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The article discusses the problem of total waste separation in the frame of a computer simulation design of these systems. The aim of the article is to employ computer simulation, modelling and logistics for the needs of total separation of waste and its recycling into the form of raw materials and re-usable resources in practice. The results of the computer simulation show that by using total separation and waste recycling in the specifically analysed region, it is possible to produce approximately 7700 tons of recycled paper, 2400 tons of multilevel packages, 8000 tons of glass, 3000 tons of old textiles, 3500 tons of iron, approximately 1500 tons of non-ferrous metals, approximately 2700 tons of wooden pallets, approximately 1200 tons of rubber granulate, to process approximately 800 tons of dangerous waste, 2400 tons of electro waste, 2100 tons of gravel, 840 tons of sand and to liquidate approximately 3200 tons of non-recyclable waste during the whole year. [ABSTRACT FROM AUTHOR]

Achieving dynamic simulation of industrial safety management is of great significance for industrial safety management. To cover the shortage of existing simulation methods in being used in industrial safety management, especially their deficiency in integrating the theories, methods and technology achievements within multi-disciplinary and multi-field, an approach to dynamic simulation of industrial safety management is proposed in this paper based on knowledge unit and with the fusional computation of data, knowledge and model as the core of the approach. In this approach, the internal relations between data, knowledge and model are achieved by knowledge unit. And through the reasoning of knowledge unit network, the fusional computation of data, knowledge and model within various disciplines and fields is realized. Then the simulation of industrial safety management is further achieved. At the end of the paper, an example is analysed to prove the effectiveness of the proposed approach. [ABSTRACT FROM AUTHOR]

The use of simulation in a project management can illustrate visual display of the project objective and the process virtually but realistically. This paper investigates the valid benefits of using simulation technique for a Mining and Iron Production Factory (MIPF) project. It is believed by the author that mining activity is particularly subject to more risks than other business activities because of its uncertainty, complexity and high cost. One of the first things to consider before starting mining projects is the risk factor. Some project risks can be reduced by visualizing and understanding the process before the actual initiation process. The paper illustrated the advantages of using computer aided simulation for an optimization project of a MIPF in a real life case study. [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]

This paper attempts to overcome the defects of bottleneck recognition and scheduling optimization in open production line. For this purpose, the author analysed the impact mechanism of external disturbances and system configuration changes on the production line, and put forward a multibottleneck identification model for production line through computer simulation. Then, the proposed model was applied to optimize the scheduling of open production line. Specifically, the bottlenecks of production line were identified based on hierarchical clustering and multi-attribute decision-making, aiming to overcome the small candidate set and low accuracy of traditional bottleneck identification algorithms. The measured results show that the proposed algorithm has clear primary and secondary logics; the number of main bottleneck clusters decreased with the increase in the order; the number of machines in the main bottleneck cluster changed nonlinearly. The traditional genetic algorithm (GA) was improved in three aspects: the local optimum trap was avoided by enhancing population diversity; the iteration speed was accelerated with the introduction of adaptive crossover operator and genetic operator; without sacrificing the computing speed, the convergence quality was guaranteed through the addition of multivariate competition algorithm. The research findings provide new insights into the efficient operation of production line. [ABSTRACT FROM AUTHOR]

At present, AGV systems are an important part of numerous companies and their internal logistics systems. They are used to efficiently secure different types of transport processes in order to minimize operating costs. However, their reliable operation requires adequate setting and maintenance. Computer simulation is probably the most suitable option from a wide range of engineering methods with which to meet these requirements. This paper describes the development of a simulation model in the Tecnomatix Plant Simulation program to identify critical points of failure within a specific delivery process on the basis of a Milk Run system. Based on the results obtained, an appropriate solution was determined with which to make the whole process function more efficiently and reliably. [ABSTRACT FROM AUTHOR]

The paper presents a specific application of fractals, which are used for a heat pipe cooling device design. A heat pipe is a simple device that can quickly transfer heat from one point to another. This new device was developed for some years in Politehnica University of Bucharest by a group of multi-disciplinary group researchers lead by this paper authors. To investigate the cooling characteristics it has been used three Peano fractals structures: Hilbert, Hutchinson and Koch curve. The design was validated through basic experimental tests. [ABSTRACT FROM AUTHOR]

This paper explains the reasons for selecting the right project to conduct business in various organisations. It presents several methods for evaluating and selecting projects. A special focus is on Analytical Hierarchy Process (AHP) method that is becoming increasingly important tool in different decision-making situations. We have used this method in project management and developed a project evaluation and selecting process. We have also developed a simple application in MS Excel that helps with calculating projects' total priority grade. This tool helps us with simulating project importance based on changes in perception of the criteria. [ABSTRACT FROM AUTHOR]

The paper presents a new method for the acquirement of new knowledge and skills by means of Role-Play Simulation. The substance of the method rests in team experimentation with a model of Quality Management System prepared in advance. Experimentation may be applied to any of organizational structure, strategy, quality policy and quality objectives, selection of the quality management system model, managerial roles, and all quality management processes. One of the main assets of such experiments is "the overcoming of resistance to change". The final solution to the Quality Management Role-Play Simulation can be achieved in a consensus among role-play participants on the basis of value analysis of submitted partial solutions. The paper is intended for all professionals who are concerned with educational theory, human behaviour theory and/or new methodologies in the field of Quality Management System. The paper is written as a part of work on the research project KEGA 3/6411/08 Transformation of an existing study programme Production Quality Management into a university bilingual study program. [ABSTRACT FROM AUTHOR]

Coining as metal forming technology is known for its technological complexity and phenomenological problems. Development of 3D scanners and FE codes, have enabled the simulation of coining using verse and obverse medal geometry. This includes simulation of details up to the scale where flow related phenomenon is observable. Modification of coin/medal geometry can be made during any of the phases in die production. This paper is trying to establish a connection between commercial FE code and 3D digitalization in the field of minting. This results in potentially significant savings in tool production, allowing geometry modification, at any moment including the moment of artist creation of coin's obverse and reverse. Paper demonstrates the simulation of coining using digitized medal geometry, within the appropriate FE numerical code that enables the completion of virtual coining. [ABSTRACT FROM AUTHOR]

Simulations are widely used in manufacturing system design, production planning and decision making. The aim of this paper is to present the possibility of using Monte Carlo simulations in the production plan optimizing and in the project risk management. Optimization is accomplished through two different approaches which principles and results are mutually compared. According to the first approach, production optimization is performed via a deterministic model using the Generalized Reduced Gradient algorithm. The second approach is based on the stochastic model. The optimized production plan is submitted to risk analysis. Two approaches are demonstrated in order to reduce the rate of risk. The first way is modifying the production plan to increase the forecast reliability; the second approach is limiting the uncertainty of key variables. The detailed methodology enables implementing presented approaches in solving various optimization tasks. [ABSTRACT FROM AUTHOR]

Currently, robotic manufacturing cells entail complex decisions concerning sequencing issues due to uncertainty which arises in different parameters such as time to failure, time to repair and cycle times that can be effectively supported by computer simulation models. The paper is focused on part sequencing of a two-machine robotic cell in a flow shop which produces different parts. The process is supported by a single gripper robot to load/unload products and also in displacement within the system. This study considers machine failures and repair such that S2 cycle time and total production cost should be minimized. In this study, simulation facilitated input part sequence and also data envelopment analysis method is applied to trace the optimum sequence for satisfying the objective functions. Results through some numerical examples showed some simulation advantages specially to model many uncertainties and what if analysis. [ABSTRACT FROM AUTHOR]

Oil jet lubrication performance directly influences the operation, reliability and fatigue life of meshing gears working under high-speed and heavy-load conditions in the main reducer of rotorcraft. An oil-air two-phase mixture flow numerical simulation model for jet lubrication on the surface of a pair of meshing gears was established by the computational fluid dynamics (CFD) simulation code ANSYS/FLUENT. The effects of the spin flow caused by a high-speed rotating gear pair on the jet flow trajectory deviation were considered in the numerical simulation. The oil volume and oil pressure distribution characteristics of the meshing area were obtained and compared according to different nozzle position layouts, and the optimal nozzle position layout was determined to obtain a maximum oil volume and oil pressure. A gear-jet-lubrication experimental system was built in which the meshing surface temperatures were measured by an infrared thermometer; meanwhile, the jet flow trajectories were photographed by a high-speed camera. The experimental and numerical simulation results were mutually validated and proved the proposed optimal design scheme for the nozzle position layout. [ABSTRACT FROM AUTHOR]

The aim of this article is to create a simulation model of specific production system in Plant Simulation environment. The main production program that we monitor in this article is focused on the production of tapered roller bearings. Types of produced products are wide; therefore we focus attention on a material flow of one particular dimensional type of bearing. This article is divided into five parts. In the first part there is a theoretical overview of utilization of the system module Plant Simulation. The second part is focused on product that will be used for simulation process, concretely tapered roller bearing 32303A. Third part deals with analysis of simulated system model in Plant Simulation. Fourth section is oriented on proposal of monitored production system optimization in Plant Simulation and final fifth part is about benefits evaluation of the proposed solution. [ABSTRACT FROM AUTHOR]

In the paper we will present a multipolar manufacturing network simulation using a new approach in discrete material flow management. We validate this aproach using a case study of three partners network acting in a virtual enterprise architecture, analyzed in order to optimize the manufacturing design. Two of them represent product suppliers, and the third represents the enterprise where the assembling will take place, after which the final product will result. In order to evaluate the architecture of the system, we used simulation models of the material flow for the three FMS, using the Witness software. The purpose of the simulation is to introduce our new methodology for multipolar distributed simulation of the material flow in the manufacturing networks in order to optimise the activity between partners and to increase the profit. [ABSTRACT FROM AUTHOR]

This paper presents a detailed development process of discrete event simulation model for a single disk drive. Model development process was conducted in several subsequent phases, and each phase introduced a bit more details, until satisfactory results were achieved. Discussed model is customized for workload imposed by the requirements of the ALICE transient storage system, or more precisely, sequential storing and reading of large data files. With this limitation, simulated throughput differed from the measured one about 0.98 % and 0.8 % for storage and reading, respectively. [ABSTRACT FROM AUTHOR]

The work described in this article consists of the development of a simulation model in an Arena environment, based on a real case, and is aimed at a very specific class of production lines, with a four closed-loop network configuration. The purpose of the use of an Arena simulation environment was that of enabling the production engineer to evaluate the performance of the automobile assembly line, through the variation of different parameters, thus contributing to an improved specification, characterisation and definition of the most efficient control system. In this paper we analyze the influence of the speed of the intermediate buffers formed by conveyors in assembly line performance, which has still not been researched in specialist literature. In order to obtain the functions that describe the behaviour of the assembly system, the design of an experiments technique was used. [ABSTRACT FROM AUTHOR]

The aim of the paper is to present the system for multi-criteria evaluation of energy crops for biogas production. Firstly, the deterministic simulation system consists of deterministic production simulation models was build. Simulation model results were further evaluated using a qualitative multi-attribute modelling methodology DEX (supported by the software tool DEX-i). The analysis showed that by using current model the most relevant alternative used for energy crop for biogas production is maize. The maize results in the best DEX-i multicriteria evaluation appropriate. The best alternative for maize is sorghum with multicriteria evaluation less appropriate. [ABSTRACT FROM AUTHOR]

In Finite Element Analysis of the Roll Forming (RF) process of automotive component, there are two methods for numerical simulation. The first one is general analysis, and the second is a specific analysis. The general approach is a deeper investigation but takes a long time for simulation, while the specific approach uses many assumptions for RF, takes less computer time and can analyze many special processes quickly. This paper investigates many RF processes of automotive components by using both methods, in order to identify differences between them as well as build the foundation for using the combination of different methods in analyzing and designing RF process. A realistic application in analyzing and designing is developed and shows the good efficiency in comparison with the previous procedure. [ABSTRACT FROM AUTHOR]

This paper summarizes the optimization process for deflectors designed to lower the water level and ceiling overflow in the S-shaped outflow channel of HPP Vinodol. Parameterized designs of deflectors were optimized using a genetic algorithm that evaluated each setup by running 2D CFD simulations. Optimal designs were chosen by considering total pressure loss and flow uniformity. The resulting best case design set provided a solid basis for simulations using 3D fluid flow numerical models of the channel. Two variants of 3D deflector designs were simulated and a two phase VoF model was used to simulate the free surface with and without deflectors. Both 2D and 3D simulation results show improvements in channel flow and a significantly lower water level justifies further development of deflector design for3D optimization and a future prototype test. [ABSTRACT FROM AUTHOR]

A systematic procedure of experiments, performing simulation in conjunction with work measurement techniques, is introduced and aimed at undergraduate students in Industrial Engineering (IE) to learn a basic procedure for designing and implementing takt production in terms of the Toyota Production Systems (TPS). Students are split into small groups in a class. A series of experiments is designed and performed for an assembly line of magnetic contactors. Using the concept of the TPS, students perform work measurement studies including time study, process design, such as line balancing, and execute simulation experiments. At the end of the course, the teaching staff evaluates each group based on the performance of the simulation results. [ABSTRACT FROM AUTHOR]

Among the technologies for middle-pressure and low-pressure energy recovery, the influence of guide vane is generally neglected in pump as turbine (PAT) based on centrifugal pumps. For high-pressure energy recovery technology, only few studies have been conducted on PAT with guide vane, and the dynamic and static flow laws between the inverse impeller and guide vanes remain unclear. In this study, by optimizing the key geometric parameters of the impeller with forward-curved blades, the influence of different parameters on its performance was investigated. Results show that when the number of blades is 10 at the same flow rate, the highest efficiency is achieved and the internal flow becomes stable. With the same number of blades, the total head increases gradually with the increase of flow rate, whereas the efficiency increases initially and then decreases. Under the same head, the PAT model with blade outlet angle achieves the highest efficiency, power and the best hydraulic performance. Conclusions obtained in this study have important value for implications to optimize the cavitation of multi-stage PAT. [ABSTRACT FROM AUTHOR]

Due to the higher competition in automobile industry, automotive part manufacturers who supply parts have also been challenged to improve the quality of their products to meet customers' requirements. Quality of parts or products could be controlled and improved since the stage of production process design. Efficient production process design could reduce work in process (WIP), wastes, reworks, errors, and failures, which could reduce system cost and increase quality of final products. However, production process design for the process which implements automatic systems is sophisticate due to the complication of the equipment itself and the synchronization requirement. This study presents the use of computer simulations to design an automotive part production process. Two objectives are proposed. The first one is to introduce three dimension robot (3D CAD) simulation for robotic work stations designed to meet the desired cycle time with minimum chance of robot collision and minimum number of robots in the system. The second one is to propose plant simulation for production planning design in order to produce product which could meet the desired capacity and customer needs with minimum number of workers. [ABSTRACT FROM AUTHOR]

The article deals with the use of computer simulation approach in order to streamline production logistics within a specific production company. The computer simulation from its very beginnings has undergone a long and significant evolution. The current possibilities of computer simulation approach enable to mimic the real processes of production logistic activities as well as of the actual production. This article is focused on the question, how to effectively utilise the available tools of computer simulation approach to analyse and streamline a particular simulation system. Therefore also the presented solution is the actual description of a practical application of a computer simulation approach used for the needs of one specific production company within one specific industry area. The intention is to showcase the practical aspects of simulation modelling, in this case utilising the EXTENDSIM simulation system. The simulation approach will be used for the needs of a production company, that produces car components and accessories made of wood for the automotive industry. [ABSTRACT FROM AUTHOR]

Powerful new features may be incorporated to simulation environments by exploiting existing Web technology. To demonstrate this, WebManSim, a prototype web-based manufacturing system simulator has been developed. The proposed system includes project management principles, supports communication and voting and provides workflow facilities and simulation program generation - execution capabilities. Such a system provides close monitor to the evolution of the simulation project, enhances the coordination and communication of the simulation participants, identifies and resolves conflicts that may arise in the simulation team and creates virtual simulation expert communities. The use of such a system may improve the simulation team coordination by automatically initiating project tasks as soon as possible, reduce the project duration by eliminating dead time between activities and decrease the overall simulation project cost by minimizing the face-to-face meetings especially when used by project teams located at geographically remote places. [ABSTRACT FROM AUTHOR]