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UML example

UML or Unified modelling language is the best tool for modelling object oriented systems. As we know, in objet oriented modelling and design, we identify objects (entities)within the system and analyze how they interact with each other and thus design an interactive model preserving their individual properties, behavior as well as publicizing their public attributes…

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ERD examples

ERD or Entity relationship diagram is the most common database design and modelling tool used in System Design phase. The diagram basically represents all data entities of the targeted system, their attributes and relationships. Database modeller represents ERD in various levels of details such as Context Data Model, Key based model and Fully attributed model….

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DFDs example

Data Flow Diagram is the widely used system design tool which aids in depicting flow of logic and data (commonly called process flow) within the targeted system, in various levels of detail. Level 0 DFD is usually called ‘Context Diagram’ and it gives the highest level view. Starting from the black box in Context Diagram,…

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Use Case Building – An example

Use cases are one of the excellent tools for representing functional requirements of a system. Use case modelling refers to modelling of system’s functions in terms of business events (use cases), who initiated the events (actors) and how does system reacts to those events (Whitten J.L, 2007). Use case models are usually represented as use…

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Should countries like the United States push for agenda items like freedom of expression, intellectual property protection, and cybercrime prevention?

The freedom of expression, being one of the firmly stated and affirmed right in the US constitution, I think the question refers to effecting in a global scenario. Freedom of expression touches most sensitive areas such as religion, which has a soft corner for. Considering the current world situation, I think pushing for such agendas…

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What is IT?

We have seen so much about IT and all of us have been a part of it by some means or other. We all know what IT refers to and what are its applications. I have been trying to define what is IT or Information Technology, since some time. This is puerly a personal effort…

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Information Management and career levels

Deepesh JosephAugust 2006 Information Management (IM) refers to any activity that leads to effective collection, storage, retrieval and analysis of information by focusing on business strategy and by continuously improving business competitiveness and adaptability. The ultimate goal of any IM job is to add up to the combined efforts to meet the required business strategy….

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Compare and contrast data warehouse principles

Operational Vs Informational system : Operational Systems are those which are based on current data and thus supports current/day-to-day functioning of a business. Informational Systems on the other hand are based on historical information and thus supports complex data mining/analysis and decision making. The core difference lies in the way queries are run to process/analyze…

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Various kinds of Database Systems

a. Homogeneous vs. heterogeneous distributed database system Homogeneous database systems involve similar databases distributed over the network (on separate machines). Example of homogeneous database system is an enterprise’s nation-wide ERP system which comprises of distributed databases, all of which are Oracle. Heterogeneous database systems on the other hand are distributed database systems that consist of…

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Pros and Cons of normalizing data into 3NF form

Deepesh Joseph February 2009 The main purpose of normalization is to reduce data redundancy and avoid inconsistent data. Normalization leads to separation of unrelated entities into separate entities. In effect, normalization leads to clean database design. Since we do not store redundant data, we save storage space and save resources to maintain (update, delete) redundant…

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Using a Steel Rule

Steel Rule is a measuring instrument used as a standard for measuring materials. It is made of stainless steel. The most convenient for the general purpose is a 12 inch rule as shown in below schematic – For small jobs, a pocket rule 6 inch long is very useful. In measuring, the graduation should be…

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Scriber

A scriber is a marking tool. It has a straight pointed tip and a bent pointed tip. It is used for marking and drawing straight lines by using a steel rule. Schematic for a Scriber is as shown below –

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Hammers

There are various types of hammers in use. The most commonly used hand hammer is Ball-Pane hammer. Other types are Cross Pane hammer and Straight edge hammer. Schematic of a Ball pave hammer is as shown below – Hammers are made of cast steel. A wooden handle is fixed on the hammer to use it…

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Pipe Wrench

Pipe Wrench is a type of adjustable spanner which has wide use in tightening or loosening nuts and taps. It has one fixed jaw and one movable jaw and a handle which is a continuation of the movable jaw. The nut or tap to be loosened or tightened is held tightly between the jaws and…

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Bench Vice

Vice is a device for holding work. There are various types of vices and the most common one is the Bench Vice. It consists of a movable jaw. Movable jaw has a square or butter threaded spindle. There is a spindle handle also by which the movable jaw can be brought to any desired position. A…

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How to use a File

File is another cutting tool and is available in a variety of lengths, grade cuts and shapes. Files are made of high carbon steel and is attached to a handle. The file has a series of teeth set at an angle which cut the work on the forward stroke. Files have generally 3 types of…

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How to use a Hack-Saw

Hack-Saw is a cutting tool used for cutting metal pieces, wide grooves etc. It consists of a metal frame fitted with handle made of wood. A blade of suitable size is fitted to the frame as shown below – Usually the blade manufactured are 8inch, 10inch and 12inch, The blade has bent teeth. As the…

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How to use a Centre Punch?

Centre Punch is the commonest of all punches and is a steel rod 90 – 150 mm long and 8 – 13 mm in diameter. It is used to make marls at the centers of holes which are to be drilled and to make marks on a line through which a metal is to be…

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Try Square

Try Square is used to test the smoothness of surfaces and to test the perpendicularity of a surface with respect to an adjacent one. It consists of a stock and blade fixed together at 90 degree to each other. The stock acts as a fence and the blade as a guide in marking.