Regional allocation of investment as a hierarchical optimization problem

A new formulation is given for the well-known problem of investment allocation between regions in the framework of a planning model. The case of a dual economy with a Cobb-Douglas production function is worked out in detail with an illustrative numerical example. The corresponding problem for an industrial economy with income disparity between two regions is also discussed.     

浅谈我国企业资本结构的改善和优化

本文针对我国国有企业在经营管理体制转换和结构调整过程中出现的资本结构不合理的问题 ,借鉴现代西方资本结构理论 ,在分析其适用性和现实意义的基础上 ,探讨了我国企业资本结构的影响因素和基本状况 ,提出了改善和优化我国企业资本结构的原则、途径和创新措施等基本策略     

Derivation of a joint occupancy distribution via a bivariate inclusion and exclusion formula

Consider a supply of balls randomly distributed into n distinguishable urns and assume that the number of balls distributed into any specific urn is a random variable with probability function . The joint probability function and binomial moments of the number K_i of urns occupied by i balls each and the number K_j of urns occupied by j balls each, i≠j, given that a total of S_n=m balls are distributed into the n urns, are derived in terms of convolutions of q_x, x=0,1, . . . and their finite differences. Also, some illustrating examples are discussed.     

Percentiles and approximations of the sample median over the sample range for samples of size 3, 5, 7 and 9 from a standard normal distribution

A table of the distribution function of the quotient of sample median and sample range of small samples from the normal distribution is given which is based partly on theoretical results published by L. de H aan and J. T h . R unnenburg , partly on numerical results obtained with Monte Carlo methods. Moreover an approximation of this distribution by Students distributions is introduced.     

针织企业管理信息系统的设计及其优化研究

文章结合开发某针织企业管理信息系统的实践,对企业管理信息系统的设计、实现过程进行了探讨,对其性能的优化进行了必要的研究。该系统的实现产生了较好的经济效益和社会效益。     

Unbiased estimates for a lognormal regression problem and a nonparametric alternative

Given a normal sample with means \({{\bf x}_{1}^{\prime} {\bf \varphi}, \ldots, {\bf x}_{n}^{\prime} {\bf \varphi}}\) and variance v, minimum variance unbiased estimates are given for the moments of L, where log L is normal with mean \({{\bf x}^{\prime} {\bf \varphi}}\) and variance v. These estimates converge to wrong values if the normality assumption is false. In the latter case estimates based on any M-estimate of \({{\bf \varphi}}\) are available of bias \({O\left(n^{-1}\right)}\) and \({O\left(n^{-2}\right)}\). More generally, these are given for any smooth function of \({\left({\bf \varphi}, F\right)}\), where F is the unknown distribution of the residuals. The regression functions need not be linear.     

Investments and the holdup problem in a matching market

This paper studies the properties of the steady state equilibrium in a bilateral matching market with ex ante investments at the market entry stage. Investment incentives depend on search frictions because both parties in a match are partially locked-in when they bargain over the joint surplus from their sunk investments. The associated holdup problem is more important for the long side of the market. In the extreme case of perfectly substitutable investments only the agents on the short side make investments. When market frictions become negligible, the market equilibrium approaches the Walrasian outcome.     

Theory and numerical solution of a discrete queueing problem

Abstract  A queueing problem is considered with one server, independent discrete inter-arrival times, and independent discrete service times. The steady state distribution of the waiting time is approximated by means of the solution of certain linear equations and applying a generalization of the L in -B airstow method for finding quadratic factors of polynomials.     

把北京建成一流的现代化国际城市

本文界定了国际城市的内涵 ;分析了北京发展成国际城市的有利条件和因素 ;认为北京应特别注重软件的建设     

A new procedure for monitoring the range and standard deviation of a quality characteristic

The Shewhart and the Bonferroni-adjustment R and S chart are usually applied to monitor the range and the standard deviation of a quality characteristic. These charts are used to recognize the process variability of a quality characteristic. The control limits of these charts are constructed on the assumption that the population follows approximately the normal distribution with the standard deviation parameter known or unknown. In this article, we establish two new charts based approximately on the normal distribution. The constant values needed to construct the new control limits are dependent on the sample group size (k) and the sample subgroup size (n). Additionally, the unknown standard deviation for the proposed approaches is estimated by a uniformly minimum variance unbiased estimator (UMVUE). This estimator has variance less than that of the estimator used in the Shewhart and Bonferroni approach. The proposed approaches in the case of the unknown standard deviation, give out-of-control average run length slightly less than the Shewhart approach and considerably less than the Bonferroni-adjustment approach.     

物流系统中一类向量优化问题弱有效解集非空紧性的刻画与研究

向量优化问题在物流系统中有着广泛的应用,在向量优化问题中,决策者为了选择一个“最好的”可行方案,需要综合考虑各个目标因素。由于向量优化问题的解和决策者的偏好紧密联系,所以最优解的概念在这里是没有意义的。通常研究的是有效解和弱有效解。它们和决策者的控制结构密切相关。文章研究了当目标空间的控制结构为多面体锥时,锥约束凸向量优化问题的弱有效解集的非空紧性的各种刻画,从而为向量优化问题计算方法的发展提供了很好的理论基础。     

A different solution of a problem posed by Theil and Schweitzer

De vraag naar de nauwkeurigste (d.i. kleinste tweede moment) schatter van de restvariantie a² bij lineaire regressieanalyse met isomore onafhankelijke normaal verdeelde residuen wordt opnieuw beantwoord, maar longs vrijwel geheel andere weg dan door THEIL en SCHWEITZER [3] bewandeld. Het blijkt bovendien dat deling van de residuele som van kwadraten door het bijbehorende aantal vrijheids-graden + 2 niet alleen in de klasse der kwadratische funk ties der waarnemingen maar zelfs in de klasse van alle veelvouden van zuivere schattingen van σ² de nauwkeurigste is. Gebruik wordt gemaakt van de in een appendix bewezen stelling, dat de traditionele schatter van σ², waarbij de residuele som van kwadraten door het bijbehorend aantal vrijheidsgraden wordt gedeeld, de nauwkeurigste is onder alle zuivere schatters.     

某驱动桥半轴套管断裂分析和优化设计

后桥是汽车的关键零部件,起着承受载荷和扭矩的作用,一旦出现断裂,将严重影响乘客的生命安全,故对其失效模式分析尤为重要。本文对一款新型后桥在道路试验过程中发生半轴套管断裂的失效模式进行分析,通过材质检测及理论计算,对失效因素进行排查。最终找到失效原因,并提出改进措施,避免再次失效,对提高汽车的安全性意义重大。     

Defining and measuring the development of a country over time: a proposal of a new index

This paper introduces the concept of harmonic growth as an extended acceptation of the notion of development, and discusses its measurement via the Harmonic Growth Index (HGI). The growth is seen as harmonic when the behaviour of a benchmark time series, which here is a measure of wealth, such as per capita GDP, is followed by a similar pattern in socio-economic series. Unlike most widely used indicators in the literature, which take into account the measurement of development over a single time, HGI measures the degree to which a social indicator’s time series pattern matches with the GDP’s. The index is a function, ranging in [0, 1], of the coefficients of the uniform B-splines fitted to each time series, according to the functional data framework. A case study on Mediterranean welfare countries (Greece, Italy, Portugal, and Spain), in the period 1996–2007, shows critical differences in the selected indicators which can be ascribed to their dissimilar specific development models. HGI can be also considered as a general index to measure the similarity between time patterns, or as an alternative to correlation for (non-necessarily linear) time series.     

Implementing structure and control over unofficial inventories in a multispecialty group practice

Materiel managers have been in control of most aspects of the supply chain except for the inventories of the end users, which account for 70 percent of the inventory supply dollars. When the Materials Manager at Lexington Clinic in Lexington, Kentucky, was approached by the Clinic's Chief Executive Officer to implement cost containment measures, the Materials Manager seized the opportunity to implement a six-step program aimed at controlling those supply dollars. Through requisition training, enforcing approval levels, limiting the number of requisitioners, and establishing par levels on floor inventories, the clinic's "unofficial" inventory supply dollars were reduced by 7 percent in the first 12 departments where the par levels were established. The program was hailed as a tremendous success and a positive experience for everyone, from nurses to warehouse clerks.     

Religious pluralism and religious participation: a median-based approach to the non-substantive problem

Sociologists of religion have long been interested in the interaction between religious pluralism and religious vitality. Previous empirical studies approach this theme by drawing on data of denominational participation rates across geographical units, investigating the property of association between the quantity of one minus the Herfindahl–Hirschman Index (religious pluralism), and the total religious participation rate (religious vitality). However, this association could be theoretically spurious. Taking advantage of the median’s statistical property of being less sensitive to the variations of extreme values, this study proposes to apply the median instead of the arithmetic summation of religious participation rates to measure geographical-unit-level religious vitality. This method is illustrated by analyzing the New York State census of religion 1865 and the U.S. county survey 1990.