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1 – 10 of over 28000Paul L. Goethals and Byung Rae Cho
The selection of the optimal process target for a manufacturing process is critically important as it directly affects the defect rate, rejection and rework costs, and the loss to…
Abstract
Purpose
The selection of the optimal process target for a manufacturing process is critically important as it directly affects the defect rate, rejection and rework costs, and the loss to customers. A recent review of process target literature suggests that future work should incorporate models using multiple quality characteristics. Thus, the purpose of this paper is to create a more flexible and realistic approach to solving the multi‐response process target problem.
Design/methodology/approach
A design of experiments methodology is proposed to provide estimates of process parameters and a nonlinear constrained optimization scheme is employed to identify optimal settings.
Findings
The approximation of cost savings undoubtedly has a higher degree of accuracy than in the case where the engineer assumes values for the process parameters. Furthermore, greater flexibility is obtained in finding solutions that support both the manufacturer and the customer.
Research limitations/implications
This methodology relies on controlled experimentation and the replication of observations made on multiple nominal‐the‐best quality characteristics. Future research may include examining the effects of using smaller‐the‐better or larger‐the‐better type characteristics.
Originality/value
Unlike traditional attempts at solving the process target problem where the process mean, variance, and covariance between characteristics are assumed known in advance, this paper uses an approach that removes these assumptions, thereby providing a more practical depiction of the overall system. Furthermore, this methodology broadens the scope of process target problem research by seeking the simultaneous optimization of process parameters and considering a loss in quality attributed to deviation from a target value.
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Abbas Al-Refaie, Mays Haddadin and Alaa Qabaja
The purpose of this paper is to propose an approach to determine the optimal parameters and tolerances in concurrent product and process design in the early design stages…
Abstract
Purpose
The purpose of this paper is to propose an approach to determine the optimal parameters and tolerances in concurrent product and process design in the early design stages utilizing fuzzy goal programming. A wheelchair design is provided for illustration.
Design/methodology/approach
The product design is developed on the basis of both customer and functionality requirements. The critical product components are then determined. The design and analysis of experiments are performed by using simulation, and then the probability distributions are adopted to determine the values of desired responses under each combination of critical product parameters and tolerances. Regression nonlinear models are then developed and inserted as constraints in the complete optimization model. Preferences on product specifications and process settings, as well as process capability index ranges, are also set as model constraints. The combined objective functions are finally formulated to minimize the sum of positive and negative deviations from desired targets and maximize process capability. The optimization model is applied to determine the optimal wheelchair design.
Findings
The results showed that the proposed approach is effective in determining the optimal values of the design parameters and tolerances of the critical components of the wheelchair with their related process means and standard deviations that enhance desired multiple quality responses under uncertainty.
Practical implications
This work provides a general methodology that can be applied for concurrent optimization of product design and process design in a wide range of business applications. Moreover, the methodology is beneficial when uncertainty exists in quality responses and the parameters and tolerances of product design and its critical processes.
Originality/value
The fuzziness is rarely considered in research and development stage. This research considers membership functions for parameters and tolerances of a product and its related processes rather than crisp values. Moreover, presented optimization model considers multiple objective functions, sum of deviations and process capability. Finally, the indirect quality responses are calculated from the best-fit probability distributions rather than assuming a normal distribution.
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The purpose of this paper is to integrate the decisions regarding optimal process mean and the parameters of a sampling plan.
Abstract
Purpose
The purpose of this paper is to integrate the decisions regarding optimal process mean and the parameters of a sampling plan.
Design/methodology/approach
A model is developed to determine these parameters. The model maximizes producer expected profit, while protecting the consumer through a constraint on the probability of accepting lots with low incoming quality. The model is presented for two cases. The first one is for non‐destructive testing and the other for destructive testing. An example is presented to demonstrate that the utility of the model and sensitivity analysis on key parameters of the model has been conducted.
Findings
The findings indicated that the optimal parameters for the process and the sampling plan are significantly different from when determined separately. The sensitivity analysis showed that the process parameters are very sensitive to changes in the process variance, moderately sensitive to the limit on incoming quality, and insensitive to the consumer risk and inspection cost.
Practical implications
The models developed offer an alternative approach for quality managers to address setting process targets, taking into consideration a sampling plan.
Originality/value
The originality of the paper is in the integration of two elements of quality that are usually treated separately in the literature.
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The purpose of this paper is to characterize mechanical properties (tensile, compressive and flexural) for the three-dimensional printing (3DP) process, using various common…
Abstract
Purpose
The purpose of this paper is to characterize mechanical properties (tensile, compressive and flexural) for the three-dimensional printing (3DP) process, using various common recommended infiltrate materials and post-processing conditions.
Design/methodology/approach
A literature review is conducted to assess the information available related to the mechanical properties, as well as the experimental methodologies which have been used when investigating the 3D printing process characteristics. Test samples are designed, and a methodology to measure infiltrate depths is presented. A full factorial experiment is conducted to collect the tensile, compressive and bending forces for a set of infiltrates and build orientations. The impact of the infiltrate type and depth with respect to the observed strength characteristics is evaluated.
Findings
For most brittle materials, the ultimate compression strength is much larger than the ultimate tensile strength, which is shown in this work. Unique stress–strain curves are generated from the infiltrate and build orientation conditions; however, the compressive strength trends are more consistent in behavior compared to the tensile and flexural results. This comprehensive study shows that infiltrates can significantly improve the mechanical characteristics, but performance degradation can also occur, which occurred with the Epsom salts infiltrates.
Research limitations/implications
More experimental research needs to be performed to develop predictive models for design and fabrication optimization. The material-infiltrate performance characteristics vary per build orientation; hence, experimental testing should be performed on intermediate angles, and a double angle experiment set should also be conducted. By conducting multiple test scenarios, it is now understood that this base material-infiltrate combination does not react similar to other materials, and any performance characteristics cannot be easily predicted from just one study.
Practical implications
These results provide a foundation for a process design and post-processing configuration database, and downstream design and optimization models. This research illustrates that there is no “best” solution when considering material costs, processing options, safety issues and strength considerations. This research also shows that specific testing is required for new machine–material–infiltrate combinations to calibrate a performance model.
Originality/value
There is limited published data with respect to the strength characteristics that can be achieved using the 3DP process. No published data with respect to stress–strain curves are available. This research presents tensile, compressive and flexural strength and strain behaviors for a wide variety of infiltrates, and post-processing conditions. A simple, unique process is presented to measure infiltrate depths. The observed behaviors are non-linear and unpredictable.
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Educational management's main task is to achieve learning quality outcomes in acquiring knowledge, scientific skills and social values. This study aims to provide a background on…
Abstract
Purpose
Educational management's main task is to achieve learning quality outcomes in acquiring knowledge, scientific skills and social values. This study aims to provide a background on Egyptian thought development in educational management from 1990 to 2020.
Design/methodology/approach
In this study, we used the descriptive method to collect and interpret data. This method aims to describe an object of phenomena after data collection, analyze it, identify the conditions and relationships between variables and monitor the challenges arising from Egypt's educational system's problems.
Findings
The results showed the following: (1) the trend toward decentralization of educational management is not fulfill during that period and (2) the district and directorate administration continued to receive administrative instructions from the managerial ladder's highest authorities. The Ministry of Education was in control of policy decision-making processes and administrative and financial responsibilities. Many decisions and laws hinder decentralization, such as centralizing examinations, curricula and teachers' recruitment and transfer.
Originality/value
The challenges of developing educational management are related to the shortage of modern management methods in administrative leadership, organizational behavior and decision-making, such as human relations and decentralized administration. Also, the insufficient material resources, managerial competencies and educational, intellectual stagnation among many leaders and administrators.
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Hemantha S. B. Herath, Wayne G. Bremser and Jacob G. Birnberg
Empirical evidence indicates that effective management of resources to implement strategy in a balanced scorecard (BSC) system is essential. We present a mathematical model for…
Abstract
Purpose
Empirical evidence indicates that effective management of resources to implement strategy in a balanced scorecard (BSC) system is essential. We present a mathematical model for allocating limited resources in the BSC strategy implementation process.
Methodology/approach
The proposed facilitated negotiation model provides a systematic approach to prioritizing strategic initiatives in the design and implementation of a BSC.
Findings
Our joint decision model prioritizes strategic initiatives and concurrently calculates the optimal (or approximately optimal) set of BSC targets and weights, given multiyear resource restrictions.
Practical Implications
The model assumes full, open, and truthful exchange of information between the parties; an assumption that may exclude many organizations.
Social Implications
We address an important gap in the BSC literature on how organizations can effectively link strategy to the potential constraint of resource budgets.
Originality/value
Quantitative models are being used in practice for allocating resources, but we are not aware of their use by organizations for allocating resources in a BSC application.
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Marc Wouters, Susana Morales, Sven Grollmuss and Michael Scheer
The paper provides an overview of research published in the innovation and operations management (IOM) literature on 15 methods for cost management in new product development, and…
Abstract
Purpose
The paper provides an overview of research published in the innovation and operations management (IOM) literature on 15 methods for cost management in new product development, and it provides a comparison to an earlier review of the management accounting (MA) literature (Wouters & Morales, 2014).
Methodology/approach
This structured literature search covers papers published in 23 journals in IOM in the period 1990–2014.
Findings
The search yielded a sample of 208 unique papers with 275 results (one paper could refer to multiple cost management methods). The top 3 methods are modular design, component commonality, and product platforms, with 115 results (42%) together. In the MA literature, these three methods accounted for 29%, but target costing was the most researched cost management method by far (26%). Simulation is the most frequently used research method in the IOM literature, whereas this was averagely used in the MA literature; qualitative studies were the most frequently used research method in the MA literature, whereas this was averagely used in the IOM literature. We found a lot of papers presenting practical approaches or decision models as a further development of a particular cost management method, which is a clear difference from the MA literature.
Research limitations/implications
This review focused on the same cost management methods, and future research could also consider other cost management methods which are likely to be more important in the IOM literature compared to the MA literature. Future research could also investigate innovative cost management practices in more detail through longitudinal case studies.
Originality/value
This review of research on methods for cost management published outside the MA literature provides an overview for MA researchers. It highlights key differences between both literatures in their research of the same cost management methods.
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M.A. Rahim and Khaled S. Al‐Sultan
Recently, there has been a lot of interest in the economics of quality control. Many researchers have considered the problem of determining the optimal target mean for a process…
Abstract
Recently, there has been a lot of interest in the economics of quality control. Many researchers have considered the problem of determining the optimal target mean for a process, but almost all of them have assumed that the process variance is fixed and known in advance. The problem of simultaneously determining the optimal target mean and target variance for a process is considered. This might result in a reduction in variability and in the total cost of the production process. A reduction in variability upholds the modern concept of Taguchi’s loss function, which states that any deviation from the target value incurs economic loss, even when the quality characteristic lies within the specification limits. Taguchi’s loss function is incorporated to extend this study further to jointly determine the optimal target mean and variance.
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Hemantha S.B. Herath, Wayne G. Bremser and Jacob G. Birnberg
The balanced scorecard (BSC) allows firms to place importance on both financial and nonfinancial performance measures in four perspectives for developing and implementing…
Abstract
The balanced scorecard (BSC) allows firms to place importance on both financial and nonfinancial performance measures in four perspectives for developing and implementing corporate strategy and performance evaluation. The BSC literature however provides minimal insight on how to set targets, how to weigh measures when evaluating managers and the firm, and how to resolve conflicts that arise in the BSC process. Researchers have attempted to fill these gaps using two contending approaches. In particular, Datar et al. (2001) uses an agency model to select the optimal set of weights and more recently Herath et al. (2009) develop a mathematical programming–based collaborative decision model to find the optimal (or approximately optimal) set of target and weights considering inputs from two parties. In this article, we apply the Herath et al. (2009) model to a detailed BSC example. We demonstrate how the collaborative BSC model can be implemented in Microsoft Excel by practitioners to minimize BSC conflicts. Finally, we discuss how the model facilitates alignment and a culture of open reporting (information sharing) around the BSC that is necessary for its effective implementation.
Sorour Farokhi and Emad Roghanian
The purpose of this paper is to propose a quantitative methodology for setting targets in the framework of Balanced Scorecard (BSC) in order to achieve vision and goals.
Abstract
Purpose
The purpose of this paper is to propose a quantitative methodology for setting targets in the framework of Balanced Scorecard (BSC) in order to achieve vision and goals.
Design/methodology/approach
Response Surface Methodology is proposed to find the significant relationships that should be included in the strategy map and the optimal values of performance measures are assessed by using the desirability function-based approach of RSM. The proposed method was created by reviewing the existing literature, modeling the problem, and applying it in an oil company. In fact, RSM is used to execute the design matrix, analyze the collected data, extract models, analyze the results, and optimize the procedures that generate multiple responses.
Findings
By applying this methodological design, a clearer picture of the relationships between strategic objectives is obtained and the influence of strategic objectives on one another is determined. Afterward, optimal values for performance measures are determined.
Research limitations/implications
This paper proposes a framework for constructing a strategy map and setting quantitative targets to translate the goals and strategies into corresponding performance measures and targets. Also, this paper presents a case study to demonstrate the applicability and effectiveness of the proposed approach. However, RSM-based techniques require a greater amount of data to generate more accurate results. Although the advent of the Information Age has forced organizations’ decision makers to provide sufficient information and data for business analysis, the data requirements of RSM-based techniques are met.
Practical implications
In practice, the process of setting targets for performance measures can be challenging in terms of reaching a consensus between managers and decision makers. The findings of this paper can offer a new approach for performance evaluation based on the BSC which allows the organization’s decision makers to reach a more accurate picture of the relationship model between organization goals and those objectives within the BSC. It also demonstrates how decision makers can be guided in the process of defining performance target values in the BSC method.
Originality/value
Reviewing the literature on setting quantitative targets within the framework of the BSC showed no prior study in which RSM is used. This approach has two main contributions: the associations among strategic objectives are investigated and obtained in an effective way which analytically identifies the direction and degree of the relations among the performance measures. Considering the performance evaluation structure based on the BSC, quantitative targets have been determined to help in achieving the long-term goals of the organization. The application of the proposed method in a company showed that the contributions of this research are not only theoretical, but practical as well.
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