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Seville

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SEVILLE Sevilla After living up to some wonderful moments at Granada, the birthplace of the renowned Spanish poet and playwright Federico Garcia Lorca, we decided to further our coadventure through the heartland of the southern Iberian Peninsula, composed of lowlands, mountains and valleys. You’ve got it right. To arrive at Seville, we traversed the fascinating Spanish heartland. The landscape presented some vistas composed of rustic plains, lowlands, winding roads through the Sierra and then vast stretches of olive orchards. About 200 years back, a couple of decades after Napoleon’s army plundered and destroyed parts of Alhambra, an American diplomat and writer, Washington Irving and his Russian counterpart traversed the path from Seville to Granada. It was highly adventurous then, because of the fact that the transport system at that time was horse-drawn carriages and muleteers. It was such that they could ‘wander among the romantic mountains of Andalusia’ (Tales of Alhamb...

HARMFUL EFFECTS OF BLUE LIGHT

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Blue Light Hazards botid.org the best of internet directory for free! This business is listed under Technical Writing Directory The optical pathway in a human eye is connected to the visual cortex (part of the brain which mediates the sense of light) via a nervous system. The nervous system comprises photo-receptors of two types – 1) Rods; 2) Cones (named on basis of the shapes of these nerve receptors). These photo-receptors, in turn, contribute to three types of visions with image forming functions, and are important for normal daily function and life quality. Scotopic (Rod) Vision -When the field luminances lie between 10⁻⁶ cd/sqM   to 10⁻² cd/sqM . This is a vision in the darkness. The world is grey and there is no sensation of colour. Mesopic Vision - Most important vision from a Lighting Designer’s point of view. This occurs when the field luminance is raised upwards from 10⁻² cd/sqM    to 10 cd/sqM. As the luminance moves upwar...

LED in general lighting ? Not quite yet

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LED in general lighting - an update   Biswajit Sengupta Despite rapid developments in LED as an efficient source of light it has not been able to capture even 5% of the market share in general lighting application which still is being dominated by the conventional light sources. It is true that apart from high power LED chips there has been great progress in enhancing reliability of drivers and heat sinks. At least the chip manufacturers can safely claim that their products are not going to betray the useful lives declared by them. LEDs do have some unique properties which no other light source can ever have. They are highly efficient, converts almost the entire electrical energy input into light energy; requires very little power to operate ( a green energy ) as it is seen in India almost 18% of the power generated is consumed by artificial lighting ( rest of the world, particularly the developed nations, may be even higher ); smaller solar panels can be used to provid...