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921.
Industrialized countries have extensive experience with various transportation energy conservation measures and have been making steady progress in improving the efficiency of their transport sector. Less Developed Countries (LDCs) have also been making progress, but their experience in many aspects of transportation energy conservation is very limited. Development organizations have funded many transportation projects in developing countries, but the vast majority of these projects were designed to improve the transportation infrastructure. Very few transportation energy conservation projects have been implemented and decision-makers face a scarcity of information on effective strategies. This paper gives an overview of transportation projects in LDCs in order to identify those transportation energy conservation measures that offer the greatest potential for LDCs. Two case studies, from Tunisia and Costa Rica, are given to illustrate the issues involved in implementing transportation energy conservation measures in LDCs. Conclusions are drawn to suggest actions for developing countries and for development organizations.Acronyms DECAT
Driver Energy Conservation Awareness Training
- DSE
Direccion Sectorial de Energia (Costa Rica)
- GDP
Gross domestic product
- km
Kilometer
- LDCs
Less Developed Countries
- TOE
Metric tonne of oil equivalent
- USAID
US Agency for International Development 相似文献
922.
D. N. L. Horton D. A. Crolla 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》1986,15(6):351-372
A theoretical analysis is presented to model a hydromechanical, semi-active suspension system, first as a single wheel station and then as fitted to each wheel of an off-road vehicle. Predicted results show that two benefits are obtained by comparison with the equivalent passive system. First, vehicle attitude is controlled for changes in body forces arising from static loads or braking/cornering inputs. Second, a significant improvement in ride comfort is obtained because low suspension stiffnesses can be used. 相似文献
923.
This paper draws from the findings of published empirical studies and observations of the impacts of rapid transit systems on urban development. Analysis is based on comparisons of impact findings by different researchers and for different cities. An initial set of key issues is proposed, against which available information is arrayed and compared. It is concluded that rapid transit can have substantial growth-focusing impacts, but only if other supporting factors are present. 相似文献
924.
INTERFERONγ-INDEPENDENTEFFECTSOFINTERLEUKIN12ADMINISTEREDDURINGACUTEOR ESTABLISHEDINFECTIONDUETOLEISHMANIAMAJORZhengShichun;W... 相似文献
925.
郑时春 《西安交通大学学报(英文版)》1995,(2)
CONSTRUCTINGPOLYCOMPETITORCDNASFORQUANTITATIVEPCRS.L.Reiner,Zheng,Shichun;D.B.Corry,R.M.Locksley(DepartmentofMedicineandMicro... 相似文献
926.
927.
The logit modeling methodology is applied to include transit access mode choices in conjunction with the automobile vs. transit travel choice decision. The practical problems that arise when the choice set expands beyond two alternatives are identified and addressed. In particular, the complexities that must be resolved in order to use ULOGIT or a similar program include the definition of independent choices (the Independence of Irrelevant Alternatives Property (IIA)), a sequential binary or multinomial logit model (MNL) structure, specification and testing of variables, and the potential for transferring the model to new areas for transportation planning purposes. It was found that the available options cannot be reduced to a single modeling strategy. However, the analysis showed certain concepts which can reduce the uncertainties in related applications of the logit model. It was determined that as many independent choices as possible should be hypothesized and tested for inclusion in the model, but the IIA must be carefully considered because it limits the number of choices that can be represented. Although binary calibration techniques are conceptually appealing, the large number of calibrations for studies involving more than three alternatives suggests that the MNL approach is most practical. Application of the MNL model requires that not only must variables be selected that best explain choice, but they must also be placed in the disutility function of the specific mode or modes to which they are most unique. Finally, it was shown that if choice sets and homogeneous market segments are properly defined, the models can be transferred among different urban areas even though the urban areas exhibit different aggregate characteristics. All observations lead to the general conclusion that the logit modeling methodology can now best be advanced with implementation experience. 相似文献
928.
Dynamic Interaction of Vehicles with Tracks and Roads 总被引:1,自引:0,他引:1
L. Frý ba 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》1987,16(3):129-138
The principle problems of the new developing scientific field - dynamics of vehicles, tracks and roads - are defined. Basic theoretical models for the analysis of railway and road vehicles, tracks and roads and principle methods of their solution are shown. The dynamic interactions between vehicles and routes are emphasized and several basic equations are given to show the behaviour of their elements. The effect of some parameters, like speed, track or roads irregularities etc. is explained. The possibilities are described how to simplify the theoretical models to obtain a simple solution. 相似文献
929.
930.
通过介绍微控自动式制动技术和微控直通式制动技术在我国轨道车辆上的应用,对其各自的特点进行 了分析,提出了我国轨道车辆选用微控自动式制动技术和微控直通式制动技术的建议。 相似文献