A moderated mediation test of personality,coping, and health among deployed soldiers

Our study examines how personality and coping influence soldiers' psychological health among 648 US Army personnel who were at that time deployed in Iraq at the height of an insurgency. Conscientiousness, neuroticism, and extraversion were associated with different coping behaviors, and these were in turn related to psychological distress. Conscientiousness was positively associated with problem‐focused coping and negatively with avoidance coping, whereas neuroticism was most positively associated with avoidance coping. Extraversion was positively related to both seeking social support and avoidance coping. As expected, avoidance coping was positively associated with psychological distress. Coping style explained more variance in the relationship between personality and distress among soldiers who perceived higher levels of threat, thus supporting a moderated mediation hypothesis. We discuss implications for facilitating the stress coping of workers who face acute and potentially traumatic stress exposures. Copyright © 2011 John Wiley & Sons, Ltd.     

Prediction of minimum ignition energy of aerosols using flame kernel modeling combined with flame front propagation theory

Flammable aerosols have created many fire and explosion hazards in the process industry, but the flammability of aerosols has not been fully understood. The minimum ignition energy has been widely used as an indicator for flammability of combustible mixtures, but the amount of experimental data on the minimum ignition energy of aerosols is very limited. In this work, the minimum ignition energy of tetralin aerosols is predicted using an integrated model. The model applies the flame front propagation theory in aerosol systems to the growth of the flame kernel, which was created during the spark discharge in the ignition process. The aerosol minimum ignition energy was defined as the minimum level of energy in the initial flame kernel to maintain the kernel temperature above the minimum ignition temperature of 1073 K specific for tetralin aerosols during the kernel growth. The minimum ignition energy obtained in the model is influenced by the fuel-air equivalence ratio and the size of the aerosol droplets. For tetralin aerosols of 40 μm diameter, E_min decreases significantly from 0.32 mJ to 4.3 × 10 e⁻³ mJ when the equivalence ratio rises from 0.57 to 1.0. For tetralin aerosols of 0.57 equivalence ratio, E_min increases from as 0.09 mJ to 0.32 mJ when the droplet diameter rises from 10 μm to 60 μm. The trends are in agreement with previous experimental observations. The method used in current work has the potential to prediction of the minimum ignition energy of aerosol.     

Research and application of risk and condition based maintenance task optimization technology in an oil transfer station

Oil transfer stations of PetroChina mostly scatter in Gobi, mountain areas or other sparsely populated areas, inconvenient transportation and absent professional engineers often delay the best time to repair the machines. Time-or interval-based maintenance (TBM) accounts for almost 100%, while, On-condition maintenance and other proactive maintenance are seldom adopted. TBM not only can't prevent happens of equipment fault but also cause the waste of the maintenance resource. In order to allocate maintenance resources reasonably, ascertain the minimum preventive maintenance requirement, ensure the reliability, availability and safety, this paper carries out a research on Risk and Condition Based Maintenance (RCBM) task optimization technology. Utilizing the internet of things (IOT), real-time database, signal-processing, Gray Neural Network, probability statistical analysis and service oriented architecture (SOA) technology, a Risk and Condition Based Indicator Decision-making System (RCBIDS) is built. RCBIDS integrates RCM, condition monitoring system (CMS), key performance management module, file management module, fault and defect management module, maintenance management module together, which aims to realize remote condition monitoring, maintenance technical support services (TSS), quantitative maintenance decision-making, and to ensure the Reliability, Availability, Maintainability and Safety (RAMS). The Predictive Maintenance Indicator model, reliability prediction model and Key Performance Indicator (KPI) model, which are embedded in the RCBIDS, are constructed separately. An engineering case shows that the risk and condition based maintenance task optimization technology can be used to optimize maintenance content and maintenance period, to minimize maintenance deficiencies and maintenance surplus, and to prolong the lifespan of equipment.     

废催化剂中金属组分回收利用概述

废催化剂中金属组分的回收利用具有经济性和环保性,从工程项目开发的角度,对废催化剂中金属组分回收利用技术与经济等方面的问题进行了概述,主要包括废催化剂原料的收集与分类、回收技术方案选择、经济评价及关键理论,同时也指出了相关问题及发展前景。     

应用瞬变电磁法防治煤矿顶板砂岩水的实践

研究了华北型煤田顶板砂岩的赋水规律,总结出顶板砂岩水的综合防治方法。应用瞬变电磁法探测某煤矿顶板岩层发育的含(导)水构造,为安全生产工作提供了技术指导。     

天然气管道失效个人生命风险评价技术研究

为研究天然气长输管道失效个人生命风险,提出一种以人员伤亡概率为指标的天然气管道失效后果风险评价方法。基于天然气管道的失效概率和失效致死长度参数,建立天然气长输管道生命风险评价模型。用该模型,对国内某城市住宅小区内带腐蚀缺陷的天然气管线进行定量风险分析。借鉴英国天然气输送公司数据,确定天然气管线个人生命风险值。案例证明,用所建立的天然气管道失效个人生命风险评价模型能够有效地分析带缺陷天然气管道失效后果,实现天然气管道的个人安全生命风险全定量评价。     

可燃固体表面火蔓延行为研究进展与展望

固体可燃物表面火蔓延是森林火灾、建筑火灾以及工业火灾中普遍存在的燃烧现象,是火灾研究的基础问题。对固体可燃物表面火蔓延行为进行分类,评述国内外的固体可燃物表面火蔓延行为研究现状和目前存在的主要问题。总结固体可燃物表面火蔓延试验研究的技术手段,对比分析不同因素对建立固体可燃物表面火蔓延行为理论模型的影响。这些因素包括环境流场、化学反应动力学、热解气体组分和炭化过程等。概要介绍固体可燃物表面火蔓延计算模拟的优势。最后指出固体可燃物火蔓延行为研究的发展趋势,并提出未来若干重点研究方向。     

Parallel and serial methods of calculating thermal insulation in European manikin standards

Standard No. EN 15831:2004 provides 2 methods of calculating insulation: parallel and serial. The parallel method is similar to the global one defined in Standard No. ISO 9920:2007. Standards No. EN 342:2004, EN 14058:2004 and EN 13537:2002 refer to the methods defined in Standard No. EN ISO 15831:2004 for testing cold protective clothing or equipment. However, it is necessary to consider several issues, e.g., referring to measuring human subjects, when using the serial method. With one zone, there is no serial-parallel issue as the results are the same, while more zones increase the difference in insulation value between the methods. If insulation is evenly distributed, differences between the serial and parallel method are relatively small and proportional. However, with more insulation layers overlapping in heavy cold protective ensembles, the serial method produces higher insulation values than the parallel one and human studies. Therefore, the parallel method is recommended for standard testing.     

高应力煤巷卸压孔布置方式对卸压效果影响分析

高应力是造成深部煤巷大变形的主要因素。钻孔卸压已成为高应力区围岩稳定性控制的主要方法之一。基于钻孔卸压原理,以实际工程为背景,设计了三种卸压孔布置方式,并采用数值模拟的方法对不同卸压孔布置方式的卸压效果进行计算和对比分析。结果表明:卸压孔布置方式对卸压效果影响显著,卸压孔五花布置时,卸压效果最为明显;卸压孔周围形成卸压圈,卸压圈相互叠加,卸压范围增大;巷帮布置卸压孔使巷道周边形成的应力峰值向远离巷道的围岩深部移动,五花布置卸压孔时,不仅能够使应力峰值向深部转移,而且降低了应力峰值,有效改善围岩应力环境;卸压孔产生的卸压区,为巷道围岩提供给了一定的变形补偿空间,减小了巷道变形,卸压孔五花布置时,巷道变形最小,与无卸压孔时相比,巷道实体煤帮整体变形量减小了73.9%,顶板最大沉降量减小了40%,控制变形效果明显。     

建设工程融合式外部安全监管研究

介绍了融合式外部安全监管的提出背景以及在此背景下的具体内涵;融合式外部监管的任务是按照企业、项目的安全生产目标以及国家安全生产的相关法律法规、标准规范而制定的,其相关的工作内容主要以项目安全总监的工作角色为主要载体进行开展,既包括了对项目管理行为的监管,又包括了对项目隐患和违章现象的制止和约束;介绍了安全总监约谈制度的内容,并对安全总监的监管流程进行了说明,包括具体的管理手段和措施;最后指出项目安全总监的在项目管理中的角色是项目安全生产第一监管人。