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61.
In 3 experiments, novices were required to answer questions while reading a series of problems. The questions required them either to analyze individual problem structures (intraproblem processing) or compare problem structures (analogical comparison processing) to derive answers. Ss who engaged in problem comparison processing were found to categorize and describe problems on the basis of problem structure, whereas those who engaged in intraproblem processing, or simply read the problems, categorized and described them on the basis of surface features. Analogical comparisons also facilitated selection and construction of equations relative to intraproblem processing. These results suggest that analogical comparison is an important component in the induction of problem categories. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
62.
Eight experiments examined facial expressions of surprise in adults. Surprise was induced by disconfirming a previously established schema or expectancy. Self-reports and behavioral measures indicated the presence of surprise in most participants, but surprise expressions were observed only in 4%-25%, and most displays consisted of eyebrow raising only; the full, 3-component display was never seen. Experimental variations of surprise intensity, sociality, and duration/complexity of the surprising event did not change these results. Electromyographic measurement failed to detect notably more brow raisings and, in one study, revealed a decrease of frontalis muscle activity in the majority of the participants. Nonetheless, most participants believed that they had shown a strong surprise expression. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
63.
Addresses the ethical issues associated with establishing a fee structure in private practice based on current trends in Canadian psychology and the existing ethical codes and standards for Canadian psychologists. A number of forces impacting on the delivery and nature of psychological service in Canada are reviewed followed by a critique of relevant codes and standards. Recommendations for establishing a fee structure in private practice are provided based on the critique, alternative ethical codes, and existing literature. It is suggested that when economic necessity forces Canadian psychologists to turn to private practice as their primary source of income, potential conflict between self interest and public interest may arise. Exploration of this conflict raises many unanswered questions regarding the combination of business ethics with the ethics of psychology. To answer these questions and help resolve potential ethical conflicts, further examination and discussion amongst psychologists and their professional associations is recommended. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
64.
65.
We investigated the influences of odor exposure on performance and on breathing measures. The task was composed of tracking, short-term memory, and peripheral reaction parts. During rest or while performing the task, 12 participants were exposed to 4 different odors in 2 intensities. The higher intensity of the malodors induced a short-term decrement in mean inspiration flow (Vi/Ti) after stimulus onset and impaired performance in the short-term memory task, as compared with control trials; no effect was found for the positively judged odors. The study suggests that a distractor as simple as a bad smell may pull a person off task, however briefly, and may result in a detriment to performance. Actual or potential applications of this research involve designing or securing tasks in such a way that a brief withdrawal of attention does not have fatal consequences.  相似文献   
66.
We address a project scheduling problem with resource availability cost for which the activity durations are uncertain. The problem is formulated within the robust optimization framework, where uncertainty is modeled via a set of scenarios. The proposed solution method is based on the scatter search methodology and employs advanced strategies, such as dynamic updating of the reference set, a frequency-based memory mechanism, and path relinking. A multistart heuristic was also developed and comparative results are reported. The tradeoffs for risk-averse decision makers are discussed.  相似文献   
67.
This article presents information on the development and validation of the Facial Expression Coding System (FACES; A. M. Kring & D. Sloan, 1991). Grounded in a dimensional model of emotion, FACES provides information on the valence (positive, negative) of facial expressive behavior. In 5 studies, reliability and validity data from 13 diverse samples, including students, psychiatric patients, and community adults, are presented, and results indicate that raters can reliably agree on instances of positive and negative expressive behavior. Validity studies indicate that FACES ratings are related in predictable ways to another observational coding system, facial muscle activity, individual-difference measures of expressiveness and personality, skin conductance, heart rate, and reports of experienced emotion. FACES can be a useful tool for assessing expressive behavior in a variety of contexts. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
68.
A detailed study of the carrier trapping properties shown by the silicon/oxynitride/oxide gate layers in PowerVDMOS technologies is reported. A quantitative analysis of hole and electron trap densities versus the specific N2O based nitridation process, extracted from Fowler–Nordheim constant current stress kinetics, allows a deep understanding of the role played by those defects in the susceptibility of every nitrided layer.  相似文献   
69.
In this work, the monitoring of the bacterial and chemical dissolution of bornite was evaluated using cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS); the mineral surface was examined using scanning electron microscopy (SEM) and atomic force microscopy (AFM). The analysis of CV results allowed attributing the different peaks observed in both direct and reverse potential scanning to the oxidation of bornite to a secondary covellite and its reduction via different non stoichiometric copper sulphides intermediaries. EIS data for bornite were obtained in control medium up to 78 h of immersion, when a cellular suspension of A. ferrooxidans was added and the experiments continued up to a 192 h of test. The EIS response was different when bacteria were added in the beginning of the test or after some hours of immersion in acid solution. The experiments were performed in different cell configurations and a model of the electrode/electrolyte interface. The correspondent equivalent electrical circuit was used to fit impedance spectra for all studied conditions. A common equivalent circuit used for corrosion processes where anodic (degradation of the mineral) and cathodic (oxygen reduction) reactions occur in parallel, together film and biofilm formation was proposed.  相似文献   
70.
Although survey results seem to indicate an abundant interest among Canadian psychology graduate students in pursuing training in criminal justice psychology, the recruitment and retention of psychologists in the Correctional Service of Canada (CSC) has been of some concern. The present study is a 2008 survey of sites within CSC that provide opportunities for clinical psychology training with offender clientele. Survey findings demonstrated that a broad range of clinical psychology training opportunities were available across 16 sites. The most frequently cited barrier to providing training was lack of time by prospective trainers, and sites reported retaining relatively few of their trainees for subsequent psychologist positions. Information was also obtained regarding vacant psychologist positions across CSC regions. In light of survey findings, substantive discussion is devoted toward the issues of psychologist recruitment and retention in Canadian federal corrections, including a discussion of both potential and existing training initiatives. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
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