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41.
姜冷 《辽宁工程技术大学学报(社会科学版)》2012,(4):396-399
为了进一步提高高校学报出版活动效率,采用项目管理的方法对高校学报出版活动进行研究。分析了高校学报项目化管理的可行性。针对高校学报出版发行活动,制定了一套切实可行的操作计划,运用WBS方法对学报出版项目工作进行层层分解,项目责任矩阵图将所分解的工作落实到有关部门或个人。为确保能够在规定的时间内实现期刊出版项目的目标,编制了学报出版项目的甘特图,利用Project软件对现有人力资源和进度进行调配,使学报出版工期在原来50天的基础上缩短了16天。可见通过运用科学的项目管理工具对高校学报出版发行活动进行管理,使得高校学报管理工作更加规范化、科学化。 相似文献
42.
研究了PD+n及PS+n两类广义正定矩阵的某些基本性质,给出两矩阵的Kronecker积与Hadamard积为PD+n类广义正定矩阵的充要条件,修正了已有结论 相似文献
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44.
孔子“出妻”说及相关问题 总被引:1,自引:1,他引:0
历代学者多认为孔子"出妻",儒家不重视婚姻家庭,这严重影响了人们对孔子生活实际的认识,甚至导致人们对孔子的学说产生怀疑。实际上,《礼记》、《仪礼》、《孔子家语》等典籍的相关记载,并没有所谓孔子"出妻"之事说,所谓"孔氏三世出妻说"、"四世出妻说"也不符合历史事实。儒家十分重视婚姻家庭的和睦对治理社会的重要作用。 相似文献
45.
In this note we provide a counterexample which resolves conjectures about Hadamard matrices made in this journal. Beder [1998. Conjectures about Hadamard matrices. Journal of Statistical Planning and Inference 72, 7–14] conjectured that if H is a maximal m×n row-Hadamard matrix then m is a multiple of 4; and that if n is a power of 2 then every row-Hadamard matrix can be extended to a Hadamard matrix. Using binary integer programming we obtain a maximal 13×32 row-Hadamard matrix, which disproves both conjectures. Additionally for n being a multiple of 4 up to 64, we tabulate values of m for which we have found a maximal row-Hadamard matrix. Based on the tabulated results we conjecture that a m×n row-Hadamard matrix with m?n-7 can be extended to a Hadamard matrix. 相似文献
46.
《Women and birth : journal of the Australian College of Midwives》2015,28(2):154-159
BackgroundTraditional and gestational surrogate mothers assist infertile couples by carrying their children. In 2005, a meta-analysis on surrogacy was conducted but no study had examined empathy and maternal–foetal attachment of surrogate mothers. Assessments of surrogate mothers show no sign of psychopathology, but one study showed differences on several MMPI-2 scales compared to a normative sample: surrogate mothers identified with stereotypically masculine traits such as assertiveness and competition. They had a higher self-esteem and lower levels of anxiety and depression.Research objectiveTo determine if there is a difference in empathy and maternal–foetal attachment of surrogate mothers compared to a comparison group of mothers.MethodsThree groups of European traditional and gestational surrogate mothers (n = 10), Anglo-Saxon traditional and gestational surrogate mothers (n = 34) and a European normative sample of mothers (n = 32) completed four published psychometric instruments: the Interpersonal Reactivity Index (empathy index), the Hospital Anxiety and Depressions Scale and the MC20, a social desirability scale. Pregnant surrogate mothers filled the Maternal Antenatal Attachment Scale (n = 11). Statistical non-parametric analyses of variance were conducted.FindingsDepending on cultural background, surrogate mothers present differences in terms of empathy, anxiety and depression, social desirability and quality of attachment to the foetus compared to a normative sample.ConclusionsEnvironment plays a role for traditional and gestational surrogacy. Surrogate mothers of both groups are less anxious and depressed than normative samples. Maternal–foetal attachment is strong with a slightly lower quality of attachment. Surrogate mother's empathy indexes are similar to normative samples, sometimes higher. 相似文献
47.
Here we consider an exponentiated version of the reduced Kies distribution and discuss some of its properties. The parameters of the distribution are estimated by the method of maximum likelihood and illustrated with the help of certain real-life data sets. Asymptotic behavior of the maximum likelihood estimators of the parameters of the distribution is also studied by using certain simulated data sets. 相似文献
48.
It is well known that in finance variances and covariances of asset returns move together over time. Recently, much interest has been aroused by an approach involving the use of the realized covariance (RCOV) matrix constructed from high-frequency returns as the ex-post realization of the covariance matrix of low-frequency returns. For the analysis of dynamics of RCOV matrices, we propose the generalized conditional autoregressive Wishart (GCAW) model. Both the noncentrality matrix and scale matrix of the Wishart distribution are driven by the lagged values of RCOV matrices, and represent two different sources of dynamics, respectively. The GCAW is a generalization of the existing models, and accounts for symmetry and positive definiteness of RCOV matrices without imposing any parametric restriction. Some important properties such as conditional moments, unconditional moments, and stationarity are discussed. Empirical examples including sequences of daily RCOV matrices from the New York Stock Exchange illustrate that our model outperforms the existing models in terms of model fitting and forecasting. 相似文献
49.
The paper entitled “Bivariate and Multivariate Normal Characterizations: A Brief Survey,” by Hamedani, which was published in 1992, covered the published characterizations of bivariate and multivariate normal (MVN) distributions from 1941 to 1991. The present work is a follow-up to the 1991/1992 survey which includes not only characterizations of the bivariate and MVN distributions, but also characterizations of the matrix variate normal distribution, which have appeared from 1991/1992 to the present. 相似文献
50.
We study a system of two non-identical and separate M/M/1/? queues with capacities (buffers) C1 < ∞ and C2 = ∞, respectively, served by a single server that alternates between the queues. The server’s switching policy is threshold-based, and, in contrast to other threshold models, is determined by the state of the queue that is not being served. That is, when neither queue is empty while the server attends Qi (i = 1, 2), the server switches to the other queue as soon as the latter reaches its threshold. When a served queue becomes empty we consider two switching scenarios: (i) Work-Conserving, and (ii) Non-Work-Conserving. We analyze the two scenarios using Matrix Geometric methods and obtain explicitly the rate matrix R, where its entries are given in terms of the roots of the determinants of two underlying matrices. Numerical examples are presented and extreme cases are investigated. 相似文献