2009
Autores
Correia, F; Pinhao, S; Poinhos, R; Paz Mendes de Oliveira, BMPM; Vaz de Almeida, MDV; Medina, JL; Galvao Teles, A;
Publicação
OBESITY AND METABOLISM-MILAN
Abstract
Those who work in obesity treatment know that long term success is hard to achieve. The reasons for non compliance in diet therapies are not well understood. In this study, we tried to recognize difficulties and barriers linked to unsuccessful weight reduction. This study was conducted in an outpatient clinic of a central university hospital. 442 overweight patients (371 women and 71 men), with BMI >= 25 kg/m(2), were enquired about diet compliance: a) existence of difficulties; b) difficulty degree (five point scale); 0 barriers of diet therapy (close-ended options). Mean age was 41 years, with SD 13 years. More than half patients mentioned difficulties in the diet maintenance. When asked about the difficulty degree, almost all patients mentioned at least some difficulty with degree 3 "quite difficult" being the most common answer The top five barriers were similar for both genders, but they were differently ranked. Women seem to give more importance to psychological issues. Most overweight patients feel barriers in the compliance of their diet therapy. Although a similar proportion of males and females referred difficulties and similar difficulty degrees regarding their diet therapy, the main difficulty, came from different origins. This enhances the importance of establishing an individual food plan respecting sensorial properties and social environment, together with the patient's habits, psychological condition and motivation, as a way to encourage diet compliance and to achieve success in obesity treatment. Obesity and Metabolism 2009; 5: 107-113.
2009
Autores
Valente, JMS; Goncalves, JF;
Publicação
COMPUTERS & OPERATIONS RESEARCH
Abstract
In this paper, we consider the single machine scheduling problem with linear earliness and quadratic tardiness costs. and no machine idle time. We propose a genetic approach based on a random key alphabet. Several genetic algorithms based on this approach are presented. These versions differ on the generation of the initial population, as well as on the use of local search. The proposed procedures are compared with existing heuristics, as well as with optimal solutions for the smaller instance sizes. The computational results show that the performance of the proposed genetic approach is improved by the addition of a local search procedure, as well as by the insertion of simple heuristic solutions in the initial population. Indeed, the genetic versions that include either or both of these features not only provide significantly better results, but are also much faster. The genetic versions that use local search are clearly superior to the existing heuristics, and the improvement in performance over the best existing procedure increases with both the size and difficulty of the instances. These genetic procedures are also quite close to the optimum, and provided an optimal solution for most of the test instances.
2009
Autores
Valente, JMS;
Publicação
ASIA-PACIFIC JOURNAL OF OPERATIONAL RESEARCH
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.
2009
Autores
Valente, JMS; Moreira, MRA;
Publicação
INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY
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.
2009
Autores
Branco, MC; Delgado, C;
Publicação
REVISTA ESPANOLA DE FINANCIACION Y CONTABILIDAD-SPANISH JOURNAL OF FINANCE AND ACCOUNTING
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.
2009
Autores
Rocha, C; Mendonca, T; Silva, ME;
Publicação
WISP 2009: 6TH IEEE INTERNATIONAL SYMPOSIUM ON INTELLIGENT SIGNAL PROCESSING, PROCEEDINGS
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.
The access to the final selection minute is only available to applicants.
Please check the confirmation e-mail of your application to obtain the access code.