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391.
The utility of conventional project management techniques, such as PERT and CPM, is hampered by significant and realistic network attributes and managerial considerations. There are many situations which involve more than one project and numerous resources. Of major concern in such situations is the reduction of the maximum quantity of each required resource. The algorithm presented here is capable of scheduling the individual activities in multiple projects with multiple resources and leveling the overall quantity of each resource which is required. The basis of the algorithm is a sequencing procedure for examining various combinations of activity start times. The measure of effectiveness for each combination is the sum of the squares of the required quantity of each resource in each time period. 相似文献
392.
本文介绍了蒙古尔部族的组成、形成和发展,并对其族长、土司的特点和承继作了详尽的描述。本文介绍了蒙古尔部族的组成、形成和发展,并对其族长、土司的特点和承继作了详尽的描述。 相似文献
393.
本文对蒙古尔部族的组成、形成和发展作了介绍,其中对族长、土司的特点和承继作了详尽的描述。 相似文献
394.
The present empirical study applies the methodology of information theory to the problem of assessing and separating capital market risk, which is separated into its systematic and unsystematic components. Monthly return relatives for all securities traded on the New York Stock Exchange are examined for the period 1926 to 1971, which is segmented into six 7-year subperiods. The securities are combined into portfolios of various sizes and ranked. It is concluded that although both systematic and unsystematic risks have increased over the 45-year interval—particularly between the pre-1940 and post-1940 periods—they have maintained their relative share of the total risk over the same period. 相似文献
395.
This paper reports the results of three studies conducted to develop, refine, and validate a scale which assessed heterosexual adults' attitudes toward same-sex marriage, the Attitude Toward Same-Sex Marriage Scale (ASSMS). The need for such a scale is evidenced in the increasing importance of same-sex marriage in the political arena of the United States and other nations, as well as the growing body of empirical research examining same-sex marriage and related issues (e.g., Lannutti, 2005; Solomon, Rothblum, & Balsam, 2004). The results demonstrate strong reliability, convergent validity, and predictive validity for the ASSMS and suggest that the ASSMS may be adapted to measure attitudes toward civil unions and other forms of relational recognition for same-sex couples. Gender comparisons using the validated scale showed that in college and non-college samples, women had a significantly more positive attitude toward same-sex marriage than did men. 相似文献
396.
397.
J. Fan R. L. Prentice & L. Hsu 《Journal of the Royal Statistical Society. Series B, Statistical methodology》2000,62(1):181-190
This paper considers a class of summary measures of the dependence between a pair of failure time variables over a finite follow-up region. The class consists of measures that are weighted averages of local dependence measures, and includes the cross-ratio-measure and finite region version of Kendall's τ; recently proposed by the authors. Two new special cases are identified that can avoid the need to estimate the bivariate survivor function and that admit explicit variance estimators. Nonparametric estimators of such dependence measures are proposed and are shown to be consistent and asymptotically normal with variances that can be consistently estimated. Properties of selected estimators are evaluated in a simulation study, and the method is illustrated through an analysis of Australian Twin Study data. 相似文献
398.
John Whitehead Susan Todd & W. J. Hall 《Journal of the Royal Statistical Society. Series B, Statistical methodology》2000,62(4):731-745
In sequential studies, formal interim analyses are usually restricted to a consideration of a single null hypothesis concerning a single parameter of interest. Valid frequentist methods of hypothesis testing and of point and interval estimation for the primary parameter have already been devised for use at the end of such a study. However, the completed data set may warrant a more detailed analysis, involving the estimation of parameters corresponding to effects that were not used to determine when to stop, and yet correlated with those that were. This paper describes methods for setting confidence intervals for secondary parameters in a way which provides the correct coverage probability in repeated frequentist realizations of the sequential design used. The method assumes that information accumulates on the primary and secondary parameters at proportional rates. This requirement will be valid in many potential applications, but only in limited situations in survival analysis. 相似文献
399.
After mindfulness is defined, a brief history of the research on the topic to date is reviewed. This work essentially falls into three categories: health, business, and education. Considerations of mindlessness as a social issue are then addressed. A brief introduction to the articles in this issue follows. These articles speak to mindfulness as it relates to potential solutions to social problems. 相似文献
400.
We consider some of the ways in which mindfulness theory can provide new solutions to current problems and address potential future problems that may result from changes in demographics and technology. Specific research questions are suggested to see how increasing mindfulness and decreasing mindlessnesscan work to diminish these social problems as they occur specifically in the classroom, the workplace, and the social predicament of getting old. We discuss (a) recasting some of the problems of the elderly into problems of perspective about the elderly, (b) mindful ways of dealing with increased ethnic diversity, (c) differentiating between changing the workplace work and changing the character of the work itself and (d) the advantages and ways of increasingmindfulness in the classroom. 相似文献