Advantages of leds

First off, it’s all about the lumens. Lumens are the visible light given off by a source, and they are the ultimate goal. Wattage has often been confused with lumens, thanks to how incandescent bulbs are rated (everyone knows that a 60W bulb is not as bright as a 100W one), but more efficient lighting technologies have greatly changed the relationship between wattage (essentially power usage) and lumens (light output). For example, an incandescent might operate at about 12-15 lumens-per-watt (lm/W), while an LED bulb will be in the range of 40-50, a much greater luminous efficacy...

69p aries23 29-09-2012 78 31   Download

Introduction to LEDs: How LEDs work + some points. Comparison with other sources of light. LED in communication. Blue &White LED technologies. How they are made? Their application? Brief about blue laser? Stands for light emitting diode. Semiconductor device: p-n junction forward-biased.current emits incoherent narrow spectrum light (due to recombination in transition region near the junction.) Color of the emitted light depends on the chemical of the semiconducting material used. (Near-ultraviolet, visible or infrared.)...

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Algorithms play the central role both in the science and practice of computing. Recognition of this fact has led to the appearance of a considerable number of textbooks on the subject. By and large, they follow one of two alternatives in presenting algorithms. One classifies algorithms according to a problem type. Such a book would have separate chapters on algorithms for sorting, searching, graphs, and so on. The advantage of this approach is that it allows an immediate comparison of, say, the efficiency of different algorithms for the same problem.

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Nucleic Acid Hybridization Nucleic acid hybridization is a fundamental principle in molecular biology that takes advantage of the fact that the two complementary strands of nucleic acids bind, or hybridize, to one another with very high specificity. The goal of hybridization is to detect specific nucleic acid (DNA or RNA) sequences in a complex background of other sequences. This technique is used for Southern blotting, Northern blotting, and for screening libraries (see above). Further adaptation of hybridization techniques has led to the development of microarray DNA chips.

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In recent years, great focus has been placed upon polymer thin films. These polymer thin films are important in many technological applications, ranging from coatings and adhesives to organic electronic devices, including sensors and detectors. Polymers can be prepared using chemical and/or electrochemical methods of polymerization. There are a few advantages of electrosynthesis over chemical methods.

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A-priori market segmentation designates groups of customers who are similar in terms of segmentation variable(s) that are known or believed in advance to be related to con- sumption of a company’s product, for example, demographics, purchase volume or geographic area. Segmentation variables are selected before analysis begins.

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Continuing improvements led to the furnace and bellows and provided the ability to smelt and forge native metals (naturally occurring in relatively pure form).[38] Gold, copper, silver, and lead, were such early metals. The advantages of copper tools over stone, bone, and wooden tools were quickly apparent to early humans, and native copper was probably used from near the beginning of Neolithic times (about 8000 BC).[39] Native copper does not naturally occur in large amounts, but copper ores are quite common and some of them produce metal easily when burned in wood or charcoal fires.

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The growth experience of India and other South Asian countries suggests that a “Service Revolution”—rapid income growth, job creation, gender equality, and poverty reduction led by services—is now possible. What is a service revolution? Can services be as dynamic as manufacturing? Can latecomers to development take advantage of the globalization of services? Can services be a driver of sustained growth, job creation, and poverty reduction? What kind of policies and institutions do developing countries need to benefit from services-led growth?...

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Jensen (1990) and others used empirical evidence to demonstrate that there was a link between large pay bonuses provided to executives on a performance basis and improved corporate performance . Th ese theories in part motivated the trend be- ginning in the 1990s of deliberate struc- turing of corporate executive salaries to match performance of the corporation as closely as possible, usually through options to purchase shares in the com- pany on advantageous terms off ered to the executive.

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This module provides students with a high level overview of the component architecture of Microsoft® Exchange 2000. They will learn that Exchange 2000 is designed to take advantage of Microsoft Windows® 2000. This has led to a number of fundamental architectural changes, including a more versatile information store service, placement of protocol management in the Internet Information Services, and event support for customizing mail-enabled software.

36p vuthuong 10-08-2009 44 2   Download

Applications that use HTML-based front ends benefit from the pervasive distribution of Web browsers for universal, cross-platform access. Another striking advantage of Web delivery lies in the concept of thin clients and centralized maintenance, facilitating instantaneous deployment of software updates at minimal cost. While the popularity of the Web and its advantages as a client-server platform have led to countless HTML-based applications, the development of Web applications is still mostly ad hoc.

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Cloud Computing: Implementation, Management, and Security provides an understanding of what cloud computing really means, explores how disruptive it may become in the future, and examines its advantages and disadvantages. It gives business executives the knowledge necessary to make informed, educated decisions regarding cloud initiatives. The authors first discuss the evolution of computing from a historical perspective, focusing primarily on advances that led to the development of cloud computing.

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Develop SharePoint apps using collaborative social enterprise tools Use the new Minimal Download Strategy (MDS) smart technology to consume less bandwidth Version documents, list items, and entire parts of SharePoint with improved control Use colors and styles to get a themed version of your CSS with a simple line of code Extend the client object model with enhanced search capabilities Your guide to the most significant changes in SharePoint 2013.

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Optical Transmitters The role of the optical transmitter is to convert an electrical input signal into the corresponding optical signal and then launch it into the optical fiber serving as a communication channel. The major component of optical transmitters is an optical source. Fiber-optic communication systems often use semiconductor optical sources such as light-emitting diodes (LEDs) and semiconductor lasers because of several inherent advantages offered by them.

56p khinhkha 29-07-2010 57 7   Download

The rapid growth of the portable electronics market includes ‘power-hungry’ accessories in a smaller system, which has led to the search for an alternative and advanced power source due to the limited energy density of conventional lithium-ion batteries. Table 1 lists the power demand of the different portable applications. Fuel cells promise to provide a more reliable and longer operational time than batteries. As the energy is stored as a reservoir rather than as an integral part of the power source, fuel cells have advantages over batteries.

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This publication presents agronomic reasons which have led to the development of controlled-release and stabilized fertilizers. The characteristics, the advantages and the possible disadvantages of controlled-release and nitrification/urease inhibitors are discussed. Particular attention is given to problems of legislation, registration, methodology and standardization. Leading manufacturers and their product ranges are listed.

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Universal sensitivity to our environment and environmental considerations have led to the development of projects that not only minimize GHG (Green House Gas) emissions, but also help to displace GHG emissions from existing plants as well as other emissions sources. Thus, one of the more significant advantages for gas turbine, combined cycles and gas reciprocating engines is the potential for GHG reductions as compared to less efficient systems.

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