The Entity Relationship Diagram (ERD) depicts a conceptual data model that incorporates some of the important scientific information about the real world. It adopts a natural view that the real world consists of entities and relations (Chen‚ 1976). One objective of the ERD is to create a simple‚ easy to understand and conveniently presented data model consisting of entities‚ attributes‚ relationships and cardinalities. The model serves as tool for database design‚ where the model can facilitate communication
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Component Diagram Notations The component diagram’s main purpose is to show the structural relationships between the components of a system. In addition‚ component diagrams are useful communication tools for various groups. In creating a component diagram‚ there are different notations that can be used to show the different relationship of each component within the system. The component diagram notation set now makes it one of the easiest UML diagrams to draw: * COMPONENT A component can
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Food Web Diagram Sci/230 November‚ 2013 Desert Biome Food Web Diagram Food Web Diagram An ecosystem can be defined as a more or less self-contained function unit in ecology consisting of all abiotic and biotic
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as Phase Diagrams By _________________ _________________ Material Science Lab #11 Report Introduction The purpose of this lab is to obtain the cooling curves for tin‚ lead and various alloys of these two metals. A phase diagram will be generated from these cooling curves. When a material is heated by adding energy at a constant rate‚ the temperature of the material will increase linearly with time‚ provided a phase transformation does not occur. As temperature of the sample becomes
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POTENTIAL ENERGY DIAGRAM In physics the terms of mechanical energy usually refers to Potential energy (U) and Kinetic Energy (K). In the absence of non-conservative‚ or dissipative forces‚ these energies obey the law of conservation of energy‚ or ΔU + ΔK = 0. That is‚ when a system is only acting under the influence of conservative forces its total energy content never changes‚ the energy just converts between forms. At any point in the cycle‚ the total energy is constant‚ U + K = Umax = Kmax
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T A B The Free Body Diagram The Concurrent System Free Body Diagrams • Essential step in solving Equilibrium problems •Complex Structural systems reduced into concise FORCE systems WHAT IS A FREE BODY DIAGRAM? A FBD is a simplified representation of a PARTICLE or RIGID BODY that is isolated from its surroundings and on which all applied forces and reactions are shown. All forces acting on a particle original body must be considered‚ and equally important any force not
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CONTENTS 6 APPENDIX............................................................................................................ GLOSSARY WRD - Weibill’s Reliability Distribution RBD - Reliability Block Diagram MSG - Maintenance Steering Group RCM - Reliability Centred Maintenance EDP - Engine Driven Pump EMDP - Electrical Motor Driven Pump FTA - Fault Tree Analysis ABSTRACT The reliability analysis of Boeing 737NG’s hydraulically actuated
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How to : Data Flow Diagrams (DFDs) Data Flow Diagrams (DFDs) Data flow diagram (DFD) is a picture of the movement of data between external entities and the processes and data stores within a system Order CUSTOMER Status Message Status Data 2.0 Shipping Confirmation In-Stock Request WAREHOUSE 1.0 Shipping Order Check Status Order Data D1 Pending Orders 3.0 Issue Status Messages Order Data Payment Invoice Manage Accounts Receivable 5.0 Accounting Data Accounts Receivable Data
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1. What is an Entity Relationship Diagram? An entity relationship diagram is a graphical representation of an organisation’s data storage requirements. Entity relationship diagrams are abstractions of the real world which simplify the problem to be solved while retaining its essential features. Entity relationship diagrams are used to: identify the data that must be captured‚ stored and retrieved in order to support the business activities performed by an organisation; and identify the data required
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The Iron-Carbon Diagram There are two iron-carbon equilibrium diagrams: - stable iron-graphite Fe-Gr - metastable iron-cementite Fe-Fe3C The stable condition usually takes a very long time to develop. The metastable diagram is of more interest. Fe3C iron carbide called cementite because it is hard. Following phases exist on Fe-Fe3C diagram: - liquid solution of iron and carbon (L) - ferrite ( ) – an interstitial solid solution of carbon in Fe (bcc). At room temperature ferrite is ductile but
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