Abstract： The containment vessel of a nuclear power plant is the last barrier to prevent nuclear reactor radiation. Aseismic safety analysis is the key to appropriate containment vessel design. A prestressed concrete...Abstract： The containment vessel of a nuclear power plant is the last barrier to prevent nuclear reactor radiation. Aseismic safety analysis is the key to appropriate containment vessel design. A prestressed concrete containment vessel （PCCV） model with a semi-infinite elastic foundation and practical arrangement of tendons has been established to analyze the aseismic ability of the CPR1000 PCCV structure under seismic loads and internal pressure. A method to model the prestressing tendon and its interaction with concrete was proposed and the axial force of the prestressing tendons showed that the simulation was reasonable and accurate. The numerical results show that for the concrete structure, the location of the cylinder wall bottom around the equipment hatch and near the ring beam are critical locations with large principal stress. The concrete cracks occurred at the bottom of the PCCV cylinder wall under the peak earthquake motion of 0.50 g, however the PCCV was still basically in an elastic state. Furthermore, the concrete cracks occurred around the equipment hatch under the design internal pressure of 0.4MPa, but the steel liner was still in the elastic stage and its leak-proof function soundness was verified. The results provide the basis for analysis and design of containment vessels.展开更多
This paper discusses some issues on human reliability model of time dependent human behavior. Some results of the crew reliability experiment on Tsinghua training simulator in China are given, Meanwhile, a case of ca...This paper discusses some issues on human reliability model of time dependent human behavior. Some results of the crew reliability experiment on Tsinghua training simulator in China are given, Meanwhile, a case of calculation for human error probability during anticipated transient without scram (ATWS) based on the data drew from the recent experiment is offered.展开更多
Stability analysis of strain-softening slopes is carried out using the shear strength reduction method and Mohr-Coulomb model with degrading cohesion and friction angle.The e ffect of strain-softening behavior on the ...Stability analysis of strain-softening slopes is carried out using the shear strength reduction method and Mohr-Coulomb model with degrading cohesion and friction angle.The e ffect of strain-softening behavior on the slope factor of safety is investigated by performing a series of analyses for various slope geometries and strength properties.Stability charts and equations are developed to estimate the factor of safety of strain-softe ning slopes from the results of traditional stability analysis based on perfectly-plastic behavior.Two example applications including an open pit mine in weak rock and clay shale slope with daylighting bedding planes are presented.The results of limit equilibrium analysis and shear strength reduction method with perfectly-plastic models were in close agreement.Using perfectly-plastic models with peak strength properties led to overly optimistic results while adopting residual strength properties gave excessively conservative outcomes.The shear strength reduction method with a strain-softening model gave realistic factors of safety while accounting for the process of strength degradation.展开更多
Complex industrial systems, including mining, have a prominent challenge in understanding the interrelationship among the cognitive processes, working environment and available equipment. The concept of cognitive work...Complex industrial systems, including mining, have a prominent challenge in understanding the interrelationship among the cognitive processes, working environment and available equipment. The concept of cognitive work analysis(CWA) transcends the traditional analytic methods of evaluating human tasks solely based on perceptual and physical traits, and rather implements the notions of behavioral and cognitive awareness indispensable for the intricacy of modern technology. In the last few decades, academic and industrial settings employ this type of analysis to set a suitable standard for a system's safety feasibility, and as a result reduce human-based errors. This research paper analyzes current CWA methods and proposes a five-level quantification model portraying the overall cognitive quality of a mining operation.展开更多
Crashes at rural intersections are frequently a result of failure to yield. As a result, agencies attempt to find countermeasures that encourage drivers to stop and yield appropriately. A number of countermeasures hav...Crashes at rural intersections are frequently a result of failure to yield. As a result, agencies attempt to find countermeasures that encourage drivers to stop and yield appropriately. A number of countermeasures have been utilized to reduce crashes and improve intersection safety. However, some treatments have been shown to have mixed results, while for others only limited information about effectiveness is available. Because even low-cost treatments require some maintenance, it is important for agencies to have good information about the effectiveness of the various treatments before investments are made. Stop sign beacons are one such low-cost measure. This paper discusses results of research which evaluated stop sign beacons. Stop sign beacons were installed at 10 stop-controlled approaches in the US state of Iowa. The beacons were set to activate only when an approaching driver was traveling over a set speed threshold which was set based on whether a driver would be able to stop. Video data were collected before, at 1-month, and at 12-month after installation. Type of stop (i.e., rolling, no-stop), stop location in reference to the stop bar, and location of initial brake application were reduced from the video data. The percentage of drivers who began braking before or after 350 feet were compared. This threshold indicates the point at which drivers would need to engage in hard braking based on approach speed and stopping sight distance. At one month, 6 of the 9 intersections experienced an increase in the percentage of vehicles braking at 350 feet or before. At 12-month, drivers at more than half of the approaches were braking sooner than the before period. Results also indicate stopping behavior improved after installation of the beacons. Most of the approaches (70%) showed an increase in the percentage of drivers who came to a full stop at 1-month compared to the period before installation. At 12-month, 71% of approaches showed an increase in drivers who came to a complete stop. Similar results were found for stopping location. Around 80% of approaches experienced an increase in the percentage of vehicle that stopped at or before the stop bar at the 1-month period after installation and 86% of approaches had an increase at 12-month.展开更多
工作场所安全行为研究在过去50年已形成丰富的知识体系,分析该领域知识流动与演化过程,展望未来研究方向,对提升我国安全生产治理现代化水平具有重要指导意义。以Web of Science数据库收录的1086篇SCI和SSCI期刊文献为样本,综合使用Cite...工作场所安全行为研究在过去50年已形成丰富的知识体系,分析该领域知识流动与演化过程,展望未来研究方向,对提升我国安全生产治理现代化水平具有重要指导意义。以Web of Science数据库收录的1086篇SCI和SSCI期刊文献为样本,综合使用CiteSpace、Histcite以及Pajek等文献计量和大规模引文网络分析工具,明确1973—2021年间工作场所安全行为研究概貌特征,挖掘该领域研究热点及其关联性,以揭示知识扩散路径。研究发现:工作场所安全行为国际研究在2003,2013年经历2次快速发展,且形成以美国、中国和澳大利亚为核心的跨国合作研究网络;工作场所安全行为国际研究经历初始萌芽、初步发展和快速发展3个主要阶段,尽管安全氛围和安全领导力一直是该领域研究热点,但不同阶段的研究热点经历了从事故伤害到安全行为、从安全文化到安全氛围、从安全领导力到安全心理契约的多维转变,体现了时代特征和现实需求。最后,从研究场景、视角、范畴、内容、对象和方法等6个方面,提出工作场所安全行为领域未来研究方向。展开更多
In order to give a new way for modeling driving behavior, identifying road traffic accident causation and solving a variety of road traffic safety problems such as driving errors prevention and driving behavior analys...In order to give a new way for modeling driving behavior, identifying road traffic accident causation and solving a variety of road traffic safety problems such as driving errors prevention and driving behavior analysis, a new driving behavior shaping model is proposed, which could be used to assess the degree of effect of driving error upon road traffic safety. Driver behavior shaping model based on driving reliability and safety analysis could be used to identify the road traffic accident causation, to supply data for driver's behavior training, to evaluate driving procedures, to human factor design of road traffic system.展开更多
基金National Natural Science Foundation of China under Grant Nos.51138001 and 51479027
文摘Abstract： The containment vessel of a nuclear power plant is the last barrier to prevent nuclear reactor radiation. Aseismic safety analysis is the key to appropriate containment vessel design. A prestressed concrete containment vessel （PCCV） model with a semi-infinite elastic foundation and practical arrangement of tendons has been established to analyze the aseismic ability of the CPR1000 PCCV structure under seismic loads and internal pressure. A method to model the prestressing tendon and its interaction with concrete was proposed and the axial force of the prestressing tendons showed that the simulation was reasonable and accurate. The numerical results show that for the concrete structure, the location of the cylinder wall bottom around the equipment hatch and near the ring beam are critical locations with large principal stress. The concrete cracks occurred at the bottom of the PCCV cylinder wall under the peak earthquake motion of 0.50 g, however the PCCV was still basically in an elastic state. Furthermore, the concrete cracks occurred around the equipment hatch under the design internal pressure of 0.4MPa, but the steel liner was still in the elastic stage and its leak-proof function soundness was verified. The results provide the basis for analysis and design of containment vessels.
文摘This paper discusses some issues on human reliability model of time dependent human behavior. Some results of the crew reliability experiment on Tsinghua training simulator in China are given, Meanwhile, a case of calculation for human error probability during anticipated transient without scram (ATWS) based on the data drew from the recent experiment is offered.
基金financially supported by the Natural Sciences and Engineering Research Council of Canada(NSERC:RES0014117).
文摘Stability analysis of strain-softening slopes is carried out using the shear strength reduction method and Mohr-Coulomb model with degrading cohesion and friction angle.The e ffect of strain-softening behavior on the slope factor of safety is investigated by performing a series of analyses for various slope geometries and strength properties.Stability charts and equations are developed to estimate the factor of safety of strain-softe ning slopes from the results of traditional stability analysis based on perfectly-plastic behavior.Two example applications including an open pit mine in weak rock and clay shale slope with daylighting bedding planes are presented.The results of limit equilibrium analysis and shear strength reduction method with perfectly-plastic models were in close agreement.Using perfectly-plastic models with peak strength properties led to overly optimistic results while adopting residual strength properties gave excessively conservative outcomes.The shear strength reduction method with a strain-softening model gave realistic factors of safety while accounting for the process of strength degradation.
文摘Complex industrial systems, including mining, have a prominent challenge in understanding the interrelationship among the cognitive processes, working environment and available equipment. The concept of cognitive work analysis(CWA) transcends the traditional analytic methods of evaluating human tasks solely based on perceptual and physical traits, and rather implements the notions of behavioral and cognitive awareness indispensable for the intricacy of modern technology. In the last few decades, academic and industrial settings employ this type of analysis to set a suitable standard for a system's safety feasibility, and as a result reduce human-based errors. This research paper analyzes current CWA methods and proposes a five-level quantification model portraying the overall cognitive quality of a mining operation.
文摘Crashes at rural intersections are frequently a result of failure to yield. As a result, agencies attempt to find countermeasures that encourage drivers to stop and yield appropriately. A number of countermeasures have been utilized to reduce crashes and improve intersection safety. However, some treatments have been shown to have mixed results, while for others only limited information about effectiveness is available. Because even low-cost treatments require some maintenance, it is important for agencies to have good information about the effectiveness of the various treatments before investments are made. Stop sign beacons are one such low-cost measure. This paper discusses results of research which evaluated stop sign beacons. Stop sign beacons were installed at 10 stop-controlled approaches in the US state of Iowa. The beacons were set to activate only when an approaching driver was traveling over a set speed threshold which was set based on whether a driver would be able to stop. Video data were collected before, at 1-month, and at 12-month after installation. Type of stop (i.e., rolling, no-stop), stop location in reference to the stop bar, and location of initial brake application were reduced from the video data. The percentage of drivers who began braking before or after 350 feet were compared. This threshold indicates the point at which drivers would need to engage in hard braking based on approach speed and stopping sight distance. At one month, 6 of the 9 intersections experienced an increase in the percentage of vehicles braking at 350 feet or before. At 12-month, drivers at more than half of the approaches were braking sooner than the before period. Results also indicate stopping behavior improved after installation of the beacons. Most of the approaches (70%) showed an increase in the percentage of drivers who came to a full stop at 1-month compared to the period before installation. At 12-month, 71% of approaches showed an increase in drivers who came to a complete stop. Similar results were found for stopping location. Around 80% of approaches experienced an increase in the percentage of vehicle that stopped at or before the stop bar at the 1-month period after installation and 86% of approaches had an increase at 12-month.
文摘工作场所安全行为研究在过去50年已形成丰富的知识体系,分析该领域知识流动与演化过程,展望未来研究方向,对提升我国安全生产治理现代化水平具有重要指导意义。以Web of Science数据库收录的1086篇SCI和SSCI期刊文献为样本,综合使用CiteSpace、Histcite以及Pajek等文献计量和大规模引文网络分析工具,明确1973—2021年间工作场所安全行为研究概貌特征,挖掘该领域研究热点及其关联性,以揭示知识扩散路径。研究发现:工作场所安全行为国际研究在2003,2013年经历2次快速发展,且形成以美国、中国和澳大利亚为核心的跨国合作研究网络;工作场所安全行为国际研究经历初始萌芽、初步发展和快速发展3个主要阶段,尽管安全氛围和安全领导力一直是该领域研究热点,但不同阶段的研究热点经历了从事故伤害到安全行为、从安全文化到安全氛围、从安全领导力到安全心理契约的多维转变,体现了时代特征和现实需求。最后,从研究场景、视角、范畴、内容、对象和方法等6个方面,提出工作场所安全行为领域未来研究方向。
文摘In order to give a new way for modeling driving behavior, identifying road traffic accident causation and solving a variety of road traffic safety problems such as driving errors prevention and driving behavior analysis, a new driving behavior shaping model is proposed, which could be used to assess the degree of effect of driving error upon road traffic safety. Driver behavior shaping model based on driving reliability and safety analysis could be used to identify the road traffic accident causation, to supply data for driver's behavior training, to evaluate driving procedures, to human factor design of road traffic system.
