A new MRP/GT lot sizing heuristic: A simulation study

This paper studies the lot-sizing problem in Material Requirements Planning/Group Technology (MRP/GT) systems. A GT production cell is designed to produce many families of components. A major setup is required when switching from manufacturing one family of components to another family, and a minor setup is needed when switching from manufacturing a component type to another component type within the same family. Inventory holding cost is incurred if inventory level is positive, and inventory shortage cost is incurred if inventory level is negative, that is, backordering. The objective of the proposed lot-sizing problem is to minimize the sum of major and minor setup costs, holding and shortage costs, and regular production cost, and to meet simultaneously the demand requirements. The proposed problem is modelled into a linear integer program, a heuristic method to solve the problem is proposed, and a simulation experiment conducted to evaluate the performance of the proposed heuristic and some existing heuristics. The computational results show that the proposed heuristic is useful to reduce the total cost significantly over a wide variety of simulated environments.     

Evaluation of heuristics for scheduling in a flowshop: a case study

The problem of finding the best permutation schedule for a flowshop has engaged the attention of researchers for almost four decades. In view of its NP-completeness, the problem is not amenable to the development of efficient optimizing algorithms. A number of heuristics have been proposed, most of which have been evaluated by using randomly generated problems for a single measure of performance. However, real-life problems often have more than one objective. This paper discusses a live flowshop problem that has the twin objectives of minimizing the production run-time as well as the total flowtime of jobs. Five heuristics are evaluated in this study and some interesting findings are reported.     

Setups and effective capacity: the impact of lot sizing techniques in an MRP environment

This study investigates how lot sizing techniques influence the profit performance, inventory level, and order lardiness of an assembly job shop controlled by MRP. Four single-level lot sizing techniques are compared by simulation analysis under two levels of master schedule instability and two levels of end item demand. A second analysis investigates the influence of a multilevel lot sizing technique, the generalized constrained-K (GCK) cost modification, on the four single-level techniques at low demand and low nervousness. The analyses reveal a previously unreported phenomenon. Given the same inventory costs, the single-level lot sizing techniques generate substantially different average batch sizes. The lot sizing techniques maintain the following order of increasing average batch size (and decreasing total setup time):

economic order quantity (EOQ)

period order quantity (POQ)

least total cost (LTC)

Silver-Meal heuristic (SML)

The causes for different average batch sizes among the lot sizing techniques are analysed and explained. Demand lumpiness, inherent in multilevel manufacturing systems controlled by MRP, is found to be a major factor. The number of setups each lot sizing technique generates is the primary determinant of profit performance, inventory level, and order tardiness. EOQ, a fixed order quantity technique, is less sensitive to nervousness than the discrete lot sizing techniques. EOQ_, however, generates the smallest average batch size, and, therefore, the most setups. Since setups consume capacity, EOQ, is more sensitive to higher demand. SML generates the largest average batch sizes, and is, therefore, less sensitive to increased demand. At low demand, the other lot sizing techniques perform better on all criteria. They generate smaller batches and, therefore, shorter actual lead times. The GCK cost modification increases the average batch size generated by each lot sizing technique. GCK improves the profit and customer service level of EOQ the lot sizing technique with the smallest batches. GCK causes the other lot sizing techniques to generate excessively large batches and, therefore, excessively long actual lead times.     

A simulation study of performance of MRP based systems under interaction effects

This paper pertains to a study carried out on a typical Material Requirements Planning (MRP) based system. An integrated MRP based system was developed. This integrated package facilitates studying the effects of variations in Master Production Schedules (MPS), Bill of Materials (BOM) structure, inventory supports, lot sizing, capacity planning, scheduling rules and shop floor conditions. The system behaviour is captured using simulation. The direct and interacting roles of uncertainties, capacity variations, scheduling rules and lot sizing rules on the system performance have been studied in detail. The details of the system, the modules and their capabil-iiies and the analyses of results are presented in this paper.     

Reviewing performance: an analysis of the structure and functions of performance management reviews

This article proposes an analytical framework for conceptualising performance management reviews (PMRs). Drawing on multiple literatures, the article applies Pettigrew et al.'s (Pettigrew, A., Whipp R., and Rosenfield R., 1989. Competitiveness and the management of strategic change processes. In: A. Francis, and P.K.M. Tharakan, eds. The competitiveness of European industry: country policies and company strategies. London: Routledge) framework to develop our understanding of the context, process and content of PMR. The process elements of PMRs are the levers for managerial intervention as they determine the immediate outcome of PMR. They accomplish this task by acting on the content elements, transforming the subject of PMR into specific outcomes. The scope of the intervention, however, is constrained by factors in the organisation's context. This framework sheds light on various functions of PMRs, most notably strategy implementation.     

The Future of HRD Research: A SWOT analysis by five leading scholars in the field

This article presents a review of the 11th International Conference on Human Resource Development Research and Practice across Europe through the lens of global mobility. The conference was held in Pécs, Hungary in June, 2010 and the four authors who participated in the conference present their own narratives as agents of global mobility, examine the theme of global mobility in the various aspects of the conference, and conclude with reflections on the factors that supported the learning environment at the conference.     

Board of directors structure and firm financial performance: A qualitative comparative analysis

Previous research about the effects of board structure and process on the firm financial performance is based on conflicting theoretical perspectives, and empirical results, mostly based on regression analysis, are inconclusive. Building from Complexity Theory and configurational analysis, this study offers clarity to inconclusive previous empirical results about the link among several board features and firm financial performance. From a sample of 295 non-financial firms from Southern Europe for the period 2001–2010, and by using fuzzy set qualitative comparative analysis, findings of this study show that firm financial performance depends on a complex configuration of several board features (board size, board independence, leadership structure and board activity) and several corporate characteristics (firm size, firm leverage and firm age). This paper has implications for academics. Despite different theoretical arguments and inconclusive results of the wide empirical literature addressing the effect of board characteristics on the firm performance, building from Complexity Theory this paper adds to our knowledge because it empirically explores under which circumstances different board features should contribute positively or negatively to firm performance. The results of this study have also implications for policy makers and practitioners by providing some useful hints to the controversial relationship between corporate governance and financial performance. In this sense, general corporate governance recommendations must be rethought.     

Learning from stories of leadership: How reading about personalized and socialized politicians impacts performance on an ethical decision-making simulation

Stories about notable, 20th-century politicians were investigated as a means by which reading stories of leadership influences subsequent ethical decision-making performance. Undergraduates read four short stories in which charismatic politicians exhibited a personalized, socialized, or neutral power orientation, followed by responding to four ethical dilemmas in the marketing domain—a distant transfer task. Results indicated that reading stories featuring personalized protagonists inhibited subsequent ethical decision-making processes. However, intensity of narrative processing, personal identification with the protagonist, and presence or absence of an ethical salience probe moderated these effects. Implications are discussed regarding the use of stories as a tool for ethical development and the importance of managing stories of leadership circulated throughout organizations and society.     

Incorporating quality into data envelopment analysis of nursing home performance: A case study

When using data envelopment analysis (DEA) as a benchmarking technique for nursing homes, it is essential to include measures of the quality of care. We survey applications where quality has been incorporated into DEA models and consider the concerns that arise when the results show that quality measures have been effectively ignored. Three modeling techniques are identified that address these concerns. Each of these techniques requires some input from management as to the proper emphasis to be placed on the quality aspect of performance. We report the results of a case study in which we apply these techniques to a DEA model of nursing home performance. We examine in depth not only the resulting efficiency scores, but also the benchmark sets and the weights given to the input and output measures. We find that two of the techniques are effective in insuring that DEA results discriminate between high and low quality performance.     

Measuring performance of two-stage network structures by DEA: A review and future perspective

Data envelopment analysis (DEA) is a method for measuring the efficiency of peer decision making units (DMUs). An important area of development in recent years has been devoted to applications wherein DMUs represent two-stage or network processes. One particular subset of such processes is those in which all the outputs from the first stage are the only inputs to the second stage. The current paper reviews these models and establishes relations among various approaches. We show that all the existing approaches can be categorized as using either Stackelberg (leader-follower), or cooperative game concepts. Future perspectives and challenges are discussed.     

A novel approach to regression analysis for the classification of quality attributes in the Kano model: an empirical test in the food and beverage industry

Since its introduction in the 1980s, Kano's two-dimensional model has become one of the most popular models with which to evaluate quality, finding a place in a wide range of industries. For decades, various approaches to regression analysis have been applied to explore asymmetric and non-linear relationships in the Kano model. Although a number of authors have questioned the use of these regression methods, there has been a lack of validity testing to evaluate their convergence with the results of the Kano questionnaire in classifying quality attributes. This study proposes a novel approach to regression analysis for the classification of quality attributes, including must-be, one-dimensional, attractive, and indifferent categories, as well as mixed-class distribution. Using popular tools and techniques for the measurement of customer satisfaction, the proposed approach is capable of simplifying the process of collecting data making it far easier to implement than the list of functional and dysfunctional questions initiated by Kano. An empirical study of a food and beverage chain showed that the proposed approach is capable of returning acceptable classification results, compared to the Kano questionnaire. A validity test indicated that the proposed approach significantly outperformed dummy variable regression and the moderated regression. In conclusion, the proposed approach provides a more practical implementation, while maintaining classification power on par with the Kano questionnaire.