Computer Engineering



Okon, Walt, Computer Engineering - Comparison of QFD, Six Sigma, and ISO 9000, www.waltokon.com, 04 October 2002
QFD  Quality Function Deployment – This is also known as the “House Of Quality”.  The QFD is a tool or model to get you from the “Voice of the Customer” to the technical design specification.  It provides the ability to translate the Customer Requirements into measurable design targets.  It is important note that the QFD method can be applied to the entire problem/requirement element and/or any subproblem/ requirement subelement.

Basic Process:
For the QFD basic process there are six processes in the model that need to be completed.  They are:  1. Identifying the Customer(s) and listen to their needs and their requirements; 2. Determining Customer Requirements and defining them ( this is often done in the form of a System Engineering Architecture) [2]; 3. Prioritizing the Requirements in a consistent way and providing a means for the customer to validate their requirements; 4. Competition Benchmarking of what is considered the “best of breed”;  5. Translating the Customer Requirements into Measurable Engineering Requirements in a way that is consistent and objective; and finally 6. Setting Engineering Targets for Design which becomes specifications. [3]

Approach to Measurement:
The QFD approach to measurement is to develop engineering requirements (often called
design specifications) that are measurable for use in evaluating the proposed designs.  This set of defined specifications is the standards or become the standards by which the engineer can accomplish the system design.  This allows the engineer to design in measurement data by which analysis can take place.  Thus the customer requirements are transformed into
engineering requirements.  In this same process, the design engineer makes sure that the engineering requirements are measurable.

Emphasis on Customer Satisfaction
The whole purpose of QFD is to promote integration of organizational functions to facilitate responsiveness to customer requirements. [1]  Thus the structured relationships that are developed by the multifunctional teams all with the objective to ensure that the information gathered about the customer requirements can be best documented and used in the design of the system meeting the customer requirements.  The satisfaction of the customer and the customer needs is the primary emphasis of the model.  
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Six Sigma
Six Sigma is a multi faceted approach to process improvement, reduced cost, and increased profits through customer satisfaction. [5]   Six Sigma simply means a measure of quality that strives for near perfection. The statistical implications of a Six Sigma program go well beyond the qualitative eradication of customer perceptible defects. It is a methodology that is rooted in mathematics and statistics with the objective of Six Sigma Quality to reduce process output variation so that ±six standard deviations lie between the mean and the nearest specification limit.  3.4 or fewer defective parts per million.  [4]

Basic Process
The Six Sigma methodology, consist of the steps Define, Measure, Analyze, Improve, and Control.  The primary goal of Six Sigma process is to improve customer satisfaction, and profitability, by reducing and eliminating defects.  So the concentration is on elimination of defects in each part of the process.  Defects can be related to customer satisfaction in the form of high product quality, schedule adherence, and cost minimization.  Taguchi Loss Function, which shows increasing defects leads to increased
customer dissatisfaction and financial loss.  Common Six Sigma measurement includes defect rates, sigma level, process capability indices, defects per unit, and yield.
Define, Measure, Analyze, Improve and Control (DMAIC) is the basic Six Sigma  process for continued improvement.  It is systematic, scientific and fact based. This closed-loop process eliminates unproductive steps, often focuses on new measurements, and applies technology for improvement.

Approach to Measurement
The approach to measurement is the key to the Six Sigma model.  The total approach is a statistical drive to define each part of the process in relation to defective parts.  Defect Reduction = process improvement + customer satisfaction.  Six Sigma is the disciplined application of statistical problem-solving tools that show you where wasteful costs are and points you toward precise steps to take for improvement.

The Six Sigma can be viewed as a set of tools that apply a refined methodology of measurement and discovery to gain a comprehensive understanding of performance and key variables affecting the quality of a company’s products and services. [6]  The tools/process model represents the peak of quality of a particular process  —  it is the virtual elimination of defects from every product and process within an organization.  The measurement is to define as sigma increases, customer satisfaction goes up while at the same time production cycle time goes down and costs goes down.
Six Sigma Quality Tools can be defined and used in terms related to quality. Below are the key tools. [7]
Control Chart – Monitors variance in a process over time and alerts the business to unexpected variance which may cause defects.
Defect Measurement – Accounting for the number or frequency of defects that cause lapses in product or service quality.
Pareto Diagram – Focuses on efforts or the problems that have the greatest potential for improvement by showing relative frequency and/or size in a descending bar graph. Based on the proven Pareto principle: 20% of the sources cause 80% of any problems.
Process Mapping – Illustrated description of how things get done, which enables participants to visualize an entire process and identify areas of strength and weaknesses. It helps reduce cycle time and defects while recognizing the value of individual contributions.
Root Cause Analysis – Study of original reason for nonconformance with a process. When the root cause is removed or corrected, the nonconformance will be eliminated.
Statistical Process Control – The application of statistical methods to analyze data, study and monitor process capability and performance.
Tree Diagram – Graphically shows any broad goal broken into different levels of detailed actions. It encourages team members to expand their thinking when creating solutions.

Emphasis on Customer Satisfaction
The emphasis on customer satisfaction is in relation to defects as the prim concern.  The customer is not the prime once the customer requirement is defined.  The concern is on reduction of defects and process improvement.
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ISO 9000 – International Standards Organization

The ISO 9000 Standards are the most comprehensive standards quality assurance and management standards.   The International Organization for Standardization (ISO) is a worldwide federation of national standards bodies from more than 140 countries, one from each country.  It is a non-governmental organization established in 1947.  Its mission is to promote the development of standardization and related activities in the world with a view to facilitating the international exchange of goods and services, and to developing cooperation in the spheres of intellectual, scientific, technological and economic activity.  ISO's work results in international agreements which are published as International Standards.  These Standards are documented agreements containing technical specifications or other precise criteria to be used consistently as rules, guidelines, or definitions of characteristics, to ensure that materials, products, processes and services are fit for their purpose.
ISO 9000 is primarily concerned with "quality management".  The standardized definition of "quality" in ISO 9000 refers to features and functions of a product (or service) which are required by the customer. "Quality management" means what the organization does to ensure that its products conform to the customer's requirements.
ISO 9000 defines Quality management principles.  It introduces the eight quality management principles on which the quality management system standards of the revised ISO 9000 series are based. These principles can be used by senior management as a framework to guide their organizations towards improved performance. The principles are derived from the collective experience and knowledge of experts.  ISO 9000 gives the standardized descriptions of the principles. In addition, it provides examples of the benefits derived from their use and of actions that managers typically take in applying the principles to improve their organizations' performance.
•    Principle 1 Customer focus
•    Principle 2 Leadership
•    Principle 3 Involvement of people
•    Principle 4 Process approach
•    Principle 5 System approach to management
•    Principle 6 Continual improvement
•    Principle 7 Factual approach to decision making
•    Principle 8 Mutually beneficial supplier relationships


Basic Process
The ISO 9000 Management system refers to what the organizations can do to manage its processes, or activities. Organizations need to write down and formalize procedures, instructions, forms or records in order to manage processes. These help ensure that everyone is not just "doing his or her thing", and that there is a minimum of order in the way the organization goes about its business, so that time, money and other resources are utilized efficiently.  Organization have to systemizing their processes. This ensures that critical actions are not missed and that everyone is clear about who is responsible for doing what, when, how, why and where.  ISO 9000 Management system standards provide the organization with a model to setup and operating its management system.  The organizational management system which it follows (the model) is built on a firm foundation of state-of-the-art practices.

 The figure shows that the senior leadership must lead and be involved to the point that the management system is their responsibility and they must infuse it throughout the organization.[8]   It is the senior leader that must demonstrate leadership and be visible, define the processes and the leadership to improve them, and empower the people who really know the system to do the improvement.  This will result in a “Quality management System”  which will result in a “Product Line Process” and deliver a “Quality Product.”

Approach to Measurement
The approach to measurement in the ISO 9000 is in relationship to Assessments, Audits and Conformance of the ISO 9000.  This is to say that the eight principles to improve their organizations' performance ( Customer focus ,  Leadership,  Involvement of people,  Process approach ,  System approach to management ,  Continual improvement, Factual approach to decision making, and Mutually beneficial supplier relationships) must be instutionalize in such a way that they can be measured and assessed. This will provide the ability to stand up under Audits.  The Audits in turn is the measurement and the results validate the management, processes and products.  It assures the customer that the developer can provide quality products and services.
There are four people or actors involved in auditing efforts:
1. the auditee, or the organization being audited;
2. the auditor, or group that does the auditing;
3. the customers of the organization or supplier; and
4. the client or customer for the audit.


There are three types of assessment, audit, or verification that may be used to indicate conformance with standards in general and ISO 9000 in particular. 

1. First-party assessment, or internal assessment, is comprised of an audit by
the supplier or producer organization, conducted against the appropriate
standard. This self appraisal may result in a standard conformance certificate.

2. Second-party assessment, or external assessment, is an audit performed by
the end user or customer as the client for an audit of the supplier organization.

3. Third-party assessment, or extrinsic assessment, is generally performed by
an auditor who may be certified or otherwise formally qualified for this purpose,
and who is not contracted for by either the organization (auditee) or its
customers. Thus, the auditor is independent of the auditee and its customers.

Configuration Management as it related to the ISO 9000 Approach to Measurement
Configuration management is a tool to ensure that processes are implemented correctly and a controlled.  There is the sound need for 'configuration management' of the efforts such that it is possible to associate a defined structure with the overall engineering effort.  This does allow for the effortless management of potential changes in the content of the system as it evolves in time.  This supports the incremental or evolutionary approach to system development and engineering.  The great advantage is that this would allow the system to be produced in phases and with processes that in themselves can be independently managed, controlled, and improved with the assurance that changes that made at some phase in development do not materially influence that part of the effort that has been already completed.  Another major advantage is that the greatest benefit to the system will be its integration ability across system modules to enable full configuration and integration.

Without good Configuration Management (CM) interactions, and their major advantages and significance, may be not fully realized by system developers.  Good CM will enable the system to be developed in an iterative manner where each additional sub-system is designed to serve a particular purpose and is easily integrated into the set of existing sub-systems.  This eliminates the need for rework on the part of individual sub-system developers that might well be needed if good configuration control is not maintained.

Good CM leads to the definition of needed sub-systems and interfaces such as to
provide guides and maps. Good CM leads to management of risks.  Thus, good CM will assist greatly in the timely production of a well structured and high quality product.

Emphasis on Customer Satisfaction

With the ISO 9000 there are several objectives where Customer Satisfaction is enhanced by the implementation of the ISO 9000 and the quality audits that can be used to assess the improvement with the resulting quality.
The audits deliver customer satisfaction because they:
1. to evaluate the efficiency and effectiveness of an organizations quality system;
2. to identify quality documentation difficulties;
3. to detect, diagnose and determine corrective actions for identified defects in the quality system;
4. to increase organizational understanding of quality issues;
5. to allow an organization to become registered as being in compliance with ISO 9000     6. to meet regulatory agency requirements; and
7. to determine conformance or nonconformance to a specific set of customer requirements such as to lead to appropriate certification levels or suppliers.
 

Executive Summary:


Our task was to compare QFD  Quality Function Deployment, Six Sigma, and ISO 9000.

QFD is a tool to get you from the Customer Requirement to the technical design specification.  It provides the ability to translate the Customer Requirements into measurable design targets.  Key is  QFD method can be applied to the entire problem/requirement element and/or any subproblem/ requirement subelement.  Everything is given a measured standard to be design to in order to achieve customer satisfaction.

Six Sigma is a multi faceted approach to process improvement, reduced cost, and increased profits through customer satisfaction. [5]   Six Sigma simply means a measure of quality that strives for near perfection. The statistical implications of a Six Sigma program go well beyond the qualitative eradication of customer perceptible defects. It is a methodology that is rooted in mathematics and statistics with the objective of Six Sigma Quality to reduce process output variation so that ±six standard deviations lie between the mean and the nearest specification limit.  3.4 or fewer defective parts per million.  Everything is given a measured to reduce the defects to achieve customer satisfaction.

ISO 9000 defines Quality management by eight quality management principles on which the quality management systems are based. These principles are a framework to guide their organizations towards improved performance and consist of  performance in relation to: Customer focus ,  Leadership,  Involvement of people,  Process approach ,  System approach to management ,  Continual improvement, Factual approach to decision making, and Mutually beneficial supplier relationships.  Every process and/or management ability is defined and implemented to improve processes to achieve customer satisfaction.
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References:

[1] .  Sage, Andrew P., Systems Management For Information Technology and Software Engineering, John Wily & Sons, New York, 1995, Page 190.

[2] .  Sage, Andrew P., Systems Management For Information Technology and Software Engineering, John Wily & Sons, New York, 1995, Page 191.

[3]   Patterson, F.G. Jr., PhD.  Organizational Culture, Lecture October 30, 2002, School of Information and Technology, George mason University, USA, Page 12.

[4]  Six Sigma, Statistical Six Sigma Definition, SigmaPro® Inc. http://www.isixsigma.com/library/content/c010101a.asp

[5]   Patterson, F.G. Jr., PhD.  Organizational Culture, Lecture October 30, 2002, School of Information and Technology, George mason University, USA, Page 09.

[6]  Six Sigma Consultants' Inc. Six Sigma Defined, http://www.dosixsigma.com/sixsigmadefinition.htm

[7]  GE,  Quality Approaches and Models,  http://www.ge.com/sixsigma/glossary.html

[8].  Sage, Andrew P., SYST 513: Strategic Quality Assurance and Management lecture Notes, School of Information Technology and Engineering, George Mason University
October 2002, Page 47.

[9].  Sage, Andrew P., SYST 513: Strategic Quality Assurance and Management lecture Notes, School of Information Technology and Engineering, George Mason University
October 2002, Page 47.
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