基于模糊贴近度和熵权的航空装备维修安全综合评价

航空装备维修安全是确保装备飞行安全的重要因素,为提高航空装备飞行的安全性,需要对航空装备维修安全进行准确评价。根据航空装备维修安全评价涉及的不确定性问题,采用模糊数学和熵理论,提出一种基于模糊贴近度和熵权的航空装备维修安全综合评价方法。在建立航空装备维修安全评价指标体系的基础上,采用熵确定各指标的权重值、加权平均算子确定综合评价集,利用非对称贴近度进行决策分析。通过对某型飞机调查数据的算例分析,确定航空装备维修安全的主要影响因素,得出该型飞机维修安全水平的评价值。     

国家地表水水质自动监测站运行维护及管理探讨

根据国家地表水自动监测站运行维护要求和未来发展趋势,从运维机构的角度,对水质自动站的工作职责、日常运行维护、质量管理等方面提出改进对策和针对性建议.     

海上舰船装备维修保障建设探讨

在信息化海战的条件下,对舰船装备的破坏性、毁灭性打击的力度不断增大,对海军舰船装备维修保障能力提出了新的要求.在分析了海上舰船装备维修保障使命任务的基础上,明确了加强海上舰船装备维修保障体系建设的具体内容,并提出了具体措施,大大增强了我海军舰艇装备的可靠性和可维修性,提高了舰艇部队的整体作战能力.     

海洋环境服役飞机的全面腐蚀控制

从结构设计、材料筛选、表面处理、有机防护体系、防锈剂的应用、维护/维修、人员培训等方面,分析了国外海洋服役飞机的腐蚀防护与控制的发展状况。从腐蚀与防护系统工程的角度,提出了我国海洋服役飞机全面腐蚀控制的发展建议,主要包括加强细节的密封防水设计、应用先进高性能防护技术、加强维护/维修中技术与产品的研发和应用等几个方面。最终建立起海洋服役飞机表面防护研究体系,保证了海洋服役飞机的研制、生产和使用的顺利进行,全面提高了海洋服役飞机的使用寿命。     

基于不确定性理论的排水管网多泵站启停液位筛选研究

基于暴雨管理模型(storm water management model,简称SWMM),构建实验管网模型,基于不确定性理论,采用拉丁超立方法采样,根据管网运行管理目标选择可行的泵站启动液位调控方案,并对多个泵站的运行控制参数进行统计分析,筛选合理的泵站启停液位区间。结果表明该方法可以有效分析控制参数的不确定性,为排水管网控制方案的科学制定提供有效分析途径。     

噪声自动监测系统的运行维护管理

对噪声自动监测系统在运行过程中遇到的各种情况进行分类和总结,详细介绍了南通市环境监测中心站的相关工作经验,提出从设备故障、突发事件、软件错误等方面出发,对噪声自动监测的运行维护进行综合管理。     

TEOM~ RP1400a(PM_(10))测尘仪日常维护和常见故障处理

介绍TEOMR○RP1400a(PM10)测尘仪原理、工作过程以及日常维护、质量控制和常见故障的排除方法。     

基于X射线荧光分析原理的大气重金属在线分析仪的维护与质控

近年来大气细颗粒物中重金属元素成分的监测是细颗粒物化学成分监测的热点之一,这一类物质的在线监测在国内应用越来越多,笔者研究和探讨了影响X射线荧光法大气重金属在线分析仪器运行质量的主要运维工作和质量控制方法,提出了该仪器在线监测中的运维及质控要求,为环境监测工作者提供参考,以获得更加准确的监测数据。     

美国环境空气监测培训课程设置的经验与启示

详细介绍了美国环境空气监测培训课程设置的方法和结构,分析了其在课程的目标规划、内容设计和指导人员自学方面的主要做法,总结出应从监测人员能力和知识要求角度设定培训目标,以技术性实用性内容为主设计课程环节,将指导支持人员自学摆在更突出位置。借鉴美国经验,文章对探索我国环境空气监测培训的课程设置提出了具体建议。     

A clustering approach to integrate traffic safety in road maintenance prioritization

Objectives: We combine data on roads and crash characteristics to identify patterns in road traffic crashes with regard to road characteristics. We illustrate how combined analysis of data regarding road maintenance, maintenance costs, road characteristics, crash characteristics, and geographical location can enrich road maintenance prioritization from a traffic safety perspective.

Methods: The study is based on traffic crash data merged with road maintenance data and annual average daily traffic (AADT) collected in Denmark. We analyzed 3,964 crashes that occurred from 2010 to 2015. A latent class clustering (LCC) technique was used to identify crash clusters with different road and crash characteristics. The distribution of crash severity and estimated road maintenance costs for each cluster was found and cluster differences were compared using the chi-square test. Finally, a map matching procedure was used to identify the geographical distribution of the crashes in each cluster.

Results: Results showed that based on road maintenance levels there was no difference in the distribution of crash severity. The LCC technique revealed 11 crash clusters. Five clusters were characterized by crashes on roads with a poor maintenance level (levels 4 and 3). Only a few of these crashes included a vulnerable road user (VRU) but many occurred on roads without barriers. Four clusters included a large share of crashes on acceptably maintained roads (level 2). For these clusters only small variations in road characteristics were found, whereas the differences in crash characteristics were more dominant. The last 2 clusters included crashes that mainly occurred on new roads with no need for maintenance (level 1). Injury severity, estimated maintenance costs, and geographical location were found to be differently distributed for most of the clusters.

Conclusions: We find that focusing solely on road maintenance and crash severity does not provide clear guidance of how to prioritize between road maintenance efforts from a traffic safety perspective. However, when combined with geographical location and crash characteristics, a more nuanced picture appears that allows consideration of different target groups and perspectives.