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中华医学杂志(英文版) 2024年第15期137卷 1882-1884页

作者： Yin Yuyao Shen Jiawei Du Zhenshan wang Bin wang guangjie Chen Hongbin wang Jun An Youzhong Liu Chao wang Hui Department of Clinical Laboratory Peking University People’s Hospital Beijing China Department of Critical Care Medicine Peking University People’s Hospital Beijing China Medical Department Hangzhou Matridx Biotechnology Co. Ltd. Hangzhou Zhejiang China

基于拉格朗日混合单粒子轨迹模式(HYSPLIT)的核污染物扩散数值预报技术

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辐射研究与辐射工艺学报 2024年第2期42卷 106-115页

作者：王广杰沈红李娟兰伟仁管维彪 61741部队北京100082

本研究利用拉格朗日混合单粒子轨迹模式(HYSPLIT)开展了核污染物数值预报试验。欧洲示踪试验和虚拟事故情景下的模拟预报试验结果表明,HYSPLIT模式模拟的1h内轨迹最小绝对误差约为0.2°,该模式可以有效地预报核污染物的扩散轨迹。模拟... 详细信息

本研究利用拉格朗日混合单粒子轨迹模式(HYSPLIT)开展了核污染物数值预报试验。欧洲示踪试验和虚拟事故情景下的模拟预报试验结果表明,HYSPLIT模式模拟的1h内轨迹最小绝对误差约为0.2°,该模式可以有效地预报核污染物的扩散轨迹。模拟轨迹误差主要受风向和风速的影响,且初始状态误差会使轨迹模拟的误差随着预报时效增加而逐渐增大;对于单次轨迹模拟,模式模拟轨迹会存在偏差,但在一定时间范围内,轨迹模拟可以很好反映示踪剂在释放后空间范围内整体的分布特征;利用大气扩散模式HYSPLIT和中尺度天气预报模式(WRF),可以实现区域核污染物的数值预报,模式可以预报出事故区域核泄漏物质的扩散路径和浓度分布。

关键词：拉格朗日混合单粒子轨迹模式(HYSPLIT) 核污染物欧洲示踪试验数值预报

Detecting JPEG image forgery based on double compression

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Journal of Systems Engineering and Electronics 2009年第5期20卷 1096-1103页

作者： wang Junwen Liu guangjie Dai Yuewei wang Zhiquan School of Automation Nanjing Univ. of Science &: Technology Nanjing 210094 P. R. China

Detecting the forgery parts from a double compressed image is very important and urgent work for blind authentication. A very simple and efficient method for accomplishing the task is proposed. Firstly, the probabilistic model with periodic effects in double quantization is analyzed, and the probability of quantized DCT coefficients in each block is calculated over the entire iraage. Secondly, the posteriori probability of each block is computed according to Bayesian theory and the results mentioned in first part. Then the mean and variance of the posteriori probability are to be used for judging whether the target block is tampered. Finally, the mathematical morphology operations are performed to reduce the false alarm probability. Experimental results show that the method can exactly locate the doctored part, and through the experiment it is also found that for detecting the tampered regions, the higher the second compression quality is, the more exact the detection efficiency is.

关键词： image forgery JPEG double compression quantization posteriori probability.

The 3-D structure of shear wave in South China and the southward extension of Tanlu fault

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Chinese Science Bulletin 2001年第4期46卷 284-289页

作者： TENG Jiwen wang guangjie ZHANG Zhongjie HU Jiafu Institute of Geology and Geophysics Chinese Academy of SciencesBeijing 100101China Yunnan University Kunming 650091China

By processing the CSND Rayleigh wave data with the matched filter FTAN technique, Rayleigh wave dispersion for southeast China is obtained. The 4°×4°S wave dispersion of the pure path is calculated using random inversion scheme, and 3-D S wave velocity structure is set up. Incorporating the above-mentioned results with wide angle seismic sounding data, we studied structure framework and the extending of faults in this area, which demonstrates that the depth of Moho in South China varies from 30 to 40 km, shallower from west to east. The depth of Moho varies from 25 to 28 km for the offshore. The depth of the asthenosphere in upper mantle varies from 60 to 100 km. The depth difference of layers at the two sides of Tanlu fault is more than 10 km at the south part of the Yangtze River, and the fault extends downward more than 170 km. The fault exceeds the main land at Hainan Island and slips into the southern China Sea. Both Tanlu fault and the huge bend of gravity gradient anomaly are influenced by

关键词： seismic surface wave Moho mantle cover layer as-thenosphere 3-D velocity structure Tanlu fault.

PHOTOREALISTIC COMPUTER GRAPHICS FORENSICS BASED ON LEADING DIGIT LAW

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Journal of Electronics(China) 2011年第1期28卷 95-100页

作者： Xu Bo wang Junwen Liu guangjie Dai Yuewei School of Automation Nanjing University of Science ＆ Technology Nanjing 210004 China

As the advent and growing popularity of image rendering software,photorealistic computer graphics are becoming more and more perceptually indistinguishable from photographic *** the faked images are abused,it may lead to potential social,legal or private *** this end,it is very necessary and also challenging to find effective methods to differentiate between *** this paper,a novel leading digit law,also called Benford's law,based method to identify computer graphics is *** specifically,statistics of the most significant digits are extracted from image's Discrete Cosine Transform(DCT) coefficients and magnitudes of image's gradient,and then the Support Vector Machine(SVM) based classifiers are *** of experiments on the image datasets indicate that the proposed method is comparable to prior ***,it possesses low dimensional features and low computational complexity.

关键词： Leading digit law Benford’s law Digital image forensic Computer graphics

Boosting Adversarial Training with Learnable Distribution

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Computers, Materials & Continua 2024年第3期78卷 3247-3265页

作者： Kai Chen Jinwei wang James Msughter Adeke guangjie Liu Yuewei Dai School of Electronics and Information Engineering Nanjing University of Information Science and TechnologyNanjing210044China Key Laboratory of Intelligent Support Technology for Complex Environments Ministry of EducationNanjing210044China School of Computer and Software Nanjing University of Information Science and TechnologyNanjing210044China Nanjing Center for Applied Mathematics Nanjing211135China

In recent years,various adversarial defense methods have been proposed to improve the robustness of deep neural *** training is one of the most potent methods to defend against adversarial ***,the difference in the feature space between natural and adversarial examples hinders the accuracy and robustness of the model in adversarial *** paper proposes a learnable distribution adversarial training method,aiming to construct the same distribution for training data utilizing the Gaussian mixture *** distribution centroid is built to classify samples and constrain the distribution of the sample *** natural and adversarial examples are pushed to the same distribution centroid to improve the accuracy and robustness of the *** proposed method generates adversarial examples to close the distribution gap between the natural and adversarial examples through an attack algorithm explicitly designed for adversarial *** algorithm gradually increases the accuracy and robustness of the model by scaling ***,the proposed method outputs the predicted labels and the distance between the sample and the distribution *** distribution characteristics of the samples can be utilized to detect adversarial cases that can potentially evade the model *** effectiveness of the proposed method is demonstrated through comprehensive experiments.

关键词： Adversarial training feature space learnable distribution distribution centroid

2D numerical study on the effect of conductor between the transmitter and survey area in CSEM exploration

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Applied Geophysics 2009年第4期6卷 311-318,393页

作者：王若王妙月底青云王光杰中科院地质与地球物理研究所中国北京100029

In CSEM exploration, the receivers are generally located about three to five times the skin depth from the transmitter. In this paper, we study the effect of a conductor between the transmitter and the survey area on the target conductor response using forward modeling and inversion. The 2D forward finite element calculations show that the conductor mainly affects the response at middle and low frequencies. The lower the resistivity and the larger the conductor, the larger the effect and the effect increases with decreasing frequency. The inversion results indicate that the calculated position of the target body can move towards the source, leading to an incorrect interpretation without considering the conductor. In order to reduce the effect of a conductor between the source and the survey area, CSEM acquisition should be conducted in three dimensions using multiple sources and 3D inversion should be used during interpretation.

关键词： CSEM exploration 2D line source low resistivity body forward modeling inversion

A NEW HEAT-TREATMENT PROCESS FOR 2014 ALUMINUM ALLOY AND ITS MECHANISM

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中国有色金属学会会刊：英文版 1993年第3期3卷 42-47页

作者： wang, Lingyun Huang, guangjie Chao, Denju Chongqing Univsrsity, Chongqing 630044, China

The plan of heat-treatment process for 2014Al alloy is designed using orthogonal method, the heat-treatment experiments are made and the mechanical properties are tested according to the designed plan. The effect of solid solution temperature, ageing temperature, ageing time on microscopic mechanism of the mechanical properties of the 2014Al alloy is studied using microscope, transmission electron microscope. The best heat treatment process of the 2014Al alloy is developed. The experimental results indicate that the strength σb, yield stress σ0.2, percentage elongation δ of the alloy reach separately 490～500 MPa, 450～490 MPa, 10～12％ adopting the new heat treatment process. Compared with GB, the strength increases 20～30％, the percentage elongation increases 30～40％. The mechanism of the new heat-treatment process is also discussed.

关键词： 2014Al new heat treatment process mechanism ultimate tensile strength yield stress percent age elongation

Long‐life lithium batteries enabled by a pseudo‐oversaturated electrolyte

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Carbon Energy 2024年第4期6卷 115-127页

作者： Youchun Yu Simeng wang Juyan Zhang Weiwei Qian Nana Zhang guangjie Shao Haiyan Bian Yuwen Liu Lan Zhang Hebei Key Laboratory of Applied Chemistry College of Environmental and Chemical EngineeringYanshan UniversityQinhuangdaoChina Beijing Key Laboratory of Ionic Liquids Clean Process CAS Key Laboratory of Green Process and EngineeringInstitute of Process EngineeringChinese Academy of SciencesBeijingChina Haike Group Research Institute of Innovation&Technology DongyingChina Langfang Green Industrial Technology Center LangfangChina

The specific energy of Li metal batteries(LMBs)can be improved by using high‐voltage cathode materials;however,achieving long‐term stable cycling performance in the corresponding system is particularly challenging for the liquid ***,a novel pseudo‐oversaturated electrolyte(POSE)is prepared by introducing 1,1,2,2‐tetrafluoroethyl‐2,2,3,3‐tetrafluoropropyl ether(TTE)to adjust the coordination structure between diglyme(G2)and lithium bis(trifluoromethanesulfonyl)imide(LiTFSI).Surprisingly,although TTE shows little solubility to LiTFSI,the molar ratio between LiTFSI and G2 in the POSE can be increased to 1:1,which is much higher than that of the saturation state,1:*** and experimental results prove that TTE promotes closer contact of the G2 molecular with Li^(+)in the ***,it also participates in the formation of electrolyte/electrode *** electrolyte shows outstanding compatibility with both the Li metal anode and typical high‐voltage ***||Li symmetric cells show a long life of more than 2000 h at 1 mA cm^(−2),1 mAh cm^(−2).In the meantime,Li||LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(NCM811)cell with the POSE shows a high reversible capacity of 134.8 mAh g^(−1 )after 900 cycles at 4.5 V,1 C *** concept of POSE can provide new insight into the Li^(+)solvation structure and in the design of advanced electrolytes for LMBs.

关键词： high voltage lithium metal batteries pseudo‐oversaturated electrolyte solid electrolyte interphases(SEI) solvation structure

Application of probability integral method in ground deformation prediction

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Global Geology 2012年第3期15卷 237-240页

作者： wang Zijian LI guangjie YOU Bing BAO Shuochao College of Construction Engineering Jilin University Changchun 130026 China

In order to study the law of mining subsidence and ground movement, to provide the basis of coal mining under building, railway and water, we used the probability integration method to make comprehensive evaluation of ground stability. Take Yingcheng Coal Mine of Jiutai as an example. Mining-induced movement and horizontal movement are analyzed on the basis of the measurement data. The resuhs of prediction can pro- vide reference and basis for prevention of coal mining subsidence and future restoration and treatment.

关键词： surface deformation probability integration method deformation prediction