Now showing 1 - 4 of 4
  • Publication
    Capacity planning and resource allocation in assembly systems consisting of dedicated and reconfigurable lines
    ( 2014)
    Gyulai, D.
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    Kádár, B.
    ;
    Monostori, L.
    Companies with diverse product portfolio often face capacity planning problems due to the diversity of the products and the fluctuation of the order stream. High volume products can be produced cost-efficiently in dedicated assembly lines, but the assembly of low-volume products in such lines involves high idle times and operation costs. Reconfigurable assembly lines offer reasonable solution for the problem; however, it is still complicated to identify the set of products which are worth to assemble in such a line instead of dedicated ones. In the paper a novel method is introduced that supports the long-term decision to relocate the assembly of a product with decreasing demand from a dedicated to a reconfigurable line, based on the calculated investment and operational costs. In order to handle the complex aspects of the planning problem a new approach is proposed that combines discrete-event simulation and machine learning techniques. The feasibility of the approach is demonstrated through the results of an industrial case study.
  • Publication
    Automatic simulation model generation supported by data stored in low level controllers
    ( 2012)
    Popovics, G.
    ;
    Kardos, C.
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    Pfeiffer, A.
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    Kádár, B.
    ;
    Vén, Z.
    ;
    Monostori, L.
    One of the most widespread techniques to evaluate various aspects of a manufacturing system is discrete-event simulation (DES). However, building a simulation model of a manufacturing system is a difficult task and needs great resource expenditures. Automated data collection and model buildup can drastically reduce the time of the design phase as well as support model reusability. Since most of the manufacturing systems are controlled by low level controllers (e.g., PLCs, CNCs) they store structure and control logic of the system to be modeled by a DES system. The paper introduces an ongoing research of PLC program processing method for automatic simulation model generation of a conveyor system of a leading automotive factory. Results of the validation process and simulation experiments are also described through a case study.
  • Publication
    Execution data connected simulation for production operation planning and control
    ( 2012)
    Kádár, B.
    ;
    Pfeiffer, A.
    ;
    Monostori, L.
    Due to the large number of the resources, the frequent reengineering of manufacturing processes and the often changing product types, the maintenance of the simulation model and the provision of up-to-date input data are almost always difficult. The paper introduces new quantitative analysis method including processing time and batch calculation algorithms applied in the automatic building of discrete-event simulation systems. The simulation model and the mentioned algorithms are both directly interfaced with real execution databases and the overall solution supports the shop-floor managers in making control decisions. The applicability of the elaborated approach is illustrated by the results of experiments relying on real historical data.
  • Publication
    Novel it solutions for increasing transparency in production and in supply chains
    ( 2011)
    Monostori, L.
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    Ilie-Zudor, E.
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    Kádár, B.
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    Karnok, D.
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    Pfeiffer, A.
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    Kemény, Zs.
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    Szathmári, M.
    The paper summarises the main challenges and problems related to transparency in production firms and networks. The transparency problem of production are treated from three aspects, i.e., factory level data gathering tight-coupled with productions simulation; extracting knowledge from large, complex, time-dependent noisy and anomalous process logs; and identity-based tracking and tracing services within and beyond organizational borders. For all these fields of industrial relevance novel approaches and solutions are presented.