基于RPi的面曝光快速成形机控制系统

为了简化面曝光快速成形机的控制系统,降低其成本,提出了一种基于树莓派( Raspberry Pi,RPi)卡片电脑的面 曝光快速成形机控制系统。系统以Raspberry Pi为控制核心,以Linux为操作系统,通过Pvthon编程控制,实现了对面曝 光快速成形机的掩模图形投影和工作台运动控制;利用接入以太网的Raspberry Pi,实现了对面曝光快速成形机的远程 登录、文件传输以及实时监控。控制系统大大减小了面曝光快速成形机的占用空间,降低了成本,且具备远程操作功能, 有利于面曝光快速成形机进入大众市场。     

有关P_B~⊥P_A、P_A~⊥P_B的矩阵等式和秩等式

在M=(A B)中,令A1=P⊥BPA,B1=P⊥APB,利用投影算子理论和矩阵秩方法可以得到关于A1,B1的一些矩阵等式和秩等式.     

国家自然科学基金资助项目综合评价:基于Vague 集多准则决策

采用基于Vague 集的多准则决策方法,对国家自然科学基金11 类主要竞争性资助项目的实施情况进行综合评价和排序． 首先,通过问卷调研的方式,由国家自然科学基金项目评审专家采用“高”、“不高”和“不清楚”三类语义,对各类项目按照“评审公正性”、“管理规范性”、“科研创新性”和“社会影响力”四个准则进行评价; 然后,根据问卷统计结果,将语义评价转化为Vague 估计值,并利用一种新的评分函数计算各类项目在各准则下的得分; 最后,采用正态分布的OWA 算子集结各准则下的得分,得到所有项目的综合评价和排序． 本文的研究结果将为完善国家自然科学基金的资助结构与管理模式提供重要参考依据．     

《竹取物语》对中国嫦娥奔月的接受及化用

在《竹取物语》结尾部分,女主人公赫夜姬穿上羽衣、服下不死药随来使升入月宫,这一情节的设置与“不死药”等字眼不难让人联想到中国的嫦娥奔月传说。但是,《竹取物语》并非对中国嫦娥奔月的全盘接受,而且在主人公身份地位、不死药获得手段等方面具有不同于嫦娥奔月的鲜明特征。本文拟通过文本解读的方法,就《竹取物语》对中国奔月神话的接受及化用进行探讨,并从奔月情节的设置来分析《竹取物语》的结构与主题,从而探明《竹取物语》引用奔月情节的意义所在。     

Error reduction in density estimation under shape restrictions

For the problems of nonparametric estimation of nonincreasing and symmetric unimodal density functions with bounded supports we determine the projections of estimates onto the convex families of possible parent densities with respect to the weighted integrated squared error. We also describe the method of approximating the analogous projections onto the respective density classes satisfying some general moment conditions. The method of projections reduces the estimation errors for all possible values of observations of a given finite sample size in a uniformly optimal way and provides estimates sharing the properties of the parent densities.     

具反射边界条件的板模型迁移系统的临界性

研究非均匀介质,各向同性,具反射边界条件的板模型迁移系统的临界解.借助泛函分析方法,特别是Lp空间上的线性算子理论,证明了积分算子的主本征值(即临界参数)的性质,并获得了系统处于次临界状态的条件以及使系统处于临界状态的板厚度的存在性.     

Pseudo Self-Consistent Estimation of a Copula Model with Informative Censoring

Abstract.  We consider the case where a terminal event censors a non-terminal event, but not vice versa. When the events are dependent, estimation of the distribution of the non-terminal event is a competing risks problem, while estimation of the distribution of the terminal event is not. The dependence structure of the event times is formulated with the gamma frailty copula on the upper wedge, with the marginal distributions unspecified. With a consistent estimator of the association parameter, pseudo self-consistency equations are derived and adapted to the semiparametric model. Existence, uniform consistency and weak convergence of the new estimator for the marginal distribution of the non-terminal event is established using theories of empirical processes, U -statistics and Z -estimation. The potential practical utility of the methodology is illustrated with simulated and real data sets.     

企业经营者业绩考核可持续发展指标体系研究

现行企业经营者业绩评价模式大都忽视环境问题,时间跨度较短,仅仅看年度利税或销售额等指标,这显然与可持续发展的要求不相适应。为此,建立一套评价企业经营者业绩考核的可持续发展指标体系很有必要。文章以此为基础提出了设置企业经营者业绩考核的可持续发展指标体系的原则,构建出企业经营者业绩考核的可持续发展指标体系。     

Conditional Functional Principal Components Analysis

Abstract.  This work proposes an extension of the functional principal components analysis (FPCA) or Karhunen–Loève expansion, which can take into account non-parametrically the effects of an additional covariate. Such models can also be interpreted as non-parametric mixed effect models for functional data. We propose estimators based on kernel smoothers and a data-driven selection procedure of the smoothing parameters based on a two-step cross-validation criterion. The conditional FPCA is illustrated with the analysis of a data set consisting of egg laying curves for female fruit flies. Convergence rates are given for estimators of the conditional mean function and the conditional covariance operator when the entire curves are collected. Almost sure convergence is also proven when one observes discretized noisy sample paths only. A simulation study allows us to check the good behaviour of the estimators.     

含导数项的p-Laplacian算子多点边值问题三个正解的存在性

利用Leggett-Williams不动点定理的一个扩展定理,研究了非线性项含导数项的pLapla-cian算子多点边值问题,得到了三个正解存在的充分条件.