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1.
The analytic hierarchy process has been used to elicit the knowledge of maritime transport stakeholders, such as seafarers, authorities, insurers and academics, regarding human factors and risk-reducing measures for ship groundings. Measures against human fatigue, alcohol abuse, language barriers, poor bridge management and safety climate have been compared with regard to costs and benefits. The measures are discussed in the context of large ships on a voyage of at least 24 h containing Bridge Resource Management. The study shows that stakeholders consider the costs of the measures to reduce human fatigue at sea surpass the benefits. Measures against alcohol abuse are regarded as the most cost–benefit efficient. Also, the stakeholders consider the watch scheme 8–4–4–8 to be less fatiguing than the 12–12 watch scheme. In addition, the results of the study support previous findings that inadequate manning levels contribute the most to human fatigue within the bridge management team.  相似文献   

2.
According to the mid-term review of the EU White Paper on Transport, Short Sea Shipping (SSS) is expected to grow at a rate of 59% (metric tonnes) between 2000 and 2020. If we consider that the overall expected increase in both freight exchanges and volume is 50%, sea transport is one of the most feasible alternatives to reduce traffic congestion on European roads. Maritime transportation may compete with road transport as far as certain traffics are concerned, but only when assuming external costs. This paper analyzes several intermodal transport chains involving a sea leg by comparing the effect of pollutant emissions from different ship types and road transport in terms of potential external cost savings. The translation of these emissions into environmental costs shows, for certain conditions, savings in the case of sea transport that would justify the use of an environmental bonus to promote the sea option.  相似文献   

3.
Land use/transport models and economic assessment   总被引:1,自引:0,他引:1  
This paper discusses the economic assessment of policies using land use/transport models. It argues that conventional forms of assessment focussing only on transport changes can underestimate the economic benefits of a policy. The paper argues that the benefits need to be measured by the changes of prices at the end of a trip and not just by the changes in travel costs. Models that do not estimate the changes of prices at the end of a trip cannot properly assess the impact of a policy.The model used in this paper is based on the MEPLAN software and estimates the location of households and employment and the interaction between them. It also estimates the cost of living for households and the production costs for employment. With these costs, it is possible to calculate the wider economic benefits beyond transport.The paper illustrates the assessment of policies for the Cambridge sub-region involving investment in public transport, orbital highway and congestion charging policies. The results forecast by the model are assessed in terms of the conventional cost-benefit using traveller’s surplus as benefits and compared with a wider assessment measure of compensation variation. It demonstrates that the last measure encompasses the wider benefits associated with transport policies which are not taken into account in conventional cost-benefit analysis.  相似文献   

4.
Current naval shipowners are being forced to extend the service lives of their aging vessels from budgetary and political constraints. This is causing them to incur significant costs due to maintaining the structure of these older ships to keep the ships in operation. These increasing costs make it desirable to design new naval structures with their minimization in mind, as well as ensuring that such vessels are robust to changes in expected service life with respect to their total lifetime cost. However, such structures will necessarily have higher production costs, therefore, an optimization framework is presented to estimate both production and maintenance costs for a naval vessel's internal structure and develop trade-spaces between these two competing objectives in order to find designs that represent a balance of both.  相似文献   

5.
China’s Belt and Road (BR) initiative is expected to facilitate international trade between the countries involved. In this study, we review the special requirements of wine logistics and the market growth potential of wine consumption in China. A model minimizing generalized logistical costs is developed and applied to wine imports in China, so that the best candidate cities in which to locate transport gateways and distribution centers can be identified. Our analysis suggests that the most preferred gateways are Shanghai, Tianjin, Guangzhou, and Hong Kong, which all have similar delivery costs. In comparison, Beijing and Chongqing have much higher delivery costs, mainly because they do not have good access to marine transport and/or efficient domestic distribution networks. For long-distance intercontinental transport of large volumes of wine, marine shipping remains the only viable delivery mode. However, wine distribution within China extensively uses air, road, and water transport. Therefore, cities with excellent multi-modal transport services are better positioned to become wine logistics gateways. Our study also highlights the importance of value-added services and good government support, which are important factors that influence distribution costs and quality.  相似文献   

6.
船体结构腐蚀模型对检测及维修规划的影响   总被引:1,自引:0,他引:1  
提出了基于风险的船体结构腐蚀优化检测及维修的基本理论框架.最优的检测及维修,是在保证结构在设计工作寿命内的可靠指标大于最低可靠指标的基础上,使结构生命周期内总的期望费用最小.建立了检测、维修及失效事件的安全余量方程,推导了失效及维修概率的计算公式.在此基础上,以船体结构两种常用的腐蚀模型Paik模型和Guedes Soares模型为例,分析了两种模型对最优检测及维修策略的影响.其结果表明,腐蚀模型对最优的检测及维修次数和时间有明显的影响,但是对总的期望费用及失效概率影响不大,而且两种腐蚀模型得出的最优失效概率都是10-3.  相似文献   

7.
Although counteracting environmental programmes and policies have been strengthened, large oil spills still occur at irregular intervals. The total oil spill costs and their compensations have attracted much interest from various parties, such as local stakeholders, and state and federal governments. This paper addresses five major cost categories whose aggregations are expected to cover the overall direct and indirect costs after the release of an oil spill. Among them, research costs should not be neglected, since they tend to be high if public attention has been drawn to the case. Through an examination of the relationship between the total oil spill costs and their admissible claims, we found that:
  1. admissible claims do not cover the overall costs of the oil spill, and
  2. admissible claims cannot be compensated in full in the case of large spills.
Clearly, a sound oil spill contingency management aims to minimize both the environmental impacts of areas most at risk and the total oil spill costs. In this paper an economic model for measuring environmental damages following an oil spill is addressed and applied to the Prestige case which happened to be the worst oil pollution in the history of Spain. The model indicates how an ideally a priori economic evaluation may intuitively help managers to make informed as well as fast decisions in contingency cases.  相似文献   

8.
Tidal waiting (for random arrivals and a sinusoidal tide pattern) can be approximated by simple formulae. Such formulae may be useful for estimating the benefits of dredging programmes carried out to reduce tidal waiting. Even if no economies of size are expected, a dredging programme may still be justified by time savings as they are especially imporatant for the larger and most time-expensive vessels.  相似文献   

9.
Although counteracting environmental programmes and policies have been strengthened, large oil spills still occur at irregular intervals. The total oil spill costs and their compensations have attracted much interest from various parties, such as local stakeholders, and state and federal governments. This paper addresses five major cost categories whose aggregations are expected to cover the overall direct and indirect costs after the release of an oil spill. Among them, research costs should not be neglected, since they tend to be high if public attention has been drawn to the case. Through an examination of the relationship between the total oil spill costs and their admissible claims, we found that:
  1. admissible claims do not cover the overall costs of the oil spill, and

  2. admissible claims cannot be compensated in full in the case of large spills.

Clearly, a sound oil spill contingency management aims to minimize both the environmental impacts of areas most at risk and the total oil spill costs. In this paper an economic model for measuring environmental damages following an oil spill is addressed and applied to the Prestige case which happened to be the worst oil pollution in the history of Spain. The model indicates how an ideally a priori economic evaluation may intuitively help managers to make informed as well as fast decisions in contingency cases.  相似文献   

10.
Beach “nourishment” consists of placing sand on an eroding beach. The widened beach provides increased storm protection to adjacent structures and improved recreational benefits, but is most often transient, requiring on-going, repeated nourishment episodes. Numerical models of beach nourishment typically address such questions as how long a widened beach will last; economic models compare the benefits and costs of preserving a stretch of beach without regard to its geomorphic evolution. Neither have addressed the physical nor economic interactions between adjacent nourishing communities. Here, we couple a numerical model of coastline evolution and a cost-benefit model of beach nourishment, allowing adjacent communities to make dynamic nourishment decisions. Beach nourishment benefits adjacent communities both “updrift” and “downdrift.” The total amount of money spent on nourishment activities can decrease by as much as 25% when adjacent communities both conduct on-going nourishment projects, as opposed to the case where each community nourishes in isolation.  相似文献   

11.
为应对大规模海上溢油污染,提高清污效率,提出了用双体船做清污船,并在两船之间安装清污装置的建议,供大家参考。  相似文献   

12.
Economic assessment of universally designed transport projects has not been studied in depth in the transport planning literature. Universal Design (UD) refers to the design of transport systems in a way that they are accessible to all users, irrespective of the users’ abilities. This definition of UD has not yet gained roots in the transport economic literature. The conventional thinking is that UD is for the few, i.e., the impaired, and given that they are few in numbers, UD projects will generally be unprofitable from a socioeconomic point of view because benefits will be low while investment costs will be too high. The objective of this paper is to prove the opposite: UD projects benefit all users of the facility, whether impaired or not, and the additional costs of implementing them are generally low; hence, their net present values are high and positive. We build on collaborative work between the Norwegian Public Roads Administration (NPRA) and the Institute of Transport Economics (TOI) aimed at creating guidelines for assessing the economic merits of UD projects. Therefore, in this paper, we: (1) define how UD is to be understood in the context of road and public transport; (2) describe the types of benefits and costs that accrue to users if UD projects are implemented; (3) address how the benefits and cost can be valued in monetary terms; and (4) using three different types of projects, demonstrate that UD projects are surprisingly profitable from a socioeconomic point of view. Finally, we address the implications of our findings and explain why governments need to be concerned with UD of transport systems.  相似文献   

13.
Rationality is an ideal for transport safety policy. As developed within normative welfare economics, rationality denotes the efficient use of safety measures based on cost–benefit analyses that include all relevant impacts of the measures. Efficiency in the technical sense of the term provides a perfectly clear and precise guideline for policy priorities. Nevertheless, some choices that are guided by cost–benefit analysis may strike us as paradoxical or counterintuitive. A paradox of rationality refers to any situation in which conflicting choices can both be defended as rational. This paper discusses a number of choices that may seem paradoxical. The first involves the choice between options that have identical impacts on safety, but in which these impacts are valued differently. The second deals with the tendency for preference reversals to occur when preferences for the provision of safety are aggregated. The third discusses the inability of conventional measures of willingness-to-pay to reflect the intensity of preferences. The fourth concerns the tendency for policy choice to favour the rich at the expense of the poor when willingness-to-pay is not adjusted for the marginal utility of money. A fifth situation refers to the fact that a policy option that looks attractive ex ante may fail an ex post compensation test because utility functions depend on health state. There is a potential conflict between individual and collective rationality with respect to the costs and benefits of some road safety measures. When developing a road safety programme, a set of road safety measures whose benefits exceed the costs when considered as stand-alone measures could have benefits smaller than cost when combined in a programme consisting of all the measures. Finally, there is a potential conflict between efficiency and negotiated consensus as mechanisms of resource allocation in the public sector. The sources of the paradoxes and ways of avoiding them are discussed. Some of the paradoxes can be avoided if changes in risk are valued in terms of a fixed price per unit of risk rather than according to a non-linear demand function.  相似文献   

14.
The 1998 White Paper proposed integration as the solution to Great Britain’s land transport problems. Most commentators agree that this much vaunted New Deal for Transport has been a failure. Yet some ten years later policy papers from bodies such as the Institution of Civil Engineers and the Centre for Cities are still proposing integration as a possible panacea.There are a number of reasons for the failure of integrated transport over the last decade. The first is the failure to define the concept. The second is the failure to operationalise the concept. The third is the lack of an evidence base on the success of integrated transport policies. Evidence is now emerging in Britain on the benefits (and indeed the costs) of some aspects of integrated transport policies. The fourth, and perhaps the most crucial, is the lack of will in terms of politicians, civil servants and the public at large, to adopt the behavioural changes necessary for an integrated transport policy to be successful. A series of organisational and funding changes are proposed that could advance the prospects for integration.  相似文献   

15.
为了满足环保对造船厂VOCs排放总量的限制,并实现降低涂装制造成本降低之目的,如何减少油漆使用总量成为了一条关键探索路径.扫砂作业模式的推广正是打通这一路径的最有效方式之一.通过对分段扫砂与冲砂作业模式的深入对比研究,总结出扫砂作业模式所特有的经济效益,并提供了一套建立扫砂作业基准的基本程序.  相似文献   

16.
Options-Based Multi-Objective Evaluation of Product Platforms   总被引:1,自引:0,他引:1  
A platform is the set of elements and interfaces that are common to a family of products. Design teams must choose among feasible platform concepts upon which a product family could be based, often involving new technologies. Multiple performance objectives need to be considered. A standard approach is to convert the performance outcomes into financial figures, which can then be weighed against the required investments. However, it is not always possible to transform performance outcomes (benefits) into monetary terms, such as in defense or highly technical projects. A multi-objective form of real-options-based platform selection is developed. Systems are compared based on multiple technical and economic goals, incorporating uncertainty by representing the unknown factors during the subsequent development process with probability distributions. The range of uncertain outcomes is integrated into single expected measures of effectiveness, which can then be applied to select the most appropriate platform and set of support product variants. An application to the design of platform-based families of naval high-speed ships is shown.  相似文献   

17.
Government recently introduced the Transport Law Reform Bill, which if passed by Parliament, will allow foreign vessels to uplift and discharge cargoes and passengers along the coast of New Zealand. Coastal shipping is part of the domestic transport industry, which has benefitted from deregulation and considerable restructuring over the last decade. This paper provides a brief review of the coastal shipping industry in New Zealand and an overview of international cabotage laws. An alternative open coast shipping policy proposed by the New Zealand Shipping Federation, which is based on ‘level playing fields’ principles, is presented. The scope of cost benefit analysis is outlined and the potential costs and the potential costs and benefits of the Government's open coast shipping policy are summarized. Despite the potential costs to New Zealand of an open coast policy appearing to be considerably greater than the potential benefits. Government officials have not undertaken an empirical cost benefit analysis. The paperr concludes that hte clauses of the Transport Law Reform Bill relating to an open coast policy should be withdrawn and a full empirical cost benefit analysis should be undertaken to determine the best coastal shipping policy for New Zealand.  相似文献   

18.
We estimate the cost over the next 50 years of allowing Delaware's ocean beaches to retreat inland. Since most of the costs are expected to be land and capital loss, especially in housing, we focus our attention on measuring that value. We use a hedonic price regression to estimate the value of land and structures in the region using a data set on recent housing sales. Then, using historical rates of erosion along the coast and an inventory of all housing and commercial structures in the threatened coastal area, we predict the value of the land and capital loss assuming that beaches migrate inland at these historic rates. We purge the losses of any amenity values due to proximity to the coast, because these are merely transferred to properties further inland. If erosion rates remain at historic levels, our estimate of the cost of retreat over the next 50 years in present value terms is about $291 million (2000$). The number rises if we assume higher rates of erosion. We compare these estimates to the current costs of nourishing beaches and conclude that nourishment make economic sense, at least over this time period.  相似文献   

19.
抗冰海洋平台的全寿命优化设计I-理论与模型   总被引:1,自引:1,他引:0  
文章基于投资—效益准则,建立了抗冰平台全寿命总费用最小的优化设计模型;考虑了多种类型的性能要求(结构、设备、人员),并建立了相关判据;提出了包括结构的初始费用、维修费用和期望损失费用的冰区海洋平台全寿命总费用评估模型;提出了平台结构主要功能的确定及描述方法、相应的功能失效损失值估计模型。  相似文献   

20.
为科学评价长江南京以下12. 5 m深水航道二期工程的实施效果,通过运输经济模型、投入产出法、重力模型等研究方法,全面分析工程的经济、社会、宏观、环境效益。结果表明,长江南京以下12. 5 m深水航道工程实施以来,已经取得了显著降低物流成本、带动区域经济增长、新增就业岗位、拉动财政收入增长、促进沿江地区节能减排等实际效益,工程的战略意义得到充分体现。  相似文献   

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