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31.
大型半潜式钻井平台安全关键技术研究 总被引:1,自引:1,他引:0
BINGO—9000型平台是目前世界上最先进的第五代半潜式钻井平台,能在深海(工作水深3000m),恶劣气候海况(零下20℃、风速41m/s、浪高32m)下开采石油。以BINGO—9000型平台为例,介绍了平台结构和压载状态实时监测系统设计的关键技术问题,以及基于疲劳寿命分析的结构设计思想。展开了该平台波浪载荷的分析计算,在此基础上对主体结构进行了三维有限元强度分析。对平台特殊结构如K型管节点及支撑结构和立柱结构进行了强度分析和疲劳寿命分析。还研究了平台吃水数据采集、压载状态监测等技术。通过以上关键技术的研究,平台结构设计更趋安全可靠合理,既具有必需的强度储备,又可减轻结构重量。 相似文献
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The transportation fare system influences the mobility of a region and the life quality of its inhabitants. This study aims to evaluate a region's optimal fare system by using the analytic hierarchy process, based on a survey among transportation experts, divided into three categories: operators, professors/consultants and government officials. The results are presented divided by category and overall, and the performance of the most important relative criteria to establish a fare system is determined. The most important criterion according to all the selected experts was the fare price, with 21.5%. The fare system determined as the best was distance/zone (31.1%) and the worst was a flat fare system (7.2%). In addition, we show the influence of the fare price criterion in each fare system through sensitivity charts and highlight its importance for all three groups of experts to evaluate the fare system. 相似文献
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Maarten Messagie Nele Sergeant Surendraprabu Rangaraju Javier San Felix Forner Luis Oliveira Thierry Coosemans 《运输规划与技术》2015,38(3):335-346
The European Clean Vehicle Directive was introduced in 2009 to create an obligation on public authorities to take into account the impact of energy consumption, carbon dioxide (CO2) emissions and pollutant emissions into their purchasing decisions for road transport vehicles. This should stimulate the market for clean and energy-efficient vehicles and improve transport's impact on environment, climate change and energy use. Therefore the so-called ‘Operational Lifetime Cost’ of a vehicle is calculated, divided into the cost for energy consumption, CO2 and pollutant (nitrous oxide, particulate matter, non-methane hydrocarbons) emissions. In Belgium, a different methodology has been developed to calculate the environmental impact of a vehicle, called ‘Ecoscore’, based on a well-to-wheel approach. More pollutants are included compared to the Clean Vehicle methodology, but also indirect emissions are taken into account. In this paper, both methodologies are compared and used to analyze the environmental performance of passenger cars with different fuel types and from different vehicle segments. Similar rankings between both methodologies are obtained; however, the large impact of energy use (and CO2 emissions) in the Clean Vehicle methodology disadvantages compressed natural gas cars, as well as diesel cars equipped with particulate filters, compared to the Ecoscore methodology. 相似文献
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Transportation - In this paper, we propose a mixed methods quantitative and qualitative approach to capture fully the measurable and less tangible social impacts of transport projects on local... 相似文献
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This paper studies the supply variables that influence the destination and route choices of users of a bicycle sharing system in the Chilean city of Santiago. A combined trip demand logit model is developed whose explanatory variables represent attributes relating to the topology of the possible routes and other characteristics such as the presence of bikeways, bus service and controlled intersections. The data for the explanatory variables and system users were collected through field surveys of the routes and interviews conducted at the system stations. The results of the model show that proximity to stops on the Santiago Metro and the existence of bikeways are the main factors influencing destination and route choices. Also indicated by the model estimates are gender differences, a preference for tree-lined routes and an avoidance of routes with bus services. Finally, the outcomes reveal considerable potential for the integration of bicycle sharing systems with Metro transit. 相似文献
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A method to evaluate equitable accessibility: combining ethical theories and accessibility-based approaches 总被引:3,自引:0,他引:3
In this paper, we present the case that traditional transport appraisal methods do not sufficiently capture the social dimensions of mobility and accessibility. However, understanding this is highly relevant for policymakers to understand the impacts of their transport decisions. These dimensions include the distribution of mobility and accessibility levels over particular areas or for specific population groups, as well as how this may affect various social outcomes, including their levels of participation, social inclusion and community cohesion. In response, we propose a method to assess the socially relevant accessibility impacts (SRAIs) of policies in some of these key dimensions. The method combines the use of underlying ethics principles, more specifically the theories of egalitarianism and sufficientarianism, in combination with accessibility-based analysis and the Lorenz curve and Gini index. We then demonstrate the method in a case study example. Our suggestion is that policymakers can use these ethical perspectives to determine the equity of their policies decisions and to set minimum standards for local transport delivery. This will help them to become more confident in the development and adoption of new decision frameworks that promote accessibility over mobility and which also disaggregate the costs and benefits of transport policies over particular areas or for specific under-served population groups. 相似文献
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This article presents a summary of the analyses and set of recommendations given by a committee of transit specialists gathered by the Minister of Transport of Chile aiming at improving Transantiago, the new transit system recently inaugurated for Santiago. This summary focuses on those recommendations directed towards improving the efficiency, service quality and sustainability of mass public transportation systems in major cities in the developing world and that could be implemented in a short term (within two years). Three broad dimensions of public transit are considered: competition and regulation; investment, financing, fares and subsidies; and the operation and use of infrastructure, design, inspection and control. Although the study grew out of the needs and characteristics of a city such as Santiago (Chile), and of the virtues and deficiencies of Transantiago, much of the analyses and recommendations could be adopted and implemented in the major cities of developed countries in Europe, North America and Asia. 相似文献
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Most countries contemplating the introduction of competition-based organizational forms did not perceive the British deregulated bus regime to be the way forward. A deeper analysis of facts and an international coverage of the local successes of that regime remained marginal and, as a result, the reputation of deregulated regimes remained bad or - at best - a contentious issue. The rush for competitive tendering was further stimulated by the European Commission’s endeavour to enact a Regulation that put forward competitive tendering of exclusive contracts as the preferred way to organise local public transport markets. Yet, as discussed in this workshop, deregulation in various guises may well play a growing role in local and regional transport. This is already visible in long-distance coach transport and in (international) European railway markets as from 2010. The workshop paper discusses whether such competition-based institutional alternatives to competitive tendering can provide efficiency and service improvements, how such competition-based alternatives should be ‘regulated’ and, alternatively, how a non-competitive direct award could perhaps still guarantee good performance. 相似文献