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[en] The mains characteristics of LED output lighting are high efficiency, long lifetime and the ability of low level voltage operation, making it suitable for working with photovoltaic panels. In the beginning this application was constrained to isolated and disaster areas where there are not possibilities of connection with the electric grid, this situation is changing as a consequence of the systematic price reduction in photovoltaic panels and LEDs and the increasing of the efficiency of this light source, therefore this option has become attractive in lighting projects of new facilities. It is important to know that in our country we have the means for the design and manufacturing of the elements of the lighting system and for making the lighting project, assuring a high level of national production integration. In this work the factors that make possible the feasibility of this type of illumination are analyzed and several options for its implementation are proposed. (author)
[en] Energy security at the household level implies ensuring assured and regular supply of clean energy fuels at an affordable price for various household activities. Threat to physical availability of clean energy fuels for cooking and lighting is determined through various indicators such as dependence on traditional fuels and limited access to clean fuels. Energy insecurity translates into various adverse social impacts. Financial threat to energy security is indicated by expenses incurred on energy fuels and affordability of clean fuels. Households spend a major portion of their income on acquiring energy fuels; however, due to high price of clean fuels, they continue to depend on traditional and inefficient fuels. There is an urgent need to address factors that pose a threat to energy security at the household level. In this regard, measures taken by the government agencies and other institutions are also reviewed. The paper also suggests the regulatory and policy interventions required to address the energy security issues at the household level. (author)
[en] Highlights: • Proper design of efficient lighting systems. • The reliability and durability of the light sources. • Maintenance of lighting systems. • Quality standards of LED lamps. • Optimum economic choice of light sources. - Abstract: The performance of lighting system must be calculated in order to determine the energy requirements of the building. In the normative [EN 12464-1] are established lighting requirements which have effects on energy needs. The European standard [EN 15193] provides guidance on that evaluation. The easiest way to comply with reduction of energy requirements leads to the replacement of traditional lamps with LED ones, but if we calculate also the reliability parameters, the economic return is not guaranteed. Using bibliographic data, we have compared lighting’s results for a museum (LED lamps versus CFL and halogen lamps). The objective function of the study is to optimize the energy consumption of lighting systems, but at the same time to assess the reliability (MTTF of the lamps) of these systems. Without accurate information about this last parameters, the right choice of the lamps cannot be done successfully
[en] Light emitting diode (LED) sources have been widely used for illumination. Optical design, especially freedom compact lens design is necessary to make LED sources applied in lighting industry, such as large-range interior lighting and small-range condensed lighting. For different lighting requirements, the size of target planes should be variable. In our paper we provide a method to design freedom lens according to the energy conservation law and Snell law through establishing energy mapping between the luminous flux emitted by a Lambertian LED source and a certain area of the target plane. The algorithm of our design can easily change the radius of each circular target plane, which makes the size of the target plane adjustable. Ray-tracing software Tracepro is used to validate the illuminance maps and polar-distribution maps. We design lenses for different sizes of target planes to meet specific lighting requirements. (condensed matter: electronic structure, electrical, magnetic, and optical properties)
[en] Highlights: • Radiance can be recalculated to more common local luminance and luminous intensity. • Communal trends in reduction or increase of light pollution can be analyzed remotely. • No correlation between crime and luminous intensity of communities. • No other than normal distribution of accidents at low light levels found. • Crayfish seem to survive only in habitats lit less than 4.5 times full moon. - Abstract: We present a novel transparent method to analyze measurements of the Suomi NPP (Suomi National Polar-orbiting Partnership) satellite in night vision, into luminous intensity and luminance on the community level, with a special focus to address light planners and non-experts, and for the first time, to further address politicians, decision-makers and law-makers, and governmental agencies. We checked the propagated efficiency of road lighting and its impact on luminous flux, and identified a waste of light emissions in the largest city of Switzerland, Zurich. We looked at security (issues like criminal acts) and found no correlation with communities’ luminous intensity. We assessed road safety (accidents) against local luminance and found no evidence of darkness being more risky when the overall distribution of illuminance on roads is considered. We screened crayfish habitats in the Canton of Zurich against local illuminance and found clear evidence of preferred darkness for the living. Based on this finding, we propose an upper limit for light immissions in the crayfish habitats. These four analyses have been chosen to demonstrate the usefulness of Suomi NPP's coverage in combination with our approach. We could apply it to ecological, social and economical topics. We hope others will follow and we can draw more attention of governments to take action to reduce the light pollution on local levels, like Langnau am Albis of Switzerland has exemplified.
[en] About 78 million rural households in India reportedly lack access to grid electricity. About 67 million of them use kerosene for lighting. Government of India is promoting the use of solar home systems (SHS) as one of the options for meeting lighting requirements in households in remote and less inhabited villages. About 363,399 SHS were reportedly disseminated across the country by December 2007. Apart from meeting the basic lighting need of the households, SHS also help in abating the emissions of green house gases (GHGs) by directly displacing the use of kerosene in households that currently use it for lighting. This study has attempted at estimating the CO2 mitigation potential of SHS in India by studying the potential for their diffusion and the appropriate baseline. Subsequently, the scope for cost reduction to the user due to carbon finance, if received, is also studied. It is found that carbon finance could reduce the effective burden of SHS to the user by 19% if carbon prices were $10/tCO2 and no transaction costs were involved in getting the carbon revenues. These benefits are also estimated for scenarios where transaction costs are incurred by the project proponent in getting the carbon benefits
[en] Highlights: • We discussed the image preprocessing, object detection and pose estimation algorithms under poor light condition of inner vessel of EAST tokamak. • The main pipeline, including contours detection, contours filter, MER extracted, object location and pose estimation, was carried out in detail. • The technical issues encountered during the research were discussed. - Abstract: Experimental Advanced Superconducting Tokamak (EAST) is the first full superconducting tokamak device which was constructed at Institute of Plasma Physics Chinese Academy of Sciences (ASIPP). The EAST Articulated Maintenance Arm (EAMA) robot provides the means of the in-vessel maintenance such as inspection and picking up the fragments of first wall. This paper presents a method to identify and locate the fragments semi-automatically by using the computer vision. The use of computer vision in identification and location faces some difficult challenges such as shadows, poor contrast, low illumination level, less texture and so on. The method developed in this paper enables credible identification of objects with shadows through invariant image and edge detection. The proposed algorithms are validated through our ASIPP robotics and computer vision platform (ARVP). The results show that the method can provide a 3D pose with reference to robot base so that objects with different shapes and size can be picked up successfully.
[en] The outdoor lighting in the nuclear power plant don't automatically shut down,and cause lights to be long-light. It is proposed to install light-control switches in the electric circuit in order to achieve automatic control. The original outdoor lighting circuit uses the circuit breaker for over-current protection and short circuit fault protection, and use remote circuit breaker to manually operate the lamp on and off.Each circuit branch installs a light-control switch, and set the threshold of 100 lux for the light-control switch. When the natural illumination meet the minimum illumination requirement (> 100lux), the lights shut down the power.When natural illumination doesn't meet the lighting requirement (<100lux), the lighting automatically close.After the modification, it is resolved the outdoor lighting easily becoming a long light,and save energy. (authors)
[en] When images are acquired in bright condition, it can cause a loss of highlight details (over exposure) in bright area and a loss of shadow details (under exposure) in dark area. Over and under exposure causes a big problem when people investigate dangerous place like Fukushima nuclear power plant through the camera attached remote control robot. In this paper, we propose a method to correct the over and under exposure image to solve the problem. The image processing consists of four steps. Firstly, multiple images are acquired by alternately turning on and off each illumination which set in different positions. Then the image obtained first is defined as input image 1, the image obtained second is defined as input image 2 and the image obtained N-th is defined as input image N. Secondly, luminance of the images is corrected. Thirdly, over and under exposure regions in the image are extracted from the input image 1. Finally, the over and under exposure regions in the input image 1 are compensated by other images. The results show that the over and under exposure regions in the input image are recovered by our proposed method. (author)
[en] Since modern workers spend more than 80 per cent of their time in indoor environments, it is important to make a comfortable indoor environment in order to maintain occupational health and to improve work efficiency and productivity. Not only are new offices bigger than ever before, the internal heat and air are controlled by a central air conditioning system, which do not allow occupant control. This study evaluated indoor environments of office buildings in an effort to understand how the indoor environment influences work efficiency. The study involved the use of a survey questionnaire to obtain occupants' subjective evaluation of indoor working environments of an office building in terms of thermal comfort, lighting, noise and air quality. The survey results indicated that the indoor environment interrupts the work of many workers. Neck, eye, skin and nasal symptoms were found to be the symptoms most related to the indoor environment, with temperature and humidity posing the greatest challenge. 9 refs., 9 tabs., 7 figs