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Feasibility analysis of a single-sensor-based approach for source identification of hazardous chemical releases

Chinese Journal of Chemical Engineering 2019年第7期27卷 1642-1650页

作者： Zengqiang Chen Lian Ye Bo Dai Fang Wang College of Information Engineering Beijing Institute of Petrochemical TechnologyBeijing 102617China School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China office of academic affairs Beijing Institute of Petrochemical TechnologyBeijing 102617China

Source identification is critical for emergency responses to hazardous chemical releases,especially sudden releases of toxic gases.The timely arrangement of multiple sensors at the scene of a sudden accident is difficult.To overcome this limitation,a two-step source identification method based on a single sensor was developed.In the first step,the measured concentration was transmitted to the computing platform.First,a preliminary estimation of the release source was calculated from recently detected concentrations.Then,the preliminary result was used to predict the concentrations and to assess whether more measurements were needed.This data processing was conducted by the computing platform.In the second step,a new objective monitoring point was transmitted to the detector for the measurement of additional concentrations.These two steps were conducted repeatedly until the estimation adequately represented the release source.The fixed and mobile single sensor results were analyzed,and a comparison to multi-sensor results was also conducted.The results show that single-sensor source identification is attainable with a sufficient number of observations,and the number of valid concentration observations is required to be no less than the number of unknown parameters.To best estimate the release source,the movement strategy of the single sensor was based on the possible release source and the hazard partition of the gas plume.It is highly recommended that the single-sensor source identification method be used in unexpected incidents due to its flexibility and timely response.

关键词： Safety analysis Emergency response Inverse problems Optimization Dispersion model

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Modified (2+1)-dimensional displacement shallow water wave system and its approximate similarity solutions

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Chinese Physics B 2011年第9期20卷 30-36页

作者：刘萍付培凯 Department of Electronic Engineering University of Electronic Science and Technology of China Zhongshan Institute academic affairs Division Zhongshan Polytechnic

Recently, a new （2＋1）-dimensional shallow water wave system, the （2＋1）-dlmenslonal displacement shallow water wave system （2DDSWWS）, was constructed by applying the variational principle of the analytic mechanics in the Lagrange coordinates. The disadvantage is that fluid viscidity is not considered in the 2DDSWWS, which is the same as the famous Kadomtsev-Petviashvili equation and Korteweg-de Vries equation. Applying dimensional analysis, we modify the 2DDSWWS and add the term related to the fluid viscidity to the 2DDSWWS. The approximate similarity solutions of the modified 2DDSWWS （M2DDSWWS） is studied and four similarity solutions are obtained. For the perfect fluids, the coefficient of kinematic viscosity is zero, then the M2DDSWWS will degenerate to the 2DDSWWS.

关键词： modified （2＋1）-dimensional displacement shallow water wave system viscidity approx-imate similarity solutions Kadomtsev-Petviashvili equation

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The evolution of China’s regulation of agricultural biotechnology

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aBIOTECH 2022年第4期3卷 237-249页

作者： Jingang Liang Xiaowei Yang Yue Jiao Danxia Wang Qiang Zhao Yu Sun Yunhe Li Kongming Wu Development Center of Science and Technology Ministry of Agriculture and Rural AffairsBeijing100176China State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant ProtectionChinese Academy of Agricultural SciencesBeijing100193China Croplife Asia Beijing office Beijing100125China

To ensure safe use of genetically modified organisms(GMOs),since 1993,China has made great efforts to establish and improve the safety regulatory system for GMOs.Here,we summarize and analyze the regulatory framework of agricultural GMOs,and the progress in regulatory approval of GM crops in China.In general,the development of GMO safety regulations underwent four stages:exploration(1993–2000),development(2001–2010),improvement(2011–2020)and current(2021-present)stage.The first formal regulation was promulgated in 1993,which provided a basis for further development of the regulations,during the exploration stage,when insect-resistant GM cotton,expressing genes from Bacillus thuringiensis(Bt),was approved for cultivation.During the development stage,the Chinese government issued a series of administrative measures,which covered almost all the fields relative to GMO safety when the basic regulatory system was established.Along with the controversy over GMO safety,the regulations have been further,and greatly improved,during improvement stage.From 2021,a few additional revisions have been made,and meanwhile,the new regulation on gene-edited crops was introduced with the development of biotechnology,forming a relative complete regulation and law system for China.The well-developed GMO regulations establishes a firm basis for safe use of GM crops in China.Currently,GM cotton and GM papaya have been widely grown on a large scale in China that have brought great economic and ecological benefits.In addition,12 corn events,3 soybean events,and 2 rice events have also obtained biosafety certification,but presently,these lines have yet to enter commercial production.However,several GM soybean and corn events have entered pilot industrialization,and can soon be expected to be commercially grown in China.In addition to planting,six GM crops,including soybean,corn,cotton,canola,papaya and sugar beet,with a total of 64 events,have been approved for import as processing material in China.

关键词： Genetically modified organisms Biosafety certificate Regulatory approval Gene editing Pilot phase

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Graph Enhanced Transformer for Aspect Category Detection

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Journal of Computer Science & Technology 2023年第3期38卷 612-625页

作者：陈晨王厚峰朱晴晴柳军飞 office of the Cyberspace affairs Commission Peking UniversityBeijing 100871China School of Computer Science Peking UniversityBeijing 100871China School of Software and Microelectronics Peking UniversityBeijing 100871China National Engineering Research Center for Software Engineering Peking UniversityBeijing 100871China

Aspect category detection is one challenging subtask of aspect based sentiment analysis, which categorizes a review sentence into a set of predefined aspect categories. Most existing methods regard the aspect category detection as a flat classification problem. However, aspect categories are inter-related, and they are usually organized with a hierarchical tree structure. To leverage the structure information, this paper proposes a hierarchical multi-label classification model to detect aspect categories and uses a graph enhanced transformer network to integrate label dependency information into prediction features. Experiments have been conducted on four widely-used benchmark datasets, showing that the proposed model outperforms all strong baselines.

关键词： aspect based sentiment analysis aspect category detection hierarchical multi-label classification transformer network

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The New Historical Divide of Online Education:Dialogues with Key Leaders During the Epidemic

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ECNU Review of Education 2020年第4期3卷 755-761页

作者： Xiaolei Zhang Xiaoxiao Wang Manli Li School of Education Tianjin University office of Lifelong Education Administration Undergraduate Academic AffairsTsinghua University Institute of Education Tsinghua UniversityBeijingChina

The Coronavirus epidemic has reached far deeper into people’s daily life across the world,with the sweeping shutdown of all schools and the educational upheaval of students globally.“The speed and scale of the educa... 详细信息

关键词： has globally shutdown

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Rural E-commerce and County Economic Development in China

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China & World Economy 2023年第5期31卷 26-60页

作者： Qiuxia Qin Hongdong Guo Xinjie Shi Kevin Chen China Academy for Rural Development School of Public AffairsZhejiang UniversityChina China Academy for Rural Development School of Public AffairsChina and Research Center for Common ProsperityFuture Regional Development LaboratoryInnovation Center of Yangtze River DeltaZhejiang UniversityChina China Academy for Rural Development School of Public AffairsZhejiang UniversityChina and International Food Policy Research InstituteEast and Central Asia OfficeChina

With the proliferation of information and communication technology in rural areas,rural e-commerce has gradually become a new economic phenomenon in China. Usingthe national rural e-commerce comprehensive demonstration policy as a quasi-naturalexperiment, this study examines the causal linkage between rural e-commerce andcounty-level economic development in China. Its findings, which draw on county-levelpanel data from 2011 to 2018, indicate that the policy had a positive effect on the countyleveleconomy in China, resulting in an overall increase in county GDP by 3.5 percent(0.7 percent annually). Our analysis further shows that the impact of the policy diferedalong the region and human capital dimensions. Further analysis reveals that industrialstructure and nonagricultural employment were the main channels for the policy toexert a county-level economic impact. Infrastructure improvement in China also playsan important role. The findings emphasize the importance of advancing e-commerce inrural areas to stimulate county-level economic development.

关键词： county economy e-commerce quasi-natural experiment rural China

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A Coupled Hybrid Lattice: Its Related Continuous Equation and Symmetries

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Communications in Theoretical Physics 2011年第7期56卷 5-10页

作者：刘萍付培凯 Department of Electronic Engineering University of Electronic Science and Technology of China Zhongshan Institute academic affairs Division Zhongshan Polytechnic

The hybrid lattice, known as a discrete Korteweg-de Vries (KdV) equation, is found to be a discrete modified Korteweg-de Vries (mKdV) equation in this paper. The coupled hybrid lattice, which is pointed to be a discrete coupled KdV system, is also found to be discrete form of a coupled mKdV systems. Delayed differential reduction system and pure difference systems are derived from the coupled hybrid system by means of the symmetry reduction approach. Cnoidal wave, positon and negaton solutions for the coupled hybrid system are proposed.

关键词：混合动力系统连续方程自耦合对称性 KDV系统离散形式德弗里斯椭圆余弦波

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Potential friendship discovery in social networks based on hybrid ensemble multiple collaborative filtering models in a 5G network environment

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Digital Communications and Networks 2022年第6期8卷 868-876页

作者： Hexuan Hu Zhenzhou Lin Qiang Hu Ye Zhang Key Laboratory of Water Big Data Technology of Ministry of Water Resources Hohai UniversityNanjingChina College of Computer and Information Hohai UniversityNanjingChina office of Teaching affairs Nanjing University of Finance and EconomicsNanjingChina Electric Engineering College Tibet Agriculture&Animal Husbandry UniversityTibetChina

At present, 5G network technology is being applied to various social network modes, and it can provide technical and traffic support for social networks. Potential friendship discovery technology in 5G-enabled social networks is beneficial for users to make potential friends and expand their range of activities and social hierarchy, which is highly sought after in today's social networks and has great economic and application value. However, the sparsity of the dominant user association dataset in 5G-enabled social networks and the limitations of traditional collaborative filtering algorithms are two major challenges for the friend recommendation problem. Therefore, in order to overcome these problems regarding previous models, we propose a Hybrid Ensemble Multiple Collaborative Filtering Model (HEMCF) for discovering potential buddy relationships. The HEMCF model draws on a special autoencoder method that can effectively exploit the association matrix between friends and additional information to extract a hidden representation of users containing global structural information. Then, it uses the random walk-based graph embedding algorithm DeepWalk to extract another hidden representation of users in the buddy network containing local structural information. Finally, in the output module, the HEMCF model stacks and multiplies the two types of hidden representations of users to ensure that the information mentioned above is concentrated in the final output to generate the final prediction value. The magnitude of the prediction value represents the probability of the users being friends, with larger values representing a high probability of the two users being friends, and vice versa. Experimental results show that the proposed method boosts the accuracy of the relationship prediction over baselines on 3 real-world public datasets dramatically.

关键词： 5G network Social network Collaborative filtering Recommendation system Friendship discovering

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Transcriptional Features of Cattle Visceral and Subcutaneous Adipose Tissues: A Study of RNA-seq

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Open Journal of Animal Sciences 2022年第3期12卷 441-453页

作者： Xiaoyan Duan Yu Liu Xiaoxiao Zhang Haiyi Zhao office of academic affairs Hebei North University Zhangjiakou China Department of Laboratory Animal Center Hebei North University Zhangjiakou China Key Laboratory of Experimental Animals of Hebei Province Shijiazhuang China Hebei North University Zhangjiakou China

Visceral and subcutaneous are the two major types of bovine adipose tissues, and they show metabolic and functional differences according to their distribution, exploring the transcriptional features of visceral and subcutaneous adipose tissues is necessary. In the present study, we conducted RNA-seq analysis to compare the transcriptome between visceral (great omental) and subcutaneous (backfat) adipose tissues from Chinese Simmental cattle and validate them by qRT-PCR. We found that 5864 genes were differentially expressed between two tissues, including 2979 up-regulated and 2885 down-regulated in visceral adipose tissue. Functional analysis revealed a variety of differentially expressed genes (DEGs) involved in lipid metabolism and immune response processes. This may provide valuable information to further our understanding of the complexity of gene regulation governing the physiology of different fat depots. This work highlighted potential genes regulating lipid metabolism and immune responses;it may contribute to a better understanding of the metabolic and functional differences between visceral and subcutaneous adipose tissues.

关键词： Visceral Adipose Tissue Subcutaneous Adipose Tissue Transcriptional Features Cattle

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The protective effect of icariin on glucocorticoid-damaged BMECs explored by microfluidic organ chip

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Chinese Chemical Letters 2022年第6期33卷 3177-3182页

作者： Tengqi Li Qingyu Zhang Fuqiang Gao Yadi Liu Wei Sun Yiyang Dong Department of Orthopedics Peking University China-Japan Friendship School of Clinical MedicineBeijing 100029China Department of Orthopedics Peking University Shougang HospitalBeijing 100144China Department of Orthopedics Shandong Provincial Hospital Affiliated to Shandong First Medical UniversityJi’nan 250021China Department of Orthopedics China-Japan Friendship HospitalBeijing 100029China office of academic affairs Beijing University of Chemical TechnologyBeijing 100029China Department of Pharmaceutical Analysis College of Life Science and TechnologyBeijing University of Chemical TechnologyBeijing 100029China

Osteonecrosis of the femoral head(ONFH)is a devastating musculoskeletal disease characterized by the impaired circulation of bone.The purpose of this study was to explore the underlying mechanisms of the protective effect of icariin on the glucocorticoid-induced injury of bone microvascular endothelial cells(BMECs).Normal BMECs were extracted from the femoral heads by enzymatic isolation and magneticactivated cell sorting methods.Dexamethasone and icariin were used to intervene BMECs in microfluidic organ chips,and phalloidin staining was conducted to observe the cell morphology and viability.Then next-generation transcriptome sequencing and real-time quantitative reverse transcription-polymerase chain reaction(q RT-PCR)were performed to identify the differentially expressed genes(DEGs)in different groups.Through the microfluidic organ chip,it can be observed that after dexamethasone intervention,the filamentous structure in cell fibers disappeared and the cell morphology changed from spindle to round until death.Icariin could relieve these changes and showed a protective effect on glucocorticoiddamaged BMECs.In addition,201 DEGs were detected between the icariin protection group and the dexamethasone group,which were significantly enriched in 17 signaling pathways.8 of the top ten selected hub genes(IL6,PTGS2,VEGFA,etc.)were confirmed by q RT-PCR.Transcription factors(TFs)-gene network showed 63 connections between 18 TFs and 12 DEGs.For instance,GATA2 could regulate 5 DEGs.The associations between 92 mi RNA and 12 DEGs were visualized in a mi RNA-gene network.The hub mi RNA,has-mir-335–5 p was predicted to interact with 8 DEGs(PTGS2,VEGFA,etc.).Microfluidic organ chips could provide excellent morphological results for cell experiments,by which it could be observed that icariin showed a protective effect on the glucocorticoid-induced injury of BMECs.Beside,these DEGs,possible regulatory TF(GATA2,FOXC1,etc.)and mi RNA(has-mir-335–5 p)might be dysregulated in the initiation of ONFH and have prospective importance

关键词： Osteonecrosis of the femoral head Bone microvascular endothelial cells Glucocorticoid Microfluidic chip Bioinformatic analysis

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