On the design and development of scheduling systems

IFIP International Federation for Information Processing, 2004

With the increase of the Internet and virtual communities, interfaces for web applications and automated services are becoming an emergent necessity. In this paper we propose a web interface for enabling access to different manufacturing scheduling methods, which can be remotely available and accessible from a distributed knowledge base. Through this interface users can register and join together as a community and share their scheduling knowledge. Scheduling problems can occur in several different manufacturing environments and the web system searches in the distributed knowledge base for appropriate solving methods. Therefore, through this interface once suitable available methods, for a given problem, are identified, it enables running one or more of them, made accessible by the system. Moreover, new methods can be continuously incorporated in the system's distributed repository, in a user-friendly way, feeding the knowledge base.

Annual Reviews in Control, 2007

A major goal of a supply chain is to ''improve the flow of material between suppliers and customers at the highest speed''. This goal suggests making real time and global management decisions, which involves scheduling. In this paper, we briefly remind the evolution of scheduling activities in industrial environment, describe the current situation and emphasize the problems that call for solutions. #

Lecture Notes in Computer Science, 2002

Production Scheduling is an important function strongly contributing to the competitiveness of industrial and service companies. In this communication we make a contribution for XML based specification of scheduling concepts in order to allow for a standard representation of scheduling problems and related tasks. This information modeling is used in the development of a web based decision support system for the resolution of scheduling problems. An XML-based Knowledge Base System may be useful not only to facilitate the specification of scheduling problems but also in the search for the most suitable available algorithms and methods, which can then be used for finding good solutions to the problems. The existing algorithms, as well as their corresponding implementations, may either be local or remotely available, through the Internet.

IFAC Proceedings Volumes, 1992

Scheduling in a manufacturing environment generally is based on sevezal kinds of information. some of which cannot be handled by a pure numerical approach. In this paper a possible structure fCX' the integration of a nwnerical and a knowledge-based scheduling procedure is presented. The various types of information are described in detail. and the interaction of the components of the system is examined. Keywords. Manufacturing processes. artificial intelligence. heuristic programming. flexible manufacturing. production control. decision theory.

Mathematical and Computer Modelling, 1990

In this paper a knowledge-based scheduling system (KBSS) designed for an automated manufacturing environment is presented. Frames and production rules have been applied to represent declarative and procedural scheduling knowledge. A heuristic algorithm is incorporated into the knowledge-based system. The KBSS allows us to consider basic and alternative process plans. Each process plan specifies manufacturing resources, such as machines, tools, fixtures and material handling carriers, as well as their sequence. The knowledge-based system is illustrated with a numerical example. The heuristic algorithm is the key component of the system. The system has been tested on a number of scheduling problems. Computational experience proves that the solutions generated are of a quality acceptable in industry.

In this paper we describe an ontology for a model of manufacturing scheduling problems to be solved on the web, through several different scheduling methods made available by a web scheduling decision support system. This approach aims enabling to share scheduling knowledge and methods, in a globally distributed context, in order to facilitate solving these problems, either in the industry or in the academic and research context. The proposed ontology is described in terms of basic objects, the scheduling problem attributes, in the form of problems characterization parameters; problem classes or types of scheduling problems and relations among problem classes; and problems instances. Finally, a sample of methods is presented for solving some well known problems arising in the scope of manufacturing scheduling through the web.

AI Magazine, 1986

the constraint knowledge utilized in actual factory environments. This led to the construction of the Intelligent Scheduling and Information System (ISIS), a series of experimental job shop scheduling systems (Fox, Allen, and Strohm 1982; Smith 1984a, 1984b). ISIS-2 was demonstrated in the context of the Westinghouse Turbine Components Plant (WTCP) in Winston-Salem, North Carolina. More recently, we initiated work on a new system called OPIS , which continues to generalize from the ISIS experience and provide greater system flexibility in approaching various scheduling tasks. We feel we have made significant progress in this work, but there are difficult issues that remain to be addressed. This article attempts to coalesce what we have learned thus far and to reflect on the potential of knowledge-based approaches to this difficult problem. Abstract To be useful in practice, a factory production schedule must reflect the influence of a large and conflicting set of requirements, objectives and preferences. Human schedulers are typically overburdened by the complexity of this task, and conventional computer-based scheduling systems consider only a small fraction of the relevant knowledge. This article describes research aimed at providing a framework in which all relevant scheduling knowledge can be given consideration during schedule generation and revision. Factory scheduling is cast as a complex constraint-directed activity, driven by a rich symbolic model of the factory environment in which various influencing factors are formalized as constraints. A variety of constraint-directed inference techniques are defined with respect to this model to provide a basis for intelligently compromising among conflicting concerns. Two Bnowledge-based factory scheduling systems that implement aspects of this approach are described.

Computers & Industrial Engineering, 2005

This work presents the development and implementation of a production scheduling system for an electrical appliance manufacturer. Based on recent advances in optimisation-based scheduling approaches, two different software architectures based on two different scheduling formulations, namely the RTN and the STN, are proposed to integrate information available in the different production units and stages with formal algorithmic tools. Optimization results indicate that significant economic benefits can be achieved (e.g. minimization of total operating costs) while ensuring full customer satisfaction as opposed to normal practices followed in the company relying on human expertise. The work indicates that it is possible to solve real-life manufacturing problems using optimization-based approaches but the integration of information in a timely fashion seems to be a major factor in successfully implementing the system and fully realizing its benefits. q (L.G. Papageorgiou).

This paper deals with the discussion on the use of simulation techniques for work order scheduling on the factory floor level of production and contains a description of the program electronic planning board with simulation elements for Finite Capacity Scheduling. The ability to implement simulation effectively for factory scheduling is dependent upon the availability of shop floor data and the response time for the evaluation process.

This paper describes a web system for supporting manufacturing scheduling in practice. Within this system scheduling concepts like problems and solving methods are modelled through XML. Furthermore, the Internet remote methods' invocation is also based on the XML language and performed using the XML-RPC communication protocol. The architecture and underlying approach of the web system is oriented for solving a large variety of manufacturing scheduling problems based on a continuously updatable distributed knowledge base, which allows a network of peers to provide the scheduling service to users and the dynamic enlargement of the number of methods that can be accessed. This is done in an easy and interactive way.