Simulation modelling software approaches to manufacturing problems

Increased competition in many industries has resulted in a greater emphasis on developing and using advanced manufacturing systems to improve productivity and reduce costs. The complexity and dynamic behaviour of such systems, make simulation modelling one of the most popular methods to facilitate the design and assess operating strategies of these systems. The growing need for the use of simulation is reflected by a growth in the number of simulation languages and data-driven simulators in the software market. This thesis investigates which characteristics typical manufacturing simulators possess, and how the user requirements can be better fulfilled. For the purpose of software evaluation, a case study has been carried out on a real manufacturing system. Several simulation models of an automated system for electrostatic powder coating have been developed using different simulators. In addition to the evaluation of these simulators, a comprehensive evaluation framework has been developed to facilitate selection of simulation software for modelling manufacturing systems. Different hierarchies of evaluation criteria have been established for different software purposes. In particular, the criteria that have to be satisfied for users in education differ from those for users in industry. A survey has also been conducted involving a number of users of software for manufacturing simulation. The purpose of the survey was to investigate users' opinions about simulation software, and the features that they desire to be incorporated in simulation software. A methodology for simulation software selection is also derived. It consists of guidelines related to the actions to be taken and factors to be considered during the evaluation and selection of simulation software. On the basis of all the findings, proposals on how manufacturing simulators can be improved are made, both for use in education and in industry. These software improvements should result in a reduction in the amount of time and effort needed for simulation model development, and therefore make simulation more beneficial

Construction time-cost model in Croatia

The paper deals with the applicability of the time-cost model for calculating the sustainable construction time for building projects in Croatia. In this model the time is expressed as a function of money in the project, while the specific constants K and B need to be determined. These constants depend on economic characteristics of the country or a larger area, therefore had to be separately calculated for a region with similar economic characteristics. The modelling of the constants was performed for two groups of building projects - the roads and residential and office multi-storey buildings. The obtained results have been analyzed and compared to the corresponding results from abroad

A critical evaluation and comparison of four manufacturing simulators using analytic hierarchy process

In the period of continuous change in global business environment, organizations, large and small, are finding it increasingly difficult to deal with, and adjust to the demands for such change. Simulation is a powerful tool for allowing designers imagine new systems and for enabling them to both quantify and to observe behaviour. Currently the market offers a variety of simulation software packages. Some are less expensive than others. Some are generic and can be used in a wide variety of application areas while others are more specific. Some have powerful features for modelling while others provide only basic features. Modelling approaches and strategies are different for different packages. Companies are seeking advice about the desirable features of software to manufacture simulation, depending on the purpose of its use. Because of this, the importance of an adequate approach to simulation software evaluation and comparison is apparent. This paper presents a critical evaluation of four widely used manufacturing simulators: NX-IDEAS, Star-CD, Micro Saint Sharp and ProModel. Following a review of research into simulation software evaluation, an evaluation and comparison of the above simulators is performed. This paper illustrates and assesses the role the Analytic Hierarchy Process (AHP) played in simulation software evaluation and selection. The main purpose of this evaluation and comparison is to discover the suitability of certain types of simulators for particular purposes

Современные Методологические и Инструментальные Подходы Моделирования Бизнес-Задач

Работа посвящена оценке роли и перспективам использования моделирования при решении бизнес-задач. Выделены современные подходы моделирования, используемые при описании архитектуры, разработке модели деятельности организации и проведении реинжиниринга.. Приведено краткое изложение существующих методологий и инструментальных средств, применяемых в современном бизнес-моделировании

Initial Data and Eccentricity Reduction Toolkit for Binary Black Hole Numerical Relativity Waveforms

The production of numerical relativity waveforms that describe quasicircular binary black hole mergers requires high-quality initial data, and an algorithm to iteratively reduce residual eccentricity. To date, these tools remain closed source, or in commercial software that prevents their use in high performance computing platforms. To address these limitations, and to ensure that the broader numerical relativity community has access to these tools, herein we provide all the required elements to produce high-quality numerical relativity simulations in supercomputer platforms, namely: open source parameter files to numerical simulate spinning black hole binaries with asymmetric mass-ratios; open source $\texttt{Python}$ tools to produce high-quality initial data for numerical relativity simulations of spinning black hole binaries on quasi-circular orbits; open source $\texttt{Python}$ tools for eccentricity reduction, both as stand-alone software and deployed in the $\texttt{Einstein Toolkit}$'s software infrastructure. This open source toolkit fills in a critical void in the literature at a time when numerical relativity has an ever increasing role in the study and interpretation of gravitational wave sources. As part of our community building efforts, and to streamline and accelerate the use of these resources, we provide tutorials that describe, step by step, how to obtain and use these open source numerical relativity tools

Simulação aplicada a manufatura flexivel

Dissertação (mestrado) - Universidade Federal de Santa Catarina. Centro TecnologicoOs sistemas flexíveis de manufatura resultam do desejo de alcançar a produtividade da produção de massa com a agilidade da fabricação por encomenda. Em virtude do grau de automação, da flexibilidade, do número elevado de diferentes produtos fabricados em pequenos lotes, estes sistemas apresentam uma complexidade maior do que os tradicionais. A obtenção da eficiência produtiva destes sistemas envolve otimizar um grande número de variáveis decisórias e solucionar uma problemática variada que vai de problemas de longo prazo, como os de projeto, médio prazo, representado pelo planejamento, curto prazo, identificado pelos problemas de programação e, ainda, por problemas de curtíssimo prazo, relacionados com o controle em tempo-real do sistema. A complexidade destes sistemas fez da simulação senão a única ferramenta para sua análise, pelo menos, a mais importante. Com o barateamento dos custos de hardware e a crescente aceitação da simulação como técnica da solução de problemas, o número de recursos de software relacionados aos SFM cresceu muito além do que qualquer um seria capaz de acompanhar. O propósito deste trabalho é descrever estes sistemas, sua origem, vantagens e problemática, classificando e analisando os instrumentos de software disponíveis possibilitando, desta forma, decisões melhores e mais rápidas por parte de quem pretenda faser uso da simulação para estudá-los

A visual programming system for defining behavior in simulation models of manufacturing systems

A visual programming system is described that allows the modeler full flexibility in defining the behavior of a manufacturing system simulation model. Decision-making behavior of objects in the simulation can be viewed by watching an animation of the system layout, viewing function block diagrams of rules that govern behavior, or noting the progress of an object in carrying out sequences of activities that are pictured as operation networks. Rules, elemental operations and operation networks are structured and associated with particular objects, groups of objects, and locations on the manufacturing system layout. The objective of this system is to reduce the time and expense required to construct and modify models, given that manufacturing system data have been collected.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/44229/1/10479_2005_Article_BF02136835.pd