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Key technologies of earthquake early warning system for China’s high-speed railway
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作者 Geming Zhang Lin Yang Wenxiang Jiang 《Railway Sciences》 2024年第2期239-262,共24页
Purpose–The purpose of this study is to introduce the top-level design ideas and the overall architecture of earthquake early-warning system for high speed railways in China,which is based on P-wave earthquake early-... Purpose–The purpose of this study is to introduce the top-level design ideas and the overall architecture of earthquake early-warning system for high speed railways in China,which is based on P-wave earthquake early-warning and multiple ways of rapid treatment.Design/methodology/approach–The paper describes the key technologies that are involved in the development of the system,such as P-wave identification and earthquake early-warning,multi-source seismic information fusion and earthquake emergency treatment technologies.The paper also presents the test results of the system,which show that it has complete functions and its major performance indicators meet the design requirements.Findings–The study demonstrates that the high speed railways earthquake early-warning system serves as an important technical tool for high speed railways to cope with the threat of earthquake to the operation safety.The key technical indicators of the system have excellent performance:The first report time of the P-wave is less than three seconds.From the first arrival of P-wave to the beginning of train braking,the total delay of onboard emergency treatment is 3.63 seconds under 95%probability.The average total delay for power failures triggered by substations is 3.3 seconds.Originality/value–The paper provides a valuable reference for the research and development of earthquake early-warning system for high speed railways in other countries and regions.It also contributes to the earthquake prevention and disaster reduction efforts. 展开更多
关键词 Earthquake early-warning high speed railway China earthquake networks center(CENC) Earthquake emergency treatment
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Sealed model and computation of hazardous waste landfill high voltage DC leakage detection
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作者 杨萍 Tian Jinwen +1 位作者 Wang Yanni Xue Lin 《High Technology Letters》 EI CAS 2015年第4期457-464,共8页
According to the structural characteristics of hazardous waste landfill and the leakage current model of high voltage DC Landfill leakage detection, a sealed model is established detail. The detection layer of the haz... According to the structural characteristics of hazardous waste landfill and the leakage current model of high voltage DC Landfill leakage detection, a sealed model is established detail. The detection layer of the hazardous waste landfill is considered as a sealed assumed that the source current flows through the leak entirely. The leak is regard and analyzed in space and it is ed as a positive current resource + I located at the current entrance or a negative resource - I located at the current exit, which depends on the placement of the current supply. The electrical potential of an arbitrary in detection layer satisfies Poisson equation. The boundary condition is regarded as a natural bound- ary condition for the high resistivity of high density polyethylene (HDPE) membrane. Based on which a numerical calculation method is developed. Satisfactory agreement between experimental da- ta and simulated data validates the analysis. Parametric studies show that a larger horizontal distance between the power supply electrode and leak and a smaller distance between the detector electrodes and the detected liner are helpful to leak location. More parametric curves show that parameters leaks can be detected effectively with optimum selection of field survey. 展开更多
关键词 hazardous waste landfill high voltage DC method sealed space model
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Highly Hazardous Pesticides (HHPs) Registered andTheir Use in Sub-Saharan Africa
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作者 Ngamo Tinkeu Léonard Simon Ngatanko Iliassa +5 位作者 Tamgno Béranger Raoul Watching Djakissam Madou Chantal Ayiki Evele Nathanael Goudoum Augustin Ngassoum Martin-Bénoit 《Journal of Agricultural Science and Technology(A)》 2019年第6期344-350,共7页
To sustain agricultural production,pesticides are highly recommanded.In sub-Saharan Africa,two regulatory bodies are in charge of pesticide registration,for more than 10 years of duty,the impact of their activity has ... To sustain agricultural production,pesticides are highly recommanded.In sub-Saharan Africa,two regulatory bodies are in charge of pesticide registration,for more than 10 years of duty,the impact of their activity has not yet best carried out.The present investigation aimed to evaluate the evolution in the quality of pesticides in agriculture in sub-Saharan Africa.Registration of pesticides began in Cameroon in 1996.There,less than 5%of pesticides used in 2004 were registered and more than 80%of producers were not aware of this legal process.In 2014,85%of pesticides used are registered.In sub-Saharan Africa,Highly Hazardous Pesticides(HHPs)registered are rondenticides,insecticides and nematocides.They are frequently used for the protection of stored products.Ilicit Persistent Organic Pollutants(POPs)(heptachlore,chlorobenzene)and HHP(alluminium phosphide,terbufos,abamectine,ethropophos,etc.)are frequently used to protect stored grains.And 40%are registered for use in intensive bananas production(28%for nematodes control alone and 10%for control of both insects and nematodes).Moreover,20%of HHPs registered are for the control of rondents. 展开更多
关键词 Sub-Saharan Africa chemical pest control highly hazardous pesticides alternatives
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Analysis of the Risk of Water Breakout in the Bottom Plate of High-Intensity Mining of Extra-Thick Coal Seams
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作者 Shuo Wang Hongdong Kang Xinchen Wang 《Journal of Geoscience and Environment Protection》 2024年第5期81-91,共11页
In order to clarify the danger of water breakout in the bottom plate of extra-thick coal seam mining, 2202 working face of a mine in the west is taken as the research object, and it is proposed to use the on-site moni... In order to clarify the danger of water breakout in the bottom plate of extra-thick coal seam mining, 2202 working face of a mine in the west is taken as the research object, and it is proposed to use the on-site monitoring means combining borehole peeping and microseismic monitoring, combined with the theoretical analysis to analyze the danger of water breakout in the bottom plate. The results show that: 1) the theoretically calculated maximum damage depth of the bottom plate is 27.5 m, and its layer is located above the Austrian ash aquifer, which has the danger of water breakout;2) the drill hole peeping at the bottom plate of the working face shows that the depth of the bottom plate fissure development reaches 26 m, and the integrity of the water barrier layer has been damaged, so there is the risk of water breakout;3) for the microseismic monitoring of the anomalous area, the bottom plate of the return air downstream channel occurs in the field with a one-week lag, which shows that microseismic monitoring events may reflect the water breakout of the underground. This shows that the microseismic monitoring events can reflect the changes of the underground flow field, which can provide a reference basis for the early warning of water breakout. The research results can provide reference for the prediction of sudden water hazard. 展开更多
关键词 Extra-Thick Coal Seam high-Intensity Mining Microseismic Monitoring Water-Surge hazard Borehole Peeping
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Effect of variety and seed dressing on emergence of high-oleic peanut under low temperature and high soil humidity conditions 被引量:1
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作者 Chuantang Wang Zhiwei Wang +4 位作者 Ying Wei Yueyi Tang Feifei Wang Hongwei Han Yan Sun 《Oil Crop Science》 CSCD 2021年第4期164-168,共5页
Low temperature coupled with high soil moisture during sowing to emergence generally results in poor peanut stand,thereby posing a non-negligible threat to peanut production in north and northeast China.Five high-olei... Low temperature coupled with high soil moisture during sowing to emergence generally results in poor peanut stand,thereby posing a non-negligible threat to peanut production in north and northeast China.Five high-oleic(HO)peanut cultivars and 4 seed dressing treatments capable of controlling several diseases and insect pests along with untreated checks were used to find the best combinations to cope with the dual stresses during sowing to emergence period.High broad-sense hereditability estimates of seedling emergence indicated great potential for genetic improvement of this trait.Analysis of variance in the split-plot experiment showed that the main effects of variety and seed dressing and their interaction on seedling emergence were significant.Seed dressing treatments increased seedling emergence percentage by 2.09–35.00 percent points.Four of the 5 HO peanut cultivars yielded satisfactory results.For Huayu 665,Huayu 668 and Huayu 965,Huweisanbao may be the best option;for Huayu 962,Weilidan was highly acceptable.These combinations will be evaluated further in multiple environments before large-scale extension. 展开更多
关键词 GROUNDNUT high oleate Seed-coating Split-plot design emergence percentage Chill stress high soil moisture
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Multi-hazard performance assessment of a transfer-plate high-rise building 被引量:2
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作者 Xiangming Zhou 徐幼麟 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2007年第4期371-382,共12页
Many urban areas are located in regions of moderate seismicity and are subjected to strong wind. Buildings in these regions are often designed without seismic provisions. As a result, in the event of an earthquake, th... Many urban areas are located in regions of moderate seismicity and are subjected to strong wind. Buildings in these regions are often designed without seismic provisions. As a result, in the event of an earthquake, the potential for damage and loss of lives may not be known. In this paper, the performance of a typical high-rise building with a thick transfer plate (TP), which is one type of building structure commonly found in Hong Kong, is assessed against both earthquake and wind hazards. Seismic- and wind-resistant performance objectives are first reviewed based on relevant codes and design guidelines for high-rise buildings. After a brief introduction of wind-resistant design of the building, various methodologies, including equivalent static load analysis (ESLA), response spectrum analysis (RSA), pushover analysis (POA), linear and nonlinear time-history analysis (LTHA and NTHA), are employed to assess the seismic performance of the building when subjected to frequent earthquakes, design based earthquakes and maximum credible earthquakes. The effects of design wind and seismic action with a common 50-year return period are also compared. The results indicate that most performance objectives can be satisfied by the building, but there are some objectives, such as inter-story drift ratio, that cannot be achieved when subjected to the frequent earthquakes. It is concluded that in addition to wind, seismic action may need to be explicitly considered in the design of buildings in regions of moderate seismicity. 展开更多
关键词 multi-hazard performance-based design SEISMIC moderate seismicity WIND pushover analysis transferplate high-rise building
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Relationships between Potential Risk of Hazardous Material Releases and Socio-Economic Demographic Characteristics Using Geospatial Analysis
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作者 Seong Nam Hwang Venu Srivastav Kannegalla 《Journal of Geoscience and Environment Protection》 2021年第7期62-85,共24页
The problem investigated in this research is about the potential risk of technological hazards, which poses a perilous threat to humankind and the environment. Rapid urbanization has been increasing the population den... The problem investigated in this research is about the potential risk of technological hazards, which poses a perilous threat to humankind and the environment. Rapid urbanization has been increasing the population density in an area, elevating the risk of exposure to technological disasters. Therefore, it is necessary to detect the areas with higher chemical risk to spread awareness about the potential risk zones and reduce actual damage and casualties resulting from the hazardous substance events. The basic design of the study utilizes geospatial analysis to map the TRI (Toxics Release Inventory) facilities in the communities of Texas to establish a relationship between potential </span><span style="font-family:Verdana;">hazardous material release zones and the human population at risk. The</span><span style="font-family:Verdana;"> study identified the vulnerable counties as well as investigated how those risk areas are related to race/ethnicity, income and education. The research would contribute to the policymakers acting on the hazard situation and keep them better prepared for</span><span style="color:red;"> </span><span style="font-family:Verdana;">chemical hazards. In addition, it would help the residents and emergency managers to better understand the circumstance to mitigate the consequences as well as increase their awareness to be ready for the uncertainties in the hotspots involved in high risk of the hazards. 展开更多
关键词 Environmental hazard Risk GIS DISASTER hazard Mitigation emergency Management Toxics Release Inventory (TRI) Facilities and Socioeconomic Demographic Characteristics
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Classification,Hazards and Countermeasures of Agricultural Environmental Pollution Emergencies
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作者 Xiaoming CHUAI Haixia ZHOU +2 位作者 Jianping ZHAO Shubo CHENG Jiang YU 《Asian Agricultural Research》 2013年第9期78-80,共3页
Agricultural environmental pollution emergencies have become a hot research topic because of the high incidence and influence depth.This paper introduces classification and features of agricultural environmental pollu... Agricultural environmental pollution emergencies have become a hot research topic because of the high incidence and influence depth.This paper introduces classification and features of agricultural environmental pollution emergencies:by pollutant type,it falls into organic pollution emergencies and inorganic pollution emergencies;by the approach of entering agricultural environment,it falls into water resource agricultural environmental pollution emergencies and non-water resource agricultural environmental pollution emergencies.Hazards of agricultural environmental pollution emergencies are analyzed from 4 perspectives:personal security,indirect loss,ecological environment and social stability.In view of the hazards,countermeasures are given to deal with the pollution emergencies as(i)establishing a risk evaluation mechanism for agricultural environment;(ii)enhancing the capacity of handling agricultural environmental pollution emergencies;(iii)introducing new management concepts for environmental emergencies,and cultivating keen emergency management consciousness. 展开更多
关键词 AGRICULTURE Environmental POLLUTION emergENCY CLAS
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Research Progress on the Occupational Hazards and Protective Measures of Emergency Department Nurses
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作者 Dongyun Chen Bing Lv Rongyan Liu 《Journal of Clinical and Nursing Research》 2022年第2期134-138,共5页
The emergency department is a department that is crucial for medical institutions.It is mainly responsible for rescuing critically ill patients and dealing with all kinds of public health emergencies.There are signifi... The emergency department is a department that is crucial for medical institutions.It is mainly responsible for rescuing critically ill patients and dealing with all kinds of public health emergencies.There are significant differences in the working environment and working mode between the nurses in emergency departments and those of other departments.They tend to come into contact with various occupational risk factors,resulting in high incidence of occupational hazards and accidental injuries.Therefore,it is necessary to analyze the common occupational risk factors of nurses in the emergency department and propose protective measures to ensure that these nurses are able to provide nursing services safely and effectively. 展开更多
关键词 emergency department NURSE Occupational hazards PROTECT
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Simulation Modeling on Emergency Evacuation in High-Speed Railway Stations in China
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作者 MA Qing-yuan WANG Chen LU Jian 《Journal of Donghua University(English Edition)》 EI CAS 2016年第6期836-842,共7页
A simulation study on occupant evacuation in high-speed railway stations (HSRSs) was presented in China. Pathfinder was employed as the simulation platform and a typical HSRS in a medinm-sized city in China was sele... A simulation study on occupant evacuation in high-speed railway stations (HSRSs) was presented in China. Pathfinder was employed as the simulation platform and a typical HSRS in a medinm-sized city in China was selected for model development. The model was carefully calibrated and validated by comparing simulation results with field data. Evacuation efficiency could be improved with the increased door width while such effect decreased when the door width reached a marginal value. And the marginal value varied under different occupant densities. An exponential function between evacuation lime and occupant density was fitted, indicating that occupant density significantly affected evacuation efficiency. A set of different evacuation strategies were compared, in terms of their evacuation performances. It was found that a balanced door usage would result in more efficient evacuations in HSRSs. Thus occupant flows were suggested to be managed considering door capacity. To avoid potential safety issues caused by such strategy ( e. g. , more occupants could be evacuated from a smaller area designed with higher door capacity ), occupants needed to enhance their awareness of following evacuation guidance instead of panic escape in emergencies. Moreover, such safety issues could also be avoided during the design phase that the evacuation capacity was designed to be proportional to the room capacity for each floor. The results of this study provide valuable information for HSRS design and flow management in China. 展开更多
关键词 simulation modeling emergency evacuation high-speed railway stations(HSRSs) evacuation time
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“四链”深度融合下战略性新兴产业高质量发展战略研究 被引量:6
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作者 王海南 王礼恒 +5 位作者 周志成 王国庆 王崑声 王红 朱钰婷 姜彬 《中国工程科学》 CSCD 北大核心 2024年第1期1-12,共12页
推动创新链、产业链、资金链、人才链深度融合,提升产业创新能力是我国战略性新兴产业迈向全球产业链中高端,实现高质量发展的关键。本文通过系统分析战略性新兴产业高质量发展的本质要求及内涵特征,研判全球战略性新兴产业发展格局变... 推动创新链、产业链、资金链、人才链深度融合,提升产业创新能力是我国战略性新兴产业迈向全球产业链中高端,实现高质量发展的关键。本文通过系统分析战略性新兴产业高质量发展的本质要求及内涵特征,研判全球战略性新兴产业发展格局变化及趋势,分析我国战略性新兴产业发展现状、问题及挑战,提出“创新驱动、企业主体、开放融合”的战略性新兴产业高质量发展思路和“体系融合、协同发展,自主可控、开放创新,企业主体、市场机制,前瞻布局、高端引领”的发展原则,研究提出各领域重点发展方向及“系统性提升、融合式创新、市场化推动、引领性发展”的发展策略,以期为战略性新兴产业高质量发展提供参考。 展开更多
关键词 “四链”融合 融合集群 战略性新兴产业 高质量发展
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基于四“新”维度的新质生产力发展路径研究 被引量:6
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作者 齐文浩 赵晨 苏治 《兰州大学学报(社会科学版)》 北大核心 2024年第2期15-24,共10页
新质生产力的发展是推动我国经济转型,实现高质量发展的关键。基于四“新”维度,新质生产力相较于传统生产力是依靠技术突破创新而产生的生产力跃迁,是以新劳动者、新劳动对象、新劳动工具和新基础设施为核心的生产力。新质生产力依靠... 新质生产力的发展是推动我国经济转型,实现高质量发展的关键。基于四“新”维度,新质生产力相较于传统生产力是依靠技术突破创新而产生的生产力跃迁,是以新劳动者、新劳动对象、新劳动工具和新基础设施为核心的生产力。新质生产力依靠科技推动的本质没有发生变化,但其依靠持续的技术突破,摆脱了资源驱动型的传统发展模式,带来的是更清洁、更高效的环境友好型发展模式。随着我国科技创新能力持续增强、新兴产业不断发展壮大、能源转型和新型基础设施建设的不断加快,我国新质生产力发展条件呈现出逐年向好的态势,但也存在新劳动者储备不足、新劳动工具发展受限、新劳动对象应用场景欠缺、新型基础设施协调性较差等问题。新质生产力的发展一是要着重培养新科技人才、数字技术人才和“卡脖子”关键技术人才;二是要以基础研究为依托,推动整体科技创新能力提升,以实现真正的技术突破;三是要尽快建立起数据大市场;四是要以需求为导向推动新型基础设施建设,强调建用并重,强化以用促建。 展开更多
关键词 新质生产力 经济高质量发展 科技推动 新兴产业 未来产业
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基于PHA-LEC-SCL法高校实验室安全评价体系的研究 被引量:1
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作者 刘音 闵令冉 张升堂 《当代化工研究》 CAS 2024年第2期144-146,共3页
随着高校科研项目的增加,人员的流动性增强,安全事故也随之增加。通过对高校实验室安全管理工作的总结与分析,探讨了影响实验室安全的各种因素,运用预先危险性分析法(PHA),对高校实验室的危险有害因素进行识别和定性分析,并将作业条件... 随着高校科研项目的增加,人员的流动性增强,安全事故也随之增加。通过对高校实验室安全管理工作的总结与分析,探讨了影响实验室安全的各种因素,运用预先危险性分析法(PHA),对高校实验室的危险有害因素进行识别和定性分析,并将作业条件危险性评价法(LEC)与之相结合,对各子系统进行风险评估,并对其风险程度进行定量计算。采用安全检查表(SCL)对高校实验室进行安全综合评价,建立了安全评价方法之间的内在联系,从而定性定量的判定高校实验室安全等级,以便及时对危险有害因素做出反应,防止事故的发生。 展开更多
关键词 高校实验室 预先危险性分析 作业条件危险性评价 安全检查表 安全评价
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以高水平急诊大平台建设推动急诊创伤医学的高质量发展 被引量:1
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作者 白祥军 杨帆 《创伤外科杂志》 2024年第1期1-5,共5页
我国现代急诊医学起步虽晚,但近年来发展较快。在急诊3.0时代,急诊科的核心价值观是以需求、问题、危重度、“时间线”和“时间窗”为导向,以学科建设为中心,以“五大中心”为抓手构建院前院内一体化高水平急诊大平台。努力整合高水平... 我国现代急诊医学起步虽晚,但近年来发展较快。在急诊3.0时代,急诊科的核心价值观是以需求、问题、危重度、“时间线”和“时间窗”为导向,以学科建设为中心,以“五大中心”为抓手构建院前院内一体化高水平急诊大平台。努力整合高水平救治平台、高水平技术能力、高素质人才队伍、高层次人才培养能力、高水平管理能力和高效率运行能力,进一步推动急诊创伤医学和公立医院的高质量发展,更好地满足人民日益增长的急诊医疗卫生服务需求。 展开更多
关键词 急诊外科 创伤外科 创伤中心 高质量发展
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潜艇高压气吹除主压载水舱应急挽回的运动规律和控制策略
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作者 刘辉 李志辉 +1 位作者 官东 吴向君 《海军工程大学学报》 CAS 北大核心 2024年第1期29-33,共5页
针对潜艇高压气吹除压载水舱应急挽回姿态控制难题,以吹除高压气和压载水舱中压力气体为研究对象,推导并构建了高压气吹除和压载水舱解除气压数理模型。结合潜艇应急挽回数学模型,对潜艇发生破损进水事故的应急挽回过程进行数值仿真,分... 针对潜艇高压气吹除压载水舱应急挽回姿态控制难题,以吹除高压气和压载水舱中压力气体为研究对象,推导并构建了高压气吹除和压载水舱解除气压数理模型。结合潜艇应急挽回数学模型,对潜艇发生破损进水事故的应急挽回过程进行数值仿真,分析了某潜艇事故采取3种不同挽回方案条件下潜艇运动姿态变化规律。研究结果表明:所构建的数理模型能较好描述潜艇应急挽回姿态变化规律,为潜艇应急挽回运动规律预报、潜艇运动状态实时评估和姿态控制方案制定提供理论依据和技术支持。 展开更多
关键词 高压气 压载水舱 应急挽回
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海拔对隧道救援站列车火灾烟气蔓延特性的影响
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作者 周丹 张则栋 +2 位作者 陈涛 李金柱 陈光 《中南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第4期1602-1617,共16页
采用三维非定常N-S方程和完全浮力修正的RNG k-ε湍流模型,基于滑移网格技术实现列车在隧道内的运动过程模拟,构建高海拔隧道紧急救援站列车火灾数值模拟方法,并利用现有动模型试验和隧道静止火灾试验数据验证数值模拟方法的可靠性和正... 采用三维非定常N-S方程和完全浮力修正的RNG k-ε湍流模型,基于滑移网格技术实现列车在隧道内的运动过程模拟,构建高海拔隧道紧急救援站列车火灾数值模拟方法,并利用现有动模型试验和隧道静止火灾试验数据验证数值模拟方法的可靠性和正确性,研究海拔对事故隧道、紧急救援站和列车中部车厢附近横通道内的烟气流速和温度分布的影响规律。研究结果表明:当着火列车驶入隧道紧急救援站时,活塞风主导了火灾烟气的蔓延趋势;在列车停车瞬间,随着海拔增大,事故隧道拱顶处和列车中部车厢附近横通道拱顶处的烟气流速峰值及温度峰值逐渐增大;列车停车后,活塞风逐渐衰减,烟气开始在隧道拱顶处向火源上游逆流;随着海拔增大,紧急救援站下游高温区域蔓延范围逐渐扩大,事故隧道拱顶处温度峰值随之升高;随着时间推移,高海拔与低海拔隧道拱顶处的温度峰值差异逐渐增大,可能对更高海拔隧道救援站内的人员安全造成更大的威胁;不同海拔处列车中部车厢附近横通道内人眼高度处的温度均超过330 K(对人体有危害),且在同一时刻,海拔越高,横通道内高温烟气层高度越低,烟气沉降速度明显加快。 展开更多
关键词 高海拔 列车火灾 隧道紧急救援站 烟气蔓延
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泸定6.8级地震公路抢通保通方案
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作者 赵飞 朱明 +4 位作者 李杰 徐益飞 但晨 肖怡 邱瑞成 《土木与环境工程学报(中英文)》 CSCD 北大核心 2024年第3期216-226,共11页
2022年9月5日,四川泸定发生6.8级地震,公路沿线诱发了大量的地质灾害,造成多处公路损坏或断道,极大地影响了抗震救灾工作。快速摸清震区公路网的受损情况和抢通保通难度,对震后救援至关重要。为此,对震区公路受损情况进行调查,会同地方... 2022年9月5日,四川泸定发生6.8级地震,公路沿线诱发了大量的地质灾害,造成多处公路损坏或断道,极大地影响了抗震救灾工作。快速摸清震区公路网的受损情况和抢通保通难度,对震后救援至关重要。为此,对震区公路受损情况进行调查,会同地方交通部门完成公路的抢通保通任务。调查发现了507处受损点,公路灾害以崩塌滑坡为主,占总灾害的90%以上。公路灾害具有数量多、规模小、连片分布的特点,公路震害与地震烈度正相关,与断层距离、河流距离负相关。在不利因子组合下,公路震害程度明显加剧,局部位置的公路受损率可达到92.5%。在抢通保通阶段,利用龙头石及大岗山电站的库区水运资源,快速建立5处码头,建立起通往震中的生命通道,让应急队伍快速进入灾区,让伤员第一时间运送出来;灾后交通网的重建充分利用水运资源,不追求道路等级与路线指标,公路重建以提高公路的抗灾能力及韧性为目标。 展开更多
关键词 公路工程 泸定地震 同震灾害 抢通保通 公路受损率
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上木江坪高陡斜坡危岩特征与定量风险评估
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作者 凌斯祥 李乐 +6 位作者 石奥博 李晓宁 黄军朋 孙春卫 邓睿 赵思远 巫锡勇 《工程地质学报》 CSCD 北大核心 2024年第3期1083-1097,共15页
青藏高原东缘高陡斜坡危岩体严重威胁山区交通廊道的建设、运营与维护。本文以青藏高原东缘上木江坪高陡斜坡为研究对象,研究斜坡危岩体的崩塌落石对都四铁路和G350国道的危险性与定量风险,对山区交通廊道崩塌落石的防灾减灾具有重要意... 青藏高原东缘高陡斜坡危岩体严重威胁山区交通廊道的建设、运营与维护。本文以青藏高原东缘上木江坪高陡斜坡为研究对象,研究斜坡危岩体的崩塌落石对都四铁路和G350国道的危险性与定量风险,对山区交通廊道崩塌落石的防灾减灾具有重要意义。联合现场调查与无人机航空摄影技术,重建了高陡斜坡高精度三维地形,获取危岩体节理面产状,基于赤平投影明确了斜坡危岩体的破坏模式和稳定性。采用三维落石模拟软件RockyFor3D模拟了斜坡崩塌落石的运动轨迹,定量评估了落石危害范围、危险性分区与对道路车辆的定量风险。研究结果表明:斜坡后壁存在3处危岩体(A、B、C),分别且受3组节理控制,斜坡破坏为楔形破坏为主,斜坡危岩体处于基本稳定-不稳定状态。通过落石三维运动模拟可知,落石的运动轨迹受地形控制,在坡降较大位置,最大弹跳高度、最大速度与最大动能呈陡增趋势。危岩体A和B不会对都四铁路与G350国道产生威胁,仅使G350国道服务区西边和西南边缘处于极低危险区,其车辆风险均处于可接受风险区。危岩体C将使G350国道服务区、G350国道和都四铁路隧道口均处于极低-低危险区,对都四铁路和G350国道的车辆遇到落石的定量风险位于风险警告区,应对危岩体C的崩塌落石制定相应防灾减灾对策。 展开更多
关键词 高位岩崩 危岩特征 运动轨迹 落石危险性 风险评估
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高速-重载全地形车仿生悬架系统运动学分析
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作者 李占龙 万世永 +3 位作者 张正 任志曌 高山铁 刘志奇 《中国工程机械学报》 北大核心 2024年第1期13-18,共6页
全球自然灾害形势复杂,极端灾害事件呈频发、高发、突发态势。某型高速-重载全地形车作业过程中会产生剧烈振动,传统减振方案存在诸多影响减振效能的潜在因素。从仿生学原理和生物力学机理入手,探究自然界犀牛、袋鼠的生物缓冲特性与全... 全球自然灾害形势复杂,极端灾害事件呈频发、高发、突发态势。某型高速-重载全地形车作业过程中会产生剧烈振动,传统减振方案存在诸多影响减振效能的潜在因素。从仿生学原理和生物力学机理入手,探究自然界犀牛、袋鼠的生物缓冲特性与全地形车速度快、承载重、冲击强等应用性能之间的内在联系,结合机械原理,研究一套结构紧凑、抗冲击能力强的仿生悬架系统,响应高速-重载全地形车在复杂地形下应急保障工作的需求。结合几何原理建立仿生悬架系统运动学数学模型,求得各输入、输出角位置参数数值算例,并对三维模型展开位置仿真分析,验证数值算例的正确性。在验证其仿真结果与理论计算结果相符的基础上,对相应角速度及角加速度随时间变化的运动轨迹进行运动学分析,验证该机构在运动过程中的平稳性,表明结构设计符合减小冲击和振荡的实际运行需求。运动学数学模型可为后续结构参数优化、确定减振单元性能、进一步实行控制和试验工作提供可靠的数据资料和理论支撑,有助于提高减振系统研究与设计的效率,缩短研发周期,降低研究成本,同时为其他减振系统研究提供有益参考。 展开更多
关键词 高速-重载 应急保障工作 仿生学 悬架系统 运动学分析
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高海拔潮气量双环PID控制系统研究
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作者 王慧泉 魏志鹏 +1 位作者 马欣 邢海英 《电子测量技术》 北大核心 2024年第6期14-19,共6页
为解决高海拔地区气压降低导致急救呼吸机潮气量控制精度下降的问题,提出了双环PID潮气量控制系统。该系统采用气压补偿型PID控制器调整风机转速,并辅以积分分离式PID控制器,以实现对气流速度的精确控制。在实际海拔4370 m、大气压59 kP... 为解决高海拔地区气压降低导致急救呼吸机潮气量控制精度下降的问题,提出了双环PID潮气量控制系统。该系统采用气压补偿型PID控制器调整风机转速,并辅以积分分离式PID控制器,以实现对气流速度的精确控制。在实际海拔4370 m、大气压59 kPa的环境中,系统性能测试表明,相较于单环PID控制,双环控制系统在高海拔条件下表现出快速响应和无超调的卓越性能。平均气流速度输出误差为3.19%,最大误差为4.1%,优于现有临床设备的准确性。这一技术突破不仅提供了高海拔急救呼吸机潮气量控制的有效解决方案,也为特殊环境下的通气控制技术发展贡献了重要参考。 展开更多
关键词 高海拔地区 低气压 急救呼吸机 潮气量控制 气压补偿 双环PID
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