Because of the rapid growth of the service sector, an effective and systematic methodology for quality analysis and improvement is increasingly important. An internet protocol television (IPTV) service provides various contents on demand via television and set-top box with internet line. Its global market size is rapidly growing, but there is a lack of systematic analysis about IPTV service quality. The purpose of this paper is to develop an IPTV service quality model and identify key features and their relationships. The quality function deployment (QFD) method is applied in two phases. The results of QFD application are analyzed and key features and their relationships are identified. Moreover, examples of applying the analysis to improve IPTV service quality are developed for IPTV service providers. As the analysis provided is general and applicable to other services, this paper provides insights into improving service quality, not only for ITPV service providers, but also for service providers in many kinds of industries.Significance: Since IPTV service does not have a long history, there is a lack of systematic analysis about IPTV service quality. This paper develops an IPTV service quality model and indentifies key features and their relationships. The path model and the chain effect analysis would help an IPTV service provider to better understand the mechanism of service quality formation, and then ultimately to enhance the service quality level. The model and insights from this research are applicable to other internet-based telecommunication services.

This paper develops an IPTV service quality model which consists of three layers of features, namely, QoE, QoS and NP. The key features and their relationships are identified via two-phase quality function deployment. The issues on the improvement of the IPTV service quality are also presented.

Quality function deployment (QFD) provides a specific approach for ensuring quality throughout each stage of the product development. Since the focus of QFD is placed on the early stage of product development, the uncertainty in the input information of QFD is inevitable. If the uncertainty is neglected, the QFD analysis results can be misleading. This paper proposes an extended version of the QFD methodology, called Robust QFD, which is capable of considering the uncertainty of the input information and the resulting variability of the output. The proposed framework aims to model, analyze, and dampen the effects of the uncertainty and variability in a systematic manner. The proposed framework is demonstrated through a case study on the ADSL‐based high‐speed Internet service. Copyright © 2007 John Wiley & Sons, Ltd.

An extended QFD planning model is presented for selecting design requirements (DRs) that consider longitudinal effect. In the proposed model, the longitudinal effect is incorporated by introducing a time dimension into the existing house of quality structure. As a consequence of explicitly considering the longitudinal effect, the proposed model yields not only an optimal set of DRs but also the timing of their selection. The proposed model is demonstrated through a case study for improving customer loyalty in the high-speed internet service.

The project objectives, called critical-to-quality (CTQs) in six sigma, should be defined to faithfully reflect the customer requirements. The identification of such a set of CTQs, which is currently done using brainstorming in practice, is a challenging task. Notwithstanding the rapid growth of the six sigma literature, development of a systematic procedure for identifying CTQs has scarcely been addressed. This paper proposes a systematic method for generating CTQ candidates based on the given voice of the customer in the DFSS/C (Design for Six Sigma / Commercial) context. By providing a step-by-step procedure, the proposed method ensures that all the important CTQ candidates are identified and subjective judgments are minimally required. Hence, the shortcomings associated with the existing practice based on brainstorming can be effectively overcome. The unique characteristics of the proposed method are also demonstrated via a case study.

The interior design of passenger cars has been emphasized as an important factor determining their competitiveness in the market. The quality of an interior design can be effectively improved by using information of customer needs and impressions. The present study is intended to develop hierarchies of customer needs and impressions for auto interiors and identify their relative weight in a systematic manner. Three models of different vehicle types (compact, full-size, and recreational vehicle) were selected and corresponding 350 car reviews were collected at 38 internet sites. Then, from the collected reviews, about 2000 customer statements related with needs and impressions were drawn. Then, by interpreting the statements, customer needs and impressions were identified. Next, the needs were grouped by affinity diagram method, resulting in a hierarchy which consists of five categories (aesthetic design, material, functionality, finish, and comfort). In parallel, the impressions were summarized by interior part. Lastly, customer needs and impressions that were addressed by customers with relatively high frequencies were presented.