SQA

Improvement of EPC Software Maintenance with Six Sigma (1) 

                                                                                                                    by Isaac D. Mao

1. Introduction

A company is a leading provider of EPC applications. However, with the recent large amount of requests for enhancement/customization/maintenance from clients, some major problems were encountered as below:

• About 35% of maintenance projects could not meet customer expectations.
• Rework rates of the customization features/components reach as high as 30%.
• The cost of software testing has been increased by 30%.

 The goals of our 6-sigma project are reduce the rework rates, the time overrun and the cost of quality (COQ) with 6-sigma DMAIC methodology:

1. The problem is defined as the high customer dissatisfaction rate that should be decreased.
2. We will select proper metrics to measure the process.
3. We will analyze the possible causes from which the selected metrics might be resulted.
4. Suggested improvement would be given after analyzing and screening potential causes.
5. The control measures would be implemented to evaluate and ensure the improvements.

The 6-sigma project will use the following tools:

Phase	Tools
Define	Project charter, SIPOC,CTQ, VOC tools (survey)
Measure	Measurement systems analysis (MSA), Process capability
Analyze	Cause-and-effect diagram, ANOVA, Process Mapping
Improve	Brainstorming, Financial analysis
Control	Control Chart, ISO9000

2. Define Phase

2.1 High Level Process Map (SIPOC)

We map the company's current process with a SIPOC diagram shown in Figure 1, so that we can quickly define, document, analyze, prioritize and recommend solutions.


                           Figure 1 SIPOC of the Process

2.2 Critical to Quality (CTQ)

CTQs are the key measurable characteristics of a product or process whose performance standards or specification limits must be met in order to satisfy the customer. They align improvement or design efforts with customer requirements. Our team will focus on the existing process and activities between the customers. Figure 2 is a result of customer satisfaction research.

Figure 2 What should we do to increase customer satisfaction

2.3 Cause and Effect Matrix

The Cause and Effect Matrix as shown in Figure 3 is a tool which is used to prioritize potential causes identified using a Cause and Effect Diagram or a CTQ Tree.
CTQs are listed along the top of the matrix, and then potential causes are listed vertically along the left
side of the matrix. The CTQs are then ranked in terms of importance. The relationship between causes
and effects (CTQs) are ranked and an overall score is calculated for the causes. The causes with the
highest overall score should be addressed first in improvement efforts, because they will have the
largest impact on the Critical-to-Quality Characteristics.

Figure 3 The Cause and Effect Matrix (Omitted)

Part 2