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排序方式: 共有925条查询结果,搜索用时 31 毫秒
821.
Chia-Hsun Chang 《Maritime Policy and Management》2013,40(6):720-736
ABSTRACTThis study uses Kaohsiung Port as a case study to evaluate the relationships between port security quality, port service quality, customer satisfaction, and customer loyalty. For this purpose, a survey was conducted with shipping companies and freight forwarders in Taiwan. The results indicate that port security quality has a direct and positive impact on both port service quality and customer satisfaction; port service quality has a direct and positive impact on both customer satisfaction and customer loyalty; and customer satisfaction has a direct and positive impact on customer loyalty. However, the impact from port service quality is more significant than that of port security quality. Accordingly, this study suggests that Kaohsiung Port should concentrate on improving its service quality in order to enhance customer satisfaction and customer loyalty. 相似文献
822.
介绍了废气涡轮增压器的基本结构及功能,重点论述了涡轮增压器失效的主要原因和工作原理,涡轮增压器的润滑、冷却,以及正确使用与保养涡轮增压器。 相似文献
823.
X. Y. Fan L. Liu S. Q. Chang J. T. Xu J. G. Dai 《International Journal of Automotive Technology》2016,17(3):361-367
Electromagnetic valve train (EMVT) in camless engine offers large potential for both part load fuel economy and high load engine torque. However, it is more difficult to be applied on exhaust system than intake system. Because the gas pressure brings high demands for driving force, especially at high engine speed and full load. Based on the working characters of actuator, a method by increasing the transient currents in windings during valve’s opening motion is suggested to overcome the gas pressure. But this will cause more energy losses and heat. In order to make the EMVT used on exhaust system better, quantitative analysis is carried out against the additional power consumption caused by gas pressure under different conditions. Furthermore, an approach is introduced to define the optimal exhaust valve opening motion at full load conditions. It aims at making a better compromise between the engine power output and exhaust valves’ power consumption, thus both the efficiency of EMVT and engine performance are enhanced. 相似文献
824.
介绍了客运专线接触网支柱参数的测量方法,如何在CPⅢ精测网的基础上对接触网支柱的坐标进行计算及常见的计算方法,如何在测量施工时对测量数据的精度控制,并提出了针对接触网支柱参数的边线测量方法。 相似文献
825.
程畅 《城市轨道交通研究》2012,15(10)
分析了轨道交通监控系统集中式结构和分布式结构的软件模型和硬件配置,从可靠性和成本、实用性和可扩展性、可维护性和单一的应用等方面,对两种结构进行比较.结合轨道交通实际运营需求,提出了不同运营管理模式下的系统构成方案.同时,根据“单一的应用”的概念,对系统构成方案进行了优化,在保证系统可靠性的前提下,提高系统可维护性,达到降本增效的目的. 相似文献
826.
827.
828.
高强化柴油机活塞异型销孔结构设计与试验研究 总被引:5,自引:0,他引:5
针对高强化柴油机活塞,研究了网格数量和活塞销孔棱缘耦合应力的收敛性关系,进行了精确的活塞耦合应力计算;研究了异型销孔结构对活塞应力分布的影响规律;根据耦合应力计算结果,选定异型销孔位置和形状,设计双侧圆锥形异型销孔并进行耦合应力计算,与圆形销孔结构活塞对比可知,异型销孔结构可以大幅度降低销孔棱缘的应力集中,活塞的承载能力有所提高。利用活塞销孔疲劳试验机进行异型销孔活塞的疲劳试验,试验完成1.0×107个循环,活塞销孔表面接触良好,说明双侧圆锥形异型销孔的结构设计满足发动机可靠性要求。 相似文献
829.
B. Suh A. Frank Y. J. Chung E. Y. Lee Y. H. Chang S. B. Han 《International Journal of Automotive Technology》2011,12(1):131-139
This research concerns the design of a powertrain system for a plug-in parallel diesel hybrid electric bus equipped with a
continuously variable transmission (CVT) and presents a new design paradigm for the plug-in hybrid electric bus (HEB). The
criteria and method for selecting and sizing powertrain components equipped in the plug-in HEB are presented. The plug-in
HEB is designed to overcome the vulnerable limitations of driving range and performance of a purely electric vehicle (EV),
and it is also designed to improve the fuel economy and exhaust emissions of conventional buses and conventional HEBs. Optimization
of the control strategy for the complicated and interconnected propulsion system in the plug-in parallel HEB is one of the
most significant factors for achieving higher fuel economy and lower exhaust emissions in the hybrid electric vehicle (HEV).
In this research, the proposed control strategy was simulated to prove its validity using the ADVISOR (advanced vehicle simulator)
analysis simulation tool. 相似文献
830.