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Article
Publication date: 1 June 2002

Nicholas Alexander and Marcelo de Lira e Silva

This paper considers the development of emerging retail markets with particular reference to Brazil. The South American region has only relatively recently seen the level of…

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Abstract

This paper considers the development of emerging retail markets with particular reference to Brazil. The South American region has only relatively recently seen the level of international retail interest previously seen in other global regions such as East Asia. The paper considers the development of retailing in Brazil and the impact of internationally derived innovation and direct international retail activity in the market. It considers concepts of retail internationalisation in the light of the Brazilian experience. The paper highlights important issues with respect to South America’s place in the evolution of global retailing.

Details

International Journal of Retail & Distribution Management, vol. 30 no. 6
Type: Research Article
ISSN: 0959-0552

Keywords

Article
Publication date: 11 October 2011

Silvana Maria B. Afonso, Bernardo Horowitz and Marcelo Ferreira da Silva

The purpose of this paper is to propose physically based varying fidelity surrogates to be used in structural design optimization of space trusses. The main aim is to demonstrate…

Abstract

Purpose

The purpose of this paper is to propose physically based varying fidelity surrogates to be used in structural design optimization of space trusses. The main aim is to demonstrate its efficiency in reducing the number of high fidelity (HF) runs in the optimization process.

Design/methodology/approach

In this work, surrogate models are built for space truss structures. This study uses functional as well as physical surrogates. In the latter, a grid analogy of the space truss is used thereby reducing drastically the analysis cost. Global and local approaches are considered. The latter will require a globalization scheme (sequential approximate optimization (SAO)) to ensure convergence.

Findings

Physically based surrogates were proposed. Classical techniques, namely Taylor series and kriging, are also implemented for comparison purposes. A parameter study in kriging is necessary to select the best kriging model to be used as surrogate. A test case was considered for optimization and several surrogates were built. The CPU time is reduced when compared with the HF solution, for all surrogate‐based optimization performed. The best result was achieved combining the proposed physical model with additive corrections in a SAO strategy in which C1 continuity was imposed at each trust region center. Some guidance for other engineering applications was given.

Originality/value

This is the first time that physical‐based surrogates for optimum design of space truss systems are used in the SAO framework. Physical surrogates typically exhibit better generalization properties than other surrogates forms, produce faster solutions, and do not suffer from dimensionality curse when used in approximate optimization strategies.

Details

Engineering Computations, vol. 28 no. 7
Type: Research Article
ISSN: 0264-4401

Keywords

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