Application of fuzzy VIKOR for concept selection in an agile environment

Due to the increasing competition, modern manufacturing organisations are adopting agile manufacturing (AM) paradigm. AM enables the speedy production of customised, high-quality products in varying lot sizes. Concept selection in the context of AM is a typical multi-criterion decision making problem as it involves several agility criteria. The case organisation needs to select the best concept among five alternative designs. VIKOR (VlseKriterijumskaOptimizacija I KompromisnoResenje in Serbian, meaning multi-criteria optimization and compromise solution) has been used to select the best concept design. Based on the inputs gathered from decision makers, concept design (A3) has been found the best concept design from the perspective of agility. The result derived from Fuzzy VIKOR has been compared with fuzzy TOPSIS (technique for order preference by similarity to an ideal solution) methodology. The selected concept design has been subjected to implementation in the case organisation.     

Structural Equation Modelling of lean manufacturing practices

The purpose of this research study is to analyse lean manufacturing practices in different industries and to identify the critical factors for its success implementation. Despite the fact that lean manufacturing has been frequently promoted as a means of improving business competitiveness, little empirical evidence exists in the literature validating its positive link with organisational performance. Lean manufacturing practices not only help in reducing the number of defects but also reduces the cost of production. For this purpose, empirical data is collected to measure the lean manufacturing practices prevailing in different industries located in Tamil Nadu, India. A Structural Equation Modelling (SEM) technique is used to build the measurement and structural models. Later, statistical estimates are used to validate the model that has been built. The data analysis helps to determine whether to accept or reject the hypothesis that has been stated based on the structural model. The result shows how lean manufacturing practices are correlated and help in improving the organisational performance among the industries being surveyed.     

Agility index measurement using multi-grade fuzzy approach integrated in a 20 criteria agile model

This paper reports a research carried out to assess the agility level of an organisation using a multi-grade fuzzy approach. Agility refers to the capability of an organisation to respond quickly in accordance with the dynamic demands of the customers. During this research, an agility index measurement model containing 20 criteria incorporated with the multi-grade fuzzy approach was designed. Subsequently, the data gathered from a manufacturing company was substituted in this model and the proposals for enhancing the agility level of this company were derived. The usage of the model contributed in this paper will indicate the actions required to enhance an organisation's agility level. This process will accelerate the absorption of agility characteristics in modern organisations.     

Optimization of friction welding of tube to tube plate using an external tool by hybrid approach

Several developments have been observed in the field of materials processing and welding is a vital metal joining process that has potential industrial applications. Friction welding of tube to tube plate using an external tool (FWTPET) is a relatively newer solid state welding process used for joining tube to tube plate of either similar or dissimilar materials with enhanced mechanical and metallurgical properties. Generally, welding is a multi-input and multi-output process in which there exists a close relationship between the quality of joints and the welding parameters. In the present study, Artificial Neural Network (ANN) has been used to predict the strength behavior of FWTPET process. Several Neural Network architectures have been subjected to analysis and the optimal architecture has been determined. The optimal architecture has been used to predict the output process parameter. The predicted output and input parameters have been optimized using Genetic Algorithm (GA). GA optimized and experimentally determined process parameters were compared and the deviation is found to be minimal. Besides, the most influential process parameter has been determined using statistical analysis of variance (ANOVA).     

Agile product development through CAD and rapid prototyping technologies: an examination in a traditional pump-manufacturing company

The pump industry is the one which is yet to exhibit agile characteristics by evolving new models quickly in accordance with the dynamic demands of the customers. The researchers have not yet explored the potential of infusing agile characteristics in the pump industry. In order to initiate exploration in this direction, the research reported in this paper was carried out. To begin with, the empirical equations used for designing the pump components namely impeller and casing were referred. Subsequently, a software to compute the parameters using these empirical equations was developed. By inputting these parameters in a Pro/E software package, four new solid models of impeller and casing were designed. These newly designed models were subjected to analysis using GAMBIT and FLUENT software packages. Subsequently, rapid prototyping technology was adopted to develop the prototype of one of those models of impeller. In order to obtain the industry view of this research, four practicing experts were approached with a questionnaire to gather their reactions. The results of their reactions indicated that this research could be practically applied to achieve agile product development through the interfacing of computer-aided design (CAD) and rapid prototyping technologies.     

Comparative study of composite membranes from nano‐metal‐oxide‐incorporated polymer electrolytes for direct methanol alkaline membrane fuel cells

A series of six composite membranes was prepared with two polymer electrolytes and three inorganic fillers, namely, silica, titania, and zirconia by a solution casting method. Two polymer electrolytes, that is, anion‐exchange membranes, were prepared from polystyrene‐block‐poly(ethylene‐ran‐butylene)‐block‐polystyrene (PSEBS) and polysulfone by chloromethylation and quaternization. A preliminary characterization of the ionic conductivity, methanol permeability, and selectivity ratio was done for all of the prepared composite membranes to check their suitability to work in direct methanol alkaline membrane fuel cells (DMAMFCs). The DMAMFC performance was analyzed with an in‐house fabricated single cell unit with a 25‐cm² area. Maximum performance was achieved for the composite membrane quaternized PSEBS/7.5% TiO₂ and was 74.5 mW/cm² at 60°C. For the comparison purposes, a commercially available anion‐exchange membrane (Anion Membrane International‐7001) was also investigated throughout the study. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Thirty criteria based leanness assessment using fuzzy logic approach

Nowadays manufacturing organizations are moving towards lean practices to keep pace with the competition. Lean practices mainly focuses on eliminating seven deadly wastes, thereby reducing the cost. Leanness is the measure of lean manufacturing practices. This paper presents the 30 criteria based leanness assessment methodology using fuzzy logic. Fuzzy logic has been used to overcome the disadvantages with scoring method such as impreciseness and vagueness. During this research, a conceptual model for leanness assessment has been designed. Then the fuzzy leanness index which indicates the leanness level of the organization and fuzzy performance importance index which helps in identifying the obstacles for leanness has been computed. The results indicate that the model is capable of effectively assessing leanness and has practical relevance.