美国空军卫星控制网的现状与发展趋势

近几年的几场局部战争部分表明了现代军事航天系统的重要性。本文主要介绍了美国最重要的一个军事航天测控网－－空军卫星控制网的情况，希望能对了解美国军事航天测控体制有所帮助。     

Asymmetric performance: the market share impact of scale and link alliances in the global auto industry

This study investigates how participating in strategic alliances with rivals affects the relative competitive positions of the partner firms. The paper builds on studies that show significant differences in the outcomes of scale and link alliances. The study argues that the more asymmetric outcomes of link alliances translate into greater changes in the relative market shares of the partner firms, due to unbalanced opportunities for inter‐partner learning and learning by doing. We find support for this argument by examining 135 alliances among competing firms in the global automobile industry, from 1966 to 1995. Copyright © 2004 John Wiley & Sons, Ltd.     

Stability and Segregation in Group Formation

This paper presents a model of group formation based on the assumption that individuals prefer to associate with people similar to them. It is shown that, in general, if the number of groups that can be formed is bounded, then a stable partition of the society into groups may not exist. (A partition is defined as stable if none of the individuals would prefer be in a different group than the one he is in.) However, if individuals' characteristics are one-dimensional, then a stable partition always exists. We give sufficient conditions for stable partitions to be segregating (in the sense that, for example, low-characteristic individuals are in one group and high-characteristic ones are in another) and Pareto efficient. In addition, we propose a dynamic model of individual myopic behavior describing the evolution of group formation to an eventual stable, segregating, and Pareto efficient partition. Journal of Economic Literature Classification Numbers: C72, H41.     

The adequacy of asymptotic approximations in the near-integrated autoregressive model with dependent errors

We consider the normalized least squares estimator of the parameter in a nearly integrated first-order autoregressive model with dependent errors. In a first step we consider its asymptotic distribution as well as asymptotic expansion up to order O_p(T⁻¹). We derive a limiting moment generating function which enables us to calculate various distributional quantities by numerical integration. A simulation study is performed to assess the adequacy of the asymptotic distribution when the errors are correlated. We focus our attention on two leading cases: MA(1) errors and AR(1) errors. The asymptotic approximations are shown to be inadequate as the MA root gets close to −1 and as the AR root approaches either −1 or 1. Our theoretical analysis helps to explain and understand the simulation results of Schwert (1989) and DeJong, Nankervis, Savin, and Whiteman (1992) concerning the size and power of Phillips and Perron's (1988) unit root test. A companion paper, Nabeya and Perron (1994), presents alternative asymptotic frameworks in the cases where the usual asymptotic distribution fails to provide an adequate approximation to the finite-sample distribution.     

弱势群体就业扶持政策研究

分析了当前我国弱势群体失业情况的严重性、特殊性及其原因 ,提出了构建我国弱势群体扶持政策的基本原则及标本兼治、着眼未来的就业扶持政策     

物业税的开征对房地产市场的调控作用

从长期看,房价会随着经济的增长而增长。但我国房价近年来每年以30%～50%的速度增长肯定是有问题的。高房价成了目前中国社会各种矛盾的焦点之一。政府可以通过法律与制度来调整目前国内房地产市场严重的利益不均衡。而税收政策就是其中不可或缺的工具。文中从物业税设置的必要性、可行性等方面加以论述,讨论了物业税开征对房价的调控作用。     

Three Corrected Score Tests for Generalized Linear Models with Dispersion Covariates

We develop three corrected score tests for generalized linear models with dispersion covariates, thus generalizing the results of Cordeiro , Ferrari and Paula (1993) and Cribari-Neto and Ferrari (1995) . We present, in matrix notation, general formulae for the coefficients which define the corrected statistics. The formulae only require simple operations on matrices and can be used to obtain analytically closed-form corrections for score test statistics in a variety of special generalized linear models with dispersion covariates. They also have advantages for numerical purposes since our formulae are readily computable using a language supporting numerical linear algebra. Two examples, namely, iid sampling without covariates on the mean or dispersion parameter oand one-way classification models, are given. We also present some simulations where the three corrected tests perform better than the usual score test, the likelihood ratio test and its Bartlett corrected version. Finally, we present a numerical example for a data set discussed by Simonoff and Tsai (1994) .     

对智能建筑规范化操作的思考

作通过对数项目程中的弱电工程的监理经验总结，提出了对智能建筑实行规范化操作的具体建议。     

土地流转：弱转入土地意愿的博弈分析

[目的]我国土地制度的施行使得农户拥有较多小块土地,家庭农场实现连片规模经营的前提是获得规模连片土地,家庭农场与农户进行土地流转协商时,农户将土地流转给家庭农场的意愿如何值得探讨。因此本文研究目的是对家庭农场实现规模连片生产提出建议,期望家庭农场实现规模化经营。[方法]博弈分析法。[结果]家庭农场存在从农户手中转入土地困难,转入土地意愿不强的现象,家庭农场弱转入土地意愿的根源在于土地租金过低、农户转出土地净利润过低、实际转入土地意愿过低。[结论]由此文章提出了3点建议:(1)尝试"确权不确地,确地不确人"的确权政策(2)创建农村土地经营权流转信息平台,建立农村土地流转交易所(3)工商资本下乡租田的做法需谨慎。     

一种基于DS-FFH/MSK调制的数据链抗干扰性能分析

提出了DS-FFH/MSK调制方式的一种实现方案,并在多种干扰环境下,从信源误比特率的角度对基于该实现方案的Link16战术数据链的抗干扰性能进行了系统分析,推导了几种不同干扰条件下数据链的误比特率表达式,并给出了计算机仿真结果.