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While applications of TQM tools and techniques in health care service industry are widely advocated, determination of customer satisfaction and factors of dissatisfaction in the hospitals has become enormously important as the main ingredient of TQM. This paper aims at determining the elements of customer satisfaction, by collecting information through survey, using both written questionnaire and interview, and then statistically determining correlation between factors and elements of dissatisfaction. The study is performed at the Muang Petch Thonburi Private Hospital, located in Petchaburi province of Thailand. The aim of the management is to gather information on customer satisfaction levels and factors of dissatisfaction that need to be addressed and subsequently eliminated in the near future.

This paper presents a new generic Petri net (PN) model for design and performance evaluation of a flexible assembly system (FAS) and disassembly system (DAS) with dual kanban. The architectural design of the model is derived from a generic bill of materials (BOMs) in the FAS, a reverse BOM in the DAS and the process plan in the case of flexible manufacturing system (FMS). Integration of FMS, FAS and DAS by developing a new generic PN model with the pull system is introduced. Analysis and performance evaluation of the new model based on invariant analysis and linear programming are also introduced. The method will be illustrated by a small case study.

In the real world many companies combine the operations of manufacturing, assembly and disassembly. Thus, the integration of just‐in‐time FMS, FAS, and flexible disassembly system (DAS) models poses an interesting problem. The purpose of this paper is to provide major emphasis on a new simulation model for design and performance evaluation of a flexible assembly and disassembly system with dual Kanban under a stochastic system. This paper also primarily investigates the effect of varying the number of kanban cards, mean inter‐arrival time of demand and locations of the bottlenecks on the performance integration of JIT flexible manufacturing, assembly and disassembly systems.

Simulation is carried out in ARENA and data is analyzed using multivariate analysis of variance (MANOVA). This paper investigates the effect of varying number of kanban cards, mean inter‐arrival time of demand, and locations of the bottlenecks on the performance integration of JIT flexible manufacturing, assembly and disassembly systems. The performance measures that are simultaneously considered are the fill rate, work in process, and mean cycle time. This paper emphasizes that understanding the interactions between the variables and their effects on system performance is of utmost importance for managers in improving performance processes.

In manufacturing practice, there are many industrial units that represent the mixture of the referred three models. This paper presents a new simulation model for design and performance evaluation of a flexible assembly and disassembly system with dual kanban. The simulation results are statistically compared with MANOVA. MANOVA is used to perform the test with multiple objective functions, e.g. with the average production cycle time, percentage average fill rate, and work‐in‐process. The conclusion to be drawn is that minimized WIP can be obtained by higher percentage average fill rate, lower WIP, small average part cycles times, and increasing in kanban cards while simultaneously retaining full customer satisfaction.

The researcher presents the newly developed kanban system into the production system of JIT flexible manufacturing, assembly and disassembly system with simulation technique. Furthermore, by assigning time factors to the models, several performance measures can be easily computed. Then, the researcher tests the effect of the number of kanban card on integration of JIT flexible manufacturing, assembly and disassembly systems using a simulation approach, the simulation model is developed using the ARENA simulation package. The results are applied to a small case study. For a single product under the integration of JIT flexible manufacturing, assembly and disassembly systems, as the number of kanban cards increase, the fill rate along with work in process and the mean cycle time increases as well.

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.