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131.
A three-stage approach, i.e., factor-cluster-multi-group Structural Equation Modeling (SEM), is designed to explore the commonalities and diversities with respect to relationships between socio-demographic characteristics and time-use patterns across different segments. Factor-cluster analysis is conducted to extract meaningful factors from attitudinal statements, and then group the sample population into three segments, each with a unique combination of mode preferences for public transit, private car, and motorcycle. By virtue of multi-group SEM, the relationships between socio-demographics and time allocated to activities and travel are found to be significantly different across segments. This study highlights the importance of latent psychological factors in segmentation. For policy implication, specific population with unique psychological features must be targeted in order to efficiently and effectively design and implement transport measures. 相似文献
132.
This paper studies the supply variables that influence the destination and route choices of users of a bicycle sharing system in the Chilean city of Santiago. A combined trip demand logit model is developed whose explanatory variables represent attributes relating to the topology of the possible routes and other characteristics such as the presence of bikeways, bus service and controlled intersections. The data for the explanatory variables and system users were collected through field surveys of the routes and interviews conducted at the system stations. The results of the model show that proximity to stops on the Santiago Metro and the existence of bikeways are the main factors influencing destination and route choices. Also indicated by the model estimates are gender differences, a preference for tree-lined routes and an avoidance of routes with bus services. Finally, the outcomes reveal considerable potential for the integration of bicycle sharing systems with Metro transit. 相似文献
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将矢量传感器组合指向性vs的零点对准已知的相干干扰方向,获得"干净"的目标信号,然后结合自适应算法抵消矢量传感器原始数据中各通道的相干干扰,达到抗相干干扰的目的.文中阐述了方法的原理,进行了多种情况下的仿真,并给出实验结果.仿真和实验结果表明该方法能有效抑制方位已知的相干干扰. 相似文献
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Carlos Alberto Riveros Tomoaki Utsunomiya Katsuya Maeda Kazuaki Itoh 《Journal of Marine Science and Technology》2010,15(1):44-53
Several research efforts have been directed toward the development of models for response prediction of flexible risers. The
main difficulties arise from the fact that the dynamic response of flexible risers involves highly nonlinear behavior and
a self-regulated process. This article presents a quasi-steady approach for response prediction of oscillating flexible risers.
Amplitude-dependent lift coefficients are considered, as is an increased mean drag coefficient model during synchronization
events. Experimental validation of the proposed model was carried out using a 20-m riser model excited by forced harmonic
vibration at its top end. Large variations in the hydrodynamic force coefficients, a low mass ratio value, and synchronization
events are the main features of the model presented in this article. Experimental validation was provided for the asymmetric,
transverse, diagonal, and third vortex regimes. 相似文献
137.
This article presents a summary of the analyses and set of recommendations given by a committee of transit specialists gathered by the Minister of Transport of Chile aiming at improving Transantiago, the new transit system recently inaugurated for Santiago. This summary focuses on those recommendations directed towards improving the efficiency, service quality and sustainability of mass public transportation systems in major cities in the developing world and that could be implemented in a short term (within two years). Three broad dimensions of public transit are considered: competition and regulation; investment, financing, fares and subsidies; and the operation and use of infrastructure, design, inspection and control. Although the study grew out of the needs and characteristics of a city such as Santiago (Chile), and of the virtues and deficiencies of Transantiago, much of the analyses and recommendations could be adopted and implemented in the major cities of developed countries in Europe, North America and Asia. 相似文献
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