Data quality problems in discrete event simulation of manufacturing operations

High-quality input data are a necessity for successful discrete event simulation (DES) applications, and there are available methodologies for data collection in DES projects. However, in contrast to standalone projects, using DES as a daily manufacturing engineering tool requires high-quality production data to be constantly available. In fact, there has been a major shift in the application of DES in manufacturing from production system design to daily operations, accompanied by a stream of research on automation of input data management and interoperability between data sources and simulation models. Unfortunately, this research stream rests on the assumption that the collected data are already of high quality,and there is a lack of in-depth understanding of simulation data quality problems from a practitioners’ perspective.Therefore, a multiple-case study within the automotive industry was used to provide empirical descriptions of simulation data quality problems, data production processes, and relations between these processes and simulation data quality problems. These empirical descriptions are necessary to extend the present knowledge on data quality in DES in a practical real-world manufacturing context, which is a prerequisite for developing practical solutions for solving data quality problems such as limited accessibility, lack of data on minor stoppages, and data sources not being designed for simulation. Further, the empirical and theoretical knowledge gained throughout the study was used to propose a set of practical guidelines that can support manufacturing companies in improving data quality in DES

Auswahl und Bewertung von Verfahren zur Vorbehandlung von Restabfaellen vor der Deponie fuer den Landkreis Northeim

In assessing alternatives of waste management increasing attention is being paid to the environmental impact of individual alternatives as a planning basis. Often the only way of achieving public acceptance of new waste disposal plants is to compare the advantages and disadvantages of as many alternatives as possible in an objective and scientifically well-founded manner. Whereas in the past technical-economic optimisation had priority, today increasing emphasis is placed on process, or product, optimisation with regard to ecological criteria. Ecological optimisation often leads to a revision of opinions, not least because consequential environmental costs have hardly been taken account of in technical-economic optimisation until now. (orig.)Bei der Beurteilung abfallwirtschaftlicher Alternativen wird als Planungsgrundlage zunehmend nach den Umweltauswirkungen gefragt. Eine Akzeptanz fuer Entsorgungsanlagen ist oft nur noch dann zu erzielen, wenn zuvor die Vor-und Nachteile moeglichst vieler Alternativen umfassend, objektiv und wissenschaftlich fundiert gegenuebergestellt werden. Im Gegensatz zur bevorzugten technisch-oekonomischen Optimierung der Vergangenheit tritt heute die Optimierung von Prozessen oder auch Produkten hinsichtlich oekologischer Kriterien mehr und mehr in den Vordergrund. Die oekologische Optimierung wird dabei haeufig zu neuen Bewertungen fuehren, auch weil die Umweltfolgekosten bisher kaum bei der technisch-oekonomischen Optimierung Beruecksichtigung finden. (orig.)Available from TIB Hannover: F94B1634 / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman