遗传算法在配送中心选址中的应用

配送中心是现代物流的重要组成部分,它在整个物流系统中起着承上启下的作用,如何合理的选择配送中心就显得尤为关键.本文提出了一种新的二进制和浮点数混合编码的改进遗传算法.该算法对种群初始化函数和遗传操作做相应的改进,使得表示配送中心选址的决策变量只能在0或1这两个离散变量上选择,解码更加方便,大大提高了运算效率,改进的遗传算法能够很好的解决物流配送中心的选址问题.     

Spillovers,integrated production and the theory of the firm

Recent econometric literature has demonstrated the existence of significant technological spillovers within and around groups of advanced (R&D-intensive) firms. I demonstrate thatcompetence blocks of advanced firms operate as technical universities and research institutes, unintentionally providing free educational and research services, often in areas where such services are not supplied by existing educational institutions or where the nature of competence makes traditional educational institutions incapable of supplying them. I demonstrate that the competence that diffuses from such competence blocks is botheconomic andtechnological, that it only diffuses under particular market circumstances, notably characterized by competition, and that the outcomes are typically experimental.Integrated production is an organizational technique to coordinate complex production in mechanical engineering industry within firms and over specialized consultants and subcontractors in the market. Such organizational competence is typically tacit and difficult to communicate outside its production context. Hence, such a production organization often functions as a competence block that spills knowhow throughout the industry. This organizational form is also very useful in illustrating the nature of the firm, the nature of the organizational competence that forms the backbone of western industrial technology and how that competence generates economic growth through the intermediation of firms. I use Swedish aircraft industry as a case illustration.     

Block versus nonblock trading patterns

We investigate the relationship between the number of block (20,000 shares) and nonblock (<5,000 shares) trades over the trading day and across exchanges. In general, for each day of the week, the ratio increases from the first to the second period, declines through the period ending at 3:30 p.m., and increases for the last 30-minute period. Periods with increased small trading activity experience a more than proportionate increase in block trades. Differences across exchanges in the intraday pattern of block trades in relation to smaller trades are reported.     

混凝土小型空心砌块砌体的受剪性能试验研究

本文通过对混凝土小型空心砌体体试件的受剪力学性能试验研究，发现了双排盲孔砌块砌体结构在抗中度上的潜力，并可以解决空心砌块砌体墙体开裂的问题，在试验研究的基础上提出了针对于双排盲孔砌块的抗剪强度的计算公式。可供设计时参考。     

Towards a New Methodology of Estimating Party Policy Positions

In the last twenty years, an international group of political scientists has coded nearly 2000 party manifestos with the help of one single coding scheme based on 56 categories which covers all main topics of these documents. However, there is a growing awareness of the shortcomings of the underlying coding scheme, such as overlapping and missing categories, which cannot be repaired without coding all manifestos all over again. Some have presented an alternative for manifesto-research by means of expert opinions on party policy positions, but these are unable to provide reliable time series for subsequent election years. The unborn solution to some of the problems with the coding scheme would be the computerised content analysis on digitalised party manifestos. This would open up a new universe of infinite possibilities for recodings and reanalyses. The extended consequences from full computerisation of textual analysis are mind boggling. But at the present, these possibilities are merely potentials as the computerised techniques are still underdeveloped. This article explores the possibilities for computerised content analysis in such a way that all postwar manifestos in established democracies can be compared with each other with the help of flexible coding schemes.     

A series of resolvable PBIB(3) designs with two replicates

A new series of resolvable PBIB(3) designs with two replications has been proposed along with a simple method of analysis. These designs form a generalization of circular lattice designs of Rao (1956).     

Question-Answer Sequences in Survey-Interviews

Interaction analysis was used to analyze a total of 14,265 question–answer sequences of (Q-A Sequences) 80 questions that originated from two face-to-face and three telephone surveys. The analysis was directed towards the causes and effects of particular interactional problems. Our results showed that problematic respondent behavior is affected by the questionnaire design, whereas inadequate interviewer behavior is affected by respondent behavior, rather than directly by the questionnaire design. Two surveys used questions for which validating information was available. It appeared that the occurrence of such irregularities of interviewer and respondent behavior was related to the validity of the eventual responses. Explanations for the occurrence of problematic respondent behavior were proposed, concerning both cognitive and conversational factors, related to the wording of questions and response alternatives. Part of this paper was presented at the International Conference on Questionnaire Development, Evaluation and Testing Methods, 14–17 November 2002, Charleston, South Carolina.     

Institutional Investors and Information Asymmetry: An Event Study of Self-Tender Offers

Our research compares the asymmetric information costs of firms with low levels of institutional ownership to those with high levels. We use self‐tender offers as an information event. Our results show that higher institutional ownership, particularly a higher number of institutional investors, is associated with a lower degree of informed trading. These results persist even after we control for differences in trading activity among our sample firms.     

主位“使能”与图式在理解中的互动性

读者理解了篇章的主位"使能"结构,在图式知识指导下,有利于快速、正确划分篇章段落和理解文本大意,实现科学阅读。     

基于邻近值的HEVC帧内预测优化

高性能视频编码(High Efficiency Video Coding,HEVC)标准中的帧内编码模式利用当前帧中像素点之间的空间相关性作出有效预测。为了解决待编码像素远离参考像素时预测不准确的问题,提出了一种基于邻近值的HEVC帧内预测优化算法。该算法的主要思想是,对于当前像素,先根据传统HEVC帧内编码方法得到其预测值,再使用该像素点左边、左上、上边位置的修正值以及该像素本身的预测值对该预测值进行修正。因为将当前像素与周围像素的相关性进行了有效的数学建模,所以HEVC帧内编码性能得到了提升。实验结果显示,所提算法与HEVC标准相比,最高节省了2.7%的码率,平均节省的码率为1.3%。