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Dr Genichi Taguchi is a Japanese engineer and quality consultant who has promoted the use of statistical design of experiments for improving process/product quality at minimal costs. Taguchi has developed a practical and strategic approach for designing quality into products and processes at the product planning, design and development stages, which is often referred to as off‐line quality control. Although many companies in Europe and the USA have used the Taguchi approach to statistical design of experiments with success, very few applications of this method are realised in countries such as the Czech Republic. This paper reports the applications of experimental design advocated by Taguchi in two manufacturing companies in the Czech Republic. The results of the study are stimulating and will lead to wider applications of this methodology for tackling process and quality‐related problems in the Czech Republican industries in the near future.

Efficient techniques of information collection and analysis are essential to all quality and productivity improvement studies. Most established concepts of quality control are passive in nature, intended more for the maintenance of the status quo than for purposeful changes. Statistical experiment design methodologies constitute an active approach which can provide the kind of understanding of process and product characteristics that is needed for managing changes during design and manufacture. Systematic planning of data collection and analysis by these methodologies is a prerequisite for the attainment of higher productivity, as it enables the investigator to identify and evaluate important variables quickly, replacing the conventional single‐variable procedures by a far more efficient approach. The major features and potential applications of experiment design are outlined in a non‐technical language for the appreciation of managers.

This paper discusses the optimization of the process parameters for the hybrid‐layered manufacturing (HLM) process during its weld layer deposition with subsequent surface machining in attaining the desired accuracy and contour profile of the deposited weld layer thickness.

The HLM process integrates the synergic metal inert gas (MIG) – metal active gas (MAG) welding process for depositing the metal layer of a desired slice thickness and perform the computer numerical control (CNC) machining process on the deposited layer to enhance both the surface quality and dimensional accuracy of the deposited layer. For the HLM process the weld bead geometry plays a vital role in determination of the layer thickness, surface quality, build time, heat input into the deposited layer and the hardness attained by the prototype. A feasible weld bead width and heights are to be formulated for the exterior contour weld path deposition and for the interior weld cladding. Thus, Taguchi methodology was employed with minimum number of trails as compared with classical statistical experiments. This study systematically reveals the complex cause‐effect relationships between design parameters and performance.

Statistical design of experiments using orthogonal arrays and signal‐to‐noise (S/N) ratios are performed to constitute the core of the robust design procedure. Experimental confirmations of the performance characteristic using the derived optimal levels of process parameters are provided to confirm the effectiveness of this approach.

The welding parameters such as current, voltage, arc length, wire feed rates, wire stick‐out distance, shielding gas, filler wire diameter, weld speed, etc. will influence on the deposited weld bead geometry. Further investigations are to be carried out during adaptive layer deposition on the induced thermal stresses and its influence on the hardness of the deposited weld layer.

This paper describes a low cost direct rapid tooling process, HLM. This unique methodology would reduce the cost and time to make molds and dies that are used in batch production.

The Taguchi method (Tm) is a powerful problem solving technique for improving process performance, yield and productivity. It reduces scrap rates, rework costs and manufacturing costs due to excessive variability in processes. However, its application by industrial engineers in the UK is limited, in part due to the inadequate statistical education of engineers. This paper presents a simple experiment which can be used in the classroom to teach engineers the basics of the technique and illustrates simple analytical and graphical tools which promote rapid understanding of the results of the experiment.

Experimental design (ED) is a powerful technique which involves the process of planning and designing an experiment so that appropriate data can be collected and then analysed by statistical methods, resulting in objective and valid conclusions. It is an alternative to the traditional inefficient and unreliable one‐factor‐at‐a‐time approach to experimentation, where an experimenter generally varies one factor or process parameter at a time keeping all other factors at a constant level. This paper presents a step‐by‐step approach to the optimisation of a production process (of retaining a metal ring in a plastic body by a hot forming method) through the utilisation of Taguchi methods of experimental design. The experiment enabled the behaviour of the system to be understood by the engineering team in a short period of time and resulted in significantly improved performance (with the opportunity to design further experiments for possible greater improvements).

Adaptive conjoint analysis (ACA) is a market research methodology for measuring utility in business-to-business and customer studies. Based on partial profiles, ACA tailors an experiment’s design to each respondent depending on their previously stated preferences, ordered in a self-assessment questionnaire. The purpose of this paper is to describe advantages and disadvantages of using a partial-profile randomised experiment, the usual system, and to propose a new design strategy for arranging profiles in blocks that improve its performance.

The authors propose a comparison between their design with the commonly used designs, as random designs and the so-called “mirror image”, in their resolution capacity for the estimations of main factors and two-factor interactions with the lowest number of profiles.

Comparing the proposed design over the other two designs highlights certain aspects. The proposed design guarantees more estimation for each experiment than the others and allows the researcher to tailor the design to his or her goals. The authors’ procedure will help researchers to determine an experiment’s resolution capacity before carrying it out, as well as to estimate main factors and two-factor interactions alike.

The authors propose a new design strategy for arranging the profiles in blocks for improving the performance of ACA. This proposal is based on the use of a full-profile approach in which profiles are arranged in two-level factorial designs in blocks of two, and the levels of each factor are codified vectorially.

The effective implementation of the six sigma strategy within UK manufacturing industries, in particular SMEs, can be considered to be poor. SMEs cite high costs and complexity of implementation as being the major limiting factors as to its widespread use. This paper aims to describe the application of six sigma in an SME and to show how the company applied a cost‐effective six sigma methodology to eradicate a critical to quality (CTQ) issue. The paper seeks to conclude by developing a strategic framework for the widespread use of six sigma in SMEs.

This paper applies the six sigma strategy in an SME in order to eradicate a major CTQ issue. It identifies the approach employed, the tools and techniques used and shows the savings that were made through the structured application of the DMAIC procedure, which is at the heart of the six sigma approach.

Through the correct application of experimental design approaches, this paper identifies the optimum parameter settings that enabled the company to eradicate the CTQ issue and achieve significant improvements in quality and cost from a modest financial outlay.

The design and implementation of an SME‐specific six sigma strategy and its application to a real engineering problem will enable companies to apply the techniques and to attain improvements in terms of cost and quality.

The application of the six sigma strategy and the resulting conclusions as to its effectiveness for industry are the real value of this paper. This paper will be valuable for quality professionals, design engineers and manufacturing specialists in a wide range of industries.

Dr Taguchi is a Japanese engineer and an international quality consultant who has made breakthrough improvements in product and process quality through the use of statistical design of experiments (SDOE). The Taguchi method became popular in the West in the 1980s as a means to design robust products and processes. Although many companies and industries have used the method with success, the real benefits of the approach were not realised and fully understood in many cases. This lack of success could be attributed to a number of factors, but mainly because the experiments were treated in isolation and not integrated into a continuous improvement strategy. This paper briefly presents the results of the application of the Taguchi methodology in the UK industry. The paper also illustrates the application of the Taguchi method for optimising the production process of retaining a metal ring in a plastic body in a braking system.

To highlight the application and to compare the effectiveness of the Taguchi and Shainin experimental design processes as applied to aerospace structural components.

This paper applies both the Taguchi and Shainin experimental design techniques to optimizing the design of honeycomb composite joints. The techniques are fully applied, the results analysed and their user friendliness is assessed.

This paper identifies an optimum parameter setting for composite joints gained from applying these experimental design techniques. Significant improvements in joint strength are achieved through identifying a new joint setting.

The adoption of the experimental design techniques outlined in this paper and their application to a real engineering problem will enable a company to apply the techniques and to attain improvements in terms of cost and quality.

The analysis of both the Taguchi and Shainin methodologies and the resulting conclusions as to their effectiveness for industry is the real value of this paper. This paper will be valuable for quality professionals, design engineers and manufacturing specialists in a wide range of industries.

Internet is set to be one of the main channels of distribution in the future and already greatly facilitates product evaluation thanks to the information available on the net. The main advantages of electronic shopping over other channels include the reduced costs of searching for products and for product‐related information. Research has stressed the importance of quality information in web site design. The perceived utility of a web site depends on the perceived utility of its content (i.e. quality of information on product characteristics) and its presentation of that content. This paper compares the ways in which a web site's content and content presentation affect the product choice of two consumer groups from different cultures. The paper aims to discuss these issues.

The authors conduct an exploratory study to determine the key factors which may be used in a later conclusive research. The authors propose a tool based on the statistical design of experiments to determine the number of significant factors used by two market segments (Spanish and US students) when selecting a bottle of wine sold via a web site.

The authors identify key extrinsic factors of consumers' perceived utility when selecting a bottle of wine from a web site and analyse whether cross‐cultural aspects are significant in this choice. The authors assume that web site evaluations made by users from different geographical areas reflect their preferences for more familiar designs.

The sample size does not enable us to determine the significance of certain variables. Moreover, the sample is not fully representative of the overall consumer population, and so inferences cannot be made about all consumers. However, since the study is exploratory with a theoretical content, the results can be considered valid.

Web page designers need to take into account the cultural characteristics of their target market in the presentation and content of their sites.

The internet marketing literature considers cultural differences in web design as a tool to improve user confidence and attitude. However, few studies have examined the effects of the cultural adaptation of web sites on user evaluations. Here, the authors propose a straightforward procedure for calculating the main effects of web site attributes. Yates' algorithm and the normal probability plot, proposed by Daniel, can be implemented in any spread sheet.