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The purpose of this paper is to present and analyze the current literature related to developing and improving the Mahalanobis-Taguchi system (MTS) and to present the shortcomings related to this method for future research.

In this paper, articles in the literature are classified to give an overview on the MT strategy. For this purpose, 46 articles are considered for classification from 2000 to 2013 on the basis of: MTS contribution area, description of the issue, and results.

In this paper a review on the concepts and operations of the MTS was provided as a new method in the field of pattern recognition, multivariable diagnosis, and forecasting. A large number of studies were performed in recent years consisting of developing MTS and MTS case studies. The analysis of the articles showed the fields of MTS which had more potential for future studies and developing. The comparison of the MTS to other methods and the selection of the normal group for constructing the Mahalanobis space have received the most attention by researchers. In addition, several studies concentrated on the use of other methods instead of design of experiments, finding applications for multiclass MTS and finding an alternative for the SN ratio.

This paper contains the publications in the field of MTS chronologically and shows different areas for developing and case studies. It will be useful to researchers and professionals who are interested in pattern recognition, multivariate analysis, and forecasting.

This paper aims to depict the erosion performance of two HVOF-coated micron layers (Colmonoy-88 and Stellite-6) on pump impeller steel (SS-410) by using Taguchi's method. Taguchi's array (L16) was used to optimize the erosion wear (in terms of weight loss) by using four influencing parameters such as rotational speed, solid concentration, average particle size and time which were varied at four different levels.

The experiments were carried out by using a Ducom slurry tester with rotational speed in the range of 750-1,500 rpm, solid concentration of 35-65 per cent by weight, time period of 75-210 min and average particle sizes in the range of < 53 to 250 µm. Bottom Ash with a nominal size range of < 53 to 250 µm was used as erodent. The process parameters were optimized by using Taguchi's method. The ANOVA method was used to validate the results given by Taguchi's method.

The results revealed that the presence of both carbides and borides and the additional presence of Cr in Colmonoy-88 coating enhancing the slurry erosion resistance of Colmonoy-88 coating. Moreover, the chromium and tungsten carbide particles help in increasing the bond strength between the coating and the substrate material. Further, it was also found that the time was the most dominant factor as compared to other factors.

The very less work has been reported on optimization of erosion wear response of Colmonoy-88 and Stellite-6 coatings by using different design of experiment techniques. Further, the erosion wear mechanism of both coatings has been studied by using image j analysis software.

Cost estimation based on expert's judgment is not an ideal approach, since human decisions are usually determined according to general attributes of limited and unstructured experience. The purpose of this paper is to develop a generic model of intelligence and cognitive science‐based method that can play an active role in process cost prediction within the shortest possible time.

In this paper, an intelligent system was conceived for prediction of total process cost of the product. The system is based on the concept of case‐based reasoning. It is a method for solving problems by making use of previous (source cases), similar situations and reusing information and knowledge about such situations. The source case data are generated by Taguchi technique and the cost function calculates the corresponding cost of each experiment in the economic time scale. The target case consists of the process variables whose cost needs to be determined. The cost for the source cases, consisting of the process variables of the already manufactured products are known in priori. The system calculates the similarities between the source cases and target cases and calculates the optimum cost. The fuzzy‐C‐means clustering method provides the model connecting the process parameters with total costs searched for.

The results show that the quality of predictions made by the intelligent system is comparable to the quality assured by the experienced expert. The proposed expert system is superior to traditional cost accounting system and assists inexperienced users in predicting the optimum process cost within the shortest possible time.

The research was limited to the traditional machining process.

The paper can be applied to any process industry and will have immense practical value.

This is the first time an expert system has been developed for the process industry that can calculate the process cost within a few days or a few hours before making an offer to a buyer.

The purpose of this paper is to demonstrate application of the Taguchi method to determine the optimum level of three important parameters (factors) related to the use of a mobile phone for the text message entering task, namely illumination level, noise level and mobile angle that maximizes the performance of mobile phone users.

Three levels of each parameter as available in the literature, except for the mobile angle, were considered. The design of the experiment, as proposed by Genichi Taguchi, was used to conduct nine experiments. A total of 30 male subjects participated in the experimental study. The text message entry task, in the form of Arabic text, was presented to the participating subjects and their performance, measured in terms of mean number of characters entered per minute, was recorded. The signal‐to‐noise (S/N) ratio and the analysis of variance (ANOVA) were employed to investigate the users' performance. Finally, a confirmation test was conducted to verify the validity of the results.

Results showed that, at the illumination level of 475 lux, noise level of 45 dB(A), and mobile angle of 70 degrees, the subjects were quite comfortable, efficient and entered the maximum number of characters in the mobile phone per minute. The noise was found to be the dominant parameter with a contribution of 95.53 percent towards the laid down objective followed by mobile angle, 3.25 percent and illumination level, 0.66 percent.

To the best of the authors' knowledge no study has been conducted in the past to investigate the effect of these parameters on the performance of the mobile phone users. In addition, no attempt has yet been made to find the optimal level of these parameters from a text‐entering viewpoint. The paper represents original research and in the authors' opinion carries significantly important values as it provides new information for those involved in the design of the mobile phone environment.

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.

In the Taguchi’s experimentations, orthogonal arrays, interaction tables, and linear graphs are provided for planning experiments, but they become quite unwieldy when the number of runs is large. The purpose of this article is to propose a quick and easy method for obtaining two‐factor interaction columns in two‐level orthogonal arrays. Geometrical designs proposed by Plackett and Burman are two‐level orthogonal arrays and can be obtained very easily by a successive doubling method. Based on the property of doubling, a NR method using a number representation system whose base is a power of 2 is derived in this article for obtaining two‐factor interaction columns in geometrical designs. Furthermore, since Taguchi’s two‐level orthogonal arrays are obtainable by successive doubling with some column permutations, it is shown that their two‐factor interaction columns can be obtained directly by using the NR method without looking up tables.

This paper seeks to provide a tool for decision makers to make more informed decisions regarding their outsourcing decisions and selection of the appropriate supplier.

The method uses the Taguchi loss function for the inclusion of intangibles in the evaluation and selection of suppliers. Intangibles are defined as factors that have an impact on the selection of an appropriate supplier but are not easily quantified to be included in the financial evaluation. These intangibles are classified as the benefits and risks of using a supplier to perform the outsourcing function. A decision maker has certain expectations regarding these intangibles and a loss occurs when a supplier's performance does not meet the decision maker's expectations. The Taguchi loss function has been selected as a means of measuring the loss. The decision maker defines the target value and the specification limits for each benefit and risk category. The weighted loss scores are calculated where the weights are the importance ratings assigned to benefit/risk categories by the decision maker. Based on this analysis each supplier will receive a weighted loss score for all the pertinent benefit categories and one weighted loss score for all the risk categories. To achieve a single measure, the aforementioned weighted loss scores are combined to determine a single aggregate loss score for each supplier, which is then used to rank them. The supplier who receives the highest ranking (minimum loss score) will be selected to perform the outsourcing function.

The procedure proposed here can help companies to identify the best supplier to perform an outsourcing function.

The paper presents a phased decision model that begins with economic evaluation and then uses Taguchi functions to measure the impact of intangibles.

The purpose of this paper is to study the optimal conditions of the mixed convection in a ventilated square cavity filled with Cu-water nanofluid using the Taguchi method. The paper aims to discuss diverse issues affecting the said model.

The numerical solutions of nonlinear coupled equations are developed by means of the Taguchi method. The Taguchi method is used as an effective way to optimize the design process engineering tests.

The governing equations are discretized using a finite volume method and solved with semi-implicit method for pressure linked equations (SIMPLE) algorithm. The effect of Richardson number (0.01-10), the volume fraction of nanofluid (0-5 per cent), distance of inlet port position from bottom wall of the cavity (0-0.9 H) and distance of outlet port position from top wall of the cavity (0-0.9 H) as effective parameters are analyzed across four levels. This analysis is done for fixed Grashof number 10⁴. The results show that the mean Nusselt number almost decreases by an increase in the Richardson number, volume fraction of nanofluid, position of the inlet port and position of the outlet port. It is found that the cavity with distance of inlet port position from bottom wall of the cavity 0 and distance of outlet port position from upper wall of the cavity 0.9 H at the Richardson number 0.01 and the volume fraction 3 per cent is the optimal design for heat transfer.

As far as the authors know, this model has been investigated for the first time.

The purpose of this paper is to develop a method to evaluate the quality of service delivery process designs, based on how closely they meet process requirements of key stakeholders while taking variability into account.

A Monte Carlo computer simulation of the flowchart of the service delivery process is used to capture the effects of multiple types of variabilities and parametric uncertainties on process variables of interest, and the Taguchi quality loss framework is applied to estimate overall process quality. As an example, a proposed modification to a patient‐treatment process in a hospital emergency department is evaluated.

This paper demonstrated a method that service managers can use to evaluate the quality of service delivery process designs.

This method can evaluate modifications to various aspects of a service delivery process, and can assist managers to fail‐safe the entire process. Furthermore, it characterises process quality using a range of probable values instead of a single value, such as the process mean, and thus provides a more realistic representation of quality.

This paper contributes to service engineering in two ways: by adapting the Taguchi quality loss approach, commonly used to assess manufacturing process quality, to a service delivery process; and by incorporating uncertainty, due to imprecise knowledge of process parameters, into the quality assessment.

The advancement in modern manufacturing technology generated the need to develop new materials for better wear resistance. The purpose of this paper is to use the Taguchi optimization approach to examine which wear parameter significantly affects weight loss and coefficient of friction for RZ5-TiC composite. It is a simple and efficient method to find performance of wear parameter using minimum experimental runs.

RZ5-TiC composites were prepared using RZ5 as matrix, reinforced with TiC through self-propagating high-temperature synthesis technique. In the present work, an attempt has been made to study the influence of wear parameters like applied load (AL), sliding distance (SD) and Wt.% of TiC (WTC) on responses like weight loss and coefficient of friction of RZ5/TiCp composites. The pin-on-disc apparatus used to conduct abrasive wear test. The wear process parameters are optimized for minimum wear based on L27 Taguchi orthogonal design. The Taguchi technique using design of experiments (DOE) is used to obtain the data. The ANOVA and an orthogonal array are used to examine the influence of wear parameters on responses. The purpose is to examine parametric significances which affect responses.

It observed that wear parameters have the significant influence on responses of RZ5/TiCp composites. The interaction of sliding distance/Wt.% of TiC is observed and found significant influence on both responses. The optimum level of the significant wear parameters is achieved based on the maximum S/N ratio for RZ5/TiCp composites. The optimal interaction for weight loss and coefficient of friction is AL1-SD1-WTC3 and AL3-SD1-WTC3, respectively. Finally, the confirmation test is conducted and the results are obtained within the confidence interval.

The current manuscript provides an optimization of wear parameters using Taguchi approach. The extensive experimental data are used for this purpose and effects of wear parameters on responses are analyzed from the presented results. The results obtained are useful in improving the wear resistance of the RZ5-TiC composite.