Browsing by Issue Date, starting with "2015-07"
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- Abordagem conceitual às estratégias de Internacionalização sob pressões institucionais duais para legitimidade e conformidadePublication . Ferreira, Manuel Portugal; Serra, Fernando RibeiroInternacionalizar as operações requer que as empresas multinacionais (EMNs) desenvolvam estratégias capazes de lidar, simultaneamente, com as pressões institucionais externas, para a legitimidade, e as pressões institucionais internas, para a conformidade. Neste artigo conceitual e baseado na literatura de teoria institucional em negócios internacionais, desenvolve-se um conjunto de proposições teóricas sobre quais as estratégias de entrada nos mercados externos seguidas pelas EMNs face aos ambientes institucionais. Com foco predominante no ambiente institucional externo e nas diferenças de desenvolvimento institucional, também aborda a relevância de considerar o ambiente interno. As estratégias de entrada tendem a ser baseadas em modos de baixo envolvimento e em parcerias, como joint ventures, para entrar em países institucionalmente imaturos ou institucionalmente mais distantes. As aquisições e as parcerias podem ser usadas se as pressões institucionais forem menores. Conclui-se com uma discussão geral e o apontamento de questões para pesquisas futuras.
- Semantic Integration Framework for Resources IdentificationPublication . Pragosa, Miguel; Basto-Fernandes, Vitor; Luísa OliveiraThe global adoption of information technology systems throughout all activity domains lead to the existence of a huge amount of information systems unable to interoperate, first of all, because of different ways of identifying resources. Different transport and application level protocols for data exchange also raise some interoperability difficulties. Common interoperability scenarios rely on tightly controlled, specific communities of information technology islands. In this chapter we present and discuss the usage of lexical, syntactic and semantic lexical technologies to address interoperability problems at the product identification level, in the context of food consumption analysis.
- The efficacy of MS-222 as anaesthetic agent in four freshwater aquarium fish speciesPublication . Chambel, João; Pinho, Rúben; Sousa, Rita; Ferreira, Tânia; Baptista, Teresa; Severiano, Vera; MENDES, SUSANA; Pedrosa, RuiThe efficacy of anaesthetic tricaine methanesulfonate (MS-222) was evaluated in four freshwater aquarium fish species, Zebrafish (Danio rerio), Guppy (Poecilia reticulata), Discu (Symphysodon discus) and Green swordtail (Xiphophorus helleri). The correct dose of anaesthetic should induce the plane 4 of anaesthesia in less than 180 s, recovery in less than 300 s and must survive when exposed during 30 min to anaesthetic. Fishes were exposed to six concentrations of anaesthetic (75, 100, 125, 150, 200 and 250 mg L-1) and the time of fish reaching plane 4 of anaesthesia, post exposure recovery, and the percentage of survival when fish were subject to 30 min in the anaesthetic were recorded. The optimal doses varied according to the species: D. rerio - 75, 100 and 125 mg L-1, P. reticulata - 125, 150 and 200 mg L-1, S. discus - 75 and 100 mg L-1 and X. helleri - 125 and 150 mg L-1. The induction time generally decreased significantly with increasing concentration of MS-222 for all of the species evaluated. The recovery time had a tendency to increase with the increase of the MS-222 concentration for D. rerio, P. reticulata and S. discus. On the other hand, X. helleri recovery time decreased with the increase of MS-222 concentration. MS-222 proved to be effective in anaesthesia for all the freshwater ornamental species studied. The main results clearly show that the optimal dose to anesthetize is fish species dependent and it is completely wrong to extrapolate optimal anaesthetic concentrations between different species.
- Intra Predictive Depth Map Coding Using Flexible Block PartitioningPublication . Lucas, Luis F. R.; Wegner, Krzysztof; M. M. Rodrigues, Nuno; Pagliari, Carla L.; Silva, Eduardo A. B. da; Faria, SergioA complete encoding solution for efficient intra-based depth map compression is proposed in this paper. The algorithm, denominated predictive depth coding (PDC), was specifically developed to efficiently represent the characteristics of depth maps, mostly composed by smooth areas delimited by sharp edges. At its core, PDC involves a directional intra prediction framework and a straightforward residue coding method, combined with an optimized flexible block partitioning scheme. In order to improve the algorithm in the presence of depth edges that cannot be efficiently predicted by the directional modes, a constrained depth modeling mode, based on explicit edge representation, was developed. For residue coding, a simple and low complexity approach was investigated, using constant and linear residue modeling, depending on the prediction mode. The performance of the proposed intra depth map coding approach was evaluated based on the quality of the synthesized views using the encoded depth maps and original texture views. The experimental tests based on all intra configuration demonstrated the superior rate-distortion performance of PDC, with average bitrate savings of 6%, when compared with the current state-of-the-art intra depth map coding solution present in the 3D extension of a high-efficiency video coding (3D-HEVC) standard. By using view synthesis optimization in both PDC and 3D-HEVC encoders, the average bitrate savings increase to 14.3%. This suggests that the proposed method, without using transform-based residue coding, is an efficient alternative to the current 3D-HEVC algorithm for intra depth map coding.
- Known Mean, Unknown Maxima? Testing the Maximum Knowing Only the MeanPublication . Santos, Rui; Oliveira Martins, João Paulo; Felgueiras, MiguelIn the quantitative group testing problem, the use of the group mean to identify if the group maximum is greater than a prefixed threshold (infected group) is analyzed, using n independent and identically distributed individuals. Under these conditions, it is shown that the information of the mean is sufficient to classify each group as infected or healthy with low probability of misclassification when the underline distribution is a unilateral heavy-tailed distribution.
- Improving Organizational Effectiveness with Enterprise Information SystemsPublication . Varajão, João Eduardo; Cruz-Cunha, Maria Manuela; Martinho, Ricardo; Varajão, João Eduardo; Cruz-Cunha, Maria Manuela; Martinho, RicardoInformation and communication technologies are widely used to improve organizational efficiency and ensure effective workflows. Technology and software systems provide the opportunity to improve productivity and efficiency when used correctly; however, professionals continue to encounter challenges in a variety of settings.Improving Organizational Effectiveness with Enterprise Information Systems analyzes the challenges and solutions associated with integrating new technologies in organizations, including key topics in cloud computing, project management, and operational procedure development and implementation. This publication is an essential reference source for senior managers, CIOs, ICT professionals, project managers, researchers, academicians, and upper level students interested in the applications and advances in ICTs and IS.
- Text Mining Applied to Electronic Medical RecordsPublication . Pereira, Luis; Rijo, Rui, Rui Pedro Charters Lopes; Silva, Catarina; Martinho, RicardoThe analysis of medical records is a major challenge, considering they are generally presented in plain text, have a very specific technical vocabulary and are nearly always unstructured. It is an interdisciplinary work that requires knowledge from several fields. The analysis may have several goals, such as assistance on clinical decision, classification of medical procedures, and to support hospital management decisions. This work presents the concepts involved, the relevant existent related work, and the main open issues for future research within the analysis of electronic medical records, using data and text mining techniques. It provides a comprehensive contextualization to all those who wish to perform an analytical work of medical records, enabling the identification of fruitful research fields. With the digitalization of medical records and the large amount of medical data available, this is an area of wide research potential.
- Quality evaluation of depth map error concealment using a perceptually-aware objective metricPublication . Marcelino, S.; Faria, S.; Pepion, R.; Le Callet, P.; Soares, S.; Assunção, P.This paper presents a quality evaluation study on the performance of error concealment methods for depth maps used in multiview video-plus-depth (MVD). The research deals with the problem of decoding corrupted depth maps received from error-prone networks, where the quality of the reconstructed depth data is not always directly related to the quality of the virtual views synthesised by those maps. Even after error concealment such distortions are not particularly perceived as other known types, such as coding distortion. Thus, traditional quality metrics are not adequate to capture all the relevant features. In this work, the performance of two error concealment methods for depth maps is evaluated using a perceptually-aware objective metric. This metric is validated through subjective assessment of virtual views synthesised with concealed depth maps. Each subjective test is performed by comparing the relative quality between between two synthesised images using different error concealment methods. The perceptual impact of reconstruction in corrupted depth of MVD is evaluated under various loss rates, using several colour images and depth maps encoded at multiple quantisation steps. The achieved results reveal that the proposed objective quality metric is mostly inline with user preferences, in respect to the relative performance of each error concealment method.
- Encoding time control system for HEVC based on Rate-Distortion-Complexity analysisPublication . Correa, Guilherme; Assunção, Pedro; Cruz, Luis A. da Silva; Agostini, LucianoThe improved compression efficiency of High Efficiency Video Coding (HEVC) comes with large increases in computational complexity, which has been lately dealt by researchers with complexity reduction and scaling methods. However, encoding time control at frame or Group of Pictures (GOP) level is still an open issue that must be investigated. In this work, a Rate-Distortion-Complexity analysis is performed upon a set of configurations that have been created based on findings and techniques of previous works. The proposed control system uses the best 27 configurations to adjust the encoding time per GOP and yields encoding time reductions of up to 84.5% with an average difference between target and encoding times of 4.1%. © 2015 IEEE.
- Open Source para a Administração Pública: J2Gov - Joomla to governmentPublication . Martins, Pedro Matos; Pereira, AntónioThis project is the development of a component for the Content Management System Joomla, titled J2Gov (Joomla to government), which can cater for the requirements of public administration bodies, which relate directly to the public. In a single platform, a tool to provide an interface for online services, presential services, document management and control and measurement times and performances. In this context, this project was developed as a way to meet the needs of public administration, regardless of their size, financial capacity or technical expertise of its human resources in the field of information technology.