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61.
Three frames of reference for engineering ethics are discussed—individual, professional and social—which can be further broken down into “microethics” concerned with individuals and the internal relations of the engineering profession and “macroethics” referring to the collective social responsibility of the engineering profession and to societal decisions about technology. Few attempts have been made at integrating microethical and macroethical approaches to engineering ethics. The approach suggested here is to focus on the role of professional engineering societies in linking individual and professional ethics and in linking professional and social ethics. A research program is outlined using ethics support as an example of the former, and the issuance of position statements on product liability as an example of the latter. An earlier version of this paper was presented at the International Symposium on Technology and Society 2000 (ISTAS 2000), Rome, Italy, 7 September 2000. Joseph R. Herkert directs a dual-degree program in engineering and humanities/social sciences and is editor of Social, Ethical, and Policy Implications of Engineering (Wiley/IEEE Press).  相似文献   
62.
In the first part of this article, I raisequestions about Dworkin's theory of theintrinsic value of life and about the adequacyof his proposal to understand abortion in termsof different ways of valuing life. In thesecond part of the article, I consider hisargument in ``The Philosophers' Brief on AssistedSuicide', which claims that the distinctionbetween killing and letting die is morallyirrelevant, the distinction between intendingand foreseeing death can be morally relevantbut is not always so. I argue that thekilling/letting die distinction can be relevantin the context of assisted suicide, but alsoshow when it is not. Then I consider why theintention/foresight distinction can be morallyirrelevant and conclude by presenting analternative argument for physician-assistedsuicide.  相似文献   
63.
The effects of manipulations of response requirement, intertrial interval (ITI), and psychoactive drugs (ethanol, phencyclidine, and d-amphetamine) on lever choice under concurrent fixed-ratio schedules were investigated in rats. Responding on the "certain' lever produced three 45-mg pellets, whereas responding on the "risky" lever produced either 15 pellets (p = .33) or no pellets (p .67). Rats earned all food during the session, which ended after 12 forced trials and 93 choice trials or 90 min, whichever occurred first. When the response requirement was increased from 1 to 16 and the ITI was 20 s, percentage of risky choice was inversely related to fixed-ratio value. When only a single response was required but the ITI was manipulated between 20 and 120 s (with maximum session duration held constant), percentage of risky choice was directly related to length of the ITI. The effects of the drugs were investigated first at an ITI of 20 s, when risky choice was low for most rats, and then at an ITI of 80 s, when risky choice was higher for most rats. Ethanol usually decreased risky choice. Phencyclidine did not usually affect risky choice when the ITI was 20 s but decreased it in half the rats when the ITI was 80 s. For d-amphetamine, the effects appeared to he related to baseline probability of risky choice; that is, low probabilities were increased and high probabilities were decreased. Although increase in risky choice as a function of the ITI is at variance with previous ITI data, it is consistent with foraging data showing that risk aversion decreases as food availability decreases. The pharmacological manipulations showed that drug effects on risky choice may be influenced by the baseline probability of risky choice, just as drug effects can be a function of baseline response rate.  相似文献   
64.
The research reported here focuses on the early acquisition of event structure in German. Based on longitudinal studies from 5 normally developing (ND) and 6 language-impaired (LI) children, a model of "event structural bootstrapping" is presented that spells out how ND children log into the verb lexicon. They project a target-consistent event tree, depicting the head-of-event of transitions. Young LI children, failing to employ this bootstrapping strategy, resort to radically underspecified event representations. The results from a truth-value judgment experiment with 16 ND and 16 LI children showed that ND children perform correctly on transitional verbs, while LI children perform at chance level on the same tasks. These findings are accounted for by the model of event structural bootstrapping to the extent that LI children lack an explicit representation of the head-of-event.  相似文献   
65.
The problem of how to remove information from an agent's stock of beliefs is of paramount concern in the belief change literature. An inquiring agent may remove beliefs for a variety of reasons: a belief may be called into doubt or the agent may simply wish to entertain other possibilities. In the prominent AGM framework for belief change, upon which the work here is based, one of the three central operations, contraction, addresses this concern (the other two deal with the incorporation of new information). Makinson has generalised this work by introducing the notion of a withdrawal operation. Underlying the account proffered by AGM is the idea of rational belief change. A belief change operation should be guided by certain principles or integrity constraints in order to characterise change by a rational agent. One of the most noted principles within the context of AGM is the Principle of Informational Economy. However, adoption of this principle in its purest form has been rejected by AGM leading to a more relaxed interpretation. In this paper, we argue that this weakening of the Principle of Informational Economy suggests that it is only one of a number of principles which should be taken into account. Furthermore, this weakening points toward a Principle of Indifference. This motivates the introduction of a belief removal operation that we call severe withdrawal. We provide rationality postulates for severe withdrawal and explore its relationship with AGM contraction. Moreover, we furnish possible worlds and epistemic entrenchment semantics for severe withdrawals.  相似文献   
66.
The use of a factorial survey to measure the clinical judgments of professionals is described. This design allows the researcher to partial out the effects of variables on clinical decision making while using probability sampling. Methods frequently used to study judgments are reviewed and a study of nurses' judgments about patients' confusional episodes are used to illustrate the application of the factorial survey. Acute confusion in patients is a common clinical problem for nurses working in medical-surgical units in acute care hospitals. Using the factorial survey to study a real-life problem such as confusion demonstrates how this design can be used to test judgments in complex clinical situations, to aid in concept development, and to identify consensus among professionals.  相似文献   
67.
This paper is a case study of what Jon Elster calls "local justice"; particular schemes of justice which, on a relatively autonomous basis, are designed and implemented by institutions and practices to meet particular preferences and goals. The paper suggests an interpretation of the role of justice in sporting games. First, a framework for examinations of schemes of local justice is suggested. Second, norms are suggested that express the requirements that have to be met in order to consider a sporting game as just. The discussion shows that sports are characterized by a particular blend of meritocratic justice in which goods and burdens are distributed according to performance, and a non-meritocratic distribution through which goods and burdens arise as matters of chance. The essay concludes by arguing that the optimal blend of meritocratic justice and chance results in the realization of not merely fair sporting games, but of exciting and good games as well.  相似文献   
68.
张恩迪  崔丽娟 《心理科学》1999,22(5):415-418,453
本研究以问卷调查的方式对上海市中学生,中医药大学生、和普通公众的老虎保护意识进行了对比调查和纵向调查,以评估国际野生生物保护协会亚洲保护交流项目的“拯救虎虎”公众意识宣传教育活动的效果。  相似文献   
69.
A local model of concurrent performance   总被引:5,自引:5,他引:0       下载免费PDF全文
Concurrent procedures may be conceptualized as consisting of two pairs of schedules with only one pair operating at a time. One schedule of each pair arranges reinforcers for staying in the current alternative, and the other schedule arranges reinforcers for switching to the other alternative. These pairs alternate operation as the animal switches between choices. This analysis of the contingencies suggests that variables operating within an alternative produce behavior that conforms to the generalized matching law. Rats were exposed to one pair of stay and switch schedules in each condition, and the probabilities of reinforcement varied across conditions. Both run length and visit duration were power functions of the ratio of the probabilities of reinforcement for staying and switching. The local model, a model of performance on concurrent procedures, was derived from this power function. Performance on concurrent schedules was synthesized from the performances on the separate pairs. Both the generalized matching law and the local model fitted the synthesized concurrent performances. These results are consistent with the view that the contingencies in the alternative, the probability of stay and switch reinforcement, are responsible for performance consistent with the generalized matching law. These results are compatible with momentary maximizing and molar maximizing accounts of concurrent performance. Models of concurrent performance that posit comparisons among the alternatives are not easily applied to these results.  相似文献   
70.
This contribution first searches for historical and empirical evidence for whether and how curricula act or acted as a measure of public education. The problem is explicated on account of a short history of curriculum work and distinguished in a analytical, a political, programmatical and practical discourse of curriculum work. Curriculum work always underlies premises of planning, learning and effects. Three models are finally developed and brought in touch with the different discourses. Curriculum work proves to be an attempt to make publicly acceptable the empirically impossible accountability of schools.  相似文献   
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