Dinámica de los predictores de adopción de Internet en Medellín

En este trabajo se propone analizar la dinámica del impacto asociado a algunos predictores de la adopción de internet en la ciudad de Medellín (Colombia), utilizando como base de datos la Encuesta de calidad de vida de Medellín (ECV) desde el año 2006 a 2014 -- Se analizarán que variables inciden en la tenencia de internet, se realizará la estadística descriptiva necesaria, y regresiones mediante los modelos Logit y Probit -- El acceso a internet aún se encuentra reservado para una parte privilegiada de la población que cuenta con suficiente ingreso para tener servicio en casa y computador -- Se evidenció igualmente que en la ciudad no hay presencia de brecha de género contrario a lo encontrado en la literatura

Teaching Through Technology – the Experience of Bulgarian Teachers

Report published in the Proceedings of the National Conference on "Education and Research in the Information Society", Plovdiv, May, 2016

Guidelines for Creating ICT-based Adaptable Learning Resources

Report published in the Proceedings of the National Conference on "Education and Research in the Information Society", Plovdiv, May, 2014

Tighter, Neater, Safer C and C++

Report published in the Proceedings of the National Conference on "Education and Research in the Information Society", Plovdiv, May, 2016

Humanidades digitales y la escuela 2.0

During the last decades the growth and development of Information and Communication Technologies (ICT) have led us to a new social paradigm that reflects a deep change not only in an individual but also in a social behavioural pattern. All these changes define the so-called knowledge and information society. This social evolution has had different textual states and types as its main core and instrument of transformation therefore scholars and specialists in the field of Humanities have not missed the opportunity of studying recent phenomena, which have come from the current setting given by new technologies. Researchers in Humanities have had to reconsider their own traditional working method based on printed text in order to analyse how nowadays we search for data, select them, analyse them and the ways we create and spread new information and knowledge. Having in mind this scenario where humanist works, the concept of Digital Humanities has arisen conditioned by the existence of cyberspace, digital text, hypertext, on-line text, implementation of new ways of communication, global access to information and various elements which build a common methodology for all humanistic disciplines. Most of these changes have affected the educational system and education as an academic and humanistic discipline.

O impacto das Bibliotecas Escolares na promoção dos Hábitos de Leitura

Dada a importância que é atribuída à leitura, entendida como ferramenta essencial para a plena inserção dos cidadãos na sociedade, a luta pela melhoria dos níveis de leitura e literacia da população portuguesa tornou-se um desígnio nacional bastante enfatizado nas últimas décadas. Vários estudos sobre hábitos de leitura efectuados na década de 80/90, quer a nível nacional quer internacional, vieram pôr a descoberto as fragilidades de Portugal e o seu atraso em relação aos restantes países da Europa. Os portugueses não revelavam as competências necessárias para ter sucesso na sociedade da informação. O sistema educativo tem um papel chave na mudança que é urgente operar, residindo os alicerces dessa mudança na promoção da leitura e da literacia. É neste contexto que surge a criação da Rede de Bibliotecas Escolares, lançada em 1996, como medida conjunta do Ministério da Educação e da Cultura, com vista a criar condições para que os portugueses pudessem alcançar níveis de leitura mais favoráveis e mais próximos dos restantes países europeus. A promoção da leitura passa a ser uma área de intervenção prioritária das bibliotecas escolares em Portugal. Face aos baixos níveis de literacia dos alunos portugueses, revelados pelo PISA 2000, o governo dá continuidade às suas políticas de promoção da leitura e da literacia. No ano de 2007 é apresentado o Plano Nacional de Leitura (PNL), fazendo-se o apelo à mobilização de todos como condição essencial para a sua eficácia - elevar os níveis de literacia dos portugueses. É importante dar nota que o PNL e as Bibliotecas Escolares estão fortemente conectados, funcionando estas como os “alicerces” que suportam o desenvolvimento dos projectos do PNL. Os resultados desta “parceria” e de todas as iniciativas com vista à promoção da leitura e da literacia têm-se revelado bastante profícuos, e a prová-lo estão os resultados do PISA 2009. Tendo os anos de 2000 e 2009 como domínio de referência a leitura, constatou-se que nesse período de tempo houve uma clara melhoria dos níveis de literacia dos portugueses. Não obstante uma ligeira descida verificada nos resultados do ano de 2012, a OCDE sublinhou as melhorias que o país obteve desde que começou a ser avaliado. No entanto, julgamos pertinente dar nota que, para além desta evolução se ter verificado não apenas em Portugal, há países que evoluíram de forma muito mais acelerada, encontrando-se numa posição mais favorável que Portugal (25º posição), no ranking dos países da OCDE. Com o estudo que aqui apresentamos, baseado na análise de um universo de 8 bibliotecas escolares do concelho de Felgueiras, pretendemos conhecer a realidade destas bibliotecas dentro do contexto nacional. Foi nosso objetivo verificar se cumprem o seu papel na promoção dos hábitos de leitura e da literacia, de que forma o fazem, e as dificuldades concretas com que se deparam. As conclusões apontam-nos para uma realidade que não difere muito da realidade das restantes bibliotecas do país, das quais temos conhecimento. Os professores bibliotecários cumprem o seu papel na promoção dos hábitos de leitura, deparando-se com a falta de apoio de meios humanos, aspecto que se tem agravado de forma preocupante nos últimos anos. A conjuntura atual de desinvestimento nos serviços públicos, não poderia deixar de se fazer sentir. Constatamos no entanto que, apesar das adversidades, as BEs não se reduzem a meros centros de recursos e a locais de lazer para quem as queira visitar. Têm um papel ativo, tomam incitativas diversas de promoção da leitura / literacia, nos moldes definidos pelo MABE, com estímulo à leitura autónoma. Procuram articular as suas acções com os docentes e, em simultâneo, vencer a relativa indiferença e desinteresse destes pela biblioteca, motivando-os para as suas actividades e procurando levá-los a ver na BE um parceiro ativo, capaz de os apoiar na concretização dos programas curriculares e na análise de resultados escolares dos alunos como base para delinear estratégias pedagógicas comuns. Por fim, constatamos que apesar de as BEs procurarem integrar nas suas atividades a comunidade exterior à escola, a adesão, sobretudo das famílias, tem sido débil: os encarregados de educação aderem relativamente bem ao papel de público passivo, mas não assumem o papel de interlocutores ativos, como se pretende. Estas conclusões, ousamos dizer, remetem-nos para a necessidade urgente de uma reflexão séria por parte do Estado Português, em relação à Educação e às suas prioridades.

URIs and Intertextuality: Incumbent Philosophical Commitments in the Development of the Semantic Web

Examines two commitments inherent in Resource Description Framework (RDF): intertextuality and rationalism. After introducing how rationalism has been studied in knowledge organization, this paper then introduces the concept of bracketed-rationalism. This paper closes with a discussion of ramifications of intertextuality and bracketed rationalism on evaluation of RDF.

"Dime qué te enseñan y te diré en lo que crees": conceptualizaciones y percepciones estudiantiles sobre la democracia a partir de las experiencias suscitadas por las prácticas de formación democrática adelantadas en un colegio público de Bogotá.

La década de los años 90 fue un periodo de grandes transformaciones a nivel económico, social y político en Colombia. Una de las transformaciones más significativas en el ámbito educativo tuvo que ver con la introducción en la escuela de una serie de prácticas destinadas a garantizar la formación democrática de los ciudadanos; todo esto con el propósito de consolidar en la sociedad una serie de hábitos, valores y prácticas acordes con el nuevo orden social instaurado y amparado por la Constitución Política de 1991. Pese a los esfuerzos legislativos y estatales por promover la democracia en el entorno escolar, las prácticas adelantadas en las instituciones educativas no han logrado responder efectivamente al objetivo de consolidar un ambiente democrático en la escuela y en la sociedad en general, razón por la cual, en este trabajo se realiza un análisis de la manera como una institución educativa en particular, asume y pone en marcha las propuestas democráticas formuladas legalmente, las tensiones suscitadas por la introducción de la propuesta democrática en la escuela, además de las conceptualizaciones sobre la democracia que dichas prácticas contribuyen a configurar y las cuales dan forma a los imaginarios, acciones y discursos cotidianos de estudiantes y docentes específicamente.

Changing the paradigm: endoscopic video analysis and information extraction for safer surgeries

Background: Minimally invasive surgery creates two technological opportunities: (1) the development of better training and objective evaluation environments, and (2) the creation of image guided surgical systems.

Compression Efficiency Analysis of Wyner-Ziv Video Coding with Motion Compensated Side Information Interpolation

The Wyner-Ziv video coding (WZVC) rate distortion performance is highly dependent on the quality of the side information, an estimation of the original frame, created at the decoder. This paper, characterizes the WZVC efficiency when motion compensated frame interpolation (MCFI) techniques are used to generate the side information, a difficult problem in WZVC especially because the decoder only has available some reference decoded frames. The proposed WZVC compression efficiency rate model relates the power spectral of the estimation error to the accuracy of the MCFI motion field. Then, some interesting conclusions may be derived related to the impact of the motion field smoothness and the correlation to the true motion trajectories on the compression performance.

A flexible side information generation framework for distributed video coding

One of the most efficient approaches to generate the side information (SI) in distributed video codecs is through motion compensated frame interpolation where the current frame is estimated based on past and future reference frames. However, this approach leads to significant spatial and temporal variations in the correlation noise between the source at the encoder and the SI at the decoder. In such scenario, it would be useful to design an architecture where the SI can be more robustly generated at the block level, avoiding the creation of SI frame regions with lower correlation, largely responsible for some coding efficiency losses. In this paper, a flexible framework to generate SI at the block level in two modes is presented: while the first mode corresponds to a motion compensated interpolation (MCI) technique, the second mode corresponds to a motion compensated quality enhancement (MCQE) technique where a low quality Intra block sent by the encoder is used to generate the SI by doing motion estimation with the help of the reference frames. The novel MCQE mode can be overall advantageous from the rate-distortion point of view, even if some rate has to be invested in the low quality Intra coding blocks, for blocks where the MCI produces SI with lower correlation. The overall solution is evaluated in terms of RD performance with improvements up to 2 dB, especially for high motion video sequences and long Group of Pictures (GOP) sizes.

Advanced side information creation techniques and framework for Wyner-Ziv video coding

Recently, several distributed video coding (DVC) solutions based on the distributed source coding (DSC) paradigm have appeared in the literature. Wyner-Ziv (WZ) video coding, a particular case of DVC where side information is made available at the decoder, enable to achieve a flexible distribution of the computational complexity between the encoder and decoder, promising to fulfill novel requirements from applications such as video surveillance, sensor networks and mobile camera phones. The quality of the side information at the decoder has a critical role in determining the WZ video coding rate-distortion (RD) performance, notably to raise it to a level as close as possible to the RD performance of standard predictive video coding schemes. Towards this target, efficient motion search algorithms for powerful frame interpolation are much needed at the decoder. In this paper, the RD performance of a Wyner-Ziv video codec is improved by using novel, advanced motion compensated frame interpolation techniques to generate the side information. The development of these type of side information estimators is a difficult problem in WZ video coding, especially because the decoder only has available some reference, decoded frames. Based on the regularization of the motion field, novel side information creation techniques are proposed in this paper along with a new frame interpolation framework able to generate higher quality side information at the decoder. To illustrate the RD performance improvements, this novel side information creation framework has been integrated in a transform domain turbo coding based Wyner-Ziv video codec. Experimental results show that the novel side information creation solution leads to better RD performance than available state-of-the-art side information estimators, with improvements up to 2 dB: moreover, it allows outperforming H.264/AVC Intra by up to 3 dB with a lower encoding complexity.

Augmented LDPC Graph for Distributed Video Coding with Multiple Side Information

The advances made in channel-capacity codes, such as turbo codes and low-density parity-check (LDPC) codes, have played a major role in the emerging distributed source coding paradigm. LDPC codes can be easily adapted to new source coding strategies due to their natural representation as bipartite graphs and the use of quasi-optimal decoding algorithms, such as belief propagation. This paper tackles a relevant scenario in distributedvideo coding: lossy source coding when multiple side information (SI) hypotheses are available at the decoder, each one correlated with the source according to different correlation noise channels. Thus, it is proposed to exploit multiple SI hypotheses through an efficient joint decoding technique withmultiple LDPC syndrome decoders that exchange information to obtain coding efficiency improvements. At the decoder side, the multiple SI hypotheses are created with motion compensated frame interpolation and fused together in a novel iterative LDPC based Slepian-Wolf decoding algorithm. With the creation of multiple SI hypotheses and the proposed decoding algorithm, bitrate savings up to 8.0% are obtained for similar decoded quality.

Side information creation for efficient Wyner-Ziv video coding: Classifying and reviewing

Video coding technologies have played a major role in the explosion of large market digital video applications and services. In this context, the very popular MPEG-x and H-26x video coding standards adopted a predictive coding paradigm, where complex encoders exploit the data redundancy and irrelevancy to 'control' much simpler decoders. This codec paradigm fits well applications and services such as digital television and video storage where the decoder complexity is critical, but does not match well the requirements of emerging applications such as visual sensor networks where the encoder complexity is more critical. The Slepian Wolf and Wyner-Ziv theorems brought the possibility to develop the so-called Wyner-Ziv video codecs, following a different coding paradigm where it is the task of the decoder, and not anymore of the encoder, to (fully or partly) exploit the video redundancy. Theoretically, Wyner-Ziv video coding does not incur in any compression performance penalty regarding the more traditional predictive coding paradigm (at least for certain conditions). In the context of Wyner-Ziv video codecs, the so-called side information, which is a decoder estimate of the original frame to code, plays a critical role in the overall compression performance. For this reason, much research effort has been invested in the past decade to develop increasingly more efficient side information creation methods. This paper has the main objective to review and evaluate the available side information methods after proposing a classification taxonomy to guide this review, allowing to achieve more solid conclusions and better identify the next relevant research challenges. After classifying the side information creation methods into four classes, notably guess, try, hint and learn, the review of the most important techniques in each class and the evaluation of some of them leads to the important conclusion that the side information creation methods provide better rate-distortion (RD) performance depending on the amount of temporal correlation in each video sequence. It became also clear that the best available Wyner-Ziv video coding solutions are almost systematically based on the learn approach. The best solutions are already able to systematically outperform the H.264/AVC Intra, and also the H.264/AVC zero-motion standard solutions for specific types of content. (C) 2013 Elsevier B.V. All rights reserved.

A denoising approach for iterative side information creation in distributed video coding

In distributed video coding, motion estimation is typically performed at the decoder to generate the side information, increasing the decoder complexity while providing low complexity encoding in comparison with predictive video coding. Motion estimation can be performed once to create the side information or several times to refine the side information quality along the decoding process. In this paper, motion estimation is performed at the decoder side to generate multiple side information hypotheses which are adaptively and dynamically combined, whenever additional decoded information is available. The proposed iterative side information creation algorithm is inspired in video denoising filters and requires some statistics of the virtual channel between each side information hypothesis and the original data. With the proposed denoising algorithm for side information creation, a RD performance gain up to 1.2 dB is obtained for the same bitrate.