What is Gibb's Phase rule ?

The celebrated phase rule given by J. Willard Gibbs provides a general and useful relationship between the number of phases P, number of component C and the number of degree of freedom F, which must be specified in order to characterize a heterogenous system. According to Gibbs phase rule, a heterogenous system is not affected by gravity or by electrical and magnetic forces.

The Gibbs phase rule is stated as:

If a heterogenous system in equilibrium between any number of phases is influenced by temperature pressure and concentration only and not by gravity or electrical or magnetic forces or by surface action then the sum of number of phases P and degree of freedom F is greater than number of components C by two.

Large and heavy castings are made by ?

a) green sand moulding.

(b) dry sand moulding.

(c) pressure moulding

(d) machine moulding

What is an isomorphous system ? Give an example.

The term isomorphous system is related to phase diagram. Isomorphicity means having same crystal structure or complete solubility for all compositions. The copper nickel system is an example of isomorphous system.

What is peritectic reaction ?

A reaction where in, upon cooling a solid and a liquid phase transform isothermally and reversibly to a solid phase having different composition is called a peritectic reaction.

Define Burger's Vector.

Burger vector is defined as plastic displacement produced by the dislocation. It describes both magnitude and direction of slip.

State the Griffith criterion for crack propagation in brittle solid.

Brittle fracture is the failure of a material without apparent plastic deformation. If the broken pieces after a brittle fracture are fitted together, lies the original shape and dimensions of specimen are restored.

Griffith has postulated a criterion for the propagation of pre-existing crack in brittle material (glass). Griffith postulated that brittle fracture occured when the energy release rate during crack growth exceeded the rate that energy was required.

What do you mean by ‘Biosphere Cycle’?

Biosphere means sphere of life.
The idea of biosphere was suggested by Austrian Geologist Edward Suess nearly a century ago. At that time it was not so important concept. Today, however, the biosphere has become the most important problem faced by man. The basic function of biosphere is that it supports life. It is esteemed that biosphere contains more than three hundred and fifty thousand species of plants and eleven million animal species including man. The biosphere supplies the essential requirements for all those species such as plants, animal and human beings namely light, heat, water, food and living space etc.

Biosphere Cycle :- Maintenance of the biosphere is possible through constant recycling of materials betweenthe biotic (living) and abiotic (non-living) components. These cycles are given below:-

(i) Hydrological Cycle :- The path of water through environment is hydrological cycle.

(ii) Carbon Cycle:- Carbon serves two purposes in the environment
1. It is structural component of organic molecules and
2. The energy holding chemicals bonds it forms for energy storage.

(iii) Nitrogen Cycle:- Organisms cannot exist without amino acids, peptides, nucleic acids and protein all of which are organic molecules containing nitrogen.

(iv) The Phosphorous Cycle:- Minerals become available to organisms after they are released from rocks. Phosphorous cycle is one of the mineral cycle begins when phosphorous compounds are leached from rocks and minerals over long period of time.

(v) The Sulphur Cycle:- Sulphur plays a vital role in organisms, especially as a minor but essential components of proteins. Sulphur compounds are important determinants of the acidity of rainfall, surface water and soil.

(vi) Oxygen Cycle:- Oxygen is the main source of respiratory gas for all terrestrial organisms.

What do you understand by the term 'Global Warming'?

Global Warming: Rise in the temperature of globe (earth) is called global warming. The average global temperature reached 15.39 degree Celsius in 1995 breaking the previous records. Coming of every year will be the hottest. For example, Visakhapatnam recorded a day temperature of 39.6 degree, the highest in the last 100 years on July, 1977. More or less, same is the case with almost all coastel cities of Andhra Pradesh. Global Warming is being felt due to the specific characteristics of the greenhouse gases (GHE). Greenhouse gases are three:
(i) Carbon dioxide CO2
(ii) Water vapour H2O
(iii) Ozone O3

Out of these three gases, only carbon dioxide contributes largely to the greenhouse effect in the earth's atmosphere, because carbon dioxide is much more uniformly distributed in atmosphere. The major supplies of carbon dioxide gas to the atmosphere are:
(i) Eruption of volcanoes
(ii) Respiration of living organisms
(iii) Decay of dead organisms
(iv) Burning of fossil fuels
(v) Cultivation of land.
Contribution to global warming is 24% by industrial processes; 14% by deforestation; 13% by agriculture and 49% by energy use.

What factors contribute to ecological imbalance?

Causes of Eco-Imbalance: The reasons which cause ecological imbalance are given below: If beyond 30% of forest land area is resorted to tree-felling than eco-balance is disturbed. About 95% of the land in the arid and semi-arid regions of the world area in the process of desertification. Desertification means changing land into desert area.

1. Deforestation and Desertification.
2. Aerobic process accumulation enhancing need of BOD, COD and DO emanating from sewage and other wastes.
3. Industrial effluents and Agricultural discharges.
4. Automobiles, more than 40 lakhs surface transport moves on the roads of Delhi only.
5. Industrial chimney Thermal Power Stations, emission of flyash and dust from stone crushers.
6. Population and Gulf-war.

What do you mean by 'Scientific Management'?

Scientific management means the application of scientific methods of study analysis to the problems of management. It is a systematic and thoughtful approach to the job of management as compared to the rule of thumb or trial and error. It is concerned with the scientific bent of mind and is more than merely a set of techniques for improving efficiency.

Scientific management was developed and introduced by F.W. Taylor in 1910.

'Technology adoptation depends upon a number of factors.' Comment.

Factors needing attention of Technology Adoptation:

(a) The technology selected for transfer should be appropriate and the purpose for which it is intended to be transferred.

(b) Status of development is another important issue with regard to transfer of technology.

(c) The technology selected for use should not be so much expensive. It should be competitive otherwise it will not be commercially accepted.

(d) The technology to be transferred should be provided with the backup services. The user of technology should be provided with the services like planning, selection of equipment, layout of the factory, erection, commissioning and trouble shooting during operation.

(e) Evaluation of technology is important before it is tranferred from lab to field or industry. This evaluation has to be done to find out whether the claims made are justified by actual facts. If they are not then that very technology should be dropped.

(f) Transferring agency may be like NRDC is essential because technology transfer is not only a matter of technology but also a matter of commerce and law.

(g) Provision of guarantees with regard to performance of the technology on commercial-scale is equally important.

What is multiplexing? Distinguish between frequency division and time division multiplexing.

Multiplexing is that the method of permitting multiple signals from totally different sources to share common channel. that's one channel is employed by totally different signal sources to send their signals.

Some types of multiplexing are:

(a) TDM (Time Division Multiplexing
(b) FDM (Frequency Division Multiplexing)
(c) WDM (Wavelength Division Multiplexing)
(d) CDM (Code Division Multiplexing

TDM: In TDM signals area unit separated in time domain. Signals from varied sources area unit allowed to flow through the common line one at a time for fastened time. Suppose there area unit four signal sources, then every signal supply are allowed to use line for a amount t. Once all signal sources transmit for amount t, the primary one once more get likelihood so on.

FDM: In FDM signals area unit separated in frequency domain. Signal from every supply is modulated to totally different frequency in order that the frequency spectrum once modulation won't overlap. At receiving finish, signals area unit demodulated. (i.e. translated back to original frequency).

What is Modem? Describe its role in Data Communication.

Modem is the short form of Modulator-Demodulator. It is a device through which computer send and receive data from telephone lines. 

Modem as well as Ethernet Card are essential to provide Data One Broadband Connection?

Computer generates discrete data. They cannot be send through telephone lines which are designed for carrying analog signals. Modem accepts the data from computer and convert into analog signals using modulation procedure called ASK (Amplitude Shift Keying), PSK (Phase Shift Keying) or FSK (Frequency Shift Keying) or a variant of these modulation methods. These analog signals are send over telephone lines. The signals that come through telephone lines are reconverted back to binary (discrete) form by demodulator part of the modem. A modem can accept as well as transmit data serially simultaneously. Normal data transfer rates are 56 kbps, 144 kbps or 288 kbps.

What is Data Link Layer?

What are different types of file organisations used in contemporary file systems in modern-day operating system? Explain with examples.

File organization defines however records in an exceedingly file area unit associated with each other. totally different file organizations area unit designed to optimize performance for one or each file access ways. There area unit many common file organizations. They are:

(a) SEQUENTIAL FILE: Here records area unit organized in an exceedingly sequence adjacent to 1 another. Records area unit accessed consecutive. To browse a file record, the records ranging from 1st record forwards is browse (or from current record onward is read) till the required record is found.

(b) RELATIVE OR DIRECT FILE: Here record occurrences area unit physically situated at Associate in Nursing address that's calculated from its primary key field. The calculation of the address from the key field is termed hashing. therefore record occurrences area unit scattered on the memory device rather than being organized next to 1 another. Records are often retrieved chop-chop applying the hashing formula to the first key field of the required record. Relative files area unit excellent for things wherever fast access to tiny low proportion of records in an exceedingly file area unit required by programs.


INDEXED FILES: Here records area unit pointed to by indexes. the benefits of Associate in Nursing index is that it's comparatively tiny and straightforward to update. At a most, the file can have one index per primary key. This index purpose to the precise location wherever knowledge (record) is hold on. If not maintained properly, indexes will become corrupt and need reconstruction.

INDEXED SEQUENTIAL FILE: this can be a special variation on the indexed file conception. Records area unit physically organized in sequence to permit consecutive access, in contiguous locations or employing a joined list or each. These file conjointly contain Associate in Nursing index of record keys and their physical addresses that may be accustomed give semi direct access to records at intervals the consecutive file. every program determines however it wish to access the records, whether or not consecutive or via the index.

What is meant by memory hierarchy? Is it possible to have a computer system without any secondary storage? Explain your answer.

Memory Hierarchy is the way in which different type of memory is arranged according to size, cost and speed.

What are the necessary layers of memory hierarchy that helps to create the virtual memory? 


Computer systems can be constructed without secondary storage. There are many computer systems without secondary storage.

An EPROM can be used to used to do initial activities (like booting) when powered ON. Programs can be entered into RAM by typing in and can be executed. Only problem is backup of program and data is not possible normally. In many computer systems EPROM'S are used to as secondary memory.

What is EPROM? How is it different from PROM?

What is meant by Strategic Information System? Explain briefly where such a system is used and the important components of such a system.

Strategic Information Systems are special types of information system which support the change of goal, operation, products, services or environmental relationships of organization. Due to strategic information systems, a competitive edge over the other organizations is gained. Computers play an important role in implementing strategic information system. Some places where the system is used are health care, distribution of products, researching of transport operations, e Governance system for policy management.


What do you mean by Office Automation?
 

Important components of strategic information system are:-

(a) Domain resources like survey forms publicity leaflets, order-forms, service forms etc.

(b) Technological resources like computers, fax machines, telephones, presentation equipment's and related software.

(c) Human resource like managers, trained personal, brokers etc.

A management information system is an example of a system program?
 

What are the function of an Operating System? Differentiate between multiprogramming, multiprocessing. Which OS are single user and multiusers? Give example of each.

An Operating System has four major functions. They are:-

(a) Memory management
(b) Processor management
(c) I/O management
(d) Information management

What is Multitasking OS?

MULTI-PROGRAMMING:- It is the process by which CPU executes programs that reside in memory on time sharing basis. In a multi programming environment, multiple programs are allowed to reside in memory at the same time. Processor executes one program for a short time and then next one is executed for short time and so on until all programs are executed for a short interval. Then it again take up the first one and execute for another short interval and then next one and so on. This process is repeated until programs are completely executed. If a program is completed it is removed from memory and next program that is ready is loaded into the memory.

Unix is a multiuser operating system?
 

MULTIPROCESSING:- In a multiprocessing system there will be more than one processor. Since there are more than one processor, more than one activity can be performed at the same time.

Operating System acts as a resource manager for any computer system?


An example of single user operating system is DOS. An example of multi-user operating system is UNIX.

Differentiate between Compilers, assembler and translator. Explain their working and the situations where each is useful.

COMPILERS: They're computer code that interprets program written in high level language to machine language. Compilers are advanced programs.

How is an interpreter different from a compiler?

What is meant by Compiling a program?

What is Cross Compiler? 

What are different passes of a compiler? 

Explain the stages of compilation for a C Compiler?
 
ASSEMBLERS They're computer code that interprets programs written in programming language to machine language.

An assembler for Pentium is mandatory to support C++

TRANSLATOR: Translators are computer code than will convert programs written in one language to a different language. Compilers, interpreters, assemblers etc. are example of translators.

Compilers use several phases for conversion. They are:-

LEXICAL ANALYSIS: Checking for invalid symbols in program.

SYNTAX ANALYSIS: Checking validity of syntax used.


CODE GENERATION: Convert every statement to equivalent machine language.

CODE OPTIMIZATION: Generated code is analyzed for redundancy and best code is generated.

Assemblers typically uses 2 or 3 phases (passes) for changing programming language program to machine language program. within the initial pass, macro calls are swollen. within the second pass forward references are resolved and within the third pass actual machine language generation is finished.


Once computer code is developed victimization high level languages, compilers are essential for translation. Similarly, assemblers are needed for translation in places wherever programs are developed in programming language.

What is Client Server Technology? What are their advantages and disadvantages? Discuss them briefly.

Client Server model consist of a set of clients and a set of servers. Servers are a group of cooperating processes that offer services to users. Users are called Clients. Client and server machines are connected in a computer network. The client sends a request and gets an answer from the server.

Client request contain request for some service (like reading a file etc) The server does the work and returns the data requested or an error code indicating why the work could not be performed. No connection has to be established before use or torn down afterwards the reply message serves as the acknowledgement to the request.

Prime advantage of Client Server Model is its simplicity. It is simple because no connection establishment and disconnection is required. Client sends request and gets its reply.

Another advantage is efficiency. The protocol stack used to implement Client Server Model is simple.

Client Server model allows resource sharing between different users.

Another advantage is high reliability. By having alternate sources of supply of data reliability improves. If one server is down another server may be able to service the request. More and more clients can be easily added in a network. It also provide communication medium for widely separated people.

Disadvantages of Client Server Model are:-

1. Operating system that implements the Client Server model is complicated and costly.

2. It is network dependent. Fault in network, network saturation etc. can affect the performance of system.

3. Security: Easy access to data which can be measured.

What is Multitasking OS?  

What is a Program? 

What is Kernel?


What are the major forms of Stratification System?

Caste: Caste is real organized group of society. In caste social status of individual varies. Some are higher some are lower. There is no definite geographical location. Endogenous system of marriage prevails which means members of a particular case cannot marry outside the caste.

Class: Stratification (division) based on wealth and prestige is called class. A class is a group of individuals, who through common descent, similarity of occupation, wealth and education have come to have a similar mode of life, a similar stock of ideas, feelings attitude and behavior. The broad characteristics of class are-

(1) relation between lower and upper class
(2) superiority and inferiority
(3) social mobility from one class to another.

Differentiate between Folk ways and Mores.

(i) Folkways have wider character and scope compared to Mores.

(ii) Mores are more practical and effective in molding and training the tendencies of individuals than the folkways.

(iii) Conviction of right and wrong comes out of Mores and not Folkways.

(iv) Mores are very deeply rooted in society than Folkways.

(v) Mores play both positive and negative roles and Folkways play only positive roles.

What are the recent changes in the Caste System?

(i) Due to technological advancement caste system is broken and at work caste has not much effect on the workers.

(ii) By educational infrastructure development taken place in last two decades, it has become possible for every caste member to take admissions in institutions to enhance or get education effecting caste system badly.

(iii) Globalization has also effected caste system badly and now caste has no effect in cities.

(iv) Education is now possible to female child also and make marriage institution and easy task for female and his family members, as female has become now earning member and is easy for female to marry outside the caste system.

(v) Now a days caste is for backward people. 

What are the major forms of Stratification System? 


Definition of variable in C programming language:

A variable is named location of data. In other word we can variable is container of data. In real world you have used various type containers for specific purpose. For example you have used suitcase to store clothes, match box to store match sticks etc. In the same way variables of different data type is used to store different types of data. For example integer variables are used to store integers char variables is used to store characters etc. On the basis of how many data a variable will store, we can categorize the all c variable in three groups.
(a)Variables which can store only one data at time. Example: integer variables, char variables, pointer variables etc.
(b)Variables which can store more than one data of similar type at a time. Example: array variables
(c) Variables, which can store more than one value of dissimilar type at a time. Example: structure or union variables.

Properties of variable in c:
Every variable in c have three most fundamental attributes. They are:
1. Name
2. Value
3. Address

Name of a variable:
Every variable in c has its own name. A variable without any name is name is not possible in c. Most important properties of variables name are its unique names. Not two variables in c can have same name with same visibility.

What is array and why array in c? 

What is a key word and what are the restrictions of using them? 

C is a procedural programming language?


Explain the reason for cracking of brass

In addition to the changes in physical and chemical properties, internal stress, often of a very high intensity, may be left in the object after cold deformation.

Metals such as brass with internal stresses appearing after working is susceptible to inter-crystalline corrosion. If it is stored for a long period. This leads to disintegration or failure of the metal. This phenomenon is called season cracking, or more correctly stress corrosion cracking. Development of cracks is accelerated by reaction with corrosive medium and the cracks go round the grains, i.e. they inter-crystalline. This defect is overcome by annealing the brass at about 300 degree C.

How is martensite formed in steel?

Martensite is formed when specimen is quenched in water above the critical cooling rate from the authenticate region (i.e. above A3 temperature) to room temperature.

State the crystal structures of Cementite and martensite 


How do you determine the temperature for hot working of a metal?

The lower temperature limit of hot working is the lowest temperature at which the rate of re-crystallization eliminates strain hardening. This lower limit depends upon
(i) amount of deformation
(ii) time for which the metal is at that temperature

Thus lower temperature limit for hot working is decreased, for large deformation.

Most hot working operations are done in a number of steps. The working temperature of intermediate phases is kept much above the lower temperature limit. At this temperature, the amount of deformation is more, as well as the cost of working is lower. But at this temperature grain growth will be there. To have, finally the fine grain size structure, the working temperature in the last pass (or step) is lowered. This finishing temperature is usually above the minimum re-crystallization temperature.

Give two applications of nano materials?

(a) Next-generation computer chips.
(b) Kinetic energy penetrates with enhanced legality.

How does CPU execute program instructions?

What is array and why array in c?

An array is derived data type in c programming language which can store similar type of data in continuous memory location. Data may be primitive type (int, char, float, double…), address of union, structure, pointer, function or another array.

Example of array declaration:
int arr[5];
char arr[5];
float arr[5];
long double arr[5];
char * arr[5];
int (arr[])();
double ** arr[5];

Array is useful when:
(a) We have to store large number of data of similar type. If we have large number of similar kind of variable then it is very difficult to remember name of all variables and write the program.
(b)We want to store large number of data in continuous memory location. Array always stores data in continuous memory location.

Advantages of using array:
1. An array provides single name .So it easy to remember the name of all element of an array.
2. Array name gives base address of an array .So with the help increment operator we can visit one by one all the element of an array.
3. Array has many application data structure.

Definition of variable in C programming language 

Is a two dimensional array passed as a value or reference argument to a function?

Explain the following statement of C: int (*x) [20]


what is System Concept?

A system may be defined as a group of inter-related parts or elements designed to achieve a particular goal.

An engineering system usually utilities the human efforts, materials, machine and finance to achieve desired objectives.

A manufacturing system to be a collection of integrated equipment and human resources, whose function is to perform one or more processing and/or assembly operations on a starting raw material, part or set of part.

Automated Guided Vehicles (AGVS)

AGVS is a material handling system that uses independently operated, self propelled vehicles, guided along defined path ways. The vehicles are powered by on board batteries that allow many hours of operation (8-16 hrs is typical) between recharging.

The distinguishing feature of a AGVS compared to rail guided vehicle system and most conveyor system, is that the path way are UN-obtrusive. AGVS is appropriate where different material are moved from various load points to various unload points. It is used in batch production and mixed model production system.

Types of AGVS
1. Driven less train
2. Pallet trucks
3. Unit load carriers

AGVS system are used in
1. Assembly line application
2. Storage and distribution
3. Flexible manufacturing system
4. Office mail delivery
5. Hospital material management

Explain the meaning of 'Work'. 'Work' is a central focus in 'Society'. Comment.

Any positive activity directed towards productivity and output is called work. We always worship work and say work is worshiped and not worship is work. It is centrally focused in the society is a correct statement. Without work nothing can be achieved. Work at home is attended mostly by womenfolk and work at site and offices are handled by man. Work leads to development of any society and without work society shall fail. If all the people living in the society attend to the work assigned then everybody shall be happy and wealthy. By doing work we are able to make money and with the help of money we buy all the necessary and luxury items required for sustaining the life. By doing work regularly in any profession or job we satisfy ourselves and justify our living on the planet earth. Man without work is devil. All devils engage in evils. Evil retard growth. Hence work is essential.

Discuss the criteria for the assessment of appropriate technology.

Differentiate Between Culture and Civilization.

What is Design for Recyclability?

Designing so that reusable materials and long-lived components can be recovered, with reduced the cost of new component. Recently, a trend of environmentally conscious products along-with the rapid implementation of worldwide environmental legislation have put the responsibility for the end of life disposal of products on to the manufacturer. Manufacturers must now implement rules during the design that enforces design for recyclability. By designing and considering it, manufacturer are gaining an edge over slow reacting competitors.

Difference between 'Science' and 'Technology'

By science we mean, a systematic study where facts are observed and classified for a particular phenomena. Science formulates quantitative laws and verify them for application through instruments and apparatus.

Technology means application of mind for learning methods and techniques of completing a given job or work efficiently. Technology applies science and scientific facts and achieve the benefits for mankind. Use of technology extend the ability of man beyond natural capacity of his mind. But all these depends on scientific laws and researches by scientists in labs and verification made by them. So science and technology are incomplete without each other.

What is Planning? How it can be made more effective?

Is Sociology a Science? Discuss.

How many independant slip systems are required for plastic deformation in polycrystalline materials ?

No. of slip systems are required for plastic deformation in poly-crystalline materials = 2 Nos.

Write down the Slip Plane and Slip Direction?

State the Griffith criterion for crack propagation in brittle solid.

 

What is Planning? How it can be made more effective?

Role of Planning in Development

Planning is a method of making better decisions for the future. It is an important component of development activities. The idea of planning was inherited from Russia. This country make long term development plans varying from 15 to 20 years. To plan is to act according to decision. All works with planning if well defined, goals and objectives are achieved whether it is an individual firm, professional body, governments, corporate sector or any other unit involved in economic growth, inter-sectional coordination, social welfare and social relations. In INDIA, the idea of planning has been identified more with extensive government control over the economy (country). Since 1951 successive 5 year plans have been prepared by the Planning Commission. These are development plans. So far we have completed nine five year plans, and are about to complete 10th FYP. Each plan lays down broad targets, energy and transport, industry, health and family welfare, science and technology etc. Ours is a mixed economy in which a plan acts as a mean of coordinating actions within the public sector and between the public and the private sectors. Even plan requires approval of the National Development Council which includes Chief Ministers of all the States. Planning in our country is highly centralized. Socioeconomic reformers suggest that we should choose between planning from above and planning from below.

The processes of production and consumption takes places in a Social Change.

Social Change comes with the change in the tools of production. Tools of production refer to equipment and machines used in producing different types of material and non-material goods.
Social Change means observable difference perceived (seen) over a period of time. Technology and use of tools bring major social change. The more advanced tools, the more rapid social change will be brought. Industrial revolution in U.K. and green revolution in India are considered two major process which have brought sufficient changes in the field of agriculture and industry and which has brought sufficient social change. Introduction of cooking gas, use of vacuum cleaner, water pumps, inverters and desert coolers have created social change in society.

What is Spooling ?

Spooling (Simultaneous Peripheral Operation On Line): This is an I/O management technique in which dedicated devices are managed in efficient way. Here all output activities that is to be done (like printing etc.) is saved in memory until the process (program that is being executed) is completed. The saved output is then printed at high speed rather than intermittently spread over the entire duration of process.

State the crystal structures of Cementite and martensite.

Iron Carbide or Cementite (Fe3C): It is chemical compound of iron and carbon of composition Fe3C. It is of orthorhombic structure. Its unit cell has 12 iron atoms and 4 carbon atoms. It has carbon content of 6.67%. Its melting point is approximately 1550 degree C Cementite is magnetic upto 210 degree C. It is non-ductile and brittle, interstitial compound of low tensile strength but high compressive strength.
It iron-iron carbide diagram, the melting point of iron is shown by point (1538 degree C) and melting point of cementite is (1500 degree C). The structure changes from bcc ferrite to fcc austenite at point G (912 degree C) and from y-fcc to a-fcc at point N (1394 degree C).
When cooling rate is increased above critical value i.e. upon water quenching, the time is too less for carbon to diffuse out of solution. Therefore the fcc structure does not change to bcc structure while carbon is trapped in solution. The resulting structure is body center tetragonal which is called martensite. It is super saturated solid solution and non-cubic structure. The two dimensions of body center tetragonal unit cell are equal while the third side is slightly expandd because of trapped carbon. Because carbon is present in the lattice, slip does not occur easily. That is why, martensite is hard, strong and brittle. It has needle like structure.

What are the key features of a LAN ?

Key features of LAN are:-

1. Networking limited to a small geographical area (less than 1km radius)

2. High speed data transfer.

3. Data error rate is very less since data is transferred to limited distance.

4. Managing local area networks is easy as only a single technology and symmetrical topology is used.

5. Only limited number of computers connected in a LAN network.

6. Types of data supported is tailored to the application.

Write the scientific names of PET and Melamine.

PET (Polyethylene terephthalate)
Melamine (Melamine-formaldehyde)

Name two soft magnetic materials.

(i) Soft iron silicon alloy
(ii) Soft iron nickel alloys

Specify the key differences between an impact printer and a non-impact printer OR a graphics printer and a character printer with relevant examples.

Impact printers press formed character faces against an inked ribbon on to the paper. A line printer is an example of an impact device with the type faces mounted on bands, chains, drums or wheels.

Non impact printers use laser techniques, inkjet sprays, xerographic processes or electrostatic or electro-thermal methods to get images on the paper.

Character impact printers often have a dot matrix print head containing a rectangular array of protruding wire pins with the number of pins depending on the quality of the printer. Individual characters or graphics patterns are obtained by retracting certain pins so that the retracting pins from the pattern to be printed. Graphic applications use generally non impact printers with different color toners.

Distinguish between Information System and a File System.

Information system consists of collection of information which are stored in memory. This include library segments, data segments, system segment etc.

Modules of the operating system dealing with the management of information is called File Systems. File System is intended to provide convenient management of information. So the programmer is freed from problems related to the allocation of space for his information as well as other problems such as storage format and I/O addressing.

Specify the various processing steps that are needed in exact sequence when any existing high level source program lika a C program file stored on Disc is to be executed on a PC. Clearly mention the various system Software modulus clearly high lighting their roles.

When we want to execute a high level source program in disk, the following steps are performed:-

(i) Load the program from hard disk to primary memory.

(ii) Compiler is used to translate the program. Compiler generates an executable file and store it in disk.

(iii) Loader is then activated to load the program into primary memory at appropriate locations.

(iv) Linker is then activated to link various modules of the program.

(v) Program control is transferred to appropriate location within the program so that execution can start.

What are the distinctive features of a Relational Data Base? Specify with some examples.

A Relational Data Base usually consists of many relations (table of values in which each row represent collection of related data values). A row in the table is called tuple. A column header is called an attribute. Data is stored in relations and retrieved according to the needs of user using query language (like SQL).

What are the various types of resource management modules (if any) that area present in any operating system? Specify their functionality in brief.

There are four major resources that are controlled by the operating system are:-

(a) Memory
(b) Processors
(c) Devices
(d) Information

Memory management module organizes the memory allocation and effective utilization of memory. It involves paging mechanism, segmentation etc.

Processor management involves effective utilization of processor like multi-programming. Processor management module keep track of status of each process and select the processes from a ready list to be run. It suspend running process when it runs out of allotted time. It also co-ordinate inter process communication. The component of the operating system that perform these tasks is called traffic controller.

Device management modules helps to use the devices in most efficient manner. Devices can be dedicated or shared access type. Certain devices like printer, magnetic tapes can be used one at a time manner. They can be allocated in dedicated manner or by Spooling, I/O management modules decide this. Magnetic drum disks etc. can be concurrently used by more than one job. In such cases if two or more jobs wish to access the same device simultaneously. Operating system must act as I/O traffic controller.

Modules of operating system dealing with management of information are often called the file system. It is concerned with the logical organisation of information. The file system deals with collections of unstructured and uninterpreted information at the operating systems level.

What are the key characteristics of a Network Protocol? Why Protocol are needed?

Protocol is a set of rules that communicating entities must follow for orderly exchange of data.

Implementation of computer network is a complex task. Hence it is divided into number of layers. Suppose a layer n at source wants to communicate to a layer n at the destination, then there should be a standard mechanism so that both layers at same level should be able to talk to each other. The rules and conventions required for the communication are called as protocols. In general layered protocols must meet the following goals.

(a) Provide a logical decomposition of a complex network into smaller, more under-standable parts or layers.

(b) Provide symmetry in functions at each node in the network. Each layer performs the same functions as its counterpart in other nodes of the network.

(c) Provide a means to predict and control any changes made to network logic.

(d) Provide a standard language to clarify communication between network designers, manager and users.

What is Electronic Data Interchange (EDI)? Explain its salient features.

EDI is an Internet service provided for making commerce electronically known as e-commerce. It allows computer exchange of standard items like invoice, bills, orders, bank transfer etc. Features of EDI are:-

1. It reduces inventory costs

2. It displays information globally

3. Connects customer and seller at long distances

4. It automates the transaction process

5. It saves time, cost and energy

6. It transmits structured messages and provides strategic benefits.

What is meant by Information Systems? How are they different from a File System?

An Information System is a set of elements each of which is capable of carrying out certain information processing. All the elements performing the task of Information processing together for achieving a desired objective constitute an Information System. A personal computer is an example of Information System. An Information System in general consist of the following units

(1) Logical organizational units
(2) Computer hardware and software
(3) Information related personnels

File System is concerned with the logical organization of Information. File System deals with collection of unstructured and uninterpreted information. Each separately identified collection and information is called the File. A database management system is a file system that performs some structuring of information. We can functionally divide the file system into seven logical phases. They are:-

(a) Accessing methods
(b) Logical file system
(c) Basic file system
(d) File organisation strategy
(e) Allocation system strategy
(f) Device strategy
(g) I/O control system

A Programmer makes a request to read a file. He use a symbolic name. The logical file system accepts the symbolic name and finds the corresponding numeric file identifier. The basic file system takes the numeric file identifier and obtains a file descriptor. The file organisation strategy module uses the file descriptor to determine the physical address. The device strategy module produces the physical I/O commands to access the information (from where it is stored). I/O control system schedules the execution of the physical file commands.

Difference between Ink-Jet and Laser Printers with reference to their working.

Ink Jet Printers spray cyan, magenta, yellow and sometimes black ink onto a paper. Ink Jet are mounted on a head in a printer like mechanism. The print head moves across the page to draw one scan line, return while paper advances by one interscan line spacing and then draws next scan line. All colours are deposited simultaneously.

Laser Printers scan a laser beam across a positively charged rotating drum coated with selenium. The areas hit by the laser beam lose their charge and the positive charge remains only where the copy is to be black. A negatively charged powdered toner adheres to the positive areas of the drum and is then transferred to blank paper to form the copy. In Colour Printers this process is repeated three times once for each primary colour.

Distinguish between a text file and a binary file.

In a text file, bytes are treated as characters. Binary data is grouped into bytes and bytes are interpreted as characters based on some standard codes like ASCII or EBCDIC.

In a binary file the sequence of bits stored in file are not interpreted as characters. They may be executable code after compilation of program or graphics data or multimedia data. These bits are interpreted by the target user according to their specific purpose of creation.

What is DBMS? What are different types of DBMS? Compare these different types of DBMS?

A database management system is a collection of programs that enables users to create and maintain a database. It is a general purpose software system that facilitates the process of defining, constructing and manipulating databases for various applications.

There are three models available to organise the data sets in the form of databases. They are:

(a) Relational Model: In this model data elements are organised in the form of tuples (records) and set of tuples form tables.

(b) Hierarchial Data Base Model: In this model data organised in a hierarchial manner.

(c) Network Database Model: In this model related data items are linked by pointers to form a network. All related items can be accessed by tracking through the pointers (links).

Among the three database models relational database model is the most popular model. Network model has associated record at a time language that must be embedded in a host programming language. There is no standard language for the hierarchial model, although most hierarchial DBMS have record at time languages.

Calculate the degree of freedom for eutectic reaction for an iron-carbon alloy and an iron-chromium-nickel alloy, under 1 atmosphere.

Degree of freedom for eutectic reaction for an iron-carbon alloy under 1 atmosphere. According to phase rule or Gibbs rule. Eutectic reaction for an iron-carbon alloy have binary phase diagram.

F = C-P+2
F = Degree of freedom
C = Number of components
P = The number of phases

Here, in the case
C = 2, P = 2
so, F = 2-2+2=2
The degree of freedom for eutectic reaction for an iron-carbon alloy is 2

For iron-chromium-nickel alloy, the degree of freedom.
Here, in this case three component system give rise to ternary diagrams.
F = C-P+1
C = 3, P = 2
So, F = 3-3+1 = 1.

The degree of freedom for eutectic reaction for an iron-chromium nickel alloy is 1.

Brass has a peritectic reaction at a temperature of 903 degree C, with 36.8% Zn (beta phase) in the middle and 32.5% Zn at alpha phase end and 37.5% Zn at liquidus end. Find out the percentages of liquid phase and alpha phase present at the peritectic point.

Percentage of liquid phase = XZ/XY * 100
XZ = 37.5 - 36.8 = 0.7
XY = 37.5 - 32.5 = 5
= 0.7/5 * 100 = 14%
When the liquid reacts with the crystals precipitated out of liquid and forms new type of crystals.