Abstract
In this paper, we consider the single machine scheduling problem with linear earliness and quadratic tardiness costs, and no machine idle time. We present heuristic algorithms based on the beam search technique. These algorithms include classic beam search procedures, as well as the filtered and recovering variants. Several dispatching rules are considered as evaluation functions, to analyze the effect of different rules on the effectiveness of the beam search algorithms. The computational results show that using better rules improves the performance of the beam search heuristics. The detailed, filtered beam search (FBS) and recovering beam search (RBS) procedures outperform the best existing heuristic. The best results are given by the recovering and detailed variants, which provide objective function values that are quite close to the optimum. For small to medium size instances, either of these procedures can be used. For larger instances, the detailed beam search (DBS) algorithm requires excessive computation times, and the RBS procedure then becomes the heuristic of choice.

Abstract
In this paper, we present greedy randomised dispatching heuristics for the single-machine scheduling problem with quadratic earliness and tardiness costs and no machine idle time. The several heuristic versions differ, on the one hand, on the strategies involved in the construction of the greedy randomised schedules. On the other hand, these versions also differ on whether they employ only a final improvement step or perform a local search after each greedy randomised construction. The proposed heuristics were compared with existing procedures as well as with optimum solutions for some instance sizes. The computational results show that the proposed procedures clearly outperform their underlying dispatching heuristic, and the best of these procedures provide results that are quite close to the optimum. The best of the proposed algorithms is the new recommended heuristic for large instances as well as a suitable alternative to the best existing procedure for the larger of the middle-sized instances.

Abstract
This descriptive paper explores the role of Southern European academics within social and environmental accounting (SEA) research. It is the first survey on SEA research in Southern Europe. This review specifically targeted international journals to see how much Southern European research had penetrated the international SE A academic discourse. The research that is reported in this paper is based on an electronic search of the online databases which include journals which publish SEA research. The paper reviews journal articles published in specialized journals over the period 1998 to 2008 and reaches several conclusions: 1. The volume of published research is low and quite recent; 2. Research is more or less evenly split between empirical and theoretical articles; 3. Empirical research is somewhat more qualitative in orientation, and 4. Most empirical papers focus on the countries of origin of the researchers. Hence, there is great scope for expanding the amount of research on SEA in Southern Europe, as well as improving its geographic coverage.

Abstract
The development of automated individualized drug dosage regimens, namely in general anaesthesia environment, has been a subject of interest in the last decades. The use of continuous intravenous drug administration aims at, accurately, maintaining the system at a desired target effect concentration level. Different methods have been proposed for the design of individualized dosage regimens. In this study individual drug dose design is achieved through the characterization of transient initial response induced by a bolus administration of drug. This approach is based on the statistical analysis of the data using Walsh-Fourier spectral analysis which provides information about patient dynamics, allowing the on-line drug dose design using multiple linear least squares and quantile regression technics. The proposed methodology is illustrated in the case where the effect measured on the patient corresponds to the neuromuscular blockade (NMB) level and the drug to the muscle relaxant atracurium.

Abstract
One of the classical problems in the structural optimization field is to find the stiffest truss, under a given load and with a bound on the total volume. This is a well-studied problem for continuous cross sectional areas. Generally, the optimal solutions obtained for this problem contain bars with many different cross sectional areas. However, in real life, only a finite set of possible values for those cross sectional areas can be considered. We propose a Semidefinite Programming with discrete variables for this problem. In order to solve the problem we derive and compare two exact algorithms. The first one is a branch and bound algorithm where the branching is done only on the bar-areas. The second algorithm has two stages. In the first stage a branch and bound on the nodes of the structure is performed. In the second stage, considering the nodes in the structure from the first stage, a branch and bound algorithm on the bar-areas is performed.

Abstract
In this paper we examine prior research, which has been studying the effects of switching costs on customer retention, within online and offline markets. The empirical studies in the area reveal contrasting results: (1) switching costs are a stronger predictor of customer retention than customer satisfaction alone; (2) the main effect of switching costs moderates the relationship between satisfaction and customer retention; (3) conversely, the lack of main effects reflects the interaction effects indicating that switching costs have an even greater impact on customer retention than under satisfaction variation levels. These power asymmetries reveal a conflicting role of switching costs across industry and marketplaces. We also observe a significant bias in favor of service industries with high switching costs. Based on this meta-analytical research we propose a theoretical base to support the path structural relationship between the constructs providing a nomological framework to future research. Finally we draw some conclusions, suggest future research directions and make managerial recommendations. © 2009 IADIS.