A survey of simulation techniques in commerce and defence

Despite the developments in Modelling and Simulation (M&S) tools and techniques over the past years, there has been a gap in the M&S research and practice in healthcare on developing a toolkit to assist the modellers and simulation practitioners with selecting an appropriate set of techniques. This study is a preliminary step towards this goal. This paper presents some results from a systematic literature survey on applications of M&S in the commerce and defence domains that could inspire some improvements in the healthcare. Interim results show that in the commercial sector Discrete-Event Simulation (DES) has been the most widely used technique with System Dynamics (SD) in second place. However in the defence sector, SD has gained relatively more attention. SD has been found quite useful for qualitative and soft factors analysis. From both the surveys it becomes clear that there is a growing trend towards using hybrid M&S approaches

Multi Agent Systems in Logistics: A Literature and State-of-the-art Review

Based on a literature survey, we aim to answer our main question: “How should we plan and execute logistics in supply chains that aim to meet today’s requirements, and how can we support such planning and execution using IT?†Today’s requirements in supply chains include inter-organizational collaboration and more responsive and tailored supply to meet specific demand. Enterprise systems fall short in meeting these requirements The focus of planning and execution systems should move towards an inter-enterprise and event-driven mode. Inter-organizational systems may support planning going from supporting information exchange and henceforth enable synchronized planning within the organizations towards the capability to do network planning based on available information throughout the network. We provide a framework for planning systems, constituting a rich landscape of possible configurations, where the centralized and fully decentralized approaches are two extremes. We define and discuss agent based systems and in particular multi agent systems (MAS). We emphasize the issue of the role of MAS coordination architectures, and then explain that transportation is, next to production, an important domain in which MAS can and actually are applied. However, implementation is not widespread and some implementation issues are explored. In this manner, we conclude that planning problems in transportation have characteristics that comply with the specific capabilities of agent systems. In particular, these systems are capable to deal with inter-organizational and event-driven planning settings, hence meeting today’s requirements in supply chain planning and execution.supply chain;MAS;multi agent systems

New Shop Floor Control Approaches for Virtual Enterprises

The virtual enterprise paradigm seems a fit response to face market instability and the volatile nature of business opportunities increasing enterprise’s interest in similar forms of networked organisations. The dynamic environment of a virtual enterprise requires that partners in the consortium own reconfigurable shop floors. This paper presents new approaches to shop floor control that meet the requirements of the new industrial paradigms and argues on work re-organization at shop floor level.virtual enterprise; networked organisations

Approaches of production planning and control under Industry 4.0: A literature review

Purpose: Industry 4.0 technologies significantly impact how production is planned, scheduled, and controlled. Literature provides different classifications of the tasks and functions of production planning and control (PPC) like the German Aachen PPC model. This research aims to identify and classify current Industry 4.0 approaches for planning and controlling production processes and to reveal researched and unexplored areas of the model. It extends a reduced version that has been published previously in Procedia Computer Science (Herrmann, Tackenberg, Padoano & Gamber, 2021) by presenting and discussing its results in more detail. Design/methodology/approach: In an exploratory literature review, we review and classify 48 publications on a full-text basis with the Aachen PPC model’s tasks and functions. Two cluster analyses reveal researched and unexplored tasks and functions of the Aachen PPC model. Findings: We propose a cyber-physical PPC architecture, which incorporates current Industry 4.0 technologies, current optimization methods, optimization objectives, and disturbances relevant for realizing a PPC system in a smart factory. Current approaches mainly focus on production control using real-time information from the shop floor, part of in-house PPC. We discuss the different layers of the cyber-physical PPC architecture and propose future research directions for the unexplored tasks and functions of the Aachen PPC model. Research limitations/implications: Limitations are the strong dependence of results on search terms used and the subjective eligibility assessment and assignment of publications to the Aachen PPC model. The selection of search terms and the texts’ interpretation is based on an individual’s assessment. The revelation of unexplored tasks and functions of the Aachen PPC model might have a different outcome if the search term combination is parameterized differently. Originality/value: Using the Aachen PPC model, which holistically models PPC, the findings give comprehensive insights into the current advances of tools, methods, and challenges relevant to planning and controlling production processes under Industry 4.0Peer Reviewe

Multi-controller Based Software-Defined Networking: A Survey

Software-Defined Networking (SDN) is a novel network paradigm that enables flexible management for networks. As the network size increases, the single centralized controller cannot meet the increasing demand for flow processing. Thus, the promising solution for SDN with large-scale networks is the multi-controller. In this paper, we present a compressive survey for multi-controller research in SDN. First, we introduce the overview of multi-controller, including the origin of multi-controller and its challenges. Then, we classify multi-controller research into four aspects (scalability, consistency, reliability, load balancing) depending on the process of implementing the multi-controller. Finally, we propose some relevant research issues to deal with in the future and conclude the multi-controller research

Land as a Renewable Resource: Integrating Climate, Energy, and Profitability Goals using an Agent-Based NetLogo Model

The objectives of this study center over the course of the beef production life cycle as a management strategy to optimize the financial and natural resource endowment on farms at the county level based on the data available. Although the application is to West Virginia, implications can be derived for other areas with similar resource endowments. The beef farms located in adjacent locations within a county are identified as suppliers of inputs to the farm of interest (or contracting farm) in order to provide the basic foundation for agglomeration economies.;Both an intertemporal component and a spatial component are involved since clustering systems are enhanced when key players are interconnected over space. This is accomplished by using an optimal control framework as the basis of a NetLogo agent-based model (ABM) that explicitly includes a spatial component. This model is intended to provide a foundation for developing agglomeration economies in which other locations are able to supply resources to given locations - or to serve as input markets - by taking advantage of the spatially integrated nature of the agriculture industry. The spatial component provides the basis for regional economic development through clustering among the agricultural and other sectors since they might share locally produced inputs/outputs in the supply chain, thereby enhancing both scope economies and agglomeration economies. Thus, the integration of environmentally friendly technologies that enhance diversified products for the area such as renewable energy as well as digested manure along with high quality beef products and carbon offsets would create new markets which expand market channels and spur economic development, of interest to policy makers at all levels. As a result, farmers would be able not only to produce essential inputs for their own farms but, given appropriate incentives, would also supply them to adjacent farms boosting the local economy. Furthermore, a comparison with conventional, confined animal feeding operations (CAFOs), is briefly provided for perspective as well as the basis for environmental improvement through PBB techniques. Our intention is to replicate a diversified PBB industry and its interaction with surrounding communities in order to identify the optimized paths of the farmer and society in an intertemporal setting. The design of policy instruments is based on the results from the ABM wherein maximizing farm-level profitability that is able to bring benefits to society in which clustering among locations contributes in intensifying the benefits from the adoption of sustainable best management practices (BMPs). Thus, the explicit recognition and use of multifunctional land attributes enables us to address bio-fuel production and climate-related issues such as carbon offsets as well as to expand adoption of sustainable BMPs across space and time. In order to determine policy instruments, we ran our ABM with the absence of carbon prices and cost-share programs as well as different carbon prices and cost-share percentages under different clustering systems along a planning horizon of 15 years. We also compared the profitability between a diversified entrepreneur with a specialized business as an approach to identify the financial motivation to establish our proposed business concept. Results indicate that in order to observe environmental and social benefits as well as economic development in Appalachia through the introduction of a diversified PBB industry, a combination of cost-share policies and carbon prices must be considered. Our results imply that for an average grass-fed beef enterprise with 93 acres of pastureland (as is typical of Appalachia) as the primary resource surrounded by nearby cow/calf farms within an approximate 20 mile radius, will need to rely on a minimum of {dollar}13 per ton CO2e reduced along with a cost share program willing to share the risk of no less than half of the capital investment associated with an anaerobic digester within a clustering system of up to two participants to successfully diversify its business bringing environmental and economic development to the region. Alternatively, a policy combination of 50 percent cost share with a {dollar}26 carbon price not only will enhance environmental improvement but also profitability under unexpected as well as certain weather conditions. We also found that more renewable energy can be generated when more farms join a regional cluster, implying a synergistic effect through clustering. We estimate results under both deterministic and stochastic situations. The latter relate primarily to weather uncertainty and animal death loss, since those are the variables for which data is available. (Abstract shortened by UMI.)