Using simulation to model the logistic operations of a company of the cement industry

This paper presents a discrete-event simulation model to study the logistics operations involved in a plant of the cement industry, aligned with a real project developed in partnership between Cachapuz (a company that provides international weighing solutions) and the University of Minho. The purpose of this work consists in using simulation to model several activities, involving weighing, loading and unloading of raw materials, regardless of the type of industry, e.g. cement, tomato, cereals. Thus, this paper documents the work conducted to apply the developed simulation model in a case study of the cement industry. After validating the model, a set of simulation experiments were conducted, which allowed to estimate the maximum capacity of the plant and the impact in the performance of the plant, of the arrival of a cargo vessel. In this regard, it was found that in the case study in question, it is not possible to unload all the cargo from the vessel in a working day - around 3 working days would be required. Further conclusions and future work are discussed in the last section.- (undefined

Integrated design of production systems in a lighting manufacturer using CAD and simulation in layout and process optimization

This paper discusses production systems design issues, applied to the production system layout of a manufacturer of lighting fittings and components. In this paper, production systems design software tools – Information Systems, Simulation and Computer Aided Design are integrated, exploring ways of dealing with data diversity and assuring valid and efficient production system layouts, taking advantage of the mentioned data integration. This integration is implemented on Microsoft Access (databases with system knowledge repository), AutoCAD (layout design) and WITNESS (simulation). The software package developed was called IDS (Integrated Design of Systems). This approach can help on global system optimization that considers all important system resources and system performance measures. Solutions are expected to be faster to achieve and better than solutions obtained with non-integrated approaches. IDS approach is open and accessible, thus enabling different companies to use this advanced production systems design tool, taking advantage of simulation and CAD systems and their integration. This application intends to validate the concept and functionalities of the proposed tool, on a real industrial case study.This work has been supported by FCT – Fundação para a Ciência e Tecnologia (algoritmi

Comparison of SIMIO and ARENA simulation tools

The purpose of this paper is to establish a comparison between Simio and Arena, helping a vast community of simulation practitioners to gain access to advanced modelling capabilities to address complex problems. Several aspects were compared, such as: concept of simulation models, animation development, modelling philosophies, Simio libraries and Arena templates, concept of entities, interface of the tools and Simio objects versus Arena blocks. The comparison was consolidated through the analysis of two case studies where the authors aimed to emphasize the way each simulation tool addresses some important issues related to model construction. The several compared aspects indicate the many advantages of using the more recent tool. Thus, this object-oriented tool appears to have all the conditions to trigger a widespread paradigm shift in the way practitioners build models.This work has been supported by FCT – Fundação para a Ciência e Tecnologia in the scope of the project: PEst-OE/EEI/UI0319/2014

Using simio to automatically create 3d warehouses and compare different storage strategies

This paper focuses on a simulation based approach to reduce warehouse costs. At an early stage, the tool needs to be able to generate different types of warehouses. To accomplish this, a Simio add-in was built in C#, using the Simio API, where the user only needs to insert the layout data on an excel spreadsheet. Afterwards, the created warehouse is capable of modelling different storage strategies and compare them. The obtained results indicate that the proposed strategy is able to reduce the picking time in about 15% and the number of stops per milk run in 50%. Moreover, it was found that the strategy currently in use needs 35% more space than the proposed one.This work has been co-supported by SI I&DT project in joint-promotion nº 36265/2013 (HMIEXCEL - 2013-2015 Project) and by FCT – Fundação para a Ciência e Tecnologia in the scope of the project: PEstOE/EEI/UI0319/2014.info:eu-repo/semantics/publishedVersio

3D microsimulation of milkruns and pickers in warehouses using SIMIO

To help the Bosch Car Multimedia Portugal in Ferreiros, Braga to reduce its costs (both in time and space) with its warehouse, a micro simulation model is being developed in Simio. Particularly, the tool needs to be able to model pickers riding milkruns to collect containers of products, from a warehouse, to satisfy the needs of the production lines. In this sense, the storage strategy used on the warehouse, the quantity of requests a picker gets per shift, the time between shifts, the number of types of products, the arrival rate of requests, and the number of milkruns and pickers needs to be adjustable. Additionally, to design the corridors of the warehouse in a configurable way, an Add-in in C#, using the API of Simio, is being developed. Thus, this paper intends to document the first part of the simulation model developed, which consists on the pickers receiving requests and riding their milkruns to collect the respective containers from the warehouse. Five different Simio models compose the main simulation model. Conclusions and future work are discussed.This work has been co-supported by SI I&DT project in joint-promotion nº 36265/2013 (HMIEXCEL - 2013-2015 Project) and by FCT – Fundação para a Ciência e Tecnologia in the scope of the project: PEst-OE/EEI/UI0319/2014

Sustainability Benefits Analysis of CyberManufacturing Systems

Confronted with growing sustainability awareness, mounting environmental pressure, meeting modern customers’ demand and the need to develop stronger market competitiveness, the manufacturing industry is striving to address sustainability-related issues in manufacturing. A new manufacturing system called CyberManufacturing System (CMS) has a great potential in addressing sustainability issues by handling manufacturing tasks differently and better than traditional manufacturing systems. CMS is an advanced manufacturing system where physical components are fully integrated and seamlessly networked with computational processes. The recent developments in Internet of Things, Cloud Computing, Fog Computing, Service-Oriented Technologies, etc., all contribute to the development of CMS. Under the context of this new manufacturing paradigm, every manufacturing resource or capability is digitized, registered and shared with all the networked users and stakeholders directly or through the Internet. CMS infrastructure enables intelligent behaviors of manufacturing components and systems such as self-monitoring, self-awareness, self-prediction, self-optimization, self-configuration, self-scalability, self-remediating and self-reusing. Sustainability benefits of CMS are generally mentioned in the existing researches. However, the existing sustainability studies of CMS focus a narrow scope of CMS (e.g., standalone machines and specific industrial domains) or partial aspects of sustainability analysis (e.g., solely from energy consumption or material consumption perspectives), and thus no research has comprehensively addressed the sustainability analysis of CMS. The proposed research intends to address these gaps by developing a comprehensive definition, architecture, functionality study of CMS for sustainability benefits analysis. A sustainability assessment framework based on Distance-to-Target methodology is developed to comprehensively and objectively evaluate manufacturing systems’ sustainability performance. Three practical cases are captured as examples for instantiating all CMS functions and analyzing the advancements of CMS in addressing concrete sustainability issues. As a result, CMS has proven to deliver substantial sustainability benefits in terms of (i) the increment of productivity, production quality, profitability & facility utilization and (ii) the reduction in Working-In-Process (WIP) inventory level & material consumption compared with the alternative traditional manufacturing system paradigms

Sistema de simulação baseado em agentes usando o V-REP

Atualmente o mercado apresenta elevadas flutuações na procura por produtos personalizados, com baixo custo, alta qualidade e com ciclos de vida curtos. Portanto, as empresas são obrigadas a adaptarem-se aos novos paradigmas de produção para poderem dar resposta às elevadas flutuações na procura e as exigências do mercado. Estas exigências geram nas empresas necessidades de novas soluções para tornarem os sistemas de produção mais ágeis e flexíveis, uma vez que as abordagens tradicionais estão sendo inadequadas. Por forma a tornar os sistemas ágeis e flexíveis surgiram novos paradigmas de produção que oferecem às empresas uma elevada capacidade de adaptação na produção, o que possibilita as empresas dar resposta as elevadas flutuações na procura. Portanto, adicionalmente permite obter menor custo face as abordagens tradicionais. Com o avanço das tecnologias surgiram várias propostas que visam tornar os sistemas de produções mais flexíveis, adaptáveis, evolutivas e escaláveis. Uma dessas propostas são os sistemas multiagentes. Estes sistemas têm carácter distribuídos, auto-organizáveis e capazes de reagir de forma rápida às perturbações ou situações de falhas iminentes das linhas de produção. A inovação e a melhoria contínua na produção levam as empresas de manufaturas a recorrer às tecnologias de simulação para testar, validar e avaliar os seus processos de produção. Neste contexto, é proposta uma arquitetura que visa apresentar uma solução de simulação para sistemas controlados por sistemas multiagentes. Esta arquitetura foi testada usando uma topologia da célula NOVAFLEX. Os resultados comprovam que é possível integrar sistemas multiagente num simulador 3D, possibilitando adaptar os sistemas de produções.Currently, the market has high fluctuations in the demand for customized products, with low cost, high quality and with short life cycles. Just as companies are forced to adapt to new production paradigms in order to respond as high fluctuations in demand for market demands. These demands create a need in companies for new solutions to make production systems more flexible, since traditional approaches are inadequate. In order to develop and flexible systems new production paradigms have emerged for companies with a high capacity for adaptation in production, which enables companies to respond as high fluctuations in demand. Please get cheaper as traditional face. With the advancement of technologies, several proposals have appeared that aim to make production systems more flexible, adaptable, evolutionary and scalable. One such proposal is multi-agent systems. These systems are distributed, self-organizing, and capable of reacting quickly to disturbances or situations of imminent failure of production lines.Innovation and the continuous improvement of technologies in the production areas have led manufacturing companies to use simulation technologies to test, validate and evaluate their production processes. Innovation and continuous improvement in production lead manufacturers to use simulation technologies to test, validate and evaluate their production processes. In this context, it is proposed an architecture that aims to present a simulation solution for systems controlled by multi-agent systems. This architecture was tested using a NOVAFLEX cell topology. The results prove that it is possible to integrate multiagent systems in a 3D simulator, allowing to adapt the production systems

Microssimulação para avaliar o impacto da introdução de pré-semáforos em cruzamentos

Dissertação de mestrado em Engenharia de SistemasA resolução de problemas relacionados com a saturação dos cruzamentos consiste, geralmente, na construção de infraestruturas como pontes e túneis. Estas representam o tipo de soluções mais dispendiosas e, no cenário de crise em que vários países se encontram, torna-se necessário equacionar outro tipo de soluções, de menor custo. Assim, esta dissertação pretende fornecer uma resposta à tese de que é possível melhorar significativamente o desempenho de um cruzamento, através da utilização de pré-semáforos, nos acessos ao mesmo. Para este efeito, foi desenvolvido um modelo de microssimulação de tráfego, usando o SIMIO. Durante o processo de familiarização com esta ferramenta, foi efetuada uma comparação com o Arena. O modelo de tráfego desenvolvido é totalmente parametrizável, sendo possível alterar: o tipo de cruzamento (com ou sem pré-semáforos); a distância entre um pré-semáforo e os respetivos semáforos principais; o tempo de sinal verde dos semáforos e a intensidade de tráfego. Os dados introduzidos para modelar o sistema foram recolhidos através de observações no terreno e da bibliografia consultada. Definiram-se como KPI (Key Performance Indicators): o tempo médio de espera por veículo, o tamanho médio das filas e o fluxo de veículos por hora. Foi usado o modo de experiências de simulação do SIMIO, para avaliar o impacto que as alterações às propriedades do modelo produzem nos KPI. As experiências indicam que o tempo adequado de duração do sinal verde, em cruzamentos com pré-semáforos, se deve situar entre os 20 e os 30 segundos e que o melhor desempenho é atingido quando os pré-semáforos se encontram a 40 metros dos respetivos semáforos principais, contudo, constata-se que, para intensidades de tráfego moderadas ou baixas, a distância não influencia o desempenho do cruzamento. Comparando os desempenhos de um cruzamento com pré-semáforos com o de um com normal semaforização, verifica-se uma subida do teto máximo do fluxo do cruzamento em 15%, uma descida do tempo médio de espera em aproximadamente 1 minuto e 15 segundos e uma descida do tamanho médio das filas em aproximadamente 60 metros. Adicionalmente, também se verificou que existe sempre lucro no espaço ocupado pelas filas, tendo em conta o investimento necessário para implementação de pré-semáforos.The resolution of problems related to the saturation of traffic intersections usually consists in the construction of infrastructure such as bridges or tunnels. These represent the type of solutions most costly and, in the scenario of crisis in which several countries are, it becomes necessary to ponder another type of solution, of lower cost. Thus, this dissertation intends to provide an answer to the thesis that it is possible to significantly improve the performance of a traffic intersection, by using pre-signals, in its approaches. For this purpose, a traffic micro simulation model was developed, using SIMIO. During the process of familiarization with this tool, a comparison was made with Arena. The traffic model developed is completely parametrizable, being possible to change: the type of intersection (with or without pre-signals); the distance between a pre-signal and the respective main lights of each approach; the green light signal time of the traffic lights and the traffic intensity. The input data to model the system were collected through field observations and literature reviewed. The defined KPI (Key Performance Indicators) were: the average waiting time per vehicle, the average size of the queues and the flow of vehicles per hour. To evaluate the impact that changes to the model properties produce on the KPI, the simulation experiences mode of the SIMIO were used. These show that the proper time duration of the green light at traffic intersections with pre-signals should be between 20 and 30 seconds and that the best performance is achieved when the pre-signals are located 40 meters away of the respective main lights, however, it is found that for moderate and low traffic intensities the distance doesn‘t influence the performance of the intersection. Comparing the performance of an intersection with traffic signals with a normal one, it is noted an increase of the upper ceiling of the flow of the intersection in 15%, a decrease in the average waiting time in approximately 1 minute and 15 seconds and a decrease of the average size of the queues in about 60 meters. In addition, it was also found that there is always gain in the space occupied by the queues, taking into consideration the investment needed to implement pre-signals

A multiple channel queueing model under an uncertain environment with multiclass arrivals for supplying demands in a cement industry

In recent years, cement consumption has increased in most Asian countries, including Malaysia. There are many factors which affect the supply of the increasing order demands in the cement industry, such as traffic congestion, logistics, weather and machine breakdowns. These factors hinder smooth and efficient supply, especially during periods of peak congestion at the main gate of the industry where queues occur as a result of inability to keep to the order deadlines. Basic elements, such as arrival and service rates, that cannot be predetermined must be considered under an uncertain environment. Solution approaches including conventional queueing techniques, scheduling models and simulations were unable to formulate the performance measures of the cement queueing system. Hence, a new procedure of fuzzy subset intervals is designed and embedded in a queuing model with the consideration of arrival and service rates. As a result, a multiple channel queueing model with multiclass arrivals, (M1, M2)/G/C/2Pr, under an uncertain environment is developed. The model is able to estimate the performance measures of arrival rates of bulk products for Class One and bag products for Class Two in the cement manufacturing queueing system. For the (M1, M2)/G/C/2Pr fuzzy queueing model, two defuzzification techniques, namely the Parametric Nonlinear Programming and Robust Ranking are used to convert fuzzy queues into crisp queues. This led to three proposed sub-models, which are sub-model 1, MCFQ-2Pr, sub-model 2, MCCQESR-2Pr and sub-model 3, MCCQ-GSR-2Pr. These models provide optimal crisp values for the performance measures. To estimate the performance of the whole system, an additional step is introduced through the TrMF-UF model utilizing a utility factor based on fuzzy subset intervals and the α-cut approach. Consequently, these models help decision-makers deal with order demands under an uncertain environment for the cement manufacturing industry and address the increasing quantities needed in future