Perceived Project Value,Opportunistic Behavior,Interorganizational Cooperation,and Contractor Performance

Predictors of contractor performance have attracted the attention of researchers in the developed world. However, research from sub-Saharan Africa to corroborate these findings has remained sparse. What exists is speculative and at best anecdotal. Using data from construction firms in Uganda, this study finds that commitment to the project, perceived value of the project, interorganizational cooperation, and opportunistic behavior are significant predictors of contractor performance. This has both policy and managerial implications, which we present in this paper.     

离子色谱-电感耦合等离子体质谱法检测玩具中六价铬

建立了用离子色谱-电感耦合等离子体质谱法检测玩具材料迁移液中六价铬的新方法。采用阴离子交换色谱柱、中性NH4NO3淋洗液,结合梯度洗脱和碰撞反应池技术。实验表明,本方法可以很好地分离溶液中的三价铬和六价铬。当进样量为100μL时,对溶液中六价铬的检出限达到0.02μg/L。本方法灵敏度高,线性范围宽,加标回收率接近100%,能够满足新指令对玩具材料中可迁移六价铬的检测要求。     

高超声速风洞进气道流量系数测量精度影响因素研究

进气道是飞行器动力装置的重要组成部分,准确测量进气道流量系数是进气道风洞试验的重要内容。对来流马赫数Ma=4.5,5.0和6.0状态下皮托管进气道开展流量系数测量研究,通过对比理论值和实测值,获取各状态流量系数修正系数。试验结果表明,随着来流马赫数增加,进气道流量系数与理论值偏差较明显,并逐渐增大。超声速风洞试验通常认为测量截面总温与来流总温相等,通过对测量截面总温与来流总温偏差以及测量截面流场畸变情况的分析,判断测量偏差主要是由测量截面总温等于来流总温的假设导致的。在高超声速风洞试验中,由于模型壁面热交换的存在,测量截面总温低于来流总温,进气道流量系数测量时需要进行总温修正,以提高流量测量精度。      

1 kW微波源机箱电磁耦合的并行FDTD模拟

微波源机箱的不同面板上开有不同数量和大小的矩形孔缝和散热通风孔,电磁脉冲可以通过机箱上的孔缝耦合进入微波源内部,对内部电路和设备造成干扰。通过自动网格剖分技术实现了1 kW微波源的快速建模,采用并行时域有限差分（FDTD）算法模拟了不同极化方向下高斯脉冲正入射1 kW微波源机箱的耦合问题,分析了微波源机箱的电磁脉冲耦合规律。研究结果表明,数值计算结果与电磁软件仿真结果吻合得比较好,电磁脉冲的极化方向对耦合进入微波源箱体内的电场强度影响不大,微波源机箱中心点的谐振特性明显。     

集群企业技术能力构建的案例研究——基于能力矩阵

基于能力矩阵的分析框架,对集群企业的技术能力构建过程和基于OEM关系的超集群知识联系对该过程的影响进行了理论分析。以巴基斯坦的Sialkot集群和我国台湾地区的机床产业集群为案例对象,通过研究两集群中生产商的技术能力构建过程对相关命题进行检验。结论如下:集群企业的技术能力构建是一个多路径过程;基于OEM关系的超集群知识联系对集群企业技术能力构建的作用具有一定局限性;集群企业通过利用这类超集群知识联系开展富于进取心的、积极主动的学习,可以突破该局限性,克服价值链中领导企业设置的障碍,从而可以在更宽的功能范围内构建创新程度更高的技术能力。     

改革以来中国贫困指数的测度与分析

贫困是一个全球性现象,世界各国政府都高度重视解决贫困问题。本文采用拟合收入分布函数的方法计算出改革以来中国城乡以及全国的绝对贫困线、绝对贫困率、相对贫困线、相对贫困率,发现改革以来我国的绝对贫困率快速下降,但目前绝对贫困形势依然不容乐观;相对贫困率则呈现出持续上升的趋势,并与相应的基尼系数变化趋势高度一致;绝对贫困率和相对贫困率的演变过程都与各个时期的经济体制改革进程存在密切的关系。     

基于多层次模糊综合方法的社交媒体营销价值评估研究——以人人网和新浪微博为例

根据卒十交媒体具备营销价值的五个特性,笔者建立了社交媒体的营销价值评估指标体系,进而以新浪微博和人人网为例利用多层次模糊综合方法对这两个网站的营销价值进行了定量评估,最后根据评估结果给出了一些建议。     

地租视角下农村土地承包经营权流转问题研究

针对农村土地承包经营权流转问题的法学研究成果与经济学理论成果相互抵牾的困境,从地租视角揭示农村土地制度演变的内在机理,在对传统地租理论分析的基础上构建一个新的农村土地承包经营权流转地租理论。新地租理论应以农民土地承包经营权有效实现为研究对象,要将制度环境变化作为最重要的实现条件,其核心问题是形成一个完善市场经济体制下的农业用地地租分配体制机制。     

Government ownership,corporate governance and tax aggressiveness: evidence from China

This study investigates how government ownership and corporate governance influence a firm's tax aggressiveness. Using Chinese listed companies during 2003–2009, we find that compared with government‐controlled firms, non‐government‐controlled firms pursue a more aggressive tax strategy. In particular, non‐government‐controlled firms with a higher percentage of the board shareholdings and with a CEO who also serves as the board chairman are more aggressive. For government‐controlled firms, we find that board shareholding has an impact on tax aggressiveness and it does not differ between local and central government‐controlled firms. However, local government‐controlled firms in less developed regions where the implementation of corporate governance measures is generally less effective are more tax aggressive than those in other regions.     

Why Celebrity Sells: A Dual Entertainment Path Model of Brand Endorsement

This article introduces a dual entertainment path model that integrates insights from media entertainment and transportation theory to show how links between entertainment motives (aspirational and playful) and experiences (celebrity fantasy and emotional investment) influence endorsed brand attitude. Results of two studies validate the salience of two paths. Fans, who hold parasocial bond with the celebrity, are driven by both aspirational and playful motives to engage in celebrity-induced entertainment experiences. Nonfans lack aspirational motive and are driven predominantly by playful motive. In either situation, celebrity-induced entertainment experiences enhance endorsed brand attitude. This model complements the existing celebrity endorsement literature by positing entertainment as a salient dimension of brand endorser effects. Its findings provide new insights on how advertisers promote their brands.