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41.
The 2010 Manila amendments to the Standards of Training, Certification and Watchkeeping Code (STCW) was adopted by the idea to render the profession more attractive to the seafarers, particularly to cadets. It is possible to ensure greater attraction only by providing suitable and safe working conditions on board to cadets. This study analyses occupational accidents and near misses encountered by ocean going deck cadets, who received A-II/I training, during their sea training. The aim of this study was to determine causal factors influencing work accidents and to propose several recommendations for the safety of deck cadets. A total of 857 officer candidates, who received maritime education at university level in Turkey, were interviewed. The Analytic Hierarchy Process (AHP) method was used in the study to analyse the occupational accidents. As a result of this study on deck cadets, the most risky areas for work accidents were found to be the deck (39.9%), cargo areas (35.7%), areas used for manoeuvring operations (including winch areas and areas in which berthing, unberthing, and anchoring operations take place) (16.1%), and accommodation areas (8.3%). The most important root causes for occupational accidents were identified as not using personal protective equipment (24.2%), haste (22.6%), and presence in inappropriate places (13.6%). This study offers some important insight into the prevention of occupational accidents, and includes suggestions and advisory opinions of sector representatives. As a result of this study, several recommendations for the prevention of accidents are proposed.  相似文献   
42.
文章采用了空气动力、水动力、控制与弹性完全耦合的时域模拟方法研究了张力腿式浮式风机平台的动力响应.水动力载荷的计算采用了三维势流理论与Morison公式.空气动力载荷的计算采用了叶素动量理论和广义动态尾流理论.利用FAST软件得到了张力腿式浮式风机平台响应的时域结果,并分析了其动力响应特性.建立了描述平台纵荡运动的非线性微分方程,并采用了摄动方法求得其近似解,解释了纵荡运动中由非线性粘性效应引起的高频响应.对数值模拟结果的分析表明高频的响应分量对平台的动力性能有显著的影响.  相似文献   
43.
Emissions of GHG from the transport sector and how to reduce them are major challenges for policy makers. The purpose of this paper is to analyse the level of greenhouse gas (GHG) emissions from ships while in port based on annual data from Port of Gothenburg, Port of Long Beach, Port of Osaka and Sydney Ports. Port call statistics including IMO number, ship name, berth number and time spent at berth for each ship call, were provided by each participating port. The IMO numbers were used to match each port call to ship specifications from the IHS database Sea-web. All data were analysed with a model developed by the IVL Swedish Environmental Research Institute for the purpose of quantifying GHG emissions (as CO2-equivalent) from ships in the port area. Emissions from five operational modes are summed in order to account for ship operations in the different traffic areas. The model estimates total GHG emissions of 150,000, 240,000, 97,000, and 95,000 tonnes CO2 equivalents per year for Gothenburg, Long Beach, Osaka, and Sydney, respectively. Four important emission-reduction measures are discussed: reduced speed in fairway channels, on-shore power supply, reduced turnaround time at berth and alternative fuels. It is argued that the potential to reduce emissions in a port area depends on how often a ship revisits a port: there it in general is easier to implement measures for high-frequent liners. Ships that call 10 times or less contribute significantly to emissions in all ports.  相似文献   
44.
Flex-Lay铺管船是柔性管线铺设平台,通过分析全球Flex-Lay铺管船发展现状,Flex-Lay铺管船正向专业化和多功能化方向发展,为我国Flex-Lay铺管船发展提供借鉴。  相似文献   
45.
Fuel-switching personal transportation from gasoline to electricity offers many advantages, including lower noise, zero local air pollution, and petroleum-independence. But alleviations of greenhouse gas (GHG) emissions are more nuanced, due to many factors, including the car’s battery range. We use GPS-based trip data to determine use type-specific, GHG-optimized ranges. The dataset comprises 412 cars and 384,869 individual trips in Ann Arbor, Michigan, USA. We use previously developed algorithms to determine driver types, such as using the car to commute or not. Calibrating an existing life cycle GHG model to a forecast, low-carbon grid for Ann Arbor, we find that the optimum range varies not only with the drive train architecture (plugin-hybrid versus battery-only) and charging technology (fast versus slow) but also with the driver type. Across the 108 scenarios we investigated, the range that yields lowest GHG varies from 65 km (55+ year old drivers, ultrafast charging, plugin-hybrid) to 158 km (16–34 year old drivers, overnight charging, battery-only). The optimum GHG reduction that electric cars offer – here conservatively measured versus gasoline-only hybrid cars – is fairly stable, between 29% (16–34 year old drivers, overnight charging, battery-only) and 46% (commuters, ultrafast charging, plugin-hybrid). The electrification of total distances is between 66% and 86%. However, if cars do not have the optimum range, these metrics drop substantially. We conclude that matching the range to drivers’ typical trip distances, charging technology, and drivetrain is a crucial pre-requisite for electric vehicles to achieve their highest potential to reduce GHG emissions in personal transportation.  相似文献   
46.
管道内防腐层补口技术研究进展   总被引:1,自引:0,他引:1  
管道内衬或内防腐涂层现场施焊时,焊缝两侧的防腐层会由于高温作用而破坏,使环焊缝处不能得到有效的保护,内补口技术也成为影响管道质量的主要瓶颈。文中介绍了国内外主要的内补口技术,如内补口机法、内衬保护套(管)焊接法、不锈钢接头法、机械连接法等,并指出各方法的特点。文中还就内补口技术的质量控制和研究方向等提出了建议。  相似文献   
47.
Public transit systems with high occupancy can reduce greenhouse gas (GHG) emissions relative to low-occupancy transportation modes, but current transit systems have not been designed to reduce environmental impacts. This motivates the study of the benefits of design and operational approaches for reducing the environmental impacts of transit systems. For example, transit agencies may replace level-of-service (LOS) by vehicle miles traveled (VMT) as a criterion in evaluating design and operational changes. In previous work, we explored the unintended consequences of lowering transit LOS on emissions in a single-technology transit system. Herein, we extend the analysis to account for a more realistic case: a transit system with a hierarchical structure (trunk and feeder lines) providing service to a city where demand is elastic. By considering the interactions between the trunk and the feeder systems, we provide a quantitative basis for designing and operating integrated urban transit systems that can reduce GHG emissions and societal costs. We find that highly elastic transit demand may cancel emission reduction potentials resulting from lowering LOS, due to demand shifts to lower occupancy vehicles. However, for mass transit modes, these potentials are still significant. Transit networks with buses, bus rapid transit or light rail as trunk modes should be designed and operated near the cost-optimal point when the demand is highly elastic, while this is not required for metro. We find that the potential for unintended consequences increases with the size of the city. Our results are robust to uncertainties in the costs and emissions parameters.  相似文献   
48.
使用自行设计的程序温控的催化反应平台和模拟配气系统相连接,测试并获得催化剂的催化还原NOx和催化氧化PM的准确的催化性能数据.使用该催化反应平台和常柴CZ2102型柴油机实验平台相连接,获得在稀燃条件下介孔镧铈锆铝复合氧化物对PM和NOx的催化处理实验的应用数据.为同时去除柴油机排气污染物PM颗粒和NOx的工程应用打下坚实的基础.  相似文献   
49.
使用WAMIT软件建立了OC3-Hywind Spar式浮式风机模型,联合FAST软件计算了浮式风机在不同工况下的幅值响应算子;结合为南海海域波浪条件优化后的JONSWAP谱,对浮式风机进行了不同工况下的响应谱分析及最大响应值计算;进一步阐述了浮式平台结构构型参数的变化对整体结构在南海相应工况下的运动影响。  相似文献   
50.
In this paper, airline energy efficiency is divided into three stages: the operations stage, the services stage and the sales stage. Greenhouse gas emissions are treated as an undesirable output of the services stage. This new three-stage strategic operating framework is a modification of existing models. A new model, Virtual Frontier Network Range Adjusted Measure with weak disposability, is proposed to evaluate the efficiencies of 22 international airlines, from 2008 to 2012. The results show that the new model can establish more reasonable rankings and confirm new benchmarking airlines and that inclusion in the European Union’s Emissions Trading Scheme has had little influence on the improvement of airline energy efficiency.  相似文献   
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