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861.
862.
863.
A general form for characterizing inverse Gaussian and Wald distributions, based on their respective length-biased distributions, is introduced. Further results for characterizations of the gamma distribution, the negative binomial distribution and some mixtures of them by using their lengthbiased distributions are establised. 相似文献
864.
Lisa R. Larson M.S.W. 《Clinical Social Work Journal》1993,21(2):137-150
Betrayal by a significant object is seen as primary in causing behavioral and emotional disturbances in incest victims, leading to a pervasive identification with the aggressor and disturbances in object relations development. Identification with the aggressor is understood not as a uniform defense mobilized against a specific affect but as a complex compromise formation which defends against anxiety, while also providing libidinal, aggressive and superego gratifications. Far from simply attempting to overcome the past, identifications thus preserve affects that have become pleasurable and self-defining. Two case studies of adolescent girls illustrate how treatment can help victims recognize and begin to forego the sadomasochistic pleasure derived from these identifications, a relinquishment necessary for true mastery. 相似文献
865.
The purpose of this paper is to analyse the role of forestry in the rural economy of Scotland. The Generation of Regional Input-Output Tables (GRIT) technique is applied to the estimation of input-output tables for rural Scotland. This is followed by a forestry-centred multiplier analysis. The results suggest that the forestry planting and harvesting sectors offer great potential for improving economic activity. However, their backward linkages with other rural industries seem to be limited. On the other hand, the backward linkages of wood-processing industries with the rest of the economy are strong. From this analysis, it is concluded that the joint development of forestry and wood-processing industries would promote economic development in rural Scotland. 相似文献
866.
The revised accreditation standards for marriage and family therapy programs (Manual on Accreditation, 1988) require that the curriculum reflect an emphasis on “issues of gender and ethnicity as they relate to marital and family therapy” (p. 13). Training approaches that are described in the professional literature tend to emphasize an understanding of ethnic minorities while deemphasizing the trainee's own ethnic and cultural roots. As such, training lacks dynamic integrity for the white, middle-class trainee. This paper describes a rationale for addressing the ethnic and cultural background of all family therapy trainees and provides training activities to accomplish this end. 相似文献
867.
William S. Pease 《Risk analysis》1992,12(2):253-265
The extent of carcinogen regulation under existing U.S. environmental statutes is assessed by developing measures of the scope and stringency of regulation. While concern about cancer risk has played an important political role in obtaining support for pollution control programs, it has not provided the predominant rationale for most regulatory actions taken to date. Less than 20% of all standards established to limit concentrations of chemicals in various media address carcinogens. Restrictions on chemical use are more frequently based on concerns about noncancer human health or ecological effects. Of the chemicals in commercial use which have been identified as potential human carcinogens on the basis of rodent bioassays, only a small proportion are regulated. There is an inverse relationship between the scope of regulatory coverage and the stringency of regulatory requirements: the largest percentages of identified carcinogens are affected by the least stringent requirements, such as information disclosure. Standards based on de minimis cancer risk levels have been established for only 10% of identified carcinogens and are restricted to one medium: water. Complete bans on use have affected very few chemicals. The general role that carcinogenicity now plays in the regulatory process is not dramatically different from that of other adverse human health effects: if a substance is identified as a hazard, it may eventually be subject to economically achievable and technically feasible restrictions. 相似文献
868.
Peter J. Robinson 《Risk analysis》1992,12(1):139-148
Because of the inherent complexity of biological systems, there is often a choice between a number of apparently equally applicable physiologically based models to describe uptake and metabolism processes in toxicology or risk assessment. These models may fit the particular data sets of interest equally well, but may give quite different parameter estimates or predictions under different (extrapolated) conditions. Such competing models can be discriminated by a number of methods, including potential refutation by means of strategic experiments, and their ability to suitably incorporate all relevant physiological processes. For illustration, three currently used models for steady-state hepatic elimination--the venous equilibration model, the parallel tube model, and the distributed sinusoidal perfusion model--are reviewed and compared with particular reference to their application in the area of risk assessment. The ability of each of the models to describe and incorporate such physiological processes as protein binding, precursor-metabolite relations and hepatic zones of elimination, capillary recruitment, capillary heterogeneity, and intrahepatic shunting is discussed. Differences between the models in hepatic parameter estimation, extrapolation to different conditions, and interspecies scaling are discussed, and criteria for choosing one model over the others are presented. In this case, the distributed model provides the most general framework for describing physiological processes taking place in the liver, and has so far not been experimentally refuted, as have the other two models. These simpler models may, however, provide useful bounds on parameter estimates and on extrapolations and risk assessments. 相似文献
869.
870.
产品设计的符号学解构 总被引:4,自引:0,他引:4
设计具有复杂性,它既不是科学也不是艺术。用符号学的方法来解析设计,产品设计的实质就是以实用功能为核心的文化价值传达,同时也包括审美功能;设计的目的是将造型语言所包含的文化价值如实地传达给消费者;为此,造型设计必须符合其符号学规则,包括语构学规则、语义学规则和语用学规则,规则的复杂性决定设计的复杂性,所以,对这些规则的研究是产品设计体系的基础。 相似文献