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111.
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van der Velden Peter G.; Kleber Rolf J.; Grievink Linda; Yzermans Joris C. 《Canadian Metallurgical Quarterly》2010,2(2):135
The extent to which the frequency of facing aggression incidents is associated with mental health problems among police officers when organizational stressors, life-events, and previous mental health problems are taken into account is unclear. To elucidate this data from a longitudinal study of police officers was analyzed (N = 473). Mental health problems (MHPs) are here defined as severe anxiety, depression, hostility, burnout symptoms, and/or sleeping problems according the SCL-90–R and MBI. All MHPs were assessed at baseline and 27 months later. Logistic regression showed that serious threat was statistically significant associated with MHPs at follow-up among officers without MHPs at baseline, but not among those with MHPs at baseline. However, stepwise logistic regression showed that serious threat and/or physical aggression were not independently associated with MHPs at follow-up. Organizational stressors, that is, problems with colleagues were independent predictors in all analyses. Among the total study sample, previous MHPs were the strongest independent predictors. These findings suggest superiors should attend to the mental health, organizational stressors and life-events of their officers regularly and not only following critical incidents at work. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
113.
Dawson TL 《Journal of applied measurement》2002,3(2):146-189
In social psychological research the stage metaphor has fallen into disfavor due to concerns about bias, reliability, and validity. To address some of these issues, I employ a multidimensional partial credit analysis comparing moral judgment interviews scored with the Standard Issue Scoring System (SISS) (Colby and Kohlberg, 1987b), evaluative reasoning interviews scored with the Good Life Scoring System (GLSS) (Armon, 1984b), and Good Education interviews scored with the Hierarchical Complexity Scoring System (HCSS) (Commons, Danaher, Miller, and Dawson, 2000). A total of 209 participants between the ages of 5 and 86 were interviewed. The multidimensional model reveals that even though the scoring systems rely upon different criteria and the data were collected using different methods and scored by different teams of raters, the SISS, GLSS, and HCSS all appear to measure the same latent variable. The HCSS exhibits more internal consistency than the SISS and GLSS, and solves some methodological problems introduced by the content dependency of the SISS and GLSS. These results and their implications are elaborated. 相似文献
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Although increases in the use of automation have occurred across society, research has found that human operators often underutilize (disuse) and overly rely on (misuse) automated aids (R. Parasuraman & V. Riley, 1997). Nearly 275 Cameron University students participated in 1 of 3 experiments performed to examine the effects of perceived utility (M. T. Dzindolet, H. P. Beck, L. G. Pierce, & L. A. Dawe, 2001) on automation use in a visual detection task and to compare reliance on automated aids with reliance on humans. Results revealed a bias for human operators to rely on themselves. Although self-report data indicate a bias toward automated aids over human aids, performance data revealed that participants were more likely to disuse automated aids than to disuse human aids. This discrepancy was accounted for by assuming human operators have a "perfect automation" schema. Actual or potential applications of this research include the design of future automateddecision aids and training procedures for operators relying on such aids. 相似文献
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An advanced prototype Computer Controlled Power Wheelchair Navigation System or CCPWNS has been developed to provide autonomy for highly disabled users, whose mix of disabilities makes it difficult or impossible to control their own power chairs in their homes. The working paradigm is “teach and repeat” a mode of control for typical industrial holonomic robots. Ultrasound sensors, which during subsequent autonomous tracking will be used to detect obstacles, also are active during teaching. Based upon post-processed data collected during this teaching event, elaborate trajectories–which may involve multiple direction changes, pivoting and so on, depending upon the requirements of the typically restricted spaces within which the chair must operate–will later be called upon by the disabled rider. An off-line postprocessor assigns an ultrasound profile to the sequence of poses of any taught trajectory. Use of this profile during tracking obviates most of the inherent problems of using ultrasound to avoid obstacles while retaining the ability to near solid objects, such as when passing through a narrow doorway, where required by the environment and trajectory objectives. The work in this article describes a procedure to obtain consistent maps of sonar boundaries during the teaching process, and a preliminary approach to use this information during the tracking phase. The approach is illustrated by results obtained by using the CCPWNS prototype. 相似文献
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Here the authors evaluated the effect of the method of conditioning (bottle or intraoral [IO] infusion) on the strength of a flavor-drug association when measured in a standard 1-bottle consumption test or when measured by IO infusion in a taste reactivity test. When tested with the bottle test in Experiment 1, rats conditioned by bottle displayed stronger taste avoidance than those conditioned by IO infusion. When tested for rejection reactions with the taste reactivity test in Experiment 2, rats conditioned by infusion displayed a stronger aversion than did rats conditioned by bottle. The results suggest that when the contextual cues of conditioning are similar at conditioning and testing, a stronger association is evident regardless of the individual specifics of each method. These results may shed light on recent reports that different neural mechanisms are involved in conditioning by active consumption and passive infusion. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
120.
Hans van Maaren Linda van Norden 《Annals of Mathematics and Artificial Intelligence》2005,44(1-2):157-177
An enhanced concept of sub-optimal reverse Horn fraction of a CNF-formula was introduced in [18]. It was shown that this fraction is very useful in effectively (almost) separating 3-colorable random graphs with fixed node-edge density from the non-3-colorable ones. A correlation between this enhanced sub-optimal reverse Horn fraction and satisfiability of random 3-SAT instances with a fixed density was observed. In this paper, we present experimental evidence that this correlation scales to larger-sized instances and that it extends to solver performances as well, both of complete and incomplete solvers. Furthermore, we give a motivation for various phases in the algorithm aHS, establishing the enhanced sub-optimal reverse Horn fraction, and we present clear evidence for the fact that the observed correlations are stronger than correlations between satisfiability and sub-optimal MAXSAT-fractions established similarly to the enhanced sub-optimal reverse Horn fraction. The latter observation is noteworthy because the correlation between satisfiability and the optimal MAXSAT-fraction is obviously 100%.
AMS subject classification 90C05, 03B99, 68Q01, 68W01 相似文献