emissions and contributions of CECs in urban agglomerations at home and abroad, reviews the models of multimedia fate of CECs in urban agglomerations and the methods for ecological health risk assessment, discusses the shortcomings of research on CEC contamination in urban agglomerations, and proposes key scientific issues that need to be addressed in future research. Reference | Related Articles | Metrics | Comments（0）

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Techniques for estimating click-through rates of Web advertisements: A survey JI Wen-di, WANG Xiao-ling, ZHOU Ao-ying Journal of East China Normal University(Natural Sc    2013, 2013 (3): 1-14.   Abstract （6966）      PDF（pc） （1639KB）（8399）       Knowledge map    Save Computational advertising is a kind of advertising mechanism which has the capability to find the most suitable ads for given users and web content, so as to advertises them accurately. Therefore, estimating click-through rate (CTR) precisely makes significant difference in the efficiency of advertising on the Internet. Ad click-through rate prediction is to estimate CTR with click log, which is influenced by the nature features of ad, the position, the page information, user properties, the reputation of advertisers and such other factors. This paper is aimed to illustrate useful CTR prediction models, including CTR models for ads of abundant history data, CTR models for rare ads or new ads and some optimization models. Finally, the implementation methods with real data set were demonstrated as examples. Reference | Related Articles | Metrics | Comments（0）

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Click-through rate prediction of online advertisements based on probabilistic graphical model YUE Kun, WANG Chao-lu, ZHU Yun-lei, WU Hao, LIU Wei-yi Journal of East China Normal University(Natural Sc    2013, 2013 (3): 15-25.   Abstract （6395）      PDF（pc） （1294KB）（7468）       Knowledge map    Save CTR (Click-Through Rate) prediction can be used to improve users’ satisfaction with respect to the presented online advertisements (ads) and support effective advertising. CTR prediction is the basis for personalized recommendation of online ads. It is also necessary to re-commend ads and predict their CTRs for the users that have no historical click-through records. In this paper, we adopted BN (Bayesian network), an important probabilistic graphical model, as the framework for representing and inferring the similarity and the corresponding uncertainty of the behaviors in ad search of different users. First, we constructed the BN to reflect the similarity between users by means of statistic computations on the historical records of user’s ad search. Then, we measured the behavior similarity between the users with click-through records and those without records quantitatively based on the mechanism of BN’s probabilistic inferences. Consequently, we predicted the CTRs of ads with respect to the users without historical click-through records, in order to provide a metric for ad recommendation. We made experiments on the training data of Tencent CA from KDD Cup 2012-Track 2 and tested the effectiveness of our methods. Reference | Related Articles | Metrics | Comments（0）

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Ant colony optimization algorithm for computing resource allocation based on cloud computing environment (Chinese) HUA Xia-yu;ZHENG Jun;HU Wen-xin Journal of East China Normal University(Natural Sc    2010, 2010 (1): 127-134.   Abstract （5583）      PDF（pc） （1353KB）（7230）       Knowledge map    Save A new allocation algorithm based on Ant Colony Optimization (ACO) was established to satisfy the property of cloud computing. When start, this algorithm first prognosticated the capability of the potential available resource nodes, then analyzed some factors such as network qualities or response times to acquire a set of optimal compute resources. This algorithm met the needs of cloud computing more than others for grid environment with shorter response time and better performance, which were proved by the simulation results in the Gridsim environment. Related Articles | Metrics | Comments（0）

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Research status and development studies of motion sensing technology ZHANG Shi-chao, QIAN Dong-ming Journal of East China Normal University(Natural Sc    2014, 2014 (2): 40-49, 126.   Abstract （3115）      PDF（pc） （1021KB）（6816）       Knowledge map    Save This thesis introduced the basic concepts and development of the human-computer interaction technology, as well as its applications in education and related areas. On this basis, Kinect would be used as a case study, including its application in the data of the depth, and skeleton tracking. Reference | Related Articles | Metrics | Comments（0）

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Online advertising systems and related technology evolution SONG Le-yi, GONG Xue-qing, ZHANG Rong, LIU Peng Journal of East China Normal University(Natural Sc    2013, 2013 (3): 106-117.   Abstract （5249）      PDF（pc） （1590KB）（6799）       Knowledge map    Save This paper introduced the background and related techniques of online advertising market. While different types of online ads may imply different computational advertising techniques in the backend system, this paper provided a rational classification method of online advertising formats. The category of online advertising given in this paper covers existing and potential types in the domain. Further, the advertising platform have evolved in several major phases or generations, particularly ad server, ad network and ad exchange. We showed the system architectures of the advertising systems mentioned above, by discussing the main function modules and interfaces. Our work aims to give a comprehensive and detailed description of the online advertising systems from the view of computation. Besides, the surveys in our work can provide essential background knowledge for computational advertising related research. Reference | Related Articles | Metrics | Comments（0）

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Advancements in bio-tracking and bio-imaging technologies for microplastics Cuizhu MA, Wenjun ZHAO, Yufei CHEN, Huahong SHI Journal of East China Normal University(Natural Science)    2024, 2024 (6): 14-23.   DOI: 10.3969/j.issn.1000-5641.2024.06.002 Abstract （1392）   HTML （69）    PDF（pc） （885KB）（6573）       Knowledge map    Save This article reviews the advancements in bio-tracking and imaging techniques for microplastics (MPs). Currently, fluorescent labeling, metal labeling, and isotope labeling are commonly employed, with fluorescent tracers being the most widely used method. Hyperspectral imaging, surface-enhanced Raman imaging, and polarized light imaging are also used due to the spectral characteristics of plastics. Combined with high-resolution imaging technology, tissue clearing made it possible to visualize three-dimensional (3D) imaging, providing a new perspective for in-depth research on the biological effects of MPs. Using various tracking technologies and imaging methods combined with 3D processing and analysis software will elucidate the distribution of microplastics in different organs and even individual organisms in the future. This comprehensive analysis method is expected to provide a stronger scientific foundation for the environmental risk assessment and management of MPs. Table and Figures | Reference | Related Articles | Metrics | Comments（0）

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Structure-conductive property relationship of polypyrrole YU Bo, XU Xue-cheng Journal of East China Normal University(Natural Sc    2014, 2014 (4): 77-87.   Abstract （3437）      PDF（pc） （1700KB）（6293）       Knowledge map    Save Polypyrrole was synthesized by oxidative chemical polymerization. Samples presenting different conductivities were obtained by adjusting the preparing temperature. The polypyrrole samples have been investigated by means of four probe method, Solid state 13C NMR spectrum, XRD, FTIR spectroscopy, Raman spectrum and XPS, respectively. The experimental result suggested the fact that the conductivity of polypyrrole samples gradually decreases as the preparation temperature increases. The analysis indicates it is because the changing of internal structure follows the varying of external preparation conditions. The commonly structure of polypyrrole is a linear chain of monomers bonded by α-α carbons at a low preparation temperature. Through such a structure polypyrrole can form both a relatively planar configuration and a relatively planar conformation. This sort of structure provides the sample with a preferable regularity, a longer conjugated chain length and a higher conductivity. However, the ratio of α-α linkage drops as the preparation temperature increases, by which the structure of molecular is damaged, the degree of order declines. The carrier mobility of polypyrrole, as well as the conductive property, became lower. Reference | Related Articles | Metrics | Comments（0）

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Survey of online advertising target GUO Xin-yu， LIU Peng， ZHOU Min-qi， ZHOU Ao-ying Journal of East China Normal University(Natural Sc    2013, 2013 (3): 93-105.   Abstract （3884）      PDF（pc） （1139KB）（6276）       Knowledge map    Save Online advertising has sprung up and shown its diversity for decades. With the rapid increase of online advertising markets,a growing numbers of advertisers want to deliver ads related to their products or services to specific users with less expenditure. They expect these users have great interest in their products or services and have good intersection with ads(users see the ads, click it, registration or buy the products). Thus the concept of “advertising target” is proposed. This chapter discusses several classification of advertising target and for each category we elaborate on its application scenarios. We then summary and contrast the important advertising target methods and models used in recent years. Reference | Related Articles | Metrics | Comments（0）

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Research of large scale graph data management with in memory computing techniques YUAN Pei-Sen, SHU Xin, SHA Chao-Feng, XU Huan-Liang Journal of East China Normal University(Natural Sc    2014, 2014 (5): 55-71.   DOI: 10.3969/j.issn.10005641.2014.05.005 Abstract （2587）      PDF（pc） （2216KB）（6076）       Knowledge map    Save Graph is an important data model, which can describe structural information including dependent relationship, such as transportation network, social network and webpage hyperlink. Management of big graph brings challenges for traditional techniques, however, distributed cluster provide platform and techniques for this problem. Nowadays, the ratio of performance and price of memory promote rapidly, while demand of applications of highperformance, inmemory computing for massive data management is becoming popular. The storage and evaluation of massive graph requires highperformance platform. In this context, it’s significant for studying graph data management with inmemory techniques. This paper surveyes key techniques of management of massive graph data, and researched graph data management of inmemory computing techniques，and finally summarizes the paper. Related Articles | Metrics | Comments（0）

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Analysis of tidal characteristics of the tide gauges in the Changjiang Estuary YANG Zheng-dong, ZHU Jian-rong, WANG Biao, LIN Tang-yu Journal of East China Normal University(Natural Sc    2012, 2012 (3): 111-119.   Abstract （8071）      PDF（pc） （1190KB）（6047）       Knowledge map    Save Based on the measured water levels at Hengsha, Majiagang, Baozhen and Yonglongsha tide gauges in 2009, the tidal temporal and spatial variations, tidal constituents, tidal form and distortion at these gauges in the Changjiang Estuary were analyzed. There exist tidal daily inequalities that mainly occur during high tide levels, and are more significant during neap tides than spring tides in March and September while are more significant during spring tides than neap tides in June and December. The monthly maximum and minimum tidal ranges in each month at the tide gauges were given out statistically. The tidal range in the estuary varies monthly with two peaks: the maximum tidal range reaches the maximum values in March and September, and reaches the minimum values in June and December. The minimum tidal range reaches the maximum values in June and December, and reaches the minimum values in March and September. The tidal range in the South Branch reduced toward upstream due to the river discharge and friction. The tidal range at Yonglongsha tidal gauge is the largest among the 4 tidal gauges because the North Branch has small river discharge division ratio and funnel shape bathymetry. The tide is mainly composed by the 4 semi-diurnal tidal constituent (M 2、S 2、N 2、K 2), 4 diurnal tidal constituent (K 1、O 1、P 1、Q 1) and 3 shallow water tidal constituent (M 4、MS 4、M 6). The semi-diurnal tidal constituents M 2 and S 2 are the predominant ones, and the shallow water tidal constituents M 4 and MS 4 are apparent due to the shallow water in the estuary. The tidal form number in the South Branch is larger than 0.25, indicating where the tide is an irregular semi-diurnal tide type there, and is smaller than 0.25 in the North Branch, indicating where the tide is a regular semi-diurnal tide type. The tidal distortion coefficients in the 4 tidal gauges are all larger than 0.1, indicating that the tide at the tide gauges has significant distortion in the Changjiang Estuary, especially at Yonglongsha in the North Branch with tidal distortion coefficient 0.173. Reference | Related Articles | Metrics | Comments（0）

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Survey of resource uniform management and scheduling in cluster LI Yong-Feng, ZHOU Min-Qi, HU Hua-Liang Journal of East China Normal University(Natural Sc    2014, 2014 (5): 17-30.   DOI: 10.3969/j.issn.10005641.2014.05.002 Abstract （2612）      PDF（pc） （1403KB）（5980）       Knowledge map    Save With the rapid development of Internet and the coming of big data, resource management system, a thin resource sharing layer that enables sharing cluster across diverse cluster computing frameworks, by giving frameworks a common interface for accessing cluster resources. For powering both large Internet services and a growing number of dataintensive scientific applications, cluster computing framework will continue emerge, and no framework will be optimal for all applications. Therefore, multiplexing a cluster between frameworks makes significant difference. Deploying and running multiple frameworks in the same cluster, improves utilization and allowing applications to share access to large datasets that may be costly to replicate across clusters. This paper is aimed to illustrate current major techniques of resource management and scheduling in cluster, including resource representation model, resource allocation model and scheduling policy. Finally, current prominent solutions, which have been developed and used by many companies, will be demonstrated, and we then summary and contrast these solutions used in recent years. Related Articles | Metrics | Comments（0）

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Development of parallel computing models in the big data era PAN Wei, LI Zhan-Huai Journal of East China Normal University(Natural Sc    2014, 2014 (5): 43-54.   DOI: 10.3969/j.issn.10005641.2014.05.004 Abstract （2538）      PDF（pc） （459KB）（5979）       Knowledge map    Save In the era of big data, the changing of the constraints gives the parallel computing opportunities and challenges for developing. This paper reviewed the new progress and changes of the parallel computing; combining with the effects of the hardware environments, computing pattern, application requirements on the parallel computing, the relevant research on batchoriented parallel computing model, streamingoriented parallel computing model, graphoriented parallel computing model and inmemory parallel computing model are summarized; Finally, the future development trends are evaluated. Related Articles | Metrics | Comments（0）

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JIANG Dong-Xing, FU Xiao-Long, YUAN Fang, WU Hai-Yan, LIU Qi-Xin Journal of East China Normal University(Natural Sc    2015, 2015 (S1): 119-125.   DOI: 10.3969/j.issn.1000-5641.2015.z1.020 Abstract （2310）      PDF（pc） （984KB）（5856）       Knowledge map    Save Related Articles | Metrics | Comments（0）

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Study on the mechanism of methylene blue degradation by TiO2 photocatalyst ZHANG Dan, XU Bin, ZHU Pei-juan, LIAN Zheng-hao, ZHAO Ya-ping Journal of East China Normal University(Natural Sc    2013, 2013 (5): 35-42.   Abstract （5181）      PDF（pc） （2193KB）（5812）       Knowledge map    Save In order to carry out the study, the experiments of photodegradation of methylene blue under different conditions were conducted, using different kinds of free radical scavengers, such as (CH3)3OH, H2O2, KI, NaN3 and C6H4O2. The effects of these free radical scavengers were observed. The concentration of H2O2 generated during the photodegradation of methylene blue by TiO2 was also reported. And the results of these experiments indicated that the main active oxygen substances in the reaction are ·OH, O·-2 and 1O2. Reference | Related Articles | Metrics | Comments（0）

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Simulator for hybrid memory architecture LIU Dong, ZHANG Jin-Bao, LIAO Xiao-Fei, JIN Hai Journal of East China Normal University(Natural Sc    2014, 2014 (5): 133-140.   DOI: 10.3969/j.issn.10005641.2014.05.011 Abstract （3042）      PDF（pc） （1508KB）（5686）       Knowledge map    Save This paper proposed a method for building a simulator for hybrid memory architecture based on gem5. When building, this method first added a hybrid memory controller between the memory bus and the memory model, then introduced the nonvolatile memory model of NVMain and hooked it up to the the newly added hybrid memory controller along with the native DRAM model of gem5. This method could achieve the goal of building a simulator for hybrid memory architecture, which was proved by the experiment results. Related Articles | Metrics | Comments（0）

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Young type inequalities for matrices HU Xing-kai Journal of East China Normal University(Natural Sc    2012, 2012 (4): 12-17.   Abstract （3937）      PDF（pc） （144KB）（5681）       Knowledge map    Save First, some Young type inequalities for scalars were given. Then on the base of them, corresponding Young type inequalities for matrices were established. Reference | Related Articles | Metrics | Comments（0）

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Research on the framework of specification for e-Textbook and e-Schoolbag WU Yong-he， ZHU Zhi-ting， HE Chao Journal of East China Normal University(Natural Sc    2012, 2012 (2): 70-80.   Abstract （6056）      PDF（pc） （2795KB）（5661）       Knowledge map    Save With the development of information technology, the e-Textbook and e-Schoolbag is received more concerns from the community, its promotion and popularization is becoming the trend. First, this paper analyzes the demand of e-Textbook and e-Schoolbag from perspective of research on framework of standards. Then it describes the framework of e-Textbook and e-Schoolbag, including conceptual model, system framework model, hierarchy diagram for e-Textbook and e-Schoolbag system and function model. At last, it gives architecture of standards for e-Textbook and e-Schoolbag and profiles of related standards for e-Textbook and e-schoolbag. Reference | Related Articles | Metrics | Comments（0）

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Study of electronic structures and the micro-solvation effect of SO3– and HSO3– in atmospheric aerosols Jianan CHEN, Zhipeng LI, Yanrong JIANG, Zhubin HU, Haitao SUN, Zhenrong SUN Journal of East China Normal University(Natural Science)    2022, 2022 (1): 31-42.   DOI: 10.3969/j.issn.1000-5641.2022.01.005 Abstract （1150）   HTML （50）    PDF（pc） （942KB）（5403）       Knowledge map    Save In this study, we used negative ion photoelectron spectroscopy (NIPES) combined with quantum chemical calculation to explore the electronic structures, micro-solvation effect, and stabilization mechanism of two compounds, SO3– and HSO3–, that are readily abundant in the atmosphere. Vertical detachment energies of (3.31 ± 0.02) and (3.91 ± 0.02) eV and adiabatic detachment energies of (3.02 ± 0.05) and (3.56 ± 0.05) eV were measured for SO3– and HSO3–, respectively. These results are reproduceable when using a nuclear ensemble approach and Dyson orbitals in the calculation. The typical density of states method, however, cannot demonstrate the nuclear vibration effect, ionization probability, and orbital relaxation effect during the ionization process. We studied the micro-solvation effect of HSO3–·(H2O)n (n = 0 ~ 5) and found that system stability was enhanced by an increase in the surrounding water molecules, whereby electrostatic interaction played a dominant role and the induction effect made an increasingly important contribution. We believe this work will help improve the modeling of atmospheric sulfate aerosols and provide a scientific basis for the effective control of haze formation. Table and Figures | Reference | Related Articles | Metrics | Comments（0）