wires with beads strung on them and was one of the best calculating machines until the seventeenth century (PBS‚ 1). In 1835‚ English inventor‚ Charles Babbage came up with the idea of the Analytical Machine‚ a general purpose‚ fully programmed-controlled‚ automatic mechanical digital computer‚ which consisted of two parts‚ a calculating section and a storage section. His machine was capable of reading the punched holes in cards‚ just as the loom did (Campbell-Kelly‚ 15-17). In 1890 Herman Hollerith
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References: * P. N. Enjeti and R Martinez‚ “A high performance single phase rectifier with input power factor correction ‚”IEEE Trans. Power Electron..vol.11‚No.2‚Mar.2003.pp 311-317 * J.G. Cho‚J.W.Won‚H.S. Lee ‚ “Reduced conduction loss zero-voltage-transition power factor correction converter with low cost”‚ IEEE Trans Industrial
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Origins of the Name The word‚ Aluminium originates from the ancient Latin word for alum‚ alumen‚ which is potassium aluminum sulfate‚ meaning “bitter salt”. We pronounce the element of aluminium’s name as follows‚ al-yuh-min-ee-uhm‚ which conforms to the IUPAC pronunciation of the word‚ with the regular ‘ium’ ending of majority of the elements of the periodic table. The History Aluminium was first discovered in 1825‚ by early discoverer‚ Hans Christian Oersted in Denmark. Before this time‚ alum
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saw the development of high-power microwave emitters known as cavity magnetrons‚ the idea of using microwaves to transmit power was researched. In 1964‚ William C. Brown demonstrated a miniature helicopter equipped with a combination antenna and rectifier device called a rectenna. The rectenna converted microwave power into electricity‚ allowing the helicopter to fly. In principle‚ the rectenna is capable of very high conversion efficiencies - over 90% in optimal circumstances. Most proposed MPT systems
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CHAPTER-1 GENERAL OVERVIEW 1.1 INTRODUCTION: In an automobile headlight‚ a ’meeting’ beam (dip beam) is provided in addition to the driving beam (high beam) so as to reduce the dazzle for those approaching head-on to the vehicle. The Auto Dipping Device for a head light is intended to automatically change the Headlight Circuit to either driving beam or dip beam given a particular set of road conditions‚ without the intervention of the driver. The present practice is to operate the dip
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energy etc‚ and there are many different types of both analogue and digital input and output devices available to choose from. The type of input or output transducer being used‚ really depends upon the type of signal or process being "Sensed" or "Controlled" but we can define a transducer as a device that converts one physical quantity into another. Devices which perform an input function are commonly called Sensors because they "sense" a physical change in some characteristic that changes in
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Transistor: It also does exactly same thing as above except that it has a negative voltage on its collector and a positive voltage on its emitter. [pic] Transistor is a combination of semi-conductor elements allowing a controlled current flow. Germanium and Silicon is the two semi-conductor elements used for making it. There are two types of transistors such as POINT CONTACT and JUNCTION TRANSISTORS. Point contact construction is defective so is now out of use. Junction triode transistors
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important of these elements are silicon and germanium. Semiconductor materials are useful because their behaviour can be manipulated by the addition of impurities‚ known as doping .Doping a semiconductor with a small amount of impurity atoms greatly increases the number of charge carriers within it. When a doped semiconductor contains excess holes it is called "p-type"‚ and when it contains excess free electrons it is known as "n-type". Germanium‚ gallium arsenide‚ and silicon carbide are common dopants
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thrives to define the kilogram in relation to the Planck Constant “h”. To accomplish this redefinition‚ a consistent realization of the kilogram centred on several analysis is necessary. At the moment‚ measurement of the Planck Constant based on the Silicon Sphere Avogadro and Watt balance approaches have been concluded‚ but there exists certain disagreements in the results which mar the achievement within limit of allowable uncertainty of “2 X 10-8”.The Proposed Joint Report Project need to improve
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Dept. of Electrical and Electronic Engineering Course no.: EEE 2103 Name of the Paper: “COMPREHENSIVE STUDY OF P-N JUNCTION” Submitted to: Mr. Md. Ziaur Rahman Submitted by: Shafa Al Shahid (11.01.05.090) Abdullah al Rumi (11.01.05.091) Md. Shadman Khan (11.01.05.092) Reaz Ahmed (11.01.05.093) Saidur Rahman Mishu (11.01.05.094) Date of submission: 28.06.2012 Comprehensive Study On P-N Junction Diode Shafa Al Shahid ‚ Abdullah al Rumi‚ Md. Shadman Khan‚ Reaz Ahmed‚ Saidur
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