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991.
Offshore wind power generation represents a chance to supply energy in a more sustainable way; however, the ecological risks associated with the construction and operation of offshore wind farms are still largely unknown. This paper uses the concept of ecological risk for analysing ecological changes during construction of offshore wind farms. “Ecological risk” is defined as the potentially reduced ability of providing ecosystem services. The ERSEM ecosystem model allows assessing ecological risk based on a number of selected variables (integrity indicators) and under the assumption that increased suspended matter concentration during construction of wind farms affects ecosystem functioning. We conclude that ecological risk is adequate to describe the effects of wind farm constructions, although the computation procedure still needs to be refined and the choice of indicators further optimised. In this context, the choice of indicators available in modelling as well as in monitoring time-series may offer the way forward.  相似文献   
992.
Due to energy crisis and shortage of fossil fuel, there is a growing interest in alternative fuel for internal combustion engine. Producer gas presents a very promising alternative fuel to diesel since it is a renewable and clean burning fuel having properties similar to that of diesel. In this study, a twin cylinder dual fuel diesel engine is experimentally optimized for maximum diesel saving and lower emissions, without any undue vibration of engine using woody biomass producer gas. The test is carried out to study the performance and emission parameters of the engine in diesel mode and dual fuel mode at different gas flow rates under different load conditions. The study reveals that maximum diesel savings is found to be 83% at optimum gas flow rate and 8 kW load. Carbon monoxide, hydrocarbon and carbon dioxide emissions in dual fuel mode were higher compared with diesel mode at all test ranges. However, the main pollutants, such as nitrogen oxide and smoke, decrease substantially in the dual fuel mode compared with the diesel mode. Lower brake thermal efficiency and higher brake-specific energy consumption as well as exhaust gas temperature are observed in dual fuel mode compared with diesel mode.  相似文献   
993.
Sustainable industrial development can be advanced through the development and application of sustainability metrics. This study addressed the application of social sustainability metrics to the measurement of sustainability performance within process industry and to metal production at the plant level in particular. The applied social sustainability indicators are one part of the overall sustainability index which aims at presenting a balanced and holistic view of plant-level sustainability performance. Application of plant-level indicators can support informed decision-making and fill in potential gaps in corporate-level assessments and reporting initiatives with respect to plant-level social sustainability performance. The social part of the overall index provides information on both in-plant sustainability performance and on the direct and in-direct impacts of plant operations on the surrounding society with special emphasis on the supply chain and emerging social due diligence aspects. The results of pilot implementation of social indicators in Ruukki Lappohja plant indicated a very high level of social sustainability performance with minor areas of improvement such as social risk management auditing covering the whole supply chain, suppliers communication on social responsibility requirements to workers and sub-suppliers, signing of the code of conduct by employees and reporting on policies on local community relations, safety in supply chain covering suppliers and contractors and factory health and safety performance in relation to average field of industry performance in this field.  相似文献   
994.
驾驶中使用手机与交通事故之间存在着高度相关性。为揭示使用手机对驾驶行为安全绩效的影响,探索影响驾驶安全的理论机制,采取更有效的干预措施,结合近10 a来相关研究,综述了与驾驶安全密切相关的驾驶分心问题,主要包括:驾驶员分心的定义及其分类;使用手机对驾驶行为安全绩效的影响,如反应时(RT)、行车速度、路线保持和跟车距离;手机使用对驾驶员分心影响的理论机制,如信息加工理论和计划行为理论(TPB)。分析表明,使用手机会导致驾驶员的反应时延长15%~40%,驾驶路线发生明显偏移,对于行车速度减缓和跟车距离延长的假设需结合驾驶员主客观数据进行比较做进一步验证;驾驶过程中使用手机会增加驾驶员的认知负荷,TPB能够对使用手机行为进行有效的解释和预测,但对该理论中基于信念测量的研究还很少;除手机操作任务,影响驾驶员分心的其他操作任务还需做进一步的研究。  相似文献   
995.
为探讨跨国工程项目的安全文化构成及其影响绩效的机制,以巴基斯坦工程项目为调查对象,基于扎根理论提出包含管理层观念文化、作业层观念文化、制度文化、物质文化、安全行为及安全结果等6个结构变量的12个假设。运用AMOS软件,构建并验证了国外项目安全文化影响安全绩效的结构方程模型(SEM)。结果显示,管理层观念文化是影响安全绩效的最重要因素,安全制度文化也是相对重要的因素,而受到宗教文化影响的作业层观念文化则是改善安全绩效的难点。最后提出有利于我国跨国施工企业安全文化建设的建议。  相似文献   
996.
Recognition of acoustic signals when perception is subject to interference from noise has already been extensively studied. In this study the influence of hearing protectors (HP) (plugs, muffs) and hearing loss on signal recognition is examined. Different spectrums and levels of the noise are also included. The test results are shown as the masked threshold for the signals heard and identified. In the case of normally hearing subjects a frequency-independent HP (plug) improves hearing performance, while frequency-dependent HP (muffs) tends to worsen it, especially with low-frequency noise. Hearing losses even worsen hearing performance when plugs are worn. Design suggestions are made to optimise signal recognition. Minimum signal-to-noise ratio and the use of HP are discussed.  相似文献   
997.
Heat stress on workers working outdoors in the power industry may result in fatigue and deterioration in task performance. This research collected and analyzed data on task performance of workers working indoors and outdoors with and without a cooling suit. The task performance was compared on the basis of heart rate, oxygen consumption, tympanic temperature, subjective responses, productivity, and error rates. Based on One-Way Analysis Of Variance (ANOVA) results, a significantly lower estimated working oxygen consumption was observed (p < .001) when the cooling suit was worn. The productivity was higher while workers wore the cooling suit as compared to no cooling suit (p = .011) whereas the error rates were significantly lower(p < .001). Also a significantly lower self-reported discomfort was observed in the neck and shoulders while working wearing the cooling suit (p = .004). This study concluded that wearing a cooling suit while working outdoors was associated with physiological benefits as well as improved task performance of the study participants.  相似文献   
998.
Perceived organizational support (POS) theory specifies three mechanisms—felt obligation, group identification, and outcome expectancy—to explain the effects of organizational support on employee work outcomes. These mechanisms have usually been examined in isolation so that it is not possible to assess their relative explanatory power. The present study aims to remedy this problem by examining the three mechanisms simultaneously using structural equation modeling. On the basis of a sample of 206 bank employees in China, we focus on two types of employee performance—task performance and creativity—as dependent variables. Drawing on self‐determination theory and characteristics of the research context, we propose that task performance is more strongly predicted by felt obligation than by the other two mechanisms, whereas identification and expectancy more strongly predict creativity than felt obligation. We conclude by discussing our contribution to POS and creativity research, and highlight some important implications of our findings. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
999.
This is an introduction to a point/counterpoint exchange in Journal of Organizational Behavior on the negative versus positive sides of organizational citizenship behavior (OCB). Such behaviors go beyond the core tasks that individuals do on the job and are generally considered positive contributions that support organizations. Bolino, Klotz, Turnley, and Harvey cover the dark (negative) side of OCB, arguing that it can be performed for self‐serving motives and that it can have detrimental effects. They discuss the costs of performing OCB to the individuals who perform it, and potential negative consequences for organizations. Conversely, Spitzmuller and Van Dyne cover the light (positive) side, focusing on OCB as forms of either proactive or reactive helping behavior. Proactive helping is motivated by internal needs with the individual seeking out opportunities to engage in OCB. Reactive helping is an altruistic response to a perceived need by a colleague or the organization itself. Taken together, these two papers provide a comprehensive overview of the complex effects of OCB on actors who perform it and targets who receive it. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
1000.
A small but growing body of literature adds to our understanding of the role of team reflexivity (i.e., reflecting upon team functioning) in predicting team performance. Although many studies conclude that reflexivity is an asset for teams, the contingencies of team reflexivity have received far less research attention. In this respect, we argue that team reflexivity may be especially helpful for teams with relatively low performance. Teams that are reflexive tend to learn from previous mistakes, errors, and group processes, which in turn will improve the performance of the team. We propose that this relationship will most likely positively affect learning and final team performance under conditions of relatively poor prior performance. When a team is doing relatively well, the relationship between reflexivity and final team performance will be less clear, as reflexivity and learning is less needed. In a longitudinal study (N = 73 teams), we found support for this idea. As predicted, results indicated that this interaction between team reflexivity and initial team performance on future performance was mediated by team learning. We outline how these findings are important for our understanding of the contingencies of team reflexivity and team performance dynamics. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
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