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171.
Previous research indicates that the use of impression management is related to supervisor ratings of employee likeability and job performance. It has been argued, though, that employees might also use impression management so that their superiors will see them as ‘good soldiers’ who engage in high levels of organizational citizenship behaviors (OCBs). This study investigates the ways in which three types of impression management—namely, job‐focused, self‐focused, and supervisor‐focused tactics of impression management—influence supervisor ratings of OCB. Using a sample of 122 supervisor‐subordinate dyads, the findings indicate that supervisor‐focused tactics of impression management are positively related to OCB ratings, while job‐focused tactics are negatively related to such evaluations. Additionally, citizenship behaviors are positively related to supervisor liking of the employee and overall ratings of job performance. Finally, the results suggest that OCB ratings mediate the relationship between supervisor‐focused tactics of impression management and supervisor evaluations of employee likeability. Some implications of this study and directions for future research are also addressed. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
172.
The authors investigated whether the relationship between the contents of emotional social support and job burnout among high‐school teachers is spurious because of the role of dispositional positive and negative affectivity. A national sample of 339 teachers was surveyed via a web‐based procedure. Hierarchical regression analyses did not support spuriousness; emotional social support was uniquely predictive of three dimensions of burnout controlling for affectivity. As positive emotional social support increased, emotional exhaustion and cynicism decreased, and professional efficacy increased. As negative emotional social support increased, emotional exhaustion and cynicism also increased. Commonality analyses based on the present data and data reported by K. L. Zellars and P. L. Perrewé (2001; Journal of Applied Psychology, 86, 459–467) provided additional support for the unique role of emotional social support on burnout, but these analyses suggest a greater role of affectivity than emotional social support. These findings have implications for research on burnout as well as the prevention of burnout among teachers. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
173.
This study meta‐analyzed the relationships between locus of control (LOC) and a wide range of work outcomes. We categorized these outcomes according to three theoretical perspectives: LOC and well‐being, LOC and motivation, and LOC and behavioral orientation. Hypotheses reflecting these three perspectives were proposed and tested. It was found that internal locus was positively associated with favorable work outcomes, such as positive task and social experiences, and greater job motivation. Our findings are discussed in relation to research on core self‐evaluation and the Big Five personality traits. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
174.
In recent years, there has been increasing interest in positive organizational scholarship in general, including positive organizational behavior (POB) in particular. This work identifies organizational citizenship behavior (OCB) as a prototypical POB. Conceptualizing OCBs in this way is sensible in light of more than 30 years of research highlighting the desirable aspects of such behavior. At the same time, some researchers have raised questions about positive organizational scholarship and have called for a more balanced view of ostensibly positive behaviors. The purpose of this paper, then, is to take a more nuanced view of OCBs while highlighting the dark side of citizenship behavior. In doing so, we review conceptual and empirical work that has challenged the idea that OCBs are inherently positive. We also discuss research that seeks to develop a deeper understanding of the conditions under which OCB does more harm than good. Finally, important areas for future research and the practical realities facing scholars who seek to publish research investigating the dark side of citizenship are addressed as well. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
175.
A central concern of Intelligent Transportation Systems (ITS) is the effect of in-vehicle devices (e.g., cell phones, navigation systems, radios, etc.) on driver performance and safety. As diverse and innovative technologies are designed and implemented for in-vehicle use, questions regarding the presence and use of these devices assume progressively greater importance. Further concerns for advanced driver training require us to develop and validate reliable and effective procedures for assessing such effects. This work examines a number of candidate procedures, in particular the evaluation of change in cognitive workload as a strategy by which such goals might be achieved.  相似文献   
176.
The aim of the study was to examine the effects of wearing an ice-vest (ca 1 kg) on physiological and subjective responses in fire fighters. The experiments were carried out on a treadmill in a hot-dry environment. The physical cooling effect of the ice-vest was measured with a thermal manikin. The ice-vest effectively reduced skin temperatures under the vest. On average, heart rate was 10 beats/min lower, the amount of sweating was reduced by 13%, and subjective sensations of effort and warmth were lower during work with the ice-vest compared to work without it. Thermal manikin tests indicated that the useful energy available from the vest for body cooling was rather high (58%). In conclusion, the ice-vest reduces physiological and subjective strain responses during heavy work in the heat, and may promote efficient work time by 10%.  相似文献   
177.
This paper presents results of an experimental investigation on the deflagration and deflagration-to-detonation transition (DDT) in an obstructed (blockage ratio BR = 50%), semi-confined flat layer filled with uniform hydrogen–air mixtures. The effect of mixture reactivity depending on flat layer thickness and its width is studied to evaluate the critical conditions for sonic flame propagation and the possibility for detonation onset. The experiments were performed in a transparent, rectangular channel with a length of 2.5 m. The flat layer thickness was varied from 0.06 to 0.24 m and the experiments were performed for different channel widths of 0.3, 0.6 and 0.9 m. The experimental results show flame velocity vs. hydrogen concentration for different thicknesses and widths of the semi-confined flat layer. Three different flame propagation regimes were observed: slow subsonic flame (M << 1), sonic deflagration (M ~ 1) and detonation (M >> 1). It is shown that flame acceleration (FA) to sonic speed is independent of the width of the flat layer. The critical expansion ratio for effective flame acceleration to sonic speed was found to be linearly dependent on the reciprocal layer thickness.  相似文献   
178.
In the Netherlands there are around 400 “Seveso” sites that fall under the Dutch Major Hazards Decree (BRZO) 1999. Between 2006 and 2010 the Dutch Labour Inspectorate's Directorate for Major Hazard Control completed investigations of 118 loss of containment incidents involving hazardous substances from this group. On the basis of investigation reports the incidents were entered in a tailor-made tool called Storybuilder developed for the Dutch Ministry of Social Affairs and Employment for identifying the dominant patterns of technical safety barrier failures, barrier task failures and underlying management causes associated with the resulting loss of control events. The model is a bow-tie structure with six lines of defence, three on either side of the central loss of containment event. In the first line of defence, failures in the safety barriers leading to loss of control events were primarily equipment condition failures, pre start-up and safeguarding failures and process deviations such as pressure and flow failures. These deviations, which should have been recovered while still within the safe envelope of operation, were missed primarily because of inadequate indication signals that the deviations have occurred. Through failures of subsequent lines of defence they are developing into serious incidents. Overall, task failures are principally failures to provide adequate technical safety barriers and failures to operate provided barriers appropriately. Underlying management delivery failures were mainly found in equipment specifications and provisions, procedures and competence. The competence delivery system is especially important for identifying equipment condition, equipment isolation for maintenance, pre-start-up status and process deviations. Human errors associated with operating barriers were identified in fifty per cent of cases, were mostly mistakes and feature primarily in failure to prevent deviations and subsequently recover them. Loss of control associated with loss of containment was primarily due to the containment being bypassed (72% of incidents) and less to material strength failures (28%). Transfer pipework, connections in process plant and relief valves are the most frequent release points and the dominant release material is extremely flammable. It is concluded that the analysis of a large number of incidents in Storybuilder can support the quantification of underlying causes and provide evidence of where the weak points exist in major hazard control in the prevention of major accidents.  相似文献   
179.
To quickly and accurately quantify the material release in process units, gas detectors may be placed according to the results of gas dispersion modeling. DNV's PHAST software is one of the most useful and reliable tools for material dispersion modeling. In this software, fluid dispersion is modeled based on the process conditions, the weather conditions and the specifications of the material release point. However, varying weather conditions throughout the year and the exact determination of the release point on the plot plan and the release elevation are problematic; these issues cause the results to be non-exact and non-integrated. Choosing the most appropriate conditions is challenging. In this paper, a scheme was provided to select the most appropriate conditions for gas dispersion modeling. This scheme approaches modeling based on the worst-case scenario (the situation in which the dispersed gas reaches the detector later in comparison to the other cases). Therefore, different weather conditions, release elevations and release points on the plot plan were modeled for an absorber tower of the Gonbadli Dehydration Unit of the Khangiran Refinery. The worst case of each release condition was then chosen. Finally, gas detectors were placed using the gas dispersion modeling results based on the worst-case scenario.  相似文献   
180.
In this study, an Integrated Simulation-Data Envelopment Analysis (DEA) approach is presented for optimum facility layout of maintenance workshop in a gas transmission unit. The process of repair of incoming parts includes various operations on different facilities. The layout problem in this system involves determining the optimum location of all maintenance shop facilities. Layout optimization plays a crucial role in this type of problems in terms of increasing the efficiency of main production line. Standard types of layouts including U, S, W, Z and straight lines are considered. First, the maintenance workshop is modeled with discrete-event-simulation. Time in system, average waiting time, average machine utilization, average availability of facilities, average queue length of facilities (AL) and average operator utilization are obtained from simulation as key performance indicators (KPIs) of DEA. Also, safety index and number of operators are considered as other KPIs. Finally, a unified non-radial Data Envelopment Analysis (DEA) is presented with respect to the stated KPIs to rank all layouts alternatives and to identify the best configuration. Principle Component Analysis (PCA) is used to validate and verify the results. Previous studies do not consider safety factor in layout design problems. This is the first study that presents an integrated approach for identification of optimum layout in a maintenance workshop of gas transmission unit by incorporating safety and conventional factors.  相似文献   
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