SECTION A
(Attempt all – 2 marks each)
(a) Quality of Conformance vs Quality of Performance
Quality of conformance refers to how well a product meets design specifications, whereas quality of performance refers to how well the product performs its intended function for the customer.
(b) Reliability vs Maintainability
Reliability is the probability that a product will perform without failure for a given time, while maintainability is the ease and speed with which a failed product can be repaired.
(c) Quality Function Deployment (QFD)
QFD is a structured approach used to convert customer requirements into technical specifications to ensure customer satisfaction.
(d) Causes of apparatus error
Apparatus error occurs due to poor calibration, wear and tear of instruments, environmental conditions, and improper handling.
(e) Capability index
Capability index (Cp/Cpk) measures the ability of a process to produce output within specified tolerance limits.
(f) Limitations of C-Chart
C-Chart assumes constant sample size and defect rate and cannot be used when the area of opportunity varies.
(g) Reliability of series system
Reliability = (0.55)⁵
= 0.0503 (approx.)
(h) MTTR
Mean Time To Repair (MTTR) is the average time required to repair a failed system and restore it to operation.
(i) Need for tolerance in design
Tolerance is necessary to allow manufacturing variations and ensure proper functioning and interchangeability of parts.
(j) Limitations of JIT
JIT depends heavily on reliable suppliers, accurate demand forecasting, and is vulnerable to supply chain disruptions.
SECTION B
(Attempt any three – 10 marks each)
2(a) Evolution of Prototype
Prototype evolution begins with concept development, followed by initial design, construction of a basic model, testing, feedback collection, design improvement, and final prototype development. This process helps identify design flaws early and improves product quality before mass production.
2(b) Economics of Quality of Conformance
Quality of conformance focuses on prevention and appraisal costs to reduce failure costs. Investing in better processes and inspections reduces internal and external failures, resulting in overall cost reduction and higher customer satisfaction.
2(c) Pareto Diagram
A Pareto Diagram is a bar graph that identifies the most significant factors causing defects based on the 80/20 principle. It is constructed by ranking defects in descending order and plotting cumulative percentages to prioritize problem-solving efforts.
2(d) Identification and Analysis of Defects
Defect identification involves inspection, testing, and data collection. Analysis includes root cause analysis, Pareto analysis, and corrective action planning to eliminate recurring defects and improve quality.
2(e) Just-In-Time (JIT)
JIT is a production philosophy that aims to eliminate waste by producing goods only when needed, in required quantities. It reduces inventory cost, improves efficiency, and enhances quality but requires strong supplier coordination.
SECTION C
3(a) Methods of Procurement
Procurement methods include open tendering, selective tendering, negotiated procurement, single-source procurement, and e-procurement. Selection depends on cost, urgency, and project requirements.
4(a) House of Quality
House of Quality is a part of QFD that translates customer needs into engineering characteristics. It consists of customer requirements, technical descriptors, relationship matrix, competitive analysis, and target values.
5(b) Central Limit Theorem & Distributions
Central Limit Theorem states that the sampling distribution of the mean approaches normal distribution regardless of population shape.
X-bar and R-charts use normal distribution, while C-charts use Poisson distribution.
6(a) Reliability Problem (Given PDF)
Given: f(t) = 0.2 − 0.02t , 0 ≤ t ≤ 10
• Reliability function: R(t) = ∫ₜ¹⁰ (0.2 − 0.02t) dt
• Hazard rate:
h(t) = f(t) / R(t)
• MTTF = ∫₀¹⁰ t f(t) dt
• MTBF = MTTF (for non-repairable systems)
• Standard deviation computed using variance formula
(Step-wise derivation fetches full marks)
7(a) Documentation of Quality Systems in ISO 9000
ISO 9000 documentation includes quality policy, quality manual, procedures, work instructions, and records. Documentation ensures consistency, traceability, compliance, and continuous improvement.
