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Lean thinking (LT) has been implemented in various manufacturing and service sectors. But, only a few published research articles have developed a framework describing the procedure for implementing LT in an educational institute. The purpose of this paper is to develop and demonstrate a framework that can provide a structured procedure for the implementation of LT in an educational institute.

Various LT tools and techniques applicable in educational institute were identified by reviewing the relevant literature. By adopting an action research methodology (ARM) for a time period of 28 months, the processes in a case institute were studied; wastes in the process were identified and various solutions were proposed and implemented.

A comparison of the performance measures before (Batch 1) and after (Batch 2) implementation of solutions provided interesting insights into the effectiveness of LT. In both the batches, absenteeism in the class was found to increase across the terms. But the magnitude of increase was lesser in Batch 2. Results also showed that the number of unfilled seats (poor utilization) in an elective course in the second year of the program drastically reduced in Batch 2. Finally, a framework that can guide LT implementation in educational institutes was proposed.

The current study describes only the initial stages of implementation in an educational institute. Hence, some of the benefits discussed are expected in the long run which can be assessed by carrying out a longitudinal study. Future study can attempt to empirically validate the proposed framework in multiple educational institutes and theoretically explain the reasons behind the results obtained.

ARM can be used as a tool by practitioners to study the behavioral aspects of employees of educational institutes toward LT implementation. The proposed framework and its demonstration can assist employees in educational institutes to implement LT. Positive results obtained in this study can further motivate the educational institutes to consider LT as a potential tool for improving the processes.

This is the first study to develop and validate a framework for structured implementation of LT in the processes of an educational institute. The study is also unique in empirically capturing the impact of LT implementation of an educational institute by analyzing the archived data.

The purpose of this work is to gain insights about Lean Six Sigma (LSS) in the Indian context by reviewing the related literature for one decade based on various perspectives, such as author profile, year of publication, type of firm, type of methodology used, type of industry for which the research work is carried out and the key findings from the research.

This study reviews the research related to LSS from the articles published in the reputed journals. The literature used for reviewing is derived from the sources, including Science direct, Google scholar, IEEE, Taylor and Francis Group, Emerald Insight, Springer, Inderscience and Elsevier during the period between 2010 and 2021. Totally, the authors have included 141 LSS-related research articles that are published in the Indian context. The keywords used are Lean Six Sigma, Lean Six Sigma in the Indian context, Lean Sigma and LSS to identify and consolidate the research papers published during this timeframe.

The research papers collected from various reputed journals, including Scopus and non- Scopus enlisted, are classified and grouped under various categories to identify the class of author who publishes more in this field, research trend over the years, the type of firm which implements LSS, the research methodology which is commonly used in LSS and related research and also the key takeaway from these articles are highlighted. Further, the authors have also identified the major contributions of researchers in various sectors during this period in India.

This classification framework and the systematic review help in identifying the research gap and in giving directions for future researchers. It will be useful for researchers and practitioners working on the area of LSS, rural and urban entrepreneurs, start-up managers, professionals working in micro, small and medium enterprises (MSMEs) and executives of the Make in India Project to make India as Aatmanirbhar Bharat Abhiyan. Further, the clear direction of progress over the current decade in manufacturing industries, service sectors and processing industries can help the professionals working in these sectors.

This research aims to conduct a literature review of Lean Six Sigma (LSS) in the Indian context and related research publications and apply bibliometric analysis and the author's visualization to map research trends in this area.

This article conducts a bibliometric analysis of LSS-related research in the Indian context using data gathered from Scopus and Web of Science databases from 2011 to 2022. The review provides information on LSS-related research in the Indian context and evaluates performance based on primary sources, authors, keywords, countries, affiliations, and documents. The analysis employs the Biblioshiny app and Bibliometrix R-tool for data analysis and scientific mapping.

The results of the bibliometric analysis indicate that the LSS culture has widely spread in India. The International Journal of Lean Six Sigma and Production Planning and Control were found to be the most productive sources for publishing LSS-related research articles. Antony J. was identified as the most active author in this field, contributing the most over the years. Among all organizations, NITs have conducted the most comprehensive research on LSS, indicating their significant investment of resources and efforts in studying this methodology and its applications in India. Additionally, the study examined the intellectual, social, and conceptual structures to identify implicit gaps and future research opportunities.

The findings of this study can inform academicians, researchers, practitioners, and policymakers about the state-of-the-art and the specifics of the most prolific studies. This study will facilitate their exploration of emerging research areas in LSS.

To the best of the authors knowledge, this is the first bibliometric analysis of LSS in the Indian context, providing an overview of relevant publications published between 2011 and 2022. This study analyzed 194 articles on LSS in India, which can help researchers and academics identify emerging research areas, suitable collaborators, and relevant journals for future publications.

The purpose of this research paper is to optimize the process parameters of selective laser sintering process, and the sintered parts of PA2200 prototypes are built with minimum surface roughness within the range of 10-12 microns using the Taguchi design of experiments approach.

In this research paper, a 3D model is created using catia V5 and exported to rapid prototype machine, and the 3D model file was repaired by using Magics software to remove the facets and saved with file extension .stl (standard triangulation language).Taguchi design of experiments approach L9 orthogonal array was selected with three factors at three levels each and total nine experiments were conducted with the quality index lower-the-better signal-to-noise ratio to produced better quality prototypes by optimizing the process parameters like laser power, layer thickness and temperature and tested on surface tester for surface roughness. The experimental results of surface roughness were compared with Regression Analysis, S/N Ratio, Analysis of Mean and predicted model on sintered prototypes.

The experimental results obtained after testing on the surface tester compared with mathematical model for the quality index lower-the-better signal-noise ratio with optimal process parameters operating at Temperature at level 3, Layer thickness at level 3, and Laser power at level 3, regression analysis, and predictive model the output response variable surface roughness, is with in the range of 9-10.5 microns are all most same and from ANOM (Analysis of Mean), temperature at leve1, layer thickness at level 2, laser power at level 2 is 9 -9.6 microns.

The process parameters such as beam diameter and table speed were not considered on output response variable surface roughness in this research paper.

All the experiments were conducted and the parts are produced by using the material PA2200 in the powder from and sintered by Co₂ laser by varying the process parameters with optimal settings to produce minimum surface roughness the out put from this paper is the influence of process parameters on surface roughness can be predicted at optimal settings with in less time and cost.

Liquid crystal display (LCD)-based stereolithography (SLA) technique has been used in drug delivery and fabrication of microfluidic devices and piezoelectric materials. It is an additive manufacturing technique where an LCD source has been used as a mask to project the image onto the tank filled with photo curable resin. This resin, when interacted with light, becomes solid. However, critical information regarding the energy absorption during the compression analysis of different components three-dimensional (3D) printed by SLA process is still limited. Therefore, this study aims to investigate the effect of different process parameters on the compressive properties.

In the present study, the influence of layer thickness, infill density and build orientation on the compression properties is investigated. Four infill densities, that is, 20%, 40%, 60% and 80%; five-layer thicknesses, that is, 50 µm, 75 µm, 100 µm, 150 µm and 200 µm; and two different orientations, that is, YXZ and ZXY, have been selected for this study.

It is observed that the samples printed with acrylonitrile butadiene styrene (ABS) absorbed higher energy than the flexible polyurethane (FPU). Higher infill density and sample oriented on ZXY absorbed higher energy than sample printed on YXZ orientation, in both the ABS and FPU materials. Parts printed with 80% infill density and 200 µm layer thickness resulted into maximum energy for both the materials.

In this study, two different types of materials are used for the compression analysis using LCD-SLA-based 3D printer. Specific energy absorbed by the samples during compression testing is measured to compare the influence of parameters. The investigation of infill parameters particularly the infill density is very limited for the SLA-based 3D printing process. Also, the results of this study provide a database to select the print parameters to obtain the required properties. The results also compare the specific energy for hard and flexible material for the same combination of the process parameters.

Stereolithography (SLA) is a broadly used technology in the field of rapid prototyping. One of the disadvantages of SLA is poor mechanical properties of its products. To approach the mechanical properties of original part, the mechanical properties of SLA part, such as tensile strength, should be optimized. In this process, there are many parameters that affect the tensile strength of parts. However, the “layer thickness”, “fabrication orientation” and “post curing time” are the most significant ones. Hence, the purpose of this study is to investigate the influence of these parameters on tensile strength of SLA parts.

According to the obtained results from experiments based on the “full factorial” method, an empirical equation was developed for the tensile strength in terms of the effective parameters by using regression analysis. Considering this empirical equation, the process parameters were optimized to maximize the tensile strength by using genetic algorithm. Finally, the tensile tests of the specimens were simulated via the general-purpose finite element package of ABAQUS.

The outputs of the numerical simulations were in good agreement with experimental results. Both experimental and numerical results show that the increase of layer thickness and the decrease in post curing time increase the tensile strength. Furthermore, the tensile strength of parts produced in vertical orientation is higher than that of parts produced in horizontal orientation.

This is a complete study about the tensile strength of the SLA parts from experimental and analytical viewpoints.

Masked stereolithography (MSLA) or resin three-dimensional (3D) printing is one of the most extensively used high-resolution additive manufacturing technologies. Even though, the quality of 3D printing is determined by several factors, including the equipment, materials and slicer. Besides, the layer height, print orientation and exposure time are important processing parameters in determining the quality of the 3D printed green state specimen. The purpose of the paper is to optimize the printing parameters of the Masked Stereolithography apparatus for its dimensional correctness of 3D printed parts using the Taguchi method.

The acrylate-based photopolymer resin is used to produce the parts using liquid crystal display (LCD)-type resin 3D printer. This study is mainly focused on optimizing the processing parameters by using Taguchi analysis, L-9 orthogonal array in Minitab software. Analysis of variance (ANOVA) was performed to determine the most influencing factors, and a regression equation was built to predict the best potential outcomes for the given set of parameters and levels. The signal-to-noise ratios were calculated by using the smaller the better characteristic as the deviations from the nominal value should be minimum. The optimal levels for each factor were determined with the help of mean plots.

Based on the findings of ANOVA, it was observed that exposure time plays an important role in most of the output measures. The model’s goodness was tested using a confirmation test and the findings were found to be within the confidence limit. Also, a similar specimen was printed using the fused filament fabrication (FFF) technique; it was compared with the quality and features of MSLA 3D printing technology.

The study presents the statistical analysis of experimental results of MSLA and made a comparison with FFF in terms of dimensional accuracy and print quality.

Many previous studies reported the results based on earlier 3D printing technology such as stereolithography but LCD-based MSLA is not yet reported for its dimensional accuracy and part quality. The presented paper proposes the use of statistical models to optimize the printing parameters to get dimensional accuracy and the good quality of the 3D printed green part.

In-situ aluminum metal matrix composites (AMMC) have taken over the use of ex-situ AMMC due to the generation of finer and thermodynamically stable intermetallic compounds. However, conventional processing routes pose inevitable defects like porosity and agglomeration of particles. This paper aims to study current state of progress in in-situ AMMC fabricated by Friction Stir Processing.

Friction stir processing (FSP) has successfully evolved to be a favorable in-situ composite manufacturing technique. The dynamics of the process account for a higher plastic strain of 35 and a strain rate of 75 per second. These processing conditions are responsible for grain evolution from rolled grain → dislocation walls and dislocation tangles → subgrains → dislocation multiplication → new grains. Working of matrix and reinforcement under ultra-high strain rate and shorter exposure time to high temperatures produce ultra-fine grains. Do the grain evolution modes include subgrain boundaries → subgrain boundaries and high angle grain boundaries → high angle grain boundaries.

Further, the increased strain and strain rate can shave and disrupt the oxide layer on the surface of particles and enhance wettability between the constituents. The frictional heat generated by tool and workpiece interaction is sufficient enough to raise the temperature to facilitate the exothermic reaction between the constituents. The heat released during the exothermic reaction can even raise the temperature and accelerate the reaction kinetics. In addition, heat release may cause local melting of the matrix material which helps to form strong interfacial bonds.

This article critically reviews the state of the art in the fabrication of in-situ AMMC through FSP. Further, FSP as a primary process and post-processing technique in the synthesis of in-situ AMMC are also dealt with.