1、山东科技大学学士学位论文附录 附录 Assembly line balancing: Which model to use Nils Boysen, MalteFliedner, Armin Scholl Abstract： Assembly lines are flow-line production systems which are of great importance in the industrial production of high quantity standardized commodities and more recently even gained importan
2、ce in low volume production of customized products. Due to high capital requirements when installing or redesigning a line, configuration planning is of great relevance for practitioners. Accordingly, this attracted the attention of research, who tried to support practical configuration planning by
3、suited optimization models. In spite of the great amount of extensions of basic assembly line balancing there remains a gap between requirements of real configuration problems and the status of research. This gap might result from research papers focusing on just a single or only a few practical ext
4、ensions at a time. Real-world assembly systems require a lot of these extensions to be considered simultaneously. This paper structures the vast field of assembly line balancing according to characteristic practical settings and highlights relevant model extensions which are required to reflect real
5、 world problems. By doing so, open research challenges are identified and the practitioner is provided with hints on how to single out suited balancing procedures for his type of assembly system. Keywords:Configuration of assembly lines； Assembly line balancing； Classification 1. Introduction 山东科技大学
6、学士学位论文附录 An assembly line is a flow-oriented production system where the productive units performing the operations, referred to as stations, are aligned in a serial manner. The work pieces visit stations successively as they are moved along the line usually by some kind of transportation system, e.
7、g. a conveyor belt. Originally, assembly lines were developed for a cost efficient mass production of standardized products, designed to exploit a high specialization oflaborand the associated learning effects (Shtub and Dar-El, 1989； Scholl, 1999, p. 2). Since the times of Henry Ford and the famous
8、 model-T however, product requirements and thereby the requirements of production systems have changed dramatically. In order to respond to diversified customer needs, companies have to allow for an individual libation of their products. For example, the German car manufacturer BMW offers a catalogu
9、e of optional features which, theoretically, results in 1032 different models (Meyr, 2004). Multipurpose machines with automated tool swaps allow for a facultative production sequence of varying models at negligible setup times and costs. This makes efficient flow-line systems available for lowvolum
10、e assembly-to-order production (Mather, 1989) and enables modern production strategies like mass customization (Pine, 1993). This in turn ensures that the thorough planning and implementation of assembly systems will remain of high practical relevance in the foreseeable future.Under the term assembl
11、y line balancing (ALB) various optimization models have been introduced and discussed in the literature, which are aimed at supporting the decision maker in configuring efficient assembly systems. Since the first mathematical formalization of ALB by Salve son (1955), academic work mainly focused on
12、the core problem of the configuration, which is the assignment of tasks to stations. Subsequent works however, more and 山东科技大学学士学位论文附录 more attempted to extend the problem by integrating practice relevant constraints, like u-shaped lines, parallel stations or processing alternatives (Becker and Scho
13、ll, 2006； Boysen et al., 2006a). Considering the large variety of regarded extensions, which are referred to as general assembly line balancing (GALB), it is astonishing that there remains a very considerable gap between the academic discussion and practical applications, up to now. Empirical survey
14、s stemming from the 70s (Chase, 1974) and 80s (Schniger and Spingler, 1989) revealed that only a very small percentage of companies were using a mathematical algorithm for configuration planning at that time. The apparent lack of more recent scientific studies on the application of ALB-algorithms in
15、dicates that this gap still exists or even has widened. One reason for this deficit might originate from the fact that research papers often regard single or only just a few extensions of ALB in an isolated manner (Boysen et al., 2006a). Real-world assembly systems require a lot of these extensions
16、in many possible combinations. Thus, flexible ALBprocedures are required, which can deal with a lot of these extensions in a combined manner. Typically, there is a trade-off between flexibility and efficiency of an optimization procedure. Accordingly, by identifying typical combinations of extension
17、s which often arise jointly in real-world assembly systems, procedures can be developed which exactly fit these requirements, while decreasing 2 the required flexibility to a minimum. Moreover, practitioners might be provided with valuable advices on how to use already existing models and procedures for their special assembly system. For that purpose this paper is structured as follows. At first, section 2 summarizes ALB-research by describing ALB in its very basic form (section 2.1) and then classifying further extension from that starting point (section 2.2). Finally, the
