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961.
This research examines the influence of traditional regulatory and voluntary approaches upon the willingness of marine facilities to address potential harms to water quality. Traditional regulatory approaches rely on enforcement of mandatory provisions while voluntary approaches use noncoercive means to engender voluntary actions to address potential harms within the context of broader laws. This research shows that mandatory regulations are not always necessary, but at the same time voluntary approaches are not always sufficient to motivate action. Given this, regulators need to consider the mix of approaches and other steps to achieve regulatory objectives. The latter include greater levels of information, technical assistance, and funding; stronger involvement of trade associations as conduits for information; and, in particular, the fostering of a collective sense of obligation to address potential harms.  相似文献   
962.

A trio of closely related land‐use/transport interaction models was developed using Marcial Echenique & Partners’ software package MEPLAN. The models were for the cities of Bilbao, (Spain), Dortmund (West Germany) and Leeds (England). All were calibrated using data drawn from earlier studies. The three models were used to predict the effects (relative to a base case) of a common programme of land‐use and transport policies or scenarios. This paper explains briefly the theoretical basis of the MEPLAN package as applied to urban models such as these three; describes the types of policies that have been assessed; and presents some of the key results.  相似文献   
963.
964.
Competing interests related to marine resources have the potential to create conflict in the coastal zone. In many parts of the world marine farms exist in close proximity to areas that support recreation and tourism. The purpose of this study was to examine residents’ perceptions of proposed marine farm development related to their proximity to, and recreational use of, a coastal area in New Zealand. Residents from two areas were surveyed about their recreational use of the region and about perceptions related to marine farm development. Results indicated that those living closest to proposed marine farms used the area more often and in different ways, were most sensitive to marine farm development, and were less positive in their evaluations of marine farms, despite agreeing that marine farms can have positive economic consequences for nearby communities. Implications for using stakeholder input for the planning and management of marine farms are discussed.  相似文献   
965.
Ján Mikolaj 《运输评论》2013,33(4):313-321
Traffic on the road network in Slovakia is increasing greatly, as a result of the country's location in central Europe. In recent years, transit truck traffic has exceeded the network's capacity causing many accidents, low vehicle speed and rapid degradation of the pavement. To deal with this situation a Road Network Management System (RNMS) has been developed. This system is based on national standards that evaluate road parameters, characteristics, and traffic levels and on new methods that consider the environmental impact and methods based on international standards (HDM III). Using these, the RNMS was developed as one homogeneous unit, not only in terms of its capacity, traffic level and economic efficiency, but also to evaluate individual sections, to optimize action, and prepare a rehabilitation budget. It took only five years to develop the RNMS because Slovakia has much relevant experience based on high level research in highway design, structural pavement design and material engineering.  相似文献   
966.

A transport system has been proposed using buses operating over ordinary roads and over special reserved tracks (busways) on which they might be automatically guided. Using cost and performance data resulting from an earlier technical study (not reported here), a hypothetical network of routes and services in the West Midlands conurbation is studied. Estimates of patronage diverted from public and private transport enable the profitability of the system and its costs and benefits to be assessed. It is concluded that the system could be attractive both in commercial and in cost/benefit terms, providing acceptable means could be found for handling the buses around and through the inner central areas of cities. The net environmental changes, which would result from additional fixed plant permitting more efficient use of mobile plant, have not been quantified.  相似文献   
967.
Canada’s west coast has been a hotspot of environmental conflict, most recently in defense of climate action and natural places under threat by energy development. This study examined sense of place as a source of tension in conflicts sparked by two energy proposals. The Bute Inlet run-of-river hydroelectric project would power British Columbia’s remote Central Coast, and the Trans Mountain pipeline expansion would transport bitumen from Alberta’s oil sands to tankers for export. Surveys, interviews, and mapping were used to investigate the depth and character of participants’ sense of favorite places and places expected to be affected by the projects, with appreciation, concern, and responsibility for nature as organizing themes. We discovered a regional, nature-centric sense of place on the south coast, and a sense of place among Albertans linked to that province’s oil and gas economy and its reputation as Canada’s chief breadwinner. Ties to natural places were found to underpin environmental advocacy by tapping into deep place connections as well as place connections conveyed through network ideologies and the protests themselves. We outline for consideration key characteristics of a regional sense of place, and offer ways to mitigate place-based economy versus environment conflicts.  相似文献   
968.

The advent of express coach bus lines offering guaranteed seating and emphasizing curbside pickup and drop-off is contributing to a revival in intercity bus travel in the United States. Relatively little is known, however, about the scale and geographic scope of these carriers or the competitive landscape in which they operate. To fill this void, this study evaluates the service networks operated by the two largest express coach operators in the country, BoltBus and Megabus, and evaluates a data set of 4775 fares sold on megabus.com. The results show that these carriers cumulatively serve 127 intercity segments and operate about 52.9 million bus miles per year. Together, these carriers have grown to about one third of the size of Amtrak, with Megabus and BoltBus providing 3.3 billion and .69 billion seat miles of service, respectively, compared to Amtrak’s 12.8 billion. With respect to the types of routes it serves and the competition it faces, Megabus has evolved into a carrier quite different than Boltbus; more than one third of Megabus’ bus miles are operated on segments without Amtrak service, while virtually all of BoltBus’ miles face this competition. The analysis of Megabus’ pricing shows that fares rise modestly within 2 weeks of departure, while the per-mile costs are much less ($.08/mile) for 300–399 mile trips than for those 50–99 miles ($.22/mile). Nevertheless, the dispersion of fares tends to fall as the departure date nears, regardless of distance. Together, these prominent bus lines serve 66 of the 100 most heavily traveled U.S. city pairs that have characteristics suitable for intercity bus service—which is more than Amtrak. With further growth on the horizon, planners, federal regulators, and researchers should collaborate on establishing reporting requirements for this expanding sector.

  相似文献   
969.
Transportation - Practitioners often use demand models to predict how neighborhood-level land use, infrastructure, demographic, and other changes may impact transportation systems. Few of the...  相似文献   
970.
文章以南昌地铁2号线雅苑路站施工为例,基于小应变硬化土体(HSS)本构模型,建立从端头井始发的双线盾构隧道掘进模型,分析了基坑开挖与双线盾构掘进共同作用下的土体沉降规律。结果表明:(1)加固盾构始发区土体可有效减弱区域范围内地表沉降,该区域内地表沉降量远小于区间隧道沉降量;(2)在同一埋深条件下,先建隧道地表沉降最大值高于后建隧道地表沉降最大值,地表横向沉降槽呈现非对称W型;(3)基坑开挖与盾构掘进共同作用下引起的地表沉降值,可以由二者单独作用产生的沉降值叠加计算得到。  相似文献   
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