1. In MS-Dos 6.22, which part identifies the product uniquely

6.22

Explanation: MS stands for Microsoft, DOS is the name of operating system Disk Operating System, 6.22 is the version number that identifies the product.

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2. In Ms-Dos what command you will use to display system date?

Date command

Explanation: Ver command displays the version number of Dos. There is no command as Disk. Format command prepares a disk to be used with DOS. Thus Date is the command that lets you to display and/or change the system date.

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3. While working with Ms-Dos which command transfers a specific file from one disk to another?

Copy

For a specific file to copy from one disk to another disk, Copy command should be used. Diskcopy copies whole disk into new disk. Time command is to display system time and Rename command just changes the name of a file.

4. If you don’t know the current time, which command will you use to display

Time

Explanation: Time command displays and allows you to change system time. TIME only displays the system time and TIME is used to set new time as system time.

5. Which command divides the surface of the blank disk into sectors and assign a unique address to each one

Format

Explanation: Ver is used to display the version number of DOS in use. Fat command does not exist and Chkdsk is to check disk errors and fix it. Thus dividing surface into sectors is done by Format command.

6. Each time you turn on your computer, it will check on the control file

command.com, io.sys, msdos.sys

Explanation: command.com, io.sys and msdos.sys are the essential system files of MS-Dos. Loading these files from disk into memory is known as booting. Booting is the process of preparing your computer to work.

7. If you need to duplicate the entire disk, which command will you use?

Diskcopy

Explanation: Diskcopy is used to perform track-by-track copy of a disk into another. Copy command copies selected files; chkdsk and format commands are not for copying purpose.

8. Which of the following extensions suggest that the file is a backup copy

Bak

Explanation: Bak extension is commonly used to store backup copies of files so that it can be restored later when original file is corrupted or deleted. Bas extension indicates the file is a BASIC program source file, com is command file and txt is plain text file.

9. Which command lists the contents of current directory of a disk

Dir

Explanation: Dir command lists the directory of current location. It includes the files, subdirectories and some other system information. Tree command is used to list the directory structure in tree diagram; CD command to change directory and Copy command to copy a file into another.

10.Only filenames and extensions are to be displayed in wide format, which command you’ll use?

Dir/w

Explanation: Dir/w only displays the file names and extensions excluding file created date/time, file size. Second option dir a: will list the contents of A drive (floppy drive), third dir/s lists current directory and its subdirectories too, dir/b displays bare format, that means, it just makes a list of files, no more information.

PSC HSST Syllabus

COMPUTER SCIENCE /COMPUTER APPLICATION

1. Discrete Structures

Sets, Relations, Functions. Pigeonhole Principle, Inclusion-Exclusion principle, Equivalence and Partial Orderings. Elementary Counting Techniques. Computability : Models of computation - Finite Automata, Pushdown Automata, Non-determinism and NFA, DPDA and PDA s and Languages accepted by these structures. Grammars - types of grammars - type 0 , type I, type 2 and type 3. The relationship between types of grammars, Languages, Non-computability, Non-computable problems.

Groups : Finite fields and Error correcting / detecting codes. Propositional logic. Predicate logic. Well-formed formulae (WFF). Satisfiability and Tautology.

2. Computer Arithmetic

Logic families : TTL, ECL and C-MOS gates. Boolean algebra and Minimization of Boolean functions, Flip-flops- types, race condition and comparison, Design of combinational and sequential circuits.

Representation of Integers : Octal. Hex. Decimal and Binary 2's complement and 1's complement arithmetic. Floating point representation.

3 . Programming in C and C++

Programming in C : Elements of C - Tokens, identifiers, data types in C, Control constructs in C, Sequence, selection and iteration. Structured data types in C - arrays, structs, unions, strings and pointers.

Object-Oriented programming Concepts : Class - object, instantiation, Inheritance –polymorphism and overloading, aggregation, abstract classes, generalization as extension and restriction. Object oriented design. Multiple inheritance

C++ - programming : Elements of C++ - Tokens, Identifiers, Variables and constants. Data types, Operators. Control statements, Functions, parameter passing, Class and objects, Constructors and destructors, Overloading, Inheritance, Templates, Exception handling. 4. Relational Database Design and Query Languages E-R diagrams, Transformation of E-R models to relational design, Normalization - INF, 2NF, 3NF, BCNF and 4NF.

SQL : Data Definition Language ( DDL) , Data Manipulation Language (DML), Data Control

Language (CDL) Commands. Database objects like- Views, indexes, sequences, synonyms, data dictionary, Embedded SQL, QBE Query Processing and Optimisation, Centralised and Distributed Database, Security, Concurrency and Recovery in Centralised and Distributed Database Systems, Object Oriented Database Management Systems – Concepts, Composite objects, Integration with RDBMS applications.

5. Data Structures and Algorithms

Data, Information. Definition of data structure, Arrays, stacks, queues, linked lists, trees, graphs, priority queues and heaps.

File Structures : Fields, records and files. Sequential, direct, index-sequential and relative files. Hashing, inverted list and multi- lists, B-trees and B+ trees.

Graphs : Definition, walks, paths, connected graphs, regular and bipartite graphs, cycles and circuits. Tree and rooted tree, Spanning trees, Eccentricity of a vertex radius and diameter of a graph, Hamiltonian and Eulerian graphs. Planar graphs.

Sorting and Searching Algorithms, Analysis of Algorithms, Interpolation and Binary Search. Asymptotic notations - big oh. omega and theta. Average case analysis of simple programs like finding of a maximum of n elements. Recursion. Quick sort.

Design of Algorithms (Divide and Conquer. Greedy method. Dynamic programming. Back tracking. Branch and Bound).

6. Data Communication and Computer Networks

Data Communication : Analog and Digital transmission. Asynchronous and Synchronous transmission. Transmission media. Multiplexing and Concentration, Switching techniques.

Polling. Channel capacity. Transmission media - twisted pair, coaxial cables, fibre-optic cables, wireless transmission- radio, microwave and infrared waves. Light wave transmission. Telephones - local loop, trunks, multiplexing, switching, narrowband ISDN, broadband ISDN. ATM, High speed LANs. Cellular Radio, Communication satellitesgeosynchronous and low-orbit. Reference Models : The OSI model, TCP/I P model.

Topologies, Networking Devices. Protocols for - ( i) Data link layer (ii) Network layer, and (iii) Transport layer, TCP/I P protocols, Networks security, Network administration.

Local Area Networks (LAN), Metropolitan Area Networks (MAN), Wide Area Networks (WAN). Wireless Networks, Inter Networks.

Internetworking : Switch/Hub. Bridge. Router. Gateways. Concentrated virtual circuits. Tunnelling, Fragmentation. Firewalls.Routing : Virtual circuits and datagrams. Routing Algorithms. Congestion control. Network Security : Cryptography - public key, secret key, Domain Name System (DNS) – Electronic Mail and World Wide Web {WWW). The DNS, Resource Records. Name servers. E-mail architecture and E-mail Servers.

7. System software and Compilers.

Assembly language fundamentals (8085 and 8088 based assembly language programming). Assemblers - 2-pass and single-pass. Macros and macro processors. Loading, linking, relocation, program relocatability. Linkage editing.

Text editors, Programming Environments. Debuggers and program generators.Compilation and Interpretation. Bootstrapping. Phases of compilation. Lexical analysis. LEX. Context free grammars. Parsing and parse trees. Representation of parse trees and rightmost and leftmost derivations, Bottom up parsers - shift-reduce. operator precedence and LR. YACC.

Top down parsers - left recursion and its removal. Recursive descent parser. Predictive parser.

Intermediate codes - Quadruples, Triples. Indirect Triples. Intermediate code generation, Code generation, Code optimization.’

8. Operating Systems

Main functions of operating systems. Multiprogramming, multiprocessing and multitasking.

Memory management ; Virtual memory, paging, fragmentation.

Concurrent processing : Mutual exclusion. Critical regions, lock and unlock.

Scheduling : CPU scheduling. I /O Scheduling. Resource scheduling. Deadlock and scheduling

algorithms. Banker's algorithm for deadlock handling.

The Unix system : File system, process management. Bourne shell, shell variables, command line programming.

Systems Calls : Creat, open, close, read, write. Iseek, link, unlink, stat, fstat, umask, chmod, exec, fork, wait, system.

M 9. Software Engineering

System Development Life Cycle (SDLC) : Steps, Water fall model. Prototypes, Spiral model.

Software Metrics ; Software Project Management.

Software Design : System design. detailed design. function oriented design, object-oriented design, user interface design. Design level metrics.

Coding and Testing : Testing level metrics. Software quality and reliability. Clean room approach, software engineering

10. Computer Graphics

Display systems. Input devices, 2D Geometry - .Algorithms for drawing primitives, clipping and windowing, windows, view ports, Graphic operations for transformations , 3D Graphics. Animation, Graphics standard. Applications.

Storage Devices, Input Tools. Authoring Tools, Application, Files.

11. Programming Language Theory

Programming language concepts, paradigms, models.

Data. Data types, Operators, Expressions. Assignment. Flow of Control - Control structures, I/O structures. I/O statements, User-Defined and built- in functions. Parameter passing.

Principles, classes, inheritance, class hierarchies, polymorphism, dynamic binding, reference semantics and their implementation.

Principles, functions, lists, types and polymorphism, higher order functions, lazy evaluation, equations and pattern matching.

Principles, horn clauses and their execution, logical variables, relations, data structures, controlling the search order, program development in Prolog, implementation of Prolog, example programs in

Prolog.

12. Current Trends and Technologies

The topics of current interest in Computer Science and Computer Applications shall be covered. The experts shall use their judgement from time to time to include the topics of popular interest which are expected to be known by an ardent follower of the field. Currently, they include :

Parallel computing

Parallel virtual Machine (PVM) and message passing interface (MPI) libraries and calls. Advanced

architectures. Today's fastest computersMobile Computing

Mobile connectivity - Cells. Framework, wireless delivery technology and switching methods, mobile

information access devices, mobile data internetworking standards, cellular data communication

protocols, mobile computing applications. Mobile databases - protocols, scope, tools and technology.

E-Technologies

Electronic Commerce : Framework, Media convergence of Applications, Consumer Applications, Organisation applications.

Electronic Payment Systems : Digital Token, Smart Cards, Credit Cards. Risks in Electronic Payment System, Designing Electronic Payment Systems.

Electronic Data Interchange (EDI) : Concepts, Applications, (Legal, Security and Privacy) issues.

EDI and Electronic Commerce. Standardisation and EDI. EDI Software Implementation. EDI

Envelope for Message Transport, internet-based EDI.

Data Warehousing : Data Warehouse environment, architecture of a data warehouse methodology, analysis, design, construction and administration.

Data Mining : Extracting models and patterns from large databases, data mining techniques, classification, regression, clustering, summarization, dependency modelling, link analysis, sequencing analysis, mining scientific and business data.

Principles of parallelism, co routines, communication and execution, Parallel Virtual Machine (PVM) and Message Passing Interface (MPI) routines and calls. Parallel programs in PVM paradigm as well as MPl paradigm for simple problems like matrix multiplication.