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81.
The GILDES computer model, incorporating Stumm's concept of proton- and ligand-promoted dissolution, has been used to simulate the exposure of copper at room temperature to 210 ppb sulfur dioxide and 80% relative humidity. The agreement is good between the calculations and laboratory exposures performed under these exposure conditions. Surface reactions are relatively more important at lower relative humidities and the dominant corrosion products formed are solid state Cu2SO3, CuSO3 and Cu2U. Free-radical redox processes are important participants and control the relative distribution of Cu(I)- and Cu(H)-containing corrosion products.  相似文献   
82.
较详细地介绍了在北京核电厂模拟培训中心的模拟器上建立RMS仿真系统的工作。首先对仿真的原型进行分析和简化,建立数学物理模型,并对包括RCS、PZR、SG、CVCS等的近20个核电厂系统进行了动态仿真建模,确定RMS各监测点放射性水平仿真读数的计算方法,最后,给出部分仿真实验结果,以验证数学物理模型的可靠性和适用性。  相似文献   
83.
84.
Memorializes John Bissell (Jack) Carroll, an early leader in the development of psycholinguistics and a dominant contributor to psychometrics and the study of individual differences in cognitive abilities. His seminal work in evaluating foreign language proficiencies across multiple cultures combined his expertise in psycholinguistics with that in psychometrics and defined fundamental issues in the study of language acquisition. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
85.
Seven hundred three members of the Society for Industrial and Organizational Psychology indicated agreement or disagreement with 49 propositions regarding cognitive ability tests in organizations. There was consensus that cognitive ability tests are valid and fair, that they provide good but incomplete measures, that different abilities are necessary for different jobs, and that diversity is valuable. Items dealing with the unique status of cognitive ability were most likely to generate polarized opinions. A 2-factor model, classifying items as those reflecting societal concerns over the consequences of ability testing and those reflecting an emphasis on the unique status of "g," fit the data well, and these factors proved especially important for predicting responses to the more controversial items. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
86.
Changes in maladaptive cognitions may constitute therapeutic processes of multidisciplinary pain programs. A cross-lagged panel design was used to determine whether (a) early-treatment cognitive change predicted late-treatment outcome index change, but not vice versa; and (b) these effects remained significant with depression change controlled. Ninety chronic pain patients, in a 4-week multidisciplinary program, completed measures of catastrophizing, pain helplessness, depression, pain, interference, and activity level at pre-, mid-, and posttreatment. With depression changes controlled, early-treatment catastrophizing and pain helplessness changes predicted late-treatment outcome index changes, but not vice versa; early-treatment depression changes predicted late-treatment activity changes, but not vice versa. Findings advance understanding of pain treatment process and suggest that negative cognition changes may indeed affect improvements in treatment outcome. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
87.
The long-term effects of the Cognitive Adaptation Theory Index (CATI) on psychological and physical health outcomes among men (n=199) and women (n=99) treated for coronary artery disease with percutaneous transluminal coronary angioplasty were examined. The CATI reflects a positive view of the self, a positive view of one's future, and a sense of personal control over daily life. This index was created from questionnaires administered during hospitalization for the initial angioplasty. Four years later, the CATI predicted positive adjustment to disease, even when initial adjustment was taken into consideration. In addition, the CATI predicted a reduced likelihood of sustaining a subsequent cardiac event over 4 yrs. This association was more robust for men. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
88.
In this paper, dynamic model of a class of parallel systems, namely, the hexaslides, is proposed. The model developed is based on the concept the decoupled natural orthogonal complement (DeNOC) matrices, introduced elsewhere. The dynamic model of hexslides, though complex due to the existence of multi-loop kinematic chains, is required for actuator power estimation, computed-torque control, optimum tool trajectory generation, etc. The use of DeNOC offers many physical interpretations, recursive algorithms, and parallel computations. Using the proposed dynamic model, a parallel inverse dynamics algorithm has been presented to compute the actuator forces. This is useful to choose suitable motors for an application. An illustration is provided using an existing machine tool based on hexaslides, namely, the HexaM, while it is carrying out a circular contouring. Secondly, the effect of leg and slider inertias is also studied, which clearly suggests that neither of these can be neglected while finding the actuator forces.  相似文献   
89.
Reviews the book, Computation and Cognition: Toward A Foundation for Cognitive Science by Z. W. Pylyshyn (see record 1986-97211-000). The history of science provides many demonstrations of our intellectual debt to our tools: from Descartes forward, psychological theory has depended on metaphors based on the technology of the day. Computers are the currently exciting technology, and, from that fact alone, one might expect a book with the title Computation and Cognition to invite us to reshape psychological theory in image of the digital computer. That message is not what Pylyshyn has to sell. Instead, he examines computation at a theoretical level and shows that it involves three distinct levels of analysis: a physical, a symbolic, and a semantic level. He argues that to understand mental processes, one needs exactly the same three-level analysis, that is, cognition is computational. In spite of the book's faults, my opinion remains firmly positive: Computation and Cognition is an instant classic. It is a book which deserves to have a major influence on the shape of future work. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
90.
The use of computer models offers a general and flexible framework that can help to deal with some of the complexities and difficulties associated with the development of water management plans as prescribed by the Water Framework Directive. However, despite the advantages modelling presents, the integration of information derived from models into policy is far away from being trivial or the norm. Part of the difficulties of this integration is rooted in the lack of confidence policy makers have on the incorporation of modelling information into policy formulation. In this paper we examine the reasons for this apparent lack of confidence and explore how some tools, presently in use, address this problem. We conclude that public confidence in models is highly dependent on the way uncertainties are addressed and suggest possible directions of action to improve the current situation. Four real case studies illustrate how computer models have been used in The Netherlands for carrying out management plans at regional and national scale. We suggest that the solution to integrate modelling information into policy formulation lies on both the modelling and the policy-making communities.  相似文献   
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