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Impact of Media Information on Social Response in Disasters:A Case Study of the Freezing‑Rain and Snowstorm Disasters in Southern China in 2008

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International Journal of Disaster Risk Science 2024年第1期15卷 73-87页

作者： Jia He Wenjing duan Yuxuan Zhou Yun Su College of Geographic Science and Tourism Xinjiang Normal UniversityUrumqi 830054China Xinjiang Laboratory of Lake Environment and Resources in Arid Zone Urumqi 830054China Faculty of Geographical Science Beijing Normal UniversityBeijing 100875China Key Laboratory of Environmental Change and Natural Disaster Ministry of EducationBeijing Normal UniversityBeijing 100875China

Disaster information content is an objective mapping of disaster situations,social response,and public *** response to emergency is an important mechanism for implementing and guaranteeing emergency management of major natural hazard-related *** how disaster information content affects social response to emergencies is helpful for managing risk communication and efficient disaster *** on the 2008 freezing-rain and snowstorm disasters in southern China,this study used Python to extract 7,857 case-related media reports and applied natural language processing for text *** used three typical cases to identify and analyze disaster media report content and the relationship between these reports and the social response to the *** categories of disaster response-such as prewarning and forecasting,announcements by the authorities,and social mobilization-appeared in the disaster information in the media,along with disaster impact information,that is,real-time disaster *** response information and an appropriate amount of disaster impact information played important roles in prewarning,disaster relief,public opinion guidance,and social stability maintenance and can serve important functions in communicating with all stakeholders of emergency management,assisting or influencing emergency departments or individuals in decision making,and eliminating "information islands." Empathy caused the general public to become "disaster responders" through receiving *** and an excess of negative information may have a perverse amplification effect on public opinion and increase the unpredictability of the disaster situation and the risk of social crisis.

关键词： Emergency management Freezing-rain and snowstorm disasters Media reports on disasters Social response to emergencies China

CO_(2)capture by modifed clinoptilolite and its regeneration performance

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International Journal of Coal Science & Technology 2024年第2期11卷 81-90页

作者： Bo Jiang Bo Zhang Xuqin duan Yi Xing School of Energy and Environmental Engineering University of Science and Technology BeijingBeijing 100083China Beijing Key Laboratory of Resource-Oriented Treatment of Industrial Pollutants University of Science and Technology BeijingBeijing 100083China YangQuan Coal Industry(Group)Co.Ltd. Yangquan 045000China School of Civil and Resource Engineering University of Science and Technology BeijingBeijing 100083China

This study focuses on CO_(2) capture by pressure swing adsorption(PSA),with modified clinoptilolite as the *** clinoptilolite is modified by roasting,by acid pickling,by a combination of acid pickling and roasting,and by ion *** by acid pickling-roasting and by ion exchange are found to give the highest CO_(2) adsorption capacities,of 730 mL/g and 876.7 mL/g,*** is found that regeneration of clinoptilolite by a combination of vacuum desorption and heating enables recovery of as much as 89%of its previous CO_(2) adsorption *** examine the CO_(2) adsorption capacity of clinoptilolite when applied to mixed gas,a simulated coking exhaust containing 12%CO_(2) and 4%O_(2) is used,and it is found that ion exchange modified clinoptilolite achieves a CO_(2) removal efficiency of 92.5%.A BET test reveals that acid pickling-roasting and Na^(+) modification enhance the porosity of clinoptilolite,thereby improving its adsorption *** work demonstrates the feasibility of applying modified clinoptilolite as an effective adsorbent for COO_(2)capture,providing a promising tool for dealing with greenhouse gases.

关键词： Clinoptilolite Carbon dioxide capture Pressure swing adsorption(PSA)

Patterning single-layer materials by electrical breakdown using atomic force microscopy

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Nanotechnology and Precision Engineering 2024年第1期7卷 71-77页

作者： Yajie Yang Jiajia Lu Yanbo Xie Libing duan School of Physical Science and Technology Northwestern Polytechnical UniversityXi’an 710072China School of Aeronautics and Institute of Extreme Mechanics Northwestern Polytechnical UniversityXi’an 710072China

The development of nanoelectronics and nanotechnologies has been boosted signiﬁcantly by the emergence of 2D materials because of their atomic thickness and peculiar properties,and developing a universal,precise patterning technology for single-layer 2D materials is critical for assembling *** here is a nanomachining technique using electrical breakdown by an AFM tip to fabricate nanopores,nanostrips,and other nanostructures on *** can be achieved by voltage scanning or applying a constant voltage while moving the *** measuring the electrical current,the formation process on single-layer materials was shown *** present results provide evidence of successful pattern fabrication on single-layer MoS2,boron nitride,and graphene,although further conﬁrmation is still *** proposed method holds promise as a general nanomachining technology for the future.

关键词： 2D material Nanopattern AFM Electrical breakdown Lithography

A Novel Multi-Stream Fusion Network for Underwater Image Enhancement

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China Communications 2024年第2期21卷 166-182页

作者： Guijin Tang Lian duan Haitao Zhao Feng Liu Jiangsu Key Laboratory of Image Processing and Image Communication Nanjing University of Posts and TelecommunicationsNanjing 210003China Jiangsu Key Laboratory of Wireless Communications Nanjing University of Posts and TelecommunicationsNanjing 210003China

Due to the selective absorption of light and the existence of a large number of floating media in sea water, underwater images often suffer from color casts and detail blurs. It is therefore necessary to perform color correction and detail restoration. However,the existing enhancement algorithms cannot achieve the desired results. In order to solve the above problems, this paper proposes a multi-stream feature fusion network. First, an underwater image is preprocessed to obtain potential information from the illumination stream, color stream and structure stream by histogram equalization with contrast limitation, gamma correction and white balance, respectively. Next, these three streams and the original raw stream are sent to the residual blocks to extract the features. The features will be subsequently fused. It can enhance feature representation in underwater images. In the meantime, a composite loss function including three terms is used to ensure the quality of the enhanced image from the three aspects of color balance, structure preservation and image smoothness. Therefore, the enhanced image is more in line with human visual ***, the effectiveness of the proposed method is verified by comparison experiments with many stateof-the-art underwater image enhancement algorithms. Experimental results show that the proposed method provides superior results over them in terms of MSE,PSNR, SSIM, UIQM and UCIQE, and the enhanced images are more similar to their ground truth images.

关键词： image enhancement multi-stream fusion underwater image

Automated Vulnerability Detection of Blockchain Smart Contacts Based on BERT Artificial Intelligent Model

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China Communications 2024年第7期21卷 237-251页

作者： Feng Yiting Ma Zhaofeng duan Pengfei Luo Shoushan School of Cyberspace Security Beijing University of Posts and TelecommunicationsBeijing 100876China

The widespread adoption of blockchain technology has led to the exploration of its numerous applications in various *** algorithms and smart contracts are critical components of blockchain *** the benefits of virtual currency,vulnerabilities in smart contracts have resulted in substantial losses to *** researchers have identified these vulnerabilities and developed tools for detecting them,the accuracy of these tools is still far from satisfactory,with high false positive and false negative *** this paper,we propose a new method for detecting vulnerabilities in smart contracts using the BERT pre-training model,which can quickly and effectively process and detect smart *** specifically,we preprocess and make symbol substitution in the contract,which can make the pre-training model better obtain contract *** evaluate our method on four datasets and compare its performance with other deep learning models and vulnerability detection tools,demonstrating its superior accuracy.

关键词： BERT blockchain smart contract vulnerability detection

PEGA:probabilistic environmental gradient-driven genetic algorithm considering epigenetic traits to balance global and local optimizations

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Frontiers of Information Technology & Electronic Engineering 2024年第6期25卷 839-855页

作者： Zhiyu duan Shunkun YANG Qi SHAO Minghao YANG School of Reliability and Systems Engineering Beihang UniversityBeijing 100191China

Epigenetics’flexibility in terms of finer manipulation of genes renders unprecedented levels of refined and diverse evolutionary mechanisms *** the epigenetic perspective,the main limitations to improving the stability and accuracy of genetic algorithms are as follows:(1)the unchangeable nature of the external environment,which leads to excessive disorders in the changed phenotype after mutation and crossover;(2)the premature convergence due to the limited types of epigenetic *** this paper,a probabilistic environmental gradientdriven genetic algorithm(PEGA)considering epigenetic traits is *** enhance the local convergence efficiency and acquire stable local search,a probabilistic environmental gradient(PEG)descent strategy together with a multi-dimensional heterogeneous exponential environmental vector tendentiously generates more offsprings along the gradient in the solution ***,to balance exploration and exploitation at different evolutionary stages,a variable nucleosome reorganization(VNR)operator is realized by dynamically adjusting the number of genes involved in mutation and *** on the above-mentioned operators,three epigenetic operators are further introduced to weaken the possible premature problem by enriching genetic *** experimental results on the open Congress on Evolutionary Computation-2017(CEC’17)benchmark over 10-,30-,50-,and 100-dimensional tests indicate that the proposed method outperforms 10 state-of-the-art evolutionary and swarm algorithms in terms of accuracy and stability on comprehensive *** ablation analysis demonstrates that for accuracy and stability,the fusion strategy of PEG and VNR are effective on 96.55%of the test functions and can improve the indicators by up to four orders of ***,the performance of PEGA on the real-world spacecraft trajectory optimization problem is the best in terms of quality of the solution.

关键词： Evolutionary algorithm Epigenetics Epigenetic algorithm Probabilistic environmental vector Variable nucleosome reorganization

Influences of chemical reactions on polysulfide reduction reaction process on promotor surface in Li-S batteries

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Nano Research 2024年第4期17卷 2712-2718页

作者： Yufeng Luo Zhenhan Fang Zixin Hong Shaorong duan Haitao Liu Hengcai Wu Qunqing Li Yuegang Zhang Shoushan Fan Wenhui duan Jiaping Wang Tsinghua-Foxconn Nanotechnology Research Center Tsinghua UniversityBeijing 100084China Department of Physics Tsinghua UniversityBeijing 100084China Laboratory of Computational Physics Institute of Applied Physics and Computational MathematicsBeijing 100088China Frontier Science Center for Quantum Information Tsinghua UniversityBeijing 100084China

Polar promotors have been proven effective in catalyzing the polysulfide(PS)reduction reaction(PSRR)process in lithium-sulfur(Li-S)***,the promotor surface tends to be poisoned due to the accumulation of insoluble discharging products of lithium disulfide(Li_(2)S_(2))and lithium sulfide(Li_(2)S)during Li-S battery ***,we investigate the detailed PSRR mechanism on the surface of manganese sulfides(MnS)as a representative promoter by performing in-situ Raman mapping *** catalytic ability of MnS enables thorough electrochemical reduction of PSs to Li_(2)S_(2) and Li_(2)S on the MnS *** generated Li_(2)S_(2) and Li_(2)S then adsorb the dissolved PSs via chemical reactions among sulfur species during the subsequent PSRR *** phenomenon mitigates promotor poisoning and continuously improves the reversible ***,the assembled Li-S cell demonstrates excellent electrochemical performance after introducing a conductive interlayer containing a thin piece of carbon nanotube film and MnS promotors.

关键词： promotors polysulfides chemical reactions catalytic ability in-situ Raman measurements

Optimal confrontation position selecting games model and its application to one-on-one air combat

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Defence Technology（防务技术） 2024年第1期31卷 417-428页

作者： Zekun duan Genjiu Xu Xin Liu Jiayuan Ma Liying Wang School of Mathematics and Statistics Northwestern Polytechnical UniversityXi'an 710072China International Joint Research Center on Operations Research Optimization and Artificial IntelligenceXi'an 710129China AVIC Xi’an Aeronautics Computing Technique Research Institute Xi'an 710065China Unmanned System Research Institute Northwestern Polytechnical UniversityXi'an 710072China

In the air combat process,confrontation position is the critical factor to determine the confrontation situation,attack effect and escape probability of ***,selecting the optimal confrontation position becomes the primary goal of maneuver *** taking the position as the UAV’s maneuver strategy,this paper constructs the optimal confrontation position selecting games(OCPSGs)*** the OCPSGs model,the payoff function of each UAV is defined by the difference between the comprehensive advantages of both sides,and the strategy space of each UAV at every step is defined by its accessible space determined by the *** we design the limit approximation of mixed strategy Nash equilibrium(LAMSNQ)algorithm,which provides a method to determine the optimal probability distribution of positions in the strategy *** the simulation phase,we assume the motions on three directions are independent and the strategy space is a cuboid to simplify the *** simulations are performed to verify the feasibility,effectiveness and stability of the algorithm.

关键词： Unmanned aerial vehicles(UAVs) Air combat Continuous strategy space Mixed strategy Nash equilibrium

Multiplayer Reach-Avoid Differential Games in 3D Space Inspired by Harris'Hawks'Cooperative Hunting Tactics

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Research 2024年第2期2023卷 41-54页

作者： Wanying Ruan Haibin duan Yongbin Sun Wanmai Yuan Jie Xia State Key Laboratory of Virtual Reality Technology and Systems School of Automation Science and Electrical EngineeringBeihang UniversityBeijingChina Peng Cheng Laboratory ShenzhenChina Information Science Academy of CETC BeijingChina

This paper investigates a multiplayer reach-avoid differential game in 3-dimensional(3D)space,which involves multiple pursuers,multiple evaders,and a designated target *** evaders aim to reach the target region,while the pursuers attempt to guard the target region by capturing the *** class of research holds significant practical ***,the complexity of the problem escalates substantially with the growing number of players,rendering its solution extremely *** this paper,the multiplayer game is divided into many subgames considering the cooperation among pursuers,reducing the computational burden,and obtaining numerically tractable strategies for ***,the Apollonius sphere,a fundamental geometric tool for analyzing the 3D differential game,is formulated,and its properties are *** on this,the optimal interception point for the pursuer to capture the evader is derived and the winning conditions for the pursuer and evader are ***,based on the Apollonius sphere,the optimal state feedback strategies of players are designed,and simultaneously,the optimal one-to-one pairings are ***,the Value function of the multiplayer reach-avoid differential game is explicitly given and is proved to satisfy Hamilton-Jacobi-Isaacs(HJI)***,the matching algorithm for the case with pursuers outnumbered evaders is provided through constructing a weighted bipartite graph,and the cooperative tactics for multiple pursuers are proposed,inspired by the Harris'Hawks intelligent cooperative hunting ***,numerical simulations are conducted to illustrate the effectiveness of the theoretical results for both cases where the number of adversary players is equal and unequal between the 2 groups.

关键词： holds satisfy rendering