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This paper presents a systematic approach to characterize integration challenges when implementing mission engineering and discusses some specific techniques to address these issues. With the introduction of mission engineering in the DOD science and technology lexicon, integration assumes a new dimension beyond the system product level. First, the authors offer a more precise definition of integration that focuses on incorporating a new technology or military capability into an existing organization's infrastructure. Using a collection of system integration literature and a set of examples, the authors define major problem areas regarding integration. Analyses of these issues present opportunities to identify specific methods to avoid or mitigate them. The resultant process is a foundation for mission engineering practitioners to plan successful integration of a new system. Acceptance of these procedures in the mission engineering community may lead to inclusion as standard practices in the DOD Mission Engineering Guide. [ABSTRACT FROM AUTHOR]

This paper involves the design and construction of the intake manifold system of the FSAE car including the air shroud, air filter, throttle body, restrictor plenum, fuel injectors, fuel rail and runners. To ensure the quality, the proposed system is designed based on the FSAE rules. The design process of the intake manifold system will consist of the usual engineering processes including computer modelling, Finite Element Analysis and finally Computational Fluid Dynamics testing in order to determine the validity of the model and to tune the design in order to obtain the optimum performance out of the intake manifold system as a whole. [ABSTRACT FROM AUTHOR]

The objective of the article is to present the linking of simulation and planning software. The paper begins with a review of recent literature as well as description of the problem under investigation. Following from practical requirements, five decision-making rules were implemented to the production process. In the final part, the overall results to ensure time and economic efficiency of the production process are presented. The obtained results show that the best option is to apply the rule during which the first part to be machined is the one that first enters the production process to ensure minimum production time, maximum machine load and limit machine costs. By application of this rule, the total production time accounts for 524 seconds at the total cost of 7914.60 €. The overall benefits of the research are being described in details in the final part of the article. [ABSTRACT FROM AUTHOR]

Coordination is essential for improving supply chain performance, and one of the most critical factors in achieving the coordination of a supply chain is the integrated research of production and distribution. In this paper, a novel two-stage hybrid solution methodology is proposed. In the first stage, products are processed on the serial machines of multiple manufacturers located in two industrial parks. A fuzzy multi-objective scheduling optimization is performed using a modified non-dominated sorting genetic algorithm II (NSGA-II). The result obtained in the first stage is used in the second stage to optimize the distribution scheduling problem using a modified genetic annealing algorithm (GAA). Finally, simulation results verify both the feasibility and efficiency of the proposed solution methodology. [ABSTRACT FROM AUTHOR]

The paper presents research work concerning difficult-to-cut materials turning and chipbreakers reliability in local operating features. Inconel 718 alloy was used as a sample material and two different chipbreakers were tested. The aim of the research was to check the efficiency of chipbreakers in the area of applications recommended by tool manufacturers. As a result, the algorithm for cutting data selection and correction which combines experiments and simulation processes concerning chip breakage effectiveness was built. To estimate chip forms in tests, the visual system equipped with a high-speed camera was used. The cutting forces measuring system provided information for verification of simulation results. The simulation based on the FEM was applied to estimate chip groove filling. Distributions of temperature and stresses on the tool rake face in the function of distance from the cutting edge were calculated. The paper gives recommendations for cutting data correction to achieve acceptable chip forms. [ABSTRACT FROM AUTHOR]

Resin infusion (RI) process has been widely used for manufacturing composite parts. The variation of preform thickness brings great difficulty to the three-dimensional simulation of the filling stage. To accurately simulate the preform thickness change and resin flow during resin infusion, precise preform compaction models and dynamically changing geometry models need to be adopted. At present, resin flow is usually considered as two-dimensional and simple compaction models are employed to simplify the simulation, which degrades the prediction accuracy seriously. In this paper, general equations to describe the resin flow in the changing thickness cavity are developed, and the viscoelastic model is adopted which can fully express the dynamic characteristics of the preform compaction. To avoid solving the coupled resin flow/preform deformation equations directly, the volume of fluid method and the dynamic mesh model are employed to implement the tracking of the flow front and updating of cavity geometry model. The resin storage and release induced by porosity variations are adjusted by a master-slave element method to ensure mass conservation. Two simulation examples are carried out to demonstrate the capability of the above approach. The applicability of the approach on arbitrary complex domains and sequential injection strategy is also verified. [ABSTRACT FROM AUTHOR]

This paper describes the application of computer aided design (CAD) in teaching advanced design methodologies to fourth-year undergraduate students majoring in mechanical engineering. This involves modern enhancements in teaching strategies for subjects such as designfor- X (DFx) and failure mode effect analysis (FMEA) concepts, which are traditionally categorised as advanced design methodologies. The main subsets of DFx including design-for-assembly (DFA), design-for-disassembly (DFD), design-for-manufacturing (DFM), design-for-environment (DFE) and design-for-recyclability (DFR) were covered by studying various engineering and consumer products. The unit was designed as a combination of practical hands-on workshop-based classes along with a software-based evaluation of different products. In addition to CAD, finite element modelling techniques were utilised to enhance the students' understanding of design faults and failures. The inquiry into teaching practice and design of this fourth-year unit was carried out during past two years and it revealed some interesting outcomes from our teaching practice in terms of students' learning experiences. Finally, the paper discusses some critical factors in the context of teaching advanced design methodologies to the undergraduates in mechanical engineering and even manufacturing engineering. [ABSTRACT FROM AUTHOR]

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]

Interactive assembly based on virtual reality offers users an opportunity to interact with a virtual prototyping rather than a physical one and to validate assembly performance of products in a realistic way. Such evaluations could be available very early in the product development process ahead of any physical prototyping. The reduction or elimination of physical prototyping needed for assembly performance validation can substantially shorten the product development cycle and reduce development cost. Although virtual reality technology provides users an intuitive and immersive 3D interactive interface, it tends to be inaccurate because humans have difficulty in performing precise positioning tasks. Therefore, it is necessary to implement effective motion manipulation for assembly operations so that users can perform precise positioning efficiently in virtual assembly systems. This paper presents a constrained behavior management approach that realizes assembly relationship recognition, constraint solution and constrained motion for interactive assembly in a virtual environment. A constrained behavior manager (CBM) has been developed and applied in virtual assembly systems. Test cases confirm that constrained behavior manipulation proposed in this paper not only increases the efficiency of assembly relationship recognition, but also facilitates assembly interaction in a virtual environment. [ABSTRACT FROM AUTHOR]

Discrete event simulation (DES) has been widely applied to modelling and simulation of computer and engineering systems and is an active field of research that has now evolved from 2D to 3D discrete event simulation. This paper attempts to address several key issues in a successful implementation of DES models based on our own and the previous experiences of others. It describes the common basis, which forms the core for the application of modelling and simulation methodologies that are available to support manufacturing systems analysis, design and performance evaluation. Through a comprehensive literature survey, this paper summarises and compares the most widely used optimisation techniques for simulation of manufacturing systems; an overview of the recent and popular simulation languages and packages available for the modelling and simulation community and the classification of their utility for modelling and simulation of manufacturing systems is also given. Finally, this paper summarises and reports the latest development in the most exciting world wide web (www)-based simulation techniques that represent a future that may completely change the nature and future exploitation of modelling and simulation technology in industry. [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]

During powder based additive manufacturing processes, a component is realized layer upon layer by the selective melting of powder layers with a laser or an electron beam. The density of the consolidated material, the minimal spatial resolution as well as the surface roughness of the resulting components are complex functions of the material and process parameters. So far, the interplay between these parameters is only partially understood.In this paper, the successive assembling in layers is investigated with a recently described 2D-lattice Boltzmann model, which considers individual powder particles. This numerical approach makes several physical phenomena accessible, which cannot be described in a standard continuum picture, e.g. the interplay between capillary effects, wetting conditions and the local stochastic powder configuration. In addition, the model takes into account the influence of the surface topology of the previous consolidated layer on the subsequent powder layer.The influence of the beam power, beam velocity and layer thickness on the formation and quality of simple walls is investigated. The simulation results are compared with experimental findings during selective electron beam melting. The comparison shows that our model, although 2D, is able to predict the main characteristics of the experimental observations. In addition, the numerical simulation elucidates the fundamental mechanisms responsible for the phenomena that are observed during selective beam melting. [ABSTRACT FROM AUTHOR]

As in the foundation and principles for complex process science and engineering, a major problem is the lack of formal specification language to treat the dynamics of modeling complex processes with its simulations, emulations and enactments. This paper defines a formal specification language which allows integrating the complex thinking with software engineering principles for guiding the characterization of minimum requirements to design technology within living complex processes. There is a lack of research in the literature referring to the model process structural complexity. Such a model complex process can be directed toward acquiring good maintainability attributes according to the principles of complex process science and engineering. In this work a Value Based Business Process Management Network Model (VBPMN) is developed to acquire directly from the target complex process codes the knowledge hidden among and within composite and elementary complex processes. [ABSTRACT FROM AUTHOR]

Layered manufacturing has emerged as a highly versatile process to produce complex parts compared with conventional manufacturing processes, which are either too costly to implement or just downright not possible. However, this relatively new manufacturing process is characterized by a few outstanding issues that have kept the process from being widely applied. One such issue is the reduced part accuracy caused by the primitive method of generating the layer contours. Current practice generates the layer contours by simply intersecting a set of parallel planes through the computer model of the design part. The volumetric geometry of each layer is then constructed by extruding the layer contour by the layer thickness in the part building direction. This practice often leads to distorted part geometry due to the unidirectional bias of the extruded layers. This paper proposes a novel scheme to correct the systematic part distortion of layered manufactured parts resulting from the improperly generated layer contours. A new layer contour generation method utilizing the sectional projected data of a point cloud representation of the part surface is introduced. The systematic part distortion is reduced by extruding the outer boundary of the projected point data into the layer volumetric geometry. The boundary contour construction algorithm is able to adapt to changing density of the point set in order to keep the captured level of detail consistent. Specifically devised case studies were carried out to validate the proposed method. [ABSTRACT FROM AUTHOR]

This paper presents an integrated computer simulation, goal programming, and design of experiment (DOE) algorithm to solve the jobshop scheduling problem with multiple objectives. The proposed algorithm is applied to an actual textile dyeing, printing, and finishing workshop for minimization of tardiness and makespan. The simulation model enables managers to find schedule of jobs on machines given a defined combination of decision parameters which provide the smallest completion time of jobs. We then utilize DOE for determining the decision parameters to estimate the effect of both qualitative and qualitative factors through metamodeling. A goal programming model is used to find the optimum values of decision variables subject to a set of technical and managerial constraints. The proposed algorithm concentrates on two main managerial objectives simultaneously whereas previous studies are able to consider a single criterion. Finally, distinctive features of the proposed approach are compared with previous studies and models. [ABSTRACT FROM AUTHOR]

This paper proposes a technique for estimating steady-state quantiles from discrete-event simulation models, with particular attention paid to cycle time quantiles of manufacturing systems. The technique is based on the Cornish-Fisher expansion, justified through an extensive empirical study, and is supported with mathematical analysis. It is shown that the technique provides precise and accurate estimates for the most commonly estimated quantiles with minimal data storage and low computational requirements. [ABSTRACT FROM AUTHOR]

The development process of manufactured products is very similar to the natural process of evolution in living beings. The evolution of living beings is caused by variation of their chromosomes. Since the evolution of living beings is very slow, gene engineering has been developed to reform consciously the chromosomes for living beings to accentuate good characteristics. In a similar manner, manufactured products also possess genetic and evolutional information, their analogous or virtual chromosome can be deduced, and their innovation can also be actively implemented using gene-engineering techniques. This paper applies gene-engineering techniques to develop such an innovative design method, which is different from the conventional design methods and innovates products via artificial differentiation of virtual chromosomes of manufactured products. It provides a logically structured process, that can reduce blindness to innovation and can even further clone a product with the aid of advanced virtual reality technology. [ABSTRACT FROM AUTHOR]

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]

The ultimate goal of future manufacturing is to design, test, and manufacture parts in a virtual environment before they are sent to the shop floor While Part I of this paper presents the modeling of process simulation in a virtual environment, this second part presents computationally efficient algorithms for optimal selection of depth of cut, width of cut, speed, and feed while considering process constraints and variation of the part geometry along the tool path. The objective function is selected as the material removal rate (MRR), and optimization of milling processes is based on user defined constraints, such as maximum tool deflection, torque/power demand, and chatter stability. The MRR is maximized by optimal selection of cutting speed, feed rate, depth, and width of cut. Two alternative optimization strategies are presented. Preprocess optimization provides allowable depth and width of cut during part programming at the computer aided manufacturing stage using chatter constraint, whereas the postprocess optimization tunes only feed rate and spindle speed of an existing part program to maximize productivity without violating torque, power and tool deflection limits. Optimized feed rates are filtered by considering machine tool axis limitations, and the algorithms are tested in machining a helicopter gear box cover. [ABSTRACT FROM AUTHOR]

Recently, manufacturing systems have become large scale and complex. The social scientific approach is one of the promising methods to facilitate effective operation for the resource allocation problems in manufacturing systems, since the approach takes an analogy of social systems which are optimal and robust in nature. In this paper, the authors first propose a modeling methodology for an oligopolistic virtual market, and develop an oligopolistic virtual market as an experimental model. Then they clarify several important characteristics of the oligopolistic virtual market by computer simulation experiments, and try to apply the proposed method into a utility computing operational problem to validate its effectiveness into resource allocation problems. © 2008 Wiley Periodicals, Inc. Electr Eng Jpn, 164(1): 77–85, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20628 [ABSTRACT FROM AUTHOR]

To meet the dynamically changing market requirements, production enterprises are collaborating in the form of production chains to share life cycle engineering data/knowledge as well as to improve production efficiency and product quality. This paper proposes a model-based control mechanism and intelligent control layer, which is used to control the operation of chained production enterprises. The control mechanism is achieved by defining control levels as mapped to production chain topology using the concept of operation isolation area. Production constraints and control rules are defined as attached to structure elements. The proposed control layer is used to decide the suitable operation of the selected production chain, in view of process constraints and operating conditions. A case study of a generic production chain with recycling is used to show the proposed control mechanism. [ABSTRACT FROM AUTHOR]

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]

Assembly line balancing (ALB) aims at distributing those work required to assemble a product in mass or series production among a set of workstations in an assembly line. Heuristics approaches, in corporation with computer simulation, have demonstrated a number of advantages in practice. Recognizing the importance of interactions between production planners and the scheduling system, this paper discusses the design and implementation of a Web-based ALB advisor for scheduling hard disk drive assembly involving multiple criteria. With the assistance of such an ALB advisor, production engineers, who may have difficulties in understanding those sophisticated ALB heuristics, can remotely present and specify their particular ALB problems. Based on the user input, the advisor will compose a schedule based on various heuristic algorithms embedded in its library. The schedule can be manipulated directly via a graphical user interface. The advisor also generates simulation models for the user-specified ALB problems and presents the user with performance evaluation of the suggested ALB solutions. [ABSTRACT FROM AUTHOR]

This paper proposes a method by which material in- homogeneity may be taken into account in a reliability calculation. The method employs Monte-Carlo simulation; and introduces a material strength index, and a standard deviation of material strength to model the variation in the strength of a component throughout its volume. The method is compared to conventional load-strength interference theory. The results are identical for the case of homogeneous material, but reliability is shown to reduce for the same load as the component volume increases. The case of a tensile bar is used to explore the variation of reliability with component volume. [ABSTRACT FROM AUTHOR]

A geometric tolerance specification includes specifying the tolerance types and values for nominal geometry parts. In current computer-aided tolerancing practices, designers have to specify manually both tolerance types and values in a CAD system, usually starting out from single components. The paper presents a framework and computer implementation that provides automated methods for the specification of geometric tolerance types. Based on the ISO/TC 213 geometric product specification, a new concept of a variational geometric constraints network is presented. The generation and application of the network to specify geometric tolerance types is studied. An example is analysed to show the scheme to be effective, and the model for a tolerance specification, including the types and values specification, is presented. [ABSTRACT FROM AUTHOR]

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]

An introduction is presented in which the editors discuss papers presented during Multiscale Multiphase Process Engineering (MMPE) 2014 including the topics numerical simulations of particle movement, mass transfer and surface wetting, and new measurement methods for non-spherical particles.

The past two decades have seen a rapid increase of interest in computer simulation in many fields of industrial engineering (IE) research and practice. Once regarded as, perhaps, too computationally intensive for wide application, simulation use has been fueled by advances in computing capabilities and decrease in cost. Likewise, computer software for simulation has become a substantial industry, with dramatic improvements in capability, speed and usability. In fact, simulation has become an essential component of many projects, not only aiding the design of systems but also improving their ongoing operation. Although hardware and software developments have made simulation far more accessible, there remain challenges to the effective use of simulation and its ultimate impact. Accordingly, intense interest has developed in researching many subjects surrounding the use of simulation, particularly in IE contexts. The purpose of this special issue is to highlight simulation research, as well as, illustrate how practice has both benefited from motivated research. The editors received excellent response to their call for papers in terms of numbers and strength. All papers were thoroughly refereed.