Abstract
In this paper, we present beam search heuristics for the single machine scheduling problem with quadratic earliness and tardiness costs, and no machine idle time. These heuristics include classic beam search procedures, as well as filtered and recovering algorithms. We consider three dispatching heuristics as evaluation functions, in order to analyse the effect of different rules on the performance of the beam search procedures. The computational results show that using better dispatching heuristics improves the effectiveness of the beam search algorithms. The performance of the several heuristics is similar for instances with low variability. For high variability instances, however, the detailed, filtered and recovering beam search (RBS) procedures clearly outperform the best existing heuristic. The detailed beam search algorithm performs quite well, and is recommended for small-to medium-sized instances. For larger instances, however, this procedure requires excessive computation times, and the RBS algorithm then becomes the heuristic of choice. Journal of the Operational Research Society (2010) 61, 620-631. doi: 10.1057/jors.2008.191 Published online 18 March 2009

Abstract
Purpose - The purpose of this paper is to obtain pertinent information pertaining to benefits accomplished, main difficulties felt, and key lessons learned in the implementation of lean Six Sigma (LSS), which are likely to be helpful to financial services organizations wanting to implement the same tool. Design/methodology/approach - This paper reports the results of a case study from a financial services organization which has begun the implementation of LSS methodologies ten years ago, in the pursuit of service excellence. Findings - The benefits derived from LSS implementation, such as lowering the operational costs, improving processes and product quality, increased efficiency, which leads to the increase of productivity, the agility and versatility obtained by the organization, vastly outweigh the costs. At an international level, there are cultural differences pertaining mainly to internal resistance and openness to change. Research limitations/implications - This work focuses on a specific case study. Practical implications - The authors compiled the lessons learned and recommendations for future implementations of this methodology. The paper, therefore, will be of interest to managers of similar companies. Originality/value - The paper presents a successful application of LSS for a financial services company. © Emerald Uroup Publishing Limited.

Abstract
Purpose – The purpose of this paper is to analyse annual reports as media of intellectual capital disclosure (ICD) by Portuguese listed companies and to evaluate size, industry and time effects on disclosure as well as the effects of ICD on the growth of a company. Design/methodology/approach – The paper examines ICD in 2004, 2006 and 2008 annual reports using content analysis. Non?parametric statistical methods are used to test size and industry effects on disclosure, the effects of the level of disclosure on the growth of a company and to determine the significance of the differences in disclosure between the years under analysis. Findings – The analysis showed that size is significant in explaining ICD. The results also indicated that industrial affiliation is only partially a factor explaining ICD. It was not possible to confirm neither an increase in ICD over time, nor the relationship between ICD and growth. 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 – This paper adds to the scarce research on ICD by Portuguese companies by providing new empirical data. © 2010, Emerald Group Publishing Limited

Abstract
The BRS can be quantified as the slope between SBP and RR values identified in baroreflex events, estimated by ordinary least squares (OLS) minimization. Quantile regression (QR) is a more robust procedure than OLS and allows a more complete characterization of the data, by estimating conditional functions for different quantiles of interest. In this work, OLS and QR for BRS estimation are compared regarding slope estimates and dispersion. The EuroBaVar results indicate that OLS slope and QR slopes at different quantiles do not exhibit significant differences. Also, OLS and QR slopes require similar number of beats to achieve a given BRS precision in stationary recordings. Finally, BRS estimated with OLS exhibit relative dispersion lower than 10% and 5% when computed from stationary recordings of approximately 3 and 9 minutes length, respectively.

Abstract
One of the classical problems in the structural optimization field is the Truss Topology Design Problem (TTDP) which deals with the selection of optimal configuration for structural systems for applications in mechanical, civil, aerospace engineering, among others. In this paper we consider a TTDP where the goal is to find the stiffest truss, under a given load and with a bound on the total volume. The design variables are the cross-section areas of the truss bars that must be chosen from a given finite set. This results in a large-scale non-convex problem with discrete variables. This problem can be formulated as a Semidefinite Programming Problem (SDP problem) with binary variables. We propose a branch and bound algorithm to solve this problem. In this paper it is considered a binary formulation of the problem, to take advantage of its structure, which admits a Knapsack problem as subproblem. Thus, trying to improve the performance of the Branch and Bound, at each step, some valid inequalities for the Knapsack problem are included.

Abstract
We consider the Weight-constrained Minimum Spanning Tree problem (WMST). The WMST aims at finding a minimum spanning tree such that the overall tree weight does not exceed a specified limit on a graph with costs and weights associated with each edge. We present and compare, from the computational point of view, several formulations for the WMST. From preliminary computational results we propose a model that combines a formulation similar to the well known Miller-Tucker-Zemlin formulation with the cut-set inequalities.