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This article focuses on the comparative study of annular wire‐coating flows with polymer melt materials. Different process designs are considered of pressure‐ and tube‐tooling, complementing earlier studies on individual designs. A novel mass‐balance free‐surface location technique is proposed. The polymeric materials are represented via shear‐thinning, differential viscoelastic constitutive models, taken of exponential Phan‐Thien/Tanner form. Simulations are conducted for these industrial problems through distributed parallel computation, using a semi‐implicit time‐stepping Taylor‐Galerkin/pressure‐correction algorithm. On typical field results and by comparing short‐against full‐die pressure‐tooling solutions, shear‐rates are observed to increase ten fold, while strain rates increase one hundred times. Tube‐tooling shear and extension‐rates are one quarter of those for pressure‐tooling. These findings across design options, have considerable bearing on the appropriateness of choice for the respective process involved. Parallel finite element results are generated on a homogeneous network of Intel‐chip workstations, running PVM (Parallel Vitual Machine) protocol over a Solaris operating system. Parallel timings yield practically ideal linear speed‐up over the set number of processors.

The purpose of this paper is to examine contradictions (specifically tertiary and quaternary contradictions) that can disrupt the flow of work in contemporary systems development methods.

This study uses Activity theory (AT) as a theoretical lens to: examine ISD flow as an interrelated activity system; and identify contradictions. AT is pertinent in the context of this study as rather than view contradictions as a threat to prematurely abandon the use of flow tools and metrics, it shows how contradictions can act as a motor for change and continuity. This study adopts a longitudinal single case study approach including face-to-face interviews with management and software development project teams, as well as direct observations and document analysis.

This study identifies tertiary and quaternary contradictions, and highlights the influence of contradictions on flow-based systems development.

This study provides a set of contradictions for researchers and practitioners. It shows that contradictions can be culturally or politically challenging to confront, and even when resolved, can have intended or unintended consequences.

This paper fulfils an identified need to study ISD flow from the perspective of interrelated activity systems and beyond its initial implementation phase.

As opposed to general literature reviews, by narrowing down the context only around the resources related to Six Sigma tools, this study aims to offer a strong discussion about Six Sigma toolbox which has a vital role in the success of Six Sigma.

Based on a comprehensive literature research, the most used tools; classification of tools; flow of tools with respect to define, measure, analyze, improve and control (DMAIC) steps; tools as critical success factors and reasons of ineffective use of tools are reviewed. To stay focused and not to diverge from the research aim, 60 articles which are suitable to the context and flow of the discussion are selected during the construction of the study.

The study provides a detailed and integrated review of Six Sigma articles about tools. The most used tools are listed from different perspectives and resources, and the role of these tools has been discussed. After a broad review, a more practical and combined classification of Six Sigma tools is proposed. Next, the issue of using which tools during which steps of DMAIC is systematically addressed. Finally, emergence of tools as a critical success factor and the gaps in the literature related to tools of Six Sigma are pointed out.

Addressing important statistics and the facts related to the tools of Six Sigma helps new practitioners in particular to build a strategic filter to select the most proper tools throughout their projects.

This study is unique in investigating only Six Sigma toolbox and providing a literature review on this subject.

Describes a systematic way to design and develop a generic relational model for a tool management system in FMS. Reviews the need for tool database management in FMS and discusses the advantages. Highlights the requirements for a successful tool database and presents a systematic way to design and develop a relational tool database. The developed tool database is implemented by using the ORACLE database management system. Finally, presents four demonstration runs.

Conceptual design is important in that it determines the creativity of products, which is key to the competition of the product market and the function and cost of product are mainly determined in this phase. At the same time it is complex in that it involves the consideration of many different fields in the whole design process. Studying some computer supported cooperative techniques to support effective conceptual design activity is absolutely necessary. This paper presents the models and tools of computer supported cooperative conceptual design (CSCCD) which includes an auto‐resolving model, a human‐human interaction model, automatic cooperation tools and interactive cooperation tools. Experiments have been carried out in the conceptual design of a motorcycle to put the above theories into application.

A major factor to the success of flexible manufacturing systems (FMSs) is their ability to transport work pieces between different workstations. FMS have now become more advanced and material‐handling systems have become progressively more sophisticated, it is not exceptional to have automated steering of tools to workstations as well. Such system design will improve the tool‐handling capability and the system productivity while holding tool cost to a minimum. Tool cost could represent as much as 25 percent of the operating cost. The purpose of this paper is to propose a new colored Petri net (CPN)‐based approach to the design and development of a tool sharing control system that is intended to help use of the proper and minimal number of tools for a manufacturing system.

A new black token timed PN model is first developed, to reduce the complexity of the graphical representation a new CPN model is developed. The new CPN model also allows to find the optimal sequence. The optimal sequence has no effect on the work in process (WIP) but it influences the number of tools used in the system. The main input to the PN model for a manufacturing system is the process plan. Next, all the invariants and total number of possible elementary circuits are determined using the Integrated Net Analyzer (INA) software. Output from the INA software is exported to the Excel spreadsheet. The Excel spreadsheet can be designed to calculate the total number of tokens, processing time, cycle time, etc. of each elementary circuit. Subsequently, the constraints used in Lingo will be created according to critical circuit rules. Finally, linear programming (LP) technique is used to optimize the WIP and tool inventory. Lingo software is used for the LP, the constraints from the Excel sheet will be the input data to the Lingo program, and based on those constraints the Lingo will provide the optimal values for the desired parameters. The output from Lingo will be used to recalculate the cycle time of each elementary circuit in the Excel sheet. The system is then analyzed before and after the implementation of the CPN model.

A new CPN model based on tool‐sharing philosophy for an FMS with N part types and M stations is proposed.

The paper presents a new CPN‐based approach to the design and development of a tool sharing control system, that is, intended to help use of the proper and minimal number of tools for a manufacturing system. The new CPN model also allows to find the optimal sequence. The idea is new and pure and has not been presented before using the methodology adopted in this paper.

The purpose of this paper is to gain insights about the applicability of Lean principles in software industry along with the Lean implementation issues.

Exploratory case studies have been carried out in five software companies. Data were collected by observation and semi-structured interviews with project managers. In this paper, case organizations are categorized as product vs project software development (SD) organization.

It is found that although Lean principles are being adopted in SD projects, application of all Lean principles is not visible. This research reveals that value and flow are more relevant in SD organizations, while value stream, pull and perfection are not conspicuous.

This paper would prove invaluable to lean practitioners and researchers to gain knowledge in lean SD. The paper puts forward the key issues that should be addressed for successful adoption of lean in SD. This study set out to determine the practitioners’ perception of the applicability of lean principles in SD projects. It provides a sound basis for further empirical research on adoption of lean principles in SD organizations.

During years 2014-2016, Veterans Health Administration National Surgery Office conducted a surgical flow improvement initiative (SFII) to assist low-performing surgery programs to improve their operating room efficiency (ORE). The initiative was co-sponsored by VHA National Surgery Office and VHA Office of Systems Redesign and Improvement. The paper aims to discuss this issue.

An SFII algorithm, based on first-time-start (FTS), cancellation rate (CR), lag time (LT) and OR utilization, assigned an ORE performance Level (1-low to 4-high) to each VA Medical Center (VAMC). In total, 15 VAMCs with low-performance surgery programs participated in SFII to assess the current state of their surgical flow processes and used redesign methods to focus on improvement objectives.

At the end of the project, 14 VSAs, 40 RPIWs, 45 “90-day projects” and 73 Just-Do-It’s were completed with 65 percent (158/243) improvement actions and 86 percent sites improving/sustaining all four ORE metrics. There was a statistically significant difference in improvement across the three stages (baseline, improvement, sustain) for FTS (45.6-68.7 percent; F=44.74; p<0.000); CR (16.1-9.5 percent; F=34.46; p<0.000); LT (63.1-36.3 percent; F=92.00; p<0.000); OR utilization (43.4-57.7 percent; F=6.92; p<0.001) and VAMC level (1.7-3.65; F=80.11; p<0.000). The majority developed “fair to excellent” sustainment (91 percent) and spread (82 percent) plans. The projected annual estimated return-on-investment was $27,949,966.

The SFII successfully leveraged a small number of faculty, coaches, and industrial engineers to produce significant improvement in ORE across a large national integrated health care network. This strategy can serve healthcare leaders in managing complex healthcare issues in their facilities.

This study aims to identify the most frequently used tools and techniques within the measure phase of the define, measure, analyze, improve and control (DMAIC) methodology in the Six Sigma Green Belt body of knowledge (BOK) to standardize training curriculum and reduce barriers to Six Sigma adoption.

This study measures the most frequently used tools within the Measure Phase of the Green Belt body of knowledge by surveying Six Sigma professionals from all industries as to how often they use tools specific to the Measure Phase. Professionals rated ten categories of tools based on frequency use as it pertains to a Green Belt level Six Sigma project. Descriptive analysis, t-tests, and ANOVA were performed on the data using Minitab to identify the most frequently used tool categories.

The findings of this study indicate that the most frequently used measure phase tools and techniques within in the Six Sigma Green Belt BOK are process mapping, control charts, descriptive statistics, graphical analysis, collecting and summarizing data, process capability analysis and Six Sigma statistics (defects per unit, defects per million opportunities, etc.). The research findings indicate that several tools that require a higher level of statistical understanding are used less frequently.

The research study solely analyzed the measure phase tools within the Green Belt Six Sigma BOK. Other Six Sigma bodies of knowledge should be evaluated in their entirety.

Six Sigma training has been identified in previous research studies as a barrier to implementation. By identifying the most frequently used tools and determining that those tools are less statistically intensive, companies may be more inclined to adopt Six Sigma. Reducing the tools required to master to lead and carryout Six Sigma projects can also help to reduce the cost and time required for Six Sigma training.

Many studies have identified the lack of a standardized curriculum for Six Sigma and Lean Six Sigma. This research serves to function as a supportive analysis in identifying the most optimal and useful tools to lead successful Six Sigma and process improvement projects and contributes to the journey of establishing a standardized Six Sigma training curriculum.

The application of lean and quality improvement methods is very common in process improvement projects at organisational levels. The purpose of this research is to assess the adoption of Lean Six Sigma™ approaches for addressing a complex process-related issue in the coal industry.

The sticky coal problem was investigated from the perspective of process-related issues. Issues were addressed using a blended Lean value stream of supply chain interfaces and waste minimisation through the Six Sigma™ DMAIC problem-solving approach, taking into consideration cross-organisational processes.

It was found that the tendency to “solve the problem” at the receiving location without communication to the upstream was, and is still, a common practice that led to the main problem of downstream issues. The application of DMAIC Six Sigma™ helped to address the broader problem. The overall operations were improved significantly, showing the reduction of sticky coal/wagon hang-up in the downstream coal handling terminal.

The Lean Six Sigma approaches were adopted using DMAIC across cross-organisational supply chain processes. However, blending Lean and Six Sigma methods needs to be empirically tested across other sectors.

The proposed methodology, using a framework of Lean Six Sigma approaches, could be used to guide practitioners in addressing similar complex and recurring issues in the manufacturing sector.

This research introduces a novel approach to process analysis, selection and contextualised improvement using a combination of Lean Six Sigma™ tools, techniques and methodologies sustained within a supply chain with certified ISO 9001 quality management systems.