Ana Luísa Ramos

Model-Based Systems Engineering: An Emerging Approach for Modern Systems

To engineer the modern large, complex, interdisciplinary systems-of-systems (SoS), the collaborative world teams must “speak” the same language and must work on the same “matter.” The “matter” is the system model and the communication mechanisms must be supported by standard, flexible, and friendly modeling languages. The evolving model-based systems engineering (MBSE) approach is leading the way and is expected to become a standard practice in the field of systems engineering (SE) in the next decade. As an emerging paradigm for the systems of the 21st century, it seems useful to overview its current state of the art concerning the developing standards, the embryonic formalisms, the available modeling languages, the methodologies, and the major applications.

Combining heuristic procedures and simulation models for balancing a PC camera assembly line

In this paper, a mixed-model PC camera assembly line balancing case study is presented. The aim of the study is to establish different line configurations, for varying levels of demand. In the first stage of the study, a heuristic procedure previously developed by some of the authors, based on the simulated annealing meta-heuristic, is used to derive line configurations with a minimum number of workstations and a smooth workload balance between and within the workstations. In the second stage, the solutions provided by the heuristic are used as an input to discrete event simulation models in which certain manufacturing parameters that analytical procedures have difficulty to accommodate, namely, stochastic times, machine breakdowns, rework, etc. are introduced. These simulation models derive different performance measures (e.g. flow times and resources utilization) that provide operational support and help fine-tune the line configurations. This paper reports on the collaborative study between the Department of Economics, Management and Industrial Engineering of University of Aveiro and a major manufacturer of electronic consumer goods.

Using simulation for manufacturing process reengineering: a practical case study

This paper presents a simulation study carried out to solve a problem of manufacturing process reengineering. The specific company in which the study took place is a medium size manufacturer of chest freezers, which required an in-depth analysis of its manufacturing operations in an attempt to increase its throughput and overall productivity. A simulation model of the current manufacturing system was developed to ascertain its limitations and problems. The relevant operational performance measures were analyzed in order to allow for the proposal of a set of changes to the actual manufacturing operations. In order to support the decision process concerned with the implementation of the suggested changes, these were included in the simulation model. The outcome of the simulation study was taken into account by the decision-makers and the recommendations are being implemented.

Intelligent urban traffic: A guide through micro modelling approaches

The local authorities have a fundamental role in improving the traffic & environment system of their urban jurisdictions. Locally developed tailor-made solutions, based on active public participation processes, are essential to make the city more attractive, cleaner and healthier thus, a better place to live, work, and play. This challenge, of sustainable urban transportation, demands a comprehensive holistic approach able to cope with the complexity, multidisciplinarity, and socio-technical dimension of the system-of-interest. The environmental aspect of sustainability is critical being at the agenda of the modern world. Modelling the traffic and the related environmental impacts at the micro level is decisive to describe adequately the urban dynamics, to provide personalized real-time information, to test Intelligent Transportation Systems strategies and evaluate their impacts, and to support accurate decision-making processes. This work highlights the relevance of this micro modelling approach, particularly for traffic & air quality, providing a guide through the existing modelling approaches and suggesting the appropriated models and tools to undertake the green mission.

Present and Future Languages – How Innovation Has Changed Us

Given the growth in usage of online social networks, such as Facebook, YouTube, Instagram and Snapchat, which rely on videos and images (such as photos) to relay information between connections, new intuitive languages, though not yet formally recognized, have emerged. We also herein give the example of a new language we have created – the Business Narrative Modelling Language (BNML) – which communicates business perspectives based on pictorial representations, supported by the narrative. Currently, the concept of language is linked to the use of words. We foresee that such a definition of language will have to change to include other structured forms of communication, resorting and relying on graphics, also. We give examples of BNML representations, with regards to two case studies we have performed, based on face-to-face interviews and company visits. At ExpressGlass technology plays an important role, while at Yazaki Saltano a remarkable team effort between Toyota suppliers is made evident, to create innovation.

Improving the Production Performance and Ergonomic Aspects Using Lean and Agile Concepts

RESEARCH ARTICLE Improving the Production Performance and Ergonomic Aspects Using Lean and Agile Concepts Marlene Ferreira Brito, Ana Luísa Ferreira Andrade Ramos, Paula Carneiro, Maria Antónia Gonçalves, José António de Vasconcelos Ferreira and Ana Beatriz Tavares Frade Research Center of Mechanical Engineering (CIDEM), DEGEIT University of Aveiro, Aveiro, Portugal GOVCOPP Research Centre, DEGEIT – University of Aveiro, Aveiro, Portugal ALGORITMI Centre, University of Minho, Braga, Portugal Research Center of Mechanical Engineering (CIDEM), ISEP Polytechnique of Porto, Porto, Portugal DEGEIT – University of Aveiro, Aveiro, Portugal

Integration of lean manufacturing and ergonomics in a metallurgical industry

Striving to improve productivity, industries have used different management approaches, being lean manufacturing the most used over recent years. Lean manufacturing is based on value creation for the customer and elimination of waste that occurs during the production process, while improving working conditions. The incorporation of ergonomic aspects in the workstation design also contributes for the referred objectives, since it will reduce awkward postures or excessive effort during work, leading to better working conditions and increased productivity. The present study highlights, through a case study in four production areas of a metallurgical industry, the benefits of using an integrated operations management approach to improve productivity and ergonomic aspects. Several ergonomic methods, such as Rapid Upper Limb Assessment (RULA), Strain Index (SI), and Rapid Entire Body Assessment (REBA), were chosen to evaluate the ergonomic situation and lean manufacturing tools such as Value Stream Mapping (VSM) and 7 wastes were also used to analyze the systems and increase the productivity by eliminating several wastes. The results of this study show that it is possible, and desirable, to consider both aspects, ergonomic conditions and productivity, during continuous improvement’ implementations. In fact, the improvements reached through the advances in ergonomic conditions can contribute very positively for productivity increasing.

Ergonomic design intervention in a coating production area

The aim of this study is to redesign two workstations in a PVD coating production area, considering productivity and ergonomic aspects. Through the elimination of wastes such as unnecessary movements and transportations and by reducing the awkward postures as arm flexion larger than 45o, the productivity in the loading and unloading workstations increased 9% and 5%, respectively, and the ergonomic risk was improved from medium to acceptable. RULA was the chosen method to evaluate the ergonomic situation and anthropometric studies were performed to find the ideal ergonomic solution. This study shows the importance to consider ergonomic conditions when designing or redesigning a workstation in order to get effective productivity improvements. calized muscle fatigue, and consequently in decreased performance and productivity, and enhanced possibility of operator related health hazards (Corlett et al., 1982). The aim of this work is to answer the research question: “How can be improved the workstation design of loading and unloading processes of a PVD coat production area, considering ergonomic aspects and productivity?” This case study takes place in a PVD coating production area, where workers’ complaints due to shoulder pains were rising considerably. These com-plaints come mainly from the processes of loading and unloading pieces from the suspension, before and after the product entering the PVD machine, respectively. This is a repetitive job and involves several awkward postures such as: flexion of the arms above 45o (from now on “arms up”), trunk flexion, and move manually heavy suspensions. Being such a specific case study, an identical case was not found in the literature. The paper is structured as follows: the section 2 explains the methods used to evaluate the initial situation followed by the methods used to redesign the workstation; section 3 provides a discussion of the main results and section 4 points out some conclusions and recommendations.

A Simulation-Based Analysis of a Gas Filling Process

Simulation models are a powerful engineering tool to analyze the performance of complex systems enabling the comparison of different scenarios and the evaluation of a considerable set of dynamic key performance indicators. This dynamic evaluation supports decision-making by helping operations managers to compare options and to choose the best course of action. This work presents a real-world industry case study illustrating the advantages of using simulation to analyze the current system and evaluate different scenarios of operation. The case study refers to a gas filling process which combines a continuous part (gas tanks’ operation) with a discrete one (filling of gas into the cylinders). The mishmash of continuous and discrete operations is a challenge for modelling & simulation, involving a combined approach not always easy to accomplish. Results lead to the conclusion that the company is able to keep the production levels while reducing the number of dedicated tanks, thus opening up the possibility of exploring other business opportunities.

Improving the productivity of a packaging line using lean manufacturing tools and simulation

This work describes the utilization of lean manufacturing tools and simulation to improve the operations and the productivity of a packaging line of visual communication boards at Bi-silque S.A., one of the most recognized Portuguese companies in its business area. The case study reported in this paper is the outcome of the business internship program sponsored by the Department of Economics, Management and Industrial Engineering of University of Aveiro for the students in the Industrial Management and Engineering master program. The system-in-analysis, the packaging line, is one of the most important lines of the company being in charge of packaging visual communications boards (memos) from several upstream assembly lines. The packaging line was clearly unbalanced and the throughput was below the necessary target (to meet market demand). The operation of the line was stabilized, the main problems were identified and a line balancing action was performed with productivity improvements of about 40%. It was also developed a simulation study, for this line, in order to evaluate the utilization of a material handling robot. The outcome of the study was taken into account by the decision-makers and some recommendations are being implemented. This work is a case study highlighting the advantage of using a experiential learning approach on industrial engineering courses and evidencing the benefits that SMEs can get from the use of lean manufacturing tools and simulation to improve their operations.