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161.
在我国能源安全面临的一系列重大问题中,能源领域的政策规划薄弱,法律保障制度建设与管理体制改革滞后,能源供应与能源安全保障体系缺乏相关政策、法律和制度的保障。只有真正做到政策、法律和管理体制“三位一体”,才能确保国家能源安全。本文从能源安全体系建构的理论和实践出发,借鉴西方能源安全战略实践,从政策、法律和管理体制等角度,对我国能源安全体系的内在机制建构进行分析,旨在为我国与中东能源合作提供借鉴与参考。  相似文献   
162.
完善了商品流通现代化指标体系,并运用模糊综合法将商品流通现代化指标转换成了指数。研究发现商品流通现代化水平与其区域位置、总体经济实力密切相关,且受到产业结构的影响。同时,通过基于指数的聚类分析得到如下结论:"率先发展型区域"要抓住历史机遇,培养创新型人才,保持领先地位;"积极追赶型区域"要发挥地理优势,打破省之间、行业和部门之间、所有制之间的界限,积极参与各种区域经济合作;"流通欠发达型区域"要进一步推进和实施西部大开发战略,推进物流现代化。  相似文献   
163.
Ignored in the flurry of new research on fathers is that fatherhood may have consequences for men. This article explores possible effects on the lives and well‐being of men for a range of fatherhood experiences. Data are drawn from the National Survey of Families and Households. The first part of this article examines whether men's varied associations with children (no children, coresident, non‐coresident, and stepfatherhood) are associated with men's psychological health and behavior, social connections, intergenerational family relations, and work behavior. We found strong evidence that fathers differ from nonfathers in their social connections, family relationships, and work behavior. There is significant variation in effects among the father types as well. The second section of this article focuses attention only on men who are fathers and examines whether fathering behavior (e.g., the amount of time and nature of the activities that fathers are reported to be spending with their children) is associated with men's well‐being. The effects of father involvement on men was found to be most significant for those who were living with their own children.  相似文献   
164.
In 1935, R.A. Fisher published his well-known “exact” test for 2x2 contingency tables. This test is based on the conditional distribution of a cell entry when the rows and columns marginal totals are held fixed. Tocher (1950) and Lehmann (1959) showed that Fisher s test, when supplemented by randomization, is uniformly most powerful among all the unbiased tests UMPU). However, since all the practical tests for 2x2 tables are nonrandomized - and therefore biased the UMPU test is not necessarily more powerful than other tests of the same or lower size. Inthis work, the two-sided Fisher exact test and the UMPU test are compared with six nonrandomized unconditional exact tests with respect to their power. In both the two-binomial and double dichotomy models, the UMPU test is often less powerful than some of the unconditional tests of the same (or even lower) size. Thus, the assertion that the Tocher-Lehmann modification of Fisher's conditional test is the optimal test for 2x2 tables is unjustified.  相似文献   
165.

Age‐specific models of population renewal (with and without feedback) which imply convergence to a stable state for some levels of fertility or feedback may imply the presence of long‐term cycling around a constant or exponentially changing equilibrium for other levels of fertility or feedback. The switch from one regime to the other is a “bifurcation.”; The conditions for bifurcation involve the roots of an analogue of Lotka's Equation.

Typically bifurcation is induced by raising the strength of feedback or the level of fertility. It has been known since the early 1980s, however, that this is sometimes impossible. It is sometimes impossible even with the linear renewal equation itself and with the most basic of non‐linear models, Lee's cohort feedback model.

Here it is proved that this typical route to bifurcation does not fail for these basic models in the presence of a condition which always holds for realistic applications with higher organisms: the existence of a span of ages before the onset of fertility.

Specifically, a strictly positive lower bound on ages of procreation is proved to be sufficient to guarantee the existence of a rescaling of Lotka's Equation for which the real part of some complex root vanishes. This result holds for absolutely Lebesgue‐integrable (signed) net maternity functions on the positive real line and for absolutely summable (signed) net maternities on the positive integers.

It follows that Coale's rescaling device for the analysis of approach to stability in stable population theory can be implemented for all realistic human net maternity schedules. It also follows that the many special cases of the cohort feedback model throughout population biology will all generate persistent cycling instead of stability if feedback is sufficiently strong.  相似文献   
166.
Abstract

The major goal of this presentation is to provide overview of evaluation results of the University of Pittsburgh (Pitt) Faculty and Staff Assistance Program (FSAP). The major goal of the Pitt FSAP evaluation was to generate information pertaining to the program's service adequacy, program effectiveness, client satisfaction, cost-efficiency and cost-savings. Such an evaluation effort is becoming increasingly important due to the recent trend of organizational downsizing and coping with resource constraints. As Universities downsize, it can be challenging to justify allocating scarce funds to employee assistance programming. This study also includes review of EAPs among eighteen universities and colleges from around the country in order to compare program performance of the Pitt FSAP system.  相似文献   
167.
在西方现代化进程中,科学极大地解放了人的智力和体力,为人的自由发展提供了条件。然而,当科学的权威急剧膨胀变异成科学霸权主义,科学成为奴役人的工具时,却造成了人的困境。我国正处于现代化建设的进程中,需要吸收和借鉴西方科学发展进程中的经验和教训,发展一种厚道的、有机的科学具有重要的现实意义。  相似文献   
168.
Consider a random variable S being the sum of a number N of independent and identically distributed random variables Xj (j = 1, 2, ...) where the number N is itself a non-negative integer-valued random variable independent of the Xj An explicit expression of the r-th cumulant of S is given in terms of the cumulants of N and Xj, Asymptotic properties of the distribution of S are also discussed.  相似文献   
169.
王思琦 《西北人口》2012,33(2):89-92
当前中国社会有关70后和80后之间的各种争论层出不穷,主要集中在性观念等道德观的层面,例如,许多人认为80后在性观念上面比70后更为开放,但是缺乏严谨的数据论证。因此,本文使用CGSS(中国综合社会调查)2005年的数据对此进行了分析,发现70后、80后这种基于年龄的代际概念并没有统计上的意义,即在控制相关变量后,这两个年龄阶段群体的性观念开放程度并不存在显著的差异。  相似文献   
170.
A study of 133 full time employees with parent care responsibilities investigated various factors that could reduce this group's future caregiving commitment to aging parents. Study factors included: caregiver attributes, level of caregiving involvement, job stress, tensions between the caregiver and the dependent parent, caregiver's level of physical and mental strain, and limited support from family and friends. The relationship between the caregiver and the parent was the best predictor of sustained commitment to caregiving. One aspect of the employees' work experience made a small, but important contribution to respondents' future care plans. Those employees who frequently adjusted their work schedule and routine to accommodate parent care demands were less likely to sustain their caregiving commitment. Reasons for these findings are explored and implications for social policy and clinical practice are discussed.  相似文献   
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