100‚000 years ago‚ a diverse group of hominids‚ or humanlike species‚ occupied Earth. By 30‚000 years ago‚ however‚ only Homo sapiens—the most modern species—remained. One of the most hotly debated issues in paleoanthropology‚ the study of human origins‚ focuses on how Homo sapiens evolved to outlive the other hominids. The current best explanation for the beginning of modern humans is the Out of Africa model. This holds that Homo sapiens arose in Africa and gradually replaced hominid species in
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AN INTRODUCTION TO PREDICTIVE MAINTENANCE Second Edition AN INTRODUCTION TO PREDICTIVE MAINTENANCE Second Edition R. Keith Mobley Amsterdam London New York Oxford Paris Tokyo Boston San Diego San Francisco Singapore Sydney Butterworth-Heinemann is an imprint of Elsevier Science. Copyright © 2002‚ Elsevier Science (USA). All rights reserved. No part of this publication may be reproduced‚ stored in a retrieval system‚ or transmitted in any form or by any means‚ electronic‚ mechanical
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Drilling Machine Chapter-4 Drilling machines Any component manufactured has one or more cylindrical hole in them. The process of making a hole is known a drilling. The cutting tool‚ which is used for making holes‚ is known as drill. The drill is a multipoint cutting tool. Definition: Drilling is the operation of making holes in a work piece using a drill bit. The hole is generated by the rotating drill‚ which exerts large force on the work piece clamped rigidly on the machine
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History of the Sewing Machine Before the sewing machine appeared‚ making clothes was the main occupation of half of the human race. For over 20‚000 years‚ countless hours were spent on making garments and other textiles to fulfill daily needs. The first sewing needles were made of bones and animal horns and the first thread was made of animal sinew (inventors.about.com‚ 4/16/06). The sewing machine‚ however‚ was a remarkable invention that was beneficial to all populations. More critical
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Origin and Evolution of The National Association for the Advancement of Colored People Denise Robeson HUS 121 Introduction to Human Services Instructor Thomas M. Walsh‚ MA January 23‚ 2013 The National Association for the Advancement of Colored People (NAACP) was founded on February 12‚ 1909. It is the nation’s oldest and largest civil rights based organization. The NAACP’s initial call for meeting was originated by a group of white liberals that included Mary White Ovington and Oswald
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Mexican-Americans in the past objected to being known as Chicanos? Why do so many Mexican-Americans today take pride in being Chicanos? There questions are frequently asked when the subject of the Chicano Movement comes up. This paper will seek to clarify the origins and meaning of the term Chicano and attempts to explain some of the implications of being a Chicano. A Chicano is an individual (usually with a Spanish surname) of Mexican parentage or ancestry who lives in the United States. Chicano is often used
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Simple Machines Definitions: Machine- A device that makes work easier by changing the speed ‚ direction‚ or amount of a force. Simple Machine- A device that performs work with only one movement. Simple machines include lever‚ wheel and axle‚ inclined plane‚ screw‚ and wedge. Ideal Mechanical Advantage (IMA)- A machine in which work in equals work out; such a machine would be frictionless and a 100% efficient IMA= De/Dr Actual Mechanical Advantage (AMA)- It is pretty much the opposite of
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GRINDING MACHINES Grinding is the process of removing metal by the application of abrasives which are bonded to form a rotating wheel. When the moving abrasive particles contact the workpiece‚ they act as tiny cutting tools‚ each particle cutting a tiny chip from the workpiece. It is a common error to believe that grinding abrasive wheels remove material by a rubbing action; actually‚ the process is as much a cutting action as drilling‚ milling‚ and lathe turning. The grinding machine supports and
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............................................................................. 5 3.2. Planning.....................................................................................................................5 a. Buying a Vending Machine b. Arranging Capital c.Developing Marketing Strategy * Market Segmentation * 4 P’s of Marketing Mix d.Importance of Maintainance & Insurance e.Execution f.Monitor g.Evaluation 4. Industry
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Four Forces of Evolution Mutation When an allele changes into something new or is lost Creation of a new allele (a new variant) is more common Very rare and very random‚ although certain environmental influences can have a strong impact on mutation‚ such as radiation Mutation is the only source of new genes/alleles in a species It must occur in the gametes in order to pass it on Allele Definition: An allele is an alternative form of a gene (one member of a pair) that is located at a specific
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