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A survey of U.S. and European responses to the energy crises engendered by the Arab boycott of October 1973–April 1974 is presented. U.S. Government policy actions with respect to allocation, rationing, price, and conservation measures are reviewed and contrasted with those of affected European governments. The results of those policies and their effects on transportation energy supply and demand behavior with respect to both commodity and passenger movement are described.Based on short- and long-term impact assessments of the policies considered, the authors identify significant research requirements.The authors were heavily engaged in U.S. responses to the energy emergency, and were asked to undertake study missions to those European nations significantly affected by the crisis to seek out avenues for mutual aid, and joint research, in resolving common energy problems. This paper is one product of those study missions.  相似文献   
2.
This article draws lessons about recent innovations in decision support for coping with challenges in integrated infrastructure planning strategies. After setting up a conceptual framework for the scope of analysis and the use of information in infrastructure planning, the empirical section explores the introduction of early-stage sustainability assessment tools. Data collection draws on experiences gained in the Netherlands with a new tool: ‘Sustainability Check’. We conclude that such instruments have a number of capacities that address the challenges of area-oriented planning: (a) bringing together information about the comprehensive value of alternatives, (b) facilitating the generation of alternatives, (c) addressing institutional fragmentation by learning about referential frames, and (d) adding contextual perspectives to the ‘hard’ outcomes of conventional tools. We also conclude that tools such as Sustainability Check should not be seen as a replacement for conventional decision support tools, but rather as complementary to them.  相似文献   
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This paper evaluates the influence of forecast horizon and observation fit on the robustness and performance of a specific freight rate forecast model used in the liner shipping industry. In the first stage of the research, a forecast model used to predict container freight rate development is presented by exploring the relationship between individual company’s rates and aggregated market rates, and thus assists in dealing with uncertainty and market volatility for a given business situation. In the second stage, a design of experiment approach is applied to highlight the influence of the forecast horizon and observation fit and their interactions on the forecast model’s performance. The results underline the complicated nature of creating a suitable forecast model by balancing business needs, a desire to fit a good model and achieve high accuracy. There is strong empirical evidence from this study; that a robust model is preferable, that overfitting is a true danger, and that a balance must be achieved between forecast horizon and the number of observations used to fit the model. In addition, methodological guidance has also been provided on how to test, design, and choose the superior model for business needs.  相似文献   
4.
Transportation - Simulation studies suggest that pooled on-demand services (also referred to as Demand Responsive Transport, ridesharing, shared ride-hailing or shared ridesourcing services) have...  相似文献   
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Abstract

Section 312 of the Clean Waters Act was implemented in 1980 and requires all vessels including recreational boats already equipped with Marine Heads (toilets) to install one of three types of USCG approved Marine Sanitation Devices. These regulations govern all lakes and coastal waters extending to the end of the U.S. territorial sea and is intended to prevent untreated effluent from reaching the marine environment. As provisions of the Clean Water Act are exempt from provisions of the National Environmental Policy Act, no Environmental Impact Statement was written concerning the impacts to the marine environment and the cost to the boating public. The study based on a small survey conducted on Narragansett Bay during the summer of 1980 develops several empirical models to estimate the total costs of MSD conversions. These estimates assume that all recreational boats longer than 21 feet were to comply with Section 312 regulations. Biological Oxygen Demand generated waste by both the resident and visiting fleets have also been estimated and costs per lbs. of BOD equivalent made. Based on these estimates the quantity of waste prevented from entering the receiving waters equals that of a community with less than 700 people. The capital investments of on‐board treatment approximates 30 ¢/gallon, nearly 1000 times the cost of treating municipal waste.  相似文献   
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Smartphone technology enables dynamic ride-sharing systems that bring together people with similar itineraries and time schedules to share rides on short-notice. This paper considers the problem of matching drivers and riders in this dynamic setting. We develop optimization-based approaches that aim at minimizing the total system-wide vehicle miles incurred by system users, and their individual travel costs. To assess the merits of our methods we present a simulation study based on 2008 travel demand data from metropolitan Atlanta. The simulation results indicate that the use of sophisticated optimization methods instead of simple greedy matching rules substantially improve the performance of ride-sharing systems. Furthermore, even with relatively low participation rates, it appears that sustainable populations of dynamic ride-sharing participants may be possible even in relatively sprawling urban areas with many employment centers.  相似文献   
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