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31.
In attempting to manage their practices efficiently, doctors may not allow seriously ill patients enough time to sort out their feelings and raise important questions. What is at stake here is not information about prognosis and treatments but the very survival of the soul.  相似文献   
32.
Evolution strategies (ESs) are a special class of probabilistic, direct, global optimization methods. They are similar to genetic algorithms but work in continuous spaces and have the additional capability of self-adapting their major strategy parameters. This paper presents the most important features of ESs, namely their self-adaptation, as well as their robustness and potential for parallelization which they share with other evolutionary algorithms.Besides the early (1 + 1)-ES and its underlying theoretical results, the modern ( + )-ES and (, )-ES are presented with special emphasis on the self-adaptation of strategy parameters, a mechanism which enables the algorithm to evolve not only the object variables but also the characteristics of the probability distributions of normally distributed mutations. The self-adaptation property of the algorithm is also illustrated by an experimental example.The robustness of ESs is demonstrated for noisy fitness evaluations and by its application to discrete optimization problems, namely the travelling salesman problem (TSP).Finally, the paper concludes by summarizing existing work and general possibilities regarding the parallelization of evolution strategies and evolutionary algorithms in general.  相似文献   
33.
This paper deals with techniques for obtaining random point samples from spatial databases. We seek random points from a continuous domain (usually 2) which satisfy a spatial predicate that is represented in the database as a collection of polygons. Several applications of spatial sampling (e.g. environmental monitoring, agronomy, forestry, etc) are described. Sampling problems are characterized in terms of two key parameters: coverage (selectivity), and expected stabbing number (overlap). We discuss two fundamental approaches to sampling with spatial predicates, depending on whether we sample first or evaluate the predicate first. The approaches are described in the context of both quadtrees and R-trees, detailing the sample first, acceptance/rejection tree, and partial area tree algorithms. A sequential algorithm, the one-pass spatial reservoir algorithm is also described. The relative performance of the various sampling algorithms is compared and choice of preferred algorithms is suggested. We conclude with a short discussion of possible extensions.  相似文献   
34.
Abstract Many race-specific differences in health outcomes that have been observed in previous research have been attributed to class and racebased group differences which either facilitate or constrain health opportunities and behaviors. These include such variables as different rates of poverty, health insurance coverage, and access to medical care. However, these relationships have been inadequately examined in rural communities where minority status may be even more detrimental to health than in urban areas, due to various constraints on access to health care. We present an analysis that assesses the effects of community, family structure, sociodemographic, and medical care variables on self-reported health status among Hispanics, Mrican Americans, and non-Hispanic whites in six rural communities in Florida. Community structural characteristics had a significant effect on self-reported health, as did some of the measures of how respondents “experience” community. These relationships held even when other sets of variables were added to the models. Family/household characteristics and sociodemographic and medical care variables were less important in explaining self-reported health status. These findings suggest that community continues to be important in explaining differences in health status in rural areas.  相似文献   
35.
As a guide for how to select a new executive director, a family agency adopted the search committee process from higher education. The approach included clarifying agency goals and the director's qualifications, a board-staff screening, and interviews held jointly with public representatives before final board selection.  相似文献   
36.
37.
Increasing attention is being given to the possible consequences which might follow from the exhaustion of the world's natural resources. Countering the pessimistic conclusions of such institutions as the Club of Rome, economists such as Wilfred Beckerman have emphasized the importance of substitution, pointing to many examples where a shortage of one raw material has led to the discovery or development of alternative materials, e.g. artificial for natural rubber, aluminium for copper.Substitution usually occurs through normal market mechanisms, i.e. changes in relative prices. However in some circumstances the market mechanism may be inhibited by a variety of factors, so that its operation requires to be supplemented by an outside agency. This article explores this possibility in relation to the paper making industry, which provides a particularly interesting example owing to the existence of a well established market in waste paper, the main substitute for the major natural resource, woodpulp.A brief indication is given of the relative importance of waste paper and an outline of the structure of the U.K. market; the conditions under which greater utilization of waste paper might occur are then considered taking a sideways look at the influence of the individual. In the final section the various implications for the role of the state are summarized.  相似文献   
38.
Relationships are examined between feelings of political competenceand cumulative media usage in five Western nations. Wide differentiationamong the nations studied is found, suggesting that multivariateanalysis is needed to establish whether media usage makes aunique contribution to feelings of political competence, oracts as a surrogate for other background variables.  相似文献   
39.
This article brings strategy back to managers and their organizations. It argues and demonstrates empirically that what managers do, and the kind of organization they lead, matter in terms of achieving stated objectives. Managerial action involves a set of activities from assessing the problem to prioritising action, and takes place within an organizational context which has two important elements for decision-making. First, organizations have an accumulated stock of experience, and the more managers can access and utilise this experience base the better. Secondly, the culture and structure of an organization may exhibit more or less readiness for the changes that decisions bring about, and contexts less ready for change pose problems for managers in the implementation of decisions.This long-term study of 55 decisions in UK firms shows that careful managerial planning does not of itself guarantee successful outcomes: the organizational context is crucial in framing actions and influencing achievement, and decisions may send a firm on a trajectory beyond the point at which it can plan with confidence. Where experience and readiness are strong, decisions achieve stated objectives—where both are lacking, decisions tend to fail. But, as examination of two illustrative cases indicates, strength in either domain may be enough: sound experience may win out in comparatively unreceptive situations, and decisions may still succeed where experience is lacking but the organization is ready for change. The article closes with some implications for managers.  相似文献   
40.
This article examines the movement of Orthodox Christian refugees from Bosnia to the Habsburg Monarchy in the 1530s and their settlement in a district called ?umberak. The movement of these Uskoks has never been examined in the context of refugee studies. This study of a refugee movement and settlement over a five-century period offers the possibility of reaching a better understanding of the long-term outcome of refugee movements. Ultimately, this article suggests that the refugees affected the land they settled as much as the settlement zone affected them, and that, in this case, the refugees were able to define their own outcome.  相似文献   
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