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Abstract: In the highly competitive market, cooperative multi-agent transaction and negotiation mechanism have become an important research topic. This paper uses multi-agent technology to construct a multi-section flexible manufacturing system (FMS) model, and utilizes simulation to build a manufacturing environment based on JADE framework for multi-agent to combine with dispatching rules, such as shortest imminent processing time (SIPT), first come first serve (FCFS) earliest due date (EDD), and Buffer Sequence. This paper finds that using multi-agent technique for multi-section FMS model can enhance the production efficiency in practice. Meanwhile, in this study, multi-agent systems combined with dynamic dispatching can be used to identify the best dispatching rules combination for achieving largest throughput, and thus it can provide the reference for production scheduling in advance. [Copyright &y& Elsevier]

This paper compiles selected predictive analytical and numerical tools which can be used to model and understand the mechanisms of importance at different stages during and immediately after extrusion-based 3D printing of cementitious materials. The proposed toolbox covers different aspects of the process including mixing, material transportation, layer deposition, mechanical behavior of the fresh printed structure, and its early curing. Specifically, the paper provides basic analytical methods that should be helpful for an initial, first-order analysis of a given printing process. These methods deliver, in turn, a first estimation of some material requirements and process parameters. Limitations of these analytical methods are also discussed. Furthermore, the paper presents a review of advanced numerical tools that can be used to simulate the steps in the printing process accurately. It is shown that these tools can serve to describe complex behaviors, help in designing process parameters, or optimizing the rheological response, even though further developments are still needed to capture fully the attendant physical mechanisms. [ABSTRACT FROM AUTHOR]

Clamping errors in workpiece positioning decrease the outcome of machine tools. To avoid rejects, which occur due to failures in the clamping, a sensory clamping system is being investigated at the Institute of Production Engineering and Machine Tools (IFW). The aim is to provide hydraulic clamping elements with sensory capabilities to enable condition and process monitoring of the clamping system inside the harsh environment of a machine tool. Firstly, this paper gives a general survey of the targeted application and the concept to achieve a sensory clamping system for the industrial use in series production. Then it focuses on the integration of strain gauges into the exemplary chosen hydraulic swing clamp. Hereby, it shows the qualification of strain gauges for the estimation of different objectives, like hydraulic pressure, piston position, and external loads. Therefore, methods for the identification of suitable positions for the strain gauge integration into the clamping element are being discussed on the basis of experimental results and simulations. Furthermore, a method to achieve higher sensor sensitivity by 71% to the detriment of the compliance by 1.3% is presented. [ABSTRACT FROM AUTHOR]

Abstract: Petri Nets have come to play an important role in modeling and analysis. In day manufacturing systems are very complex and need in depth analysis before implementing them. Various models have been proposed for the evaluation of these systems. Stochastic Petri nets are an emerging modeling tool for performance evaluation of manufacturing systems. Petri net based models are executable thus the performance measures can be obtained by direct simulation of the net the AGV system considered is for a job shop consisting of machines with an input and output buffer. The simulation module computes the probability p(i,j) of having j tokens in place p(i). The aim is to find out the minimum number of parts required to keep some level of throughput and to ensure allow completion time for the batch size considered. Deadlock is to be used clearing of machines or AGVs or buffers, and then restart of the system from an initial condition that is known to produce deadlock-free operation under nominal production conditions. The loss of production and the labor cost is reorganizing the system by proper design. In this paper the authors have developed a model for a manufacturing system with deadlock and analyzed it to generate the reachability tree using Petri net system. In this problem the system consists AGV, Machines and L/D station. [Copyright &y& Elsevier]

Abstract: Within the TINA (Transient Integrated Network Analysis) research project and in partnership with Total, IFP is developing a new generation of simulation tool for flow assurance studies. This integrated simulation software will be able to perform multiphase simulations from the wellbore to the surface facilities. The purpose of this paper is to define, in a CAPE-OPEN compliant environment, a numerical and computational strategy for solving pressure-driven steady-state simulation problems, i.e. pure simulation and design problems, in the specific context of hydrocarbon production and transport from the wellbore to the surface facilities. [Copyright &y& Elsevier]

Abstract: The dynamics of product life cycle for a family of products presents a complex manufacturing scenario. As the demand pattern is ever changing, the manufacturing system also has to be reconfigured in order to align its production capability with demand. This paper addresses the complex relationship between the product life cycle for a family of products and the manufacturing systems performance optimization via reconfiguration. The optimization strategy consists of three main steps: simulation of the original configuration, optimisation of the reconfigured system and finally product portfolio optimisation. Full discussions on results are given in terms of system sensitivity and optimization efficiency and the deployment of reconfiguration. [Copyright &y& Elsevier]

Abstract: The paper summarises the main challenges and problems related to customised mass production. In the elaborated solution the reference for real-time production control is generated by a novel scheduling system. Detection of changes and disturbances emerging during the daily production is based on the integration of information coming from the process, quality and production monitoring subsystems. All the information forms the basis of rescheduling policies. In the proposed framework both the more traditional discrete event simulation (in different settings) and the agent-based approach plays key role. The effectiveness of the proposed solutions is shown by experimental results on industrial data. [Copyright &y& Elsevier]

Abstract: In a manufacturing system, we need to capture collaborative processes among its components in order to clearly define supporting functions of a system. However, pervasive process modeling techniques, including IDEF3, Petri Nets, and UML, are not sufficient for modeling collaborative processes. Therefore, we have developed a novel modeling method referred to as collaborative process modeling (CPM) to describe collaborative processes. CPM models can be transformed into marked graph models so that we can use the analysis power of Petri Nets. In this paper, we first briefly discuss these process modeling techniques. Then, we illustrate the CPM method and transformation rules with illustrative examples. CPM allows us to develop collaborative process models, understand and facilitate the realization of collaboration, and verify models before moving onto development. [Copyright &y& Elsevier]

In order to successfully develop a new tube hydroforming (THF) process, a system approach is recommended. Problems and improvements in each area of the THF technology and their interactions should be considered. In the product and process design phases, in order to reduce the cost of physical prototyping, virtual prototyping, i.e. computer simulation using finite element analysis (FEA) plays a major role. Both input data and strategies used in FEA must be carefully selected, if an accurate and relatively fast response is required. The first part of this paper briefly reviews the technological areas, critical for obtaining reliable input FEA data, i.e. quality and material properties of incoming tubes and die–workpiece interface issues. The second part describes some of the FEA strategies developed and currently used at the ERC/NSM for effective process design. [Copyright &y& Elsevier]

Simulation by a software model, is one of the most frequently used techniques for the analysis and design of manufacturing systems. In the software engineering research area, the object-oriented approach has fully demonstrated to be an effective technique with respect to the design and implementation phases of complex software projects. Even if object-oriented programming has proven to be a powerful technique, a systematic design method should also be used in order to implement reliable software, in particular in the development of simulation models. This paper presents a new procedure to develop flexible manufacturing system (FMS) simulation models, based on the UML analysis/design tools and on the ARENA® simulation language. The two main features of the proposed procedure are the definition of a systematic conceptual procedure to design FMS simulation models and of a set of rules for the conceptual model translation in a simulation language. The goal is to improve the software development efficiency through a rule-based approach and to add some of the fundamental object-oriented features to the ARENA® simulation environment. [Copyright &y& Elsevier]