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911.
Abstract

The Internet service attributes desired by shippers were examined as well as a model that seeks to explain the intention of shippers to use Internet services in liner shipping. Using data collected from a survey of a group of shippers in Taiwan, the relationships among the constructs in the model were tested, namely: perceived usefulness, perceived ease of use, security and use intention. The results suggest that shippers perceive tracing to be the most important service attribute of Internet services, followed by checking for customs clearance, vessel schedules and electronic document services. The findings indicate that perceived ease of use is the major factor affecting the intention of shippers to use Internet services, and that perceived ease of use has a strong positive effect on perceived usefulness. The results also indicate that security has a positive effect on a shipper’s perception of ease of use. However, the influence of security on use intention and perceived usefulness was not supported in this study. The theoretical and practical implications of the findings on the intention of shippers to use Internet services in liner shipping are discussed.  相似文献   
912.
Review of GPS Travel Survey and GPS Data-Processing Methods   总被引:1,自引:0,他引:1  
Abstract

Global positioning system (GPS) devices have been utilised in travel surveys since the late 1990s. Because GPS devices are very accurate at recording time and positional characteristics of travel, they can correct the trip-misreporting issue resulting from self-reports of travel and improve the accuracy of travel data. Although the initial idea of using GPS surveys in transport data collection was just to replace paper-based travel diaries, GPS surveys currently are being applied in a number of transport fields. Several general reviews have been done about GPS surveys in the literature review sections in some papers, but a detailed systematic review from GPS data collection to the whole procedure of GPS data processing has not been undertaken. This paper comprehensively reviews the development of GPS surveys and their applications, and GPS data processing. Different from most reviews in GPS research, this paper provides a detailed and systematic comparison between different methods from trip identification to mode and purpose detection, introduces the methods that researchers and planners are currently using, and discusses the pros and cons of those methods. Based on this review, researchers can choose appropriate methods and endeavour to improve them.  相似文献   
913.
This paper aims to provide a state-of-the-art review of the transport network design problem (NDP) under uncertainty and to present some new developments on a bi-objective-reliable NDP (BORNDP) model that explicitly optimizes the capacity reliability and travel time reliability under demand uncertainty. Both are useful performance measures that can describe the supply-side reliability and demand-side reliability of a road network. A simulation-based multi-objective genetic algorithm solution procedure, which consists of a traffic assignment algorithm, a genetic algorithm, a Pareto filter, and a Monte-Carlo simulation, is developed to solve the proposed BORNDP model. A numerical example based on the capacity enhancement problem is presented to demonstrate the tradeoff between capacity reliability and travel time reliability in the NDP.  相似文献   
914.
Abstract

This paper models trip generation for a cross-section of residential developments around the UK. Consistent with recent literature, the empirical model tests whether trip making patterns for residential developments are independent of car ownership and finds that trip generation is dependent upon car ownership socio-economic factors and site-specific characteristics, in particular land-zone type (e.g. town centre, out of town, etc.). However, public transport services are not found to have a significant relationship with trip generation; consequently, a policy implication of the results is that increasing bus services to residential developments is not associated with a reduction in generated trips.  相似文献   
915.
Abstract

This paper presents a decision support methodology for long-range planning of transport systems that exhibits strategic flexibility and stochastic system parameters. Unlike one-off strategic decisions, flexible decisions should be dynamically reformulated with time. The proposed methodology is based on the construction of a tree structure of multiple interlinked tactical planning problems, each associated with a scenario in the tree, where problems under scenarios at intermediate dates incorporate in their formulation the solution of the corresponding problems associated with past (future) connected scenarios. The resulting tree structure of interconnected planning decisions becomes a strategic-tactical decision support system that allows managers to formulate suitable flexible strategic decisions that mitigate the consequences associated with downside scenarios while taking advantage of the upside opportunities. The methodology is applied to the planning of a fleet deployment through charter contracts where contract prices depend on both market behavior and the duration of the contract itself.  相似文献   
916.
高危害交通事故是指在交通事故统计中造成主要人员伤亡及财产损失的事故,为识别高危害交通事故的主要形态,探寻其致因,提出一种基于灰色理论的分析方法.将道路交通事故危害程度划分为4个灰类,构建4个灰类的白化权函数,通过灰色定权聚类系数确定高危害交通事故的主要形态和致因.以深圳市为例,基于全年交通事故数据,识别出深圳市高危害性交通事故的4类主要形态和6种主要致因.研究表明:车辆碰撞是高危害事故的主要形态,驾驶过程中妨碍安全行车的行为、酒驾以及未保持安全车距等是产生高危害事故的主要原因.针对高危害交通事故的主要形态和致因,提出相应的交通安全管理对策,有利于减少高危害交通事故,提升道路安全水平.  相似文献   
917.
为了响应国家中部崛起战略,分析武汉港口物流与核心腹地经济发展之间的关系.根据2000~2010年武汉市港口物流与经济发展的数据,利用协整理论及其计量学分析软件eviews6.0,对武汉市港口物流与经济发展进行协整分析.通过协整检验发现,港口物流与区域经济发展之间存在长期的均衡关系;Granger因果检验表明,港口物流与经济发展之间存在单向的Granger因果关系,经济发展是港口集装箱吞吐量的格兰杰原因,表明武汉经济快速发展促进了港口集装箱吞吐量的增长,是港口物流发展的重要推动力.  相似文献   
918.
900 t轮胎式提梁机是为高速铁路施工而开发的新机型。其主要功能是在预制梁场内对混凝土箱梁进行起吊、搬运和配合运梁车进行装车;其具有性能稳定、高效、功能集成化高的特点。主要介绍900 t轮胎式提梁机吊杆在吊运过程中的主要受力情况及在不同工况情况下的受力分析,根据最不利的工况进行有限元分析,分析结果跟实际应用中探伤结果进行比较,发现设计的吊杆可以满足1 000次吊装,并且改进延长探伤时间为加工吊杆提供优化的设计方案。  相似文献   
919.
Defect control at nanoscale of MgB2 by doping various nanoparticles including Ti,C,nano-diamond,and HoB4,and their roles played to enhance flux pinning force in MgB2 arc compared and analyzed.These nan...  相似文献   
920.
The purpose of the study was to test the biomechanical differences between a lateral wedge and a valgus knee bracing on the knee joint moment during walking in patients with early stage of medial compartment knee osteoarthritis (OA). We conducted a crossover randomized design to compare gait parameters of 32 patients (with early stage medial compartment knee OA) in three different conditions during walking: with a custom-made lateral wedge of 5° (in standard shoes), with a valgus knee bracing (in standard shoes), and with control condition (in standard shoes). Both two-orthose conditions showed decreased loading patterns (knee adduction moment and knee adduction angular impulse) on the knee joint in dynamic condition (statistic probability P < 0.05). The decreased loading on OA knee in wedge condition was associated with a laterally shifted location of centre of pressure and increased ankle valgus degree and moment at the same foot (P < 0.05). It was not found significant differences in loading of the knee between these two-orthose conditions. These results indicated that, under dynamic condition, patients wearing lateral wedge and valgus knee bracing showed changes of moments on knee joints. Lateral wedge was as effective as valgus knee bracing in the treatment of early stage of knee OA.  相似文献   
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