21 research outputs found
Quantitative Evaluation of Visual Function 12 Months after Bilateral Implantation of a Diffractive Trifocal IOL
Energy efficient innovative lighting and energy supply solutions in developing countries
The vast majority of the rural population in the de veloping countries is out of reach of electricity and hence has to depend on the tradi tional fuels to fulfil the daily energy needs. Providing grid electricity to the rural areas of ma ny developing countries is a very difficult task due to the geographical complexity and lack of fina ncial resources. The paper explains the use of different renewable energy sources in combination w ith efficient lighting technology as a realistic option to provide clean lighting services to develo ping countries. The application of Light Emitting Diodes and renewable energy sources has be en a sustainable solution to the basic lighting needs of rural people. The paper also pres ents a comparison of costs between available renewable energy technologies
Replacing fuel based lighting with light emitting diodes in developing countries: Energy and lighting in rural Nepali homes
More than one quarter of the world’s population, who does not have access to electric light, live in the developing countries. Nepal is one of these countries, where the people in the remote rural areas have to rely on fuel based lighting to bring minimal lighting services in their homes. This paper reviews the quality of lighting, energy and health issues due to the use of fuel based lighting in rural Nepali villages. Recommendations are given on the amount of light needed as the first time electric lighting services in those remote places. The measurement results show that LED technology can bring necessary light in these rural homes with least energy use and it is the potential technology to replace fuel based lighting in a sustainable way. Replacing fuel based lighting by white LEDs can also contribute to the overall development of the underprivileged and underdeveloped communities by helping to improve the health, education and life expectancy of the people as well as income generation
Mesopic models - from brightness matching to visual performance of night-time driving: a review
Mesopic spectral sensitivity functions based on visibility and recognition contrast thresholds
Mesopic models—from brightness matching to visual performance in night-time driving: a review
Mesopic models : from brightness matching to visual performance in night-time driving: a review
At present, suitable methods to evaluate the visual effectiveness of lighting products in the mesopic region are not available. The majority of spectral luminous efficiency functions obtained to date in the mesopic range have been acquired by heterochromatic brightness matching. However, the most recent studies in the mesopic field have adopted a task performance-based approach. This paper summarizes the major mesopic models proposed so far, presenting in detail the experimental conditions of these studies. The authors represent a research consortium which has adopted the task performance-based approach for night-time driving in which mesopic visual performance has been divided into three subtasks. Data for each sub-task will be generated by using a set of common parameter values and 120 observers. The approach and methods used by the consortium are presented. © The Chartered Institution of Building Services Engineers 2005