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81.
82.
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
83.
Denise Sato Yamashita Vinícius Amaral Armentano Manuel Laguna 《Journal of Scheduling》2007,10(1):67-76
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
84.
Nolen-Hoeksema Susan; Stice Eric; Wade Emily; Bohon Cara 《Canadian Metallurgical Quarterly》2007,116(1):198
The authors examined the reciprocal relations between rumination and symptoms of depression, bulimia, and substance abuse with longitudinal data from 496 female adolescents. Rumination predicted future increases in bulimic and substance abuse symptoms, as well as onset of major depression, binge eating, and substance abuse. Depressive and bulimic, but not substance abuse, symptoms predicted increases in rumination. Rumination did not predict increases in externalizing symptoms, providing evidence for the specificity of effects of rumination, although externalizing symptoms predicted future increases in rumination. Results suggest rumination may contribute to the etiology of depressive, bulimic, and substance abuse pathology and that the former two disturbances may foster increased rumination. Results imply that it might be beneficial for prevention programs to target this cognitive vulnerability. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
85.
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
86.
Giuseppe Curr Marco Camalleri Denise Calì Francesca Monforte Fortunato Neri 《Microelectronics Reliability》2007,47(4-5):798
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
87.
This paper presents the results of a very recent experimental research program aimed at investigating mixed-mode fracture of reinforced concrete. The tests were designed so that only one single mixed-mode crack generates and propagates through the specimen, as opposed to the usual dense crack pattern found in most of the tests in scientific literature. The specimens were three-point-bend beams of three different sizes. They were notched asymmetrically and reinforced with various ratios of longitudinal and inclined reinforcement. These experiments may help to understand the mechanisms of crack initiation and propagation through reinforcing bars under mixed-mode load conditions. 相似文献
88.
Denise Bevilaqua Heloisa A. Acciari Fabiana A. Arena Assis V. Benedetti Cecílio S. Fugivara Germano Tremiliosi Filho Oswaldo Garcia Júnior 《Minerals Engineering》2009,22(3):254-262
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
89.
Olver Mark E.; Preston Denise L.; Camilleri Joseph A.; Helmus Leslie; Starzomski Andrew 《Canadian Metallurgical Quarterly》2011,52(4):310
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
90.
Denise Fukumi Tsunoda Alex Alves Freitas Heitor Silv��rio Lopes 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2011,15(10):1897-1908
Proteins can be grouped into families according to some features such as hydrophobicity, composition or structure, aiming
to establish common biological functions. This paper presents MAHATMA—memetic algorithm-based highly adapted tool for motif
ascertainment—a system that was conceived to discover features (particular sequences of amino acids, or motifs) that occur
very often in proteins of a given family but rarely occur in proteins of other families. These features can be used for the
classification of unknown proteins, that is, to predict their function by analyzing their primary structure. Experiments were
done with a set of enzymes extracted from the Protein Data Bank. The heuristic method used was based on genetic programming
using operators specially tailored for the target problem. The final performance was measured using sensitivity, specificity
and hit rate. The best results obtained for the enzyme dataset suggest that the proposed evolutionary computation method is
effective in finding predictive features (motifs) for protein classification. 相似文献