Segmentation-based video coding:temporals links

This paper analyzes the main elements that a segmentation-based video coding approach should be based on so that it can address coding efficiency and content-based functionalities. Such elements can be defined as temporal linking and rate control. The basic features of such elements are discussed and, in both cases, a specific implementation is proposed.Peer ReviewedPostprint (published version

A segmentation-based coding system allowing manipulation of objects (sesame)

We present a coding scheme that achieves, for each image in the sequence, the best segmentation in terms of rate-distortion theory. It is obtained from a set of initial regions and a set of available coding techniques. The segmentation combines spatial and motion criteria. It selects at each area of the image the most adequate criterion for defining a partition in order to obtain the best compromise between cost and quality. In addition, the proposed scheme is very suitable for addressing content-based functionalities.Peer ReviewedPostprint (published version

Evaluation Strategies for Datalog-based Points-To Analysis

During the last decade, several hard problems have been described and solved in Datalog in a sound way (points-to analyses, data web management, security, privacy, and trust). In this work, we describe novel evaluation strategies for this language within the context of program analyses. We first decompose any Datalog program into a program where rules have at most two atoms in their body. Then, we show that a specialized bottom-up evaluation algorithm with time and memory guarantees can be described as the on-the-fly resolution of a Boolean Equation System (Bes). The resolution computes all ground atoms in an efficient way thanks to a compact data structure with constant time access that has so far not been used in the Datalog or the Bes literature. A prototype has been developed and tested on a number of real Java projects in the context of Andersen’s points-to analysis. Experimental results show that our prototype is better than state-of-the-art solvers in terms of resolution time and memory consumption

Chatbot para atendimento automatizado

A área da inteligência artificial vem evoluindo muito rapidamente junto com as tecnologias computacionais. O desenvolvimento de máquinas capazes de realizar tarefas, que até então eram exclusivamente humanas, como atendimento de clientes, por exemplo, tem se tornado cada vez mais comum. Deste modo o chatbot é uma tecnologia que vem revolucionando a maneira que as empresas estão prestando seus serviços, permitindo a redução de custos com pessoal, padronização das informações e uma melhor experiencia com o seu usuário final. Entre as diversas aplicações está o atendimento ao cliente, onde o mesmo pode obter informações, esclarecer dúvidas e até mesmo realizar operações de maneira autónoma, prática e com alta qualidade. O presente trabalho apresenta um estudo e desenvolvimento de um chatbot como mais uma alternativa ao atendimento padrão já realizado hoje dentro de uma central de atendimento

Natural disasters, remote sensing, and synthetic controls

Satellite imagery has been used for decades to study changes on Earth’s surface and understand the mechanisms that have shaped it as we know it today. Moreover, substantial improvements in computing power and the increase of data available in recent years have boosted interest for this kind of research. Pixel-based composites of large areas are easily accessible today thanks to the Google Earth Engine platform[1]. These are being used to study the evolution of different ecosystems such as forests[2], as well as the frequency of wildfires. Furthermore, technological advances over the last decades have enabled to precisely monitor variations in extreme weather events[3]. These weather phenomena seem to be larger now in quantity and size due to the increase of climate volatility[4]. The consequences of natural hazards have been mostly studied by comparing pre- and post-disaster conditions, or simple pair-wise comparisons between affected and non-affected areas, rendering inaccurate estimates[5]. We are interested in developing a system that, by means of a synthetic control approach, will enable us to causally evaluate the effects of disturbances over areas of interest using satellite imagery. Resilience is another field of interest for the research community. The decrease in resilience of regions that are recurrently hit by these events might end up making certain places inhabitable. For example, extreme weather events already have their toll on life expectancy in the US[6]. Hence, large migrations may follow as a result in the long term

Sistema de gestão de atividades docentes de supervisão

O presente relatório descreve um protótipo para o apoio à gestão da informação associada com a atividade de supervisão realizada no âmbito do ensino superior. São apresentados os requisitos e os diagramas associados com o sistema. Adicionalmente, a arquitetura, diagrama de classes e os ecrans principais do protótipo são descritos.info:eu-repo/semantics/publishedVersio

Measuring Spatial Subdivisions in Urban Mobility with Mobile Phone Data

Urban population grows constantly. By 2050 two thirds of the world population will reside in urban areas. This growth is faster and more complex than the ability of cities to measure and plan for their sustainability. To understand what makes a city inclusive for all, we define a methodology to identify and characterize spatial subdivisions: areas with over- and under-representation of specific population groups, named hot and cold spots respectively. Using aggregated mobile phone data, we apply this methodology to the city of Barcelona to assess the mobility of three groups of people: women, elders, and tourists. We find that, within the three groups, cold spots have a lower diversity of amenities and services than hot spots. Also, cold spots of women and tourists tend to have lower population income. These insights apply to the floating population of Barcelona, thus augmenting the scope of how inclusiveness can be analyzed in the city.Comment: 10 pages, 10 figures. To be presented at the Data Science for Social Good workshop at The Web Conference 202

Requirements Management and Acquisition Management experiences in Spanish Public Administrations

As a part of the activities of the first Symposium on Process Improvement Models and Software Quality of the Spanish Public Administration, working groups were formed to discuss the current state of the Requirements Management and Supplier Agreement Management processes. This article presents general results and main contributions of those working groups. The results have allowed the obtention of a preliminary appraisal of the current state of these two processes in the Spanish Public Administration

Novedades para la flora de Manzanera y su entorno (Sierra de Javalambre, Teruel)

Data are offered and commented on 14 taxa of new or little known vascular plants for the Sierra de Javalambre, province of Teruel, more specifically in the municipal boundaries of Manzanera and Riodeva. The contributions of Epipactis provincialis Aubenas & Robatsch for the first and Primula acaulis (L.) Hill for the second one stand out