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 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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Introductory Biology‚ Biology 1407 MWF 11:00. TAMU-CC. Working version of the 1st lecture exam‚ as of 19 January 2014 1. Science can prove hypotheses to be false because: 2. In a population: phenotype Average number of offspring per individual Very small nose 5.5 Small nose 6.0 Medium size nose 10.7 Large nose 20.7 What is the relative fitness of organisms with small noses? 3. In the above population‚ assuming that at one time the population followed a normal curve
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Entity-Relationship Diagrams (ERD) Data models are tools used in analysis to describe the data requirements and assumptions in the system from a top-down perspective. They also set the stage for the design of databases later on in the SDLC. There are three basic elements in ER models: Entities are the "things" about which we seek information. Attributes are the data we collect about the entities. Relationships provide the structure needed to draw information from multiple entities. Generally
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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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Biology Notes: Threats to biodiversity in MA 1. Climate change: temp‚ sea levels‚ precipitation 2. Non climate threats such as habitat loss‚ habitat fragmentation‚ and invasive species and air and water pollution Fragmentation: often due to man (dams‚ roads‚ and general development) Elements of biodiversity: Species‚ ecosystems & landscapes Mammals from bats to bears Bats got the white nose fungus which caused the bats to die and the insect population flourished because the bats main job
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Topology Diagram Topology Name Logical Characteristics Physical Characteristics Star Data passes through the hub to reach other devices on the network. Several devices having its own cable that connects to a central hub‚ or sometimes a switch‚ or even a Multi-station Access Unit (MAU). Data passes through the hub to reach other devices on the network. Ring Information is passed from one computer to another in either clock-wise direction or counter clock-wise direction and
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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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Flowcharts Guidelines for Drawing System Flowcharts PROBLEMS CASE ANALYSES The Berridge Company FreezeTime‚ Inc. The Dinteman Company Lois Hale and Associates PROCESS MAPS AND DATA FLOW DIAGRAMS Process Maps Guidelines for Drawing Process Maps Data Flow Diagrams Guidelines for Drawing Data Flow Diagrams REFERENCES AND RECOMMENDED READINGS ANSWERS TO TEST YOURSELF OTHER DOCUMENTATION TOOLS Program Flowcharts Decision Tables Software Tools for Graphical Documentation and SOX Compliance
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Rubyna May L. Espiritu Sir Adrian Guinto BSEDSS 1-1N November 15‚ 2012 The Characteristics of Life There are many properties or the signs of life that the living organisms have. In the book of biology of Mrtinez and Nazareno‚ there are nine characteristics of life just said and those are : a. Living things are highly organized and contain many complex chemical substances ; b. Living things are made up of one or more cells‚ which are
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