DATA COMMUNICATION COEN 3193 Assignment No. 1 Brief History of Data Communication Submitted by: Camille A. Bonito BSCpE IV-2 Submitted to: Florinda H. Oquindo TIMELINE OF HISTORY OF DATA COMMUNICATION 1800 Telegraph defined from the Greek... TELE = Afar GRAPHOS = Write 1809 First telegraph in Bavaria. Samuel Soemmering. Used 35 wires with gold electrodes in water. Detection at distant end 2000 feet away was by the amount of gas caused by electrolysis. 1828 First telegraph in the USA
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The Evolution of Data Models The quest for better data management has led to different models that attempt to resolve the file system’s critical shortcomings. Because each data model evolved from its predecessors‚ it is essential to examine the major data models in roughly chronological order. 1.1 The Hierarchical Model A Hierarchical Database Model is a data model in which the data is organized into a tree-like structure. The structure allows representing information using parent/child relationships:
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Data Encryption Standard In 1972‚ the NBS Institute for Computer Sciences and Technology (ICST) initiated a project in computer security‚ a subject then in its infancy. One of the first goals of the project was to develop a cryptographic algorithm standard that could be used to protect sensitive and valuable data during transmission and in storage. Prior to this NBS initiative‚ encryption had been largely the concern of military and intelligence organizations. The encryption algorithms‚ i.e.‚ the
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BC - ABAP Dictionary Release 4.6C HELP.BCDWBDIC BC - ABAP Dictionary SAP AG Copyright © Copyright 2001 SAP AG. All rights reserved. No part of this publication may be reproduced or transmitted in any form or for any purpose without the express permission of SAP AG. The information contained herein may be changed without prior notice. Some software products marketed by SAP AG and its distributors contain proprietary software components of other software vendors. Microsoft ‚ WINDOWS
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DISCRETE SEMICONDUCTORS DATA SHEET book‚ halfpage BC546; BC547; BC548 NPN general purpose transistors Product specification 1997 Mar 04 Supersedes data of September 1994 File under Discrete Semiconductors‚ SC04 Philips Semiconductors Product specification NPN general purpose transistors BC546; BC547; BC548 FEATURES Low current (max. 100 mA) Low voltage (max. 65 V). APPLICATIONS
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DATA FLOW DIAGRAM Group#7 Nugao Oserin Obongen The Data Flow Diagram (DFD) • a graphical representation of the flow of data through an information system. It enables you to represent the processes in your information system from the viewpoint of data. The DFD lets you visualize how the system operates‚ what the system accomplishes and how it will be implemented‚ when it is refined with further specification. • Data flow diagrams are used by systems analysts to design information-processing systems
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"A grim specter has crept upon us almost unnoticed‚ and this imagined tragedy may easily become a stark reality we all shall know" (Carson 3). "Given time—time not in years but in millennia—life adjusts‚ and a balance has been reached. For time is the essential ingredient; but in the modern world there is no time" (Carson 6). "The chemicals to which life is asked to make its adjustment are no longer merely the calcium and silica and copper and all the rest of the minerals washed out of the rocks
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Analyzing and Interpreting Data QNT/351 September 16‚ 2014 Analyzing and Interpreting Data BIMS management team has been facing a major dilemma of high turnover and extremely low employee morale. BIMS management team has asked Team B to help identify the main cause of the high turnover and low morale and propose an acceptable solution that will result in a decrease of both. Data Collection Conclusion In the past few months we at BIMS have learned‚ thru the drop in employees that the company’s
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Qantas Data Book 2012 DISCLAIMER The information contained in this investor Data Book is intended to be a general summary of Qantas Airways Limited (Qantas/Qantas Group) and its activities as at 17 October 2012 or otherwise the date specified in the relevant information and does not purport to be complete in any respect. The information in this document is not advice about shares in Qantas (or any other financial product)‚ nor is it intended to influence‚ or be relied upon by‚ any person in
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Statistical Data Analyses Graeme Ferdinand D. Armecin‚ MHSS Outline of Presentation Overview of Research Designs Functions of Statistics Sampling Principles of Analysis and Interpretation (with Computer Package) – Descriptive Statistics – Inferential Statistics Graeme Ferdinand D. Armecin‚ MHSS Statistical Data Analyses Purposes of Research Design Exploratory/Descriptive Research design – Basic or fundamental in the research enterprise – What is going on? –
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