The Effect of Expected Income on Individual Migration Decisions

This paper develops a tractable econometric model of optimal migration, focusing on expected income as the main economic influence on migration. The model improves on previous work in two respects: it covers optimal sequences of location decisions (rather than a single once‐for‐all choice) and it allows for many alternative location choices. The model is estimated using panel data from the National Longitudinal Survey of Youth on white males with a high‐school education. Our main conclusion is that interstate migration decisions are influenced to a substantial extent by income prospects. The results suggest that the link between income and migration decisions is driven both by geographic differences in mean wages and by a tendency to move in search of a better locational match when the income realization in the current location is unfavorable.     

大学科技园建设基本路径：创新、转型、应用

通过比较国内一些先进大学科技园的成功建设经验,针对河南省大学科技园建设现状和存在的主要问题,提出加强大学科技园建设与发展的基本路径：创新、转型、应用。     

省略和倒置在科技英语中的应用

通过科技英语词汇和句法的应用,探讨了科技英语由于信息量很大,需要用省略和倒置的方法以突出传递的信息,指出在科技英语翻译中,应注意修饰和被修饰成分之间的上下文逻辑关系。只有正确的理解原文,才能准确客观地翻译出原文的信息。     

我国农民科技文化素质偏低的原因与对策

我国农民科技文化素质整体上偏低,与我国传统的重政轻技观念、小农生产方式及城乡二元结构是密切相关的。农村教育、培训机制、法律不健全,也影响了农民科技文化素质的提高。要加强科技宣传推广工作,加大对农村教育的投入,加强制度和法律建设,积极引进项目,通过多种渠道提高农民的科技文化素质。     

建国以来党的科技思想的发展脉络

中国共产党将马克思主义科技思想与中国具体实际相结合,逐步探索出适合中国国情的科技思想,创立了中国化的马克思主义科技思想。通过对建国60多年科技发展历史轨迹的探寻,从科技价值、科技战略、科技政策和科技人才的维度,系统梳理了建国以来党的科技思想的发展脉络,从而揭示出中国特色社会主义科技思想的真实图景。     

钱学森现代科学技术体系的重要意义

钱学森提出了社会主义建设的总体结构,总结了科学技术的发展历程及其对社会发展的巨大推动作用,进一步深化了"生产力是人类全部历史的基础"的观点。他建议建立科学技术业,并将其作为新产业革命带来的第四产业。同时,他坚持要开展以系统科学为理论基础的社会系统工程建设。此外,根据我国科学技术与国防建设的经验,他用系统的理论与方法,建立起了具有中国特色的系统工程理论。他在社会主义国家学方面也做出了突出的贡献。     

基于Tabu搜索方法的配电网重构的一种新方法

配电网重构是一个组合优化问题,它不仅是配电系统循环控制的重要方法,也是配电管理系统的重要组成部分.随着智能技术的不断发展,用智能算法解决组合优化问题成为一种可能.在配电网重构时,当以最小开关操作程度作为目标函数就可转化为线性规划问题;以最小网损为目标函数,可转化为混合整数线性规划问题.基于配电线路重构模型,以最小开关操作程度和最小网损为目标函数,用Tabu搜索方法解决组合优化问题,最后验证了此方法的合理性和可用性.     

A reactive tabu search algorithm for the vehicle routing problem with simultaneous pickups and deliveries

The vehicle routing problem with pickups and deliveries (VRPPD) extends the vehicle routing problem (VRP) by allowing customers to both send and receive goods. The main difficulty of the problem is that the load of vehicles is fluctuating rather than decreasing as in the VRP. We design a reactive tabu search metaheuristic that can check feasibility of proposed moves quickly and reacts to repetitions to guide the search. Several new best solutions are found for benchmark problems.     

北京高校毕业生求职的资源动员行为分析

本文依据北京高校毕业生的实证调研数据,分析了大学生求职资源动员行为的结构与特征。研究发现:动员校内资源是中国大学生重要的求职行为;在所属高校层级、自身校内资源和生源地等指标上,不同毕业生群体的资源动员行为存在显著性差异。     

Lower bounds and a tabu search algorithm for the minimum deficiency problem

An edge coloring of a graph G=(V,E) is a function c:E→ℕ that assigns a color c(e) to each edge e∈E such that c(e)≠c(e′) whenever e and e′ have a common endpoint. Denoting S _v (G,c) the set of colors assigned to the edges incident to a vertex v∈V, and D _v (G,c) the minimum number of integers which must be added to S _v (G,c) to form an interval, the deficiency D(G,c) of an edge coloring c is defined as the sum ∑ _v∈V D _v (G,c), and the span of c is the number of colors used in c. The problem of finding, for a given graph, an edge coloring with a minimum deficiency is NP-hard. We give new lower bounds on the minimum deficiency of an edge coloring and on the span of edge colorings with minimum deficiency. We also propose a tabu search algorithm to solve the minimum deficiency problem and report experiments on various graph instances, some of them having a known optimal deficiency.