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921.
分析知识产权在国家中的地位和作用,指出在经济高度全球化、知识化的今天,知识产权的竞争已成为迄今为止人类社会最高级别的竞争,知识产权的创造水平和保护水平正在成为衡量一个国家综合国力和持续发展力的根本尺度和标志性依据。指出中国企业必须树立强烈的知识产权战略意识,并真正建立起自己的知识产权战略,才能在这场关乎国家和民族的未来、企业的生存与发展的战役中立于不败之地。  相似文献   
922.
This paper presents a tractable set of integer programming models for the days-off scheduling of a mix of full- and part-time employees working α to β days/week (cycle) in a multiple-objective, multiple-location environment. Previous models were formulated to specifically schedule part-time employees working either two or three days per week. These models were intractable because they required complete employee schedule information. The new models are deemed implicit optimal since they are required to supply only essential information. While the number of variables in previous models is an exponential increasing function of β-α, the size of three of the new models is independent of α and β. The first three models developed here (as in [18]) deal with the trade-offs between idle time, the number of employees required to work at multiple “locations,” and the size of the total labor pool. The inherent flexibility of the implicit modeling approach is illustrated by the presentation of various modifications of the basic models. These modifications permit the use of preference weights on the number of employee work days/week (cycle) or the minimization of payroll costs where differential pay rates exist. These latter models may also be formulated such that idle time is ignored, constrained or minimized. The execution time for the implicit models (on a CDC CYBER 730 computer with commercially available software) averaged well under five seconds on 1200 trial problems for the type of application considered in [18]. A solution was obtained in less than 46 seconds of CPU time for a trial problem which would have required over 1.4 million integer variables with previous models. The availability of optimal solutions was invaluable in the development of two heuristics designed to deal with the trade-offs of [16]. In an experimental analysis a previous heuristic produced results which averaged from 74 to 508 percent above optimum across six experimental conditions. The comparable new heuristic produced results which averaged from 3 to 8 percent above optimum for the same experimental conditions. The paper concludes by developing a framework to integrate the results of this research with the tour scheduling problem and by identifying several other areas for related research.  相似文献   
923.
There are numerous variable selection rules in classical discriminant analysis. These rules enable a researcher to distinguish significant variables from nonsignificant ones and thus provide a parsimonious classification model based solely on significant variables. Prominent among such rules are the forward and backward stepwise variable selection criteria employed in statistical software packages such as Statistical Package for the Social Sciences and BMDP Statistical Software. No such criterion currently exists for linear programming (LP) approaches to discriminant analysis. In this paper, a criterion is developed to distinguish significant from nonsignificant variables for use in LP models. This criterion is based on the “jackknife” methodology. Examples are presented to illustrate implementation of the proposed criterion.  相似文献   
924.
Book reviewed in this article: Foreign Aid Reconsidered. By Roger C. Riddell. Overseas Aid: Its Defence and Reform. By Paul Mosley. Missed Opportunities: Britain and the Third World. By Charles Elliott et al.  相似文献   
925.
926.
The UN Convention on the Rights of the Child mandates (Articles 19 and 20) that alternative care be available to protect children from maltreatment by parents and caregivers. Increasingly, countries around the world have recognized the benefits to child well-being of family-based care as an alternative to institutional care. The special if not extraordinary needs of children separated from parents because of abuse, neglect, and maltreatment and placed with foster families requires a commensurate effort to develop foster families who have special if not extraordinary skills. Methods that are effective and replicable across countries offer significant advantages, reducing investments in policies and practices that otherwise would have to be developed independently, country by country. This case study describes the factors that contributed to the transfer of knowledge in the assessment, selection, and training of foster parents and the impact to date.  相似文献   
927.
928.
It is shown that the concept of ?Hawthorne effect‘ was created many years after the Hawthorne studies in Western Electric Company. Presently, the ?Hawthorne effect‘ concept is increasingly used in social sciences and many other sciences. The concept is however used in different and occasionally digressive meanings. The question arises whether such a concept is useful at all. In addition, it is discussed why the rather imprecise reports of single Hawthorne field experiments have been spread as academic folklore, and why rather undefined concepts like the ?Hawthorne effect‘ are used so widely in psychology and social sciences.  相似文献   
929.
We study the pricing policy of a monopolist selling a durable good with the features of a textbook. We assume buyers differ in their valuation of the good and propensity to resell, and identify the possibility of a positive relationship between the quantity of used goods and the price of a new good, and also a higher price for new goods in the last period before a new edition is introduced. Our empirical analysis supports this model: textbook prices increase as the share of used textbooks increases and the end of the current edition approaches. (JEL D420, L120)  相似文献   
930.
Direct experiences, we find, influence environmental risk beliefs more than the indirect experiences derived from outcomes to others. This disparity could have a rational basis. Or it could be based on behavioral proclivities in accord with the well‐established availability heuristic or the vested‐interest heuristic, which we introduce in this article. Using original data from a large, nationally representative sample, this article examines the perception of, and responses to, morbidity risks from tap water. Direct experiences have a stronger and more consistent effect on different measures of risk belief. Direct experiences also boost the precautionary response of drinking bottled water and drinking filtered water, while indirect experiences do not. These results are consistent with the hypothesized neglect of indirect experiences in other risk contexts, such as climate change.  相似文献   
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