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Abstract
In this paper, we consider the single machine scheduling problem with quadratic earliness and tardiness costs, and no machine idle time. We propose a genetic approach based on a random key alphabet and present several algorithms based on this approach. These versions differ on the generation of both the initial population and the individuals added in the migration step, as well as on the use of local search. The proposed procedures are compared with the best existing heuristics, as well as with optimal solutions for the smaller instance sizes. The computational results show that the proposed algorithms clearly outperform the existing procedures and are quite close to the optimum. The improvement over the existing heuristics increases with both the difficulty and the size of the instances. The performance of the proposed genetic approach is improved by the initialization of the initial population, the generation of greedy randomized solutions, and the addition of the local search procedure. Indeed, the more sophisticated versions can obtain similar or better solutions and are much faster. The genetic version that incorporates all the considered features is the new heuristic of choice for small and medium size instances.

Abstract
Purpose: This descriptive paper seeks to explore the role of Portuguese academics within corporate social responsibility and disclosure (CSR&D) research. It aims to give some insight into the nature and the extent of research on CSR&D being undertaken by Portuguese authors. Design/methodology/approach - This review specifically targeted international journals to see how much Portuguese research had penetrated the international business, management and accounting (BMA) academic discourse. The research that is reported in this paper is based on an electronic search of the online databases which include journals in these areas. The paper reviews journal articles published in BMA journals over the period 1998 to 2008. Findings: The paper reaches several conclusions: the volume of published research in international journals is still very low; most papers focus on CSR; research is overwhelmingly empirical in orientation; and most papers focus on Portugal. Hence, there is great scope for expanding the amount of research on CSR&D in Portugal, as well as improving the diversity of its content and its geographical coverage. Research limitations/implications : The paper is not expected to be a complete study, but rather a stimulus for future research. It is intended to provide a basis for comparison with further studies on CSR&D research in Portugal with studies from other geographical areas. Originality/value: The paper provides the first survey on CSR&D research in Portugal. It also provides the first opportunity to reflect on the current state of these still emerging academic fields. © Emerald Group Publishing Limited.

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Purpose: The purpose of this paper is to compare the internet and annual reports as media of intellectual capital disclosure (ICD) and analyse its determinants. Design/methodology/approach: The paper examines ICD on the internet in 2009 and compares the internet and 2008 annual reports as disclosure media using content analysis. Non-parametric statistical methods are used to analyse some factors which influence disclosure. Findings: Portuguese companies attribute greater importance to the internet. The analysis showed that size is significant in explaining ICD only in the case of annual reports. The results also indicated that industrial affiliation is only partially a factor explaining ICD. Research limitations/implications: The sample is small. There may be content analysis issues associated with subjectivity in the coding process and the use of a limited content analysis method. Originality/value: The paper adds to the scarce research on ICD by Portuguese companies by providing new empirical data. This paper is one of the first to investigate ICD both in annual reports and on the internet. © Emerald Group Publishing Limited.

Abstract
This study aims to develop an approach for the management of a forest of maritime pine located in the north region of Portugal. The forest is classified into five public lands, the so-called baldios, extending over 4432 ha. These baldios are co-managed by the Official Forest Services and the local communities mainly for timber production purposes. The forest planning involves non-spatial and spatial constraints. Spatial constraints dictate a maximum clearcut area and an exclusion time. An integer programming model is presented and the computational results are discussed.

Abstract
We consider a real production planning problem occurring in a glass container manufacturing company. The goal is to minimise the average stock level during a planning horizon of one year, maintaining customers satisfaction and keeping the production at its maximum rate. Besides the production capacity, the main constraints considered are related to the number of setup changes in machines, which is restricted in each factory. The main goal is to find the best balance between the number of setups and the average stock level. We propose a decomposition of the problem into two interrelated problems: a lot-sizing problem and a scheduling problem. For each problem we propose a mathematical model that can be solved using a commercial solver package. To be an efficient managerial tool, the method should provide quickly good solutions. Therefore we solve the lot-sizing problem through a relax-and-fix heuristic and discuss the results. Copyright © 2011 Inderscience Enterprises Ltd.