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941.
中国煤电行业的发展伴随着各种环境风险,本文以典型煤电企业为例,在产能过剩、能效标准提高、环境保护税、全国碳市场、水资源税和非水可再生能源规划目标的风险约束下,建立环境成本内部化和环境风险分析工具,考虑不同压力情境下对煤电企业价值的影响,构建环境风险影响财务成本的压力测试框架。结果表明,对单个风险而言,产能过剩和碳市场风险对企业价值的影响是大多数地区在不同情景中面临的主要风险驱动因素。对于综合风险压力测试而言,各地区1 000MW超超临界机组乐观情景及悲观情景的企业价值距合理回报预期企业价值相差小,而300MW和600MW亚临界机组因能效水平低、经营成本高等原因在环境风险压力下企业价值偏离合理回报较多。随着环境风险严重程度的不断增加,环境压力测试有助于煤电企业和金融机构了解环境风险对企业财务状况的影响,从而对投资决策产生影响。  相似文献   
942.
Most research on workplace aggression focuses on the antecedents and consequences of aggression for individual workers. The current study examines how shared workplace aggression concerns relate to internal and external organizational outcomes. Drawing on the work stress, social identity, and social contagion literatures, we propose relationships between unit‐level aggression concerns and unit‐level measures of performance and employee attitudes in a public school sample (2989 employees; 163 schools). We also propose that these relationships differ depending on the resource context of the school. Consistent with our expectations, schools in which teachers had strong shared concerns about aggression also had poorer shared job attitudes and poorer student outcomes, as indicated by average standardized test scores at the school. The impact of shared concerns about aggression on school‐level standardized test scores was stronger for resource‐rich schools than for schools with fewer resources. The current study contributes to organizational research as it establishes that workplace aggression concerns have adverse consequences for the whole organization, not only for the individuals experiencing the events. Our findings demonstrate that employees' shared concerns about aggression have an impact on organizational outcomes and suggest a prevention‐focused approach to workplace aggression. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
943.
We theorized that organization–environment adaptation, the interaction between external demands and personnel resources, predicts distress and morale. We tested this hypothesis in 29 stations within one state police department, and combined three data sources. We measured environmental demands for policing via census data pertaining to the station precinct (e.g., per cent unemployed; per cent in public housing). We assessed resources via personnel numbers within stations. Outcomes were employee's perceptions of staff distress and morale at the station (N = 247), assessed twice, 14 months apart. Using hierarchical linear modeling, we found that environmental demands predicted perceptions of workgroup distress and morale and that the relationships were moderated by personnel resources. For distress, when resources were low, demands were positively associated with distress; when resources were high, demands were negatively associated with distress. For morale, when resources were high, demands were positively associated with morale; there was no relationship when resources were low. Results show that aversive and pleasurable reactions at work may be traced to how resources are employed to manage external demands. Results support a macro‐level shift in modeling distress and morale, incorporating external demands, and strategic management decisions regarding personnel resourcing. Our research suggests that rather than being a result of individual failure to adapt, compromised work ability may result from an organizational failure to adapt to the environmental context. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
944.
Nurses are often obliged to work in a 12-hr shift work system. We have decided to check whether such a working system constitutes an excessive load for nurses. On the basis of a questionnaire survey among nurses working in an 8-hr daytime shift system (169 nurses) and in a 12-hr shift (536 nurses), the amount of physical workload, work stress, and after-work activities were compared. Data analysis has shown that a 12-hr shift system is characterized by less significant physical workload but greater mental load. The nurses working in a 2-shift system were more tired after work, but they could spend more time on leisure activities and do housework. The data suggest that there are no significant contraindications for nurses to work in a 2-shift system.  相似文献   
945.
Abstract

Sixty female prawn seed collectors and 60 female control subjects from Sajenakhali and Sandeshkhali blocks of Sunderbans, West Bengal, India, were randomly selected to evaluate and compare musculoskeletal disorders and physiological stress. The control group was engaged in domestic work involving minimum hand-intensive activities. The modified Nordic musculoskeletal questionnaire and rapid entire body assessment were used. Most subjects suffered from discomfort in different body parts, especially in the lower back (98%), knees (88%), shoulders (75%), ankles (70%) and feet (67%). This study reveals that female prawn seed collectors suffer from significant physiological load and extreme physiological stress due to prolonged working hours in a standing posture and excessive work pressure. Consequently, all these factors affect female prawn seed collectors ‘ health and work performance.  相似文献   
946.
947.
呼吸防护用品符合人的形态与生理特征,才能保证其防护效果和舒适性。笔者从人体的面部形态与生理机能角度,分析了呼吸防护用品与人体的适配性,系统提出密合性、呼吸阻力、死腔、视野等呼吸防护用品的人机工效学问题。该论文取得的成果,对进一步丰富呼吸防护用品人机工效学研究内容,指导呼吸防护用品的设计与生产,提升我国呼吸防护用品的防护效果与核心竞争力,以期发挥积极的推动作用。  相似文献   
948.
高温环境对煤矿井下作业人员影响的调查研究   总被引:3,自引:0,他引:3  
本文就高温高湿环境对煤矿工人的生理心理危害程度进行调查研究。结果显示,在非高温矿井中,粉尘和噪声的影响居于首位,而在高温矿井中,高温成为影响煤矿井下工人生理和心理的首要因素。疲劳主观症状问询结果显示,高温矿井工人在身体症状、精神症状和感觉症状方面的反应都明显高于非高温矿井工人,尤以采煤工种更为突出。调查结果提示,煤矿井下高温高湿对工人的生理心理影响是相当严重的,企业应采取有效措施防治高温危害,保护广大煤矿工人的身心健康。  相似文献   
949.
胡小弟 《环境技术》2005,23(1):8-12
综合环境应力可靠性试验系统是实施电子设备可靠性试验的重要技术手段,根据试验对象的试验技术要求编制试验设备系统配置及主要技术指标是关系试验设备能否完成试验任务的关键。正确合理地编制系统配置和技术指标无论于技术角度和经济角度都有着十分重要的意义。正确的配置设计和指标论证依托于对试验设备构成技术的深入研究和相关关系的准确把握。综合环境应力可靠性试验系统的配置设计和技术指标论证方法,对其他环境试验设备的选型论证也有一定的指导意义。  相似文献   
950.
Dynamic mechanical properties including temperature effect, stress softening, and Payne effect are studied on the elastomer composites filled with soy protein or carbon black. The comparison of protein composite with well-known carbon black composites provides further insight into the protein composites. The elastomers filled with soy protein aggregates give substantial reinforcement effect when compared with the unfilled elastomers. Approximately 400 times increase in shear elastic modulus was observed when 40% by weight of protein is incorporated into the elastomers. The sample films were cast from the particle dispersion of soy protein isolate and carboxylated styrene–butadiene latex. At the higher temperatures, the shear elastic modulus of soy protein-filled composites does not decrease as much as that of the carbon black-filled composites. The behavior of elastic and loss modulus under the oscillatory strain of different magnitude is similar to that of carbon black reinforced styrene–butadiene rubber. However, carbon black composites show a better recovery behavior after eight cycles of dynamic strain. The reduction of shear elastic modulus with dynamic strain (Payne effect) was compared with Kraus model and the fitting parameter related to the aggregate structure of the soy protein. A reasonable agreement between the theoretical model and experiment was obtained, indicating the Payne effect of the protein-related network structure in the elastomers could also be described by the kinetic agglomeration de-agglomeration mechanism.  相似文献   
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