(SEM V) THEORY EXAMINATION 2023-24 INDUSTRIAL ENGINEERING

Course: B.Tech (Mechanical Engineering)

Semester: V

Subject Code: KME503

Subject Title: Industrial Engineering

Maximum Marks: 100

Duration: 3 Hours

Paper Format:

Section A: Short conceptual questions — 20 marks

Section B: Descriptive questions — 30 marks

Section C: Analytical and numerical problems — 50 marks

SECTION A — Short Answer Questions (10 × 2 = 20 Marks)

Students must attempt all questions briefly. These test theoretical definitions and key concepts in Industrial Engineering:

Define Productivity and explain how it is measured.

Productivity = Output / Input.

It can be measured as labor productivity, machine productivity, or overall productivity.

Explain briefly:

(i) Group Technology: Classifying parts into families with similar manufacturing processes.

(ii) Process Planning: Determining the sequence of operations and tools needed for production.

How is Forecasting different from Prediction?

Forecasting is based on data and models; prediction may rely on judgment or intuition.

Define:

(i) Crashing: Reducing project duration by allocating extra resources.

(ii) Dummy Activity: A zero-time activity used in network diagrams to maintain logic.

What is the Breakeven Point?

The production level where total cost equals total revenue; no profit, no loss.

Explain “Depreciation.”

The decrease in value of assets over time due to wear and tear or obsolescence.

What is Motion Study?

It involves analyzing work motions to improve efficiency and eliminate unnecessary movements.

Purpose of Work Sampling:

To determine the proportion of time spent on various tasks through random observation.

Why is Simulation Needed?

It helps model complex systems for decision-making without disrupting actual operations.

What do you mean by Assignment?

A linear programming technique used to assign tasks to resources at minimum cost or time.

SECTION B — Descriptive Questions (3 × 10 = 30 Marks)

Attempt any three of the following:

Define Productivity.

Explain types of production systems:

Job Production: Single products, low volume (e.g., shipbuilding).

Batch Production: Limited quantities in batches (e.g., bakery).

Mass Production: High volume, continuous production (e.g., automobiles).

Why is Production Planning and Control (PPC) needed?

Ensures material availability, reduces idle time, balances load, and meets delivery schedules.

Importance of ABC Analysis in Inventory Control:

A items: High value, low quantity — strict control.           B items: Moderate control.

C items: Low value, bulk quantity — simple control.

Taylor’s Scientific Management and Gilbreth’s Contribution:

Taylor: Time study, standardization, differential piece rate system.

Frank & Lillian Gilbreth: Motion study, fatigue study, development of therbligs.

Unbalanced Transportation Problem:

Occurs when total supply ≠ total demand.           Balanced by adding a dummy row or column.

SECTION C — Long / Analytical Questions (5 × 10 = 50 Marks)

Each question carries 10 marks. Attempt one part from each question (Q3–Q7).

Q3. Productivity & Material Handling

(a) A company manufactures 24,000 components/month using 100 workers in 8-hour shifts. It must produce 6,000 more using 20, 25, or 30 new workers.
→ Compare productivity (Output/Input) in each case to determine the most efficient staffing.

(b) Material Handling Equipment:

Selection principles include: flexibility, cost efficiency, load capacity, safety, and space utilization.

Q4. JIT & Network Analysis

(a) Just-In-Time (JIT):

Produces only what is needed, when it is needed.

Improves productivity by reducing waste, inventory, and lead time.

(b) PERT / CPM Network Problem:

Given activity data:

Tasks:

Find expected time te=(to+4tm+tp)/6t_e = (t_o + 4t_m + t_p)/6te​=(to​+4tm​+tp​)/6.

Find variance σ2=((tp−to)/6)2σ^2 = ((t_p - t_o)/6)^2σ2=((tp​−to​)/6)2.

Draw the network, calculate EST, LFT, slack, and critical path
 

Q5. Queuing & Materials Management

(a) Queuing Problem:

Arrival rate λ=30/hrλ = 30/hrλ=30/hr, Service time = 100 sec (µ = 36/hr).

Use M/M/1 model:

• Wq=λµ(µ−λ),Lq=λWqW_q = \frac{λ}{µ(µ - λ)}, \quad L_q = λW_qWq​=µ(µ−λ)λ​,Lq​=λWq​

Find waiting time and discuss customer behavior (balking, reneging).

(b) VED Analysis:

V (Vital), E (Essential), D (Desirable) items categorized by criticality to operation.

Helps prioritize spare parts management.

Q6. Work Study & Ergonomics

(a) Work Study and Measurement:

Combines method study and time study to identify best work methods and standard times.

Improves productivity through better planning, training, and layout optimization.

(b) Ergonomics and Motion Economy:

Ensures workplace design minimizes fatigue and enhances safety.

Principles: proper height, reach limits, use of both hands, and rhythm in motion.

Q7. Operations Research & Transportation

(a) Linear Programming (LP) — Simplex Method:

Minimize Z=3x+2yZ = 3x + 2yZ=3x+2y
Subject to:

• x+y≥4,x−y≤2,x,y≥0x + y ≥ 4, \quad x - y ≤ 2, \quad x, y ≥ 0x+y≥4,x−y≤2,x,y≥0

Solve using simplex method to find feasible region and optimal point.

(b) Transportation Problem (NWCM Method):

Given cost table:

Use North-West Corner Method (NWCM) for initial solution and check optimality using u–v method or MODI technique

Key Concepts Covered

Productivity measurement & production systems         Forecasting, planning, and control

Work study, motion study, and ergonomics                  Inventory & materials management (ABC, VED)

Project management (PERT, CPM)                                 Queuing theory and simulation

Operations research techniques (LP, transportation, assignment)