Discovering non-terminating inputs for multi-path polynomial programs

This paper investigates the termination problems of multi-path polynomial programs （MPPs） with equational loop guards. To establish sufficient conditions for termination and nontermination simultaneously, the authors propose the notion of strong/weak non-termination which under/over- approximates non-termination. Based on polynomial ideal theory, the authors show that the set of all strong non-terminating inputs （SNTI） and weak non-terminating inputs （WNTI） both correspond to tile real varieties of certain polynomial ideals. Furthermore, the authors prove that the variety of SNTI is computable, and under some sufficient conditions the variety of WNTI is also computable. Then by checking the computed SNTI and WNTI varieties in parallel, termination properties of a consid- ered MPP can be asserted. As a consequence, the authors establish a new framework for termination analysis of MPPs.     

广义不确定分布参数系统变结构控制

研究了一类广义不确定分布参数系统的综合问题,由广义不确定分布参数系统的特点,直接给出了变结构控制的设计方法。设计过程简单,控制易于实现,且给出了实例     

Optimum design of equivalent accelerated life testing plans based on proportional hazards-proportional odds model

The optimum design of equivalent accelerated life testing plan based on proportional hazards-proportional odds model using D-optimality is presented.The defined equivalent test plan is the test plan that has the same value of the determinant of Fisher information matrix.The equivalent test plan of step stress accelerated life testing(SSALT) to a baseline optimum constant stress accelerated life testing(CSALT) plan is obtained by adjusting the censoring time of SSALT and solving the optimization problem for each case to achieve the same value of the determinant of Fisher information matrix as in the baseline optimum CSALT plan.Numerical examples are given finally which demonstrate the equivalent SSALT plan to the baseline optimum CSALT plan reduces almost half of the test time while achieving approximately the same estimation errors of model parameters.     

Target estimation using MIMO radar with multiple subcarriers

This paper analyzes the effect of waveform parameters on the joint target location and velocity estimation by a noncoherent multiple input multiple output (MIMO) radar transmitting multiple subcarriers signals. How the number of subcarriers influences the estimation accuracy is illustrated by considering the joint Cramer-Rao bound and the mean square error of the maximum likelihood estimate. The non-coherent MIMO radar ambiguity function with multiple subcarriers is developed and investigated by changing the number of subcarriers, the pulse width and the frequency spacing between adjacent subcarriers. The numerical results show that more subcarriers mean more accurate estimates, higher localization resolution, and larger pulse width results in a worse performance of target location estimation, while the frequency spacing affects target location estimation little.     

基于双库协同机制的KDD*及其软件实现

在KDD(基于数据库的知识发现 )的基础上 ,提出了KDD的开放系统—KDD 的总体结构 ;探讨了其关键技术—双库协同机制的理论基础与实现技术 ;介绍了因果关联规则的统计归纳的发掘方法。初步演示试验的结果表明 ,KDD 这类新型构造是有效与可行的。     

单向关闭三部件串-并联可修系统的可靠性

研究了单向关闭先坏先修三部件串-并联可修系统的可靠性,在假定部件1的失效分布服从可变参数为λ(λ0)的指数分布条件下,利用补充变量法,得到了该系统的瞬时可用度和稳态可用度、系统的可靠度、系统的瞬时和稳态故障频度.     

要素市场一体化对地区全要素生产率的影响

通过测算2011—2020年省级地区的资源错配方向发现,落后地区的资源配置过度,而发达地区处于资源配置不足的状态,因此要素市场一体化意在改善资源错配的现状,提高落后地区边际生产率,并发挥集聚效应促进先进地区全要素生产率的提高。由此,基于我国2008—2019年30个省份的省际面板数据构建计量模型验证该理论假说,结果表明,要素市场一体化在促进先进地区生产率提高的同时,也有助于通过要素的流出对落后地区产生促进作用。作用机制分析显示,促进技术进步与技术效率的提高是要素市场化提升全要素生产率的机制。     

Analysis of network and information security and prevention technology

随着国家经济的持续增长和社会的不断进步,政府部门对信息网络与信息安全提出了更高的要求.文章对当前一些网络信息的不确定性进行分析研究,讨论了主要的防范技术,另外,还对信息资源管理项目中的应用进行了简单的论述.     

双参数指数分布顺序统计量的概率分布性质

设[Xk,1≤k≤n]独立同分布,X（1）≤X（2）≤…≤X（n）为其顺序统计量,当总体服从双参数指数分布exp（μ,σ）时,得到了其顺序统计量的联合概率密度函数和极端顺序统计量的密度函数,进一步得到X（1）和X（n）的期望与方差的表达式.此外还证明了样本间距X（1）,X（2）-X（1）,…,X（n）-X（n-1）独立不同分布,利用样本间距构造一组独立同分布的指数分布exp（1）,借助顺序统计量还构造了x2和F两组概率分布.最后研究了统计量极差Rn=X（n）-X（1）的概率分布.