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Fixed-rail metro (or ‘subway’) infrastructure is generally unable to provide access to all parts of the city grid. Consequently, feeder bus lines are an integral component of urban mass transit systems. While passengers prefer a seamless transfer between these two distinct transportation services, each service’s operations are subject to a different set of factors that contribute to metro-bus transfer delay. Previous attempts to understand transfer delay were limited by the availability of tools to measure the time and cost associated with passengers’ transfer experience. This paper uses data from smart card systems, an emerging technology that automatically collects passenger trip data, to understand transfer delay. The primary objective of this study is to use smart card data to derive a reproducible methodology that isolates high priority transfer points between the metro system and its feeder-bus systems. The paper outlines a methodology to identify transfer transactions in the smart card dataset, estimate bus headways without the aid of geographic location information, estimate three components of the total transfer time (walking time, waiting time, and delay time), and isolate high-priority transfer pairs. The paper uses smart card data from Nanjing, China as a case study. The results isolate eight high priority metro-bus transfer pairs in the Nanjing metro system and finally, offers several targeted measures to improve transfer efficiency.  相似文献   
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Deviated fixed route transit (DFRT) service connecting rural and urban areas is a growing transportation mode in the USA. Little research has been done to develop frameworks for route design. A methodology to explore the most cost‐effective DFRT route is presented in this paper. The inputs include potential DFRT demand distribution and a road network. A heuristic is used to build possible routes by starting at urban cores and extending in all network directions in certain length increments. All the DFRT routes falling in the length range desired by the users are selected. The cost effectiveness of those routes, defined by operating cost per passenger trip, is compared. The most cost‐effective route is selected and presented in a GIS map. A case study illustrates the methodology in several Tennessee metropolitan regions. The most cost‐effective route length is case specific; some routes (e.g. those out of our Nashville case) are most cost effective when short, while others (e.g. those out of Memphis) are most cost effective when long. Government agencies could use the method to identify routes with the lowest operating cost per passenger given a route length or an operating cost budget. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
3.
Models of integrated management emphasize the role of the surrounding socioeconomic and political environment in influencing management choices for natural resources. In this study, we explore a model that examines the influence of socioeconomic and political variables on the wetland management programs of U.S. states. Logistic regression was used to identify environmental, socioeconomic, and political variables that explained variation in state wetland programs. The likelihood of strong planning, nonregulatory, regulatory, and overall programs increases as the importance of fisheries in the state increases (p < 0.05), but decreases as population density increases (p < 0.15). Furthermore, there is an increasing likelihood of stronger regulatory and overall programs as environmental group activity and industry importance increases (p < 0.05). These findings provide empirical evidence to support the contention that management approaches used in one state often must be adapted to fit the realities of another given state.  相似文献   
4.
A rather significant number of business entities already operate within (or, have considered to exploit) the Arctic region, focusing upon previously untapped resources such as precious minerals and large quantities of oil and gas; touristic and fishing activities are clearly on the rise, with various endeavors of maritime transport also being put forward. Up until recently, harsh year-long environmental conditions have significantly hindered the necessary access and transport connections in the Arctic. Even in the case that weather conditions did permit vessels’ passage, unreliable navigational aids and lack of infrastructure/support provided obstacles difficult to overcome. However, environmental data recorded during the last couple of decades clearly indicates that there is a continuous decline of ice coverage in the “High North.” Given this steady decline, the Arctic has now been viewed as a promising field for economic activities and is considered as a potential connecting corridor between Asia and Europe/America (and vice-versa). As human presence and operations are expected to intensify there, it is of utmost importance to evaluate the current level of support towards ships that will be crossing the region; capabilities in relation to search and rescue (SAR) operations and oil spill response are also important. The analysis in hand will first deliver a discussion of the so-called Arctic Passages. While various different maritime routes have been proposed in relation to the Arctic, the most promising one, the Northern Sea Route (NSR), will provide the epicenter of discussion. Through an extensive literature review that includes numerous internet resources, the current analysis will identify the numbers of icebreakers already operating in the NSR, as well as those that will be commissioned into service in the near future. The choice to research the specific type of vessels is supported by a simple argument: icebreakers currently are and will continue to be in the foreseeable future the main “tool” to support shipping activities in the Arctic. Furthermore, emergency management capabilities in the Russian Arctic will be examined to include the current state of rescue coordination centres along with the availability of SAR assets. Additionally, the efforts thus far by the Arctic Council to increase coordination and interaction among the States involved in Arctic affairs will be summarized; the latter will be achieved via a brief review of a very important legally binding agreement: the “search and rescue” instrument. In conclusion, the Russian State has already heavily invested in icebreakers’ building and their current number is fully capable to handle the present level of limited traffic. On the other hand, ships are currently faced with long distances to cross (often without adequate support) adverse environmental conditions, unpredictable hurdles, and slow response times in case of an emergency. Therefore, in case ships operating in the region are increased, it will be difficult to deal with all the additional demands for support. Of particular interest is the fact that considering the vast area of the NSR, the overall available response capabilities in the region under discussion are rather thin; any further increase of maritime traffic in the “High North” must be balanced with additional strengthening of emergency management capabilities. In any case, should the NSR become fully integrated in the global maritime transport system, Russia’s geopolitical status will be clearly improved and further research is needed to discuss the implications both at the regional and global levels.  相似文献   
5.
The potential of turboprops for reducing aviation fuel consumption   总被引:1,自引:0,他引:1  
To assist in aviation systems planning in the context of fuel price uncertainty and environmental regulation, we take a total logistics cost approach and evaluate three representative aircraft (narrow body, regional jet, and turboprop) for operating and passenger preference costs over a range of fuel prices. Homogenous fleets of each vehicle category are compared for operating and passenger costs over a range of fuel prices and route distances and the minimum cost fleet mix is determined. In general, as fuel prices increase, the turboprop offers a lower operating cost per seat over a wider range of distances when compared with both jet aircraft models. The inclusion of passenger costs along with operating costs decreases the number of fuel price and distance pairs where the turboprop exhibits the lower cost. This analysis shows that the aircraft that exhibits the lowest cost is highly sensitive to fuel prices and passenger costs and points to the important balance between saving fuel and serving passengers.  相似文献   
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