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141.
142.
Nakul Sathaye Robert Harley Samer Madanat 《Transportation Research Part A: Policy and Practice》2010,44(8):642-659
In recent years, the reduction of freight vehicle trips during peak hours has been a common policy goal. To this end, policies have been implemented to shift logistics operations to nighttime hours. The purpose of such policies has generally been to mitigate congestion and environmental impacts. However, the atmospheric boundary layer is generally more stable during the night than the day. Consequently, shifting logistics operations to the night may increase 24-h average concentrations of diesel exhaust pollutants in many locations. This paper presents realistic scenarios for two California cities, which provide diesel exhaust concentration and human intake estimates after temporal redistributions of daily logistics operations. Estimates are made for multiple redistribution patterns, including from 07:00–19:00 to 19:00–07:00, similar to daytime congestion charging polices, and from 03:00–18:00 to 18:00–03:00, corresponding to the PierPASS program at the ports of Los Angeles and Long Beach. Results for these two redistribution scenarios indicate that 24-h average exhaust concentrations would increase at most locations in California, and daily human intake is likely to worsen or be unimproved at best. These results are shown to be worse for inland than coastal settings, due to differences in meteorology. Traffic congestion effects are considered, using a new graphical method, which depicts how off-peak policies can be environmentally improving or damaging, depending on traffic speeds and meteorology. 相似文献
143.
Injuries to natural resources from the release of hazardous substances into aquatic environments have led to hundreds of millions of dollars in compensatory damages awarded under the Comprehensive Environmental Response, Compensation and Liability Act (CERCLA) and other legislation. The institutional mechanisms for negotiating and carrying out the terms of CERCLA natural resource settlements are still in their infancy, and each case has a unique set of injuries, assigned damages, payout schedules, trustee council membership and operating procedures, and environmental conditions and constraints. One of the settlements that has made significant progress toward large‐scale habitat enhancement has occurred in Elliott Bay, a busy, seriously impacted urban harbor in Washington State. The Elliott Bay case is unique among natural resource injury settlements because of the active involvement of two local governments, the City of Seattle, and Metro, who were named as defendants in a lawsuit brought by the National Oceanic and Atmospheric Administration (NOAA) on behalf of the natural resource trustees of Elliott Bay. Both local governments have maintained, and continue to operate, outfalls that discharge into Elliott Bay, and both entities were subject to attempts to recover damages under CERCLA. Following the filing of the lawsuit over injuries to the natural resources of the estuary, alleged to have resulted from the operation of these outfalls, the parties involved negotiated a consent decree settlement. The Elliott Bay/Duwamish Restoration Program has established a process to redress some of the injuries that were attributed to the operation of these outfalls. 相似文献
144.
Abstract local wastewater management policies can be important tools for protecting marine water quality when coordinated with sound land use and environmental planning. that relationship is examined through a review of the point and nonpoint source pollution issues associated with centralized versus decentralized wastewater management approaches, sewerage extension and plant expansion effects, and sewerage management practices. we use information provided by 161 local jurisdictions in coastal regions of the southeastern united states and various secondary regions of the southeastern united states and various secondary sources. the article concludes with a discussion of policy implications and recommendations to improve the coordination of local sewerage extension/expansion practices and land use planning. 相似文献
145.
Robert J. McCalla 《Maritime Policy and Management》2013,40(4):279-293
The administration, management and development of ports in Canada is a Federal government responsibility. This centralist control of ports has been the subject of criticism by many for a variety of reasons, not the least of which is that it is not responsive enough to the affairs of the local level. This problem, along with others, has resulted in the introduction in the Canadian Parliament of proposed legislation over the past five years to alter port administration and development in Canada. The proposals culminated in the recent passage of the Canada Ports Corporation Act which, among other things, will see the abolition of the National Harbours Board. A review of the administrative structure the new Act replaces, along with a review and assessment of the Act itself and the proposed legislation which predated it, forms the basis of this paper. It will be seen that because of the new Act the centralist approach to port administration is maintained, but greater local autonomy and financial self-sufficiency will also be available to ports. However, the central administration will still have the problem of co-ordinating the development of Canadian ports, since ports will continue to be constituted under at least four different pieces of legislation. 相似文献
146.
Abstract Designing environmental monitoring programs to deal with widespread, subtle, and/or cumulative impacts on a regional basis is challenging. It requires a shift away from focusing primarily on individual point sources to a more regional perspective. It also necessitates involving scientists and managers together in a cooperative effort to establish priorities and articulate clear objectives. In our view, this objective‐setting task is neither a strictly scientific nor a strictly management activity. It depends on effective communication between scientists and managers but is confounded by differing perspectives, value systems, and behaviors. We present a conceptual framework to assist managers and scientists in this process. This is intended to structure such communication by helping to create a context that permits fruitful give‐and‐take between the two groups. We then describe a six‐part model for specifying the key elements of regional monitoring objectives. 相似文献
147.
Robert L. Stokes 《Coastal management》2013,41(1):113-114
The Cost of Environmental Protection: Regulating Housing in the Coastal Zone by Dan K. Richardson. Published by the Center for Urban Policy Research Rutgers University, 1976. 250 pp., $10.00. 相似文献
148.
The insufficiency of infrastructure capacity in an air transport system is usually blamed for poor punctuality performance when implementing flight schedules. However, investigations have revealed that ground operations of airlines have become the second major cause of flight delay at airports. A stochastic approach is used in this paper to model the operation of aircraft turnaround and the departure punctuality of a turnaround aircraft at an airport. The aircraft turnaround model is then used to investigate the punctuality problem of turnaround aircraft. Model results reveal that the departure punctuality of a turnaround aircraft is influenced by the length of scheduled turnaround time, the arrival punctuality of inbound aircraft as well as the operational efficiency of aircraft ground services. The aircraft turnaround model proposed is then employed to evaluate the endogenous schedule punctuality of two turnaround aircraft. Model results, when compared with observation data, show that the operational efficiency of aircraft ground services varies among turnarounds. Hence, it is recommended that the improvement of departure punctuality of turnaround aircraft may be achieved from two approaches: airline scheduling control and the management of operational efficiency of aircraft ground services. 相似文献
149.
Brenda M. Katon Robert S. Pomeroy Len R. Garces Marshall W. Ring 《Coastal management》2013,41(1):29-37
The local management of mangrove resources in Cogtong Bay, Philippines, dates back to the 1940s and 1950s when some families informally designated mangrove areas under their care and management. The 1960s and 1970s saw several exogenous events that led to the progressive denudation of mangrove stands and the decline in fish catch per fishing trip. This article draws attention to the forces that prompted coastal villages and external agents to collaborate with the national and local government units in resource rehabilitation. It also assesses the performance of a coastal resources comanagement project at Cogtong Bay. 相似文献
150.