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361.
本文通过总结民主革命时期和 194 9年中华人民共和国建立后党在农民土地问题上的经验、教训 ,分析了当前京郊农村土地问题的现状 ,并提出了相应的解决对策  相似文献   
362.
陕西水彩艺术的发展步履艰难.客观认识和评价陕西水彩艺术发展的历史和现状,认真总结和分析陕西水彩艺术几十年来发展的特点和优势,正确面对21世纪陕西水彩艺术面临的新问题,将对推动陕西水彩艺术的健康发展至关重要.  相似文献   
363.
In this article we provide a unified framework for solving Dirichlet related probability and waiting time problems. We consider a Pólya sampling scheme in which each time an object is selected, it is put back into the population along with c additional objects of the same type. By considering both fixed sample size and inverse sampling procedures, we unify the Dirichlet I, J, C, and D functions with their hypergeometric counterparts by extending these functions to Pólya sampling. We then use these functions to unify and extend the corresponding expected waiting time results.  相似文献   
364.
Tanaka (1988) lias derived the influence functions, which are equivalent to the perturbation expansions up to linear terms, of two functions of eigenvalues and eigenvectors of a real symmetric matrix, and applied them to principal component analysis. The present paper deals with the perturbation expansions up to quadratic terms of the same functions and discusses their application to sensitivity analysis in multivariate methods, in particular, principal component analysis and principal factor analysis. Numerical examples are given to show how the approximation improves with the quadratic terms.  相似文献   
365.
The moments of the absorption are difficult to obtain. The generating functions are basic hypergeometric functions. This paper shows how to define two shift operators that allow elementary arguments to be used to develop recursions for the expected values of general functions. The exact moments of the distribution follow. The generating function for the negative binomial analogue gives the moments directly.  相似文献   
366.
For the time-homogeneous multi-state Markov chain {Xn,n≧0} with states labeled as "0" (success) and "f"(failure), f=1,2,… the waiting time problems to be discussed arise by setting quotas on runs of success and failures. Some particular cases are considered.  相似文献   
367.
In many linear inverse problems the unknown function f (or its discrete approximation Θ p×1), which needs to be reconstructed, is subject to the non negative constraint(s); we call these problems the non negative linear inverse problems (NNLIPs). This article considers NNLIPs. However, the error distribution is not confined to the traditional Gaussian or Poisson distributions. We adopt the exponential family of distributions where Gaussian and Poisson are special cases. We search for the non negative maximum penalized likelihood (NNMPL) estimate of Θ. The size of Θ often prohibits direct implementation of the traditional methods for constrained optimization. Given that the measurements and point-spread-function (PSF) values are all non negative, we propose a simple multiplicative iterative algorithm. We show that if there is no penalty, then this algorithm is almost sure to converge; otherwise a relaxation or line search is necessitated to assure its convergence.  相似文献   
368.
How does collective leadership within social networks resolve chronic and complex problems common to communities? Unfortunately, sometimes it does not, but when it does, the outcome may be truly extraordinary. We use a case study approach to explain how one Midwest community within the USA applied collective leadership within a community network to reduce teen births. It took ten years of what many identified as provocative media campaigns and comprehensive sex education programs to reduce teen births by 65%, significantly exceeding the stated goal. Using Kotter's change model as a backdrop, powerful strategies and provocative creativity reveal courageous leadership within a social network of diverse people and organizations focused on improving the social well being of their community.  相似文献   
369.
《Social Development》2018,27(3):482-494
Emotional and behavioral maturity expectations increase as children transition to primary school; thus, maternal responses that support and encourage children's expression of negative emotion may not benefit school‐age children as much as preschoolers. The current study explored a change in the utility of these maternal responses among 187 families (62 5‐year‐olds, 75 6‐year‐olds, and 50 7‐year‐olds). Mothers reported on their responses to children's negative emotions and children's externalizing and internalizing behaviors at two time points over 1 year. Multiple group analysis within cross‐lagged path models revealed a positive association between non‐supportive maternal responses and later child externalizing behaviors among 5‐year‐olds. However, non‐supportive responses were related to decreases in externalizing behaviors among the 7‐year‐olds. Discrepant findings between the 5‐ and 7‐year‐olds may represent a developmental shift in the function of mothers' emotion socialization practices.  相似文献   
370.
Individuals differ in their sensitivity toward injustice. Justice‐sensitive persons perceive injustice more frequently and show stronger responses to it. Justice sensitivity has been studied predominantly in adults; little is known about its development in childhood and adolescence and its connection to prosocial behavior and emotional and behavioral problems. This study evaluates a version of the justice sensitivity inventory for children and adolescents (JSI‐CA5) in 1472 9‐ to 17‐year olds. Items and scales showed good psychometric properties and correlations with prosocial behavior and conduct problems similar to findings in adults, supporting the reliability and validity of the scale. We found individual differences in justice sensitivity as a function of age and gender. Furthermore, justice sensitivity predicted emotional and behavioral problems in children and adolescents over a 1‐ to 2‐year period. Justice sensitivity perspectives can therefore be considered as risk and/or protective factors for mental health in childhood and adolescence.  相似文献   
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