4PL模式下基于时间资源调度的供应成本优化研究

订单时间是影响供应成本的主要因素,合理的进行时间资源调度更是供应成本优化的关键所在。现有的第四方物流(Fourth Party Logistics,4PL)路径优化研究只关注物流环节的时间和成本因素,没有与物流上一环节的整合。本文提出将4PL服务拓展到客户的生产环节,在供应商的生产时间窗约束下,构建模型得到生产时间与物流时间的最优组合方案使供应商供应成本最低。最后基于一个实例的分析,验证了该模型能有效帮助4PL为客户提供最优供应方案。     

冻结斜井流砂层段井壁壁后注浆技术的研究与应用

为了提高注浆加固体的承载性能和抗渗性能,本文从井壁壁后注浆技术的角度进行阐述。通过对李家坝煤矿的工程概况和施工现状进行分析,重点研究井壁壁后注浆技术方案与参数,进而为充填井壁、加固围岩提供参考依据。     

建筑幕墙工程的技术要求及质量控制

文章介绍了建筑幕墙工程的结构设计、施工要点及施工质量控制措施,并对其弊端进行了分析,提出了处理措施。     

干挂石材幕墙的设计

干挂石材幕墙是建筑幕墙的一种类型,近年来在国内高层建筑外墙装修中得到广泛应用。结合工程实例,文章从安全施工原则出发,通过对干挂石材幕墙的构造、结构设计、主要材料的选用及其施工工艺等环节进行论述,阐述了干挂石材幕墙深化设计过程。     

荣地水电站增机扩容工程压力钢管的结构设计

荣地水电站增机扩容工程原发电引水系统主要为总长为2663 m的隧洞，由于隧洞竖井至原钢衬段前的钢筋混凝土衬砌施工质量较差，达不到结构安全运行的要求，因此需对原发电引水系统进行加固处理，经方案比选后，采用竖井段进行埋管回填混凝土加固+下平洞内铺设明钢管的方式进行加固处理，并相应对钢管进行结构设计。     

赤水水库塑性混凝土心墙施工技术分析

文章结合塑性混凝土心墙在赤水水库除险加固工程的应用,分析塑性混凝土心墙的施工技术要点。     

Stochastic Dominance Analysis of iShares

Abstract

Country indices as represented by iShares exhibit non-normal return distributions with both skewness and kurtosis. Earlier studies provide procedures for determining the statistical significance of stochastic dominance measures and the Sharpe Ratio. This present study uses these refinements to compare the performance of 18 country market indices. The iShares are indistinguishable when using the Sharpe Ratio as no significant differences are found. In contrast, stochastic dominance procedures identify dominant iShares. Although the results vary over time, stochastic dominance appears to be both more robust and discriminating than the CAPM in the ranking of the iShares.     

基于改进的BP-LM在中国人口老龄化预测中的应用

由于人口老龄化率的预测具有高度非线性特征，这与BP神经网络能够处理非线性问题的特征相符合，但BP神经网络算法易使解陷入局部极小。基于L-M算法的改进BP神经网络可以有效克服这一问题，而且收敛速度快。通过具体的仿真及实践结果验证了改进BP的有效性，并对未来五年的中国老龄化率进行了预测。     

Socio‐demographic factors and shared leadership behaviors in dispersed teams: Implications for human resource management

Companies increasingly make use of geographically dispersed teams to capture knowledge residing at different locations. In this context, shared leadership is considered a key enabler of team performance. Taking a functional perspective on shared leadership, we thus investigate the relationship between shared leadership behaviors and team performance in dispersed teams. Furthermore, we analyze how socio‐demographic factors that are characteristic for dispersed teams (i.e., high female‐to‐male ratio, high mean age, and high levels of national diversity) affect shared leadership behaviors. Based on data from 96 dispersed teams, we show that shared leadership behavior fosters team performance. Further, we find the socio‐demographic characteristics typical for dispersed teams to foster shared leadership. Theoretical and managerial implications for human resource management are discussed. © 2012 Wiley Periodicals, Inc.     

新型外包型钢与粘钢综合加固法

由于业主对建筑结构使用功能的需求,往往在剪力墙开设新的洞口,开洞后将大大降低剪力墙的抗剪能力,对于新建工程可以对剪力墙洞口部位进行增加暗柱、暗梁或加强钢筋来补强剪力墙的抗剪能力。而对于剪力墙开洞改造工程来说,开洞后因无法增加暗梁、暗柱对剪力墙提高承载能力。因此,在开洞后就必须进行加固,现就对传统的加固方法进行分析,并根据实际施工情况提出新的方法。