International Journal of Six Sigma and Competitive Advantage (17 papers in press)
Deploying Lean Six Sigma framework in a healthcare organisation: a case experience
by Vikas Swarnakar, A.R. Singh, Anil Kr Tiwari
Abstract: Healthcare organisations have struggled with service quality problems to achieve operational excellence. Redundant waiting of patients is scathing to throughput and sustain organisations in a competitive environment. This study utilised a structured Lean Six Sigma DMAIC approach to reduce patient waiting time and improve service quality through systematic analysis of the problem of gynecology and obstetrics department of a multinational hospital. The structured implementation of the LSS framework was observed significant improvement in different aspects. The outcomes of the study revealed that 117% improvement in patient waiting time was observed for already appointed patients on weekdays whereas 68% in the case of arrived patients on Saturdays only. Further, 90% improvement was observed for walk-in patients who arrived on weekdays whereas 65% in the case of patients arrived on Saturdays only. The improvements were also calculated in terms of benefits, the average profit per year calculated as INR 36,939,600 that leading to an anticipated INR 292,981,025 by 2028. The findings of this study encourage researchers, practitioners, and decision-makers to employ the same method in other healthcare organisations to achieve the benefits.
Keywords: Lean Six Sigma; LSS; service quality; healthcare organisation; patient waiting time; bottom-line results.
Six Sigma-based RS, MDSS and MDSRS control charts
by Anna Zacharia, J. Ravichandran
Abstract: In this paper, well-defined Six Sigma-based repetitive sampling control charts (RSCCs) and multiple dependent state sampling control charts (MDSSCCs) are proposed. The Six Sigma-based multiple dependent state repetitive sampling control charts (MDSRSCCs) are also studied. The average run length (ARL) performance of the proposed charts are numerically evaluated and compared with the existing RSCCs, MDSSCCs and MDSRSCCs. Since the proposed charts are based on the Six Sigma methodology, these charts ensure the Six Sigma goal of 3.4 defects per million opportunities. It is observed that the proposed charts perform better than the existing ones by means of better average run lengths and also suggest minimum process disturbance for smaller shifts in the process mean. The charts are easier to apply by the quality practitioners. A numerical example is given to illustrate the better performance of the proposed control charts.
Keywords: average run length; multiple dependent state sampling; repetitive sampling; Six Sigma; zone control charts.
Effect of ergonomics on workers performance in Indian small scale industry
by Rohit Sharma, Parveen Sharma, Soyal Mohammed
Abstract: The workers daily work related problem is becoming musculoskeletal condition in India. As of now, the research is being carried out physically in the majority of small and medium enterprises along these lines, the problems of business-related musculoskeletal clutters and injury in different body locations are of major concern. Postural examination tool utilising REBA is connected for evaluation which demonstrates that the workers are working
over as far as possible. The investigation was conducted on 30 employees working in the small-scale industry. Subsequently it was inferred that; there is an absence of ergonomics mindfulness and comprehension in the small scale enterprises. Assessment utilising postural examination REBA demonstrates that the specialists are working over as far as possible. The working level of the workers are having very clumsy stances. Therefore the workers were told not to be in a bad posture and change their postures in order to get rid of musculoskeletal problems.
Keywords: ergonomics; small scale industry; posture analysis; rapid entire body assessment; REBA.
Contemplation of food industry attributes confronted in smooth adoption of Lean Six Sigma practices
by Janpriy Sharma, Mohit Tyagi, Dilbagh Panchal, Ravi Pratap Singh
Abstract: Food industries feed the lives on earth for survival and have significant importance in the economy of the country too. Globalisation, the growing population across the world, has increased the demand for food commodities, and industries are burdened with the pressure of high production volumes of quality products. Hence, the need of the hour becomes that industries should deploy various quality improvement initiatives like Lean Six Sigma (LSS), to improve their production practices and outputs with increased profitability. Food industries are quite different from other manufacturing industries, in terms of product type, processes, procurement and distribution channels, etc. Likewise, the deployment of LSS principles in food industries is also monitored by its special attributes. These attributes must be identified before the successful implementation of LSS in food industries. This work identifies those unique attributes of food industries that act as barriers to the smooth deployment of LSS. The identified attributes are further analysed by the tool of GREY Decision-Making Trial and Evaluation Laboratory (DEMATEL). The results from this study enable the industry to curb the attributes which are causing the barrier in implementing LSS. For checking the robustness of the generated results, sensitivity analysis is carried out.
Keywords: Lean Six Sigma; LSS; food industry; GREY – DEMATEL; barriers in Lean Six Sigma; Indian food industry.
Multi-objective optimisation and analysis of fused deposition modelling parameters: best infill patterns
by Pooja Patil, Dharmendra Singh, Sunil Jaysing Raykar, Jaipraksh Bhamu
Abstract: Components manufactured with additive manufacturing process are always exceptional with respect to their quality in terms of shape and size. Fused deposition modelling (FDM) is one 0f the additive manufacturing process used to manufacture high quality polymer components and prototypes. Quality of parts manufactured by FDM depends on many of its process parameters like infill %, layer thickness, bee temperature, infill percentage, speed, and infill patterns. This paper presents a multi-objective optimisation paradigm based on VIKORAHP for selection of best printing parameters for FDM. Layer thickness of 0.3 mm, 80 mm/s of printing speed, 50% of infill % with zig-zag pattern gives the best results in terms of FDM performance. With these settings printing times is 22 min with consumed filament length and weight are 2.25 m and 6.72 gms respectively.
Keywords: additive manufacturing; fused deposition modelling; FDM; infill pattern; optimisation; vise kriterijumska optimizacija i kompromisno resenje VIKOR; analytical hierarchy process; AHP.
Estimation of best possible solutions for environmental trade-offs in cold supply chain using BWM based ELECTRE-I approach
by Neeraj Kumar, Mohit Tyagi, Anish Sachdeva
Abstract: Present research work aimed to establish an environmental trade-off between energy consumption and product life cycle in cold supply chain (CSC). For the same, the authors have focused on consolidating the various issues liable to a higher rate of negative emissions from the cold chain (CC) and exploring the best-suited alternatives promising to lower the environmental impact of the same. To establish the theoretical framework and ground the empirical aspects of the analysis, the research work recognised five most influencing environmental criteria of CSC and proposed six most preferable alternatives to mitigate the negative influence of criteria on the environment. In order to acquire the objective, the best worst method (BWM) and ELECTRE-I approach has been used. The outcomes of the paper highlight that the energy consumption and GHG emissions per unit of cooling load are the two most severe criteria of the CC from an environmental perspective.
Keywords: cold supply chain; perishable products; environmental load; electre method; BWM method; carbon emission; refrigeration.
A case study on the DMAIC Six Sigma application to prevent injuries in the manufacturing industry
by Rohit Kenge, Zafar Khan
Abstract: Ever growing rivalry and non-standard customer requirements triggered a continuous improvement need at goods manufacturing. The injury at workstations to the operators increases the actual lead time of the delivery to the final customer. This paper works on the DMAIC Six Sigma applications to reduce the injury due to burr formation while hammering in the tractor transmission manufacturing. We applied hypothesis testing, DOE, and Z test ANOVA to check the two variables relation with each other and effects of improvement actions over the process at the workstations. We applied cause and effect diagram and matrix, and FMEA that given 15 probable input variables X for the improvement. We applied the improvement actions over these Xs and verified the process capability that found Ok. Finally, we reduced total injury from 2 to 0 nos/month against the target of the 0 incidents and RPN reduced from 343 to 96.
Keywords: DMAIC; Six Sigma; process capability; ANOVA; FMEA.
Implementation of Lean Six Sigma in industrial manufacturing applications: a case study
by Harkrit Chhatwal, Nishant Bhasin, Aditya Bassi, Shubham Sharma, Ruchika Gupta
Abstract: This paper presents a case study where the implementation of Lean Six Sigma tools in the inventory control and management of raw material were investigated to study its impact. During this investigation, the problem with large inventory levels and non-moving items were examined through the define, measure, analyse, improve and control (DMAIC) concept of Lean Six-Sigma. The study includes the analysis of the current system depicting the
existing problems within the company. The methodology aims to analyse the root cause of existing problems and then based on the root cause helps to design an improvement plan through proper process mapping. At the end of the investigation, a few solutions were proposed for implementation. The results demonstrates that with the steps taken to optimise the inventory, an increase in the inventory turnover ratio (ITR) by 33% from a level of 4 to an improved level of 6 can be achieved which will saved the inventory cost for sustainable use in future.
Keywords: inventory turnover ratio; ITR; cost of goods sold; COGS; day sales inventory; DSI; define; measure; analyse; improve and control; DMAIC.
Water budget control using DMAIC in commercial buildings
by Malek Almobarek, Abdallah Alrshdan
Abstract: This research is focused on one of the important water management schemes based on its budget control. The Six Sigma approach has been well implemented in an operational framework style to detect water budget deviation. The approach includes five phases: define, measure, analyse, improve, and control (DMAIC). The research recommended managerial steps in each phase that build a road map to implement the framework. The steps
contain several statistical and quality engineering tools, which are considered as pillars of the proposed framework. The commercial buildings are addressed and one of the universities was used as a case study to implement the framework. DMAIC has shown a valid outcome in finding the significant locations that effecting the allocated budget. In a particular period, three locations were found significant at the university case study and the framework led to the associated issues like leakage, broken faucet, and drain batteries washbasin.
Keywords: DMAIC; water; budget control; commercial buildings.
Evaluating reliability of diesel generator peakers using Six Sigma methodologies
by Salma Shaik, Scott Sampson, Matthew J. Franchetti
Abstract: This case study demonstrates the application of DMAIC process improvement methodology to improve the reliability of diesel generator peaker units when called into activation. Although the application of Six Sigma methodologies is commonplace in manufacturing industries, they lack the same level of adaptability in non-manufacturing processes and service industries especially in power generation sector. The main objective of the present case study is to address this gap by developing a thorough analytical framework that can be adapted to improve the reliability of peaker units in any business sector based on Six Sigma methodologies. Failure in control systems, temperature extremes, incorrect flagging of the unit as available were some of the major causes identified for the failure of peaker units.
Keywords: peakers; diesel generators; reliability; Six Sigma; process improvement; continuous improvement; design-measure-analyze-improvecontrol; DMAIC; case study.
Structural modelling and ranking the warehouse activities in a pharmaceutical supply chain system
by Shweta , Amit Kumar Yadav, Dinesh Kumar
Abstract: Storage and inventory management of drugs in a pharmaceutical industry is a complex process and it constitutes major part of costs, specifically when talking for the distribution of generic medicines. Therefore, warehouse management for generic medicine has to be looked from its basic concept for its design and operation. This article proposes a framework to redesign a warehouse for storage and distribution of generic medicines through exploratory case study. Field survey has been performed and bottleneck
involved in the warehouse of a pharmaceutical industry has been identified using interpretive structural modelling (ISM) and fuzzy analytical hierarchy process (FAHP). The decisions made in the process mainly depend upon the dynamics of the different activities involved and their interrelationships. ISM establishes interrelationships between different activities and FAHP prioritises most sluggish sub-activities of warehouse. The findings highlight that quality control activities are heavily responsible for bottlenecks.
Keywords: generic pharmaceutical supply chain; GPSC; fuzzy AHP; ISM; bottlenecks; interpretive structural modelling; analytical hierarchy process.
Barrier analysis for channel synchronisation and implementation of omni channel supply chain strategy meeting customer preferences
by T. Niranjan, P. Parthiban
Abstract: Omni channel is an approach that enables customer to shop across various platforms from brick-and-mortar stores to mobile app while offering them fully integrated shopping experience. The aim of this study is to identify the barriers and develop a path model discovering the strength and pattern of relationship among these barriers. The challenges that a firm would be facing while moving towards omni channel are explored by empirically testing a model. The structural equation modelling (SEM) technique is used for addressing these challenges which can help in future omni channel implementations. Results of this study shows that the challenges related to strategy are the greatest barriers in the initial stage of omni channel implementation while barriers related to development turn into the greatest barrier in the second phase. The obtained results give important guidelines to the multi-channel firms for streamlining their existing channels.
Keywords: omni channel; structural equation modelling; SEM; supply chain; barriers; strategy.
Solving production bottleneck through developed define-measure-delegate-implement-control in solving production bottleneck
by Muhammad Danish Mohamad Rosni, Mohd Norzaimi Che Ani, Ishak Abdul Azid, Shahrul Kamaruddin
Abstract: This study focuses on the development of a define-measuredelegate-implement-control (DMDIC) framework to solve production bottleneck where this issue causing the productivity to drop. The plan-docheck-act (PDCA) and define-measure-analyse-improve-control (DMAIC) approaches have been successfully employed in solving production issues, however each approach has its limitation to certain aspects, for example, both approaches dealing either short- or long-term solution. The PDCA approach normally proposes a short-term solution that is faster in achieving a result. While the DMAIC approach can propose a long-term solution that can find the main causes of the drop in productivity. Thus, this study introduces a newly developed framework on handling short- and long-term solution to improve production bottleneck. Based on the simulation results using DMDIC approach, the production daily output had significantly improved from 264 to 304 units which had met customer daily demand. This result showed that the developed framework could improve productivity, thereby meeting customers requirements.
Keywords: PDCA; DMAIC; DMDIC; unit per hour; UPH; productivity.
Sustainable continuous improvement programs
by Liem Ferryanto
Abstract: Continuous Improvement programs in their various forms have proven their capabilities in creating value for a company, but often fail to have a lasting impact. The reason is its management and engineers gradually lose incentive and fall back into longstanding ways because they fail to consistently meet their objectives, solving ill-posed inverse problems. The unsustainable executions and results are costly and take more unnecessary time for the company to attain high return on investment. This article examines three key
tenets of the continuous improvement programs, i.e., deployment, methodology, and common tool. Behavioural economics approach, scientific principles, and causal inferences based on Bayesian statistics are applied to guide us in evaluating the key tenets. The guidance is used to extract the prerequisites of the mindset development of understanding and improving the mechanism of the true causality and reasoning process to uphold continuous improvement intended goals, i.e., perpetually better quality, and capability improvement.
Keywords: Bayesian inferences; behavioural economics; cognitive biases; hypothesis testing and p-value; ill-posed problems; lean; learning mindset; Six Sigma; scientific principles.
Understanding LSS 4.0 through golden circle model and reviewing its scope in Indian textile industry
by Ashwani Sharma, Bikram Jit Singh
Abstract: Industry 4.0 renders a smart factory by using sophisticated information and communication systems along with forward-looking technologies. This paper analyses the incompletely understood link between Industry 4.0 and Lean Six Sigma (LSS) as far as quality excellence is concerned. It explores whether Industry 4.0 tools, synergised with LSS strategies, can bring performance excellence in 21st century manufacturing systems. Further, the scope and applicability of LSS 4.0 approach in Indian textile industries have been reviewed and explored for bringing a paradigm shift in this domain. LSS 4.0 is rarely applied in Indian textile cluster and this paper will definitely enhance the concerned knowledge base. Golden circle approach will make the idea more systematic and easy to understand.
Keywords: TQM; Lean; Six Sigma; Lean Six Sigma; LSS; Industry 4.0 tools.
Role of employee training on Six Sigma implementation success: an empirical study
by Anthony Bagherian, Mark Gershon, Vikas Swarnakar
Abstract: According to a study by distinct authors, nearly 60% of all corporate Six Sigma initiatives fail due to various and, nonetheless, inaccurate SS training provided to employees. The objective of this study is to investigate what elements of employee training contribute to the success of Six Sigma initiatives in the automotive industry. The present study used an explorative research questionnaire and approaches using a mixed-method research design. The study identified three essential key elements of training: 1) learning how to use the essential DMAIC tools; 2) appropriate use of metrics (PPM and Sigma level); 3) new employees should be trained in the utility of DMAIC. The practical implications of this study would support the institution, and practitioners, in incorporating these three elements into their employee training. This paper is an original contribution to the analysis of key elements of employee training in the automotive industry in Europe.
Keywords: Six Sigma; employee training; success factors; survey; factor analysis; automotive industry.
A Six Sigma and DEA approach for learning outcomes assessment at industrial engineering programs
by Enrique Delahoz-Dominguez, Rohemi Zuluaga-Ortiz, María Suarez-Sánchez
Abstract: This research assesses the performance of 89 industrial engineering degrees in Colombia. The proposed approach articulates the Six Sigma concept of quality with the efficiency assessment from data envelopment analysis. The data used correspond to the standardised test taken by university students in Colombia in their last year of training (SABER_PRO). The input variables used for the Six Sigma metrics are quantitative reasoning, critical reading, citizen competencies, English and written communication. The output variable is the learning outcome, formulation and evaluation of projects. The studys findings show that universities with institutional quality accreditation have a higher level of compliance than non-accredited universities. Also, private universities have a higher level of compliance than public universities. Regarding the data envelopment analysis model results, the average level of efficiency of the universities determined by the CRS, VRS, and performance to scale models is 93%, 90%, and 92%, respectively.
Keywords: Six Sigma; data envelopment analysis; DEA; predictive evaluation; higher education.