6 Pg 305 2. What is a data flow diagram? Why do systems analysts use data flow diagrams? Answers: A picture of the movement of data between external entities and the processes and data stores within a system. Systems analysts use DFDs to help in the analysis phase by accomplishing the following three things: 1. Requirements Determination 2. Requirements Structuring 3. Alternative Generation and Selection 3. Explain the rules for drawing good data flow diagrams. Answers: Process: A. No process
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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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Figure 1.0: Entity Relationship Diagram of Generic Academic Performance Monitoring System Figure 2.0: Context Diagram of Generic Academic Performance Monitoring System The figure 2.0 represents the two (2) users of the Generic Academic Performance Monitoring System namely the Administrator and the Professor. The Administrator entity shows the capability to access the system; manage account by modifying account’s profile; managing member’s account such as creating new user profile and updating
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Dependencies and Network Diagram The network diagram is a schematic representation showing the sequence and relationship/ dependency of the tasks along with their duration. All the tasks‚ except the first and the last‚ are linked with at least one predecessor and successor to have a proper sequence of work. This logical dependency between the tasks will determine afterwards the duration of the project. There are four types of dependencies which define the relation between pair tasks Finish-to-start
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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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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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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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Entity Relationship Diagram The bellow diagram is what is refered to as an "Entity Relationship Diagram". Its purpose is to show the relationship between different data in the hotel management program ‚ and the actions that are performed on it. And how data from different objects relate to each other. Legend The Data Entities represent data that will need to be stored on the system‚ in general terms. The Relationships represent actions that will occur to the Data Entities‚ or Weak Entities.
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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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