Bachelors Level/Second Year/Fourth Semester/Science bit/fourth semester/operations research/syllabus wise questions

Bachelors In Information Technology

Institute of Science and Technology, TU

Operations Research (ORS255)

Year Asked: 2081, syllabus wise question

Decision Theory
1.
A cloud services provider buys data storage at Rs. 20 per GB and sells it to clients at Rs. 25 per GB. Any unsold storage capacity is wasted. The daily demand for storage has the following probability distribution. If each day's demand is independent of the previous day, using the marginal analysis approach calculate the required measures. (a) Calculate the maximum expected profit. (b) Find the expected profit with perfect information (EPPI). (c) Compute the expected value of perfect information (EVPI). (d) What will be the maximum amount the cloud provider would be willing to pay for perfect and reliable information?
Demand  (GB)46485052545658606264Probability0.010.030.060.100.200.250.150.100.050.05\begin{array}{|c|cccccccccc|}\hline Demand\;(GB) & 46 & 48 & 50 & 52 & 54 & 56 & 58 & 60 & 62 & 64 \\ \hline Probability & 0.01 & 0.03 & 0.06 & 0.10 & 0.20 & 0.25 & 0.15 & 0.10 & 0.05 & 0.05 \\ \hline \end{array}
[10]
Introduction
1.
What are the applications of operations research in different fields? [5]
Networking Analysis
1.
The following activities must be completed to complete the project. Determine the critical path and time duration of the project.
ActivityPredecessorTime  (in  a  week)A3B8CA,B4DB2EA1FC7GE,F5HD,F6IG,H8JI9\begin{array}{|c|cc|}\hline Activity & Predecessor & Time\;(in\;a\;week) \\ \hline A & - & 3 \\ \hline B & - & 8 \\ \hline C & A,B & 4 \\ \hline D & B & 2 \\ \hline E & A & 1 \\ \hline F & C & 7 \\ \hline G & E,F & 5 \\ \hline H & D,F & 6 \\ \hline I & G,H & 8 \\ \hline J & I & 9 \\ \hline \end{array}
[5]
2.
A project consists of nine activities whose time estimates (in weeks) and other characteristics are given below. What is the expected project completion time and its variance?
ActivitiesABCDEFGHIPreceding  activitiesAAB,DB,DC,FEOptimistic  time2662118394Most  likely  time46125141061510Pessimistic  time66248231292716\begin{array}{|c|ccccccccc|}\hline Activities & A & B & C & D & E & F & G & H & I \\ \hline Preceding\;activities & - & - & - & A & A & B,D & B,D & C,F & E \\ \hline Optimistic\;time & 2 & 6 & 6 & 2 & 11 & 8 & 3 & 9 & 4 \\ \hline Most\;likely\;time & 4 & 6 & 12 & 5 & 14 & 10 & 6 & 15 & 10 \\ \hline Pessimistic\;time & 6 & 6 & 24 & 8 & 23 & 12 & 9 & 27 & 16 \\ \hline \end{array}
[5]
Optimization(Linear Programming I: Formulation and Graphic Solution), (Linear Programming II: Simplex Method), Transportation problem, Assignment problem
1.
Find the optimum solution of the given LPP by using the simplex method.
Min  Z=20A+10BMin\; Z = 20A + 10B
Subject  to:Subject\;to:
A+2B40A + 2B \le 40
4A+3B604A + 3B \ge 60
3A+B303A + B \ge 30
A,B0A, B \ge 0
[10]
2.
Obtain the minimum transportation cost for the following transportation problem.
Destination/SourceS1S2S3Units  DemandedD1121610200D2151210200D311121250Units  Available200150100450\begin{array}{|c|ccc|c|}\hline Destination/Source & S1 & S2 & S3 & Units\;Demanded \\ \hline D1 & 12 & 16 & 10 & 200 \\ \hline D2 & 15 & 12 & 10 & 200 \\ \hline D3 & 11 & 12 & 12 & 50 \\ \hline Units\;Available & 200 & 150 & 100 & 450 \\ \hline \end{array}
[10]
3.
A software company wants to assign its technical support agents to different regions to maximize customer satisfaction. The company has four agents, each with varying effectiveness in different regions. The table below shows the expected satisfaction score if each agent is assigned to a specific region. Use the Hungarian method to assign each technical support agent to a region in a way that maximizes overall customer satisfaction.
Regions/AgentsSandipSanjayShankarSubhashKathmandu140146148136Biratnagar148132136129Janakpur149135141138Butwal130146149144\begin{array}{|c|cccc|}\hline Regions/Agents & Sandip & Sanjay & Shankar & Subhash \\ \hline Kathmandu & 140 & 146 & 148 & 136 \\ \hline Biratnagar & 148 & 132 & 136 & 129 \\ \hline Janakpur & 149 & 135 & 141 & 138 \\ \hline Butwal & 130 & 146 & 149 & 144 \\ \hline \end{array}
[5]
4.
ABC Manufacturing Company produces three products: Tables, Chairs, and Desks. These products require processing through three departments: Cutting, Assembly, and Painting. These three departments have limited working time to 300 hours, 450 hours, and 200 hours per week respectively. Each table requires 4 hours for cutting, 5 hours for assembly, and 1 hour for painting and contributes Rs. 1000 to profit. Each chair requires 3 hours for cutting, 4 hours for assembly, and 1 hour for painting and contributes Rs. 800 to profit. Each desk requires 2 hours for cutting, 3 hours for assembly, and 2 hours for painting and contributes Rs. 1200 to profit. To maintain balance, the total production of all three products must not exceed 150 units per week. Formulate objective (profit) function and constraints for this LPP. [5]
5.
Explain the algorithm of the Modified Distribution (MODI) method for testing the optimality of the transportation problem. [5]
6.
Write short notes on: (a) Vogel's Approximation Method (VAM) (b) Dominance rule of game theory [0+2.5+2.5]
Queuing Models
1.
A bank operates a single-channel queuing system with customers arriving at a rate of 6 per hour and each customer being served at an average rate of 8 per hour. Calculate (a) the average number of customers in the system and (b) the average waiting time.
λ=6  per  hour\lambda = 6\;per\;hour
μ=8  per  hour\mu = 8\;per\;hour
[5]
Theory of Games
1.
The following table gives a payoff in millions in the competitive situation between telecom companies ABC and XYZ. Determine the optimal strategies for each company and find the game value.
ABCs  Strategies/XYZs  StrategiesNo  advertisingMedium  advertisingHigh  advertisingNo  advertising504028Medium  advertising705045High  advertising755250\begin{array}{|c|ccc|}\hline ABC's\;Strategies/XYZ's\;Strategies & No\;advertising & Medium\;advertising & High\;advertising \\ \hline No\;advertising & 50 & 40 & 28 \\ \hline Medium\;advertising & 70 & 50 & 45 \\ \hline High\;advertising & 75 & 52 & 50 \\ \hline \end{array}
[5]