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101.
Leading indicators, one type of accident precursor, are conditions, events or measures that precede an undesirable event and that have some value in predicting the arrival of the event, whether it is an accident, incident, near miss, or undesirable safety state. Leading indicators are associated with proactive activities that identify hazards and assess, eliminate, minimize and control risk. An empirical analysis of leading indicators of safety for an international energy transportation company was undertaken, utilizing a previously validated research model. Quantitative safety performance and qualitative safety culture data were obtained from 943 participants on 37 vessels from three fleets in the organization. Organizational, vessel and individual safety factors and leading indicators were identified and an analysis of fleet, vessel, and individual safety cultures was undertaken. The results indicate that individual and vessel-level leading indicators can provide important input to an organization's continuous safety measuring and monitoring systems.  相似文献   
102.
中高速船加装减纵摇组合附体模型试验   总被引:8,自引:1,他引:7  
对某常规单体排水式圆舭导弹护卫艇进行加装减纵向运动组合附体的模型快速性试验和耐波性试验。首先进行了小尺度模型的静水阻力试验和规则波试验,优选出阻力和减摇效果均较优的方案。进行了较大尺度模型的静水阻力试验、规则波试验和不规则波试验。试验结果表明减纵向运动组合附体可显著抑制舰船的纵向运动,包括垂荡、纵摇、艏、中、艉部加速度,以及砰击、上浪、波浪增阻等,经优化设计的组合附体尺度和布局对艇静水阻力基本没有影响。  相似文献   
103.
通过具体工点介绍采用土工格室加固既有线路基基床工程的现场运用及试验情况。结果表明,用土工格室加固既有线路基基床,具有较好的推广前景。  相似文献   
104.
The westward evolution of an open-sea anticyclonic eddy along the western Algerian Basin is shown, for the first time, by means of 15 buoy trajectories and remote sensing observations. For 3 months, the buoy trajectories described several anticyclonic loops in periods of 4–21 days. The eddy's movement, translation, and rotation were separated with a kinematic model, resulting in a mean translation speed of 2 km/day, which fits the self-propulsion speed predicted on theoretical models for isolated eddies on a beta plane. Fluctuations in translation speed were associated with advection of the mean flow and topographic interactions. Both mechanisms changed the eddy's horizontal shape from circular to elliptical, inducing fluctuations in its swirl velocity and solid-body rotation. The initial stage of the eddy is an isolated asymmetric dipole, comprised by a small cyclone and a large anticyclone, the latter generated from a frontal instability, which under the Coriolis term acquires anticyclonic relative vorticity. During its first days of life, the anticyclonic eddy was shallow Ro=0.9 and small (diameter less than 50 km). Later on, it reached a diameter of 150 km and a vertical structure of 3 km (Ro=0.1). A retrospective analysis with infrared images shows that the eddy's generation took place at about 3–4°E. Then, the eddy completed a counterclockwise circuit never before reported in other studies and ended up at the entrance of the Algerian Basin, where the interaction with the topography and the coastal instability induced its decay. The eddy's life span was 10 months. Computations of the heating rate following clusters of buoy trajectories show fluctuations throughout the eddy's journey, induced by advection and a seasonal warming.  相似文献   
105.
中高速船加装减纵向运动组合附体实船试验   总被引:7,自引:1,他引:6  
对一加装了减纵向运动组合附体的高速艇和原型艇进行了海上对比试验,并对试验结果进行了分析。试验时两艇并行前进,以便从现象上直接观察加装减纵向运动组合附体的效果。试验结果证实,组合附体减纵向运动效果显著,艏部加速度降幅可达到68%,纵摇角降幅可达到40%,加装组合附体的艇在较高海情中顶浪时可高速航行,且速度越高运动越平稳,在波浪中基本没有失速。  相似文献   
106.
The ballast water from ships carries marine organisms that have invasive potential. The International Maritime Organization Ballast Water Management Convention (2004) requires ballast water exchange or ballast water management (BWM) systems either onboard or ashore. Ships can be exempted on the basis of risk assessment, when exclusively sailing between specific ports or in an enclosed area. In reply to our questionnaire, the shipping sector argues that the North Sea is ecologically homogeneous and exemptions could therefore be granted. This paper proposes that the North Sea area is, in fact, not homogeneous in terms of hydrographical and biological conditions; therefore, ballast water is a relevant transport mechanism for organisms. Within the North Sea, the short shipping routes indicate a high risk for survival. We examined actual simulation models for ballast water risk assessment in the North Sea, and we have identified the major parameters that need to be included in such models. These models provided a basis; they further need to be combined and adapted for the purpose of evaluating the rationale for an exemption. We concluded that exemptions from BWM are not recommended for the North Sea area. Anticipating the Ballast Water Management Convention, ship owners might do well to study possibilities for installing BWM systems onboard.  相似文献   
107.
发动机悬置系统性能的好坏是影响车辆乘坐舒适性的重要因素,而悬置软垫的刚度又是关键。本文以某新能源客车动力总成的悬置系统设计为例,介绍多动力总成的悬置系统的弯矩校核、系统解耦、软垫刚度计算,以及悬置系统设计的基本方法和步骤。  相似文献   
108.
This first part of the state-of-the art focuses on the origins of road safety modeling, covering data, early models and the public health context of model formulation and use.  相似文献   
109.
The third part of the state-of-the-art focuses on the future of road safety modeling and on conjectures concerning the evolution of national safety indicators. In the absence of econometric developments specific to road safety modeling, the research future must rely on pre-existing statistical procedures of econometrics applied to discrete/count and to aggregate data. In terms of contents, growing interest in the heterogeneity of road accident outcomes by category of victims could lead to treatments of this issue across research streams, say by top-down and bottom-up developments, but this speculation does not rest on extant adequate formulations of the issue of road user class and victim analysis. But understanding the time profile of aggregate national performance indicators is quite another matter.  相似文献   
110.
The Mediterranean area plays a pivotal role within the definition and implementation of regional strategies for integrated coastal zone management (ICZM). Under the umbrella of the Regional Framework Operation BeachMed-e, a research project was carried out in five Mediterranean EU regions (East Macedonia and Thrace in Greece, Lazio, Liguria, and Emilia Romagna in Italy and Languedoc-Roussillon in France), in order to study the different approaches to ICZM that have been applied and also to test new approaches to these regions. The aim of this article is to present and discuss the results of the common surveys conducted in order to investigate the institutional stakeholders’ perception on ICZM in the five Mediterranean regions considered. The results are presented region by region, while comparisons are carried out among regions. Summarizing the results it can be stated that some differences and common problems affecting the coastal decision-makers of the five Mediterranean regions considered were identified. Particularly, stakeholders involved in coastal management generally perceived a lack of collaboration and a poor information exchange in all the regions, resulting sometimes in a lack of awareness on coastal erosion issues.  相似文献   
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