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van der Ploeg Eleonore; Dorresteijn Sasja M.; Kleber Rolf J. 《Canadian Metallurgical Quarterly》2003,8(2):157
Workers in medium- or high-risk professions are often confronted with critical incidents at the workplace. The impact of these acute stressors may be serious and enduring. Many workers also experience chronic job stressors, such as work overload or role conflicts. This study examined the frequently neglected relationship of acute and chronic stressors with self-reported health symptoms, such as posttraumatic responses, fatigue, and burnout. This association was investigated in a sample of forensic doctors in the Netherlands (N = 84). It was found that the more traumatic events the respondents experienced, the more problems they reported in coping with the traumatic events. Chronic job stressors were associated with posttraumatic responses (intrusions and avoidances) and with burnout and fatigue. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Rinkenauer Gerhard; Osman Allen; Ulrich Rolf; Müller-Gethmann Hiltraut; Mattes Stefan 《Canadian Metallurgical Quarterly》2004,133(2):261
Lateralized readiness potentials (LRPs) were used to determine the stage(s) of reaction time (RT) responsible for speed-accuracy trade-offs (SATs). Speeded decisions based on several types of information were examined in 3 experiments, involving, respectively, a line discrimination task, lexical decisions, and an Erikson flanker task. Three levels of SAT were obtained in each experiment by adjusting response deadlines with an adaptive tracking algorithm. Speed stress affected the duration of RT stages both before and after the start of the LRP in all experiments. The latter effect cannot be explained by guessing strategies, by variations in response force, or as an indirect consequence of the pre-LRP effect. Contrary to most models, it suggests that SAT can occur at a late postdecisional stage. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Pascal Le Gauffre Hatem Haidar David Poinard Katia Laffréchine Rolf Baur Marcello Schiatti 《Computer-Aided Civil and Infrastructure Engineering》2007,22(7):478-488
Abstract: This article provides an overview of a multicriteria decision support methodology for annual rehabilitation programs of water networks. A first set of criteria is formulated for the purpose of comparing and ranking rehabilitation projects. Each proposed criterion is a measure of a particular impact of the condition of a pipe. The ELECTRE TRI method is implemented for defining rehabilitation priorities . Two reference profiles are used to define the limits of three categories associated with three increasing priority levels. With these two reference profiles, applying the ELECTRE TRI method to an asset stock ( a set of pipes that are candidates for rehabilitation ) means assigning each pipe to one of six possible priority groups. A second set of criteria, based on the concept of efficiency, is proposed for comparing alternative rehabilitation programs ( subsets of the asset stock ). 相似文献
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Response time variability is a new optimization problem with a broad range of applications and a distinctive number of theoretic
flavour. The problem occurs whenever events, jobs, clients or products need to be sequenced so as to minimize the variability
of time for which they wait for the next turn in obtaining the resources necessary for their advance. The problem has numerous
real-life applications. We study its computational complexity, present efficiency, polynomial time algorithms for some cases,
and the NP-hardness proof for a general problem. We propose a position exchange heuristic and apply it to improve the total
response time variability of an initial sequence. The latter is the optimum bottleneck sequence, Webster or Jefferson sequence
of the apportionment, or a random sequence. We report on computational experiments with the heuristic. 相似文献
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The paper deals with dynamic buckling of thin-walled structures (plates and beam-columns with open cross-section) subjected to compressive rectangular pulse loading. The local, global and interactive dynamic buckling was analysed. Author proposes the new criterion for critical amplitude of pulse loading leading to stability loss. The proposed criterion is a modification of quasi-bifurcation criterion formulated by Kleiber, Kotula and Saran. Results obtained using proposed criterion were compared with other well-known criteria (Volmir (V) and Budiansky–Hutchinson (B–H) criterion). 相似文献
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Palmitoyl-CoA hydrolase [EC 3.1.2.2.] activity in rat liver was found to be enhanced by high fat diets. Partially hydrogenated
marine oil and high-erucic acid rapeseed oil diets produced a greater increase than a diet containing soybean oil.
With diets containing from 5 to 30% (w/w) of partially hydrogenated marine oil the increase in palmitoyl-CoA hydrolase activity
was similar to the increase observed in peroxisomal β-oxidation activity (correlation coefficient r=0.94). A positive correlation
(r=0.86) also was observed between the activity of palmitoyl-CoA hydrolase and previously determined levels of long-chain
acyl-CoA.
The results presented may suggest a common “induction” mechanism for palmitoyl-CoA hydrolase and peroxisomal β-oxidation enzymes,
possibly exerted through an increased cellular level of long-chain acyl-CoA. 相似文献