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It is well recognized that performance changes over time. However, the effect of these changes on overall assessments of performance is largely unknown. In a laboratory experiment, we examined the influence of salient Gestalt characteristics of a dynamic performance profile on supervisory ratings. We manipulated performance trend (flat, linear-improving, linear-deteriorating, U-shaped, and ∩-shaped), performance variation (small, large), and performance mean (negative, zero, positive) within subjects and display format (graphic, tabular) between subjects. Participants received and evaluated information about the weekly performance of different employees over a simulated 26-week period. Results showed strong main effects on performance ratings of both performance mean and performance trend, as well as interactions with display format. Theoretical and practical implications of the results are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Awareness of the construction environment can be improved by automatic three-dimensional (3D) sensing and modeling of job sites in real time. Commercially available 3D modeling approaches based on range scanning techniques are capable of modeling static objects only, and thus cannot model dynamic objects in real time in an environment comprised of moving humans, equipment, and materials. Emerging prototype video range cameras offer an alternative by facilitating affordable, wide field of view, dynamic object tracking at frame rates better than 1?Hz (real time). This paper describes a methodology to model, detect, and track the position of static and moving objects in real time, based on data obtained from video range cameras. Experiments with this technology have produced results that indicate that video rate 3D data acquisition and analysis of construction environments can support effective modeling, detection, and tracking of project resources. This approach to job site awareness has inherent value and broad application. In combination with effective management practices and other sensing techniques, this technology has the potential to significantly improve safety on construction job sites. 相似文献
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Hahlweg Kurt; Markman Howard J.; Thurmaier Franz; Engl Jochen; Eckert Volker 《Canadian Metallurgical Quarterly》1998,12(4):543
This article reports on the development and long-term evaluation of a marital distress prevention program for German couples, the Ein Partnerschaftliches Lernprogramm (EPL, A Couple's Learning Program). The EPL is a 6-session program designed to teach couples effective communication and problem-solving skills. In the current article, the EPL is evaluated in a prospective, quasi-experimental, controlled trial. The results of the 3-year follow-up are reported, contrasting 55 EPL couples with a control group of 17 couples. Significant differences emerged with regard to the couples' dissolution rates, relationship satisfaction, and positive and negative communication behavior favoring the EPL couples. These results demonstrate the utility of the EPL program in assisting happy couples who are preparing for marriage. The implications of the findings for prevention research and for the dissemination of prevention programs are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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The aim of this study was to contrast the validity of two opposing explanatory hypotheses about the effect of online communication on adolescents' well-being. The displacement hypothesis predicts that online communication reduces adolescents' well-being because it displaces time spent with existing friends, thereby reducing the quality of these friendships. In contrast, the stimulation hypothesis states that online communication stimulates well-being via its positive effect on time spent with existing friends and the quality of these friendships. We conducted an online survey among 1,210 Dutch teenagers between 10 and 17 years of age. Using mediation analyses, we found support for the stimulation hypothesis but not for the displacement hypothesis. We also found a moderating effect of type of online communication on adolescents' well-being: Instant messaging, which was mostly used to communicate with existing friends, positively predicted well-being via the mediating variables (a) time spent with existing friends and (b) the quality of these friendships. Chat in a public chatroom, which was relatively often used to talk with strangers, had no effect on adolescents' well-being via the mediating variables. 相似文献
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An 84-year-old male presented to the emergency room with the chief complaint of painful, swollen penis following the use of a constriction ring to maintain penile erection. A high fever, chills and hypotension were recognized. Septic shock was presumed, and administration of antibiotics was started. Microbiologic cultures revealed Escherichia coli in blood. We herein report a rare but serious complication accompanying incarceration of the penis. 相似文献
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Jochen Schütz 《Journal of scientific computing》2014,60(2):438-456
We apply the concept of asymptotic preserving schemes (SIAM J Sci Comput 21:441–454, 1999) to the linearized \(p\) -system and discretize the resulting elliptic equation using standard continuous Finite Elements instead of Finite Differences. The fully discrete method is analyzed with respect to consistency, and we compare it numerically with more traditional methods such as Implicit Euler’s method. 相似文献
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