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31.
It is becoming increasingly clear that scientists, managers, lawyers, public policymakers, and the public must decide how to value what is provided by, and is a consequence of, natural resources. While “Western” scientists have clear definitions for the goods and services that ecosystems provide, we contend that these categories do not encompass the full totality of the values provided by natural resources. Partly the confusion results from a limited view of natural resources derived from the need to monetize the value of ecosystems and their component parts. Partly it derives from the “Western” way of separating natural resources from cultural resources or values, and partly it derives from the false dichotomy of assuming that ecosystems are natural, and anything constructed by man is not natural. In this article, we explore the previous assumptions, and suggest that because cultural resources often derive from, and indeed require, intact and unspoiled natural ecosystems or settings, that these values are rightly part of natural resources. The distinction is not trivial because of the current emphasis on cleaning up chemically and radiologically contaminated sites, on restoration of damaged ecosystems, on natural resource damage assessments, and on long‐term stewardship goals. All of these processes depend upon defining natural resources appropriately. Several laws, regulations, and protocols depend upon natural resource trustees to protect natural resources on trust lands, which could lead to the circular definition that natural resources are those resources that the trustees feel they are responsible for. Where subsistence or tribal peoples are involved, the definition of natural resources should be broadened to include those ecocultural attributes that are dependent upon, and have incorporated, natural resources. For example, a traditional hunting and fishing ground is less valued by subsistence peoples if it is despoiled by contamination or physical ecosystem degradation; an Indian sacred ground is tarnished if the surrounding natural environment is degraded; a traditional homeland is less valued if the land itself is contaminated. Our argument is that intact natural resources are essential elements of many cultural resources, and this aspect requires and demands adequate consideration (and may therefore require compensation).  相似文献   
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This paper presents a case study of a young woman’s narrative of leaving home and her transition to adulthood. The case study is part of a larger research project about young women with an experience of an early break-up from home, through running away or being thrown out. Empirical material underlying this paper consists of a qualitative study of 12 young women that have been interviewed. The aim of the study is to understand how events like running away/being thrown out of home influences their transition to adulthood. The particular narrative demonstrates how a young woman presents and accounts for such a dramatic event as running away or being thrown out from home, and how that is understood in relation to her adulthood. A further aim is to illustrate how social services efforts are reflected in her narrative.  相似文献   
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Using a 1993 sample (n=107) of persons who teach disability studies courses, a sample (n=27) of disability studies syllabi from the early 1980s, and an extensive bibliography the authors discuss the history and the present condition of disability studies courses in the US and Canada. They discuss the disability paradigm and the methodology used in disability studies courses. The variety and geographical spread of such courses are noted. An extensive comparison of syllabi from the 1980s and the 1990s, including the reading assignments, is carried out.  相似文献   
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The paper provides an empirical analysis of saving and consumption choices of the elderly in Germany, based on the German income and expenditure surveys 1978 and 1983. Main feature of these data is the large sample size making it possible to analyze saving and consumption patterns of the very old (aged 75 and above).The observed age-consumption profiles are very different from those predicted by the pure life-cycle theory. Although wealth is declining between age 60 and 70, it increases again after 70, such that the very old have the highest savings rates among all age groups and accumulate wealth rather than decumulate it. These profiles are not confounded by cohort effects and mortality differences. The corresponding expenditure data suggest the following explanation: due to the generous German pension system and the almost complete coverage of health expenses by the mandatory health insurance in Germany, the declining consumption n very old age cannot exhaust the annuity income of the elderly such that wealth is being accumulated in old age.Research in this paper was supported by the National Institute on Aging, grant no. 3 PO1 AG05842-01. I appreciate the helpful comments by Doug Bernheim, Angus Deaton, Daniel McFadden, Jonathan Skinner, Konrad 'Stahl and David Wise, and two anonymous referees. I am indebted to Hermann Buslei and Johannes Velling who provided most valuable and able assistance.  相似文献   
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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   
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