企业流程再造中标杆瞄准理论及其应用

本文从企业流程再造BPR思想出发,对标杆瞄准理论Benchmarking进行了研究,论述了标杆瞄准理论的基本原理和思想,同时结合中国某航空动力机械公司的南方125摩托车装配系统管理的实例,针对如何选择标杆瞄准对象、如何合理运用问卷调查和直接访问、如何选择关键流程确定绩效衡量指标以及如何确定框架结构进行优化组合,提出了一套标杆瞄准的具体实施方法。     

Exact Bayesian modeling for bivariate Poisson data and extensions

Bivariate count data arise in several different disciplines (epidemiology, marketing, sports statistics just to name a few) and the bivariate Poisson distribution being a generalization of the Poisson distribution plays an important role in modelling such data. In the present paper we present a Bayesian estimation approach for the parameters of the bivariate Poisson model and provide the posterior distributions in closed forms. It is shown that the joint posterior distributions are finite mixtures of conditionally independent gamma distributions for which their full form can be easily deduced by a recursively updating scheme. Thus, the need of applying computationally demanding MCMC schemes for Bayesian inference in such models will be removed, since direct sampling from the posterior will become available, even in cases where the posterior distribution of functions of the parameters is not available in closed form. In addition, we define a class of prior distributions that possess an interesting conjugacy property which extends the typical notion of conjugacy, in the sense that both prior and posteriors belong to the same family of finite mixture models but with different number of components. Extension to certain other models including multivariate models or models with other marginal distributions are discussed.     

中国知识界对议会政治的认知与民国政制的演变

中国人对于议会政治的认识深深影响着民国政制的演化。“议会救国论”、“议会万能论”是清末思想界的主流 ,章太炎、孙中山等则已对议会政治有所批评。民国初年移植议会政治体制引发种种弊端 ,使中国知识界议会观发生逆转 ,“议会破产论”论、“议会过时论”兴盛一时 ,不少人一方面关注西方改造代议制的新趋势 ,一方面反思中国传统政治制度可以古为今用之处 ,提出改造代议制的各色方案。南京政府抛弃议会政治的外壳、试行党治失败的同时 ,西方改造代议制的浪潮也已暴露出问题 ,人们开始进入对于改造代议制的反思期 ,“重回代议制”成为 2 0世纪三四十年代宪政运动的主题。中国知识界的议会观的演变遵循着制度决定论与实用主义逻辑 ,社会进化论与理性主义崇拜则是其哲学基础。民主观念的激进化 ,是中国移植西式民主制度失败的思想原因之一     

Optimal two treatment repeated measurement designs for three periods

Repeated Measurement Designs, with two treatments, n (experimental) units and p periods are examined, the two treatments are denoted A and B. The model with independent observations within and between treatment sequences is used. Optimal designs are derived for: (i) the difference of direct treatment effects and the difference of residual effects, (ii) the difference of direct treatment effects, and (iii) the difference of residual effects. We prove that for three periods when n is odd the optimal design in the three cases (i), (ii), and (iii) is determined by taking the sequences BAA and ABB in numbers differing by one. If n is even, the optimal design in cases (i), (ii), and (iii) is again the same, by taking the sequences ABB and BAA in equal numbers. In case (i), for n even or odd, in the optimal design there is no correlation between the two estimated parameters. For n even, case (i) was solved by Cheng and Wu in 1980. The above imply that with two treatments in practice are preferable to use three periods instead of two.     

Victimization, Psychological Distress and Subsequent Offending Among Youth

The current study examined the relationship between the victimization of youth, psychological distress and subsequent offending. It examined whether direct and vicarious victimization by exposure to violence in the family, among peers, and in the neighborhood, significantly predicted psychological distress among study participants and whether psychological distress significantly predicted subsequent offending over time. In addition, it examined the extent (if any) to which psychological distress mediated the relationship between victimization and subsequent offending. Method: study data are from wave 1 and wave 2 of the Buffalo Longitudinal Study of Young Men (BLSYM), a population based sample (n = 625) of young men, ages 16-19 years old in a metropolitan area of Buffalo, New York. A path analytic approach was used for the main analyses. Findings: personal, vicarious victimization by exposure to violence among peers, and perception of neighborhood safety were significant predictors of offending at wave 1. Personal and property victimization was significant predictors of psychological distress. Psychological distress did not have a significant relationship with offending at wave 1 yet, it did at wave 2. Vicarious victimization by exposure to violence among peers and offending at wave 1 were all significant predictors of offending at wave 2. The results highlight the need to respond to both direct and vicarious victimization among young males to reduce psychological distress and subsequent offending.     

Cohorts,education, and the evolution of tolerance

Normative and social structural explanations for changes in tolerance are tested using racial attitude items from 11 surveys between 1958 and 1978. Over the 20 years, while there were changes in the overall levels of racial tolerance, there were also changes in the upper and lower ends of a tolerance spectrum which differentially depended on cohort and educational effects. Regardless of the position in the tolerance spectrum, most of the change in racial attitudes resulted from across-the-board changes in all cohort and educational groups. The most racially conservative end of the spectrum was slightly eroded by increased educational attainment in the population, while the most racially liberal position was somewhat advanced by cohort replacement. In the final analysis, the normative perspective demonstrated the greater potential for applications to other, more complex, configurations of tolerance.     

火电站直接空冷系统及其空冷器的热力计算

本文叙述了电站汽轮机排汽在空冷凝汽器中直接对空气放热而冷凝的直接空冷系统,并着重研究了空冷凝汽器的原理、结构布置及其热力计算方法。     

直通通信技术研究

在超级并行处理、人工神经网络和分布式计算机等系统中，在任意两结点间建立无需中间节点参与的直接的物理通路，实现消息的直接传输，将彻底解决这些系统中结点间通信的大时延问题。这种被称为直通的技术将为这些系统的研究和开发提供强有力的支持     

对转式永磁无刷直流电机无位置检测控制策略研究

研究对转式永磁无刷直流电机基于反电势过零点的无位置传感器控制策略,通过理论推导和实验验证该策略能够运用于对转式永磁无刷直流电机。针对静止状态下启动困难问题,基于d轴正向增磁、反向去磁导致铁芯饱和程度不同而产生电感差异及q轴到d轴之间电感差异的原理,提出了一种通过施加6个短时电压脉冲即可判断磁极转子初始位置的检测方法,以及施加2个短时导通相电压脉冲获得换相时刻的启动加速方法,并进行实验验证。结果表明：基于电感差异原理提出的磁极转子初始位置检测和启动方法能够有效解决启动困难题,扩大了对转式永磁无刷直流电机的运用范围,提高对转式永磁无刷直流电机无位置检测控制性能。