11 research outputs found
A Decision Support System for the Design of Cellular Manufacturing Systems: Database Conceptualization
AbstractIn Cellular Manufacturing Systems (CMS) resources are grouped to create independent cells capable of completely processing a set of similar parts. The design of such a system is complex and entails several interconnected problems. The decision process regarding the design of CMS must, therefore, be sustained by solid data and supported by adequate models capable of helping the decision maker in the development of an adequate solution. In this context, a Decision Support System (DSS) for the design of CMS is being developed, and the purpose of this work is to present the conceptualization of the database required for such DSS
Planeamento de sistemas de produção celulares
Doutoramento em Gestão IndustrialUm sistema de produção celular (SPC) consiste numa forma de organização
dos recursos produtivos sendo estes agrupados em células independentes,
dedicadas ao processamento de famílias de componentes com necessidades
de processamento similares.
Estes sistemas podem ser implementados de duas formas: fisicamente e
logicamente. No primeiro caso as máquinas são dispostas em células de
fabrico de maneira a melhorar a eficiência da implantação em termos de fluxo,
no segundo caso as máquinas são afetadas a famílias de componentes,
formando células virtuais não sendo, contudo, a sua localização física alterada.
Neste trabalho são apresentados os problemas associados à definição de um
sistema de produção celular, nomeadamente nas fases de planeamento,
controlo e avaliação.
Devido à complexidade e ao impacto no desempenho da organização das
decisões tomadas na fase de planeamento do sistema produtivo, os problemas
inerentes a um projeto desta natureza são aprofundados, sendo apresentados
algoritmos para a resolução dos mesmos.
Os procedimentos desenvolvidos tratam os seguintes problemas: (i) formação
de células de fabrico, (ii) balanceamento de células de fabrico, (iii) formação de
células virtuais numa implantação funcional, (iv) formação de células virtuais
numa implantação distribuída, e (v) projeto da implantação fabril considerando
secções com configuração geométrica fixa.
Dada a natureza combinatória dos problemas considerados, foram utilizadas
metaheurísticas na sua resolução.
A principal contribuição deste trabalho para a investigação no planeamento de
sistemas de produção celulares resulta do facto de os modelos e heurísticas
desenvolvidos incluírem um conjunto de aspetos de grande relevância para a
sua aplicação a ambientes industriais, ultrapassando algumas das limitações
práticas inerentes a outros procedimentos reportados na literatura relevante.A cellular manufacturing system (CMS) is a type of production system that
organizes the production resources into independent cells taking into account
the similarities in the manufacturing sequences of the different parts assigned
to those cells.
This type of production system can be implemented in two ways: physically or
logically. In the first situation, machines are grouped into cells with the purpose
of improving the layout efficiency in terms of flow. In the second option,
machines are allocated to part families, originating virtual cells, but their
physical location is not altered.
The first part of this work consists in a revision of the problems associated to a
cellular manufacturing system, namely regarding its design, control and
evaluation.
The problems inherent to the design phase are analyzed with greater detail due
to their importance and impact on the system’s performance.
Due to the complexity and significance of those problems, they were further
analysed and algorithms were developed in order to contribute to their solution.
The models address the following problems: (i) cell formation, (ii) production
cell balancing, (iii) virtual cell formation in a functional layout, (iii) virtual cell
formation in a distributed layout, and (v) facility layout considering objects with
a fixed geometric shape.
Due to the combinatorial nature of the problems, metaheuristics were used in
order to solve them.
The main contribution of this work, towards the furthering of investigation in
cellular manufacturing systems design, derives from the development of
models and heuristics that include a set of features that are highly relevant for
its implementation in a real world industrial setting, overcoming, in this way,
some of the practical limitations inherent to other known procedures
Development of synchronized logistics scenarios
Internal Logistics is the industrial department responsible, within an organization, for overseeing the information flow and for controlling the physical movements of materials in the warehouse, factory and between workstations. Currently the improvement of Internal Logistics processes is a key factor for delivering products to customers on time and at a competitive price. There is an increasing need for eliminating non-value added tasks and reducing operating costs. In this context, the synchronization of supply routes is very important in order to create standards and improve the use of resources. The purpose of this study is to describe the way Logistics Scenarios were developed in an industrial environment and also to show the importance of Internal Logistics.Interna logistika je industrijski departman koji je odgovoran, unutar organizacije, za nadzor protoka informacija i za
kontrolu fizičkog pomeranja materijala u skladištu, fabrici i među radnim stanicama. Trenutno, poboljšanje procesa
interne logistike predstavlja ključni faktor isporuke proizvoda potrošačima na vreme i po konkurentskoj ceni. Postoji
sve veća potreba za eliminisanje zadataka koji ne donose vrednost i smanjenje operativnih troškova. U ovom
kontekstu, sinhronizacija maršuta nabavke je veoma važna kako bi se stvorili standardi i poboljšalo korišćenje
resursa. Svrha ove studije je da se opiše način na koji se logistički scenariji razvijaju u industrijskom okruženju, kao
i da se pokaže značaj interne logistike
Selecting an open-source framework: a practical case based on software development for sensory analysis
The use of frameworks based on Free Open-Source Software (FOSS) has become a viable alternative in the software development process, when compared with Proprietary Software or Closed Source Software. Given that the quality of Open-Source Software (OSS) products varies widely, the careful evaluation of such frameworks, according to a set of requirements, is an important step in the software development process. This work presents the evaluation of some open-source frameworks in order to find the most suitable one for developing a Decision Support System (DSS) to use in Sensory Analysis. This DSS is being designed to support the evaluation of Tasting Panels in sectors where Sensory Analysis is used to assess products’ quality.
The methodology used, based on content analysis in Online Collaborative Spaces, proved to be appropriate to achieve the objectives of this study and therefore, can be extended to select OSS in other areas. Thus, the result of this work is valuable not only for researchers on trends in the OSS area, but also for software developers that intend to implement DSS using FOSS
Modelling forest fire spread through discrete event simulation
First Online: 07 January 2024Forest fires are becoming a more common occurrence in Portugal as well as worldwide. To extinguish or reduce them more quickly and effectively, it is crucial to understand how they spread. This paper presents a study and a model that shows how wildfires spread, assuming the forest can be represented by a graph, where the nodes correspond to forest stands and the arcs to the path between them. In order to do this, algorithms were developed in Python, using discrete event simulation, that allow modelling the progression of the fire on the graph. This fire propagation model takes into account several aspects of the forest, the wind being the most influential one. Some tests were performed, considering different ignition points, wind directions and wind speeds.This work was supported by the Portuguese National Funding Agency for Science, Research and Technology (FCT), within the Center for Research and Development in Mathematics and Applications (CIDMA), project UIDB/04106/2020; and through project PCIF/GRF/0141/2019-An Optimization Framework to reduce Forest Fire
SMART-QUAL: a dashboard for quality measurement in higher education institutions
Purpose – The paper aims to define a dashboard of indicators to assess the quality performance of higher education institutions (HEI). The instrument is termed SMART-QUAL.
Design/methodology/approach –Two sources were used in order to explore potential indicators. In the first step, information disclosed in official websites or institutional documentation of 36 selected HEIs was analyzed. This first step also included in depth structured high managers’ interviews. A total of 223 indicators emerged. In a second step, recent specialized literature was revised searching for indicators, capturing additional 302 indicators.
Findings – Each one of the 525 total indicators was classified according to some attributes and distributed
into 94 intermediate groups. These groups feed a debugging, prioritization and selection process, which
ended up in the SMART-QUAL instrument: a set of 56 key performance indicators, which are grouped in 15
standards, and, in turn, classified into the 3 HEI missions. A basic model and an extended model are also
proposed.
Originality/value – The paper provides a useful measure of quality performance of HEIs, showing a holistic
view to monitor HEI quality from three fundamental missions. This instrument might assist HEI managers for
both assessing and benchmarking purposes. The paper ends with recommendations for university managers
and public administration authorities
Applying value stream mapping to eliminate waste: a case study of an original equipment manufacturer for the automotive industry
Since its beginning, lean manufacturing has built a worldwide reputation based on results related to production improvement and cost reduction in several companies. This management philosophy focuses on customer value creation through the elimination of production wastes. Lean methods and techniques have spread their scope from the automotive industry to a wide range of industries and services. This article presents a case study that describes the use of the lean tool value stream mapping in the production process of automotive parts for a major automotive company. At the beginning of the project, relevant data from the process were collected and analysed. Subsequently, the initial process was mapped, the related wastes were identified, and then future processes were mapped and financial results were estimated. The proposals were presented on kaizen meetings, the action plan was discussed and the decision regarding which option to choose was taken. Consequently, the Cycle Time and the level of the workforce were reduced, the process was improved and savings were obtained
Industrial engineering and management: what and how to teach and learn in an introductory course
Industrial Engineering and Management (IEM) is a field of engineering highly relevant for today’s world challenges, with professionals specially trained to improve processes and systems by striving to eliminate all sources of waste while aiming for continuous improvement.
However, students entering IEM undergraduate programmes across Europe experience difficulties in fully understand what IEM is, the fundamental areas it encompasses, and the roles graduates will perform in their future professional lives. This situation makes it relevant for IEM undergraduate students to have in the first semester of their first year an introductory course to IEM, opening-up some ideas for future roles after graduation and increasing their motivation levels to become IEM professionals able to contribute to a sustainable future.
The aim of this work is to share the authors’ experience throughout the development and implementation of such an introductory course, at the University of Aveiro (UA), Portugal, where innovative teaching and learning methodologies were used.
By combining expositive and ‘hands-on’ classes, and emphasising students’ group work under a Challenge Based Learning (CBL) approach, the first steps to offer students a sound, dynamic, interactive and broad introduction to IEM were taken. The use of assignments as part of the evaluation, as well as the use of games and flipped learning, also contributed to the development of students’ soft skills such as oral and written communication, teamwork, and critical thinking. Overall, it was possible to design a course both appealing and relevant to help students get in touch with IEM since they enter the undergraduate programme.publishe
Modelação e Simulação de uma Linha de Produção de Painéis Solares
O estudo de caso “Modelação e Simulação de uma Linha de Produção de
Painéis Solares” foi desenvolvido em ambiente industrial e resultou de uma
colaboração entre uma PME portuguesa da área das energias renováveis e a
Universidade de Aveiro (Departamento de Economia, Gestão e Engenharia
Industrial). O seu principal objetivo foi o de analisar uma linha de produção
de painéis solares fotovoltaicos no sentido de apoiar decisões operacionais
relacionadas com um desejado aumento da capacidade produtiva da referida
linha.
Os decisores (elementos da equipa de gestão da PME) pretendiam dar
resposta a um aumento verificado na procura de painéis solares e, como tal,
desejavam averiguar se um conjunto de alterações a introduzir na respetiva
linha de produção, que já discutiam há algum tempo, poderia aumentar o
seu volume de produção. Para tal foi inicialmente realizada a modelação do
sistema usando a linguagem gráfica SysML (Systems Modeling Language)
sendo, de seguida, desenvolvido um modelo de simulação por forma a testar
e analisar dinamicamente o desempenho do sistema produtivo face à
introdução das alterações pretendidas.
Após validação do modelo de simulação do sistema atual definiu-se o
cenário alternativo a testar (correspondente às alterações a introduzir na
linha) e analisaram-se os resultados associados a cada um destes cenários.
Todos os modelos de simulação desenvolvidos foram acompanhados pelos
respetivos modelos de animação que permitiram visualizar, de um modo
apelativo, o comportamento dinâmico da linha de produção e comunicar os
resultados de um modo mais eficiente.
Os resultados obtidos permitiram apoiar o processo de decisão e
evidenciaram, perante os decisores, as vantagens da utilização de modelos de
engenharia (modelos gráficos e de simulação) para analisar situações reais
complexas. A empresa identificou-se com os modelos gerados e com os
resultados obtidos. Esses resultados estão a ser utilizados para fazer
pequenos ajustes aos investimentos inicialmente previstos e para introduzir
as modificações na linha de produção de painéis solares fotovoltaicos. Os
objetivos da Universidade foram também alcançados uma vez que o projeto
foi completado com sucesso e os resultados do mesmo estão a ser utilizados
pela empresa para melhorar o seu desempenho
Analysis and design of a project management information system: practical case in a consulting company
Nowadays, due to globalization, business diversification and a growing number of different business projects, the need to support people involved in tasks related to project management is becoming increasingly important. Timely and accurate data about projects’ plans, their progress and related costs, are extremely important for project managers and consequently for assuring the success of the project. In this context, Project Management Information Systems (PMIS) are commonly viewed as an important tool for project management. However, this kind of Information Systems (IS) is relatively expensive and therefore out of reach for many small and medium enterprises (SME) that often choose not to use them. As a way to overcome this situation many consulting companies decide to invest in the development of their own PMIS. This paper presents the design process of an Information System for Project Management, whose main purpose is to manage investment projects throughout their life cycle. The system supports all the application process for incentive programs, as well as the documentation and procedures required, and helps to manage the project itself, when it is approved. This solution will thus contribute to the improvement of the performance of the Projects & Incentives’ division of the consulting company, but can also be replicated by other companies that have similar needs