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 the process of allowing multiple signals from different sources to share common communication channel. That is a single channel is used by different signal sources to send their signals.

There are many types of multiplexing some of them as
(a) TDM (Time Division Multiplexing
(b) FDM (Frequency Division Multiplexing)
(c) WDM (Wavelength Division Multiplexing)
(d) CDM (Code Division Multiplexing

TDM: In TDM signals are separated in time domain. Signals from various sources are allowed to flow through the common line one at a time for fixed time. Suppose there are 4 signal sources, then each signal source will be allowed to use line for a period t. Once all signal sources transmit for period t, the first one again get chance and so on.

FDM: In FDM signals are separated in frequency domain. Signal from each source is modulated to different frequency so that the frequency spectrum after modulation will not overlap. At receiving end, signals are 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.

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

File organisation defines how records in a file are related to one another. Different file organisations are designed to optimise performance for one or both file access methods. There are several common file organisations. They are:

(a) SEQUENTIAL FILE: Here records are arranged in a sequence adjacent to one another. Records are accessed sequentially. To read a file record, the records starting from first record onwards is read (or from current record onwards is read) until the desired record is found.

(b) RELATIVE OR DIRECT FILE: Here record occurrences are physically located at an address that is calculated from its primary key field. The calculation of the address from the key field is called hashing. Thus record occurrences are scattered on the storage device instead of being arranged next to one another. Records can be retrieved rapidly applying the hashing formula to the primary key field of the desired record. Relative files are very good for situations where rapid access to a small percentage of records in a file are needed by programs.

INDEXED FILES
Here records are pointed to by indexes. The advantages of an index is that it is relatively small and easy to update. At a maximum, the file will have one index per primary key. This index point to the exact location where data (record) is stored. If not maintained properly, indexes can become corrupt and require rebuilding.

INDEXED SEQUENTIAL FILE: This is a special variation on the indexed file concept. Records are physically arranged in sequence to allow sequential access, in contiguous locations or using a linked list or both. These file also contain an index of record keys and their physical addresses that can be used to provide semi direct access to records within the sequential file. Each program determines how it want to access the records, whether sequentially 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.

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 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 organisation. Due to strategic information systems, a competitive edge over the other organisations 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, eGovernance system for policy management.

Important components of strategic information system are:-

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

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

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

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

MULTIPROGRAMMING:- It is the process by which CPU executes programs that reside in memory on time sharing basis. In a multiprogramming 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.

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.

An example of single user operating system is DOS. An example of multiuser operating system is UNIX.

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

COMPILERS: They are software that translates program written in high level language to machine language. Compilers are complex programs.

ASSEMBLERS: They are software that translates programs written in assembly language to machine language.

TRANSLATOR: Translators are software than can convert programs written in one language to another language. Compilers, interpreters, assemblers etc. are example of translators.

Compilers use many phases for conversion. They are:-

LEXICAL ANALYSIS: Checking for invalid symbols in program.

SYNTAX ANALYSIS: Checking validity of syntax used.

CODE GENERATION: Convert each statement to equivalent machine code.

CODE OPTIMISATION: Generated code is analyzed for redundancy and optimal code is generated.

Assemblers usually uses two or three phases (passes) for converting assembly language program to machine language program. In the first pass, macro calls are expanded. In the second pass forward references are resolved and in the third pass actual machine code generation is done.

Once software is developed using high level languages, compilers are essential for translation. Similarly, assemblers are required for translation in places where programs are developed in assembly 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 conected 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 are the major forms of Stratification System?

Caste: Caste is real organized group of society. In caste social status of individual varies. Some are higer some are lower. There is no definite geographical location. Endogamous 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 behaviour. 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 moulding 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.

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.

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 intercrystalline 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 intercrystalline. 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 austenitic region (i.e. above A3 temperature) to room temperature.

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 recrystallization 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 recrystallization temperature.

Give two applications of nano materials?

(a) Next-generation computer chips
(b) Kinetic energy penetrators with enhanced lethality

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.

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 utilises 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 worshipped 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 womanfolk 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.

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 alongwith 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 verifications made by them. So science and technology are incomplete without each other.

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

No. of slip systems are required for plastic deformation in polycrystalline materials = 2 Nos.

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 equipments 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.

Write down the Slip Plane and Slip Direction (one plane and one direction only) of Nickel (only Miller indices). How many slip systems are there in Nickel ?

A Slip Plane and a Slip Direction that lies on it together constitute a slip system. For example, the combination (111) and [110] forms a slip system, but not (111) and [110], as the [110] direction does not lie on the (111) plane.

Counting the slip systems for the most densely packed slip planes only, there are 12 slip systems in FCC and BCC crystals for Nickel.

Atomic radii of two metal atoms are 0.128 nm and 0.133 nm respectively. Find out whether they form an solid solution and if they form, state what type of solid solution it is.

%age change in radii
= 0.133-0.128/0.128
= 0.03906
= 3.91%
3.91% less than 15%
Hence they form solid solution, type of solid solution - solid solubility.

The final thickness of a hard copper sheet is 1.0 mm. It was produced by cold working with 25% deforestation. What was the starting thickness of the metal before the cold working ? To decrease the hardness what will you do ?

Final thickness of a hard copper sheet = 1.0 mm
25% deformed
Suppose, x = 0.25
So that 0.75x = 1
x = 1/0.75 = 1.33
To decrease the hardness, we will do further normalising.

Differentiate Between Culture and Civilization.

(a) Culture means development of tastes in art, literature and music whereas Civilization though quiet ancient yet is outcome of culture.

(b) Culture advances slowly and steadily whereas Civilization move continuously towards upward trend.

(c) Culture has instrinsic quality and cannot be adopted quickly whereas Civilization can be transferred from one generation to another quickly.

(d) Like mindedness is the basic requirement of culture whereas Civilization is passed with much efforts.

(e) Culture cannot be improved. How work of Milton and Tagore can be improved whereas work of Civilization can be improved by any body who has lesser thinking power.

What is the Role of Brain storming in design idea generation.


Brain storming is defined as a method to practice a conference technique by which a group attempts to find different concepts for a specific need by gathering or collecting all the ideas spontaneously contributed by its members.

In this stage brainstorming is important, however, we cannot use brainstorming without going through the process. The basic concept of brainstorming is to generate a large quantity of ideas. The more the ideas, higher the probability of the desired product.

The following are the members of the brainstorming session:

1. Designers
2. Engineers
3. Executives
4. Marketing experts
5. Psychology experts etc

Participants must be involved and achieve results in the session. The topics of brainstorming session is given to the members before the session starts and the duration of the session is upto an hour because the energy level needed for such session is high. A set of rules are developed for any brainstorming session.

1. No critism of ideas during the session. One way to prevent the critism is to disallow discussion during the session, present the ideas in brief and in short format. One of the participants in the group will need to collect all ideas or use a sticker for each idea.

2. Wild, silly and crazy ideas are welcome. Such ideas may help others to generate solid ideas or help for fun and humorous environment.

3. Generate as many ideas as possible. One way to do so is to appoint a facilitator who will keep rotating the turns without allowing break time. Keep the competition spirit alive. Some people produce more ideas when competing with others in a group.

4. Adding to or improving presented ideas are welcomed.

Techniques in use for brainstorming are:
1. Creative techniques
2. Osborn's Brain storming technique
3. Phillips 66 Buzz session technique
4. Crawford slip writing technique

Explain Robust Design.


A robust design is one in which the function and performance of the product or process are relatively insensitive to variations to any of the noise factors given below:

A noise factor is a source of variation that is impossible or difficult to control.

Type of noise factors--
1. Unit to Unit noise factor: These are random variations in the process and product caused by variability in raw materials, machinery and human participation. They are associated with a production process that is in statistical control.
2. Internal noise factor: These variations are internal to the product or process. They include (a) time dependant factor such as wear of mechanical component (b) operational errors, such as improper setting of the product or machine tool.
3. External noise factor: An external noise factor is a source of variation that is external to the product or process, such as temperature, pressure, voltage etc.

In product design, robustness means that the product can maintain consistent performance with minimal disturbance due to variations in uncontrollable factors in its operating environment.

In process design, robustness means that the process continues to produce good product with minimal effect from uncontrollable variations in its operating environment.

What do you mean by Social Mobility? What are the different types of Mobility?

Change from one status to another is called Social Mobility. Social Stratification is also the result of Social Mobility. Any change in the value-scale or any change in the characteristic results in a change in the status of different classes. Thus different occupations are held in different degrees of esteem in different societies. The members of priestly class enforced high rank at one time than that of a doctor and engineer in India. But today it is not like that. A doctor or engineer has more prestige and esteem. Thus it is experienced that people continue to move up and down in the status scale. This movement is called Social Mobility and should not be confused with migration which is called movement in geographical space. Social Mobility can take one of these forms. A change involving in an individual's life time turn one's status to another as plumber to that of carpenter is called horizontal mobility. Vertical Mobility can be either upward or downward.

Differentiate between standardization and specification giving appropriate examples. How are 'preferred numbers' useful in standardization? Explain with the help of a suitable example.

Standardization is the process of establishing standards or units of measure by which extent, quality, quantity, value performance, may be compared and measured.

The following standards are used for designing products:
(i) Standards for materials, their chemical compositions, their physical properties (e.g. mechanical) and heat treatment.
(ii) Standards for fits, tolerances and surface finish of components.
(iii) Different shapes and dimensions of commonly used machine elements e.g., nuts, bolts, rivets, gears etc.

Now the product specification includes such as dimensions of the components e.g. Volume, area, weight, speed, load, power etc. are expressed numerically e.g. 10 kw, 20 kN, 500 r.p.m or 10 kg etc.

Preferred numbers are used to specify such specification because a company may manufacture different models of same product.

The system is based on the use of geometric progressive to develop a set of numbers.

There are five basic series, denoted by R5, R10, R20, R40 and R80, which increased in steps of 58%, 26%, 12%, 6% and 3% respectively.

The series is obtained by taking the first number and multiplying it by a series factor to get the second number.

E.g. Consider a company manufacture of lifting machine who wants to introduce six different models of capacities ranging from 50kN to 100kN.

Considering R20 series, the capacity of different models of lifting machine will be 55 KN using R20 series--> 20/10 = 1.12

55 * 1.12 = 61.6 = 61 KN,
61 * 1.12 = 68.32 = 68kN,
68 * 1.12 = 76.16 = 70kN,
76 * 1.12 = 85.12 = 85kN,
85 * 1.12 = 95.2 = 95kN

Discuss the criteria for the assessment of appropriate technology.


Appropriate Technology: Be-fitting technology is called appropriate technology. Who do not want appropriate technology to feed the rapidly growing population. After all application of technology shall ensure optimum use of natural resources which may remain unutilized or underutilized in the absense of the same. No doubt in the past quarter of a century the developing countries like India have made progress in terms of increasing per capita income of their rapidly growing population. Of course progress has also been made in the fields of health, education and infrastructure (electricity, water, transportation and communication) but despite this growth record, poverty has not been lessened appreciably. Levels of unemployment and income inequality and increasing. According to the World Bank almost half of the total population of the developing world live in absolute poverty. Such people are denied basic components of average living, adequate clothing and housing and access to basic services such as clean water, energy, schools and health facilities which are taken for granted by most people in developed countries.

Appropriate technology means method of doing a given job or work in a benefiting manner and style as per the liking of users. We can say that an appropriate technology is one which is best suited to the environment in which it is most suitable. The idea of appropriate technology was first welcomed and received by third world countries. The third world countries are underdeveloped developing countries. India and host of many other countries are called third world countries. The concept of appropriate technology appeared first in the mind of great thinker Schumacher and we can find its reference in his famous work 'Small is Beautiful'.

Discuss the impact of technological and cultural factors on Social Change.


(i) Geographical mobility in an industrial society is very important for job promotion. The workers must go to those places where they expect promotion. Rapid industrialization uproot the members of the family and separate them from the strong tie of kinship. This weakens the hold of family and bring about structural change drastically.

(ii) An industrial society offer a number of economic opportunities with better prospects of social mobility. Socially mobile people gain many experiences concerned with education, interests and tastes of which they remain deprived of while extended in conventional ridden family. With the result, the bonds of common interest between the relatives in the extended family are lessened or even shattered.

(iii) In big towns and cities, people turn to agencies than the family in order to meet their many needs. Non-kin organizations such as schools, hospitals and recreation as well as welfare centres assume many functions including child-care and socialization performed by family. With the result, the very bonds which kept the extended family together in one circuit begin to dissolve. People began to seek new foundation of married life having thick companionship with single spouse and children being looked as individuals rather than productive units.

(iv) Industrialization ensures better socio-economic status which was recognized by birth and the importance of kinship in a traditional extended family. Individual's goals have become important than kinship obligations. Personal freedom in matters of mating and place of residence has further brought sufficient changes in the family.

(v) Children in a modern society are being looked at as economic liability than economic asset. The parents receive no economic gain from the vast expenditure they incur in feeding and educating their children. As soon as the young one are able to earn, they leave home and start forming separate families. People prefer and find it convenient to live away in a isolated places as an independant units.

Is Sociology a Science? Discuss.

There is great controversy about the nature of sociology as a science. Some critics deny sociology to be claimed as science while other argues that it is science. Before explaining whether 'sociology' is science or not, it would be proper to know the meaning of science. Science is a systematised body of knowledge concerning cause and effect of a particular phenomenon. Science refers to logical and systematic methods of which knowledge of the universe is obtained and to the actual body of knowledge produced by these methods. The sciences are conventionally divided into two parts - natural sciences and social sciences. Natural science deals with the physical and biological phenomenon and the social science studies various aspects of human behaviour. There are important differences between the two. Sociology is a social science. Now the question arises what constitute natural science and if at all sociology should be called natural science and if at all sociology should be called natural science then what those grounds are? To support sociology is a science we give following points:

(1) A sociology is bound to be methodological and systematic in his approach. His question need to be clear, precise. The questions are to be specific and not ambiguous (vague or full of doubts.)

(2) Data which sociologist collect are best suited for future predictions.

(3) Data collected by socilogist are based on observations and they are classified in latter stages of research.

(4) Carefully concluded results of a sociologist have universal application. These results can be tested under all circumstances and at all times.

(5) Relationship between cause and effect is fully and well recognised in the study of sociology. The only difference is that socilogist concepts cannot be tested in the laboratory as done in case of physical sciences because they deal with human behaviour which changes from time to time.

Discuss the changing role and functions of family.

Family as an association of men and women staying together in a common dwelling (house) place alone or with children having economic interdependence engaged in procreation (production) and upbringing of children.

Functions and role of family as a form of social control:-
1. Regulation of sexual behaviour is the basic function of family system. Sexual behaviour is not a matter of private choice and no society would permit to do mating at random. The marriage and family system, provides means of regulating sexual behaviour by permitting who mate with whom.
2. Replacement of members from one generation to another generation is necessary for survival of the society.
3. Family is the earliest and most important agency of Socialization.
4. Family offer care, protection, security, love affection shelter and warms to infant. It also provides material and emotional support.
5. Social behaviour of human is controlled by family his etiquettes behaving and dealing other social members is controlled through family.

Differentiate between Frenkel and Schottky defects?

Frenkel Pairs: One such type of defect involves a cation-vacancy and a cation- interstitial pair. It might be thought of as being formed by a cation leaving its normal position and moving into an interstitial site. There is no change in charge because the cation maintains the same positive charge as an interstitial. This is called a frenkel defect.
e.g. closed packed structures have fewer interstalices and frenkel defects, because additional energy is required to force the atom into a new position.

Schottky defect: The removal of a positive ion to create a vacancy must be counter balanced by the removal of a negative ion in order to maintain neutrality. The pair of vacancies is termed as schottky defect.
e.g. with a sodium chloride crystal, the removal of a positive sodium ion is balanced by the removal of a negative chlorine ion in order to maintain neutrality.

Describe Fick's first law of diffusion. A plate of iron is exposed to a carburizing atmosphere on one side and a decarburizing atmosphere on the other side at 700 degree C. Under steady state condition calculate the diffusion flux of carbon through the plate, if the concentration of carbon at position of 5 mm and 10 mm beneath the carburizing surface are 1.2 kg/m3 and 0.8 kg/m3, respectively. Assume a diffusion coefficient of 3 * 1011 m2/s at this temperature.

Fick's First Law of Diffusion: The rate at which particles diffuse in steady state conditions i.e. when there are no changes in the system with time, the rate of diffusion is proportional to the concentration gradient dC/dx, this is known as Fick's First Law.

From the Fick's first law,
J= -D dC/dx

is utilized to determine the diffusion flux.

Substitution of the value above into this expression yields.

J = -D CA-CB/xA-xB

where, D = 3 * 10-11 m2/s

CA = 1.2 kg/m3, CB = 0.8 kg/m3

xA = 5 * 10-3 m ; xB = 10-2 m

J = -D CA-CB/xA-xB = -(3 * 10-11) 1.2-0.8 kg/m3/(5 * 10-3-10-2) m

J = 2.4 * 10-9 kg/m2-s

Mention different types of Bravais lattices possible in crystalline materials. Show that the atomic packing factor (APF) of FCC crystal structure is 0.74.

The French mathematician Bravais from geometrical considerations that there can be only 14 different ways in which similar points can be arranged in three dimensional space. Thus, the total number of space lattices belonging to all the seven crystal system put together is only 14. These are known as Bravias Lattice.


Atomic packing factor of FCC and BCC crystal: In the FCC unit cell illustrated, the atoms touch one another across a face-diagonal the length of which is 4 R. Since the unit cell is a cube, its volume is a3, where a is the cell edge length.


From the right triangle on the face,

a2 + a2 = (4R)2

a = ∫8R = 2R∫2

The FCC unit cell volume Vc may be computed from

Vc = a3 = (2R∫2)3 = 16R3∫2 ANS.

The APF (atomic packing factor) is defined as the function of solid sphere volume in a unit cell.

APF= Total sphere volume = Vs
Total unit cell volume = Vc


Both the total sphere and unit cell volumes may be calculated in terms of the atomic radius R.



Face-centred Cubic (F.C.C.) structure

The Volume for a sphere = 4/3 πR³

Since there are 4 atoms per FCC unit cell

Number of atoms in all six faces = ½ x 6 =3

Number of atoms in all corners = 1/8 x 8 = 1

Total number of atoms = 3 + 1 = 4

The total FCC sphere volume is

Vs = 4 x 4/3 πR³ = 16/3 πR³

The total unit cell volume is Vc = 16 R³ ∫2

The atomic packing factor is

APF = Vs/Vc = 16/3 πR³/16 R³∫2 = 0.74