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Publications

Publications by CEGI

2019

Application of DOE for the Study of a Multiple Jet Impingement System

Authors
Barbosa, FV; Sousa, SDT; Teixeira, SFCF; Teixeira, JCF;

Publication
COMPUTATIONAL SCIENCE AND ITS APPLICATIONS - ICCSA 2019, PT III

Abstract
Jet impingement is widely implemented in a variety of engineering applications and industrial processes where high average heat transfer coefficients and the uniformity of the heat transfer over the impinging surface are required to enhance the process and to avoid local hot (or cold) spots. Multiple jet impingement involves several parameters that interfere with the performance of the process, and there are no universal optimal solutions. To ensure the optimization of the process, it is important to understand the influence of these parameters in the heat transfer over the target surface. To perform this study an experimental research will be performed on a purpose-built test facility which has been commissioned, using a Particle Image Velocimetry system. However, to reduce time and costs associated to the experimental tests, it is important to perform a Design of Experiments, that allows to reduce the number of trials, focusing on the parameters that have a greater influence on the process performance. Taguchi’s method allows the optimization of the process through the selection of the most suitable parameters values. This work presents the method that must be followed before the development of experiments related to the multiple jet impingement over a complex surface, from the design of the experimental setup to the design of the matrix of experiments. © 2019, Springer Nature Switzerland AG.

2019

New product development-processes in the fashion industry: Evidence from Indonesian Islamic fashion companies

Authors
Sari R.P.; Asad N.;

Publication
Journal of Islamic Marketing

Abstract
Purpose: The purpose of this paper is, first, to examine the design requirements of Islamic fashion in the new product-development process; second, to explore the different practices of new product-development activities from successful and unsuccessful new product lines; and third, to investigate the sequence of the new product-development practice in the fashion industry, specifically the Islamic fashion industry in Indonesia. Design/methodology/approach: Questionnaires were distributed and semi-structured interviews were conducted to collect information regarding the practice of the new product-development activities. The Mann–Whitney U test was performed based on the quality of the new product-development activities of 100 Islamic fashion firms, including five innovative companies that had won several awards in Indonesia. An analysis of the extent to which fashion firms were engaging in new product-development activities provided a more detailed picture of the sequence of those activities. Findings: Islamic norms were adapted during the early design and promotional phases of new product development in Islamic fashion. Various choices of design and colour in Islamic fashion were also perceived as a way of preaching to women to dress more accordingly to the Islamic norm. The new product-development activities that were conducted differently for successful vs unsuccessful new product lines were idea conceptualisation, market analysis, technical and engineering analysis, financial analysis and commercialisation. The commercialisation phase was given the least priority of all the activities. Nevertheless, it contributed to the very first communication to the customers about new product lines. Originality/value: This study makes an important contribution to the deeper and more detailed research on how Islamic fashion companies perceive Islamic values during new product developments and how they perform new product-development activities between successful and unsuccessful products.

2019

RESOURCES FOR TWO-DIMENSIONAL (AND THREE-DIMENSIONAL) CUTTING AND PACKING SOLUTION METHODS RESEARCH

Authors
Oliveira, Ó; Gamboa, D; Silva, E;

Publication
Proceedings of the 16th International Conference on Applied Computing 2019

Abstract

2019

Optimization of the cold profiling process through SMED

Authors
Vieira, T; Sá, JC; Lopes, MP; Santos, G; Felix, MJ; Ferreira, LP; Silva, FJG; Pereira, MT;

Publication
29TH INTERNATIONAL CONFERENCE ON FLEXIBLE AUTOMATION AND INTELLIGENT MANUFACTURING (FAIM 2019): BEYOND INDUSTRY 4.0: INDUSTRIAL ADVANCES, ENGINEERING EDUCATION AND INTELLIGENT MANUFACTURING

Abstract
In a more and more competitive and industrialized market, it is essential that companies realize that the way forward must go through the optimization of their production processes, reducing the costs and increasing product quality. Nowadays it's necessary to adopt innovative management models that can provide increased productivity at minimal costs, such as the Lean thinking. The metalworking industry is integrated into one of the most competitive existing markets in Portugal. Given this, it's fundamental to reduce the waste in all sectors of the production process, using the good Lean principles and practices, such as the Single Minute Exchange of Die, also known as SMED methodology. This paper presents a project of implementing the SMED methodology in the cold profiling process, in a population of five different profiling machines. The results of the SMED implementation show an average OEE improvement of 10,8%.

2019

A methodology to determine size and shape of plots for sugarcane plantation

Authors
Cherri A.C.; Vianna A.C.G.; Ramos R.P.; De Oliveira Florentino H.;

Publication
Scientia Agricola

Abstract
Brazil is the largest sugarcane producer in the world and the leader in the production of sugar and ethanol. Although sugarcane has become an important factor in the Brazilian economy, cultivation has presented many issues, for example, the problems due to burning before the manual harvest. The Brazilian authorities have approved a law that prohibits this practice and mechanized harvesting has thus become the most fitting approach. Given this development, areas for sugarcane plantation must be properly rebuilt to accommodate the new way of harvesting. The main characteristic demanded of sugarcane plots to use harvesting machines is that they must be rectangular. In the present paper, we propose a methodology for dividing the plantation area into plots and planning their allocation so as to accommodate mechanized harvesting. In view of the requirement for plots to be rectangular, we represented this problem as a two-dimensional cutting problem, and to find a solution we adopted the AND/OR graph approach. The computational experiments were conducted using real cases, and the proposed strategy was shown to perform well.

2018

A new load balance methodology for container loading problem in road transportation

Authors
Ramos, AG; Silva, E; Oliveira, JF;

Publication
EUROPEAN JOURNAL OF OPERATIONAL RESEARCH

Abstract
The load balance aspect of the Container Loading Problem (CLP) has been handled in an simplified way in the literature. Either load balance has been treated as a soft constraint or the geometrical centre of the container has been assumed to be the ideal location for the centre of gravity of the cargo, or both, which does not meet regulatory directives and transportation legislation. In this paper, we treat load balance as a 'hard constraint and adopt vehicle specific diagrams that define the feasibility domain for the location of the centre of gravity of the cargo, according to the vehicle specific technical characteristics, thus fulfilling and complying with real-world regulations and legislation. We propose a multi-population biased random-key genetic algorithm (BRKGA), with a new fitness function that takes static stability and load balance into account. Extensive computational experiments were performed with different variants of the proposed approach. Also solutions taken from the literature were evaluated in terms of load balance. The computational results show that it is possible to obtain stable and load balanced solutions without compromising the performance in terms of container volume utilization, and demonstrate also the advantage in incorporating load balance in the packing generation algorithm.

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