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131.
132.
Can Carbon Nanomaterials Improve CZTS Photovoltaic Devices? Evaluation of Performance and Impacts Using Integrated Life‐Cycle Assessment and Decision Analysis
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In emergent photovoltaics, nanoscale materials hold promise for optimizing device characteristics; however, the related impacts remain uncertain, resulting in challenges to decisions on strategic investment in technology innovation. We integrate multi‐criteria decision analysis (MCDA) and life‐cycle assessment (LCA) results (LCA‐MCDA) as a method of incorporating values of a hypothetical federal acquisition manager into the assessment of risks and benefits of emerging photovoltaic materials. Specifically, we compare adoption of copper zinc tin sulfide (CZTS) devices with molybdenum back contacts to alternative devices employing graphite or graphene instead of molybdenum. LCA impact results are interpreted alongside benefits of substitution including cost reductions and performance improvements through application of multi‐attribute utility theory. To assess the role of uncertainty we apply Monte Carlo simulation and sensitivity analysis. We find that graphene or graphite back contacts outperform molybdenum under most scenarios and assumptions. The use of decision analysis clarifies potential advantages of adopting graphite as a back contact while emphasizing the importance of mitigating conventional impacts of graphene production processes if graphene is used in emerging CZTS devices. Our research further demonstrates that a combination of LCA and MCDA increases the usability of LCA in assessing product sustainability. In particular, this approach identifies the most influential assumptions and data gaps in the analysis and the areas in which either engineering controls or further data collection may be necessary. 相似文献
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“Cruising” infants can only walk using external support to augment their balance. We examined cruisers' understanding of support for upright locomotion under four conditions: cruising over a wooden handrail at chest height, a large gap in the handrail, a wobbly unstable handrail, and an ill‐positioned low handrail. Infants distinguished among the support properties of the handrails with differential attempts to cruise and handrail‐specific forms of haptic exploration and gait modifications. They consistently attempted the wood handrail, rarely attempted the gap, and occasionally attempted the low and wobbly handrails. On the wood and gap handrails, attempt rates matched the probability of cruising successfully, but on the low and wobbly handrails, attempt rates under‐ and overestimated the probability of success, respectively. Haptic exploration was most frequent and varied on the wobbly handrail, and gait modifications—including previously undocumented “knee cruising”—were most frequent and effective on the low handrail. Results are discussed in terms of developmental changes in the meaning of support. 相似文献
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Donna Fisher‐Thompson 《Infancy》2014,19(3):227-261
This study examined how look dynamics contribute to infants’ emerging novelty preferences. Time‐series analyses were used to study the temporal nature of looking displayed by 3‐ to 5‐month‐old infants during a serial paired‐comparison task. Evidence was found only for short‐term stability: Novelty preferences and side biases were not stable from one visit to the next, but looking was consistent from one moment to the next producing stability within trials and temporarily across trials leading to the formation of behavioral runs. Persistence in looking left or right across multiple trials did not change from one visit to the next, but persistence in looking at familiar stimuli declined with age. By Visit 3, familiarity runs occurred less often than did novelty runs. Frequent but highly variable runs, including surprisingly late familiarity preferences, suggest that overall side biases and novelty preferences found during visual preference tasks are emergent phenomena affected by moment‐to‐moment changes in looking. 相似文献
138.
Ideologies & Narratives in Relation to ‘Fat’ Children as Bullies, ‘Easy Targets’ and Victims
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In this study, we explore narratives in relation to ‘fatness’, drawing on focus group interviews with parents, early years practitioners, teachers and young people. The study is located in a larger study on bullying and resilience, with no specific focus on obesity or ‘fatness’. Analysis of the interview data highlighted a recurrent focus on ‘fatness’ within the participants’ narratives, by labelling and stigmatising the ‘fat kid’ and ‘bigger children’. We conclude that obesity and fatness, as abnormalities, are now included in commonsense talk in relation to ‘easy targets’, victims and bullies. 相似文献
139.
Hannah Schürenberg‐Frosch 《Development policy review : the journal of the Overseas Development Institute》2014,32(3):327-353
Given the scarce resources for public investment in developing countries, policy analysis should include a detailed perspective on the effects of infrastructure. This article develops a modelling framework for analysing the effects of improved road infrastructure on the economy of African countries. The theoretical framework is tested empirically and used for simulations in a Computable General Equilibrium (CGE) model, and the effects on production and welfare are analysed. The model also serves to investigate the effect of roads on the economic participation of rural households. 相似文献
140.
The current economic climate demands more innovative approaches to increasing labor market participation for people with disabilities. Social entrepreneurship (SE) offers one alternative employment pathway. However, little is known about the broader factors influencing SE for people with disabilities. Using empirical data from focus groups comprised of social entrepreneurs with disabilities and interviews with key stakeholders working in the fields of policy, disability, and business, this research frames its analysis in the intersection of disability studies and entrepreneurship to explore which factors influence the potential for SE to provide equal participation opportunities for people with disabilities in the labor market. Findings suggest that further consideration of political–economic and socio-cultural factors is needed if we are to better understand the potential of SE for people with disabilities. 相似文献