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951.
Linus Nyiwul 《International Journal of Green Energy》2018,15(4):264-276
Evidence on income as a crucial driver of renewable energy consumption in Africa is mixed. But hydropower accounts for over 90% of renewable energy in sub-Sahara Africa alone. Yet, empirical evidence suggests that hydropower may not be as environmentally sustainable as believed and, as a legacy source of energy in Africa, may not accurately reflect attitudes on renewable energy motivated by environmental concerns. This paper examines the role played by economic performance in the rising sustainable energy consumption in Africa, focusing on the renewable energy sources that are compatible with sustainable development. The difference generalized method of moments, fully modified ordinary least squares, and dynamic ordinary least squares are employed to estimate the statistical significance of income, environmental sustainability proxy, and prices as important drivers of sustainable energy consumption in a panel of 10 African countries for the period 2000–2011—a time frame characterized by a rapid rise in renewables as a priority in environmental policy. With timing and measurement considerations on sources of renewables, results indicate that in contrast to recent literature, the rise in sustainable energy consumption in Africa is strongly driven by rising domestic incomes. In line with literature, however, there is a generally positive, albeit statistically insignificant relationship between sustainable energy consumption and levels of carbon emissions. Oil prices in real terms also correlate with sustainable energy consumption. Available data also show that countries with low energy security also coincidentally tend to have high small hydropower capacity, providing potential for sustainably reducing energy insecurity. 相似文献
952.
Solar energy is one of the major sources of alternative and green energies that humanity need now and will continue to need in the future. There are now a large number of R&D activities on solar power generation facilities and equipment around the world. Located in a subtropical region, Taiwan is rich in solar energy resources; therefore, how to effectively use and store solar energy is a research topic of great interest to Taiwan. The main purpose of this study explores the economic benefits of building-integrated photovoltaics (BIPV) facilities and equipment by analyzing the net present values (NPV) and payback period of the BIPV façade of a shopping mall in Taiwan over its lifecycle. The NPV and payback period analysis results both indicate that the BIPV façade in the case study reaches its breakeven point within 10 years of payback period and 16 years of NPV during a life cycle of 20 years. By showing BIPV investments can bring an acceptable range of benefits profits, this study hopes to provide references for promoting the photovoltaic (PV) industry. 相似文献
953.
《组织行为杂志》2017,38(4):461-486
Younger employees are often promoted into supervisory positions in which they then manage older subordinates. Do companies benefit or suffer when supervisors and subordinates have inverse age differences? In this study, we examine how average age differences between younger supervisors and older subordinates are linked to the emotions that prevail in the workforce, and to company performance. We propose that the average age differences determine how frequently older subordinates and their coworkers experience negative emotions, and that these emotion frequency levels in turn relate to company performance. The indirect relationship between age differences and performance occurs only if subordinates express their feelings toward their supervisor, but the association is neutralized if emotions are suppressed. We find consistent evidence for this theoretical model in a study of 61 companies with multiple respondents. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
954.
This study is to investigate the behavioural responses of zebrafish to the toxic effects of waterborne zinc and chromium(VI). Swimming performance of fish was tracked by a real-time toxicity bio-monitoring system and transformed into data to calculate individual and fish school behavioural endpoints. Behavioural responses under metals were in accordance with the Stepwise Behavioural Response model. Significant and concentration-dependent effects on swimming speed and turning times were found at concentrations equal to or higher than 3.5 mg L-1 for zinc and 0.7 mg L-1 for chromium. Swimming height significantly declined in concentrations equal to or higher than 3.5 mg L-1 under zinc exposure, while for the chromium treatment, it significantly increased in lower concentration exposures and decreased in higher concentration exposures. Average distance and dispersion of fish school decreased at the beginning but there were no obvious changes during the whole exposure period. Behavioural responses under metal exposures were time-dependent: avoidance (increased speed and turning times and decreased average distance and dispersion) might be the first response and followed by height changes. Changes in behavioural endpoints ‘swimming speed and height’ can be used as early stress responses for acute aquatic metal contamination as part of ecological risk assessment. 相似文献
955.
The measurement of environmental impact through composite indexes provides information about the effects of human activities on the ecosystem. Over recent years proposals regarding the environmental composite indexes (ECI) have emerged, suggesting that they can be used to help in decisions about public policies. Due the number of these indicators, issues arise about the asymmetry of information provided, although all ECI seek to measure ecosystem quality or damage. The present paper compares the Composite Index of Environmental Performance (CIEP) (García-Sánchez et al., 2015) and the Environmental Performance Index (EPI) (Hsu et al., 2014) in order to find convergent and divergent characteristics, studying methodological aspects and empirical evidence through statistical analysis, in order to favour the decision-making by stakeholders and to improve the existing ECI in order to determine adequately the environmental impact. The results show that the indexes were developed using different methods and variables, however, they share around 20% identical variables. Despite these differences, the rate of variation in ranking countries between the indexes is 21%, on average. The EPI policy category ‘water & sanitation (effects on humans)’ has two common variables and explains part of the CIEP performance. The effect dimension of the CIEP has one more identical variable and it reduces the individual variation between rank positions. 相似文献
956.
高风险系统组织因素分类与绩效评价 总被引:1,自引:1,他引:0
在收集以组织绩效评价、人的可靠性和人误分析为目的的两类组织因素分类的基础上,结合问卷调查,并依据建立的概念上的组织因素分类框架,从组织的目标和战略、组织结构、资源、规程、管理功能、培训、交流、组织文化等方面确立组织因素分类指标,基本克服了传统的组织因素分类缺陷。同时,依据组织因素的分类,考虑到组织绩效评价的复杂性和不确定性,采用模糊决策方法对某组织的绩效进行评价,识别出该组织现存的主要缺陷:组织管理方面的问题以及组织的结构设计不太合理等问题。 相似文献
957.
958.
Current daylighting standards are not sufficient to guarantee a high-quality daylighting experience as they fail to take the behavior of building occupants into consideration. The way that a daylit room is appreciated and used has not been fully explored, especially under sunlighting conditions. This research is the first of its kind to assess how the distance between a subject and a sun patch on the floor is related to a broad range of behavioral responses, including conclusive preference and measured cognitive performance. One hundred subjects participated in a controlled experiment in a work setting. Investigations of the declared preferences of seating area and subjects' cognitive performances indicated that people are not always aware of the environmental factors that influence their behavior. Subjects were generally attracted to sunlight and outdoor views, but they did not necessarily perform best in these preferred areas. Privacy and a sense of control were two hidden factors that greatly affected subjects' decisions and performances. Current daylighting literature and design practice do not pay adequate attention to such factors as sense of visual control or privacy in the design of rooms. On the other hand, the perceived problem of visual glare caused by sunlight penetration did not affect performance as much as subjects believed it would. An additional result suggested that individual behaviors were more affected by environmental elements than were group activities. 相似文献
959.
蒸散量测定与估算方法的对比研究 总被引:34,自引:1,他引:33
以涡度相关法的实测资料为标准,对波文比-能量平衡法、空气动力学法、Penman-Monteith模型、Shuttleworth-Wallace模型进行对比研究,并分析了各种方法的精度和灵敏度。结果表明:Penman-Monteith模型和波文比-能量平衡法的精度最高,Shuttleworth-Wallace模型和空气动力学法的精度较差。Penman-Monteith模型的稳定性较好,波文比-能量平衡法受Δe和ΔT观测精度的影响大,风温湿观测高度以及下垫面是否均一对空气动力学法影响较大,Shuttleworth-Wallace模型对各类阻抗较为敏感。 相似文献
960.