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| Author | Pun, C.S.J.; So, C.W.; Leung, W.Y.; Wong, C.F. | ||||
| Title | Contributions of artificial lighting sources on light pollution in Hong Kong measured through a night sky brightness monitoring network | Type | Journal Article | ||
| Year | 2014 | Publication | Journal of Quantitative Spectroscopy and Radiative Transfer | Abbreviated Journal | Journal of Quantitative Spectroscopy and Radiative Transfer |
| Volume | 139 | Issue | Pages | 90-108 | |
| Keywords | Light pollution; Night sky brightness; Skyglow; Moon radiation; Urban lighting; Hong Kong | ||||
| Abstract | Light pollution is a form of environmental degradation in which excessive artificial outdoor lighting, such as street lamps, neon signs, and illuminated signboards, affects the natural environment and the ecosystem. Poorly designed outdoor lighting not only wastes energy, money, and valuable Earth resources, but also robs us of our beautiful night sky. Effects of light pollution on the night sky can be evaluated by the skyglow caused by these artificial lighting sources, through measurements of the night sky brightness (NSB). The Hong Kong Night Sky Brightness Monitoring Network (NSN) was established to monitor in detail the conditions of light pollution in Hong Kong. Monitoring stations were set up throughout the city covering a wide range of urban and rural settings to continuously measure the variations of the NSB. Over 4.6 million night sky measurements were collected from 18 distinct locations between May 2010 and March 2013. This huge dataset, over two thousand times larger than our previous survey [1], forms the backbone for studies of the temporal and geographical variations of this environmental parameter and its correlation with various natural and artificial factors. The concepts and methodology of the NSN were presented here, together with an analysis of the overall night sky conditions in Hong Kong. The average NSB in Hong Kong, excluding data affected by the Moon, was 16.8 mag arcsec−2, or 82 times brighter than the dark site standard established by the International Astronomical Union (IAU) [2]. The urban night sky was on average 15 times brighter than that in a rural location, firmly establishing the effects of artificial lighting sources on the night sky. | ||||
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| ISSN | 0022-4073 | ISBN | Medium | ||
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Approved | no | |||
| Call Number | IDA @ john @ | Serial | 186 | ||
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| Author | Kuechly, H.U.; Kyba, C.C.M.; Ruhtz, T.; Lindemann, C.; Wolter, C.; Fischer, J.; Hölker, F. | ||||
| Title | Aerial survey and spatial analysis of sources of light pollution in Berlin, Germany | Type | Journal Article | ||
| Year | 2012 | Publication | Remote Sensing of Environment | Abbreviated Journal | Remote Sensing of Environment |
| Volume | 126 | Issue | Pages | 39-50 | |
| Keywords | Light pollution; Artificial lighting; Urban analysis; Remote sensing; GIS; Darkness; Spatial analysis; Light at night | ||||
| Abstract | Aerial observations of light pollution can fill an important gap between ground based surveys and nighttime satellite data. Terrestrially bound surveys are labor intensive and are generally limited to a small spatial extent, and while existing satellite data cover the whole world, they are limited to coarse resolution. This paper describes the production of a high resolution (1 m) mosaic image of the city of Berlin, Germany at night. The dataset is spatially analyzed to identify the major sources of light pollution in the city based on urban land use data. An area-independent ‘brightness factor’ is introduced that allows direct comparison of the light emission from differently sized land use classes, and the percentage area with values above average brightness is calculated for each class. Using this methodology, lighting associated with streets has been found to be the dominant source of zenith directed light pollution (31.6%), although other land use classes have much higher average brightness. These results are compared with other urban light pollution quantification studies. The minimum resolution required for an analysis of this type is found to be near 10 m. Future applications of high resolution datasets such as this one could include: studies of the efficacy of light pollution mitigation measures, improved light pollution simulations, economic and energy use, the relationship between artificial light and ecological parameters (e.g. circadian rhythm, fitness, mate selection, species distributions, migration barriers and seasonal behavior), or the management of nightscapes. To encourage further scientific inquiry, the mosaic data is freely available at Pangaea: http://dx.doi.org/10.1594/PANGAEA.785492. | ||||
| Address | Freie Universität Berlin, Department of Earth Sciences, Institute for Space Sciences, Carl-Heinrich-Becker-Weg 6‐10, 12165 Berlin, Germany | ||||
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| ISSN | 0034-4257 | ISBN | Medium | ||
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Approved | no | |||
| Call Number | IDA @ john @ | Serial | 188 | ||
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| Author | Femia, N.; Fortunato, M.; Vitelli, M. | ||||
| Title | Light-to-Light: PV-Fed LED Lighting Systems | Type | Journal Article | ||
| Year | 2013 | Publication | IEEE Transactions on Power Electronics | Abbreviated Journal | IEEE Trans. Power Electron. |
| Volume | 28 | Issue | 8 | Pages | 4063-4073 |
| Keywords | light-to-light systems; outdoor lighting; lighting technology; LED; LED lighting; photovoltaics; PV | ||||
| Abstract | This paper discusses the principle of operation, dynamic modeling, and control design for light-to-light (LtL) systems, whose aim is to directly convert the sun irradiation into artificial light. The system discussed in this paper is composed by a photovoltaic (PV) panel, an LED array, a dc-dc converter dedicated to the maximum power point tracking of the PV panel and a dc-dc converter dedicated to drive the LEDs array. A system controller is also included, whose goal is to ensure the matching between the maximum available PV power and the LED power by means of a low-frequency LEDs dimming. An experimental design example is discussed to illustrate the functionalities of the LtL system. | ||||
| Address | Dipt. di Ing. Elettron. e Ing. Inf., Univ. of Salerno, Salerno, Italy | ||||
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| ISSN | 0885-8993 | ISBN | Medium | ||
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Approved | no | |||
| Call Number | IDA @ john @ | Serial | 331 | ||
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| Author | Tähkämö, L.; Ylinen, A.; Puolakka, M.; Halonen, L. | ||||
| Title | Life cycle cost analysis of three renewed street lighting installations in Finland | Type | Journal Article | ||
| Year | 2012 | Publication | The International Journal of Life Cycle Assessment | Abbreviated Journal | Int J Life Cycle Assess |
| Volume | 17 | Issue | 2 | Pages | 154-164 |
| Keywords | LED; LED lighting; Life cycle costs; Light-emitting diode; Payback time; Road lighting; Street lighting | ||||
| Abstract | Purpose Outdoor lighting is facing major changes due to the EU legislation on ecodesign of energy-related products, such as the ban of high-pressure mercury (HPM) lamps widely used in outdoor lighting. This article presents life cycle costs (LCC) of three examples of replacing HPM lamps in street lighting in Finland. The purpose of the article is to assess how the development of light-emitting diode (LED) technology affects LCCs and how the division of LCCs differentiates in the cases. Methods Two of the cases change from HPM lamps to high-pressure sodium (HPS) lamps. In the third one, HPM lamps are replaced by LED luminaires. LED technology predictions of price and luminous efficacy are included in different scenarios. The calculations consider investment and operating costs and residual value. Results and discussion Each replacement reduces the energy costs approximately by half compared to the original HPM lamp luminaires. Energy costs dominate the LCCs of the HPS lamp installations while investment cost is the dominating one in LED luminaire case. The changes from HPM to HPS technology have payback times lower than 9 years, while changing to LED luminaires is not economic. However, the electricity price is low in this case. The payback times of LED installations can be as low as 6 years if the luminaires are installed in 2015 and an average electricity price is used. Conclusions The LCCs of real-life case studies cannot be directly compared, since their luminous properties vary. There is a need for a method for including luminous properties in LCC calculations. |
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| Address | Lighting Unit, School of Electrical Engineering, Aalto University, P.O. Box 13340, 00076, Aalto, Finland | ||||
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| ISSN | 0948-3349 | ISBN | Medium | ||
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Approved | no | |||
| Call Number | IDA @ john @ | Serial | 332 | ||
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| Author | Vitta, P.; Dabasinskas, L.; Tuzikas, A.; Petrulis, A.; Meskauskas, D.; Zukauskas, A. | ||||
| Title | Concept of Intelligent Solid-State Street Lighting Technology | Type | Journal Article | ||
| Year | 2012 | Publication | Electronics and Electrical Engineering | Abbreviated Journal | ElAEE |
| Volume | 18 | Issue | 10 | Pages | |
| Keywords | outdoor lighting; street lighting; LED; LED lighting; energy consumption; algorithm design and analysis; electromagnetic interference | ||||
| Abstract | Street and road lighting consumes about ~2 % of global electric power and the trade-off between energy saving and social needs for traffic safety, crime prevention, aesthetic comfort, etc. has to be established. A wide range investigation of an intelligent solid-state street lighting system prototype equipped with LED-based luminaires, motion sensors and microcontrollers with power-line-communication interfaces was performed under real outdoor conditions. The two-level and two-zone street illumination method was implemented basing on psychophysical investigation. The decrease of efficiency under the dimming conditions and significant electromagnetic interference in the frequency range of tens and hundreds MHz were identified as limiting factors of conventional current regulating ICs and the necessity of further improvement was pointed out. | ||||
| Address | Institute of Applied Research, Vilnius University, Sauletekio av. 9-III, LT-10222 Vilnius, Lithuania | ||||
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| ISSN | 1392-1215 | ISBN | Medium | ||
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| Notes |
Approved | no | |||
| Call Number | IDA @ john @ | Serial | 329 | ||
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