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Thursday, 16 July 2015

Parallel Computing-Model question paper for B.E/B.Tech Computer Science Engineering

1(a) Why do you think that parallel processing with large number of nodes has been still in infancy as far as general purpose computing is concerned? (4 Marks)
(b) Give two reasons why Amdahl’s law should hold? Is it possible that there are cases where the law may fail? If yes, explain. (6 Marks)
(c) Do you find any machine that does not fit into Shore’s classification scheme? Explain. (6 Marks)
(d) A processor had no floating point unit in earlier version but was added to it later. The speedup for floating point operations is 500 compared to software implementation of floating point routines. Find the speedup for programs that has floating point operations in the original machine consuming 10%, 20% and 90% of time. (4 Marks)
2(a) Using a neat sketch explain electronic implementation of a pipeline. (6 Marks)
(b) Write a note on optimal pipe segmentation. (6 marks)
(c) Distinguish between fixed point addition pipeline and floating point add pipeline using neat sketches. (8 Marks)
3(a) Control of a pipeline instruction processor poses a number of problems. Explain. (6 Marks)
(b) Using a neat figure, explain the instruction processing pipeline in superscalar processor. (8 Marks)
(c)Given 3-stage multiplier pipe and 2-stage adder pipe and delays, draw a schematic of a chained pipeline for doing the following vector computation on vectors A,B,C and Y. Yi=(Ai-2 + Bi)*Ci-3 + Di+1 (6 Marks)
4(a) Give the schematic design of a scheduler that implements following latency cycle for dynamically configured pipe running for operations A, B, C and D. Give the number of initiations per clock (IPC). Latency cycle = <2AD 3ABC 1BD 2AC> (8 Marks)
(b) Write a note on static branch prediction. (4 Marks)
(c) Prove that the average latency of any greedy cycle (simple) is less than or equal to the number of 1’s in the collision vector (d0 is included) of the reservation table. (8 Marks)
5(a) Work out an algorithm to multiply two 4x4 matrices on a hypercube machine having 16 nodes. (6 Marks)
(b) A data item is to be distributed to all the PEs. Find out the data routing steps to carry out the job for hypercube connected machine. (6 Marks)
(c) A ring connected SIMD parallel computer is to add n numbers. Work out a parallel algorithm to add these n-node rings. How many routing steps will be required? What is the time complexity to perform the n number addition on n-node ring machine? (8 Marks)
6(a) Write a note on ILLIAC IV Computer. (4 Marks)
(b) Draw and explain different communication ports of PE in a mesh connected computer. (4 Marks)
(c) Assume a 64 node mesh connected machine having the 64 records of 64 students. It is desired to find all students having more than 90% marks. Work out the program schematic for the problem. What is the speedup obtained? (6 Marks)
(d) A two dimensional matrix of 8x8 contains real numbers. It stands for the values of pixels of same image. A simple smoothing algorithm requires to smoothen out the image so that every element of the matrix is replaced by the average value of the four neighbors. Formulate the parallel algorithm and code it for the machine discussed. (6 Marks)
7(a) Illustrate the data routing from node 6 to 14 in a single stage shuffle exchange network. (6 Marks)
(b) How many steps shall be required for routing a data item from one node to another in a 32 node Omega network. Explain. (4 Marks)
(c) Illustrate the routing algorithm for the 8x8 Benes network with permutation p = [1  3  5  7  6  8  9  0  4  2  11  10] (6 Marks)
(d) Design an 8x8 cross bar using digital logic elements. (4 Marks)
8(a) What is the effect of low and high value of τ on SLT network? (4 Marks)
(b) Can 2 input XORs be implemented using 3 neurons? If yes, show the neural network with its weights. (6 Marks)
(c) Take a 3 PML node 2 input 3 class neural network and illustrate the training algorithm for classification for 2 classes. (6 Marks)
(d) State and explain Hebb’s learning (Delta rule). (4 Marks)

Tuesday, 7 July 2015

Mechanics of Materials- Model question paper for B.E/B.Tech Mechanical engineering

1(a) State St.Venant’s principle. (4 Marks)
(b) Write a brief note on properties of engineering materials.(6 Marks)
(c) Deduce a relation between Young’s modulus and Rigidity modulus. (6 Marks)
(d) A steel press has four tension members. Each member has a diameter of 16 mm. The largest load to be resisted by the press is to be 48 kN. Determine axial stress in the tension members. (4 Marks)
2(a) Prove that normal stress acting on maximum and minimum shear stress planes is the average of any two orthogonal normal stresses acting on the point. (8 Marks)
(b) Write a note on construction of Mohr’s circle. (8 Marks)
(c) A round bar of 30mm diameter is subjected to an axial compressive force P. Taking the allowable stresses for the material of the bar as 110 MPa in compression and 50 MPa in shear, determine the magnitude of maximum value of P which can be applied such that the member does not fail. (4 Marks)
3(a) The magnitude of bending moment at a section will be maximum or minimum when the shear force at that section is zero or changes its sign. Explain. (8 Marks)
(b) A 6m long beam simply supported its ends is subjected to UDL of 30 kN/m over 2 meters length from LHS support. Draw the SF and BM diagrams. (8 Marks)
(c) A 6 meters long beam is simply supported such that there is a over hang of L meters on either support. The beam is subjected to load W at its either ends. Determine W and L such that maximum bending moment and maximum shear stress induced in the beam are 30 kN-m and 15 kN respectively. (4 Marks)
4(a) What are the assumptions made during the derivation of equations related to theory of pure bending. (6 Marks)
(b) What is section modulus? Find the section modulus of a hollow circle. (6 Marks)
(c) A beam with I section has two equal flanges of each 220 mm wide and 12 mm thick. The web has 12 mm thickness and depth 460 mm. Determine the percentage of moment of resistance shared by the flanges and web, when the section is subjected to bending moment M. (8 Marks)
5(a) Derive the moment-curvature relationship for the deflected curve. (8 Marks)
(b) Macauleys method is an improved version of double integration method which can be used for finding the deflections of beams subjected to discontinuous loads. Explain. (8 Marks)
(c) A 2 meters long cantilever is subjected to UDL of 10 kN/m throughout its length and a vertically downward point load 20 kN at its free end. Taking E=200 GPa and maximum deflection as 0.3 mm, determine the width and depth of rectangular section. Depth of the section is twice the width. (4 Marks)
6(a) Show that shear stress distribution in any section of a shaft is directly proportional to the torque applied. (5 Marks)
(b) Explain the terms torsional rigidity and torsional flexibility. (6 Marks)
(c) Compare the mass of solid shaft with that of hollow shaft of same length, when they are made of same material and are to transmit same power at same speed. The outer diameter of hollow shaft is 1.4 times its inner diameter. Maximum shear stresses induced in both cases are equal. (5 Marks)
(d) A 1m long wire is hung in vertical position and disc is attatched at the bottom end. Diameter of the wire is 2 mm. Material of wire has yield stress in shear of 150 MPa. Determine the angle through which the disc can be rotated so that the wire does not yield. Take G= 80 GPa. (4 Marks)
7(a) Develop Euler’s buckling load formula for the column with both ends hinged. (6 Marks)
(b) Write a note on limitations of Euler’s formula. (4 Marks)
(c) Derive Rankine-Gordon formula. (6 Marks)
(d) A column 2.6 meters long with a square section of side 50 mm is to be replaced by a column with hollow square section of outer side 70 mm. Determine the wall thickness of the column and percentage saving in material. Both ends of the column are hinged. (4 Marks)
8(a) Show that the volumetric strain is the sum of longitudinal strain and twice the circumferential strain. (6 Marks)
(b) Radial and circumferential stresses in a thick wall pressure vessel vary parabolically across the section of the wall, while longitudinal stress is uniform throughout the cylinder. Explain. (6 Marks)
(c) A pressure vessel with outer and inner diameters of 400 mm and 320 mm respectively is subjected to an external pressure 8 MPa. Determine the circumferential stress induced at the inner and outer surfaces. (4 Marks)
(d) A water pipe with 500 mm diameter supplies water at 51 meters head. Taking allowable stress for pipe material as 30 MPa and efficiency of circumferential riveted joint as 80%, determine the thickness of the pipe. Specific weight of water is 9.81 kN/m3. (4 Marks)

Field theory-Model question paper for B.E/B.Tech

1(a)  A uniform volume charge distribution exists in a spherical volume of radius a. Using the concept of  energy density or otherwise, find the total energy of the system.  (6 Marks)
(b) Three charges -1(µC), 4(µC) and 3(µC) are located in free space at (0,0,0), (0,0,1) and (1,0,0) respectively. Find the energy stored in the system. (4 Marks)
(c) Transform the vector A = y ax – x ay + z az into cylindrical co-ordinates. (4 Marks)
(d) The electric potential in the vicinity of the origin is given as V = 10x2 + 20 y2 + 5 z2 (V). What is the electric field intensity? Can this potential function exist? (6 Marks)
2(a) Determine the capacitance of a parallel-plate capacitor consisting of  two parallel conducting plates of area A and separation d. (6 Marks)
(b) Using Laplace’s equation, obtain the potential distribution between two spherical conductors separated by a single dielectric. The inner spherical conductor of radius ‘a’ is at a potential ‘V0’ and the outer conductor of radius ‘b’ is at potential 0. Also find variation of E. (8 Marks)
(c) A cubical region of space is defined by the surfaces x=1.8, y=1.8, z=1.8,x=2, y=2 and z=2. If D=3y2ax+3x2yax (C/m2);
(i) Find the exact value of the total charge enclosed within the cube by surface integration.
(ii) Find an appropriate value for the enclosed charge by evaluation of derivatives at the centre of the cube.  (6 Marks)
3(a) State Ampere’s circuital law. (4 Marks)
(b) State Stoke’s theorem. (4 Marks)
(c) Show that the magnetic flux density B set up by an infinitely long current-carrying conductor satisfies the Gauss’s law. (4 Marks)
(d) A cylinder of radius ‘b’ and length ‘L’ is closely and tightly wound with N turns of a very fine conducting wire. If the wire carries a dc current I, find the magnetic flux density at any point on the axis of the cylinder (solenoid). What is the magnetic flux density at the centre of the cylinder? Also, find B at the ends of the cylinder. (8 Marks)
4(a) Write a note on magnetic torque and moment on a closed circuit. (6 Marks)
(b) What are magnetic circuits? Distinguish between linear and non-linear magnetic circuits. (10 Marks)
(c) Through a suitable experiment on a magnetic material, the magnetic flux density B is found to be 1.2 T when H=300 A/m. When H is increased to 1500 A/m, the B field increased to 1.5 T. What is the percentage change in the magnetization vector? (4 Marks)
5(a) Find the self-inductance per unit length of an infinitely long solenoid. (6 Marks)
(b) A steady state current is restricted to flow on the outer surface of the inner conductor (ρ=a) and the inner surface of the outer conductor (ρ=b) in a coaxial cable. If the coaxial cable carries a current I, determine the energy stored per unit length in the magnetic field in the region between the two conductors. Assume that the dielectric is non-magnetic. (8 Marks)
(c)  Consider two coupled circuits having self-inductances L1 and L2 that carry currents I1 and I2 respectively. The mutual inductance between the two coupled circuits is M12. Find the ratio I1/I2 that makes the stored magnetic energy Wm a minimum. (6 Marks)
6(a) State Faraday’s law. Derive Maxwell’s equation in point form from faraday’s law. (8 Marks)
(b) Show that for a sinusoidally varying field, the conduction current and the displacement current are always displaced by 900 in phase. (4 Marks)
(c) The dry earth has a conductivity 10-8 S/m, and a relative permittivity 4. Find the frequency range on which the conduction current dominates the displacement current. (4 Marks)
(d) Write Maxwell’s equations in integral form. (4 Marks)
7(a) Derive the differential form of continuity equation from the Maxwell’s equations. (4 Marks)
(b) Write the set of four Maxwell’s equations in terms of eight scalar equations in Cartesian coordinates. (12 Marks)
(c) Consider the wet earth with the following properties: ε = 30 ε0 μ = μ0  σ = 10-2 S/m. Determine the ratio of amplitudes of conduction and displacement currents at 100 MHz. (4 Marks)
8(a) Write the phasor and time-domain forms of a uniform plane wave having a frequency of 1 GHz, that is traveling in the +x=direction in a medium of ε = 12ε0
μ = μ0. ( 6 Marks)
(b) Define skin depth. Prove that high frequency resistance is very much greater than dc resistance. (6 Marks)
(c) State and explain Poynting’s theorem. (5 Marks)
(d) Determine the critical angle if the refractive index of the medium is 1.77. (3 Marks)

Wednesday, 1 July 2015

Computing fundamentals and C Programming-Model question paper for B.E/B.Tech Computer Science Engineering

1(a) What is the major change in the fourth-generation computers? What are the various characteristics of the computers of this generation? (6 Marks)
(b) What is a computer network? Describe different types of computer networks in use today. (6 Marks)
(c) What is an operating system? What are the various categories of operating systems? (4 Marks)
(d) How do we create and sort a list of data items? (4 Marks)
2(a) Write the algorithm to determine whether a number is positive, negative or zero. (3 Marks)
(b) What is high-level language? What are the different types of high-level languages? (5 Marks)
(c) Write a C program to calculate the sum of n integer numbers. (8 marks)
(d) A class of 50 students sits for an examination which has three sections A,B and C. Marks are awarded separately for each section. Draw a flowchart to read these marks for each student. (4 Marks)
3(a) Describe the process of creating and executing a C program under UNIX system. (6 Marks)
(b) The line joining the points (2,2) and (5,6) which lie on the circumference of a circle is the diameter of the circle. Write a program to compute the area of the circle. (6 Marks)
(c) A programmer would like to use the word DPR to declare all the double-precision floating point values in his program. How could he achieve this? (4 Marks)
(d) What is an unsigned integer constant? What is the significance of declaring a constant unsigned? (4 Marks)
4(a) Describe the purpose of commonly used conversion characters in a printif() function. (4 Marks)
(b) Given the values of the variables x, y and z. Write a program to rotate their values such that x has the value of y, y has the value of z, and z has the value of x. (6 Marks)
(c) Find errors if any, in the following switch related statements. Assume that the variables x and y are of int type and x=1 and y=2.
(i) switch (y);
(ii) case 10;
(iii) switch (x+y)
(iv) switch (x) {case 2: y = x + y; break};                                                          (4 Marks)
(d) Write a program to determine whether a given number is ‘odd’ or ‘even’ and print the message NUMBER IS EVEN or NUMBER IS ODD without using else option. (6 Marks)
5(a) Can we change the value of the control variable in for statements? If yes, explain its consequences. (4 Marks)
(b) How can we use for loops when the number of iterations are not known? (4 Marks)
(c) What is a dynamic array? How is it created? Give a typical example of use of a dynamic array. (6 Marks)
(d) Write a program that will count the number of occurrences of a specified character in a given line of text. (6 Marks)
6(a) Describe the limitations of using getchar and scanf functions for reading strings. (6 Marks)
(b) Compare the working of the following functions:
(i) strcpy and strncpy; (ii) strcat and strncat; and (iii) strcmp and strncmp. (6 Marks)
(c) s1, s2 and s3 are three string variables. Write a program to read two string constants into s1 and s2 and compare whether they are equal or not. If they are not, join them together. Then copy the contents of s1 to the variable s3. At the end, the program should print the contents of all the three variables and their lengths. (8 Marks)
7(a) Describe the two ways of passing parameters to functions. When do you prefer to use each of them? (6 Marks)
(b) What is prototyping? Why is it necessary? (4 Marks)
(c) What are the rules that govern the passing of arrays to function? (4 Marks)
(d) Write a function that will scan a character string passed as an argument and convert all lowercase characters into their uppercase equivalents. (6 Marks)
8(a) How does a structure differ from an array? (4 Marks)
(b) What is a ‘slack byte’? How does it affect the implementation of structures? (4 Marks)
(c) What are the arithmetic operators that are permitted on pointers? (4 Marks)
(d) Write a program that reads a file containing integers and appends at its end the sum of all the integers. (8 Marks)

Friday, 26 June 2015

Applied Mechanics and Strength of Materials-Model question paper for B.E/B.Tech Civil Engineering

1(a) What are the methods for finding out the resultant force for a given system of forces? (4 Marks)
(b) Discuss the classification of couples and explain clearly the difference between a positive couple and a negative couple. (5 Marks)
(c) Show that if three coplanar forces, acting at a point be in equilibrium, then, each force is proportional to the sine of the angle between the other two. (6 Marks)
(d) A tricycle weighing 200 N has a small wheel symmetrically placed 500 mm in front of two large wheels which are placed 400 mm apart. If the centre of gravity of the cycle be at a horizontal distance of 150 mm from the rear wheels and that of the rider, whose weight is 150 N, be 100 mm from the rear wheels, find the thrust on the ground under the different wheels. (5 Marks)
2(a) Explain Routh’s rule for finding out the moment of inertia of an area. Explain where it is used and why? (4 marks)
(b) Obtain a relation for the maximum and minimum horizontal force required to maintain equilibrium of a body lying on a rough inclined plane. (6 Marks)
(c) What is a ladder? How will you find out the frictional force between the ladder and floor? (4 Marks)
(d) a right circular cylinder of 12 cm diameter is joined with a hemisphere of the same diameter face to face. Find the greatest height of the cylinder, so that c.g. of the composite section coincides with the plane of joining the two sections. The density of the material of hemisphere is twice that of the material of the cylinder. (6 Marks)
3(a) Obtain an equation for the maximum mechanical advantage and maximum efficiency of a machine. (6 Marks)
(b) What is a screw jack? On what principle does it work? Derive a relation for the velocity ratio of a simple screw jack and differential screw jack. (6 Marks)
(c) State the difference between Weston’s differential pulley block and a geared pulley block. (4 Marks)
(d) A stone is thrown vertically upwards, from the ground, with a velocity 49 m/s. After 2 seconds, another stone is thrown vertically upwards from the same place. If both the stones strike the ground at the same time, find the velocity, with which the second stone was thrown upwards. (4 Marks)
4 (a) At what angle, the projectile should be projected in order to have maximum range? Justify your answer by calculations. (6 Marks)
(b) Explain the term ‘recoil of gun’. Explain the method of determination of the velocity of the bullet. (6 Marks)
(c) A train of mass 200 tonnes is ascending a track, which has an inclination of 1 in 100, the resistance being 75 N per tonne. What is the acceleration of the train when its speed has reached 18 km per hour, if the power developed by the engine is 450 kW. (4 Marks)
(d) A wheel rotates for 5 seconds with a constant angular acceleration and describes during this time 100 radians. It then rotates with a constant angular velocity and during the next five seconds describes 80 radians. Find the initial angular velocity and the angular acceleration. (4 Marks)
5(a) What are statically indeterminate problem? Explain the procedure for solving such problems. (6 Marks)
(b) Explain the procedure for finding out the stresses developed in a body due to change of temperature. (6 marks)
(c) Define strain energy and explain how it is stored in a body? (4 Marks)
(d) A round bar 40 mm diameter is subjected to an axial pull of 80 kN and reduction in diameter was found to be 0.007 mm. Find Poisson’s ratio and Young’s modulus for the material of the bar. Take value of shear modulus as 40 GPa. (4 Marks)
6(a) Explain briefly the relationship between shear force and bending moment at a section. (4 Marks)
(b) Explain by mathematical expression, that the shear stress abruptly changes at the junction of the flange and web of an I-section and a T-section. (6 Marks)
(c) Show that for a rectangular section, the distribution of shearing stress is parabolic. (6 Marks)
(d) A rectangular beam 60 mm wide and 150 mm deep is simply supported over a span of 4 meters. If the beam is subjected to a uniformly distributed load of 4.5 kN/m, find the maximum bending stress induced in the beam. (4 Marks)
7(a) What is moment area method? Explain the two Mohr’s theorems, as applicable to the slope and deflection of a beam. (6 Marks)
(b) Derive an expression for the angle of twist in the case of a member of circular cross-section subjected to torsional moment. (6 Marks)
(c) Describe briefly the various ways, in which a riveted lap joint or butt joint can fail. (4 Marks)
(d) A cantilever beam 120 mm wide and 200 mm deep is 2.5 m long. Find the uniformly distributed load, the beam should carry to produce a deflection of 5 mm at its free end. Take E = 200 GPa. (4 Marks)
8(a) Show that in the case of a thin cylindrical shell subjected to an internal fluid pressure, the tendency to burst lengthwise is twice as great as in a transverse section. (6 Marks)
(b) State the difference between a perfect frame and an imperfect frame. (4 Marks)
(c) Describe the procedure for drawing the vector diagram of a truss subjected to horizontal loads. (6 Marks)
(d) a steam boiler 800 mm diameter is made up of 10 mm thick plates. If the boiler is subjected to an internal pressure of 2.5 MPa, find the circumferential and longitudinal stresses induced in the boiler plates. (4 Marks)

Data Communication and Networks-Model question paper for B.E/B.Tech Engineering

1(a) Explain the concept of networks and types of computer networks. (6 Marks)
(b) What is TCP/IP protocol architecture? Explain. (6 Marks)
(c) Draw the block diagram of a general communication model and explain the function of each block. (8 Marks)
2 (a) Discuss salient features of OSI reference model. (6 Marks)
(b) What is the difference between virtual and actual communication? (6 Marks)
(c) Why do we use layered protocols? Give reasons. (8 Marks)
3(a) With the help of suitable waveforms explain the Manchester and quaternary NRZ formats. What are the advantages of using the Manchester format over the other formats? (8 Marks)
(b) What is the effect of twisting the wires in UTP cables? (4 Marks)
(c) State and explain various properties of line codes. (4 Marks)
(d) What is the difference between source coding and line coding? (4 Marks)
4(a) A bit stream 10011101 is transmitted using the standard CRC method. The generator polynomial is x3+1. Show the actual bit string transmitted. Suppose the third bit from left is inverted during transmission. Show that this error is detected at the receiver end. (6 Marks)
(b) Explain about the role of minimum distance in error correction and detection. (4 Marks)
(c) What is piggybacking? (4 Marks)
(d) Given an error free 64 kbps satellite channel which is used to send 512 byte data frames in one direction with very short acknowledgements coming back the other way. What will be the maximum throughput for window sizes of 1, 7, 15 and 127. (6 Marks)
5(a) What is the maximum and minimum length of frame of traditional Ethernet? Explain briefly. (6 Marks)
(b) How can you compare 1-persistent CSMA and P-persistent CSMA? What part of the 802 project makes use of CSMA/CD? (6 Marks)
(c) Why can not Ethernet and token ring be used in WAN? Explain. (4 Marks)
(d) Fast Ethernet has the same 64-byte minimum frame size but can get bits out ten times faster. How is it possible to maintain the same minimum frame size? How much bandwidth loss will occur in this case? (4 Marks)
6(a) Explain different carrier sense protocols. How are they different than collision-free protocols? (5 Marks)
(b) Describe the access method used by Ethernet (IEEE) network, and the cable and connectors used by Ethernet network. (6 Marks)
(c) Discuss briefly the advantages and disadvantages of FDDI and Ethernet LAN technologies. (4 Marks)
(d) Evaluate ring latency of 20 stations separated by 100 meters and operate at a speed of 4 Mbps. Assume the delay introduced by each station to be 2.5 bit. (5 Marks)
7(a) With the help of suitable explanatory diagrams, explain about the routers and gateways. (8 Marks)
(b) A class B network on internet has a subnet mask of What will be the maximum number of hosts per subnet? (4 Marks)
(c) What is firewall? What is the difference between packet filtering and proxy server gateways? (4 Marks)
(d) A computer on a 6 Mbps network is regulated by token bucket. Token bucket filled at a rate of 1 Mbps. It is initially filled to a capacity of 8 megabytes. How long can computer transmit at the full 6 Mbps? (4 Marks)
8(a) What is meant by fragmentation? Is fragmentation needed in concentrated virtual circuit internets, or any in datagram system? (5 Marks)
(b) Differentiate between the static and dynamic routing with their pros and cons. Give example of some routing protocols used in both type of routing. (6 Marks)
(c) Give an efficient algorithm for finding the shortest parts between all pairs of nods in a tree. What is the complexity of the algorithm? (4 Marks)
(d) An ATM network uses a token bucket scheme for traffic shaping. A new token is put into bucket every 5 Microseconds. What is the maximum sustainable net data rate. Exclude the header bits. (5 Marks)

Material science and engineering-Model question paper for B.E/B.Tech Engineering

1(a) How are materials classified? (4 Marks)
(b) Give the construction and working of Bragg’s X-ray spectrometer. (8 Marks)
(c) Discuss briefly the general usefulness of the periodic table in reference to atomic structure. (4 Marks)
(d) The workfunction of sodium is 2.3 eV. Calculate the threshold frequency and its corresponding wavelength. (4 Marks)
2(a) Give the composition, properties and uses of the following alloying steels: High speed steel, Silicon steel, Stainless steel and Tungsten steel. (8 Marks)
(b) Name the important mechanical tests which give valuable information about metals and alloys. (4 Marks)
(c) State ‘Gibb’s phase rule’. What is its importance? (4 Marks)
(d) The crack length of a sample of certain material is 4.4 μm, and the Young’s modulus of the material is 60 GN/m2. The surface energy is 1.32 J/m2. Calculate the fracture strength and compare it with the Young’s modulus. (4 Marks)
3(a) Explain the basic mechanism involved in solid solution hardening and give examples of alloys strengthened by this process. (6 Marks)
(b) What is a retained austenite? Why is it not desirable? How can it be eliminated? (4 Marks)
(c) Enumerate various types of Portland cement. (5 Marks)
(d) Determine the temperature co-efficient of resistance of material used in a resistor if the resistance at 250C is 50 Ω and at 700C is 57.2 Ω. (5 Marks)
4(a) Describe the domain theory of magnetic materials. Explain also the experimental verification for the existence of domains in magnetic materials. (8 Marks)
(b) Discuss briefly about the characteristics of permalloys and soft magnetic ferrites. What is meant by cyclic magnetization and spontaneous magnetization? (8 Marks)
(c) In a certain transformer, the hysteresis loss is 0.9 Wb/m2 and the frequency 50 Hz. What would be the hysteresis loss if the maximum flux density were increased to 1.1 Wb/m2 and the frequency reduced to 40 Hz. Assume the hysteresis loss over this range  to be proportional to B1.7max . (4 Marks)
5(a) What do you understand by polymerization? What is the difference between addition-polymerisation and condensation-polymerisation? (6 Marks)
(b) What is the degree of polymerization of a polymer molecule? Give three examples of linear polymers. (5 Marks)
(c) What is a hybrid composite? Give important advantages of hybrid composites over normal fiber composites. (5 Marks)
(d) An applied strain of 0.4 produces an immediate stress of 10 MPa in a piece of rubber. Calculate the relaxation time for this process. What will be the stress after 90 days? (4 marks)
6(a) What is water-cement ratio? How does it affect the strength of concrete? (4 Marks)
(b) Explain the significance of testing the initial and final setting time of cement and how is it done? What is the effect of addition of gypsum on setting time? (6 Marks)
(c) What are the functions of springs? On which factors does the choice of material for springs depend? List various materials which are employed for producing springs. (7 Marks)
(d) The fineness modulus of coarse and fine aggregates are 6.0 and 3.0 respectively. If the mixture has a fineness modulus of 5.0, find the percentage of fine aggregate to be mixed with coarse aggregate. (3 Marks)
7(a) Explain the terms ‘thermal shock’ and ‘thermal shock resistance’. (4 Marks)
(b) What are the different types of coatings applied to prevent corrosion? Compare their advantages and disadvantages. (6 Marks)
(c) Explain the zone theory of solids. Discuss characteristics of conductors, semiconductors and insulating materials. (6 Marks)
(d) Calculate the diffusion coefficient for magnesium in aluminium at 5700C, given that D0 and Q are 1.2 × 104 m2/s and 131 kJ/mole respectively. (4 Marks)
8(a) State briefly the process of making a powder metallurgy product having improved properties. Discuss the advantages of powder metallurgy. (8 Marks)
(b) What effect will preheating have on the microstructure of the weld area in high carbon steel? (4 Marks)
(c) Explain with neat sketches thermit welding and metallic arc welding. (8 Marks)

Friday, 19 June 2015

Theory of elasticity -Model question paper for B.E/B.Tech Engineering

1(a) A semi- infinite elastic medium is subjected to a normal pressure of intensity ‘P’ distributed over a circular area of radius ‘a’ at x=0. Determine the stress distribution by using Fourier integral method. (8 Marks)
(b) A cantilever beam of rectangular cross-section 40 mm wide and 60 mm thick is 800 mm in length. It carries a load of 500 N at the free end. Determine the stresses in the cantilever at mid-length. (6 Marks)
(c) Determine the stress and displacement fields in an infinite medium due to equal and opposite point forces acting at different points along their common line of action. (6 Marks)
2(a) What are general solution to Biharmonic equation. (6 Marks)
(b) What is Winkler’s theory? Explain. (8 Marks)
(c) A circular disc of 8 cm diameter and 5 mm thick is subjected to diametral compression. If the applied load is 800 N, determine the stress distribution in the disc at the centre. (6 Marks)
3(a) An infinite plate contains an elliptical hole, with major and minor axes a and b. If the plate is under all round tension and the hole is unstressed, determine the hoop stress around the hole and show that the stress concentration factors at the ends of the major and minor axes are 2a/b and 2b/a respectively. (6 Marks)
(b) Explain St.Venant’s theory. (5 Marks)
(c) An elliptical shaft of semi axes a=0.05 m, b=0.025 m, and G=80 GPa is subjected to a twisting moment of 1200 π N.m. Determine the maximum shearing stress and the angle of twist per unit length. (4 Marks)
(d) Derive Bredt’s formula for the rate of twist in terms of the shear-stress distribution for the torsion of thin-walled sections. (5 Marks)
4(a) An 150 mm × 100 mm × 12 mm unequal angle bar is placed with the long leg vertical and used as a beam supported at each end, the span being 3 m. If load of 6500 N is placed at the mid length of the bar, determine the maximum stress due to bending. (6 Marks)
(b) Derive the generalized flexure formula. (5 Marks)
(c) A prismatic bar of 2a × 2b cross-section is bent by two equal and opposite couples. Determine the equations for the bent shape of the prismatic bar. (5 Marks)
(d) A point force of 500 N is applied normal to a semi-infinite solid. Determine the stress distribution at a depth of 50 mm and angular location of 150 with the line of action of the force. (4 Marks)
5(a) Describe membrane analogy for the bending of thin plates. How this analogy can be used to determine the deflection of a plate? (6 Marks)
(b) Derive Navier’s equations for the bending of a circular plate. What are the assumptions made? (10 Marks)
(c) A circular plate 50 mm diameter is clamped at the edge. Its deflection at the centre is limited to 1 mm when a pressure of 1 MPa is applied. Calculate the thickness of the plate and the maximum stress developed in it. E = 200 GPa, v=0.3. (4 Marks)
6(a) By neglecting bending stresses, derive the equations of equilibrium for shells of revolution. (8 Marks)
(b) A long circular pipe of radius 300 mm and wall thickness 10 mm is subjected to a uniform bending moment of 10 N-m and a shear force of 1600 N at one end. Determine the maximum deflection of the pipe. (4 Marks)
(c) What are different types of elastic foundations? Derive the differential equation for the elastic line of a beam resting on an elastic foundation. (8 Marks)
7(a) State and prove the Maxwell-Betti reciprocal theorem. (8 Marks)
(b) What are the various types of elements used for plane stress analysis. (4 Marks)
(c) What do you understand by interpolation function or shape function for an element? (4 Marks)
(d) A beam column of circular cross-section is 50 mm in diameter and 2 m long. It is simply supported at the ends and carries an axial compressive load of 3.5 kN. If a couple of 15 N-m is applied at the right end in the anti-clockwise direction, determine the deflection and maximum stress developed in the column at mid-span. Take E=2×105 N/mm2. (4 Marks)
8(a) Derive an expression for the deflection of a thin circular plate of radius ‘a’ heated on the lateral surface. (6 Marks)
(b) The temperature rise of a solid conductor of radius ‘b’ due to a uniform heat source is given by the formula T = λ (b2 - r2), where λ is a constant. If there are no external forces resisting longitudinal or radial expansion, determine the stress distribution in the conductor. (6 Marks)
(c) A 500 mm radius wheel supporting a 200 kN load rests on a rail 100 mm radius. The material of both is steel with E=2×103 N/mm2 and v=0.3. Determine the maximum contact pressure and the total contact area. (4 Marks)
(d) Distinguish between stress-concentration factor and strain-concentration factor. (4 Marks)

Material science and engineering- Model question paper for B.E/B.Tech Engineering

Tuesday, 16 June 2015

Fluid Mechanics and thermodynamics of turbomachinary- Model question paper for B.E/B.Tech Engineering

1(a) Write a note on the equation of continuity. (4 Marks)
(b) Explain the terms turbine polytropic efficiency and reheat factor. (4 Marks)
(c)  Describe with the aid of sketches, the relationship between geometry and specific speed for pumps. (8 Marks)
(d) A fan operating at 1750 rev/min at a volume flow rate of 4.25 m3/s develops a head of 153 mm measured on a water-filled U-tube manometer. It is required to build a larger, geometrically similar fan that will deliver the same head at the same efficiency as the existing fan but at a speed of 1440 rev/min. Calculate the volume flow rate of the larger fan. (4 Marks)
2(a) Write a note on cascade performance parameters. (6 Marks)
(b) Explain Mollier diagram for an impulse turbine stage. (6 Marks)
(c) Derive an approximate expression for the total-to-total efficiency of a turbine stage in terms of the enthalpy loss coefficients for the stator and rotor when the absolute velocities at inlet and outlet are not equal. (4 Marks)
(d) A two-dimensional compressor cascade is tested in air with an inlet stagnation pressure of 1 bar and an inlet stagnation temperature of 300 K. For an inlet Mach number of 0.75 and an inlet flow angle of 500, the exit flow angle is measured as 15.80. Determine the mass flow rate per unit frontal area. Assuming the flow is isentropic; calculate the exit Mach number and the static pressure ratio across the cascade. (4 Marks)
3(a) Explain the velocity diagrams for a compressor stage. (6 Marks)
(b) Derive an expression for the degree of reaction of an axial compressor stage in terms of the flow angles relative to the rotor and the flow coefficient. (6 Marks)
(c)  The rotational speeds of a four-bladed axial flow fan is 2900 rev/min. At the mean radius of 16.5 cm the rotor blades operate at CL=0.8 with CD=0.045. The inlet guide vanes produce a flow angle of 200 to the axial direction and the axial velocity through the stage is constant at 20 m/s. For the mean radius, determine
(i) the rotor relative flow angles, (ii) the stage efficiency, (iii) the rotor static pressure increase and (iv) the size of the blade chord needed for this duty. (8 Marks)
4(a) Prove that in a turbomachine, equal work is delivered at all radii and the total pressure losses across a row are uniform with radius. (8 Marks)
(b) Derive the radial equilibrium equation for an incompressible fluid flowing with axisymmetic swirl through an annular duct. (8 Marks)
(c) Gas leaves an untwisted turbine nozzle at an angle 450 to the axial direction and in radial equilibrium. Determine the axial velocity at a radius of 0.6 m when the axial velocity is 100 m/s at a radius of 0.3 m. (4 Marks)
5(a) Define slip factor. Write a note on slip factor correlations. (6 Marks)
(b) Distinguish between symmetric volute and overhung volute. (4 Marks)
(c) Using the performance chart given by Sovran and Klomp, determine the efficiency of a conical low speed diffuser to give maximum pressure recovery with a prescribed non-dimensional length of 8.0 and evaluate the included angle of the cone. (6 marks)
(d) A model low speed centrifugal compressor runs at 430 rpm and delivers 10 m3/s of air against pressure head of 60 mm of water. If the pump efficiency is estimated to be 80%, how much power is required to drive the compressor? (4 Marks)
6(a) Distinguish between Cantilever turbine and 900 IFR turbine. (4 Marks)
(b) Define spouting velocity. (3 Marks)
(c) Several decisions need to be made regarding the design of the rotor exit. Explain. (5 Marks)
(d) An IFR turbine is required with a power output of 300 kW driven by a supply of gas at a stagnation pressure of 222 kPa, at a stagnation temperature of 1100 K, and at a flow rate of 1.5 kg/s. The turbine selected by the engineer has 13 vanes and preliminary tests indicate it should have a total –to-static efficiency of 0.86. Based on the optimum efficiency design method sketch the appropriate velocity diagrams for the turbine and determine (i) the absolute and relative flow angles at rotor inlet, (ii) the overall pressure ratio and (iii) the rotor tip speed. ( 8 Marks)
7(a) With a neat figure, explain the working of Pelton turbine. (6 Marks)
(b) Write a note on effect of size on turbomachine efficiency. (4 marks)
(c) A model of Francis turbine is built to a scale of one fifth of full size and when tested it developed a power output of 3 kW under a head of 1.8 m of water, at a rotational speed of 360 rev/min and a flow rate of 0.215 m3/s. Estimate the speed, flow rate and power of the full-scale turbine when working under dynamically similar conditions with a head of 60 m of water. (6Marks)
(d) A model of a Kaplan turbine, built to a scale of 1/6 of the full scale prototype, develops an output of 5kW from a net head of 1.2 m of water at a rotational speed of 300 rev/min and a flow rate of 0.5 m3/s. Determine the efficiency of the model. (4 Marks)
8(a) What is the role of tower height in the design of horizontal axis wind turbine? (4 Marks)
(b) Determine the radii of the unmixed slipstream at the disc (R2) and far downstream of the disc (R3) compared with the radius far upstream (R1). (4 Marks)
(c) Explain Aileron control and blade pitch control. (6 Marks)
(d) A three-bladed HAWT with a rotor of 60 m diameter operates with a tip-seed ratio, J=5.5. At a radius of 25m, the blade chord is 1.5 m and the blade pitch angle, β = 2.50. Assuming negligible drag and using an iterative method of calculation, determine values for the axial and tangential induction factors a and a at that section. Assuming that CL is 0.1 × angle of incidence, what is the final value of the lift co-efficient? ( 6 Marks)

Computational fluid dynamics -Model question paper for B.E/B.Tech Engineering

1(a) Mention some advantages of Computational fluid dynamics. (5 Marks)
(b) Explain the use of Computational fluid dynamics in automotive engineering. (5 Marks)
(c) What details can Computational fluid dynamics capture in the simulation of hydro-cyclones, a process commonly used in the minerals industry? (6 Marks)
(d) What competitive edge can Computational fluid dynamics give to a cycling team? (4 Marks)
2 (a) How are commercial codes allowing Computational fluid dynamics analyses to be carried out with ease for the novice user? (5 Marks)
(b) What are the advantages of using X-Y plots? Give examples of what Computational fluid dynamics results X-Y plots can capture. (6 Marks)
(c) What type of boundary can be used for a computational boundary that represents an open physical boundary? (4 Marks)
(d) What is the meaning of a streamline? What advantages do they have over other plot types? (5 Marks)
3 (a) Obtain the general analytical solution for Laplace’s equation for a one-dimensional case. (8 Marks)
(b) The Reynolds number is a ratio of two fluid properties. What are they? (4 Marks)
(c) The use of direct numerical simulation-DNS remains a problem for engineering applications. Why? (4 Marks)
(d) What is the significance of the Prandtl number equaling to one in terms of entry lengths. (4 Marks)
4 (a) What is the Gaussian elimination method based on? Can this method be used to solve a system of nonlinear algebraic equations? (6 Marks)
(b) Where are the flow-field variables located in collocated grids? How is this different from the locations in a staggered grid? (6 Marks)
(c) What is the significance of integration of the governing equations over a control volume during the finite-volume discretization? (4 Marks)
(d) Why are higher order upwind schemes more favorable than the first order upwind scheme? (4 Marks)
5(a) What is the stability criteria produced by the Von Neumann analysis? (4 Marks)
(b) Discuss briefly how multigrid methods are employed to increase the computational efficiency in solving Computational fluid dynamics problems. (5 Marks)
(c) How is the concept of residual applied to describe the discretized equation of the system of transport equations? (5 Marks)
(d) What are discretization errors? What is the difference between a global error and a local error? (6 Marks)
6(a) What are the some of the difficulties that arise regarding programming of Computational fluid dynamics problems for an unstructured mesh? (6 Marks)
(b) What is the skewness of a mesh element? Why is it best to avoid highly skewed elements? (6 Marks)
(c)  Without experimental data for turbulent inlet profiles, what is the recommended method to consider turbulence effects? (4 Marks)
(d) Why do engineers prefer the Reynolds-averaged-based turbulence models such as the k-ε model over the complex LES model? (4 Marks)
7(a) What is the Eulerian description of a fluid motion? How dioes it differ from the Lagrangian description? (6 Marks)
(b) Explain how Computational fluid dynamics deal with heat transfer coupled with fluid flow. (8 Marks)
(c)  Computational fluid dynamics is well suited to analyze a wide range of shape options. Explain. (6 Marks)
8(a) What advanced techniques would be required to simulate airflow through the respiratory system into the lungs? What about pulsating blood flow through veins and arteries? (6 Marks)
(b) What is the immerse boundary method and how is this different from using a boundary fitted grid? (6 Marks)
(c) What is the difference in one-way coupling and two-way coupling in multiphase flows? (4 Marks)
(d) What difficulties arise from modeling a transient supersonic flow around an airfoil? (4 Marks)

Monday, 15 June 2015

Fluid Mechanics, Hydraulics And Hydraulic Machines -Model question paper for B.E/B.Tech Engineering

1(a) Write Newton's equation of viscosity. What do you understand by the Newtonian and Non-Newtonian fluids? (4 Marks)
(b) Explain the working of a single-tube manometer. What is the advantage of a single-tube manometer over an ordinary manometer. (6 Marks)
(c) What are the different modes of failure of a gravity dam? How would you compute the hydrostatic pressure when the upstream face is (a) vertical, (b) inclined and (c) curved? (5 Marks)
(d) A dock gate is to be reinforced with the three equal horizontal beams. If the water acts on one side only to a depth of 6m, find the positions of the beams, measured below the water, so that each will carry an equal load and give the load on each per meter run. (5 Marks)
2(a) Define the terms centre of buoyancy and metacentric height. (4 Marks)
(b) A cylindrical tank partly filled with a liquid is rotated at a constant angular velocity ω about its vertical axis. What form will the free surface assume? How will the pressure intensity vary along the bottom of the tank? (6 Marks)
(c) What is continuity equation? Derive the equation for one-dimensional incompressible flow. (6 Marks)
(d) At a sudden enlargement of a water line from 240 mm to 480 mm diameter pipe, the hydraulic gradient line rises by 10 mm. Estimate the rate of flow. (4 Marks)
3(a)What is the difference between a small and large orifice? (4 Marks)
(b) What is the difference between a sharp-crested weir and a broad-crested weir? (4 Marks)
(c) What is the difference between pipe flow and open channel flow? Derive Darcy-Weisbach equation for the loss of head due to friction in a pipe. (8 Marks)
(d) Find the discharge of water flowing through a pipe of 30 cm diameter placed in an inclined position where a venturimeter is inserted having a throat diameter of 15 cm. The difference of pressure between the main and the throat measured by the liquid of specific gravity 0.60 in an inverted U-tube which gives a reading of 30 cm. The loss of head between the main and the thtroat is 0.2 times the kinetic head of the pipe. (4 Marks)
4(a) Define the terms Celerity and Mach number. (4 Marks)
(b) State Buckingham's π-theorem. What is the advantage of Buckingham's π-theorem over Rayleigh's method of dimensional analysis. (6 Marks)
(c) Explain the difficulties in obtaining complete similitude in a ship model. How these difficulties are overcome? (6 Marks)
(d) The irrigation channel of trapezoidal section has the slide slopes 1 horizontal to 1 vertical. It has to carry 10 cumecs at a bed slope of 1 in 5000. Find the most economical section. Take Manning's N = 0.012. (4 Marks)
5(a) Find the kinematic viscosity in stokes of water whose specific gravity is 0.95 and viscosity 0.011 poise. (4 Marks)
(b) Show that the smooth pipe and rough pipe formulae for the coefficient of friction can be combined in one formula, and hence obtain the common formula. (8 Marks)
(c) What do you understand by separation of boundary layer? How it affects the flow pattern? Describe the methods to control separation. (4 Marks)
(d) An airfoil of 20 m span and 2 m chord has the lift and drag coefficients of 0.60 and 0.05 respectively for a certain angle of attack. Calculate the power required to drive the airfoil in horizontal flight at 360 km/hour. Also calculate the lift force. Take air density = 1.20 kg/cubic meter. (4 Marks)
6(a) What is the necessity of transitions in open channels? Describe various types of transitions used in practice. (6 Marks)
(b) A jet of water 2.5 cm in diameter strikes a symmetrical vane at the centre and gets deflected by 150 degrees. calculate the thrust on the vane if the velocity of the jet is 20 m/sec. (4 Marks)
(c) What is a draft tube? Derive an expression for the efficiency of a draft tube. (6 Marks)
(d) A wide rectangular channel carries a discharge of 3 cumecs per meter width on a slope of 1 in 1000. A  weir is constructed across the channel which increases the depth to 2 m. Calculate the distance from the weir to a point where the depth is 1.75 m. Use Bresse's method. C=45, N=0.025. (4 Marks)
7(a) Derive an expression for the specific speed in terms of power P, head H and revolutions per minute N. (8 Marks)
(b) Explain the reason for fitting large air vessels on the suction and delivery pipes of a reciprocating pump close to the cylinder. (4 Marks)
(c) Two geometrically similar pumps are run at the same speed of 1000 r.p.m. One pump has an impeller diameter of 0.3 m and lifts water at the rate of 20 lit/sec against a head of 15 m. Determine the head and impeller diameter of the other pump to deliver half the discharge. (4 Marks)
(d) Explain briefly the uses of the hydraulic accumulator. (4 Marks)
8(a) What is sediment? What are the tree types of sediments? Explain. (6 Marks)
(b) Obtain an expression for the stream function for a combined flow consisting of a uniform flow of 20 m/s parallel to the positive direction of the x-axis and a uniform flow of 10 m/s parallel to the positive direction of the y-axis. (6 Marks)
(c) What is a forebay? What are its uses? (4 Marks)
(d) For a hydropower plant, the design capacity is 1.23 × 105 kW. If the generated power is 10 × 104 kW, determine the efficiency of the plant. If the peak discharge is 1.60 times the normal discharge, determine the plant capacity. (4 Marks)

Advanced Microprocessors and Peripherals -Model question paper for B.E/B.Tech Engineering

1(a) Draw and discuss a typical maximum mode 8086 system. What is the use of a bus controller in maximum mode? (8 Marks)
(b) What are the functions of the clock generator IC 8284, in the 8086/8088 systems? (4 Marks)
(c) What is the difference between the jump and loop instructions? (4 Marks)
(d) Explain the addressing modes for control transfer instructions. (4 Marks)
2(a) Enlist the advantages of assembly language programming over machine language. (4 Marks)
(b) Write an ALP to change an already available ascending order byte string to descending order. (6 Marks)
(c) What is the role of stack in calling a subroutine and returning from the routine? (4 Marks)
(d) How do you set or clear the interrupt flag IF? What is its importance in the interrupt structure of 8086? (6 Marks)
3(a) Describe the procedure of interfacing static memories with a CPU. Bring out the differences between interfacing the memories with 8086 and 8088. (6 Marks)
(b) Design a one unit 14-segment alphanumeric display and write a program to display an alphanumeric character of which the code is in AX. (8 Marks)
(c) Using a typical 12-bit DAC generate a step waveform of duration 1sec, maximum voltage 3 volts and determine duration of each step suitably. (6 Marks)
4(a) Draw and discuss the asynchronous mode transmitter and receiver data formats of 8251. (6 Marks)
(b) Explain the significances of different bits of the control word register format of 8253. (4 Marks)
(c) What is a light pen? Explain its working principle. (4 Marks)
(d) Explain the different important timings required for operation of the CRTC  6845. Explain how they are obtained from the dot clock. (6 Marks)
5(a) What are the different types of exceptions which may be generated by 8087? (4 Marks)
(b) Write a program to calculate the nth power of an 8-bit hexadecimal number, where n is less than eight, using 8087 instructions. (8 Marks)
(c) What are the different interrupts available in 80286? (4 Marks)
(d) What do you mean by boundary testing instructions? What is their use? (4 Marks)
6(a) Explain the cache management unit of 80486. (4 Marks)
(b) Draw and discuss the register set of 80386 and explain a typical function of each of the registers in brief. (8 Marks)
(c) What is translation look aside buffer? How does it speed up the execution of the programs? (4 Marks)
(d) Explain the physical address formation in PVAM of 80386. (4 Marks)
7(a) Explain the features of Pentium-Pro architecture which support dynamic execution of instructions. (4 Marks)
(b) Discuss paging and virtual memory in brief with reference to P4. (6 Marks)
(c) Compare and contrast between RISC and CISC architecture. (6 Marks)
(d) Write a note on smelter controller hardware. (4 Marks)
8(a) Explain the design of a Microprocessor based pattern scanner system. (8 Marks)
(b) Discuss the addressing modes and the data types supported by 80196. (6 Marks)
(c) Discuss the advantages of microcontroller based systems over microprocessor based systems. (6 Marks)

Friday, 12 June 2015

Computer and Communication Networks -Model question paper for B.E/B.Tech Engineering

1(a) Explain two types of Packet-Switched Networks. (6 Marks)
(b) Suppose that virtual paths are set up between every pair of nodes in an ATM network. Explain why connection setup can be greatly simplified in this case. (4 Marks)
(c) Find the average clipping time for each burst of information in statistical TDMs. (6 Marks)
(d) Consider a time division multiplexer having a frame time of 26 μs. Each user channel has 6 bits, and each frame has 10 bits of overhead information. Assume that the transmission line carries 2 Mb/s of information. How many user channels can be accommodated on the line? (4 Marks)
2(a) Write a note on orthogonal frequency division multiplexing. (8 Marks)
(b) For a local area network using CSMA/CD, assume a 12 percent frame error rate owing to noise and errors resulting from collisions. Discuss how the throughput U could be affected. (8 Marks)
(c) Consider a 2 Mb/s satellite transmission link through which 800-bit frames are transmitted. The propagation time is 200 ms. Find the link efficiency, using the stop-and-wait protocol. (4 Marks)
3(a) Mention some applications of Mesh networks. (4 Marks)
(b) What is Congestion? Explain the method to perform Congestion control at network layer. (6 Marks)
(c)  Distinguish between flood routing and deflection routing. (4 Marks)
(d) Consider a cellular network with 128 cells and a cell radius r=3km. Let g be 420 traffic channels for a N=7-channel cluster system. Find the area of each hexagonal cell, total channel capacity and the distance between the centers of nearest neighbouring cochannel cells. (6 Marks)
4(a) What are the two most important forms of transportation in the TCP/IP network? Explain. (8 Marks)
(b) Find out about an IP address that is well known to you, such as that of your college or your work server. Set up an experiment in which you look up the domain name for this IP address. (6 Marks)
(c) Write a computer program to find the cipher text for a message, using DES to encrypt a 64-bit message, including all 0s with a 56-bit secret key consisting of 1010…10. Assume that a 1-bit rotation in the key process. (6 Marks)
5(a) Explain Non-Markovian and Self-Similar models of queueing systems. (6 Marks)
(b) In a nonpreemptive priority queueing scheme, a low-priority flow is guaranteed to receive 10% of the total bit rate s of the transmission link. How much better does this low-priority flow perform? What would be the impact on the performance of the high-priority flows? (4 Marks)
(c) What are the three types of blocking switch fabrics? (6 Marks)
(d) Compare the complexity of large-scale three-stage and five-stage clos switching systems, where the number of ports varies from 1000 to 2000 ports. (4 Marks)
6(a) Write a note on classification of optical switch elements. (4 Marks)
(b) To design an 8 x 8 optical router, we are comparing three different structures, each using, respectively, a crossbar switching network, a Spanke-Benes network, and an 8 x 8 directional coupler. Which structure offers the best overall cross-talk suppression? Which structure has the lowest overall average switching delay? (6 Marks)
(c) What is multicast backbone? Explain. (4 Marks)
(d) To optimize the routing delay in a sparse-mode PIM, find the optimal place for the rendezvous point. Give an example of a spanning tree, and justify your answer. (6 Marks)
7(a) What are virtual private networks? Explain the two types. (6 Marks)
(b) Consider an overlay network that consists of five connected nodes. Compare two methods for a peer-to-peer connection on top of the internet using a ring topology. (8 Marks)
(c) Assume that a normal-distributed source with zero mean and variance of 2 is to be transmitted via a channel that can provide a transmission capacity of 4 bits/each source output. What is the minimum mean-squared error achievable? What is the required transmission capacity per source output if the maximum tolerable distortion is 0.05? (6 Marks)
8(a) Write a note on Self-Similarity with Batch Arrival Models. (6 Marks)
(b) Compare table-driven and source-initiated routing algorithms in terms of (a) Speed of routing table updates and (b) Point-to-point routing when there is a sudden change in the network topology. (8 Marks)
(c) What are the three main blocks of the sensor node? Explain. (6 Marks)