development and application of sqfd model …iaeme.com/masteradmin/uploadfolder/sqfd-model.pdf ·...

31
International Journal of Industrial Engineering Research and Development (IJIERD), ISSN 0976 – 6979(Print), ISSN 0976 – 6987(Online) Volume 2, Issue 1, May - October (2011), © IAEME 15 DEVELOPMENT AND APPLICATION OF SQFD MODEL FOR AN INNOVATIVE EMBEDDED SOFTWARE PRODUCT – A CASE STUDY Dillibabu,R. Department of Industrial Engineering, Anna University, India, Chennai. Telephone No: +914422357680 [email protected] Krishnaiah,K. Department of Industrial Engineering, Anna University, India, Chennai. Telephone No: +914422357673 Baskaran,R. Department of Industrial Engineering, Anna University, India, Chennai. Telephone No: +914422357683 ABSTRACT This paper discusses the development and application of Software Quality Function Deployment (SQFD) Model for a new embedded software product. A detailed Literature study has been carried out on the applications of QFD model for software development. An integrated SQFD model with House of Quality (HOQ), Subsystem/Module Deployment Matrix and Technology Deployment Matrix is developed. The proposed SQFD model has been implemented for developing a new embedded software product. From the HOQ matrix reveals that the ‘image capture button’ and ‘imaging’ has been identified as the most important technical requirement for this product. The “Procedure Recording” Subsystem has been identified as the most critical subsystem that affects the design. The most suitable technology that meets the design is the ‘Prism+, pSOS’. Accordingly, recommendations are made to the company. The study demonstrates that the SQFD technique is suitably applied using SQFD Model in an embedded software product, and it is appropriate for the design and development of new software products. KEYWORDS: Software Quality Function Deployment, House of Quality, Embedded Software, Technology deployment matrix, Subsystem Deployment Matrix and New Product Deployment. 1.0 INTRODUCTION Software quality has traditionally been defined in terms of fitness for use based on Juran’s definition of quality. A software product is deemed fit for use if it performs to some level of International Journal of Industrial Engineering Research and Development (IJIERD), ISSN 0976 – 6979(Print) ISSN 0976 – 6987(Online) Volume 2 Issue 1, May – October (2011), pp. 15-45 © IAEME, http://www.iaeme.com/ijierd.html IJIERD © I A E M E

Upload: hoanghanh

Post on 08-Mar-2018

213 views

Category:

Documents


0 download

TRANSCRIPT

International Journal of Industrial Engineering Research and Development (IJIERD), ISSN 0976 –

6979(Print), ISSN 0976 – 6987(Online) Volume 2, Issue 1, May - October (2011), © IAEME

15

DEVELOPMENT AND APPLICATION OF SQFD MODEL FOR AN

INNOVATIVE EMBEDDED SOFTWARE PRODUCT – A CASE

STUDY

Dillibabu,R.

Department of Industrial Engineering, Anna University, India, Chennai.

Telephone No: +914422357680

[email protected]

Krishnaiah,K.

Department of Industrial Engineering, Anna University, India, Chennai.

Telephone No: +914422357673

Baskaran,R.

Department of Industrial Engineering, Anna University, India, Chennai.

Telephone No: +914422357683

ABSTRACT

This paper discusses the development and application of Software Quality Function Deployment

(SQFD) Model for a new embedded software product. A detailed Literature study has been

carried out on the applications of QFD model for software development. An integrated SQFD

model with House of Quality (HOQ), Subsystem/Module Deployment Matrix and Technology

Deployment Matrix is developed. The proposed SQFD model has been implemented for

developing a new embedded software product. From the HOQ matrix reveals that the ‘image

capture button’ and ‘imaging’ has been identified as the most important technical requirement for

this product. The “Procedure Recording” Subsystem has been identified as the most critical

subsystem that affects the design. The most suitable technology that meets the design is the

‘Prism+, pSOS’. Accordingly, recommendations are made to the company. The study

demonstrates that the SQFD technique is suitably applied using SQFD Model in an embedded

software product, and it is appropriate for the design and development of new software products.

KEYWORDS: Software Quality Function Deployment, House of Quality, Embedded Software,

Technology deployment matrix, Subsystem Deployment Matrix and New Product Deployment.

1.0 INTRODUCTION

Software quality has traditionally been defined in terms of fitness for use based on Juran’s

definition of quality. A software product is deemed fit for use if it performs to some level of

International Journal of Industrial Engineering Research

and Development (IJIERD), ISSN 0976 – 6979(Print)

ISSN 0976 – 6987(Online) Volume 2

Issue 1, May – October (2011), pp. 15-45

© IAEME, http://www.iaeme.com/ijierd.html

IJIERD

© I A E M E

International Journal of Industrial Engineering Research and Development (IJIERD), ISSN 0976 –

6979(Print), ISSN 0976 – 6987(Online) Volume 2, Issue 1, May - October (2011), © IAEME

16

satisfaction, in terms of functionality and continuous operation (William and Raja 1995) and

(Yoji 1997). An important element of software quality is the reduction of management risk. Late

delivery, cost overruns, inadequate product performance, and a short product life are management

risks that must be controlled along with fitness for use to obtain software quality. These

management risks relate to the process of developing software and not the software product itself.

Quality Function Deployment (QFD) is a useful quality analysis and improvement tool with

many advantages. The following are the advantages of QFD

(i) Fewer and earlier design changes

(ii) Reduced Product Development cycle time

(iii) Fewer startup problems

(iv) Easier documentation

(v) Fewer field problems

(vi) Warranty claim reduction

(vii) Development of cross-functional team work

(viii) Improved design reliability

(ix) Customer Satisfaction

QFD is also employed for designing IT-related products (software industry). When using QFD, it

is important to understand the needs of the customers, and then we can design or modify the

product to meet their needs (Ronald 1996). The manufacturing QFD (Taeho and Kim 1998) was

developed in Japan in the mid 60’s by Yoji Akao and Shigreu Mizuno. QFD is a method to

transfer customer needs into product and process requirements. The idea is to develop a product

by focusing the effort and limited resources of a project team on what delivers the best value to

the most important stakeholders. Adaptation of the classic QFD applicable to manufacturing

industries to software products is termed as SQFD.

The unique characteristics of software development necessitate the modification of conventional

QFD for use in deploying software design. The first characteristic is that software development is

not a repetitive production process that must be designed for each product. QFD has been

originally conceived as a way of deploying customer requirements throughout the production

process of a product, from design to manufacturing. Software elements are developed to a set of

design specifications. In QFD this would equate to a part of product deployment.

The second major difference between manufacturing and software development is that the

customer requirements are not directly met by specific technical specifications. Unlike

manufactured goods, software or information systems are typically intended to provide support

infrastructure or to act as an enabling mechanism for an organizational process. In QFD, customer

requirements are translated into technical specifications for a particular product. In the case of

software or information systems development, customer needs are met by providing certain

system functions. These system functions may require the development of one or more software

systems. For example; the customer needing “accurate inventory information” would be require

the construction of inventory tracking software, purchasing and receiving software, and cost

management software. These individual program elements would require finally an integration

structure to meet the stated customer requirements. SQFD model with GQM (Goal Question

Metric) is also studied and is shown in Fig 1.

2.0 LITERATURE

Several Researchers have developed or applied QFD models for engineering/manufacturing

products (Georg et al. 1995; Glenn 1993; Tan, Xie and Chia 1998; Taeho and Kim 1998; Yoji

1997; Yoji and Mazur 2003). SQFD model is based on assessment of impact of technical

attributes on satisfaction of customer requirements (Liu et al. 2006). Software requirements

International Journal of Industrial Engineering Research and Development (IJIERD), ISSN 0976 –

6979(Print), ISSN 0976 – 6987(Online) Volume 2, Issue 1, May - October (2011), © IAEME

17

validation uses SQFD tools (Joao, Pedro and Ana 2005). SQFD is used also to evaluate software

quality (Pedro, Marcos, Jose and Luis 2005). But only a very few researchers have contributed to

Software Quality Function Depolyment (Georg and Schockert 2003; Georg, Schockert and

Werner 1995), (Ohmori 1993), existing SQFD models reveals some of the drawbacks which are

presented in Fig 2. From the literature review it is found that very few researchers have developed

and applied SQFD models to practical cases. Also the existing models have several drawbacks as

listed in Fig 2. In this study it is proposed to develop SQFD model for a new embedded software

product and implement it in a leading software company.

3.0 DEVELOPMENT OF THE PROPOSED SQFD MODEL

Great Success has been derived from the use of SQFD by a number of companies. The previous

models have been implemented either for a new product development or as an intensifier or

enabler of the key process of the customer organization. Most of the existing SQFD models have

the components of competitor and technical analysis and as such these cannot be applied to

embedded products. The previous SQFD model had the weakness of not employing the “house of

quality” form and hence the developers cannot explicitly examine the relationships between

technical requirements or the “hows” listed along the x-axis of the matrix (William and Raja

1995). The effects due to product or process characteristics remain unknown, and therefore

cannot be improved. Therefore, the following three matrices are proposed to be included in the

Proposed SQFD Model.

(i) Software House of Quality (S-HOQ) Matrix

(ii) Subsystem or Module Deployment Matrix

(iii) Technology Deployment Matrix

3.1 Software House of Quality (S-HOQ) Matrix

The utility of QFD is that it requires a company to clearly articulate the means by which it will

achieve customer requirements. It relates customer or market needs to be high-level internal

technical design requirements using a planning matrix called the house of quality. The basic

structure of the house of quality is shown in fig 4. Listed on the left side of the matrix is what the

customer needs or requires. Listed along the top of the matrix are the design attributes or

technical requirements of the product; these are how the product can meet customer requirements

shown in additional sections on the top, right, and bottom sides are correlations among the

requirements, comparisons to competitors, technical assessments, and target values.

The procedure suggested by Ronald (Ronald 1996) and (Yoji 1997) has been followed in

developing the S-HOQ matrix (Fig 6). The details of the S-HOQ matrix are presented below.

(i) Whats and Customer Importance: The voice of the customer or the customer requirements are

gathered through brainstorming (Fig 8, step 1) comprising the representatives of the client

company who produces the product. These requirements are grouped into related categories

using affinity diagram and presented as whats in the S-HOQ (He, Staples, Ross and Court 1996).

Using Analytic Hierarchy Process (Taeho and Kim 1998) and Paired Comparisons, ratings for

the whats are identified in a scale 1 to 10 by brainstorming (Fig 8, step 1). One implies low

importance or priority and 10 imply high importance or priority.

(ii) Hows: The hows (technical requirements) are obtained by conducting a brainstorming.

Although the process is often more technical at this point, the team shall still include

representatives of all functions in the organization. The Hows are recorded in the voice of the

engineer. Hows usually represent the product features, design requirements, product

characteristics, product criteria, substitutes of quality characteristics and technical requirements.

The hows represent the means by which a company responds to the user wants and needs. These

International Journal of Industrial Engineering Research and Development (IJIERD), ISSN 0976 –

6979(Print), ISSN 0976 – 6987(Online) Volume 2, Issue 1, May - October (2011), © IAEME

18

technical requirements are listed along the top of the software House of Quality. Each technical

requirement may affect one or more of the customer voices.

(iii) Target Values: The potential Hows are quantified by fixing target values by conducting

another brainstorming. If any technical requirement is not quantifiable then at least a qualitative

statement to measure that technical requirement has to be given. These target values are recorded

in the voice of the engineer table itself.

(iv) Relationship Matrix and Validation of Relations: The relationship matrix (John 1999; Tan et

al. 1998; Ohmori 1993) is the most important part of the HOQ. As most of the data are collected

through brainstorming, there is a need to validate the important outcomes of the brainstorming

using any quantitative technique. One way is to design a questionnaire and obtain responses from

the developers and validate using statistical testing of hypothesis.

The relationships between customer requirements and technical requirements are established

through brainstorming together with the customer representatives. These relationships are related

between every what and every how. All relationships are categorized as either strong, medium or

weak. Different symbols are used to signify different relationship strengths (circle with dot in the

center signifies a strong relationship, blank circle signifies a medium relationship and triangle

signifies a weak relationship). The allocation and categorization of the relationships are carried

out through careful consideration and double-checked a number of times.

(v) Correlation “Roof” Matrix: This matrix assists the software engineers to specify the various

engineering features that have to be improved collaterally. The roof contains the most critical

information which is used to balance the trade-offs when addressing the customer benefits. These

relations are obtained through brainstorming with the members of the QFD team. Different

symbols are used to indicate the strength of the relationships. The correlations are categorized as

strong positive relationship, positive relationship, negative relationship and strong negative

relationship. A blank cell represents no relationships. The positive symbols show which Hows

support each other and the negative symbols show which Hows are in conflict.

(vi) Organizational Difficulty: The organization difficulties are assessed by conducting a

brainstorming and are represented in a scale of 1 to 10. One imples low difficulty in satisfying the

particular technical requirement and 10 implies high difficulty in satisfying the particular

technical requirement.

(vii) Weightage Factor: The weightage scheme is selected by conducting a brainstorming session.

In this meeting usually only the members (developers) of the QFD team are present. This

selection was based on the gap between the relations categorized as strong, medium and low.

These weightage factors are then recorded in the data template.

(viii) Absolute Importance: A cell (i,J) in the relationship matrix of HOQ represents a strong,

medium or weak relationship between ith customer requirement (CR) and j

th Technical

requirement (TR). The absolute and relative importance of TRs is computed using the Customer

Importance of CRs and the relationship ratings (Taeho and Kim 1998).

For each TR, the absolute importance rating is computed as

m

AIj = ∑ CIi * Rij ……………………(1)

i=1

International Journal of Industrial Engineering Research and Development (IJIERD), ISSN 0976 –

6979(Print), ISSN 0976 – 6987(Online) Volume 2, Issue 1, May - October (2011), © IAEME

19

where

AIj is Absolute Importance of TRj, j = 1,...,n

CIi is Customer Importance i.e., importance rating of CRi,

i = 1,...,m

Rij is Relationship rating representing the strength of the relationship between CRi and

TRj.

(ix) Relative Importance: The absolute importance rating can then be transformed into the

Relative Importance rating, RIj, as

AIj

RIj = ………………………………… (2)

n

∑ AIk

k=1

The larger the RIj, the more important is TRj. Thus, without consideration of any other

constraints such as cost and time, TRs should be incorporated into the product of interest in the

order of their relative importance rating to achieve more customer satisfaction. The qualitative

relationship viz strong, medium and weak are generally assigned a value of 9, 3 and 1

respectively for obtaining the ratings (Ronald 1996) and (Yoji 1997). However these values can

be arrived at by conducting a brainstorming session for specific cases in practice. After

computing the absolute and relative importance of the Technical requirements they are

normalized to a scale of 1 to 10. 1 implies low importance and 10 implies high importance or

priority.

3.2 Subsystem or Module Deployment Matrix

The Subsystem or module deployment matrix is prepared in a manner very similar to the S-HOQ

matrix which is shown in Fig 6 (Mekki and Sherif 1997; Ronald 1996; Yoji 1997). Each critical

subsystem or module requires the incorporation of all the technical requirements into the product

and is designed by conducting brainstorming with the engineers. The technical requirements

defined in the S-HOQ matrix become whats that are listed down on the left side of the subsystem

or module deployment matrix along with priorities (based on the normalization of S-HOQ matrix

relative importance ratings) and target values.

Relationship Matrix: Relationships are established between technical requirements and the critical

subsystem or module. These relationships are then categorized as strong, medium, or weak and

are validated using a questionnaire (brainstorming) and hypothesis testing.

Importance Rating of Subsystem: Importance rating of each subsystem or module are calculated

using equation (1) with slight modification. In Subsystem or Module deployment matrix, a cell (i,

j) in the relationship matrix represent a strong, medium, or weak relationship respectively

between ith Technical requirement (TR) and j

th Subsystem (SS). The importance rating of

Subsystem is computed using the normalized importance of TRs and the relationship ratings

(Taeho and Kim 1998). For each SS, the importance rating is computed as

International Journal of Industrial Engineering Research and Development (IJIERD), ISSN 0976 –

6979(Print), ISSN 0976 – 6987(Online) Volume 2, Issue 1, May - October (2011), © IAEME

20

m

IRj = ∑ NIi * Rij …………………. (3)

I=1

where

IRj is Importance Rating of SSj, j = 1,...,n

NIi is Normalized Importance of TRi, i = 1,...,m

Rij is Relationship rating representing the strength of the relationship between TRi and

SSj

3.3 Technology Deployment Matrix

The technical requirements defined in the S-HOQ Matrix shall become the whats listed on the left

side of the Technology deployment matrix along with priorities and target values. This matrix is

developed similar to that of subsystem/module matrix (Fig 6). The only change here is that the

subsystem/module is replaced by the term technologies is shown in Fig 7.

4.0 PROPOSED SQFD MODEL

The proposed SQFD Model is shown in Fig 8. It is an integrated model of S-HOQ

Subsystem/Module Deployment Matrix and the Technology Deployment Matrix. This model is

validated through a case study.

5.0 IMPLEMENTATION OF THE SQFD MODEL

The proposed model has been implemented in one of the leading software companies in India.

The company is a world leader for medical products and has a large global market share in the

Endoscope tools. The endoscope uses a combination of fiber optics and electronics for

performing its function. All the endoscope used today is reusable and need 8-10 hours of

sterilization and disinfection process before they can be reused.

Some of the functions affecting the performance of the products due to the existing software are

presented below:

(i) Printing

(ii) Motor start and Stop Motion Command

(iii) Jet wash on/off status and flow rate setting

(iv) Joystick of speed command

International Journal of Industrial Engineering Research and Development (IJIERD), ISSN 0976 –

6979(Print), ISSN 0976 – 6987(Online) Volume 2, Issue 1, May - October (2011), © IAEME

21

(v) Brightness and contrast adjustment

(vi) Image capture button and imaging

(vii) Recording of Image frame and camera video functions

(viii) GUI navigation commands and SUD connector functions

(ix) Alert Message and Power supply adjustment

(x) Record Camera video data to the DVD

(xi) Database for patients, physicians and procedures

(xii) Directions for use.

Some of the problems in the present endoscope procedure are listed below:

(i) Reusable scope calls for strict sterilization and disinfection process.

(ii) High capital cost for the probes and the allied peripherals and sterilization

equipment.

(iii) High frictional force felt by the patient, necessitating patients to be sedated,

increasing the complexity of the procedure as well as patient recovery time.

(iv) Less number of cases possible by the physician due to long sterilization and

dis-infection process.

(v) Risk of secondary infection due to improper sterilization.

In-spite of sterilization the risk of secondary infection has been reported. This risk

has resulted in reluctance among the patients to undergo colonoscopy procedures. This status is in

existence for the last 25 years, despite progress in the colonoscopy form a simple bare eye viewed

system to a sophisticated CCD camera based system with digital imaging functions. But the

system of reuse has never changed. The client is capitalizing the opportunity of an infection free

safe procedure as their unique selling proposition of their product. Coppelius Console System is

the base unit to which the single use probe is attached and the endoscopy procedure is carried out.

The case company is going to develop embedded software for the endoscope probe. SQFD model

has employed to overcome the problems stated above and improve customer satisfaction. The

steps in its implementation are listed and discussed below.

5.1 Pre-Planning

Pre-planning includes setting the project goals, determining the time schedule, cost planning and

forming the SQFD team. Apart from these activities, the planning phase of a SQFD

implementation includes defining the project’s content (product definition), identification of the

customer groups and their importance for the development ahead as well as selecting customer

representatives. This phase is called as Pre-Planning and consists of normal meetings and

brainstorming sessions of the persons in charge of the project.

International Journal of Industrial Engineering Research and Development (IJIERD), ISSN 0976 –

6979(Print), ISSN 0976 – 6987(Online) Volume 2, Issue 1, May - October (2011), © IAEME

22

5.2 Building the Software House of Quality (S-HOQ)

The entire SQFD process has been carried out by a QFD team with members from all

departments (development, quality management, marketing, sales, service, etc.), and the client

company representatives. Usually formal market research process is applied using focus groups

and in-depth qualitative interview techniques to assess the customer requirements. For the

embedded software development the end user requirements have been obtained from the client

organization, which in turn got them from the actual user of the hardware equipment in which the

embedded software is an integral part.

(i) Whats and Customer Importance: Customer requirements are structured using affinity and tree

diagrams are shown as whats of the software-HOQ (Fig 7). The Whats are ranked in order of

importance using the Analytic Hierarchy Process (Yoji Akao and Mazur 2003) and pair-wise

comparison (Georg, Schockert and Werner 1995). The priority of customer importance displayed

in the HOQ next to each customer voice has been obtained from the QFD team in a scale of 1 to

10. This gives the customer importance or priority rating for the whats of the software-HOQ. One

implies low importance of priority and ten implies high importance of priority.

(ii) Hows : The technical requirements obtained similar to that of customer requirements are

shown as hows of the Software-HOQ carried out similar to the identification of customer

requirements, using a Voice of the Engineer (Fig 8), and is shown in Fig 9. The difference is that

the members of the QFD team consist of the developers during the brainstorming session.

(iii) Target Values: The target values are obtained by converting technical requirements into

measurable quality elements. For the product in case these have been arrived at during the

internal QFD meeting.

(iv) Relationship Matrix and Validation of Relations: The relationships between customer

requirements and technical requirements have been established through brainstorming involving

the customer representatives also. The allocation and categorization of the relationships are

carried out through careful consideration and are double-checked a number of times.

Referring to Fig 9, there is a strong relationship between the customer requirement ‘store image’

and the technical requirement ‘recording of image frame’. Similarly there exist a medium

relationship between the customer requirement ‘responsive tip control’ and the ‘technical

requirement ‘speed oscillation’, and a weak relationship between customer requirement

‘electronic documentation’ and the technical requirement ‘GUI navigation command’. The

customer importance and organization difficulty ratings were obtained through brainstorming are

validated using a questionnaire and hypothesis testing. A Questionnaire (Fig 12-21) has been

developed in MS Excel and sent through E-mail to get response from the developers.

(v) Correlation “Roof” Matrix: The correlation “roof” matrix has been constructed next. This

matrix assists the software engineers to specify the various engineering features that have to be

improved collaterally. The roof contains the most critical information which is used to balance

the trade-offs when addressing customer benefits. These relationships are obtained through

brainstorming with the members of the QFD team. The correlation matrix is constructed using the

relationship keys such as:

An inclined hash symbol for strong negative correlation, a multiplication symbol for negative

correlation, a blank circle for positive correlation and circle with dot in the center for strong

positive correlation. In Figure 9, blank cell represents no relation and others shown are only

positive correlations.

International Journal of Industrial Engineering Research and Development (IJIERD), ISSN 0976 –

6979(Print), ISSN 0976 – 6987(Online) Volume 2, Issue 1, May - October (2011), © IAEME

23

(vi) Organizational Difficulty: These measures provide the software development organization

with a quantitative assessment of their ability to support embedded software development

processes. Such an analysis provides the development organization with:

• Quantitative indicators of changes in organizational priorities;

• Indicators of the effectiveness of software development processes.

The latter point supports continuous improvement efforts on the part of the organizational

software development function. The organization difficulty is represented on a scale of 1 to 10.

One implies low difficulty in satisfying the particular technical requirement and ten implies high

difficulty in satisfying the particular technical requirement. Referring to Figure 9, the company

has a low difficulty of one in satisfying the technical requirement ‘database for patients and

physicians’ and a high difficulty of six in satisfying the technical requirement ‘general

requirement for standards’.

(vii) Weightage Factor: A weightage factor is also attached to each relationship. The weightage

scheme is selected by conducting a brainstorming with the members of the QFD team which

include the developers. The weightage scheme of 9-3-1 is used (Ronald 1996) and (Yoji 1997).

“9” for a strong relationship, “3” for a medium relationship and “1” for a weak relationship.

(viii) Absolute Importance: The absolute importance AIj for each technical requirement is

calculated using the equation (1). In Fig 9, a sample value for one absolute importance is shown.

In the first column the technical requirement “Printing” has a strong relationship with the

customer requirement ‘printing of images by printer’, weak relationship with ‘must be versatile’

and strong relationship with ‘printing images during and after procedures’.. Thus the column

weight for the first column is computed as (9X9) + (7X1) + (9X9) = 169.

(ix) Relative Importance: The Relative Importance (RIj) for each technical requirement is

calculated using the equation (2). In Fig 5, it is represented graphically as histogram. The

column weights are used to identify the technical requirements for quality improvement.

Normalization of Importance: The relative importances of the technical requirements are

normalized on 1 to 10 scale. One implies low importance and 10 implies high importance. The

normalized rating will be used as the priority ratings in the subsequent phases of Subsystem or

module deployment matrix and Technology deployment matrix. The column weights in the

matrix indicate which technical requirement has to be addressed first to improve quality. Then in

Fig 9, the technical requirement “image capture button & imaging” carrying a highest weightage

of 220 needs to be taken up first.

5.3 Subsystem or Module Deployment Matrix

The technical requirements defined in the Software-HOQ matrix shall become the whats for the

Subsystem or Module deployment matrix (Fig 10). The target values are also same as that of

HOQ matrix. The priority ratings are obtained by normalizing the relative importance ratings of

the HOQ. Some of the technical requirements with low priority ratings are not found in the

Module deployment matrix. The critical Subsystems/Modules (Fig 10) required incorporating all

the technical requirements into the product are obtained through brainstorming. Other aspects of

the matrix viz relationships and their validation, wightages and importance ratings are arrived at

similar to that of HOQ. These matrix priorities the critical subsystems based on relative

importance ratings for quality improvement strategy.

5.4 Technology Deployment Matrix

International Journal of Industrial Engineering Research and Development (IJIERD), ISSN 0976 –

6979(Print), ISSN 0976 – 6987(Online) Volume 2, Issue 1, May - October (2011), © IAEME

24

This matrix is also constructed similar to that of subsystem/module deployment matrix by

replacing the subsystem or module block by the Technology block (Fig 11). This contains

alternative technologies suitable to attain the technical requirements. This matrix facilitates the

selection of the technology based on the absolute/relative importance ratings. From Fig 11 it is

seen that the technology “Prism+, pSOS” is most suitable one for the embedded system software.

5.5 Validation of SQFD Model

A survey has been conducted to assess the impact of SQFD before and after its implementation.

Before implementing SQFD, company has been practicing the traditional quality improvement

practices. A questionnaire (Fig 22) has been designed and sets to developers and quality

professionals in the software companies before and after the implementation of SQFD. The

questionnaire contains a set of question on design goals, success factors (Georg et al. 1998) and

results achieved (http://sern.ucalgary.ca/course/seng/613/F97/grp2/report.htm).

The factors are assigned a five point Likert scale: 1-Results not achieved at all, 2-Results not

achieved slightly, 3-Can’t say, 4-Result achieved slightly and 5-Result achieved very well. The

data from the respondents are analysed and shown in Figure 3. The figures in the table are the

mean values of the responses obtained. From Figure 3 it is seen that the implementation of SQFD

produced better results in three areas. A paired ‘t’ test indicates that the overall impact of

implementation of SQFD is significant.

6.0 FINDINGS AND DISCUSSIONS

The development and implementation of SQFD model for a new embedded system software

product has been demonstrated through a case study. This approach can easily be generalized for

many other software development products. It can be concluded that this method is feasible for

defining, measuring, and improving the quality of software. QFD is a powerful tool in TQM and

has, until recently, only been used in manufacturing and other engineering related industries.

Currently all the quality tools including QFD are being applied to software development

processes also.

The following observations are made from the case study:

(i) From Fig 9, it is found that the most important technical requirement that affects customers’

quality is ‘image capture button & imaging’ and the second most important technical requirement

is ‘recording of image frame’. Sine these two have highest absolute importance rating of 220 and

178 respectively.

(ii) Similarly the most critical subsystem that affects design is ‘Procedure Recording subsystem’

and the second most critical subsystem is ‘User Interface subsystem’ (Fig 10).

(iii) The most suitable technology that affects design is ‘Prism+, pSOS’ and the second most

suitable technology is ‘Code Warrior’ (Fig 11).

(iv) The least important technical requirements are ‘Bolus wash variable on the doctors’ monitors

and the ‘Alarm Tones’ (Fig 9).

(v) The least critical subsystem is the ‘User Help Subsystem’ and the next least critical subsystem

is ‘Graphics subsystem’ (Fig 10).

(vi) The least suitable technology is the ‘SECSIMPro’ and the next least suitable technology is

‘Rational suite’ (Fig 11).

Based on these findings it is recommended that the company should direct its efforts and

resources to improve the quality of performance of the Images Capture button and the Imaging

and Recording of Image Frames.

Care should be taken in developing the ‘Procedure Recording’ and the ‘User Interface’

subsystems, as these are the most critical subsystems and a minor bug or defect may result in a

International Journal of Industrial Engineering Research and Development (IJIERD), ISSN 0976 –

6979(Print), ISSN 0976 – 6987(Online) Volume 2, Issue 1, May - October (2011), © IAEME

25

major quality loss. It is also clear that the developers can use the technologies such as ‘Prism+,

pSOS’ and ‘Code Warrior’ for developing this particular embedded software product. It is

suggested that the company fan afford to compromise on the technical requirements such as the

‘Bolus wash variable on the doctors’ monitor’ and the ‘Alarm Tones’ which have least

importance.

Further study is required to determine is this progression does indeed support the development of

software to support business processes. Specific issues include;

(i) Refinements to the deployment scheme use for SQFD

(ii) The development of meaningful quantitative measures to evaluate the priority of

requirements

(iii) The development of quantitative measures to support trade-offs between

implementation deployments

(iv) Formal feedback mechanism to evaluate the level of improvement attained in

meeting the support requirements of business processes.

(v) Formal feedback mechanism to evaluate the benefits obtained by the organization

after implementing the proposed SQFD model.

REFERENCES

1. Ammar H.H., Nikzadeh T. and Dugan J.B. (1997), ‘Petrinets: A methodology for risk assessment

of function specification of software systems using colored’, Proceedings fourth international

software metrics, pp. 108-117.

2. Georg Herzwurm, Gabriele Ahlemeier, Sixten Schockert and Werner Mellis (1998), ‘Success

Factors of QFD Projects’, Proceedings of the World Innovation and Strategy Conference, Sydney,

Australia, pp. 27-41.

3. Georg Herzwurm and Sixten Schockert. (2003), ‘The leading edge in QFD for software and

electronic business’, International Journal of Quality and Reliability Management, Vol. 20, No. 1,

pp. 36-55.

4. Georg Herzwurm, Sixten Schockert and M.Werner. 1995. Higher Customer Satisfactin with

Prioritizing and Focused Software Quality Function Deployment. Transaction of the 7th

Symposium on QFD, QFD Institute, Novi, MI.

5. Glenn, H.M. 1983. Quality Function Deployment for a Medical Device. Sixth Annual IEEE

Computer based Medical Systems Symposium.

6. He Z., Staples G., Ross M. and Court I. (1996), ‘Japanese quality tools in software process

improvement’, The TQM Magazine, vol.8, No.4, pp. 40-44.

7. Joao, R., A. Perdro, and R. Ana. 2005. Software Requirements Negotiation using the software

quality function deployment. Springer-Verlag, Vol 3706, pp.308-324.

8. John, M.N.2001. Competitive Manufacturing Management. Tata Mcgraw Hil.

9. John, K. 1999, Using Quality Function Deployment in Software Requirements Specification.

Andersen Consulting and IDI.

10. Liu, F., K.Noguchi, A. Dhugana, and P.Inuganti. 2006. A quantitative approach for setting

technical targets based on Impact Analysis in Software Quality Function Deployment (SQFD),

Software Quaity Journal, Vol 14, No 2, June 2006, pp.113-134 (22).

11. Mekki I. Elboushi and Joseph S. Sherif (1997), ‘Object-Oriented Software design utilizing quality

function deployment’, Journal of Systems Software, Vol.38, pp. 133-143.

12. Ohmori Akira (1993), ‘Software quality deployment approach: framework design, methodology

and example’, Software Quality Journal. No. 3, pp. 209-240.

13. Pai, W.C.(2002). Quality-enhancing software function deployment model. Information Systems

Management, pp.20-4.

14. Pedro, A., R.S.B.Macros, A.P.Jose, C.Luis. (2005). Analyzing Groupware Design by means of

usability results. 9th

International Conference on Computer Supported Cooperative Work in

Design (CSCWD 2005). Coventry, England, IEEE, Computer Society Press, May 2005.

International Journal of Industrial Engineering Research and Development (IJIERD), ISSN 0976 –

6979(Print), ISSN 0976 – 6987(Online) Volume 2, Issue 1, May - October (2011), © IAEME

26

15. Ronald G. Day (1996), ‘Quality Function Deployment: Linking a company with its customers’,

Tata Mcgraw Hill.

16. Tan K.C., Xie M. and Chia E. (1998), ‘Quality function deployment and its use in designing

information technology systems’, International Journal of Quality and Reliability Management,

Vol. 15 No. 6, pp. 634-645.

17. Taeho Park and Kwang-Jac Kim (1998), ‘Determination of an optimal set of design requirements

using house of quality’, Journal of Operations Management, Vol.16, pp. 569-581.

18. William D. Barnett and Raja M.K. (1995), ‘Application of QFD to the software development

process’, International Journal of Quality and Reliability Management, Vol. 12, No. 6, pp. 24-42.

19. Yoji Akao (1997), ‘Quality function deployment: Integrating customer requirement into product

design’, Productivity Press, pp. 329-339.

20. Yoji Akao and Glenn H. Mazur (2003), ‘The leading edge in QFD: Past, Present and Future’,

International Journal of Quality and Reliability Management, Vol. 20 No.

FIG 1: SQFD AND GQM (Pai 2002)

S.No SQFD PROCESS SQFD WITH GQM

1. Customer requirements are solicited and

recorded

Record customer

requirements in report form.

2. Requirements are converted to a measurable

technical specification

Identify goals of the project

for user, developer and

manager perspective

3. Requirements are mapped to product

specifications (with customer feedbacks) to

create a correlation matrix

Ask questions derived from

goals and measure against

requirements reports

4 Requirements are prioritized by customer Modify and reconfirm the

improper requirements, then

complete matrix.

5. Priorities are determined by multiplying

customer priorities with matrix

Priorities are determined by

multiplying customer

priorities with matrix.

International Journal of Industrial Engineering Research and Development (IJIERD), ISSN 0976 –

6979(Print), ISSN 0976 – 6987(Online) Volume 2, Issue 1, May - October (2011), © IAEME

27

FIG 2: Drawbacks about the existing SQFD Models

S.No The Model Drawbacks

1 The Erikkson and McFadden’s

SQFD Model (William and

Raja 1995)

• Does not employ the House of Quality

(HOQ)

• Developers are not able to explicitly examine

the relationships between implementation

deployments or the hows listed along the x-

axis of the matrix

• There is no statement of how the customer

needs will be met

2. Zultner’s SQFD Model

(William and Raja 1995)

• Does not use the conventional HOQ for its

QFD matrices

• Does not draw the connection between

customer segments and the organizational

processes

3. Shindo’s SQFD Model (Georg

and Schokert 2003)

• Decomposes the customer requirements

directly into functions and data and then into

modules. Does not have any formal

mechanism for determining the importance

of the function.

4. Ohmori’s matrix-of-matrices

SQFD Model (Georg and

Schockert 2003)

• A total of 14 matrices are to be implemented

which is very tedious and complex

5. The Herzwurm & Schockert’s

PriFo SQFD Model (Georg

and Schockert 2003)

• Covers only the first phase i.e product

planning in the classic QFD and designing

part is not dealt with.

International Journal of Industrial Engineering Research and Development (IJIERD), ISSN 0976 –

6979(Print), ISSN 0976 – 6987(Online) Volume 2, Issue 1, May - October (2011), © IAEME

28

Fig 3: Impact of Implementation of SQFD

S.

no

Success Factors, Design Goals or Results

Achieved

Before

Implementation

After

Implementation

1. The technical specification appropriate

products

3.85 3.9

2. Development several product

components in parallel

3.625 3.5

3. Reusability to other similar projects 3.825 4.15

4. Systematic structured proceeding 3.5 4.25

5. Constantness up to the delivery into

production

3.6 3.575

6. Objective product decisions 3.475 3.5

7. Comprehensibleness 3.825 4.3

8. Authentication for product decisions 3.3 3.475

9. Adaptability at customer expectation

changes

3.525 3.725

10. Collection of the real customer

requirements

3.8 4.275

11. Prioritization of the customer

requirements

3.3 4.125

12. Adherence to planned development times 3.8 4.3

13. Foresighted acting 3.5 3.625

14. Function to co-operation 3.225 4.125

15. Tuning of the department goals and

decisions

3.55 3.6

16. Communication satisfactory with technical

personnel

3.925 4.125

17. Communication satisfactory with users

3.725 4.325

18. User requirements met 3.675 3.7

19. Communication satisfactory with

management

3.95 3.65

20. Documentation consistent and complete 3.85 3.525

International Journal of Industrial Engineering Research and Development (IJIERD), ISSN 0976 –

6979(Print), ISSN 0976 – 6987(Online) Volume 2, Issue 1, May - October (2011), © IAEME

29

Fig 4: Structure of House of Quality

Fig 5: Proposed Software House of Quality (S-HOQ) Matrix

Correlation Matrix

Cu

sto

me

r

Imp

ort

an

ce

Relationships between

Customer Needs and Design

Attributes

Importance Weighting

Target Values (How Much)

Technical Evaluation

Importance

Customer Needs

(What)

Design or Technical

Attributes (Hows)

Customer

Perceptions

Competitive

Assessment

Correlation Matrix

Cu

sto

me

r

Imp

ort

an

ce

Relationship Matrix

Target Value

Organizational Difficulty

Absolute Importance

Customer

Requirements

(Whats)

Relative Importance

Technical Requirements

(Hows)

International Journal of Industrial Engineering Research and Development (IJIERD), ISSN 0976 –

6979(Print), ISSN 0976 – 6987(Online) Volume 2, Issue 1, May - October (2011), © IAEME

30

FIG 6: Proposed Subsystem or Module Deployment Matrix

FIG 7: Proposed Technology Deployment Matrix

Relationship Matrix

Importance Rating

Technical

Requirements

(Whats)

Subsystems or Modules

Pri

ori

ty R

ati

ng

Ta

rge

t V

alu

es

Relationship Matrix

Importance Rating

Technical

Requirements

(Whats)

Technologies

Pri

ori

ty R

ati

ng

Ta

rge

t V

alu

es

International Journal of Industrial Engineering Research and Development (IJIERD), ISSN 0976 –

6979(Print), ISSN 0976 – 6987(Online) Volume 2, Issue 1, May - October (2011), © IAEME

31

FIG 8: Proposed SQFD Model

Validate

Validate , Weightage

Brainstorming-3

Correlation matrix

Brainstorming -6 Brainstorming -5

Brainstorming -2

Affinity

Diagramming

Brainstorming-1

Voice of Customer

Customer

Requirements

Customer importance

Voice of Engineer

table

Technical

Requirements with

target value and

organizational

difficulty

Relationship matrix

Absolute and

relative importance

calculation

Correlation matrix

Cu

sto

me

r

Imp

ort

an

ce

Relationship Matrix

Target Value

Organizational Difficulty

Absolute Importance

Customer

Requirements

(Whats)

Relative Importance

Technical Requirements

HOUSE OF

QUALITY

MATRIX

Brainstorming-10 Brainstorming-8

Normalization rating

Brainstorming-11 Brainstorming -9

Subsystem or

module table

Relationship matrix

Technical

requirement table

after deleting least

important ones

Technology table

Relationship matrix

TECHNOLOGY DEPLOYMENT

MATRIX

Pri

ori

ty R

ati

ng

Relationship Matrix

Importance Rating

Technical

Requirements

Technologies

Ta

rge

t V

alu

es

SUBSYSTEM OR MODULE

DEPLOYMENT MATRIX

Pri

ori

ty R

ati

ng

Relationship Matrix

Importance Rating

Technical

Requirements

Subsystem or Module

Ta

rge

t V

alu

es

Brainstorming-4

Validate

International Journal of Industrial Engineering Research and Development (IJIERD), ISSN 0976 –

6979(Print), ISSN 0976 – 6987(Online) Volume 2, Issue 1, May - October (2011), © IAEME

32

FIG 9: HOQ for embedded Software

International Journal of Industrial Engineering Research and Development (IJIERD), ISSN 0976 –

6979(Print), ISSN 0976 – 6987(Online) Volume 2, Issue 1, May - October (2011), © IAEME

33

FIG 10: Subsystem or Module Deployment Matrix

International Journal of Industrial Engineering Research and Development (IJIERD), ISSN 0976 –

6979(Print), ISSN 0976 – 6987(Online) Volume 2, Issue 1, May - October (2011), © IAEME

34

FIG 11: Technology Deployment Matrix

International Journal of Industrial Engineering Research and Development (IJIERD), ISSN 0976 –

6979(Print), ISSN 0976 – 6987(Online) Volume 2, Issue 1, May - October (2011), © IAEME

35

A B C D E F G

1

2 General Details

3 Name

4 Designation

5 Years of Experience

6 E-Mail

7

8 Instructions

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

31

32

33

34

35

36

37

38

39

1. The actual outcome of the brainstorming is given in the work sheet "actual relation".

2. Give your response in the worksheet "agreement", whether you are agreeing with the

actual relations

3. Also give your choice of the realtions in the third worksheet "choice"

FIG 12: S-HOQ Questionnaire - General

International Journal of Industrial Engineering Research and Development (IJIERD), ISSN 0976 –

6979(Print), ISSN 0976 – 6987(Online) Volume 2, Issue 1, May - October (2011), © IAEME

36

International Journal of Industrial Engineering Research and Development (IJIERD), ISSN 0976 –

6979(Print), ISSN 0976 – 6987(Online) Volume 2, Issue 1, May - October (2011), © IAEME

37

Figure 13: S-HOQ Questionnaire – Actual Relations

Figure 14: S-HOQ Questionnaire- Agreement

International Journal of Industrial Engineering Research and Development (IJIERD), ISSN 0976 –

6979(Print), ISSN 0976 – 6987(Online) Volume 2, Issue 1, May - October (2011), © IAEME

38

Figure 15 : S-HOQ Questionnaire- Choice

International Journal of Industrial Engineering Research and Development (IJIERD), ISSN 0976 –

6979(Print), ISSN 0976 – 6987(Online) Volume 2, Issue 1, May - October (2011), © IAEME

39

Figure 16 Subsystem or Module Deployment Questionnaire- Actual Relations

International Journal of Industrial Engineering Research and Development (IJIERD), ISSN 0976 –

6979(Print), ISSN 0976 – 6987(Online) Volume 2, Issue 1, May - October (2011), © IAEME

40

Figure 17: Subsystem or Module Deployment Questionnaire- Agreement

International Journal of Industrial Engineering Research and Development (IJIERD), ISSN 0976 –

6979(Print), ISSN 0976 – 6987(Online) Volume 2, Issue 1, May - October (2011), © IAEME

41

Figure 20: Subsystem or Module Deployment Questionnaire - Choice

International Journal of Industrial Engineering Research and Development (IJIERD), ISSN 0976 –

6979(Print), ISSN 0976 – 6987(Online) Volume 2, Issue 1, May - October (2011), © IAEME

42

Figure 19: Technology Deployment Questionnaire- Actual Relations

International Journal of Industrial Engineering Research and Development (IJIERD), ISSN 0976 –

6979(Print), ISSN 0976 – 6987(Online) Volume 2, Issue 1, May - October (2011), © IAEME

43

Figure 20: Technology Deployment Questionnaire- Agreement

International Journal of Industrial Engineering Research and Development (IJIERD), ISSN 0976 –

6979(Print), ISSN 0976 – 6987(Online) Volume 2, Issue 1, May - October (2011), © IAEME

44

Figure 21: Technology Deployment Questionnaire - Choice

International Journal of Industrial Engineering Research and Development (IJIERD), ISSN 0976 –

6979(Print), ISSN 0976 – 6987(Online) Volume 2, Issue 1, May - October (2011), © IAEME

45

Figure 22 : Success Factors Questionnaire