Defining and understanding trip chaining behaviour

Trip chaining is a phenomenon that we know exists but rarely investigate. This could be attributed to either the difficulty in defining trip chains, extracting such information from travel diary surveys, the difficulty in analysing all the possible trip chain types, or all of the above. Household travel diary surveys provide a wealth of information on the travel patterns of individuals and households. Since such surveys collect all information related to travel undertaken, in theory it should be possible to extract trip-chaining characteristics of travel from them. Due to the difficulty in establishing and analysing all of the possible trip chain types, the majority of research on trip chaining has appeared to focus on work travel only. However, work related travel in many cities does not represent the majority of activities undertaken and, for some age groups, does not represent any travel at all. This paper begins by reviewing existing research in the field of trip chaining. In particular, investigations into the definitions of trip chaining, the defined typologies of trip chains and the research questions that have been addressed are explored. This review of previous research into trip chaining facilitates the following tasks: the identification of the most useful questions to be addressed by this research; defining trip chaining and associated typologies and defining data structures to extract trip chaining information from the household travel surveys conducted in metropolitan Adelaide, South Australia. The definition and typology developed in our research was then used to extract trip-chaining information from the household travel diary survey (MAHTS99) conducted in Adelaide in 1999. The extracted trip chaining information was then used to investigate trip-chaining behaviour by households. The paper reports the results of this analysis and concludes with a summary of the findings and recommendations for further investigations.     

Container terminal employees’ perceptions of the effects of sustainable supply chain management on sustainability performance

ABSTRACT

Sustainability has become an important issue in container terminal operations. However, relatively little research has been conducted to assess its association with sustainable supply chain management (SSCM). In this study, SSCM consists of internal sustainability practices and external sustainability collaboration. We empirically examined the effects of internal sustainability practices and external sustainability collaboration on sustainability performance in container terminal operations at the Port of Kaohsiung in Taiwan. We developed a model adopting the SSCM construct, which consisted of two dimensions: internal sustainability practices and external sustainability collaboration. Several research hypotheses were formulated from the theory and the hypotheses were tested using survey data collected from 141 employees who worked with container terminals. We found that internal sustainability practices and external sustainability collaboration positively affected sustainability performance, whereas external sustainability collaboration had a positive influence on internal sustainability practices. There is a discussion of the implications of these findings for developing sustainability and improving sustainability performance in container terminals and ports.     

关于国内建立汽车维修连锁店的研究

本文针对目前国内汽车维修行业的状况,提出了建立汽车维修连锁店的方案。通过设计一个维修店面来说明维修连锁店一体化服务的优点。介绍了建立维修连锁店所需要的条件,即维修店选址的重要性。总结了汽车维修连锁店组织管理的原则,并针对维修店的经营模式提出了解决的方法。     

Education influence in traffic safety: A case study in Vietnam

It is well known that traffic accidents are of high importance to the public health spectrum around the world. Moreover, in developing countries such as Vietnam, the mortality rate from road traffic accidents is rather high in comparison with other Southeast Asian countries. Not only do the majority of the people killed and seriously injured significantly affect the quality of life of the citizens, but traffic accidents also negatively impact a nation's economic and social development. Statistics show that far more people are injured or die in traffic accidents than are afflicted by any of the most serious diseases. The very high occurrence of traffic accidents in Vietnam has become one of the country's major social issues. The importance of human factors in transport policy discussion is growing. There is a realization that policy options that appear beneficial in principle have to be checked for their feasibility of implementation. Understanding and describing driver behavior become a challenge when one tries to identify driver errors in determining accident/conflict causal factors and countermeasures.In recent years, having understood the serious effects of traffic accidents on society at large, scientific researchers, traffic engineers and policy makers in Vietnam have developed many projects and conducted research in the field of traffic safety. The human factor is also considered to be the central element in the whole system. The final goal is to organize a traffic environment that is convenient and safe for road users.This article explains the application of the risk analysis approach in evaluating influences of education and enforcement in traffic safety.     

基于双层规划的多次运输供应采购模型

同时考虑供应商和订货商的利益,以供应商为主方,订货商为从方,建立了基于双层规划的供应采购模型.供应商依靠产品定价影响下层的决策来获得最大利润,而订货商决定订货批量以及每个订货批量要求的运输次数来使自身成本最低,进而影响供应商的决策.根据模型特点设计了基于遗传算法的求解方法,并用数值算例验证了模型和算法的有效性.     

基于供应链思想的第四代港口战略决策分析

第四代港口的概念本质上供应链集成思想一种具体运用,其战略决策要把参与港口供应链中的所有成员组织视为一个视整体.在制定第四代港口战略决策时先要明确其角色定位,建立面向客户需求的港口供应链网络,组建适宜的机制和结构来实现对供应链的协同管理.探讨了库存、运输、设施、信息和配套服务5个战略决策要素的不同设计对港口供应链顾客需要的影响.     

内脂素基因多态性与2型糖尿病的关系

目的探讨内脂素(visfatin)rs11977021、rs12537455、rs2110385位点单核苷酸多态性与2型糖尿病易感性的关系。方法收集陕西西安地区汉族人群192例受试对象,其中106例单纯2型糖尿病(T2DM)患者和86例健康对照者,采用标准化的聚合酶链反应-限制性片段长度多态性(PCR-RLFP)方法,分别检测内脂素(visfatin)rs11977021/DdeⅠ、rs12537455/AluⅠ和rs2110385/AluⅠ基因型并进行比较。结果 rs2110385位点的T等位基因频率和GT基因型频率在T2DM组均高于健康对照组(分别为28.3、14.0和14.2、7.0,P均<0.05);两组的rs11977021位点和rs12537455位点C、T等位基因及基因型频率分布均无统计学差异(P>0.05);单倍型分析显示T-C-T和T-T-T单倍型在T2DM组均显著高于健康对照组(分别为0.066、0.026和0.029、0.012,P均<0.05)。结论 Visfatin基因rs2110385位点在陕西西安汉族地区人群中存在遗传变异,其rs2110385多态性位点的T等位基因可能与T2DM的发病风险有一定的关系。     

共存递质囊泡循环动力学研究细胞模型的建立

目的直接证明PC12细胞能够合成和分泌组胺(histamine,HA),为将其应用于交感神经共存递质囊泡循环动力学研究提供实验依据。方法常规培养PC12细胞,用嵌套RT-PCR(nRT-PCR)和Western blot技术检测其合成HA的关键酶组氨酸脱羧酶(histidine decarboxylase,HDC)的mRNA和蛋白表达,利用免疫荧光技术观测HA、HDC以及HA囊泡在细胞中的定位。结果从基因和蛋白水平均证实了该细胞中表达HDC,并利用形态学方法在细胞中检测到HA、HDC以及HA囊泡的存在。结论 PC12细胞确实含有HA,结合分化型PC12细胞与交感神经元相似的特征,可将其作为交感神经共存递质囊泡循环动力学研究的理想细胞模型。     

基于供应链的铁路工程项目质量管理体系研究——以京沪高铁济南黄河大桥为例

主要探讨基于供应链环境下的铁路工程项目质量管理体系.以京沪高铁济南黄河大桥工程项目为例,建立了基于供应链的质量策划、质量保证、质量控制和质量评价体系.     

Numerical investigation of mooring line damping and the drag coefficients of studless chain links

The chain/wire rope/chain combination is a commonchoice for mooring offshore floating platforms. However, data ofthe drag coefficients of chain links are rather limited, resulting inuncertainties with the calculations of the drag force, and hence thedamping of the mooring system. In this paper, the importance of theselection of the drag coefficient is first investigated. Thecomputational fluid dynamics （CFD） method is then used todetermine the drag coefficients of a studless chain under steadyflows. Numerical model validation is first completed by simulatinga smooth circular cylinder under steady flows. In particular, theperformance of different turbulence models is assessed through thecomparisons between the calculations and the experimental results.The large eddy simulation （LES） model is finally selected for thesimulation of steady flows past a chain. The effects of the Reynoldsnumber on the drag coefficient of a stud-less chain is also studied.The results show that the calculated drag coefficients of a stud-lesschain are fairly consistent with the available experimental data.