Vendor Selection with Bundling*

Product bundling has become increasingly prevalent not only in consumer goods but also in the industrial sector. We study a purchasing problem in which a buyer must obtain necessary numbers of various stock items from a variety of vendors who charge different prices, have limited capacities and different levels of quality, and offer bundled products at discounted prices. We examine relationships among different bundling scenarios and show that the most general scenario is one in which free items are given to the buyer when sufficient quantities are purchased. We develop a mixed integer linear program that finds the purchasing strategy for the buyer that minimizes the total purchase cost. We present computational results which indicate that the problem is very tractable to solve optimally on a personal computer with standard optimization software. Finally, three extensions of the model are discussed.     

A Path Analytic Model of a Theory of Quality Management Underlying the Deming Management Method: Preliminary Empirical Findings*

Despite the impact that Deming and his 14 Points have had on the practice of quality management, empirical support for the effectiveness of the Deming Management Method has not advanced beyond the presentation of anecdotal, case-study evidence. In part, this is because theory to guide the conduct of empirical research has not been available. Only recently has such a theory of quality management to describe and explain the effectiveness of the Deming Management Method been articulated in the literature. This paper continues the journey of theory development; it reports the results of an exploratory empirical analysis of an articulated theory of quality management underlying the Deming Management Method. The constructs in the proposed theory are operationalized using measurement statements developed by the World-Class Manufacturing research project team at the University of Minnesota and Iowa State University. Path analysis is applied to the World-Class Manufacturing project data to explore the empirical strength of relationships advanced in the theory. The path analytic results provide support for several of the proposed relationships in the theory, and more importantly, suggest a number of new relationships which have not heretofore been proposed.     

他者话语的反思：欧美学界关于中国海外藏人研究评析

“西藏问题”,尤其是中国海外藏人问题,是我国党和政府始终关切的重要问题。自1959年西藏叛乱以后,中国海外藏人问题在一些西方国家备受关注,也成为欧美学者们竞相展开调查研究的重要领域,关于这一主题的研究涉及了国际关系、人口迁移、国际援助、难民政策、身份政治、文化传播等诸多领域。本文将在对大量欧美学者的相关专著与论文进行整体把握的基础上,厘清欧美学界海外藏人研究的基本特点,对欧美学界的相关研究状况进行分析,并重点分析了欧美学者对中国海外藏人社区的实地研究,指出许多研究过分服务于政治目的,或研究中情绪色彩过重,或关注点过于集中于中国海外藏人的处境状况。因此,国内的相关研究应发挥本土优势,关注中国海外藏人生活境遇,将海外藏人研究与国内藏族研究相结合,构建起更加完整的藏族研究体系。     

基于时频分析的裂纹转子碰摩故障特征研究

为研究转子系统耦合故障特性,采用有限元方法建立了含有横向裂纹、转静碰摩的非线性转子动力学模型。首先研究了不同转速下裂纹、碰摩单一故障下转子系统的振动响应,其次研究了两种故障耦合情况下系统的振动响应特征。采用波形图、FFT谱图、瞬时频率和Hilbert-Huang时频谱(HHS)相结合的方法对故障转子振动信号进行了分析。分析结果表明:运用多种时频分析相结合的方法可以较为全面地了解转子的故障特征,裂纹转子在1/5、1/3临界转速时会发生较为明显的5X、3X谐波,且裂纹的产生会导致响应幅值增大,从而引起更为严重的碰摩。      

Fifty Years After the Social Indicators Movement: Has the Promise Been Fulfilled?

In spite of its currency both in academic research and political rhetoric, there are numerous attempts to define and conceptualize the social cohesion concept but there has been paid little attention to provide a rigorous and empirically tested definition. There are even fewer studies that address social cohesion in a framework of cross-cultural validation of the indicators testing the equivalence of the factorial structure across countries. Finally, as far as we know there is no study that attempt to provide an empirically tested multilevel definition of social cohesion specifying a Multilevel Structural Equation Model. This study aims to cover this gap. First, we provide a theoretical construct of social cohesion taking into account not only its multidimensionality but also its multilevel structure. In the second step, to test the validity of this theoretical construct, we perform a multilevel confirmatory factor analysis in order to verify if the conceptual structure suggested in first step holds. In addition, we test the cross-level structural equivalence and the measurement invariance of the model in order to verify if the same multilevel model of social cohesion holds across the 29 countries analysed. In the final step, we specify a second-order multilevel CFA model in order to identify the existence of a general factor that can be called “social cohesion” operating in society that accounts for the surface phenomena that we observe.     

Destroyed by Slavery? Slavery and African American Family Formation Following Emancipation

This study introduces a new sample that links people and families across 1860, 1880, and 1900 census data to explore the intergenerational impact of slavery on black families in the United States. Slaveholding—the number of slaves owned by a single farmer or planter—is used as a proxy for experiences during slavery. Slave family structures varied systematically with slaveholding sizes. Enslaved children on smaller holdings were more likely to be members of single-parent or divided families. On larger holdings, however, children tended to reside in nuclear families. In 1880, a child whose mother had been on a farm with five slaves was 49 % more likely to live in a single-parent household than a child whose mother had been on a farm with 15 slaves. By 1900, slaveholding no longer had an impact. However, children whose parents lived in single-parent households were themselves more likely to live in single-parent households and to have been born outside marriage.     

Impact of support networks for breastfeeding: A multicentre study

Background

The rates of breastfeeding worldwide are slowly improving since 1996. Europe is still trailing behind the global breastfeeding incidence and prevalence rates. Thus, breastfeeding promotion, protection, prolongation and support have become an important challenge as breastfeeding sharply decreases in the first six months of life.

互联网医疗服务法律监管研究

随着互联网技术的进步以及医疗改革的深入,互联网医疗服务成为新生业态.然而,我国互联网医疗服务法律监管体系还不够完善,缺乏统一规范的监管体系,多头监管、个人隐私隐患大、纠纷处理解决机制不健全等现实困境尚未解决,不利于互联网医疗服务行业的发展和人民群众身心健康.为解决上述问题,通过梳理发达国家的成功经验,如美国的移动医疗应用程序监管和个人隐私保护、欧盟的互联医疗数据管理、英国的行业协会监管等,结合我国现有国情,建议从完善立法体系、建设隐私保护机制、构建行业监管、明晰医疗服务主体责任等方面健全互联网医疗法律监管制度,以期推动互联网医疗服务行业发展,保障医患双方的合法权益.     

大数据战略视野下我国信息网络安全立法分析

大数据战略视野下,很多国家纷纷制定、完善和执行着自己的信息网络安全法律,并已形成世界潮流.从国内外的大数据战略与信息网络安全立法分析来看,我国既有成绩,也有不足.对于我国信息网络安全的法律保障,目前需要完善的主要内容有:进一步明确国家信息网络安全立法的目的与宗旨;基本法层面,尽快构建完备的信息网络安全法律保障有机体系,重点包括政府信息公开法与个人信息保护法等;实施层面,加强与完善具体领域的单行法与配套法建设,增强法律规定的可操作性;完善法律框架之外的协作保障体系.