Photo News   
25 July 2025, Volume 2025 Issue 4 Previous Issue   
For Selected: Toggle Thumbnails
Online grant prediction for mobile networks based on traffic perception
Yufei FU, Zesong XU, Anhao FENG, Tongquan WEI
2025, 2025 (4):  1-14.  doi: 10.3969/j.issn.1000-5641.2025.04.001
Abstract ( 25 )   HTML ( 0 )   PDF (1468KB) ( 4 )  

In mobile networks, mobile devices need to continuously monitor the control channels to ensure that they receive all the grants for scheduling sent by the base station, which results in enormous energy waste when the base station does not send any grants. Predicting the pattern of grant sending can effectively reduce such waste. Existing approaches to grant prediction can achieve high accuracy in specific traffic scenarios, but it’s still difficult for them to cope with dynamically changing communication environments. To solve this problem, an online grant prediction method based on traffic scenario perception is proposed. Firstly, the method extracts features from historical grant information sequences and perform a clustering of these features to classify various traffic scenarios. Then, a single prediction model is designed and trained offline for each class of scenarios. During the online prediction stage, the system selects the most appropriate model for prediction based on the results of traffic scenario perception. Experimental results show that, the proposed method is able to reduce prediction error rate by up to 81.52% compared with the benchmarking methods and can achieve effective energy savings on both simulated and real traffic traces. In addition, the proposed approach to traffic scenario perception is able to significantly reduce the computational complexity compared with the benchmarking approach, which makes it more suitable for real-time traffic scenario perception.

Figures and Tables | References | Related Articles | Metrics
Parallax image mosaic based on matching points and thin plate splines function model optimization
Jiefang CHEN, Chang HUANG
2025, 2025 (4):  15-27.  doi: 10.3969/j.issn.1000-5641.2025.04.002
Abstract ( 28 )   HTML ( 5 )   PDF (7373KB) ( 0 )  

To solve the redundancy of matching points and local distortion of image after mosaic in intelligent driving, a parallax image mosaic algorithm based on optimization of matching points and improvement of thin plate spline function model is proposed. First, a sparse matrix is constructed according to the distribution positions of image matching points. Second, the number of mesh constrained matching points is used to eliminate redundant matching points, which reduces the time of calculating thin plate spline function model. Finally, an improved thin plate spline function model is used for image registration. The experimental results indicate that the proposed algorithm eliminates the redundancy of matching points and improves the image distortion problem, which has certain superiority and effectiveness.

Figures and Tables | References | Related Articles | Metrics
Container lock pins recognition based on a self-built dataset with high completeness
Xingxing XU, Chang HUANG
2025, 2025 (4):  28-37.  doi: 10.3969/j.issn.1000-5641.2025.04.003
Abstract ( 14 )   HTML ( 6 )   PDF (1320KB) ( 0 )  

The recognition accuracy of container lock pins is a main factor affecting the efficiency of automatic dismantling of terminals. However, the shape and structure of container lock pins are different, and traditional methods, such as hand-made descriptors for lock pin recognition, are slow and inaccurate. This study proposes a 3D point cloud recognition method for container locking pins based on self-built datasets with high completeness; additionally, a 3D point cloud dataset of container locking pins with high completeness is constructed by realizing a semi-automatic collection system for 3D point cloud data collection of many container locking pins. Based on the self-built dataset, a point cloud classification deep learning network algorithm is used to train the model to verify the rationality of the method of constructing the dataset and the effectiveness of the dataset. The results indicate that the lock-pin recognition method based on the self-built dataset with high completeness has high accuracy. Moreover, the recognition accuracy of a complete single-view 3D point cloud can reach 100%, it is not easily affected by external environmental factors, and it has good performance in the case of missing parts of the point cloud. The research results can provide theoretical and technical support for the automatic identification and disassembly of container lock pins in terminals.

Figures and Tables | References | Related Articles | Metrics
A high robust fast video steganography algorithm in lossy channels
Zheng HU, Chang HUANG
2025, 2025 (4):  38-48.  doi: 10.3969/j.issn.1000-5641.2025.04.004
Abstract ( 13 )   HTML ( 0 )   PDF (1438KB) ( 0 )  

High-definition videos lose hidden information when compressed by lossy channels during transmission. Concurrently, efficient video steganography algorithms require hardware implementation to achieve low-power, high-speed, and reliable real-time processing. To ensure real-time and reliable transmission of secret data, the steganography algorithm requires low complexity and high robustness. Therefore, this study proposes an efficient and robust steganography algorithm for hardware platform implementations. The algorithm employs the generation principle and distribution characteristics of DC (Direct Current) coefficients to modify the pixel values directly in the spatial domain rather than in the discrete cosine transform domain. Therefore, the proposed algorithm exhibits both the simplicity of the spatial-domain steganography algorithm and the high robustness of the transform-domain steganography algorithm. Experimental results show that the proposed algorithm has low computational complexity and exhibits excellent robustness and visual quality in local lossy channel compression.

Figures and Tables | References | Related Articles | Metrics
C-T Net: Remote sensing image change detection model integrating CNN and Transformer
Yi WU, Shilin YUN
2025, 2025 (4):  49-60.  doi: 10.3969/j.issn.1000-5641.2025.04.005
Abstract ( 26 )   HTML ( 1 )   PDF (4156KB) ( 4 )  

Due to factors such as differences in acquisition time, angle, and sensor characteristics, dual temporal remote sensing images often manifest various pseudo-changes. Moreover, certain changes may have an uninteresting nature and typically correlate with adjacent objects. However, the utilization of a fully convolutional neural network (FCN) may lead to the loss of long-range information. To address this issue, this study proposes a network that integrates convolutional neural networks (CNN) and Transformer (C-T Net), which has an overall network architecture consisting of a deep feature extraction section and a detection head section. The network backbone combines CNN and Swin Transformer. Additionally, two novel fusion modules, C-to-T and T-to-C, are designed to amalgamate local features and global features. The detection head section utilizes Transformer encoding and decoding to derive refined feature maps for discerning change regions. Comparative experiments with multiple change detection models validate the efficacy of C-T Net. On the LEVIR-CD and WHU-CD datasets, the proposed method achieves the highest F1_1 (90.63%, 86.24%) and $ {p}_{\mathrm{I}\mathrm{o}\mathrm{U}} \_1 $(82.87%, 75.81%). Results across both datasets affirm that our proposed algorithm outperforms existing methodologies from both visual and data-centric perspectives.

Figures and Tables | References | Related Articles | Metrics
Theoretical study on the formation mechanism of interstellar molecule 1-cyano-1,3-butadiene in a high-temperature interstellar environment
Yue YANG, Tao YANG, Zhihao JIN
2025, 2025 (4):  61-68.  doi: 10.3969/j.issn.1000-5641.2025.04.006
Abstract ( 14 )   HTML ( 0 )   PDF (960KB) ( 2 )  

The formation mechanism of interstellar molecule 1-cyano-1,3-butadiene (C5H5N) in high-temperature interstellar environments was explored via quantum chemical calculations. Using cyanomethyl radical (CH2CN) and propyne/allene (C3H4) as reaction starting materials, the corresponding reaction potential energy surface, reaction rate, and product branch ratio were calculated at the B3LYP/cc-pVTZ level, thus deepening the study of interstellar isomers. The initial step of the reaction is the barrier-free addition of cyanomethyl radicals to the terminal carbon atoms of propyne/allene, which primarily produces E-1-cyano-1,3-butadiene and Z-1-cyano-1,3-butadiene. The research represents a class of reactions involving cyano-substituted hydrocarbons and other unsaturated hydrocarbons that has not been fully explored. The result is beneficial for clarifying the non-equilibrium reactions involved in the formation of organic nitriles, guiding researchers to have a more comprehensive understanding of the formation of organic nitriles.

Figures and Tables | References | Related Articles | Metrics
Trade-off between species diversity and interaction complexity in the soil bacterial communities of Tiantong forest
Congling ZHANG, Jing YANG, Xihua WANG, Yu LIU, Guochun SHEN
2025, 2025 (4):  69-76.  doi: 10.3969/j.issn.1000-5641.2025.04.007
Abstract ( 21 )   HTML ( 1 )   PDF (1587KB) ( 5 )  

Based on 1287 soil bacterial community samples from Tiantong’s 20 hm2 forest plot, this study applied the dissimilarity-overlap curve (DOC) analytical framework to the forest soil bacterial system for the first time, using the square of the slope of the fitting line to estimate the interaction complexity and tested Robert May’s stability constraint theory. Results showed that high interaction complexity occurred only when species richness was relatively low, while communities with high species richness tended to show low interaction complexity in Tiantong soil bacterial communities. In addition to species richness, there was a significant trade-off between other species diversity indices (number of top abundance species, Shannon effective species) and interaction complexity. This finding suggests stability constraints and upper interaction complexity limits in natural ecosystems, fostering deeper insight into mechanisms governing soil bacterial ecosystems’ diversity and stability.

Figures and Tables | References | Related Articles | Metrics
Effects of decomposed sheep manure combined with chemical fertilizer on the soil fertility and yield of highland barley fields
Guoying SONG, Zhuoma BIANBA, Guoyi LIU
2025, 2025 (4):  77-83.  doi: 10.3969/j.issn.1000-5641.2025.04.008
Abstract ( 17 )   HTML ( 0 )   PDF (591KB) ( 2 )  

To study the effects of the combined application of decomposed sheep manure organic fertilizer and chemical fertilizer on the soil fertility and yield of highland barley fields (currently treated with conventional fertilization for highland barley planting in the Lhasa agricultural area), four different treatments were prepared for the field experiment by increasing the application of potassium chloride and decomposed sheep manure, and reducing the amount of urea and diammonium phosphate (DAP). The treatments follow: T1 conventional fertilization (sheep manure 5250 kg/hm2+ urea 180 kg/hm2 + DAP 180 kg/hm2), T2 (sheep manure 5250 kg/hm2 + urea 150 kg/hm2+ DAP 120 kg/hm2 + potassium chloride 30 kg/hm2), T3 (sheep manure 10500 kg/hm2 + urea 150 kg/hm2 + DAP 120 kg/hm2 + potassium chloride 30 kg/hm2), and T4 (sheep manure 15750 kg/hm2 + urea 135 kg/hm2 + DAP 75 kg/hm2 + potassium chloride 30 kg/hm2). The results showed that soil organic matter, total nitrogen, and total potassium decreased after harvesting compared with the situation before planting according to different fertilization modes. The available nitrogen, phosphorus, potassium, and pH of T3 increased slightly after harvesting compared with their levels before planting. Total and available phosphorus in T1 also increased after harvesting compared with their levels before planting. The height and biomass of highland barley were higher in the mature stage after applications of T1 and T4 treatments. With an increase in the proportion of decomposed sheep manure instead of chemical fertilizer, the yield of highland barley initially increased and then decreased. When the fertilizer substitution rate for T3 reached 16.67%, the yield of highland barley reached 5323.65 kg/hm2. Study findings indicate that the combined application of decomposed sheep manure and chemical fertilizer is beneficial for improving the fertilizer supply capacity of soil and increasing the yield of highland barley. This study provides a reference for rational fertilization and the reduction of non-point source pollution in highland barley fields in Tibet.

Figures and Tables | References | Related Articles | Metrics
Analysis of the effectiveness of small-scale habitat construction for wild animals in Shanghai: A case study of a bird habitat in Wusong River
Yunlu QIAO, Jiayi Wang, Hongwei WANG, Weiyu YU, Yiyun YUAN
2025, 2025 (4):  84-92.  doi: 10.3969/j.issn.1000-5641.2025.04.009
Abstract ( 14 )   HTML ( 0 )   PDF (661KB) ( 1 )  

This study used the renovated Wusong River bird habitat in Shanghai to explore the effectiveness of constructing small-scale habitats for wild animals in Shanghai. The diversity and seasonal dynamics of birds in the Wusong River habitat for birds were analyzed using line transect method and direct counting methods. Fifty-four bird species in 10 orders and 29 families were recorded, including 11 species of waterfowl, 38 species of finches, and one species of bird protected at national level Ⅱ. Among the various residence types of birds, 28(51.9%), 15(27.8%), 6(11.1%), and 5(9.3%) species of resident, wintering, summering, and traveling birds, respectively, were recorded. Among the various bird lineages, 23(42.6%) and 17(31.5%) were found at the Palearctic and Oriental boundaries, respectively, while 14(25.9%) species were widespread. The dominant species were the Chinese blackbird, light-vented bulbul, spotted dove, [tree] sparrow, Japanese white-eye, silky starling, yellow-throated bunting, and long-tailed shrike. There was a low population of both summer residents and travelers in the habitat. The bird diversity index was highest in autumn (migration period), followed by winter (overwintering period), spring (migration period), and summer (breeding period), whereas the evenness index was highest in autumn (migration period), followed by spring (migration period), winter (overwintering period), and summer (breeding period). The results confirmed the effectiveness of constructing small-scale habitats for wild animals in Shanghai, and recommendations for the construction and management of such habitats are proposed.

Figures and Tables | References | Related Articles | Metrics
Population genetics of the flat-headed bats in Southern China
Jie ZHANG, Panyu HUA
2025, 2025 (4):  93-103.  doi: 10.3969/j.issn.1000-5641.2025.04.010
Abstract ( 13 )   HTML ( 1 )   PDF (1717KB) ( 5 )  

Flat-headed bat (Tylonycteris pachypus), an insectivorous bat species, roosts in bamboo forests. In this study, 450 T. pachypus individuals were sampled from 16 sites across Guangdong, Guangxi, and other locations. Genotyping was performed using 19 microsatellite loci. Genetic diversity analyses revealed that T. pachypus maintained a high level of genetic diversity. Bottleneck detections indicated that two populations, Hekeng in China and Selangor in Malaysia, experienced historical bottleneck effects. Isolation by distance analyses demonstrated that geographical distance exerted an obstructive effect on gene flow in T. pachypus. STRUCTURE genetic clustering analyses divided all populations into five genetic clades, and no significant gene flow was detected among them. In conclusion, this study elucidated the genetic diversity patterns of the T. pachypus, providing reasonable suggestions for T. pachypus conservation.

Figures and Tables | References | Related Articles | Metrics
Study on bacterial community structure in the intestine of Litopenaeus vannamei and its cultivation environment
Qin JIN, Chuwen QIU, Xincheng YUAN
2025, 2025 (4):  104-113.  doi: 10.3969/j.issn.1000-5641.2025.04.011
Abstract ( 11 )   HTML ( 0 )   PDF (2599KB) ( 2 )  

The aim of this study was to compare the bacterial community structure of Litopenaeus vannamei in different cultivation environments. An Illumina MiSeq high-throughput sequencing-based method was used for detecting the 16S rRNA gene of the bacterial community in the intestine of L. vannamei and water and sediment samples from cultivation ponds. The results showed that the bacterial community in the intestine of L. vannamei and in the cultivation environment included 62 phyla, 175 classes, 381 orders, 631 families, 1141 genera, and 2035 species. Proteobacteria, Actinobacteriota, and Chloroflexi were the dominant bacterial phyla in the intestine of L. vannamei, with average percentages of 33.67%, 25.33%, and 12.77%, respectively. Proteobacteria, Chloroflexi, and Firmicutes were the dominant bacteria in the sediments, accounting for 28.33%, 17.33%, and 11.13%, respectively. The dominant bacteria in the water were Actinobacteria, Cyanobacteria, and Proteobacteria, with average percentages of 29.33%, 27.0%, and 21.33%, respectively. The abundance-based coverage estimator (ACE) and Chao diversity index of bacterial community in the intestine of L. vannamei were higher than those in the water, while lower than those in the sediments. The bacterial community richness in the intestine of L. vannamei was similar to that in water, but higher than that in the sediments. The Shannon index of the bacterial community in the intestine of L. vannamei was higher than that in the sediments, but lower than that in water. The Simpson index of the bacterial community in the intestine of L. vannamei was higher than that in the sediments but lower than that in the water. Nevertheless, some dominant bacterial species were similar in the intestine of L. vannamei and in the cultivation environment. At the operational taxonomic unit (OTU) level, 1492 identical units were detected in the intestines of L. vannamei and sediments, and 588 identical units were detected in the intestine of L. vannamei and water. Both cluster and principal coordinate analyses showed that the bacterial community in the intestine of L. vannamei was relatively similar to that in the sediments. This study explored the relationship between the bacterial community in the intestine of L. vannamei and its cultivation environment, providing valuable data for the scientific use of environmental probiotics, quality and production, and disease and epidemic prevention.

Figures and Tables | References | Related Articles | Metrics
Preparation and performance evaluation of Ca2+ ion treatment agent for oilfield drilling wastewater
Wenfeng TAN, Xiao JIA, Xun YANG, Xin LI, Yifan GUO, Yuanpeng CHENG, Shanfa TANG
2025, 2025 (4):  114-123.  doi: 10.3969/j.issn.1000-5641.2025.04.012
Abstract ( 17 )   HTML ( 0 )   PDF (843KB) ( 0 )  

In order to improve the water solubility of chitosan and its chelating ability to metal ions, a Ca2+ ion treatment agent for drilling wastewater of shale gas field was successfully prepared by grafting acrylic acid (AA) onto water soluble chitosan (KJT-1) with high deacetylation degree (98%) using the potassium persulfate (KPS) as initiator. The synthesis reaction conditions (temperature, reaction time, initiator and acrylic acid dosage) were optimized using single factor experimental method with Ca2+ removal rate in wastewater as the optimization target, the synthesized product of the optimal synthesis reaction conditions was structurally characterized using Fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance spectroscopy (NMR) and evaluated for the effect on the removal of multivalent ions from simulated drilling wastewater. The results showed that the optimal synthetic reaction conditions for acrylic acid graft-modified water-soluble chitosan were chitosan∶potassium persulfate = 1∶1.2 (mass ratio), chitosan∶acrylic acid = 1∶25 (mass ratio), reaction time of 2 h, and reaction temperature of 70 ℃, the synthetic product (HCCLJ) under these conditions was consistent with the design of the molecular structure of the target product. When the amount of HCCLJ was added at 600 mg/L, the Ca2+ ion content in simulated water can be reduced from 1101 mg/L to 194 mg/L, and the calcium ion removal rate was 82.4%. The removal effect of different HCCLJ dosages on other multivalent ions was in the following order: total iron (Fe2+/Fe3+) > Ba2+ > Mg2+ > Al3+. HCCLJ can not only remove Ca2+ ion, but also have a certain removal effect on other multivalent ions, which has a multi-effect function, and lays a foundation for the research and development of multivalent ions removal agent for oilfield drilling wastewater with a broad application prospect.

Figures and Tables | References | Related Articles | Metrics
Application of Differential Scanning Calorimetry in honey adulteration
Mingxia CHAI, Mengyao LYU, Mingchao ZHANG
2025, 2025 (4):  124-133.  doi: 10.3969/j.issn.1000-5641.2025.04.013
Abstract ( 9 )   HTML ( 0 )   PDF (1569KB) ( 0 )  

This study explored the feasibility of applying Differential Scanning Calorimetry (DSC) to identify adulteration in five honey samples from Qinghai and neighboring regions. Adulterated samples with adulteration levels (syrup mass/honey mass) ranging from 0, 0.05, 0.1, 0.15, $\cdots $, to 0.95 were prepared using fructose-glucose syrup or maltose syrup as adulterants. DSC curves were generated to analyze the relationship between DSC signals and temperature. SPSSPRO software was used for modeling, employing a stepwise regression method to establish models for the glass transition onset (Tg0) and midpoint (Tgm). Significance analysis revealed the following: for nitraria honey adulterated with fructose-glucose syrup, the significance level exceeded 0.05. When adulterated with maltose syrup, the Tgm during the cooling phase showed a significance level > 0.05. For goji berry honey adulterated with fructose-glucose syrup, Tgm in the cooling phase was also a key parameter. For other samples, Tg0 and Tgm during the heating phase demonstrated strong significance. These results indicate that combining DSC data with modeling methods is efficient and accurate for honey adulteration identification. However, no consistent patterns were observed among different honey types.

Figures and Tables | References | Related Articles | Metrics
Evaluation of biochar-desulfurized gypsum mixed application on saline-alkali soil improvement and N2O emission reduction in coastal areas
Ziyan CHEN, Rongrong YANG, Yi WU, Lijun HOU, Xia LIANG
2025, 2025 (4):  134-146.  doi: 10.3969/j.issn.1000-5641.2025.04.014
Abstract ( 29 )   HTML ( 0 )   PDF (923KB) ( 1 )  

The effects of biochar and desulfurized gypsum (FGD) on the improvement of coastal saline-alkaline soils and the emission of nitrous oxide (N2O) from soils were quantitatively evaluated using different application ratios of biochar and FGD under laboratory conditions and combined with stable isotope and molecular biology methods. The results showed that compared with the treatment with biochar or FGD gypsum alone, soil exchangeable eodium saturation percentage (ESP) decreased significantly to 11.6% ~ 13.0% whereas soil organic carbon content increased by about 34 times after the application of the mixture. Compared with the control and the individual applications, cumulative soil N2O emission in the mixture treatment decreased by about 127.7%. This is mainly due to the fact that the mixture application of biochar and FGD gypsum can significantly increase the nitrification and denitrification potential of soil as well as the consumption of soil N2O, thereby effectively reducing the soil N2O emission. The results of this study provide data support and a theoretical basis for the development of coastal saline soil improvement technology and the management of soil greenhouse gas emissions.

Figures and Tables | References | Related Articles | Metrics
Analysis of erosion–deposition processes and mechanisms during flood–ebb and spring–neap tides over the mouth bar shoal on the northern side of Chongming Dongtan
Zijie TAN, Shujie NIU, Maotian LI, Weihua LI, Xiaoqiang LIU, Yan SONG, Huikun YAO, Wenyan ZHANG, Dan PENG, Xinjie CHEN
2025, 2025 (4):  147-157.  doi: 10.3969/j.issn.1000-5641.2025.04.015
Abstract ( 9 )   HTML ( 0 )   PDF (1528KB) ( 0 )  

The erosion-deposition processes of estuarine bars are the basis of estuarine geomorphology and channel evolution. Most studies revealed the annual or seasonal change in deposition-erosion of estuarine bars based on chart data and sedimentary dating. However, understanding of erosion-deposition changes during the flood-ebb tide and spring-neap tide cycles is insufficient. This study conducted high-resolution in-situ observations of hydrodynamics and bedform changes on the tidal flat front of northern Chongming Dongtan, using bottom-mounted tripods over 15 flood–ebb tide cycles and one spring–neap tide cycle. The study found increases and decreases in velocity in four erosion-deposition phases over one flood-ebb cycle: flood tide erosion, flood tide deposition, ebb tide erosion, and ebb tide deposition. In addition, the flood flow originating from offshore shoals caused a high suspended sediment peak (SSP), which settled rapidly and formed the major silting layer after flood slack. The ebb flow caused another SSP and formed the major scouring layer due to long-term scouring by high velocity flow during the rapid ebb flow stage. From neap tide to spring tide, the bed exhibited a scouring trend due to the generally low suspended sediment concentration (SSC) of flood flow from offshore shoals. However, from spring tide to neap tide, the bottom showed a depositional trend due to a high and increasing SSC of flood flow from shoals. The above findings provide a reference for further understanding of estuarine erosion-deposition and evolution processes.

Figures and Tables | References | Related Articles | Metrics
High-precision tidal level prediction in the photovoltaic field offshore the Yellow River estuary
Cansheng YE, Minggao ZHAI, Jianrong ZHU
2025, 2025 (4):  158-169.  doi: 10.3969/j.issn.1000-5641.2025.04.016
Abstract ( 14 )   HTML ( 0 )   PDF (8376KB) ( 2 )  

For the construction of offshore photovoltaic fields in ultra-shallow water, tidal level prediction is required to ensure the safety of construction vessels and the smooth progress of the project. In this study, continuous tidal level observations were conducted for over three months at the HG14 offshore photovoltaic field off the Yellow River estuary. Based on the measured tidal data, tidal harmonic analysis was performed, and tidal harmonic analysis prediction at the observation station was conducted. Numerical prediction of tidal level was conducted based on the establishment of the hydrodynamic model of the Bohai Sea and validation of the model. The measured data of the tidal level indicate that the tides in the photovoltaic field are irregular semi-diurnal mixed tides, with significant diurnal inequality and maximum tidal range of approximately 2.0 m. Harmonic analysis of the 11 major tidal constituents indicates that their amplitudes from large and small are M2, K1, O1, S2, K2, P1, N2, M4, Q1, MS4, and M6, with respective amplitudes of 62.28, 26.27, 22.06, 20.87, 7.49, 6.64, 6.36, 5.11, 4.28, 1.47, and 0.65 cm. The amplitude of M2 is 62.28 cm, approximately 2.37 times that of the second-largest constituent K1 (26.27 cm). The amplitude of the semi-diurnal constituent S2 is 20.87 cm, which is smaller than those of the diurnal constituents K1 and O1. Among the three shallow-water tidal constituents, M4 is the largest, while MS4 and M6 are significantly smaller than M4. After obtaining the harmonic constants of the major tidal constituents, harmonic analysis tidal predictions were conducted at the observation station. The results show that the consistency between the harmonic analysis predicted tidal level and measured tidal level is very good. The technical scores of the predicted tidal level by harmonic analysis and the numerical simulated tidal level between the measured tidal level are 0.96 and 0.97, respectively, and both can predict the tidal level with high accuracy. The validated numerical model was applied to simulate and predict tidal levels at the model output point in the photovoltaic field. Temporal variation figures of tidal level and tide tables in each month were presented. The diurnal inequality in the photovoltaic field is particularly distinct during neap tides, with low tide levels noticeably higher than those during spring tides. The tide tables provide hourly tidal levels for each day at the output point in three dates of Gregorian, lunar, and weekday, as well as the two daily high- and low-tide levels and their corresponding times. This study indicated the tidal characteristics in the offshore photovoltaic field HG14. The predicted tidal levels can provide scientific guidance for construction vessels to avoid shallow grounding.

Figures and Tables | References | Related Articles | Metrics