Julia Bendul

Autonomous Control of a Shop Floor Based on Bee’s Foraging Behaviour

This paper focuses on the application of a bee-like autonomous control method to a matrix-like shop floor model with setup times. Autonomous control means decentralized coordination of intelligent logistic objects in a dynamically changing environment. By the aid of a continuous flow simulation the system’s performance will be analyzed in regard to the application effect on throughput times and inventory levels.

Synchronization in manufacturing systems: quantification and relation to logistics performance

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 widely assumed that synchronization is beneficial to the logistics performance of manufacturing systems. However, it has been shown that synchronization phenomena can be detrimental to systems in which they emerge. To study if synchronization phenomena also occur in and affect manufacturing systems’ performance, a formal quantification and holistic understanding of the types of synchronization phenomena emerging in manufacturing are needed. This article aims to fill this research gap by developing synchronization measures for manufacturing systems, applying these measures to real-world production feedback data and utilising them to test the assumption about synchronization’s beneficial effect on logistics performance. We identify two distinct synchronization types occurring in manufacturing systems, logistics and physics synchronization, and show that they are negatively correlated. Further, we show that logistics synchronization and due date performance exhibit anti-correlation and thus question the assumption that synchronization leads to higher efficiency in manufacturing systems. This article aids production managers in designing and optimising production systems, and supports further empirical research in production planning and control and production system design.

The Influence of Manufacturing System Characteristics on the Emergence of Logistics Synchronization: A Simulation Study

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 still unclear how manufacturing system characteristics impact synchronization. Thus, the purpose of this paper is to investigate the effect of manufacturing systems’ characteristics on the emergence of logistics synchronization in them. We conduct a discrete-event simulation study to examine the effect of three system characteristics: (1) material flow network architecture, (2) work content variation, and (3) order arrival pattern. Our findings suggest that the material flow network architecture and the work content variation are related to logistics synchronization. Linear manufacturing systems with stable processing times such as flow shops operate at high logistics synchronization levels, while highly connected systems with high variability of processing times such as job shops exhibit lower synchronization levels.

Simultaneous Workload Allocation and Capacity Dimensioning for Distributed Production Control

Abstract Capacity dimensioning in production systems is an important task within strategic and tactical production planning which impacts system cost and performance. Traditionally capacity demand at each worksystem is determined from standard operating processes and estimated production flow rates, accounting for a desired level of utilization or required throughput times. However, for distributed production control systems, the flows across multiple possible production paths are not known a priori. In this contribution, we use methods from algorithmic game-theory and traffic-modeling to predict the flows, and hence capacity demand across worksystems, based on the available production paths and desired output rates, assuming non-cooperative agents with global information. We propose an iterative algorithm that converges simultaneously to a feasible capacity distribution and a flow distribution over multiple paths that satisfies Wardrops first principle. We demonstrate our method on models of real-world production networks.

The elementary flux modes of a manufacturing system: a novel approach to explore the relationship of network structure and function

Elementary flux modes (EFMs) are a concept from Systems Biology, where they serve as an indicator of component relevance in metabolic networks. An elementary flux mode is a functionally relevant, non-decomposable path through a given network. In this paper, we apply elementary flux mode analysis to manufacturing systems, with the aim of using the number of EFMs as a predictor for resource significance in the manufacturing system. For this, we formulate a network representation of a manufacturing process, which allows us to define the manufacturing equivalent of a stoichiometric matrix to draw an analogy between metabolic and manufacturing systems. This, in turn, allows the computation of EFMs, which we conduct in a case-study for a real manufacturing system. We further show that the change of EFMs under resource breakdown is a good indicator of the average order lateness in the manufacturing system. In this way, EFMs provide insight into the relationship of network structure and function in manufacturing.

Does Frugal Innovation Enable Sustainable Development? A Systematic Literature Review

The Sustainable Development Goals set by the United Nations recognize and promote inter- and intra-dependencies between the economic, social and ecological dimensions, emphasize the inclusion of local communities in the development processes and the need for sustainable consumption and production. To achieve these goals, interdisciplinary and collaborative efforts are needed. Frugal innovation emerges as a paradigm challenging traditional innovation pathways which may have the potential to bring together different stakeholders’ efforts to achieve sustainable development goals. This systematic literature review analyzes current research linking the concepts of frugal innovation and sustainable development. The aim is to highlight approaches and conditions in which frugal innovations can drive sustainable development, especially in relation to different types of private sector actors. Based on the content analysis of current studies, we formulate shortcomings of existing research and develop a research agenda with the aim to bring the two research streams closer.Les Objectifs de Développement Durable fixés par les Nations Unies reconnaissent et promeuvent les inter et intra dépendances entre les dimensions économiques, sociales et écologiques, soulignent l’inclusion des communautés locales dans les processus de développement et la nécessité d’une consommation et d’une production durables. Pour atteindre ces objectifs, des efforts interdisciplinaires et collaboratifs sont nécessaires. L’innovation frugale émerge comme un paradigme qui défie les voies d’innovation traditionnelles et qui peut avoir le potentiel de rassembler les efforts des différentes parties prenantes pour atteindre les objectifs de développement durable. Cette revue systématique de la littérature analyse les études actuelles qui relient les concepts d’innovation frugale et de développement durable. L’objectif est de mettre l’accent sur les approches et les conditions dans lesquelles les innovations frugales peuvent stimuler le développement durable, notamment en ce qui concerne les différents types d’acteurs du secteur privé. Sur la base de l’analyse du contenu des études actuelles, nous formulons des lacunes des études existantes et développons un programme de recherche dans le but de rapprocher les deux axes de recherche.

Integration of global manufacturing networks and supply chains: a cross case comparison of six global automotive manufacturers

Striving for new business opportunities automotive original equipment manufacturers established overseas plants in emerging markets and global manufacturing networks evolved. In this regard so-called knocked down supply chains have been the key for the establishment of successful overseas operations. Importing all parts required from the original plants in form of easy to be handled kits secures a high product quality and stable supply despite lacking qualification of local workforce and supplier bases. Over time the overseas plants and global manufacturing networks have matured by increasingly taking over value adding processes and integrating local suppliers. However, the supply chain structure and management have not been adapted accordingly and still comprise high inventory buffers and lead times. There is little research on the integrated design of global manufacturing networks and knocked down supply chains. This research aims to contribute to close this research gap by means of a cross-case study with six globally operating OEMs investigating the fit of knocked down supply chains and global manufacturing networks. On the basis of transaction cost theory, we develop an integrated framework to align global manufacturing networks and knocked down supply chain design that can serve as guideline to open logistics performance and cost potentials.

Influencing factors of synchronization in manufacturing systems

Manufacturing systems exhibit two types of synchronisation phenomena: logistics and physics. Previous research has established synchronisation measures for both types and has shown that they are related to the due date performance. However, there is a lack of knowledge about the factors triggering synchronisation emergence as well as a holistic understanding of synchronisation effects on logistics performance. Thus, this research aims to further explore the relation between synchronisation, its influencing factors and its effect on logistics performance. Based on a profound literature review, we derive first hypotheses on the cause-and-effect-relationships between structural and dynamic properties of a manufacturing system and the emergence of logistics and physics synchronisation as well as logistics performance. By conducting a discrete-event simulation study on diverse manufacturing system types (line, flow shop and job shop production), we are able to test these hypotheses. We conclude that manufacturing network architecture as a structural property as well as processing time variability and system workload as dynamic properties may be exploited for an advanced and synchronisation-oriented manufacturing system design.

The balance of autonomous and centralized control in scheduling problems

The scheduling of processes in a network is a core logistic challenge with a multitude of applications in our complex industrialized world. Often, scheduling decisions are based on incomplete and unreliable information. Here, a simple rule of ’more information, better decisions’ may no longer hold and heuristics balancing global and local information, or centralized and autonomous control, may yield better performance. So far, only anecdotal evidence for the potential benefit of autonomous control in scheduling exists. Here, we explore this hypothesis within a minimal model derived from scheduling principles and the phenomenology of dynamical processes on graphs. In this model, centralized and autonomous control can be represented and quantitatively assessed, performance is well defined and problem complexity can be varied.Our model shows that a balance of centralized and autonomous control can enhance the performance in networks of decision-making entities. The mechanistic insight gained from the model also reveals the limitations of hybrid control setups: We find that communication at a high hierarchy level can give an advantage to centralized control. Counter-intuitively, it arises not from a higher degree of coordination and quicker convergence towards a common solution, but rather from an accelerated sampling of candidate choices leading to a measurable increase in information flow from higher to lower hierarchical levels. Our study allows us to formulate a new view of autonomous control in industrial production and derive a set of suggestions with the potential to enhance performance under realistic conditions of scheduling heuristics of jobs in a production process.

Frugal and Lean Engineering: A Critical Comparison and Implications for Logistics Processes

Frugal innovation gains momentum in literature and practice as the next important management approach transferred from East to West after lean. The two paradigms have launched powerful ideas challenging the traditional Western approaches, with frugal innovation being the most recent. This paper focuses on the application of lean management and frugal innovation in the field of engineering. The principles employed during the design stages are responsible for a high percentage of logistics costs and consequently influence significantly logistics processes. Therefore, we highlight similarities and differences of the two approaches, and show how to combine the underlying principles in order to develop more efficient products with efficient production processes especially for cost-sensitive consumers in both developing and developed countries. The implications of lean and frugal engineering for procurement, production, distribution and disposal logistics are relevant not only for sustainability managers, product or logistics managers concerned with sustainability aspects but also for executives aiming to expand their operations in developing countries.