Statistical Design and Quality

Garvin’s 8 Dimensions of Quality

1. Performance 2. Features 3. Reliability 4. Conformance 5. Durability 6. Serviceability 7. Aesthetics 8. Perceived Quality

What is performance quality?

How well a product performs its intended function and meets customer needs.

What is conformance quality?

How much a product meets established standards/specifications (e.g. safety).

What is dependability or reliability in the context of product quality?

The ability of a product or system to consistently achieve a performance result under specific operating conditions.

What does robust mean in the context of product quality?

Variabilities in input do not cause too much variability in output.

What is a “failure mode”?

A failure mode connects causes to observable effects when desired behaviour is not achieved.

5 types of noise

1. piece-to-piece 2. change over time 3. customer usage/misusage 4. external environment 5. system interaction

What is process quality?

How effectively or efficiently inputs are transformed into outputs while maintaining consistency, reducing waste, and delivering value to the customer.

What is an Error State?

A description of the behaviour - specifically, a behaviour that is not the intended output.

List the non-functional requirements relating to SRSAEIUFSRIP

Security, Reliability, Survivability, Availability, Efficiency, Integrity, Usability, Flexibility, Scalability, Reusability, Interportability, Portability

2 signs of instability in a process control chart

1. a point outside of the control limits 2. 8 points in a row on one side of the mean

KANO quality model 3 lines

1. fundamental requirements 2. exciting features 3. performance needs

Empirical rule for 1-sigma, 2-sigma, 3-sigma

68%, 95.45%, 99.73%

What is SIPOC? What does it stand for?

SIPOC is a six-sigma process mapping tool. It stands for Suppliers, Inputs, Process, Outputs, and Customers.

What is TIMWOOD? What does it stand for?

TIMWOOD is a six-sigma tool for identifying inefficiencies in a process. TIMWOOD stands for Transport, Inventory, Motion, Waiting, Overproduction, Overprocessing, Defects.

4 DMAIC define tools?

1. C2QT 2. Is/Is-not 3. QFD 4. FMEA

What is C2QT?

A tool for identifying the technical requirements for performance needs / attributes. It turns the customer voice into critical-to-quality metrics.

What is Is/Is-Not?

A tool to help you narrow the problem definition using 4 Ws + How.

What is QFD?

Tool that relates customer requirements with engineering requirements. Shows conflicting quality attributes very well.

What is FMEA? What should its columns be?

FMEA is failure mode effect and analysis. Columns are 1. Step/input 2. Potential failure mode 3. Potential failure effects 4. Severity of failure effect (1-10) 5. Potential cause of failure 6. Frequency of failure cause occurance 7. Controls 8. Ease of detection (1-10)

How to calculate FMEA RPN?

Severity x Likelihood x Detection

What is the Fishbone diagram? What are its 6 bones?

Fishbone is a tool used to find potential causes of failure in different areas. Its bones are Methods, Machines, Materials, Measurement, People, and Environment.