检索结果-南通市图书馆

Chinese Physics B 2024年第2期33卷 567-576页

作者：邓凯丰李梦胡祥敏陈涛 institute of public safety research Department of Engineering PhysicsTsinghua UniversityBeijing 100084China Anhui Province Key Laboratory of Human safety Hefei 230601China Beijing Key Laboratory of Comprehensive Emergency Response Science Beijing 100084China

An accurate assessment of the evacuation efficiency in case of disasters is of vital importance to the safety design of buildings and street blocks.Hazard sources not only physically but psychologically affect the pedestrians,which may further alter their behavioral patterns.This effect is especially significant in narrow spaces,such as corridors and alleys.This study aims to integrate a non-spreading hazard source into the social force model following the results from a previous experiment and simulation,and to simulate unidirectional pedestrian flows over various crowd densities and clarity–intensity properties of the hazard source.The integration include a virtual repulsion force from the hazard source and a decay on the social force term.The simulations reveal(i)that the hazard source creates virtual bottlenecks that suppress the flow,(ii)that the inter-pedestrian push forms a stabilisation phase on the flow-density curve within medium-to-high densities,and(iii)that the pedestrians are prone to a less orderly and stable pattern of movement in low clarity–intensity scenarios,possibly with lateral collisions passing the hazard source.

关键词： evacuation social force model hazard source unidirectional pedestrian flow

Semantic Consistency and Correctness Verification of Digital Traffic Rules

在线全文

学校读者我要写书评

暂无评论

Engineering 2024年第2期33卷 47-62页

作者： Lei Wan Changjun Wang Daxin Luo Hang Liu Sha Ma Weichao Hu Policy Standardand Patent DepartmentIntelligent Automotive Solution BUHuawei Technologies Co.Ltd.Beijing 100094China research institute for Road safety of the Ministry of public Security Beijing 100062China

The consensus of the automotive industry and traffic management authorities is that autonomous vehicles must follow the same traffic laws as human drivers.Using formal or digital methods,natural language traffic rules can be translated into machine language and used by autonomous vehicles.In this paper,a translation flow is designed.Beyond the translation,a deeper examination is required,because the semantics of natural languages are rich and complex,and frequently contain hidden assumptions.The issue of how to ensure that digital rules are accurate and consistent with the original intent of the traffic rules they represent is both significant and unresolved.In response,we propose a method of formal verification that combines equivalence verification with model checking.Reasonable and reassuring digital traffic rules can be obtained by utilizing the proposed traffic rule digitization flow and verification method.In addition,we offer a number of simulation applications that employ digital traffic rules to assess vehicle violations.The experimental findings indicate that our digital rules utilizing metric temporal logic(MTL)can be easily incorporated into simulation platforms and autonomous driving systems(ADS).

关键词： Autonomous driving Traffic rules Digitization Formalization Verification

Small-scale fire tests in the underwater tunnel section model with new sidewall smoke extraction

在线全文

学校读者我要写书评

暂无评论

Deep Underground Science and Engineering 2024年第2期3卷 247-254页

作者： Shunyu Yue Ruifeng Miao Huihang Cheng Maohua Zhong Xiujun Yang Department of Engineering Physics Institute of Public Safety ResearchTsinghua UniversityBeijingChina Shanxi Province Expressway Group Limited Liability Company Shanxi Expressway Group Shuoshen Co. LtdShuozhouChina research institute of Highway Ministry of Transport RIOH Transport ConsultantsLtdBeijingChina

The Shenzhen–Zhongshan Bridge is a 24‐km‐long bridge and tunnel system,including a 6.8-km-long super cross section subsea tunnel.To solve the smoke exhaust problem of a super large cross-section subsea tunnel,the tunnel has a new smoke exhaust system that combines a horizontal smoke exhaust cross section at the top and sidewall smoke exhaust holes.In order to evaluate the potential fire hazards of this type of tunnel,a 1:30 tunnel model was established and 140 smallscale experiments on underwater tunnel fires were conducted.By changing the fire power,fire location,and fan operation mode,different scenarios of submarine immersed tunnel fire were simulated and the related key parameters such as fire smoke diffusion behavior and smoke temperature distribution were studied.On this basis,the optimal smoke control strategy was proposed for different fire scenarios.The research results indicate that the new smoke exhaust system can fully utilize the smoke flow characteristics,significantly improve smoke exhaust efficiency,and increase available evacuation time,thus further enhancing the fire safety of super large cross-section subsea tunnels.

关键词： sidewall smoke extraction system small‐scale fire tests smoke control

维普期刊数据库博看期刊

Prevalence of Anemia in Patients with Diabetes Mellitus:A Systematic Review and Meta-Analysis

在线全文

学校读者我要写书评

暂无评论

Biomedical and Environmental Sciences 2024年第1期37卷 96-107页

作者： Monireh Faghir-Ganji Narjes Abdolmohammadi Maryam Nikbina Alireza Amanollahi Alireza Ansari-Moghaddam Rozhan Khezri Hamidreza Baradaran Student research Committee Iran University of Medical SciencesTehranIran Department of Epidemiology School of Public HealthIran University of Medical SciencesTehranIran Department of Epidemiology School of Public HealthTehran University of Medical SciencesTehranIran Department of Midwifery Shoushtar Faculty of Medical SciencesShoushtarIran Department of Epidemiology School of Public Health and SafetyShahid Beheshti University of Medical SciencesTehranIran Trauma and Injury research Center Iran University of Medical SciencesTehranIran Health Promotion research Center Zahedan University of Medical SciencesZahedanIran Endocrine research Center Institute of Endocrinology and MetabolismIran University of Medical SciencesTehranIran

Objective Anemia is a common public health concern in patients with type 2 diabetes worldwide.This study aimed to identify the prevalence of anemia among patients with diabetes.Methods Electronic databases,including PubMed,Scopus,Web of Sciences,and Google Scholar,were searched systematically for studies published between 2010 and 2021.After removing duplicates and inappropriate reports,the remaining manuscripts were reviewed and appraised using theNewcastleOttawa Scale(NOS)tool.A random-effects model was used to calculate the pooled estimates of the extracted data using Stata version 17.Heterogeneity of the studies was assessed using the Q statistic.Results A total of 51 articles containing information on 26,485 patients with diabetes were included in this study.The articles were mainly from Asia(58.82%)and Africa(35.29%).The overall prevalence of anemia was 35.45%(95%CI:30.30–40.76),with no evidence of heterogeneity by sex.Among the two continents with the highest number of studies,the prevalence of anemia in patients with diabetes was significantly higher in Asia[40.02;95%CI:32.72–47.54]compared to Africa[28.46;95%CI:21.90–35.50](P for heterogeneity=0.029).Moreover,there has been an increasing trend in the prevalence of anemia in patients with diabetes over time,from[15.28;95%CI:9.83–22.21]in 2012 to[40.70;95%CI:10.21–75.93]in 2022.Conclusion Globally,approximately 4 in 10 patients with diabetes suffer from anemia.Therefore,routine anemia screening and control programs every 3 months might be useful in improving the quality of life of these patients.

关键词： Prevalence Diabetic foot Anemia Diabetes mellitus

Lattice Boltzmann simulation study of anode degradation in solid oxide fuel cells during the initial aging process

在线全文

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2024年第2期31卷 405-411页

作者： Shixue Liu Zhijing Liu Shuxing Zhang Hao Wu Hydrogen Energy Industrial Technology Innovation Center China Nuclear Power Technology Research InstituteShenzhen 518031China Shenzhen Engineering research Center for Hydrogen safety Shenzhen 518031China

For present solid oxide fuel cells(SOFCs),rapid performance degradation is observed in the initial aging process,and the dis-cussion of the degradation mechanism necessitates quantitative analysis.Herein,focused ion beam-scanning electron microscopy was em-ployed to characterize and reconstruct the ceramic microstructures of SOFC anodes.The lattice Boltzmann method(LBM)simulation of multiphysical and electrochemical processes in the reconstructed models was performed.Two samples collected from industrial-size cells were characterized,including a reduced reference cell and a cell with an initial aging process.Statistical parameters of the reconstructed microstructures revealed a significant decrease in the active triple-phase boundary and Ni connectivity in the aged cell compared with the reference cell.The LBM simulation revealed that activity degradation is dominant compared with microstructural degradation during the initial aging process,and the electrochemical reactions spread to the support layer in the aged cell.The microstructural and activity de-gradations are attributed to Ni migration and coarsening.

关键词： solid oxide fuel cell anode degradation focused ion beam-scanning electron microscopy lattice Boltzmann method

Disentangling brain PrP^(C)proteoforms and their roles in physiology and disease

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration research 2024年第5期19卷 963-965页

作者： Ilaria Vanni Nonno Romolo Department of Food safety Nutrition and Veterinary Public HealthIstituto Superiore di SanitàRomeItaly

The cellular prion protein(PrPC),a cell surface glycoprotein of 209 amino acids,has been considerably studied over the decades mainly due to its critical involvement in transmissible spongiform encephalopathies,or prion diseases.Indeed,it is the misfolding and aggregation of PrPC into pathological assemblies-named PrPSc-that constitute prions,the agents causing these unusual neurodegenerative diseases affecting humans and animals(Prusiner,1982).Furthermore,increasing evidence support its relevance also in other neurodegenerative diseases(NDDs),such as Alzheimer’s and Parkinson’s diseases(Corbett et al.,2020).

关键词： diseases involvement glycoprotein

Patent-based technological developments and surfactants application of lithium-ion batteries fire-extinguishing agent

在线全文

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2024年第1期88卷 39-63,I0002页

作者： Jianqi Zhang Tao Fan Shuai Yuan Chongye Chang Kuo Wang Ziwei Song Xinming Qian State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100084China Industrial safety research institute China Academy of Safety Science and TechnologyBeijing 100012China Fire Engineering Department China People’s Police UniversityLangfang 065000HebeiChina

While newer,more efficient Lithium-ion batteries(LIBs)and extinguishing agents have been developed to reduce the occurrence of thermal runaway accidents,there is still a scarcity of research focused on the application of surfactants in different LIBs extinguishing agents,particularly in terms of patented technologies.The aim of this review paper is to provide an overview of the technological progress of LIBs and LIBs extinguishing agents in terms of patents in Korea,Japan,Europe,the United States,China,etc.The initial part of this review paper is sort out LIBs technology development in different regions.In addition,to compare LIBs extinguishing agent progress and challenges of liquid,solid,combination of multiple,and microencapsulated.The subsequent section of this review focuses on an in-depth analysis dedicated to the efficiency and challenges faced by the surfactants corresponding design principles of LIBs extinguishing agents,such as nonionic and anionic surfactants.A total of 451,760 LIBs-related patent and 20 LIBs-fire-extinguishing agent-related patent were included in the analyses.The extinguishing effect,cooling performance,and anti-recombustion on different agents have been highlighted.After a comprehensive comparison of these agents,this review suggests that temperature-sensitive hydrogel extinguishing agent is ideal for the effective control of LIBs fire.The progress and challenges of surfactants have been extensively examined,focusing on key factors such as surface activity,thermal stability,foaming properties,environmental friendliness,and electrical conductivity.Moreover,it is crucial to emphasize that the selection of a suitable surfactant must align with the extinguishing strategy of the extinguishing agent for optimal firefighting effectiveness.

关键词： LIBs Fire-extinguishing agent Surfactants Patent

Three-Dimensional Sound Source Location Algorithm for Subsea Leakage Using Hydrophone

在线全文

学校读者我要写书评

暂无评论

China Ocean Engineering 2024年第2期38卷 326-337页

作者： LI Hao-jie CAI Bao-ping YUAN Xiao-bing KONG Xiang-di LIU Yong-hong Javed Akbar KHAN CHU Zheng-de YANG Chao TANG An-bang College of Mechanical and Electronic Engineering China University of PetroleumQingdao 266580China Shenzhen Urban public safety Technology institute Shenzhen 518000China institute of Hydrocarbon Recovery Universiti Teknologi PETRONASBandar Seri IskandarPerak Darul Ridzuan 32610Malaysia

Leakages from subsea oil and gas equipment cause substantial economic losses and damage to marine ecosystem,so it is essential to locate the source of the leak.However,due to the complexity and variability of the marine environment,the signals collected by hydrophone contain a variety of noises,which makes it challenging to extract useful signals for localization.To solve this problem,a hydrophone denoising algorithm is proposed based on variational modal decomposition(VMD)with grey wolf optimization.First,the average envelope entropy is used as the fitness function of the grey wolf optimizer to find the optimal solution for the parameters K andα.Afterward,the VMD algorithm decomposes the original signal parameters to obtain the intrinsic mode functions(IMFs).Subsequently,the number of interrelationships between each IMF and the original signal was calculated,the threshold value was set,and the noise signal was removed to calculate the time difference using the valid signal obtained by reconstruction.Finally,the arrival time difference is used to locate the origin of the leak.The localization accuracy of the method in finding leaks is investigated experimentally by constructing a simulated leak test rig,and the effectiveness and feasibility of the method are verified.

关键词： grey wolf optimizer variational modal decomposition mean envelope entropy correlation coefficient time difference of arrival

SUPER WOMAN 2(SPW2)maintains organ identity in spikelets by inhibiting the expression of floral homeotic genes OsMADS3,OsMADS58,OsMADS13,and DROOPING LEAF

在线全文

学校读者我要写书评

暂无评论

Journal of Integrative Agriculture 2024年第1期23卷 59-76页

作者： Hui Zhuang Jinsong Lan Qiuni Yang Xiaoyu Zhao Yuhuan Li Jingya Zhi Yalin Shen GuanghuaHe Yunfeng Li Rice research institute Key Laboratory of Application and Safety Control of Genetically Modified CropsAcademy of Agricultural SciencesSouthwest UniversityChongqing 400715China

Flower organ identity in rice is mainly determined by the A-,B-,C-and E-class genes,with the majority encoding MADS-box transcription factors.However,few studies have investigated how the expression of these floral organ identity genes is regulated during flower development.In this study,we identified a gene named SUPER WOMAN 2(SPW2),which is necessary for spikelet/floret development in rice by participating in the regulation of the expression of pistil identity genes such as OsMADS3,OsMADS13,OsMADS58 and DL.In the spw2 mutant,ectopic stigma/ovary-like tissues were observed in the non-pistil organs,including sterile lemma,lemma,palea,lodicule,and stamen,suggesting that the identities of these organs were severely affected by mutations in SPW2.SPW2 was shown to encode a plant-specific EMF1-like protein that is involved in H3K27me3 modification as an important component of the PRC2 complex.Expression analysis showed that the SPW2 mutation led to the ectopic expression of OsMADS3,OsMADS13,OsMADS58,and DL in non-pistil organs of the spikelet.The ChIP-qPCR results showed significant reductions in the levels of H3K27me3 modification on the chromatin of these genes.Thus,we demonstrated that SPW2 can mediate the process of H3K27me3 modification of pistil-related genes to regulate their expression in non-pistil organs of spikelets in rice.The results of this study expand our understanding of the molecular mechanism by which SPW2 regulates floral organ identity genes through epigenetic regulation.

关键词： rice(Oryza sativa) spikelet organ identity H3K27me3

Predict the evolution of mechanical property of Al-Li alloys in a marine environment

在线全文

学校读者我要写书评

暂无评论

Defence Technology（防务技术） 2024年第1期31卷 557-566页

作者： Wei Li Lin Xiang Guang Wu Hongli Si Jinyan Chen Yiming Jin Yan Su Jianquan Tao Chunyang Huang State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100036China Chongqing Innovation Center Beijing Institute of TechnologyChongqing400044China First research institute of the Ministry of public Security for PR China Beijing100036China Southwest Technology and Engineering research institute Chongqing400039China

The ocean is one of the essential fields of national defense in the future,and more and more attention is paid to the lightweight research of Marine equipment and materials.This study it is to develop a Machine learning(ML)-based prediction method to study the evolution of the mechanical properties of Al-Li alloys in the marine environment.We obtained the mechanical properties of Al-Li alloy samples under uniaxial tensile deformation at different exposure times through Marine exposure experiments.We obtained the strain evolution by digital image correlation(DIC).The strain field images are voxelized using 2D-Convolutional Neural Networks(CNN)autoencoders as input data for Long Short-Term Memory(LSTM)neural networks.Then,the output data of LSTM neural networks combined with corrosion features were input into the Back Propagation(BP)neural network to predict the mechanical properties of Al-Li alloys.The main conclusions are as follows:1.The variation law of mechanical properties of2297-T8 in the Marine atmosphere is revealed.With the increase in outdoor exposure test time,the tensile elastic model of 2297-T8 changes slowly,within 10%,and the tensile yield stress changes significantly,with a maximum attenuation of 23.6%.2.The prediction model can predict the strain evolution and mechanical response simultaneously with an error of less than 5%.3.This study shows that a CNN/LSTM system based on machine learning can be built to capture the corrosion characteristics of Marine exposure experiments.The results show that the relationship between corrosion characteristics and mechanical response can be predicted without considering the microstructure evolution of metal materials.

关键词： Marine environment Al-Li alloy Machine learning Corrosion