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581.
植被覆盖度(FVC)是衡量生态环境优秀的重要指标.本文基于MODIS NDVI数据,运用像元二分法模型,估算了2000~2018年京津风沙源区FVC,分析了其时空变化特征.在此基础上,基于地理探测器模型,定量分析了自然因素和人类活动因素等12个因子对京津风沙源区FVC空间分布的影响.结果表明,近20a来京津风沙源区FVC整体上呈增加趋势,增加率为8.2%.空间上,研究区73.7%的区域FVC在增加,其中显著增加的区域主要集中在晋北山地丘陵亚区、燕山丘陵山地水源保护亚区、大兴安岭南部亚区和科尔沁沙地亚区的南部.2000~2018年,降水是影响京津风沙源区FVC空间分布的主要自然因子,解释力为63.3%;年末大牲畜头数是影响FVC空间分布的主要人为因子,解释力为34.8%.自然因素和人类活动之间的双因子交互作用以双协同作用和非线性协同作用为主,表明相对于单因子,自然因素和人类活动间的交互作用对FVC的解释力更强.其中,降水与其他11个因子的交互作用对研究区FVC起主导作用,解释力超过60%.  相似文献   
582.
Human Performance Modeling (HPM) is a computer-aided job analysis software methodology used to generate predictions of complex humanautomation integration and system flow patterns with the goal of improving operator and system safety. The use of HPM tools has recently been increasing due to reductions in computational cost, augmentations in the tool’s fidelity, and usefulness in the generated output. An examination of an Air Man-machine Integration Design and Analysis System (Air MIDAS) model evaluating complex human-automation integration currently underway at NASA Ames Research Center will highlight the importance to occupational safety of considering both cognitive and physical aspects of performance when researching human error.  相似文献   
583.
Objective. This study aims to quantify the prevalence of work-related musculoskeletal disorders (MSDs) and risks among male kitchen workers in the catering industry. Method. Data were collected with the help of the Nordic musculoskeletal questionnaire and by direct observations. Results. In total, 114 male kitchen workers from various hostels of a college in South India were considered for this study. The average age and mean years of employment of the workers are 26.4 (SD 7.7) and 7.8 respectively. The statistical analysis carried out reveals that 67.5% of male kitchen workers reported MSDs during the past 12 months. The highest prevalence rate has been found in the lower back (65.8%) and shoulder region (62.3%). Among different categories of kitchen work analyzed, it is evident that chief cooks suffer more from MSDs (79.2%) than assistant cooks (74.3%) and kitchen aides (30.0%). Workers in the older group, i.e., ≥41 years, and workers with 6–10 years of experience suffer with higher risk of MSDs, i.e., 93.9% and 87.5%, respectively. Conclusion. The male kitchen workers who participated in this research were found to possess both MSDs and ergonomic hazards.  相似文献   
584.
Objectives. The present study was designed to investigate the simultaneous effects of physical, psychosocial and other work-related risk factors on the work ability index (WAI) score among industrial workers. Methods. This study used a cross-sectional design with a questionnaire survey. A total of 280 workers were included in the study. Data were collected using three questionnaires including the Persian version of the WAI, the Persian version of the job content questionnaire and an author-developed measure (to assess work-related factors, health-related factors and socio-demographic characteristics). Results. The majority of the participants were young, but they had poor WAI scores (mean 37.3?±?6.4) and 44.3% of them had poor or moderate work ability. Occupational accidents and injuries were found to be the strongest predictors of WAI scores. Additionally, there was a strong association between WAI scores and supervisor support, skill discretion, occupational training, sleep quality, work nature and educational level. Conclusions. Intervention programs should focus on improving supervisor support, sleep quality, job skills and knowledge and on decreasing physical and mental work demands. Additionally, implementing a comprehensive occupational health and ergonomics program for controlling and reducing hazardous working environments and occupational injury rates should be considered.  相似文献   
585.
This paper aims to identify specific and generic success factors and barriers in the re-use of electrical and electronic equipment for a variety of different operating models. The scope of the study is information and communication technologies (ICT) and large household appliances. Success factors and barriers for re-use were identified through the conducting of semi-structured interviews with 28 case study partners representing the different models. A list of generic success factors and barriers was identified. From this generic list, the re-use success factors and barriers were ranked by the interviewees with regards to their importance. On the one hand, the difficulty in accessing sufficient volumes of good quality used equipment and the lack of legislations, which support, incentivize and – if necessary – enforce this access, were identified as most impactful barriers. On the other hand, the control and securing of product and process quality were ranked as most important success factors. Re-use organisations, which adhere to good re-use practices, differentiate themselves through quality guarantee from non-compliant, informal competitors. Moreover, proven quality strengthens confidence in re-use of important stakeholders like suppliers, customers, authorities and the general public. Differences in reuse barriers and success factors were also explored for varying geographical regions, product category and operating models.  相似文献   
586.
Green supply chain management (GSCM) integrates ecological concepts with those of supply chain management in order to minimize energy and material usage and to reduce adverse impacts of supply chain activities on the environment. GSCM implementation in mining industries depends largely upon certain factors which are influenced by human behaviours. Human behaviour is dynamic in nature and the relationships between them continuously evolve and change. In this ever-changing context, therefore, identifying and ranking the behavioural factors that affect GSCM implementation becomes essential. This can be taken as a reference by the decision makers while deciding the hierarchy of action necessary for effective implementation of green practices in mining supply chains. The present research attempts to explore various behavioural factors affecting GCSM practices and their interactions which help to attain green-enabled needs. Interpretive structural modelling (ISM) is employed in this research to extract the interrelationships among the identified behavioural factors.  相似文献   
587.
本文针对我国8个典型大气环境试验站的环境因素数据与基础金属腐蚀数据。采用模糊聚类方法对15项环境因素进行分类,探讨各项环境因素之间的相关性。分析结果表明:有4项环境因素对基础金属腐蚀等级的影响性较高。  相似文献   
588.
本研究以巢湖生态清淤为例,在水动力模型的基础上,采用平面二维恒定流和悬浮物扩散数学模型来描述生态清淤施工悬浮物的运动形态和排泥场尾水的影响。结果表明:生态清淤施工悬浮物扩散会给清淤区域内及周边约660 m范围的水体水质造成一定的影响。排泥场尾水排放口下游悬浮物最高浓度约4.8 mg/L,TN浓度最大增量约为0.164 mg/L,TP浓度最大增量约为0.004 mg/L。总体来说,尾水排放的SS、TN、TP对湖区的影响范围不大,其影响程度有限。  相似文献   
589.
饭店绿色竞争力的关键要素与提升路径探讨   总被引:3,自引:0,他引:3  
饭店的绿色竞争力是企业在提高了绿色化水平后在市场竞争中所表现出来的相对优势。绿色竞争力是企业竞争力的一部分,它主要由绿色技术、绿色管理、绿色产品、绿色人力、绿色营销等五个关键要素构成,并通过这些要素的改进和提高来实现饭店整体竞争力的提升。通过绿色竞争力的提高,可以使饭店在不牺牲环境利益的前提下获得更大、更持续的经营效益。  相似文献   
590.
采用UASB+SBR法处理某海洋油田产生的采油废水。针对该废水难降解和高盐度的特性,探讨总盐度、Cl-浓度、处理负荷、曝气时间等因素对生物处理过程的影响,为工程设计及实际应用提供科学依据。  相似文献   
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