交通运输与物流专业英语Unite中英文

Unit Six Alternative Evaluation and Choice Text A Feasibility determinationEvery decision involves at least two options. Even though a single proposal was presented, decision makers have a choice between the proposal and doing nothing. Evaluation appraises the positive impacts and the negative impacts of alternative options in terms of either a single or multiple decision criteria. Determining relevant impacts to particular decision and specifying the appropriate decision criteria are related to the value system within which the choice is to be made. In the case of transportation decisions in the public sector, the operating value system is not that of any single individual or subgroup but that of the community as a whole. There exist conflicting value systems within society. Consequently, transportation decision also entails the resolution of conflicts.每一项抉择至少包含两个选项，即使是一个单一的提议，决策者也可以选择执行这个提议或什么也不做。

不管是根据单一的还是多样化的决策标准，评估的目的在于评价每个选项的积极影响和消极影响。

（人们）在做决定时，确立具体抉择的相关影响并详细说明合理的评判标准与其价值体系是相关联的。

在公共部门的交通决策中，其价值体系代表的不仅是某一个人或小团体的利益，而是整个社区的价值体系。

社会中常存在着相互冲突的价值体系，因此，交通决策也包含着解决（价值冲突）的问题。

Two types of evaluation studies are commonly undertaken: pre-implementation studies, which facilitate the choice of the best course of action from among several alternative proposals, and post-implementation studies, which assess the performance of already implemented action. Post-implementation studies are important for two reasons. First, they help to discover whether or not the implemented alternative performs well, and second, they help to determine whether or not it continues to perform properly over time. This is especially important in the case of transportation systems, which are subject to changing conditions and also to evolving goals and objectives. Continuous monitoring and periodic performance evaluation can help identify emerging problems and also provide guidance to the design of possible improvements.（交通决策中）通常存在着两种类型的评估调查：实施前调查，这有助于在几种备选方案中选出最佳方案；实施后调查，用于评估实施项目的各项性能指标。

实施后调查非常重要，原因有二：第一，它有助于发现实施项目是否运行良好；第二，它有助于确定（实施项目）随着时间流逝仍然能良好运行。

在易受条件、目标和目的改变影响的交通运输系统中，（实施后调查）显得尤为重要。

持续的监测和周期性的性能评估有助于发现问题，为可能的改进设计提供帮助。

An alternative must be both feasible and superior to all others in order to be selected for implementation. The prerequisites to the admission of an alternative to the list of acceptable options include the conditions of technological feasibility, economic efficiency, and cost-effectiveness, and availability of the needed resources. We present the fundamental elements of efficiency and effectiveness evaluation techniques, along with brief description of their conceptual foundations and their major strengths and weaknesses.用于实施的选择方案必须具有可行性且优于其他备选方案。

（项目中）能够进入候选名单的方案必须包括：技术可行性条件、经济效率、成本效率以及资源可得性。

我们举出了一些基础的与效率和有效性相关评估技术指标，简单地描述了它们的概念和各自的优缺点。

FeasibilityTechnological feasibility refers to the ability of a system to function according to the laws of nature and not to its desirability: A perpetual-motion machine may be highly desirable but technologically impossible. Engineers and other technologists are qualified to deal with questions relating to technology. Research and development are on-going activities that occasionally lead to technological breakthroughs. The vast majority of practical applications, however, involve the use of existing technology. Even then, innovative and creative ways of combining off-the-shelf technology are common. Consequently, the question of technological feasibility is an aspect of evaluation that cannot be ignored.技术可行性指的是在遵循自然规则的条件下系统能展现出的性能，它排除了不切实际的幻想，例如，人们都渴望（发明）永动机，但在技术上这是不可能做到的。

工程师和技术人员的职责在于处理与技术相关的问题，持续不断的研发偶尔能够实现技术上的突破，然而在大量的实践应用中使用的仍然是现存的技术。

尽管如此，将创新方法与现存技术相结合仍然普遍使用，因此，技术可行性问题是评估过程中不可忽视的一个方面EfficiencyEfficiency is defined as the ratio of the quantity produced (output) to the resources required for its production (input). Physical or machine efficiency is the ratio of the energy delivered by a machine or a process to the energy supplied to it. Although expressed in the same unit of measurement, the input and the output energy differ in form, for example, energy in the form of electricity vis-à-vis energy in the form of work done by the system. Machine efficiency is always less than unity because of the unavoidable energy losses that are incurred n the process. This waste can be justified only when the usefulness, or utility, of the output exceeds that of the input. When both the numerator and the denominator are converted to the same measure of economic value, their ratio is referred to as the economic efficiency of the machine, which must be greater than unity if the machine is to be economically feasible. The idea of economic efficiency has been extended to the evaluation of systems to contrast the economic value of the advantages (or benefits) that are derived from the system to its disadvantages (or costs).效率指的是产出量（输出）与生产所需资源（输入）之比。