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181.
Discusses retouching of the Kallikak family photographs in H. H. Goddard's (1912) study of mental retardation and heredity, with reference to analyses by R. E. Fancher (see record 1987-31600-001) and S. J. Gould (1981), and concurs with Fancher that the retouching was probably not done for deceitful purposes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
182.
The search for good lineal, or depth-first, spanning trees is an important aspect in the implementation of a wide assortment of graph algorithms. We consider the complexity of findingoptimal lineal spanning trees under various notions of optimality. In particular, we show that several natural problems, such as constructing a shortest or a tallest lineal tree, are NP-hard. We also address the issue of polynomial-time, near-optimization strategies for these difficult problems, showing that efficient absolute approximation algorithms cannot exist unlessP = NP.  相似文献   
183.
In his response to my Why There Are No Mental Representations, Robert Cummins accused me of having misinterpreted his views, and attempted to undermine a crucial premise of my argument, which claimed that one could only define a semantic type non-semantically by stipulating which tokens should receive a uniform interpretation. I respond to the charge and defend the premise.  相似文献   
184.
A paradigm of scientific discovery is defined within a first-order logical framework. Within this paradigm, the concept of successful scientific inquiry is formalized and investigated. Among other results, it is shown that a simple method of scientific inquiry is universal in the sense that it leads to success on every problem for which success is in principle possible.  相似文献   
185.
Two experiments, with 80 undergraduates, replicated and extended research by R. T. Croyle and J. Cooper (see record 1984-11595-001) indicating that cognitive dissonance involves physiological arousal. In Exp I, Ss wrote counterattitudinal essays under conditions of high or low choice and, to assess arousal effects owing to effort, with or without a list of arguments provided by the experimenter. In high-choice conditions only and regardless of effort, Ss showed both arousal (heightened galvanic skin response) and attitude change. Arousal, however, did not decline following attitude change. The more effortful task (no arguments provided) produced increased arousal but not greater attitude change. In Exp II, the opportunity to change one's attitude following a freely chosen counterattitudinal essay was manipulated. As in Exp I, arousal increased following the essay but did not decline following a postessay attitude change opportunity. When Ss were not given an attitude change opportunity, however, arousal did decline. It is suggested that if dissonance is a drive state, drive reduction typically may be accomplished through gradual cognitive change or forgetting. (47 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
186.
Summary The throughput of a satellite channel communication is depending upon the link protocol. It is well known that the classical HDLC protocol is inadequate when applied to satellite links instead of short terrestrial links. Several modifications have been proposed to overcome this problem. The present paper gives an analysis and evaluation of a new class of protocols called Virtual Subchannel schemes which splits the satellite link into several components; these subchannels are assigned for transmission in cyclic order and are controlled independently of each other by the classical HDLC procedure.  相似文献   
187.
This paper introduces a generic model for interactive design of constructed facilities. The proposed methodology synthesizes structural problem parameters and conditions in terms of load environment, structural properties, and function of the structure into a hierarchy of possible failure modes. Design evaluations are made in terms of this behavior hierarchy. The user has a high degree of control over the design process and may move at will to any of the design tasks. The model provides a direct link between the system user and the design evaluations during the evaluation/design process.  相似文献   
188.
This paper suggests a general method for compiling OR-parallelism into AND-parallelism. An interpreter for an AND/OR-parallel language written in the AND-parallel subset of the language induces a source-to-source transformation from the full language into the AND-parallel subset. This transformation can be identified and implemented as a special purpose compiler or applied using a general purpose partial evaluator. The method is demonstrated to compile a variant of Concurrent Prolog into an AND-parallel subset of the language called Flat Concurrent Prolog (FCP). It is also shown applicable to the compilation of OR-parallel Prolog to FCP. The transformation identified is simple and efficient. The performance of the method is discussed in the context of programming examples. These compare well with conventionally compiled Prolog programs.  相似文献   
189.
Metallurgical and Materials Transactions A - The use of secondary aluminum for structural components in the automotive industry is limited by the high Fe contents in recycled alloys which often...  相似文献   
190.
Metallurgical and Materials Transactions A - A high $$\gamma ^{\prime }$$ volume fraction CoNi-base superalloy with roughly equal amounts of cobalt and nickel was successfully processed through...  相似文献   
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