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101.
Abstract

The implementation of catch share programs can have socio-economic and ecological benefits, yet may also change the distribution of those benefits within a fishery or across communities. Quota set-asides can mitigate the impacts of these changes. During the implementation of the West Coast groundfish trawl catch share program, 10% of the quota was set aside to be used toward five goals in the Adaptive Management Program (AMP). This quota was to serve as an insurance policy during the substantial changes that were expected to occur under the new management regime. However, this program has not yet been fully developed, in part due to delayed decision-making and the controversial nature of allocating quota. Here, we examine and score six policy options for the AMP against four criteria: effectiveness, flexibility, political viability, and implementability. While each of the options has strengths and weaknesses, those that ranked highly include allocating quota pounds (QP) via the status quo and via auction. Our results highlight the drawbacks of delaying contentious decisions, where uncertainty for participants can constrain operational decisions and subsequent economic gains. We demonstrate the utility of this decision-making framework for evaluating tradeoffs between alternatives, especially for a program with multiple, competing objectives.  相似文献   
102.
This paper discusses how a particular tool in the employment relationship has become part of a desirable transport future. We examine how and why the employee mobility budget has entered the set of sustainable transport measures in Belgium. In a discourse analysis, we examined 52 articles from newspapers, magazines as well as research reports. The main actors in the debate are identified using an exploratory social network analysis, and we discuss the various definitions of the employee mobility budget, the framing of the problems to be solved (in the first place congestion), and the main conflicts between actors. The results reveal the sustained efforts to put the idea on the agenda and the formation of a coalition of the willing. The fact that the mobility budget concept is highly compatible with the hegemonic discourse on employment relations contributes to its popularity. Finally, the individualisation of employment relations and the decrease in attention for environmental aspects are highlighted as potential threats of the type of sustainable mobility policy studied in this paper.  相似文献   
103.
With the help of automated fare collection systems in the metro network, more and more smart card (SC) data has been widely accumulated, which includes abundant information (i.e., Big Data). However, its inability to record passengers’ transfer information and factors affecting passengers’ travel behaviors (e.g., socio-demographics) limits further potential applications. In contrast, self-reported Revealed Preference (RP) data can be collected via questionnaire surveys to include those factors; however, its sample size is usually very small in comparison to SC data. The purpose of this study is to propose a new set of approaches of estimating metro passengers’ path choices by combining self-reported RP and SC data. These approaches have the following attractive features. The most important feature is to jointly estimate these two data sets based on a nested model structure with a balance parameter by accommodating different scales of the two data sets. The second feature is that a path choice model is built to incorporate stochastic travel time budget and latent individual risk-averse attitude toward travel time variations, where the former is derived from the latter and the latter is further represented based on a latent variable model with observed individual socio-demographics. The third feature is that an algorithm of combining the two types of data is developed by integrating an Expectation-Maximization algorithm and a nested logit model estimation method. The above-proposed approaches are examined based on data from Guangzhou Metro, China. The results show the superiority of combined data over single data source in terms of both estimation and forecasting performance.  相似文献   
104.
姜启平 《北方交通》2011,(11):76-78
公路工程概算编制是一项重要而复杂的工作,从概算编制的流程、编制时应注意的问题、编制完成后的复核三方面阐述了如何完善正式的概算文件。  相似文献   
105.
Road transportation is one of the major sources of greenhouse gas emissions. To reduce energy consumption and alleviate this environmental problem, this study aims to develop an eco-routing algorithm for navigation systems. Considering that both fuel consumption and travel time are important factors when planning a trip, the proposed routing algorithm finds a path that consumes the minimum amount of gasoline while ensuring that the travel time satisfies a specified travel time budget and an on-time arrival probability. We first develop link-based fuel consumption models based on vehicle dynamics, and then the Lagrangian-relaxation-based heuristic approach is proposed to efficiently solve this NP-hard problem. The performance of the proposed eco-routing strategy is verified in a large-scale network with real travel time and fuel consumption data. Specifically, a sensitivity analysis of fuel consumption reduction for travel demand and travel time buffer is discussed in our simulation study.  相似文献   
106.
Abstract

This paper provides a comprehensive review of travel-time budget (TTB) studies in the literature for about the past four decades. Starting with the concept of TTBs, it discusses both the studies that support the existence of TTB and also those that deem the concept to be unfounded. Sociodemographic variables and their relation to TTB are also discussed briefly. However, as past studies use different data sources, survey techniques, and methodology for analysis, cross comparison of studies is not possible. Most importantly, the underlying cause of the regularity that is found at an aggregate level is still not known. The idea of TTB is important because, if it exists, it would mean that the total time spent on travelling per person per day will remain unchanged in spite of all improvements to transport. TTB has immense implications for transport policies and it is usually ignored. The paper also explores the available theoretical explanation of this concept, past research gaps and new analysis potentials. Recent directions in TTB studies are also discussed together with the potential use of multiday multiyear panel data in TTB research to explore the phenomenon better than before.  相似文献   
107.
投标策略是投标人经营决策的组成部分,指导投标全过程。影响投标的因素十分复杂,既要考虑自身优势和劣势,也要考虑竞争的激烈程度,还要分析投标项目的整体特点。因此,需要投标人认真研读投标文件指标要求、风险类型、材料价差及报价方法,尤其是概预算定额的运用直接影响到投标报价。  相似文献   
108.
长山-红岗子段是珲春-乌兰浩特国家高速公路的一部分,本段主要围绕如何较多地、合理地利用原一级公路改建,并考虑避让文物保护区和减少对城镇干扰等因素进行方案比较,找出存在的问题.通过调查实际情况,考虑未来发展,提出科学处理方法,使项目在技术指标、安全设施、环境保护、概算等方面达到安全、经济、合理.  相似文献   
109.
通过对工程项目成本构成的深入分析,提出了成本预测、成本控制及降低工程成本的有效途径。  相似文献   
110.
介绍工程预算编制过程中应注意的几个问题,通过优化施工组织设计,加强施工技术规范以及定额分项等的熟悉程度,提高工程预算编制的速度及质量。  相似文献   
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