Scheduling
Because FMS involves a major capital investment, efficent machine utilization is essential. Machines must not stand idle. Consequently, proper scheduling and process planning are crucial. Scheduling for FMS is dynamic, unlike that in job shops where a relatively rigid schedule is followed to perform a set of operations. The scheduling system in FMS specifies the types of operations to be performed on each part and identifies the machines or manufacturing cells where these operations are to take place. Dynamic scheduling is capable of responding to quick changes in product type; hence, it is responsive to real - time decisions.
(Kalpakjian S. , Schmid S.R. , Manufacturing Engineering and Technology, p. 1223)
Groupware
Technological advances have increased the functionality of groupware solutions in the workplace. The role of computer supported collaboration will continue to redefine the strategy and culture of corporations worldwide. Companies are increasingly viewing groupware solutions as a competitive necessity. Achieving success in planning and implementing a groupware installation requires an organization to define communication goals in terms of corporate strategy and full support from all levels of management. Groupware is about people, whether in teams, organizations, or whole enterprises. This article attempts to define the groupware concept and present practical implications of a collaborative implementation in the workplace environment.
(Telematics and Informatics, Volume 15, Issues 1-2, February 1998, p. 85-101)
Production Activity Control
There is a widely perceived gap within the domain of scheduling for manufacturing systems, namely, many of the methods employed by production supervisors are quite different from those developed by researchers. In a sense, this inconsistency highlights the important fact that much scheduling research has failed to win approval where it matters most, namely, within the manufacturing system.
In this article, we argue for a practical approach to scheduling for manufacturing systems, one that we believe can narrow, and possibly bridge, the gap between theory and practice. This approach is based upon a well-defined and modular architecture for scheduling, termed production activity control. This architecture is the foundation of our proposed solution to scheduling, since it provides a coherent blueprint for the synthesis of information technology and scheduling strategies. The result of this synthesis is a design tool for production activity control, which allows for detailed and disciplined experimentation with a range of scheduling strategies in a controlled and simulated environment. Due to the unique modular property of the design tool, these strategies may then be implemented live in a flexible manufacturing facility, hence narrowing the gap between scheduling theory and manufacturing practice. Our overall approach is tested through an appropriate implementation in a modern electronics assembly plant.
(Internal Journal of Flexible Manufacturing Systems, Volume 4, Number 1, p. 79-103)
Soliform Systems
The Soliform creates models from photo-curable resins. The resin developed by Teijin is an acrylic - urethane resin with a viscosity of 40 000 centapoise and a flexural modulus of 52.3 MPa as compared to 9.6 MPa for a grade used to produce conventional prototype models. The properties of the resin and the accuracy of the laser beam are considered more significant.
The Soliform has been used in many areas, such as injection molding (low cost die), vacuum molding, casting and lost wax molding.
Teijin Seiki Co. Ltd., originally founded in 1994, is a diversified industrial components. Its Soliform system is based on the SOMOS (Solid Modeling System) laser curing process developed by Du Pont Imaging Systems. The company acquired exclusive Asian rights to the equipment aspects of this technoloy in 1991 under its Solid Imaging Department, with its first machine shipped in 1992. Since 2001, Teijin Seiki has merged with CMET Inc. under one umbrella. The CMET's company address is Kamata Tsukimura Building, 5-15-8, Kamata, Ohta-cu, Tokyo 144-0052, Japan.
Teijin Seiki Co. Ltd. produces two main series (250 and 500 series) of the Soliform system.
The Soliform system has several technological advantages:
1. Fast and accurate scanning.
2. Good accuracy.
3. Photo resins.
The Soliform system has the following disadvantages:
1. Requires support structures.
2. Requires post - processing.
3. Requires post - curing.
The soliform system contains the following hardware: a SUN-EWS workstation, an argon ion laser, a controller, a scanner to control the laser trace of scanning and a tank which contains the photopolymer resin.
(Chua C. K, Leong K. F and Lim C. S, Rapid Prototyping - Principles and Applications, Second Edition, p. 74-77)
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