ENGINEERING CHANGE MANAGEMENT IN

PRODUCT DEVELOPMENT: DYNAMIC

MODELING AND APPLICATIONS

ZHAO JIAN BIN

DOCTOR OF PHILOSOPHY

CITY UNIVERSITY OF HONG KONG

JUNE 2008

CITY UNIVERSITY OF HONG KONG

香港城市大学

Engineering Change Management in Product

Development: Dynamic Modeling and Applications

産品開發中的工程變更管理：動態建模及其應用

by

ZHAO, JIANBIN

趙建賓

Submitted to

Department of Manufacturing Engineering and Engineering Management

制造工程及工程管理系

in Partial Fulfillment of the Requirements

for the Degree of Doctor of Philosophy

哲學博士學位

June 2008

二零零八年六月

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Abstract

Engineering Change Management (ECM) is a crucial part of any product development

project. It is a dynamic process of knowledge generation and reuse, for products, projects,

processes and resources in a company's development and business. However in the literature,

the product-oriented change analyses typically omit the time-related dynamic features.

Investigations in industrial practice show that project managers demand a systematic way to

manage changes in a project's life cycle and development processes. This research models

ECM in a dynamic way at two levels. At the project level, a framework is developed to

predict changes and understand change distribution in product development projects. At the

process level, a genetic algorithm and a simulation tool are developed to generate optimal

process plans. This research covers the following:

First, three Research and Development (R&D) companies were investigated to find out the

industrial needs for ECM and to generate a knowledge-base. These companies vary in their

business nature, management style, organizational structure and product type. One company

was selected for further investigations on their product characteristics, project features,

employees' perspectives and historical change databases. Sixteen crucial factors for ECM,

including organizational, strategic, project, market and product categories, were identified and

discussed in detail.

Second, based on the aforementioned factors and historical data, an exploratory framework

for change prediction and distribution in projects was proposed. Detailed procedures were

developed to demonstrate and implement the framework, with examples.

Third, a Genetic Algorithm-based approach for process planning was developed to facilitate

various planning strategies using the an extended Design Structure Matrix (DSM) model. A

chromosome of the Genetic Algorithm (GA) was used to represent the sequence and cluster

information of tasks. Fitness functions were used to describe the planning strategies, including

parallel alignment and phased alignment, to reduce changes and to minimize design effort.

Fourth, a simulation tool was developed to evaluate the plans generated by the GA. A fitness

function formula was chosen, from among twelve options, to generate optimal plans for both

parallel and sequential alignment strategies. The performance of a plan was shown using

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measures including the mean effort, mean durations, efficiency, change loss, communication

loss, review loss, average engineer's workload, etc.

The industrial investigations, model building, applications, algorithm and tool development

contribute to both the research literature and industrial project management. Using the change

prediction and distribution framework, project managers will be able to identify the core

factors affecting ECM and make optimal resource allocations and project scheduling. The

GA-based DSM analysis makes up for the flaws and insufficiencies of the existing

approaches. The simulation has shown that there is a limit of concurrency and phase division,

the number of which is subject to product and project features. This approach will act as the

foundation of a knowledge-driven ECM approach for industries and will also serve as a good

process planning tool for professional solution providers.

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Table of ContentsDeclaration.............................................................................................................................iAcknowledgments................................................................................................................iiAbstract................................................................................................................................iiiTable of Contents..................................................................................................................vList of Figures.......................................................................................................................xList of Tables......................................................................................................................xiiiAbbreviations.....................................................................................................................xiv

Chapter 1Introduction.........................................................................................................1

1.1Background......................................................................................................................11.2Motivation........................................................................................................................2

1.2.1Industrial needs for better ECM................................................................................21.2.2Lack of research on the dynamic features of ECM....................................................41.2.3Insufficient research on process planning ................................................................4

1.3Research Aim and Objectives.........................................................................................51.4Methodology.....................................................................................................................7

1.4.1Overall methodology.................................................................................................71.4.2Review.......................................................................................................................91.4.3External collaboration.............................................................................................111.4.4Model development, application and validation ....................................................12

1.5Thesis Organization......................................................................................................14

Chapter 2Literature Review: Engineering Change Management and Process Planning.............................................................................................................................17

2.1Engineering Change Management...............................................................................182.1.1Definition and nature of engineering change..........................................................182.1.2ECM practice in industries and research literature................................................242.1.3Models for ECM......................................................................................................352.1.4Change propagation................................................................................................382.1.5Change prediction in product development projects...............................................44

2.2Design Structure Matrix and Process Planning..........................................................472.2.1Design Structure Matrix..........................................................................................472.2.2Process Planning.....................................................................................................54

2.3Summary........................................................................................................................62

Chapter 3Investigations in Current Engineering Change Management Practices......65

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3.1Introduction to TTSHK................................................................................................663.2Characterization of TTSHK's Design Context...........................................................69

3.2.1Software nature........................................................................................................693.2.2Customer driven design...........................................................................................703.2.3Change presentation................................................................................................703.2.4Quality assurance....................................................................................................71

3.3ECM Practice.................................................................................................................713.3.1Engineering Change Order.....................................................................................723.3.2Problem and Change Requests................................................................................73

3.4The Survey on Employees' Perspectives.....................................................................763.4.1Questionnaire design...............................................................................................763.4.2Data collection........................................................................................................773.4.3Basic data analysis..................................................................................................783.4.4Survey summary......................................................................................................81

3.5Change and Project Plan..............................................................................................823.5.1Budgeting based on initiated changes.....................................................................823.5.2Plan based on external and internal milestones.....................................................823.5.3Plan with changes...................................................................................................83

3.6Change and Resource....................................................................................................843.6.1Knowledge and concept to engineering changes....................................................843.6.2Attitude to engineering changes..............................................................................853.6.3Perspectives to the crucial factors..........................................................................853.6.4Dedication to ECM..................................................................................................87

3.7Problems in TTSHK's ECM practice..........................................................................873.7.1Changing requirements from customers..................................................................873.7.2Tight schedule..........................................................................................................883.7.3New employee's inattentiveness..............................................................................883.7.4Communication problems........................................................................................883.7.5Differences in employees' understanding................................................................893.7.6Insufficient impact analysis.....................................................................................893.7.7Lack of tools and visualization................................................................................903.7.8Lack of integrated management systems.................................................................91

3.8Investigations in Other Companies..............................................................................913.8.1Company M.............................................................................................................923.8.2Company P..............................................................................................................95

3.9Summary........................................................................................................................97

Chapter 4Foundations for Dynamic Modeling of Engineering Change Management 99

4.1Model Frameworks.......................................................................................................994.1.1Need for modeling.................................................................................................1004.1.2Project level modeling framework.........................................................................1014.1.3Process level modeling framework........................................................................102

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4.2Change Prediction at the Project Level.....................................................................1024.2.1Initiated and emergent changes.............................................................................1024.2.2Predictability of emergent changes.......................................................................105

4.3Design Process Modeling and Optimization.............................................................1094.3.1Process considerations for change........................................................................1104.3.2Extended DSM for process modeling....................................................................1124.3.3Sequential and parallel process plans...................................................................119

4.4Summary......................................................................................................................121

Chapter 5Crucial Factors for Project Level Change Management and Prediction...123

5.1Needs to Elicit the Factors..........................................................................................1235.1.1Methods to organize factors for ECM...................................................................1245.1.2Methods to organize factors for ECP....................................................................125

5.2Crucial Factors for Successful ECM.........................................................................1255.2.1Organizational factors...........................................................................................1255.2.2Strategic factors....................................................................................................1285.2.3Project factors ......................................................................................................1305.2.4Market factors ......................................................................................................1325.2.5Product factors......................................................................................................1345.2.6Strategies to cope with these factors.....................................................................136

5.3Crucial Factors for Change Prediction.....................................................................1395.3.1Factors for change prediction...............................................................................1395.3.2Experience from TTSHK........................................................................................141

5.4Summary......................................................................................................................146

Chapter 6Project Level Change Prediction Frameworks and Applications...............147

6.1Model Basics................................................................................................................1476.1.1Purpose..................................................................................................................1476.1.2Methodology..........................................................................................................1486.1.3Framework............................................................................................................150

6.2Change Prediction for MCS.......................................................................................1516.2.1Changes categorization.........................................................................................1516.2.2Effort prediction for design and change................................................................1526.2.3Change distribution in project...............................................................................159

6.3Model Discussion and Validation...............................................................................1626.3.1Barriers in modeling.............................................................................................1636.3.2Validating change prediction model......................................................................1656.3.3Validating change distribution model...................................................................1666.3.4Possible ways for model improvement..................................................................167

6.4Model Applications......................................................................................................1686.4.1Better understanding the projects.........................................................................168

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6.4.2Identification of problems in projects....................................................................1696.4.3Reducing change risks...........................................................................................1716.4.4Optimal resource allocation..................................................................................1716.4.5Identify further improvement.................................................................................174

6.5Managerial Implications.............................................................................................1746.5.1Change effort prediction........................................................................................1746.5.2Change distribution in project...............................................................................176

6.6Summary......................................................................................................................178

Chapter 7Process Modeling and Optimal Planning Using Genetic Algorithms.........181

7.1Process Modeling using DSM ....................................................................................1837.1.1Purpose..................................................................................................................1837.1.2Problem formulation.............................................................................................1847.1.3Example of process models...................................................................................185

7.2Genetic Algorithms Design.........................................................................................1907.2.1Encoding................................................................................................................1917.2.2Crossover...............................................................................................................1927.2.3Mutation................................................................................................................1937.2.4Overall Mechanisms..............................................................................................193

7.3Process Planning with Strategies...............................................................................1947.3.1Parallel alignment.................................................................................................1947.3.2Parallel alignment with lead and end clusters......................................................1967.3.3Phased alignment..................................................................................................1987.3.4Phased alignment with maximum concurrency.....................................................201

7.4Lesson Learned from GA...........................................................................................2027.4.1Performance of GA................................................................................................2027.4.2Process planning...................................................................................................205

7.5Summary......................................................................................................................207

Chapter 8Process Plan Analysis Using Simulations......................................................209

8.1Developing a tool for simulation................................................................................2108.1.1Project creator.......................................................................................................2108.1.2Process simulator..................................................................................................2118.1.3Execution viewer...................................................................................................212

8.2Simulation for Parallel Design...................................................................................2148.2.1Description of parallel design scenarios..............................................................2148.2.2Simulation algorithms...........................................................................................2158.2.3Simulation results and GA fitness values..............................................................2168.2.4Performance measures for parallel simulation.....................................................2208.2.5Limits to concurrency............................................................................................222

8.3Simulation for Phased Design.....................................................................................225

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8.3.1Description of phased design scenarios................................................................2258.3.2Simulation algorithms...........................................................................................2268.3.3Simulation results and GA fitness values..............................................................2278.3.4Performance measures for sequential simulation.................................................2308.3.5Limits to phase division.........................................................................................231

8.4Lessons Learned from Simulations............................................................................2348.4.1Simulation tools and algorithms...........................................................................2348.4.2Process planning...................................................................................................235

8.5Summary......................................................................................................................238

Chapter 9Conclusions......................................................................................................239

9.1Core Conclusions.........................................................................................................2399.2Contributions...............................................................................................................240

9.2.1Research contributions .........................................................................................2409.2.2Contribution to TTSHK.........................................................................................242

9.3Evaluation against Research Objectives...................................................................2439.4Limitations of This Research......................................................................................2459.5Future Research Directions........................................................................................246

9.5.1Human factors for product development and ECM..............................................2469.5.2Knowledge-based change management and predication......................................2479.5.3Advanced process planning techniques.................................................................248

9.6Summary......................................................................................................................249

References.........................................................................................................251Appendix A: Questionnaire on ECM..............................................................................267Appendix B: Project Evaluation Form ..........................................................................269

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List of Figures

Figure 1.1 The Design Methodology Spiral (from Eckert, Stacey and Clarkson , 2004)...........8

Figure 1.2 Overall research methodology and framework..........................................................9

Figure 1.3 Thesis contents and organization.............................................................................16

Figure 2.1 A generic ECM process (from Jarratt 2004)............................................................31

Figure 2.2 Scope of Change Propagation..................................................................................39

Figure 2.3 Dynamic change probability and impact (from Carrascosa et al., 1998)................48

Figure 2.4 Scope of process planning for PD project...............................................................55

Figure 2.5 Relationship between EC rate and confidence........................................................61

Figure 2.6 Typical confidence profiles (from Flanagan, 2006).................................................62

Figure 3.1 Research activities in TTSHK.................................................................................66

Figure 3.2 MCS for Metro-transportation systems...................................................................67

Figure 3.3 MCS architecture.....................................................................................................69

Figure 3.4 Requirement change workflow................................................................................72

Figure 3.5 System design change workflow.............................................................................72

Figure 3.6 System and subsystem PCR process workflow (Simplified)..................................74

Figure 3.7 Employee's perspectives on engineering change management...............................86

Figure 3.8 Change management workflow in Company M......................................................93

Figure 3.9 Engineering change order flow involving customers..............................................96

Figure 3.10 Engineering change order flow without customers...............................................97

Figure 4.1 Model framework for project level change prediction..........................................101

Figure 4.2 Model framework for optimal process planning...................................................102

Figure 4.3 Priorities of criteria for change classification........................................................105

Figure 4.4 Characteristics of task groups................................................................................107

Figure 4.5 Change numbers of three telecommunications device development projects......108

Figure 4.6 Two kinds of precedence relationship....................................................................114

Figure 4.7 Common precedence and dependence alignment.................................................115

Figure 4.8 DSM of MCS design process (a part)....................................................................116

Figure 4.9 DSM of Turbine Cooling System design process..................................................116

Figure 4.10 Likelihoods and impacts of precedences and dependences.................................117

Figure 4.11 Extended DSM with durations and sensitivities..................................................118

Figure 4.12 Extended graphic DSM presentation ..................................................................118

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Figure 4.13 Sequential and parallel processes........................................................................119

Figure 4.14 Task-based DSM clustering and team collaboration...........................................120

Figure 4.15 Two-process sequencing and team collaboration................................................121

Figure 5.1 The relationship between change numbers and project sizes................................143

Figure 6.1Framework for change prediction and distribution in projects...............................150

Figure 6.2 Change cost and interchangeability (from column item to row item)...................151

Figure 6.3 DSM for MCS........................................................................................................154

Figure 6.4 Combined risk of change propagation...................................................................155

Figure 6.5 Final initiated change estimation...........................................................................156

Figure 6.6 Milestones in project B (Simplified).....................................................................160

Figure 6.7 Task groups distribution in project life cycle.........................................................160

Figure 6.8 Change numbers and trend in project B................................................................161

Figure 6.9 Change impacts and trend Project B......................................................................162

Figure 6.10 Change number and impact distribution in Project B.........................................167

Figure 6.11 Change number and impact distribution in project G..........................................169

Figure 6.12 Number of opened and closed changes of Project G...........................................170

Figure 7.1 DSM of MCS detailed design................................................................................188

Figure 7.2 DSM representation of the MCS detailed design..................................................189

Figure 7.3 DSM representation of Brake-System design........................................................190

Figure 7.4 Mechanism of SGA...............................................................................................191

Figure 7.5 Integer chromosome encoding of DSM with clusters...........................................192

Figure 7.6 Position based crossover illustration.....................................................................192

Figure 7.7 2ORS mutation illustration....................................................................................193

Figure 7.8 Shift mutation illustration......................................................................................193

Figure 7.9 Parallel alignment of tasks to developers..............................................................194

Figure 7.10 Fore cluster parallel alignment of MSC detailed design.....................................195

Figure 7.11 Two cluster parallel alignment of Brake-System design.....................................196

Figure 7.12 Parallel alignment of tasks with lead and end clusters........................................197

Figure 7.13 Parallel alignment of MCS detailed design with lead and end............................198

Figure 7.14 Multi-phase alignment of tasks............................................................................199

Figure 7.15 Sequential alignment of MCS detailed design in 6 clusters................................200

Figure 7.16 Sequential alignment of Brake-System design in 3 clusters................................200

Figure 7.17 Sequential alignment of MCS detailed design with maximal concurrency.........202

Figure 7.18 Comparison of the performance of mutation operators ......................................203

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Figure 7.19 Impact of DSM density on GA performance.......................................................205

Figure 8.1 Framework of the simulation tool..........................................................................210

Figure 8.2 Spreadsheet as project creator................................................................................211

Figure 8.3 Project simulator....................................................................................................212

Figure 8.4 Probability distribution of project durations.........................................................213

Figure 8.5 Gantt chart of a single run for parallel plan...........................................................214

Figure 8.6 Fitness values and simulation efforts for MCS parallel design.............................219

Figure 8.7 Fitness values and simulation results for BrakeSys parallel design......................219

Figure 8.8 Probability distribution of simulation results for MCS parallel design.................220

Figure 8.9 Performance measures and number of parallel processes for MCS design...........223

Figure 8.10 Performance measures and number of parallel processes for BrakeSys design. .224

Figure 8.11 Fitness values and simulations efforts for MCS sequential design......................229

Figure 8.12 Fitness values and simulation efforts for BrakeSys sequential design................230

Figure 8.13 Probability distribution of simulation results for BrakeSys sequential design....230

Figure 8.14 Performance measures and number of phases of MCS sequential design...........232

Figure 8.15 Performance measures and number of phases of BrakeSys sequential design....233

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List of TablesTable 2.1 An overview of sequencing and partitioning objective functions (from Meier et al.,

2007).........................................................................................................................................51

Table 3.1 Developer's job duties in TTSHK.............................................................................68

Table 3.2 Three types of changes in TTSHK............................................................................75

Table 3.3 Survey data summary................................................................................................77

Table 3.4 Mean and variance of survey result grouped by position..........................................79

Table 3.5 Mean and variance of survey result grouped by project...........................................81

Table 3.6 Number of changes grouped by change source.........................................................93

Table 4.1 Priority of criteria to classify changes.....................................................................104

Table 5.1 Comparison of TTSHK, Company M and Company P...........................................137

Table 5.2 Crucial factors affecting ECM................................................................................138

Table 5.3 Evaluation of the ECP factors in TTSHK's projects...............................................142

Table 5.4 Management coefficient to predict change number................................................143

Table 5.5 Correlation analysis of the affecting factors............................................................144

Table 6.1 Design reuse of Project B from Project G...............................................................153

Table 6.2 Design reuse of project B from project G...............................................................157

Table 6.3 Fine-tune results with affecting factors...................................................................158

Table 6.4 Change rate recording form (single value example)...............................................161

Table 6.5 Current change numbers in task groups..................................................................166

Table 6.6 Critical task groups and their sensitivities...............................................................172

Table 7.1 Developers proficiencies on the tasks.....................................................................187

Table 8.1 Description and formulation of six fitness functions for parallel planning.............217

Table 8.2 Evaluating fitness values against simulation results for MCS parallel design........218

Table 8.3 Evaluating fitness values against simulation result for BrakeSys parallel design. .219

Table 8.4 Simulation results for MCS parallel design with processes variation.....................222

Table 8.5 Simulation results for BrakeSys parallel design with process number variation....224

Table 8.6 Description and formulation of 6 fitness functions for sequential planning...........228

Table 8.7 Evaluating fitness values against simulation results for MCS sequential design....229

Table 8.8 Evaluating fitness value against simulation result for BrakeSys sequential design229

Table 8.9 Simulation results for MCS design with different number of phases.....................232

Table 8.10 Simulation results for BrakeSys design with different number of phases............233

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AbbreviationsCCB Change Control BoardCPM Change Propagation Method (or Model)CR Change RequestCS Change Solution or Change CaseDSM Design Structure MatrixEC Engineering ChangeECC Engineering Change ControlECM Engineering Change ManagementECO Engineering Change OrderECP Engineering Change PredictionGA Genetic AlgorithmPCR Problem and Change RequestPD Product DevelopmentPDM Product Data ManagementPLM Product Life cycle ManagementQA Quality AssuranceSME Small and Medium-sized EnterpriseTTSHK Thales Transportation System (Hong Kong)