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151.
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   
152.
Book review     
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   
153.
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   
154.
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   
155.
Preface     
  相似文献   
156.
The Coastal Zone Management Effectiveness Study was undertaken between 1995 and 1997 to determine how well state coastal management programs in the United States were implementing five of the core objectives of the U.S. Coastal Zone Management Act (CZMA). The five core objectives studied were: (1) protection of estuaries and coastal wetlands; (2) protection of beaches, dunes, bluffs and rocky shores; (3) provision of public access to the shore; (4) revitalization of urban waterfronts; and (5) accommodation of seaport development (as an illustration of the policy to give priority to coastal-dependent uses). Separate articles in this issue of Coastal Management report the findings of the five studies, each dealing with one of the core objectives. Each of the articles assesses issue importance, processes and tools used, and the limited outcome data available for that objective. This article provides an overview of the purposes of the study, the methodology used, the summary findings of each study, and overall conclusions and recommendations of the study team. State coastal programs are found to be effective in addressing the five CZMA objectives examined, but this conclusion is based on very limited information about program outcomes. A more definitive conclusion will require better outcome information. Coastal managers in the United States have not agreed upon indicators of success, which severely inhibits systematic and sustained collection of outcome information. A national outcome monitoring and performance evaluation system is recommended to address these deficiencies and allow better determinations of program effectiveness in the future.  相似文献   
157.
Five coastal counties in Florida were studied to assess the effect of state-mandated local comprehensive plan policies on hurricane evacuation clearance times and public shelter demand. Numbers of residential units in 2002 and at the time of plan approval were estimated from property parcel data. Abbreviated transportation models were used to calculate 2002 evacuation times and shelter demand and to ascertain the impacts of post-plan residential growth within hurricane hazard areas. Calculated increases in clearance times and shelter demand are not in concert with the state's mandate to maintain or reduce clearance times. State law currently limits the leverage of the state planning agency to compel local governments to implement the required comprehensive plan policies. We recommend a concurrency management strategy that parallels the state's requirement to provide adequate transportation facilities to accommodate the impacts of future residential growth. Such a policy could be employed in other states as well.  相似文献   
158.
Abstract

This paper reports on research conducted in support of a coastal zone management effort to reduce erosion and sedimentation impacts in a wetland watershed, Elkhorn Slough, Monterey County, California. The research reviews methods of determining soil erosion susceptibility and relating it to land‐use intensity within the watershed, measured by a land disturbance index. Erosion susceptibility is measured in three ways: by a combination of slope and the erosion factor of the Universal Soil Loss Equation; by field measurement of erosion and deposition on selected sites; and by computer‐assisted terrain analysis of data from secondary sources. Land use is shown to be a more important factor than landform in influencing relative erosion susceptibility.  相似文献   
159.
Abstract

Practitioners play a critical yet largely unexamined role in translating collaborative, ecosystem-based management (EBM) for social-ecological systems from theory to practice. We paired mental models and social network analytical methods and applied them to two cases of marine EBM in Rhode Island and New York, focusing on practitioners themselves, to understand the relationship between practitioners’ mental models of marine ecosystems and the extent and nature of collaboration within each network. Mental models analysis was used to assess the comprehensiveness and balance of practitioners’ mental models, and social network analysis was used to assess the role and influence of practitioners within each network. A comparative statistical analysis was then performed to understand the relationship between mental models and network measures. Research revealed a statistically significant correlation between practitioners’ mental model comprehensiveness and practitioners’ influence within the network. In other words, practitioners with comprehensive mental models of the ecosystem for which they were planning were found to act as “brokers,” connecting those who were not otherwise connected, bridging jurisdictions, sectors, and disciplines. Results underscore the importance of brokers in achieving the collaborative and integrated goals of EBM and suggest the need for greater attention to practitioners’ role in EBM implementation.  相似文献   
160.
Specialization in cargoes and forelands is defined for the ports of Montreal, Quebec, Saint John, and Halifax using a variation of the location quotient. Economic impact is also defined using the location quotient. All ports are shown to have some degree of specialization; whereas, Saint John and Halifax have relatively greater economic impact. It is suggested that the four ports should be encouraged to develop their specializations. However, are the benefits to the shipping industry in following such a policy outweighed by the losses to the local economies because investment in certain ports does not take place?  相似文献   
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