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Huang, B. J., Wu, M. S., Hsu, P. C., Chen, J. W., & Chen, K. Y. (2010). Development of high-performance solar LED lighting system. Energy Conversion and Management, 51(8), 1669–1675.
Abstract: The present study developed a high-performance charge/discharge controller for stand-alone solar LED lighting system by incorporating an nMPPO system design, a PWM battery charge control, and a PWM battery discharge control to directly drive the LED. The MPPT controller can then be removed from the stand-alone solar system and the charged capacity of the battery increases 9.7%. For LED driven by PWM current directly from battery, a reliability test for the light decay of LED lamps was performed continuously for 13,200 h. It has shown that the light decay of PWM-driven LED is the same as that of constant-current driven LED. The switching energy loss of the MOSFET in the PWM battery discharge control is less than 1%. Three solar-powered LED lighting systems (18 W, 100 W and 150 W LED) were designed and built. The long-term outdoor field test results have shown that the system performance is satisfactory with the control system developed in the present study. The loss of load probability for the 18 W solar LED system is 14.1% in winter and zero in summer. For the 100 W solar LED system, the loss of load probability is 3.6% in spring.
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Isenstadt, S., Petty, M. M., & Neumann, D. (2015). Cities of Light: Two Centuries of Urban Illumination (). Routledge.
Abstract: Cities of Light is the first global overview of modern urban illumination, a development that allows human wakefulness to colonize the night, doubling the hours available for purposeful and industrious activities. Urban lighting is undergoing a revolution due to recent developments in lighting technology, and increased focus on sustainability and human-scaled environments. Cities of Light is expansive in coverage, spanning two centuries and touching on developments on six continents, without diluting its central focus on architectural and urban lighting. Covering history, geography, theory, and speculation in urban lighting, readers will have numerous points of entry into the book, finding it easy to navigate for a quick reference and or a coherent narrative if read straight through. With chapters written by respected scholars and highly-regarded contemporary practitioners, this book will delight students and practitioners of architectural and urban history, area and cultural studies, and lighting design professionals and the institutional and municipal authorities they serve. At a moment when the entire world is being reshaped by new lighting technologies and new design attitudes, the longer history of urban lighting remains fragmentary. Cities of Light aims to provide a global framework for historical studies of urban lighting and to offer a new perspective on the fast-moving developments of lighting today.
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Johansson, M., Rosen, M., & Kuller, R. (2011). Individual factors influencing the assessment of the outdoor lighting of an urban footpath. Lighting Research and Technology, 43(1), 31–43.
Abstract: During the hours of darkness, the mobility of young women, the elderly and the disabled is limited in urban areas. In a field study possible predictors of the perceived visual accessibility and the perceived danger of an urban footpath were investigated. Eighty-one people individually walked along the footpath after dark. They subjectively assessed the environment and answered a questionnaire about personality and socio-demographics. Visual accessibility was predicted by visual field, environmental trust and brightness. Danger was predicted by the pleasantness of the lighting, gender, brightness and environmental trust. Consequently, the influence of individual characteristics, including the subjective judgments of brightness and hedonic tone and the personality dimension of trust in the physical environment, should be considered in the design of exterior lighting for urban footpaths.
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Jones, B. A. (2018). Spillover health effects of energy efficiency investments: Quasi-experimental evidence from the Los Angeles LED streetlight program. Journal of Environmental Economics and Management, 88, 283–299.
Abstract: Payback estimates of energy efficiency investments often ignore public health externalities. This is problematic in cases where spillover health effects are substantial, such as when the application of new technology alters environmental exposures. When health externalities are included in return on investment calculations, energy efficiency programs may look more or less attractive than suggested by conventional “energy savings only” estimates. This analysis exploits the quasi-experiment provided by the 2009 Los Angeles (LA) LED streetlight efficiency program to investigate the returns on investments inclusive of an originally estimated health externality. Using the synthetic control method, we find that the LED streetlight program is associated with a lagged increase in breast cancer mortality of 0.479 per 100,000. Inclusive of the effects of LEDs on breast cancer and avoided carbon emissions, the LA LED program provides a −146.2% 10-year return compared to +118.2% when health outcomes and carbon emissions are ignored.
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Kostic, A., & Djokic, L. (2014). Subjective impressions under LED and metal halide lighting. Lighting Research and Technology, 46(3), 293–307.
Abstract: In order to compare subjective impressions created by LED and metal halide ambient lighting, a pilot project was conducted in a Belgrade park. All general requirements for an adequate comparison of subjective impressions were fulfilled. The survey was conducted using a questionnaire related to all aspects the researchers considered relevant for subjective evaluation of illuminated pedestrian paths in parks. It was concluded that the respondents, both those who had and those who did not have previous knowledge in the field of lighting, strongly preferred the use of metal halide lamps for the illumination of parks, which is in opposition to the statements of some LED manufacturers. It was also shown that light level and feelings of safety and comfort are evaluated as most important.
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