中国航空货运顾客价值动因的实证研究

通过考察中国航空货运,建立航空顾客价值的决定因素与动态性理论模型,运用结构方程方法对其检验,结果表明:时间因素和便捷性因素是影响货运顾客价值的核心要素,价格因素已退之其次,而且来自竞争者、服务商、顾客、宏观环境的变化都对顾客价值动态性有显著影响。     

论农业结构调整的生态基础

我国目前进行的新一轮农业结构调整，无论从形式、内容，还是手段、目标上都与以往有很大 的不同。从农业生产的本质特征出发，农业结构的调整应该在农业系统运作的规律范围内进行。在目前我国农业生态系统已经遭受破坏的状况下，农业结构调整的一项重大任务就是按照自然规律，重新整合农业生态系统，从而恢复系统内部被人为破坏的种种秩序。     

基于网络规划的道路系统设计

针对物流系统设计，基于网络规划法提出了一种在物流中心已经确定的条件下，进行道路系统的新的设计方法。通过合理但设把道路系统的设计转变为网络规划中求解最短路径的问题．通过统计每个路段的最短路径通过率．得出路段的运量负担情况，从而为道路的功能和等级设计提供依据。在此基础上．以宁波化工区的物流系统为例，建立了宁波化工区道路系统的网络模型，对宁波化工区的道路系统进行了功能设计。结果表明，该方法在区域物流系统设计中有良好的应用前景．     

Multiple aspect testing for case-control designs

When testing for the equality of two distributions in a case-control design with treatment effects presumed to act possibly on more than one aspect, different tests may be properly considered for testing for different features of a null hypothesis, leading to the multiple aspect testing issue. Two different aspects are therefore of interest: the location-aspect, based on the comparison of location indexes, and the distributional-aspect, based on the comparison of the empirical distribution functions. A simulation study shows that the combined testing procedure exhibits a good robust overall performance, and an application in biomedical research is also presented.     

Important Intermediate Transactions and Multi-sectoral Modelling

For the maintenance and development of a disaggregated econometric model, the present paper deals with some aspects related to the identification of important intermediate transactions. First, some methodological aspects related to earlier works are discussed. By comparing the properties of different selection methods based on the recent West German input–output table, the calculations confirm the common finding that the necessary level of endogenization can be bounded meaningfully by an a priori investiga tion of the intersectoral transactions. This is also valid if the selection method considers restrictions that deal with the consistence of input–output tables and if some broader error criteria are applied. The main result of the empirical applications seems to be that some attention should be paid to temporal changes of important coefficients.     

Linking performance drivers in production planning and inventory control to process choice

This study investigates how process choice relates to production planning and inventory control decisions. We empirically examine the validity of deductively derived patterns about these types of decisions. More importantly, we look for normative insights by exploring how production planning and inventory control decisions affect operations performance. Our findings show that production line and continuous flow plants use more of a level production strategy, and carry less raw material and work-in-process inventory. The performance drivers for these plants, through which the operations function excels, are effective utilization of equipment, reduced finished goods inventory, and reduced setup down time. To gain forward demand visibility and batching economies, job and batch shops rely much more on backlogs in their planning process. These plants use more of a production chase strategy and position inventory lower in the bills of materials. Four performance drivers for top-performing job and batch shops are to find ways that better anticipate customers' orders, have a more responsive chase strategy, carry less raw material or purchased inventory, and shorten production planning horizon, partly through less reliance on backlogs. It is intriguing that top-performing plants not only do the expected things, given their choice of process, but also excel in selected dimensions—some of which fit the profile normally associated with a different process choice. To monitor and continuously improve operations, evaluation ‘scorecards’ should pay particular attention to performance drivers, which change depending on the plant's process choice.     

Robustness to the unavailability of data in block designs

We present general results for finding or boundingt _maxB , the maximum number of arbitrary whole blocks of observations which can be removed from a block design, and still leave all of the elementary treatment contrasts estimable. The block sizes may be larger than the number of treatments. The results are applied to BBDs, reinforced BIBDs and BBDs, BTIBDs, and a series of variance balanced incomplete block designs with two block sizes. Also given for most of these designs, are results fort _max, the maximum number of arbitrary, scattered observations that can become unavailable, and still leave all of the elementary treatment contrasts estimable.The work was undertaken while Dr. Whittinghill was visiting Ohio State University, and supported by a grant from the Natural Sciences Division, Colby College, Waterville, Maine.     

企业信息化项目管理对项目成功的影响研究

在企业信息化项目中,项目管理是企业深化改革和提高信息化效益的重要途径。但是项目管理究竟在项目建设中发挥了多大作用,对项目成功起到了怎样的影响,这一直以来都是一个模糊的概念。文章通过问卷调查和结构方程模型具体衡量项目管理对项目成功的影响程度。     

生态园林城市规划理论研究

分析了生态园林城市的概念及提出背景;对园林城市、生态园林城市、生态城市建设理论模式进行了辨析;探讨了生态园林城市规划理念,即整体协调发展理念、综合要素统筹理念、有限目标理念、城市开敞空间管制理念、科学指标体系理念;指出生态园林城市实现生态化的主导途径为城市结构生态化和城市功能生态化;提倡在继承、发展和保护的基础上规划生态园林城市的主体--生态园林绿地系统.     

基于供应链的物流网络设计研究

比较分析了基于供应链的物流网络的设计特点,并提出了其设计原则与设计步骤.