Stanislav Chankov

• The term ‘synchronization’ in manufacturing refers to the provision of the right components to the subsequent production steps at the right moment in time. It is assumed that synchronization is beneficial to the logistics performance (LP) of manufacturing systems (MS). However, in the field of natural sciences synchronization is seen as the adjustment of rhythms due to interaction and it has been shown that synchronization phenomena can be detrimental to systems in which they emerge. Hence, the aim of this thesis is to investigate how synchronization can be explored to achieve better LP in MS. In a first step, a formal quantification and holistic understanding of the types of synchronization phenomena emerging in MS is established by transferring knowledge from the field of natural sciences. Further, an analysis of real-world production data and a discrete-event simulation study are applied to investigate the cause-and-effect relationships between the MS properties and synchronization emergence as well as LP. Two distinct synchronization types occurring in MS are defined, logistics and physics synchronization, and appropriate quantification measures for each of them are developed. Moreover, both structural and dynamic MS parameters are identified as factors triggering synchronization emergence in MS. Network properties of the material flow network (structural property) as well as processing time variability and workload level (dynamic properties) are found to influence emergence. Furthermore, the investigation of synchronization’s relation to LP shows that it is not straightforward and depends on different factors. Four LP indicators are studied: short throughput times, low WIP levels, high due date performance (DDP) and high capacity utilisation. It is shown that both logistics and physics synchronization phenomena relate positively to LP in most cases. However, depending on the MS and the specific DDP measure, for example, they can also have negative effects.