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This paper aims to focus on the application of multi-attribute decision-making methods (MADMs) to ascertain the optimal machining parameters while turning Ti-6Al-4V alloy under minimum quantity lubrication (MQL) conditions using Jatropha-curcas oil (JCO) bio-based lubricant.

The experiments were designed and performed using Taguchi L27 design of experiments methodology. A total of 27 experiments were performed under MQL conditions using textured carbide cutting tools on which different MADMs like Analytic hierarchy process (AHP), Technique for order preference by similarity to ideal solution (TOPSIS) and Simple additive weighting (SAW) were implemented in an empirical manner to extract optimize machining parameters for turning of Ti-6Al-4V alloy under set of constrained conditions.

The results evaluated through MADMs exhibit the optimized set of machining parameters (cutting speed V_c = 80 m/min, feed rate f = 0.05 mm/rev. and depth of cut a_p = 0.10 mm) for minimizing the average surface roughness (Ra), maximum flank wear (Vbmax), tangential cutting force (Fc) and cutting temperature (T). Further, analysis of variance (ANOVA) and traditional desirability function approach was applied and results of TOPSIS and SAW methods having optimal setting of parameters were compared as well as confirmation experiments were conducted to verify the results. A SEM analysis at lowest and highest cutting speeds was performed to investigate the tool wear patterns. At the highest speed, large cutting temperature generated, thereby resulted in chipping as well as notching and fracturing of the textured insert.

The research paper attempted in exploring the optimized machining parameters during turning of difficult-to-cut titanium alloy (Ti-6AL-4V) with textured carbide cutting tool under MQL environment through combined approach of MADMs techniques. Ti-6Al-4V alloy has been extensively used in important aerospace components like fuselage, hydraulic tubing, bulk head, wing spar, landing gear, as well as bio-medical applications.

The purpose of this study is to recognize critical barriers for Lean manufacturing practices implementation in small and medium enterprises (SMEs) focusing in the context of a developing economy. The advancement of SMEs is of utmost important for a surge in exports while competing with other countries and these barriers have to be given due importance as they play a major role in stalling the overall development of SMEs.

In this present investigation, 26 barriers to Lean implementation in SMEs have been identified after an extensive study of the literature available on the subject. After that, the influential barriers were investigated through the Analytical hierarchy process-Technique of order preference by similarity to ideal solution (AHP-TOPSIS) method using priority weightage given to them by different experts in their industries. The ranking given to the barriers is based on the AHP-TOPSIS method and has been validated by the sensitivity analysis.

The investigation reveals that for the successful implementation of Lean manufacturing practices, the will of the management, individual will power and contribution of the people matter a lot apart from other barriers such as flexibility, expertise of the people, resources and resistance offered by the people to new programs. The solutions for overcoming these barriers are also provided in this study and a model has been suggested for the same.

This work was devoted to the evaluation of obstacles in the introduction of Lean practices and prioritizing them. But it was limited to the medium- and small-scale organizations located in Northern India. Further studies can expand the scope to the large-scale units in the field. Moreover, the scope of this study was confined to the manufacturing sector. Future studies can extend it to the non-manufacturing environments such as the service sector, health care, etc. This investigation was based on the judgments of industry experts and academicians. Another approach such as Viekriterijumsko kompromisno rangiranje can be used for future investigations.

This study is significant when keeping in mind the contribution of SMEs to a country’s economy, especially in the Indian context.

Hemisphericity in behaviour studies is the role and dominance of right bran/left brain in the human brain, each side of which has varying roles and characteristics, thereby leading to different thinking orientations in the human. A study was conducted to measure the hemisphericity orientation of construction and design engineers in a large public construction organization. We know from literature that people of different hemisphericity orientations have unlike personalities and dissimilar perspectives of specific situations. The essential characteristics of hemisphericity as established in literature are presented and used in analysing the organization. From this study of engineers, it was seen that construction engineers in the organization, State Department of Engineering Construction (SDEC), are predominantly left‐brained while design engineers are predominantly right‐brained. This difference in orientation partially explains why the design and construction engineers at SDEC are unable to see eye‐to‐eye in issues concerning implementation of drawings. Left hemisphere dominant engineers are also seen to desire more organizational changes than their right hemisphere dominant counterparts. Ideally, researchers believe that a 50–50 distribution of hemisphericities in large organizations is desirable. Details, analysis, and recommendations are presented in the paper.

The purpose of this paper is to fabricate acrylonitrile-butadiene-styrene (ABS)/high impact polystyrene (HIPS) based multi-material geometries using a low cost polymer printer. At the same time, efforts have been made to investigate the mechanical characteristics of the obtained prints and to perform the optimization using the Taguchi-Grey (TGRA) method.

Initially, the feedstock materials were in-house fabricated in the form of filament wires, workable with fused filament fabrication (FFF) technique, of 1.75 ± 0.1 mm diameter by using a single screw extruder. Multi-material structures were fabricated using variable parameters (such as: raster angles, layer height, fill density and solid layers) and the experimentation was conducted as per Taguchi L18 array. Mechanical responses obtained by performing tensile, impact and bending test were studied in response to input variables and ultimately optimized settings were obtained, for individual as well as multiple parameters). Scanning electron microscopy (SEM) analysis was performed to analyze the fractured surfaces.

The Signal/Noise (S/N) plots for the quality characteristics highlighted that selected input parameters significantly influenced the obtained values for tensile strength, impact strength and flexural strength. Micrographs of the fractured specimens showed the occurrence of brittle fracture with higher levels of perimeter, infill density and solid layers. The extent of delamination was also increased under the bending load and further increased by increasing solid layers.

The results of the study strongly advocated the utility of fabricated multi-materials structures in automotive, aerospace and other manufacturing industries.

This work represents the fabrication, testing and analysis of polymer-based multi-material structures for engineering applications.

Delivering premium services and quality products are critical strategies for success in manufacturing. Continuous improvement (CI), as an underlying foundation for quality management, is an ongoing effort allowing manufacturing companies to see beyond the present to create a bright future. We propose a novel integrated fuzzy framework for analyzing the barriers to the implementation of CI in manufacturing companies.

We use the fuzzy failure mode and effect analysis (FMEA) and a fuzzy Shannon's entropy to identify and weigh the most significant barriers. We then use fuzzy multi-objective optimization based on ratio analysis (MOORA), the fuzzy technique for order of preference by similarity to ideal solution (TOPSIS) and fuzzy simple additive weighting (SAW) methods for prioritizing and ranking the barriers with each method. Finally, we aggregate these results with Copeland's method and extract the main CI implementation barriers in manufacturing.

We show “low cooperation and integration of the team in CI activities” is the most important barrier in CI implementation. Other important barriers are “limited management support in CI activities,” “low employee involvement in CI activities,” “weak communication system in the organization,” and “lack of knowledge in the organization to implement CI projects.”

We initially identify the barriers to the implementation of CI through rigorous literature review and then apply a unique integrated fuzzy approach to identify the most important barriers based on the opinions of industry experts and academics.

The study aims at empirically investigating and prioritizing the critical barriers for the successful implementation of agile manufacturing in the medium- and large-scale Indian manufacturing industries.

A literature review of peer-reviewed journals and discussion with experts is used to identify 17 barriers to the implementation of agile manufacturing. An empirical survey is then conducted to collect data regarding the agile manufacturing barriers and is further analyzed using the factor analysis and vlsekriterijumska optimizacija i kompromisno resenje (VIKOR).

Based on the survey of empirical data, the investigated critical barriers were reduced in five critical categories, as follows: Managerial constraints, technological constraints, human resource–related constraints, operational constraints and organizational culture-related constraints, which are further ranked in terms of their severity using VIKOR. This research advocates the development of a strategy for addressing the most critical barriers instead of focusing on all for the successful implementation of agile manufacturing.

This work contributes to agile manufacturing literature by the structured presentation of the barriers to implement agile manufacturing in the Indian manufacturing industry. It also extends the integrated factor analysis and VIKOR method to investigate and rank the barriers.

The thermoplastic polymers do not decompose easily due to the presence of long-chain stable polymeric structure, and thus, causes serious effects on the environment. Recycling of these polymer wastes becomes the only solution to minimize their adverse effects on the environment. The purpose of this study was to explore the feasibility of using recycled thermoplastic material as filament for fused deposition modeling technique.

In this study, the researchers fabricated fused filaments (in-house) for fused deposition modeling (FDM) technique of additive manufacturing from secondary recycled acrylonitrile butadiene styrene (ABS) by using a twin-screw extruder. After measuring the melt flow index of the secondary recycled ABS, the twin-screw extrusion parameters (rpm/speed of the screw, extrusion temperature and load) were varied to predict their influence on the various properties (rheological/mechanical/thermal) of the fabricated filaments. Experimental work was executed as per Taguchi’s L9 orthogonal array.

Thermal analysis performed to estimate the heat carrying capacity of recycled ABS highlighted that the heat capacity of ABS increases significantly from 0.28 J/g to 3.94 J/g during the heating cycle. The maximum value of peak strength and percentage break elongation for the fused filaments was investigated at 12.5 kg load, 2,250 C extrusion temperature and 70 rpm speed.

The filaments fabricated by recycling the polymeric waste has been successfully used in the FDM machine for the preparation of the three-dimensional printed tensile specimen.

The aim of this paper states that total productive maintenance (TPM) is an improvement tool which employs the effective utilization of employees in order to enhance the reliability of the equipment in consideration.

This paper identifies and evaluates the factors accountable for the adoption of TPM methodology in manufacturing organizations. Twenty-four factors affecting the TPM implementation are explored and categorized into five significant categories. Afterwards, these identified TPM factors have been evaluated by using a most popular Multi-criteria decision-making (MCDM) approach namely fuzzy pivot pairwise relative criteria importance assessment (F-PIPRECIA).

In this paper, through application of F-PIPRECIA, “Behavioural factor” is ranked first while “Financial factor” the last. Considering the sub-factors, “Top management support and commitment” is ranked first while “Effective use of performance indices” is ranked the last. A further sensitivity analysis indicates the factors that need higher level of attention.

The result of current research work may be exploited by the top administration of manufacturing enterprises for assessing their TPM adoption status and to recognize the frail links of TPM application and improve accordingly. Moreover, significant factors of TPM can be identified and deploy them successfully in their implementation procedure.

The conclusion obtained from this research enables the management to clearly understand the significance of each considered factor on the adoption of TPM in the organization and hence, provides effective utilization of resources.

Mindfulness is the practice of focusing attention effectively/purposefully, in a non‐judgemental manner, on current circumstances (Kabat‐Zinn, 2009; Crane, 2009). It has been increasingly used as a tool for managing a range of difficulties associated with personal suffering, including stress and chronic pain, as well as some aspects of mental disorder. In this study the practice of mindfulness was introduced to a medium secure ward for female patients with learning disabilities in the form of twice‐weekly, 30‐minute group sessions. Proxy measures of institutional aggression namely the number of observations (Obs), physical interventions (PI), and seclusions (Sec) were recorded at baseline (during the month prior to the introduction of the mindfulness sessions and at two months and six months following the introduction of the sessions). Friedman's Analysis of Variance and post‐hoc analyses using Wilcoxon's Signed Ranks showed a significant reduction at six months. The potential influence of basic mindfulness practice sessions in reducing aggression is discussed.

The purpose of this paper is to fabricate pre-existing geometries of the stents using solvent cast 3D printing (SC3P) and encapsulation of each stent with heparin drug by using aminolysis reaction.

The iron pentacarbonyl powder and poly-ɛ-caprolactone blend (PCIP) were used to print stent designs of Art18z, Palmaz-Schatz and Abbott Bvs1.1. The properties of antithrombosis, anticoagulation and blood compatibility were introduced in the stents by conjugation of heparin drug via the aminolysis process. The aminolysis process was confirmed by energy dispersive X-ray spectroscopy and Fourier transform infrared spectroscopy due to presence of amide group and nitrogen peak in the respective analysis. Biological studies were performed to depict the cell viability, hemocompatibility and antithrombotic properties. Besides, mechanical behaviors were analyzed to study the behavior of the stents under radial compression load and bending load.

The amount of heparin immobilized on the Art18z, Palmaz-Schatz and Abbott Bvs1.1 stents were 255 ± 27, 222 ± 30 and 212 ± 13 µg, respectively. The cell viability studies using L929 fibroblast cells confirmed the cytocompatibility of the stents. The heparinized SC3P printed stents displayed excellent thrombo-resistance, anticoagulation properties and hemocompatibility as confirmed by blood coagulation analysis, platelet adhesion test and hemolysis analysis. Besides, mechanical behavior was found in context of the real-life stents. All these assessments confirmed that the developed stents have the potential to be used in the real environment of coronary arteries.

Various customized shaped biodegradable stents were fabricated using 3D printing technique and encapsulated with heparin drug using aminolysis process.