C++ Program

The Java Runtime Environment (JRE) provides the libraries, the Java Virtual Machine, and other components to run applets and applications written in the Java programming language. In addition, two key deployment technologies are part of the JRE: Java Plug-in, which enables applets to run in popular browsers; and Java Web Start, which deploys standalone applications over a network. (a) Java Plug-in : Java Plug-in technology, included as part of the Java Runtime Environment, Standard Edition (Java SE), establishes a connection between popular browsers and the Java platform. This connection enables applets on Web sites to be run within a browser on the desktop. (b) Java Web Start : Using Java Web Start technology, standalone Java software applications can be deployed with a single click over the network. Java Web Start ensures the most current version of the application will be deployed, as well as the correct version of the Java Runtime Environment (JRE).

Java is a general-purpose, object-oriented programming language. We can  develop two types of Java programs : Stand alone Applications : Programs written in Java to carry out certain  tasks on a stand alone local computer.  Executing stand alone java  programs involves two steps : (a) Compiling through javac compiler. (b) Executing the byte code using java interpreter.  Web Applets : Programs that are developed for Internet based   applications. An applet located on a distant computer (Server) can be   downloaded via Internet and executed on a local computer (Client) using   a java capable browser. From the user‟s point of view, Java applications can be compared to   compiled C programs since they are started from a command line just like   any compiled program would be started. However, there is a major  difference: Java applications, as well as applets, are interpreted.  Applications are started on the command-line by calling the Java   Interpreter with the name of the

The term exception is shorthand for the phrase "exceptional event." Definition : An exception is an event, which occurs during the execution of a program that disrupts the normal flow of the program's instructions.  When an error occurs within a method, the method creates an object and hands it off to the runtime system. The object, called an exception object, contains information about the error, including its type and the state of the program when the error occurred. Creating an exception object and handing it to the runtime system is called throwing an exception. After a method throws an exception, the runtime system attempts to find something to handle it.  Some of the predefined exception classes are :  ArithmeticException, ArrayIndexOutOfBoundException, IOException etc.

Abstract Methods and Classes : An abstract class is a class that is declared abstract—it may or may not include abstract methods. Abstract classes cannot be instantiated, but they can be subclassed. An abstract method is a method that is declared without an implementation (without braces, and followed by a semicolon), like this : abstract void moveTo(double deltaX, double deltaY); If a class includes abstract methods, the class itself must be declared abstract, as in: public abstract class GraphicObject { // declare fields // declare non-abstract methods abstract void draw(); } When an abstract class is subclassed, the subclass usually provides implementations for all of the abstract methods in its parent class. However, if it does not, the subclass must also be declared abstract. When an Abstract Class Implements an Interface : A class that implements an interface must implement all of the interface's methods. It is possible, however, to define a class that does not implement al

Packages Many times when we get a chance to work on a small project, one thing we intend to do is to put all java files into one single directory. It is quick, easy and harmless. However if our small project gets bigger, and the number of files is increasing, putting all these files into the same directory would be a problematic for us. In java we can avoid this sort of problem by using Packages. Packages are nothing more than the way we organize files into different directories according to their functionality, usability as well as category they should belong to. Packaging also help us to avoid class name collision when we use the same class name as that of others. For example, if we have a class name called "Vector", its name would crash with the Vector class from JDK. However, this never happens because JDK use java.util as a package name for the Vector class (java.util.Vector). So our Vector class can be named as "Vector" or we can put it into another packa

Wrapper classes are used to represent primitive values when an Object is required. The wrapper classes are used extensively with Collection classes in the java.util package and with the classes in the java.lang.reflect reflection package. Wrapper classes has the following features :  One for each primitive type: Boolean, Byte, Character, Double, Float, Integer, Long, and Short. Byte, Double, Float, Integer and Short extend the abstract Number class. All are public final i.e. cannot be extended. Get around limitations of primitive types. Allow objects to be created from primitive types.  All the classes have two constructor forms :  a constructor that takes the primitive type and creates an object eg Character(char), Integer(int).  a constructor that converts a String into an object eg Integer("1"). Throws a NumberFormatException if the String cannot be converted to a number.

Serialization involves saving the current state of an object to a stream, and restoring an equivalent object from that stream. The stream functions as a container for the object. Its contents include a partial representation of the object's internal structure, including variable types, names, and values. The container may be transient (RAM-based) or persistent (disk-based). A transient container may be used to prepare an object for transmission from one computer to another. A persistent container, such as a file on disk, allows storage of the object after the current session is finished. In both cases theinformation stored in the container can later be used to construct an equivalent object containing the same data as the original. For an object to be serialized, it must be an instance of a class that implements either the Serializable or Externalizable interface. Both interfaces only permit the saving of data associated with an object's variables. They depend on the class d

The name "garbage collection" implies that objects no longer needed by the program are "garbage" and can be thrown away. A more accurate and up-to-date metaphor might be "memory recycling." When an object is no longer referenced by the program, the heap space it occupies can be recycled so that the space is made available for subsequent new objects. The garbage collector must somehow determine which objects are no longer referenced by the program and make available the heap space occupied by such unreferenced objects. In the process of freeing unreferenced objects, the garbage collector must run any finalizers of objects being freed. In addition to freeing unreferenced objects, a garbage collector may also combat heap fragmentation. Heap fragmentation occurs through the course of normal program execution.  New objects are allocated, and unreferenced objects are freed such that free portions of heap memory are left in between portions occupied by live ob

The Java programming language is strongly-typed, which means that all variables must first be declared before they can be used. This involves stating the variable's type and name: int gear = 1; Doing so tells your program that a field named "gear" exists, holds numerical data, and has an initial value of "1". A variable's data type determines the values it may contain, plus the operations that may be performed on it. In addition to int, the Java programming language supports seven other primitive data types. A primitive type is predefined by the language and is named by a reserved keyword. Primitive values do not share state with other primitive values.  The eight primitive data types supported by the Java programming language are :  Byte : The byte data type is an 8-bit signed two's complement integer. It has a minimum value of -128 and a maximum value of 127 (inclusive).  Short : The short data type is a 16-bit signed two's complement intege

Java Virtual Machine : A Java Virtual Machine (JVM) is a set of computer software programs and data structures which use a virtual machine model for the execution of other computer programs and scripts. The model used by a JVM accepts a form of computer intermediate language commonly referred to as Java bytecode. This language conceptually represents the instruction set of a stack-oriented, capability architecture. Java Virtual Machines operate on Java bytecode, which is normally (but not necessarily) generated from Java source code; a JVM can also be used to implement programming languages other than Java. For example, Ada source code can be compiled to Java bytecode, which may then be executed by a JVM. JVMs can also be released by other companies besides Sun (the developer of Java) -- JVMs using the "Java" trademark may be developed by other companies as long as they adhere to the JVM specification published by Sun (and related contractual obligations).

Java and the World Wide Web : A significant advance in Web technology was Sun Microsystems' Java platform. It enables Web pages to embed small programs (called applets) directly into the view. These applets run on the end-user's computer, providing a richer user interface than simple Web pages. Java client-side applets never gained the popularity that Sun had hoped for a variety of reasons, including lack of integration with other content (applets were confined to small boxes within the rendered page) and the fact that many computers at the time were supplied to end users without a suitably installed Java Virtual Machine, and so required a download by the user before applets would appear. Adobe Flash now performs many of the functions that were originally envisioned for Java applets, including the playing of video content, animation, and some rich UI features. Java itself has become more widely used as a platform and language for server-side and other programming.

A digital computer uses binary number system for its operation. In the binary system there are only 2 digits, 0 and 1. The manipulation of binary information is done by logic circuit known as logic gates. The important logical operations which are frequently performed in the design of a digital system are: (1) AND (2) OR (3) NOT (4) NAND (5) NOR and EXCLUSIVE OR. An electronic circuit which performs a logical operation is called a logic gate. Digital multiplexer A digital multiplexer has N inputs & only one output. By applying control signals any one input can be made, available at the output terminal. It‟s called data sector.  Combinational & Sequential Circuits There are two types of logic circuits, Combinational & Sequential. A combinational circuit is one in which the state of the O/P at any instant is entirely determined by the states of the I/P‟s at that time. Combinational circuits are those logic circuits whose operation can be completely describ

All Web pages are created in a standard format called hypertext markup language, or HTML for short. When you create or save a document as a web page, it is given a filename ending with .htm or .html, indicating that it is an HTML file. An HTML document actually contains nothing but plain text—images, sounds and other non-text elements are stored in separate files. You can look at the HTML code of any web page in your web browser : In Netscape Navigator, choose the View > Page Source command. In Internet Explorer, choose View > Source. The ATRC(Adaptive Technology Resource Centre) played an active consultation role in the design of an accessible HTML authoring tool. Recently, SoftQuad announced the release of version 4.0 of their HoTMetaL HTML authoring package. For the first time in a commercial HTML authoring tool, this package includes features to encourage and aid Web authors in the production of accessible HTML documents. The ATRC played an active consultation role in the

Horizontal Rule (HR) : The HR element is a divider between sections of text; typically a full width horizontal rule or equivalent graphic. For example : <HR> <ADDRESS>February 8, 1995, CERN</ADDRESS> </BODY> Image (IMG) : The IMG element refers to an image or icon via a hyperlink. HTML user agents may process the value of the ALT attribute as an alternative to processing the image resource indicated by the SRC attribute. Attributes of the IMG element : ALIGN : Alignment of the image with respect to the text baseline. `TOP' specifies that the top of the image aligns with the tallest item on the line containing the image. `MIDDLE' specifies that the center of the image aligns with the baseline of the line containing the image. `BOTTOM' specifies that the bottom of the image aligns with the baseline of the line containing the image. ALT : Text to use in place of the referenced image resource, for example due to processing constraints or user pref

Elements are the basic structure for HTML markup. Elements have two basic properties: attributes and content. Each attribute and each element's content has certain restrictions that must be followed for an HTML document to be considered valid. An element usually has a start tag (e.g. <element-name>) and an end tag (e.g. </element-name>). The element's attributes are contained in the start tag and content is located between the tags (e.g. <element-name attribute="value">Content</element-name>). Some elements, such as <br>, do not have any content and must not have a closing tag. Listed below are several types of markup elements used in HTML. Structural markup describes the purpose of text.  For example, <h2>Golf</h2> establishes "Golf" as a second-level heading, which would be rendered in a browser in a manner similar to the "HTML markup" title at the start of this section. Structural markup does not den

HTML, an abriviation of HyperText Markup Language, is the predominant markup language for web pages. It provides a means to describe the structure of text-based information in a document — by denoting certain text as links, headings, paragraphs, lists, and so on — and to supplement that text with interactive forms, embedded images, and other objects. HTML is written in the form of tags, surrounded by angle brackets. HTML can also describe, to some degree, the appearance and semantics of a document, and can include embedded scripting language code (such as JavaScript) which can affect the behavior of Web browsers and other HTML processors. Definition : The Hyper Text Markup Language (HTML) is a simple data format used to create hypertext documents that are portable from one platform to another. HTML documents are SGML documents with generic semantics that are appropriate for representing information from a wide range of domains. HTML is also often used to refer to content in speci

Job Description Openings are for Technical Support Officers for WIPRO BPO. Freshers/ Graduates/ Undergraduates with excellent communication skills apply willing to work in Night. shifts Profile will include technical Troubleshooting. Sal upto 20k + Free Cabs. Salary:INR 1,75,000 - 2,75,000 P.A Industry: BPO / Call Centre / ITES Functional Area: ITES, BPO, KPO, LPO, Customer Service, Operations Role Category:Voice Role:Associate/Senior Associate -(Technical) Keyskills:Tech Support, Graduate, technical support executive, technicalsupport, technical support engineer, helpdesk, it helpdesk, tsr, voice support, bba, bca, bsc, ba Desired Candidate Profile Education: (UG - Any Graduate - Any Specialization) AND (PG - Any Postgraduate - Any Specialization) AND ( Doctorate - Any Doctorate - Any Specialization) BA/ BBA/  BCA / BCOM/ BSC Graduates/ Undergraduates with excellent communication skills apply willing to work in Night. shifts Profile will include te

KANPUR: The students will get admission on first come first serve basis in various professional courses of Chhatrapati Sahuji Maharaj University (CSJMU) in the academic session 2013-14. This decision was taken in the meeting of academic council held on Saturday. CSJMU vice-chancellor Ashok Kumar and HoDs of various professional courses decided not to conduct the entrance tests for courses which had received less number of applications in 2013-14 academic session. The students will get direct admissions. The HoDs will form a merit list. On its basis, allotment of seats will be done. The students will be informed about their admissions. The academic council committee also decided to conduct entrance test for around 28 courses offered by CSJMU which got many applicants.

BERHAMPUR: With admission season round the corner,  Berhampur  University (BU) authorities have sounded alert to students and their parents to verify the genuineness of institutes before taking admission. The alert came against the backdrop of several unscrupulous institutes thriving in southern  Odisha . "We have advised students and their parents to verify the status of government recognition and university affiliation of colleges or institutes and the courses offered by them before taking admission," said vice- chancellor of the university J K Mohapatra. "The university will not be held responsibility for conduct of examinations during 2013-14 session for courses in the institutes which don't fulfill the statutory requirement of government recognition and university affiliation," said registrar B P Rath in a recent notification.

PANAJI: The high court of Bombay at Goa has upheld the provisions of the Goa University ordinance that denies benefit of gracing to allow a student to pass in an individual subject in  the Bachelor  of Computer Applications (BCA) course.  A division bench comprising Justice RP Sondurbaldota and Justice UV Bakre observed, "If one reads the objective of the programme, the absence of gracing can be justified. The objective is 'to produce employable IT workforce, that will have sound knowledge of IT and business fundamentals that can be applied to develop and customize solutions for small and medium enterprises (SMEs)'."  While stating that there would be a question mark about the "sound knowledge" of the subject by a student who has cleared the subject through gracing, the high court opined that if the university decides to have a system of evaluation by doing away with the provision of grace marks it would be a matter of its academic policy. 

Sr. No. Subject Name Syllabus Sem./Sess./Year 1 Language - I Not Available 1 2 English - I Not Available 1 3 Digital Computer Fundamentals Syllabus 1 4 Programming Language COBOL Syllabus 1 5 Allied – I Allied  Mathematics Syllabus 1 6 Practical – I Programming in COBOL Record Syllabus 1 7 System Analysis and Design Syllabus 2 8 Relational Data  Base Management System Syllabus 2 9 Programming Language C and Data Structure Syllabus 2 10 Object Oriented Programming with C++ Syllabus 2 11 Allied –II Management Accounting Syllabus 2 12 Practical – II Programming in C and C++ Using Data Syllabus 2 13 E-Commerce Syllabus 3 14 Operating System Syllabus 3 15 Programming Language VISUAL BASIC Syllabus 3 16 Programming Language JAVA and JAVA SCRIPT Syllabus 3 17 Practical – III Programming in VISUAL BASIC Record Syllabus 3 18 Practical – IV Programming in JAVA and JAVA SCRIPT Syllabus 3

Bachelor of Computer Application (BCA) BCA (60 Seats) Bachelor of Computer Applications (BCA) is the real opening path for those 12th passed students who have a desire to develop as an IT professional. The course has a global focus on its curricula. Lot of emphasis is laid on latest computer applications through different software. The Institute is maintaining a high standard of teaching in classrooms and practicals in computer laboratories with highly qualified and experienced faculty. Eligibilty 12th Science or Commerce pass with English and one of the following subjects- Mathematics/Statistics/Business Maths. For more information on bachelor of computer application (BCA) please call us today: +­91-120- 2766468, 2768492, 2766554, +­91 9717395321, +­91-9717395322, +­91-9717395323, +­91-9560290018, +­91-9560290513, (Ghaziabad, UP)

Computer Lab/ System Assistant Footwear Design & Development Institute (FDDI) Address:  FDDI, A - 10 / A, Sector - 24 NOIDA - 201 301 Gautam Budh Nagar Postal Code:  201301 City  Noida State  Uttar Pradesh Educational Requirements:  MCA/BCA/ M.sc/B.Sc with 1 Year Diploma course in Computers with min. 2 years experience in computer hardware & networking. Preference will be given to candidates having teaching experience in the relevant area. Details will be available at:  http://www.fddiindia.com/jobs-new/jobs_nonaca_30042013.html No of Post:  04 How To Apply:  Applications should be sent to Footwear Design & Development Institute (FDDI) office. Send your fully filled applications to The Dy.Manager (Admin & Pers) FOOTWEAR DESIGN & DEVELOPMENT INSTITUTE (Ministry of Commerce & Industry) A-10A, Sector-24, NOIDA-201301. Last Date:  30 May 2013 For more Government Jobs visit  Sarkari Naukri

Job Details-Assistant Manager/ Deputy Manager Eligibility: BE/ B.Tech - (CSE/ IT/ ISE/ EEE/ ECE)/ MCA candidates from  2012 batch  with an aggregate of 60% and above. Location :  Bangalore Last Date:  16 th  May 13 Hiring Process:  Written-test, Face to Face Interview Job Description : Selected candidate would be working in a Techno Functional role supporting all business/enterprise/support applications. Should be able to handle Incidents & Support projects. Should have strong problem solving skills, be flexible and a quick learner. Responsible for performing application maintenance activities. Good communication skills. Skills Set :  Java, .NET, Oracle/ MS SQL-Server programming Salary : A+ N.B : Applications are invited through Job Mentor  only. NOTE :  Recruitments through Freshersworld.com only, Candidates with a valid call letter will be permitted to take up an interview. Apply Now Applications Received : 1665 Source :- http://jobs.fre

Eligibility :  BSc, Diploma Location :  Delhi Job Category :  BSc/BCA/BCM, Defence, Diploma, Govt Sector, Others Last Date : 27 May 2013 Job Type :  Full Time Hiring Process :  Written-test Job Details Advertisement No.: CEPTAM-06 DRDO-  Centre for Personnel Talent Management (CEPTAM), invites applications for the post of  Senior Technical Assistant 'B'/ Technician 'A'  www.freshersworld.com Sl. No. Name of the Post Qualification Nos. of Post 1 Senior Technical Assistant 'B' B.Sc./ 3 years Diploma in Engineering in specified subjects/disciplines 360 2 Technician 'A' 10th Class Pass with ITI in specified trades 223 3 Assistant (Hindi), Store Assistant 'A', Admin Assistant 'A', Civilian Driver 'A', Security Assistant 'A', Fire Engine Driver, Fireman Varied ( see details in the advertisement ) 261

THE INDIAN NAVY Become a Permanent Service Commissioned (PSC) Officer in the Logistics Cadre and Short Service Commission (SSC) Officer in Education Branch and Air Traffic Control (ATC), Course Commencing – December 2013 Applications are invited from unmarried male Indian citizens for Permanent Service Commission (PSC) in the Logisitcs Cadre of Executive Branch and unmarried Male/ Female for Short Service commission in Education Branch and ATC of the Indian Navy for Course commencing December 2013 at Naval Academy (NAVAC) Ezhimala, Kerala. : Logistics / Works (Only for male)  : B.Com./ M.Com./ BA/ MA / BBA/ MBA/ BBM/ BCA/ MCA/ B.Sc. (IT)/ M.Sc. (IT)/ B.Tech./ BE (Any discipline)/ Graduate Degree with Post Graduate Diploma/ Degree in Materials Management/ ICWA/ CA Education  : M.Sc. Physics with Maths in B.Sc./ M.Sc. Physics with Maths in B.Sc./ MCA/ M.Sc. (Operational Research/ Analysis)/ M.Sc. (Mateorology/ Oceanography/ Atmospheric Sciences)/ MA (English or History) OR BE/ B.

  Eligibility for BCA Course: ·           Candidate must have passed 12 th  standard ·           Student  should have at least 50% marks in 12 th  standard ·           Student must have P.C.M. subjects in 12 th  standard ·           Student must be a citizen of India. Also preference is given to those who are residents of the state. Some institute do keep an age limit of 17 years. 1.    Acharya Institute of Management and Sciences ,(AIMS) Bangalore, India 2.    Satya Institute of Media and Management Lucknow, India 3.    Indian Institute of Management & Commerece (IIMC) Hyderabad, India 4.    Prestige Institute of Management and Research Indore, India 5.    Apeejay Institute of Management Jalandhar, India 6.    Aryans Group of Colleges (AGC) Mohali, India 7.    JK Business School (JKBS) Gurgaon - Delhi/NCR, India 8.    Prestige Institute Of Management Gwalior, India 9.    Indian Academy Group of Institutions Bangalore, India

Embedded SQL is a method of combining the computing power of a programming language and the database manipulation capabilities of SQL. It allows programmers to embed SQL statements in programs written in C/C++, Fortran, COBOL, Pascal, etc. Embedded SQL statements are SQL statements written within application programming languages and preprocessed by a SQL preprocessor before the application program is compiled. There are two types of embedded SQL: static and dynamic. The SQL standard defines embedding of SQL as embedded SQL and the language in which SQL queries are embedded is referred to as the host language. A popular host language is C. The mixed C and embedded SQL is called Pro*C in Oracle and Sybase database management systems. Other embedded SQL precompilers are Pro*COBOL, Pro*FORTRAN, Pro*PL/I, Pro*Pascal, and SQL*Module (for Ada).

Rajasthan Public Service Commission (RPSC) Ajmer (Rajasthan) RPSC invites Online application for following posts of Programmers through a competitive examination for Department of Information Technology and Communication, and for Prison Department Government of Rajasthan : Programmer :  173 posts, Age : 21-35 years as on 01/01/2014, Pay Scale : Rs. 9300-34800 Grade Pay Rs. 4200/-, Qualification :  B.E./B.Tech./M.Sc. in Information Technology or Computer Science or Electronics and Communications OR MCA OR M.Tech. degree in Information Technology or Computer Science or Electronics and Communications OR MBA (IT) Assistant Jailor  : 42 posts,  Age  : 21-26 years as on 01/01/2014,  Pay Scale  : Rs. 5200-20200 Grade Pay Rs. 2000/-, Qualification :  Graduation or appearing in final year of graduation. Application Fee : Rs. 350/- (Rs. 250/- for OBC and Rs.150/- for SC/ST) plus Rs.40/- online portal charges. How to Apply :  Apply Online at RPSC website on or before 30/05/2013 12.

A database which resides all of its data centralized and on one machine or some machines which are connected together but looks one for the users looking from outside. And whoever wants to use data, he picks data from there and uses and saves again there. While Distributed databases can be defined as a collection of multiple, logically interrelated databases distributed over a computer network. And distributed database management system (DDBMS) manages the distributed databases and makes this distribution transparent to the user. All the database must be logically related that are managed by DDBMS (distributed database management system). The distributed databases are not just the ‗collection of files‘ stored individually at different network nodes. Rather to form DDBS (distributed databases) all the files should be logically related and there should be structures among those files. In the case of distributed databases, data must be physically distributed across the network nodes ot

Centralized Databases A "centralized DBMS"is a DBMS where all the data within the database is stored on a single computer, usually the secondary storage device of the computer. In a centralized DBMS, as the number of transactions executing on the DBMS increases, performance of the DBMS significantly decreases and becomes a drain on the overall performance of the computer

There is mainly 2 database   ORDBMS and OODBMS An Object-Relational Database (ORD) or Object-Relational Database Management System (ORDBMS) is a database management system similar to a relational database, but with an object-oriented database model: objects, classes and inheritance are directly supported in database schemas and in the query language. In addition, it supports extension of the data model with custom data-types and methods. One aim for this type of system is to bridge the gap between conceptual datamodeling techniques such as ERD and ORM, which often use classes and inheritance, and relational databases, which do not directly support them.

Relational Algebra. Relational algebras received little attention until the publication of E.F. Codd's relational model of data in 1970. Codd proposed such an algebra as a basis for database query languages. The first query language to be based on Codd's algebra was ISBL, and this pioneering work has been acclaimed by many authorities as having shown the way to make Codd's idea into a useful language. Business System 12 was a short-lived industry-strength relational DBMS that followed the ISBL example. In 1998 Chris Date and Hugh Darwen proposed a language called Tutorial D intended for use in teaching relational database theory, and its query language also draws on ISBL's ideas. Rel is an implementation of Tutorial D. Even the query language of SQL is loosely based on a relational algebra, though the operands in SQL (tables) are notexactly relations and several useful theorems about the relational algebra do not hold in the SQL counterpart (arguably to the detrim

Parentheses are classed as operators by the compiler, although their position is a bit unclear. They have a value in the sense that they assume the value of whatever expression is inside them. Parentheses are used for forcing a priority over operators. If an expression is written out in an ambiguous way, such as: a + b / 4 * 2 it is not clear what is meant by this. It could be interpreted in several ways: ((a + b) / 4) * 2 or (a + b)/ (4 * 2) or a + (b/4) * 2

Data models are a collection of conceptual tools for describing data, data relationships, data semantics and data constraints. There are three different groups : (i) Object-Based Logical Models. (ii) Record-Based Logical Models. (iii) Physical Data Models. We'll look at them in more detail now : (i) Object-Based Logical Models : Describe data at the conceptual and view levels. Provide fairly flexible structuring capabilities. Allow one to specify data constraints explicitly. Over 30 such models, including : a) Entity-Relationship Model b) Object-Oriented Model c) Binary Model d) Semantic Data Model e) Info Logical Model f) Functional Data Model

Data Abstraction The major purpose of a database system is to provide users with an abstract view of the system. The system hides certain details of how data is stored, created and maintained. Complexity should be hidden from the database users, which is known as Data Abstraction.  Levels of Abstraction : A common concept in computer science is levels (or less commonly layers) of abstraction, where in each level represents a different model of the same information and processes, but uses a system of expression involving a unique set of objects and compositions that are applicable only to a particular domain. Each relatively abstract, a "higher" level builds on a relatively concrete, "lower" level, which tends to provide an increasingly "granular" representation. For example, gates build on electronic circuits, binary on gates, machine language on binary, programming language on machine language, applications and operating systems on programm

What is Data and Information Data are plain facts. The word "data" is plural for "datum." When data are processed, organized, structured or presented in a given context so as to make them useful, they are called Information. It is not enough to have data . Data themselves are fairly useless, but when these data are interpreted and processed to determine its true meaning, they becomes useful and can be named as Information. Defining Database Definitions of Database : An organized body of related information. In computing, a database can be defined as a structured collection of records or data that is stored in a computer so that a program can consult it to answer queries. The records retrieved in answer to queries become information that can be used to make decisions. An organized collection of records presented in a standardized format searched by computers. A collection of data organized for rapid search and retrieval by a computer.

Q.1. What is an Instruction? Ans.: An instruction is a command given to the computer to perform a specified operation on given data. Each instruction consists of 2 parts: an opcode and an operand. The first part of an instruction, which specifies the operation, to be performed is known as opcode. The second part of an instruction called operand is the data on which computer perform the specified operation. As a computer understands instructions only in the form of 0 & 1, instruction and data are fed into the computer is a binary form. They are written in binary codes known as machine codes. For the convenience of this user the codes can be written in hexical form. Instructions are classified into the following three types according to their word length : (i) Single Byte Instruction (ii) Two Byte Instruction (iii) Three Byte Instruction

Q.1. Explain in detail about the concept of Addressing in the Memory. Ans.: Each instruction needs data on which it has to perform the specified operation. The data may be in the accumulator, GPR (general purpose registers) or in some specified memory location. The techniques of specifying the address of the data are known as addressing modes. The important addressing modes are as follows : (i) Direct Addressing (ii) Register Addressing (iii) Register Indirect Addressing (iv) Immediate Addressing (v) Relation Addressing (i) Direct Addressing : In this, the address of the data is specified within the instruction itself. Example of direct addressing is : (a) STA 2500H : store the contents of accumulator in the memory location 2500H. (ii) Register Addressing : In register addressing, the operands are located in the general purpose registers. In other words the contents of the register are the operands. Therefore only this name of the register is to be specified in the instru

Q.1. What are Logic Gates? Ans.: A digital computer uses binary number system for its operation. In the binary system there are only 2 digits, 0 and 1. The manipulation of binary information is done by logic circuit known as logic gates. The important logical operations which are frequently performed in the design of a digital system are: (1) AND (2) OR (3) NOT (4) NAND (5) NOR and EXCLUSIVE OR. An electronic circuit which performs a logical operation is called a logic gate. Q.2. Explain design of digital multiplexer. Ans.: A digital multiplexer has N inputs & only one output. By applying control signals any one input can be made, available at the output terminal. It‟s called data sector. Q.3. What are Combinational & Sequential Circuits? Ans.: There are two types of logic circuits, Combinational & Sequential. A combinational circuit is one in which the state of the O/P at any instant is entirely determined by the states of the I/P‟s at that time. Combination

Q.1. How can you classify Storage Devices? What are its different types elaborate? Ans.: Storage devices or secondary storage devices are used to store data and instruction permanently. They are used in computers to supplement the limited storage capacity of RAM. Floppy Disk : It‟s a circular disk coated with magnetic oxide and enclosed within square plastic cover (Jacket). It‟s available in different size, but the most commonly used floppy is 3½. Data up to 1.44 MB can be stored in it. Data is written as tiny magnetic spots on the dish surface creating new data or a disk surface eraser data previously stored at that location. Floppies are available in 2 sizes, 3.5 inch & 5.25 inch. The 3.5 inch size floppy is mostly used. The 5.25 inch floppy is kept in a flexible cover & it‟s not safe. It can store about 1.2 MB data. Hard Disk : Hard disks are made of aluminum or other metal alloys which are coated on both sides with magnetic material. Unlike floppy disks, hark disks

Q.5. Explain about LCD Monitors. Ans. : LCD stands for Liquid Crystal Display. Each pixel of an LCD typically consists of a layer of molecules aligned between 2 transparent electrodes, & 2 polarizing filters, the axis of transmission of which are perpendicular to each other. The surface of the electrodes that are in contact with the liquid crystal material are treated so as to align the liquid crystal molecules in a particular direction. Q.6. Explain about Video Controller. Ans.: A video display controller or VDC is an IC which is the main component in a video signal generator, a device responsible for the production of a TV video signal in a compulsory or games system. Q.7. Explain the different types of Printer: Ans.: Thermal Wax Printer : It uses wax coated ribbon & heated pairs. As the magenta, yellow & black ribbon passes in front of the print head, heated pins melt the wax on to the paper where it hardens. Thermal wax printers produce vibrant colors but