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Publications

2011

An Integer Programming Model for the Management of a Forest in the North of Portugal

Authors
Cerveira, A; Fonseca, T; Mota, A; Martins, I; Simos, TE; Psihoyios, G; Tsitouras, C; Anastassi, Z;

Publication
NUMERICAL ANALYSIS AND APPLIED MATHEMATICS ICNAAM 2011: INTERNATIONAL CONFERENCE ON NUMERICAL ANALYSIS AND APPLIED MATHEMATICS, VOLS A-C

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.

2011

Short-term wind power forecasting using a hybrid evolutionary intelligent approach

Authors
Catalao, JPS; Osorio, GJ; Pousinho, HMI;

Publication
2011 16th International Conference on Intelligent System Applications to Power Systems, ISAP 2011

Abstract
This paper presents a hybrid evolutionary intelligent approach, based on a combination of evolutionary particle swarm optimization (EPSO) with an adaptive-network-based fuzzy inference system (ANFIS), for short-term wind power forecasting in Portugal. The increased integration of wind power into the electric grid, as nowadays occurs in Portugal, poses challenges due to its intermittency and volatility. Hence, good forecasting tools are important for tackling these challenges. The accuracy of the wind power forecasting attained with the proposed approach is evaluated, reporting the numerical results from a real-world case study. © 2011 IEEE.

2011

Protective effect of physical activity on dissatisfaction with body image in children - A cross-sectional study

Authors
Monteiro Gaspar, MJM; Amaral, TF; Oliveira, BMPM; Borges, N;

Publication
PSYCHOLOGY OF SPORT AND EXERCISE

Abstract
Objective: To evaluate, in pre-adolescents and adolescents, the frequency of body image dissatisfaction and distortion and to assess the association between these factors and physical activity and body mass index (BMI). Design: Cross-sectional study. Methods: 234 children (10-17 years) from a Porto high school were evaluated. Dissatisfaction with body image (FID) was assessed by Collins' child figure drawings for pre-adolescents and adolescents. FID was calculated as the discrepancy between the "ideal figure" and the "perceived figure". Body image distortion (BID) was calculated as the discrepancy between the "perceived figure" and the "real figure". The Baecke questionnaire was applied to determine the habitual physical activity index (HPAI) of each participant. Results: Girls were more dissatisfied than boys with their body image (68.1% vs 52.9%). A high proportion of students of both genders and age groups revealed BID (71.8%) with 51.3% underestimating their body image and 20.5% overestimating it. A negative association was found between the FID and BID (girls: r = -.259, p = .006: boys: r = -.414, p < .001). High levels of physical activity were associated with a protective effect on FID, OR = 0.38, 95% CI [0.16, 0.87] for 3rd vs 1st quartile of HPAI: OR = 0.29, 95% CI [0.12, 0.86], for 4th vs 1st quartile of HPAI, both adjusted for BMI and gender, but HPAI was not associated with BID. Conclusion: FID and BID are highly frequent and inversely associated. BID increases directly with BMI percentiles in both genders while physical activity has a protective effect on dissatisfaction of body image.

2011

An Exploratory Study on the Impact of Temporal Features on the Classification and Clustering of Future-Related Web Documents

Authors
Campos, R; Dias, G; Jorge, A;

Publication
PROGRESS IN ARTIFICIAL INTELLIGENCE

Abstract
In the last few years, a huge amount of temporal written information has become widely available on the Internet with the advent of forums, blogs and social networks. This gave rise to a new challenging problem called future retrieval, which consists of extracting future temporal information, that is known in advance, from web sources in order to answer queries that combine text of a future temporal nature. This paper aims to confirm whether web snippets can be used to form an intelligent web that can detect future expected events when their dates are already known. Moreover, the objective is to identify the nature of future texts and understand how these temporal features affect the classification and clustering of the different types of future-related texts: informative texts, scheduled texts and rumor texts. We have conducted a set of comprehensive experiments and the results show that web documents are a valuable source of future data that can be particularly useful in identifying and understanding the future temporal nature of a given implicit temporal query.

2011

Media Ecosystems: A Novel Approach for Content-Awareness in Future Networks

Authors
Koumaras, H; Négru, D; Borcoci, E; Koumaras, V; Troulos, C; Lapid, Y; Pallis, E; Sidibé, M; Pinto, A; Gardikis, G; Xilouris, G; Timmerer, C;

Publication
The Future Internet - Future Internet Assembly 2011: Achievements and Technological Promises

Abstract
This chapter proposes a novel concept towards the deployment of a networked 'Media Ecosystem'. The proposed solution is based on a flexible cooperation between providers, operators, and end-users, finally enabling every user first to access the offered multimedia services in various contexts, and second to share and deliver his own audiovisual content dynamically, seamlessly, and transparently to other users. Towards this goal, the proposed concept provides content-awareness to the network environment, network- and user context-awareness to the service environment, and adapted services/content to the end user for his best service experience possible, taking the role of a consumer and/or producer. © 2011 Springer-Verlag Berlin Heidelberg.

2011

Metabolic syndrome, adipokines and ghrelin in overweight and obese schoolchildren: results of a 1-year lifestyle intervention programme

Authors
Pedrosa, C; Oliveira, BMPM; Albuquerque, I; Simoes Pereira, C; Vaz de Almeida, M; Correia, F;

Publication
EUROPEAN JOURNAL OF PEDIATRICS

Abstract
The aim of this study was to evaluate the effect of a lifestyle intervention programme (nutrition and exercise counselling) on metabolic syndrome (MS) components, adipokines (leptin, adiponectin) and ghrelin levels in overweight children. A total of 61 overweight children aged 7-9 years (>= 85th body mass index (BMI) percentile; 27 boys/34 girls) were randomly assigned and completed a 1-year individual (IT) or group-based treatment (GT). Anthropometric and biochemical parameters were assessed at baseline, at 6 months and at 1 year. Twenty-two normal weight children (< 85th BMI percentile; 7-9 years old; 13 boys/nine girls) were also evaluated at baseline. Insulin resistance (IR) was determined by the homeostasis model assessment of IR (HOMA-IR). Overweight children presented significantly higher blood pressure, triglycerides, apolipoprotein B, insulin, HOMA-IR, leptin, C-reactive protein and homocysteine levels, while apolipoprotein A-I was significantly lower. At baseline, MS was present in ten overweight children, of which only five maintained it at 1 year. Leptin and ghrelin levels were associated with IR and MS components. MS was predicted by apolipoprotein A-I, insulin and pre-puberty. The lifestyle intervention led to a significant improvement in standard deviation score of BMI, waist circumference/height ratio and lipid profile. Changes in insulin, HOMA-IR, leptin and adiponectin were not significant. Ghrelin behaved differently between IT and GT. The GT intervention seems to be more successful, with a decrease in BMI Z-score and an improvement of metabolic parameters. In conclusion, overweight children have multiple risk factors associated with MS. A lifestyle intervention programme seems to be an effective mean for reducing obesity and MS components and improving adipokines concentrations.

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