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International shipping is a significant contributor to global greenhouse gas (GHG) emissions, and is under mounting pressure to contribute to overall GHG emission reductions. There is an ongoing debate regarding how much the sector could be expected to reduce emissions and how the reduction could be achieved. This paper details a methodology for assessing the cost-effectiveness of technical and operational measures for reducing CO2 emissions from shipping, through the development of an evaluation parameter called the Cost of Averting a Tonne of CO2-eq Heating, CATCH, and decision criterion, against which the evaluation parameter should be evaluated. The methodology is in line with the Intergovernmental Panel on Climate Change (IPCC) and with regulatory work on safety and environmental protection issues at the International Maritime Organization (IMO).

The results of this study suggest that CATCH <50 $/tonne of CO2-eq should be used as a decision criterion for investment in emission reduction measures for shipping. In total, 13 specific measures for reducing CO2 emissions have been analysed for two selected case ships to illustrate the methodology. Results from this work shows that several measures are cost effective according to the proposed criterion. The results suggest that cost effective reductions for the fleet may well be in the order of 30% for technical measures, and above 50% when including speed reductions. The results of this study show that the cost effectiveness approach for the regulation of shipping emissions is viable and should be pursued in the ongoing regulatory process.  相似文献   
2.
Wave-induced load effects in an idealized deep water jacket are considered. The structure is selected more to examine the worst effects of wave-induced uncertainties than to represent a realistic North Sea installation. The largest natural period is about 5 9 s and the structural response is significantly affected by dynamics. The structural system is linearized and response extremes are predicted by means of a stochastic, dynamic long term response analysis. A realistic modelling of ocean waves for long term response calculations is outlined. Various possibilities concerning the choice of wave spectrum are included and the corresponding effects on the predicted extremes are demonstrated. A sensitivity study is carried out both for the quasi-static response and for the resulting dynamic response. Finally, the effects of accounting for wave directionality are indicated. This includes both the introduction of a varying main wave direction and the modelling of the shortcrestedness for a given sea state.  相似文献   
3.
This paper evaluates various computational methods used to compute propeller performance, hydrodynamic side force and bending moment applied to an azimuth propulsor propeller shaft in oblique inflow. The two non-viscous models used are the BEM method and the blade element momentum theory (BEMT). RANS calculations are used to compute the loads on the propeller and the nominal wake velocity from the thruster body to be used in the BEMT model. The effect of the ship hull is also considered in the calculation by implementing the measured nominal wake of a ship hull at different propeller azimuthal positions. All the models are compared and validated against the experimental results, and the discussions are presented.  相似文献   
4.
The purpose of this paper is to investigate the dynamics of forward freight rate dynamics. We specify our model in a Heath–Jarrow–Morton framework. This model was originally developed for interest rate markets and, in subsequent work, the model has been applied to various commodity markets. We analyse ten years of weekly time charter (TC) rates for a Panamax 65,000?dwt bulk carrier. Our data set consists of 6-, 12- and 36-month TC rates. We use this data to construct, each day, a forward rate function using a smoothing algorithm. We use the smooth data to investigate the factors governing the dynamics of the forward freight rate curve. We find a strange volatility structure in the data. Out results show that the volatility of the forward curve is bumped, with volatility reaching a peak for freight rates with roughly one year to maturity. Also, correlations between different parts of the term structure are in general low and even negative.  相似文献   
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The purpose of this paper is to investigate the dynamics of forward freight rate dynamics. We specify our model in a Heath-Jarrow-Morton framework. This model was originally developed for interest rate markets and, in subsequent work, the model has been applied to various commodity markets. We analyse ten years of weekly time charter (TC) rates for a Panamax 65,000 dwt bulk carrier. Our data set consists of 6-, 12- and 36-month TC rates. We use this data to construct, each day, a forward rate function using a smoothing algorithm. We use the smooth data to investigate the factors governing the dynamics of the forward freight rate curve. We find a strange volatility structure in the data. Out results show that the volatility of the forward curve is bumped, with volatility reaching a peak for freight rates with roughly one year to maturity. Also, correlations between different parts of the term structure are in general low and even negative.  相似文献   
7.
The record of public involvement in the transportation planning process in the United States has been uneven and, at times, disappointing. It is therefore a matter of some satisfaction that the Intermodal Surface Transportation Efficiency Act of 1991 (ISTEA), recognizes that public involvement and input is essential in transportation plan-making. However, little guidance is available to planners as to how participatory democracy could possibly be enhanced and improved in the existing transportation planning process. As matters stand today, the predominant use of technical rationality in the planning process, to the exclusion of communicative action, has probably been the biggest problem. This paper introduces the concepts of communicative action to buttress and complement technical rationality, currently used in the transportation planning process. A real-life case-study is presented to demonstrate how communicative action was successfully used in a problem-ridden planning situation. Validity claims as suggested by Habermas in his Theory of Communicative Action are used in this case-study. It is concluded that academic institutions as well as planning agencies will have to make a concerted effort to educate and train planners not only to be involved with the engineering of our infrastructure, but also to be equally concerned with coping with the social, economic and political dimensions of planning.  相似文献   
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