机器人、微机和微处理器(RMM)的抗干扰

本文讨论了电磁辐射、电源波动等干扰源,并分析这些干扰源怎样引起机器人控制系统、微机、微处理器的失灵和损坏。最后本文介绍了防止这些干扰的实用方法,它们包括有双层屏蔽、光电隔离、光纤传导等方法。     

产业集群企业网络体系:系统建构与结构分析

理论与实践的深入发展迫切要求加强产业集群绩效评价及其比较的定量研究,而集群企业网络体系及其结构分析是集群绩评价的基础和难点。本文运用系统论和社会网络分析工具,对集群企业网络体系系统建构和结构分析做了一个初步的探索性研究,认为集群企业网络体系是集群系统的核心层次,其结构特征可以通过网络密度、网络连通性、群体中心性、小团体结构和规则同型性等变量进行刻画,并具体阐释了各变量的分析方法及其对于集群企业网络分析的意义。     

《世界经济地理》教材编写体系研究

本文从理论上探讨世界经济地理研究的依据和体系,指出现行教材编写存在的问题,提出编写的新建议。认为世界经济地理侧重研究经济区→经济地域→经济地域系统及其运动规律,认为存在世界和国家级区域级别差异。为此,本文认为教材编写时要强调条件要素要与经济地域和经济地域系统形成发展过程一起进行论述,要突出研究对象的等级层次关系,突出城市或城市群的地位与作用,并要加强国家经济国际化进程对经济地域形成发展的影响作用。     

网上CAI

用好现代先进技术,开展网络建设,是教育信息化的第一步。本文基于这一思想,介绍了网上CAI的设计思路,描述了该系统的功能,以及实现系统所采用的技术措施。     

印度妇女的哀歌——浅论《丧宴》的思想性

印度妇女是世界上最为悲惨的妇女,森严的封建礼法制度规定她们处于无权地位———从人格到经济上都得不到独立;而印度特有的封建产物———种姓制度又给她们牢牢地加缚了一条锁链     

用跳马步系列研究奇素数阶规则完美幻方的个数

本文先介绍跳马步系列的有关概念及性质,然后用跳马步系列研究奇素数阶规则完美幻 方的个数。     

On Non-parametric Estimation of the Survival Function with Competing Risks

The non-parametric maximum likelihood estimators (MLEs) are derived for survival functions associated with individual risks or system components in a reliability framework. Lifetimes are observed for systems that contain one or more of those components. Analogous to a competing risks model, the system is assumed to fail upon the first instance of any component failure; i.e. the system is configured in series. For any given risk or component type, the asymptotic distribution is shown to depend explicitly on the unknown survival function of the other risks, as well as the censoring distribution. Survival functions with increasing failure rate are investigated as a special case. The order restricted MLE is shown to be consistent under mild assumptions of the underlying component lifetime distributions.     

Estimation of relaxation time distributions in magnetic resonance imaging

Magnetic resonance imaging techniques can be used to measure some biophysical properties of tissue. In this context, the T₂ relaxation time is an important parameter for soft‐tissue contrast. The authors develop a new technique to estimate the integral of the distribution of T₂ relaxation time without imposing any constraint other than the monotonicity of the underlying cumulative relaxation time distribution. They explore the properties of the estimation and its applications for the analysis of breast tissue data. As they show, an extension of linear discriminant analysis is found to distinguish well between two classes of breast tissue.     

Further results for parallel systems with two heterogeneous exponential components

In this paper, we investigate ordering properties of lifetimes of parallel systems with two independent heterogeneous exponential components with respect to likelihood ratio and hazard rate orders. Two sufficient conditions are provided for likelihood ratio and hazard rate orders to hold between the lifetimes of two parallel systems, respectively. Moreover, we extend the results from exponential case to the proportional hazard rate models. The results established here strength some of the results known in the literature. Finally, some numerical examples are given to illustrate the theoretical results derived here as well.     

Semiparametric estimation of plane similarities: application to fast computation of aeronautic loads

In the big data era, it is often needed to resolve the problem of parsimonious data representation. In this paper, the data under study are curves and the sparse representation is based on a semiparametric model. Indeed, we propose an original registration model for noisy curves. The model is built transforming an unknown function by plane similarities. We develop a statistical method that allows to estimate the parameters characterizing the plane similarities. The properties of the statistical procedure are studied. We show the convergence and the asymptotic normality of the estimators. Numerical simulations and a real-life aeronautic example illustrate and demonstrate the strength of our methodology.