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111.
There is growing interest in establishing additional evidence, under the umbrella of the wider economy impacts of transport infrastructure projects, to support transport projects in general and public transport projects in particular that struggle to obtain benefit–cost ratios sufficient to gain the support of financial agencies. This paper focuses on one element of wider economy impacts, often referred to as effective economic (employment) density or employment agglomeration impacts, and another, less usually identified, social accessibility impact (SAI) which we refer to as effective social density, which in broad terms provide, correspondingly, evidence of the potential gains in work-related output (often referred to as productivity gains) and potential gains in non-work-related outputs. Both are associated with gains in individual and household benefit attributable to improved accessibility to services linked with populations and particular locations. The SAIs may capture some of the induced benefits in those jurisdictions where these are included routinely in benefit–cost analysis, and the methodology here is most appropriate to those settings where an existing calibrated demand curve may not be available. Using the proposed high speed rail (HSR) project between Sydney and Melbourne as the empirical setting, we identify economic agglomeration and social accessibility benefits for work and non-work related activity respectively. We find the former to be relatively small compared to the significant gains associated with non-work related travel activity, suggesting the greatest benefits associated with HSR, especially for those residents outside of the major metropolitan areas, will be non-work related travel activity. 相似文献
112.
113.
David A. Hensher 《Transportation Research Part B: Methodological》1985,19(4):303-313
Vehicle-use modelling at the household level has taken on new importance with the pressures on governments to encourage more efficient utilisation of increasingly scarce nonreplenishible liquid fuels. The fundamental energy equation recognizes two direct influences on consumption—the fuel efficiency of the vehicle and the amount of use. Until recently, the interrelationship between vehicle choice and vehicle utilisation at the household level was acknowledged but ignored. The availability of reliable vehicle-use data at the household level now enables a more serious effort at amending the imbalance of research effort where the reliance has been predominantly on vehicle choice modelling and gross (exogenous) assumptions on utilisation as a basis for predicting fuel consumption. This paper proposes an econometric method for identifying the influences on household vehicle use. It differs from previous empirical work in that vehicle kilometers, fuel cost per kilometer and vehicle fuel efficiency are endogenous, with utilisation of each vehicle endogeneously dependent on the utilisation of each and every household vehicle. The data are drawn from wave 1 of a four-wave panel of 1436 households in the Sydney metropolitan area. The empirical findings expose a set of influences on use hitherto not considered. The model specification provides an appropriate module for integration with household-based discrete choice models of vehicle choice. 相似文献
114.
Contained herein are the results of research which quantifies the effects that various existing and projected truck configurations have as live loadings upon bridges which currently exist on the National Bridge Inventory (NBI). The truck configurations were determined from those actual or proposed vehicles which exhibit the highest GVW and which either are causing or are perceived to cause the highest levels of overstress on bridge superstructure elements. In order to simulate most accurately the actual field conditions, a criterion was defined which contained three major requirements: 1) The bridges utilized within the study shall be defined as being a statistically significant sample and be actual bridges taken from the NBI; 2) The analysis method shall be consistent with those actually used by engineers in designing and rating bridges, and; 3) The criteria utilized in evaluating the various bridge structures under the defined loadings shall be consistent with current practices. The results obtained indicates the acceptability of various truck configurations by GVW, size, and axle deployments, by system for the different criteria now in use. 相似文献
115.
116.
SCUBA diving is an increasingly popular activity that provides a number of benefits to coastal communities. However, the sustainability of recreational diving on coral reefs is largely dependent on the health of reef ecosystems. Divers can minimize their impacts to coral reefs through responsible diving behaviors, which are in part guided by social norms. The behavioral obligation and sanction components of twelve diving behaviors were determined for Florida Keys divers throughout the course of a year. Recognizing that recreationists are not homogenous, these norms were compared according to diver specialization level. Specialized divers felt a stronger obligation not to touch corals and to pick up garbage from the sea floor than did less specialized divers. Specialized divers also reported they would feel greater embarrassment for losing buoyancy control, touching corals, taking pieces of dead corals, or touching marine mammals. The findings point to a connection between specialization level and social norms, and a relationship to ensuring continued reef health. 相似文献
117.
The exceptional growth of whalewatching in Baja California Sur (BCS) and other parts of Mexico during the last 10 years motivated the design and implementation of a Mexican whalewatching law based on experiences in BCS. However, recent research in the Ensenada whalewatching area confirms that this law is insufficient in this area because whalewatching boats and other fishing, cruising, or drifting boats influence the behavior (swimming direction and velocity) of migrating gray whales. In the long term, the migration corridor might be displaced offshore, and whalewatching may become infeasible. This study proposes a management planning process to adapt regulations to this area, to promote adherence to regulations by encouraging self-regulation and strengthening law enforcement, and to enhance the tourist service on board. The actors involved were identified. 相似文献
118.
David Cockroft 《Maritime Policy and Management》2013,40(3):195-196
Organizational Effectiveness (OE) is a rather new concept in the port business literature and not widely studied before. From the systems perspective, this concept focuses on the goals of the organization, the resources needed to achieve these goals, and the relationship between the organization and its environment. The reason behind choosing a systems approach is the significant role of seaports as open systems affected by changes and developments in world trade, supply chain and logistics trends, maritime transport, and technological developments. While seaports are multi-faceted organizations that constitute different interdependent and integrated units in their structure, they can also be regarded as the subsystems of the supply chain system. As being the social and technical systems, port organizations have unique characteristics that should be examined in detail to assess their effectiveness. To assess the effectiveness of port organizations, principally a set of effectiveness measures applicable to seaports should be determined. The main aim of this study is to assess the relative importance of the main effectiveness criteria in seaports and to determine the significance of main inputs and port subsystems which can be referred as the means to achieve effectiveness. By using the systems approach, the inputs, the processes, and the outputs of the port organizations are clearly defined with a conceptual model. Thirty-three statements have been developed under the main categories in the systems model and a two-round delphi survey is conducted, and qualitative analysis of the experts’ opinions is carried out. The results of the delphi survey show that the main port inputs are port infrastructure, equipments, technology, and port labor; the major port processes are ship and cargo operations together with the logistics services, safety and security, information technologies, and marketing; and the most important effectiveness measures for the seaports are productivity, efficiency, service quality, adaptability, information and communication management, profitability, human resource quality, and customer satisfaction. 相似文献
119.
Various models for competition and ownership of urban rail systems have been used in South East Asia cities since the early 1990s. The paper reviews and classifies the approaches used in Bangkok, Kuala Lumpur, Manila and Singapore. The planning, financing, procurement, implementation and operation of these systems, and the institutional context for them, are examined. All of the systems that have used private sector finance for the development of the initial systems have faced financial problems. Optimism bias in demand forecasts and unrealistic expectations for cost recovery of capital intensive systems have been contributing factors. Lessons to be learned include the importance of clear government leadership and sound institutional arrangements, and the need for improved understanding of the best manner in which the private sector can be used to achieve efficient and effective rail projects. 相似文献
120.
The Ohio Department of Natural Resources and the U.S. Office of Coastal Zone Management have proposed the Old Woman Creek estuary on Lake Erie as the nation's first freshwater estuarine sanctuary. Designation as an estuarine sanctuary will preserve 637 acres of marshland, sand bar, a barrier beach, and surrounding forested uplands for public education and research. The original January 1975 grant application required modification following local residents’ objections to purchases of highly productive farmland and land‐use controls on a watershed‐wide buffer zone. A federal grant award was made in July 1977, with full acquisition anticipated by the end of 1978. 相似文献