Improving the waiting process at checkouts in stores is an important goal of operations management in the era of time-based competition. The paper presents a method for evaluating the effect of express lines on the waiting process. An optimization model is developed which minimizes the average waiting time in line with respect to the maximum number of items allowed in the express lines. The research is based on a real case of a do-it-yourself superstore, but the methodology applied at the store can be used generally.The optimization model includes sensitivity analyses. Sensitivity analyses show how the optimal value of the limit parameter changes if major parameters of the model change. The results of these analyses help managers make decisions about short and medium-term operations of express lines.The major conclusion of the paper is that the optimal operation of express lines does not improve the average waiting time significantly, but the effect of non-optimal operation can be very unfavorable. Therefore, a successful implementation of express lines requires a thorough analysis of operational issues and a careful consideration of perceptional issues as well.

No abstract

No abstract

This paper presents a research of Markov chain based modeling possibilities of electronic repair processes provided by electronics manufacturing service (EMS)companies IntroductionDuring the last decades, due to the changing economic environment the improvement of business processes to enhance organizational performance has become an important issue resulting in a wide range of management initiatives (TQM, Six Sigma, Lean, BPR, etc.). For this reason, the analysis of processes and the enhancement of process quality has become an important research area in the academic field and a leading managerial issue for the practitioners. Resulting that companies are collecting huge amounts of data, perform complex data and statistical analysis and use sophisticated models; they are competing on analytics (Davenport, 2006;de Vries, 1999).Processes of manufacturing and service companies are described and analyzed with a wide range of tools. The most frequently used techniques include graphical tools (charts and diagrams), matrices, graphical, object-oriented and workfloworiented techniques and generic methodologies as simulation (Aguilar-Savén, 2004). In this paper, Markov chains are applied to analyze business processes. The benefits of the application are demonstrated through a specific business process of industrial electronic repair services.Markov chain based modeling provides process managers with a fast modeling tool. Rapid modeling techniques ensure fast results both for planning and for what-if analysis (Suri and Tomsicek, 1998) which is crucial for companies working in the highly competitive markets of the electronic industry. The requirement of time-based competition and the highly variable processes of Electronic Repair Services (ERPs) (demanding frequent managerial decisions) necessitate quick information for the current operation of any related processes.The proposed Markov chain based modeling results in important information for process improvement and capacity planning. The steps of electronic repair processes are stochastic in respect of their sequence and their length. Consequently, the paths (the sequence of the visited process steps) are also variable for the different items delivered for repair. With the help of the proposed model, the likelihood and the lead time of each possible path and its contribution to the total load of the process can be calculated. This can support the management to identify the

No abstract