Articles

Evaluation of linear relaxations in Ad Network optimization for online marketing

Ad Networks connect advertisers to websites that want to host advertisements. When users request websites, the Ad Network decides which ad to send so as to maximize the number of ads that are clicked by users....

Authors: Valdinei Freire, Flávio Sales Truzzi, Anna Helena Reali Costa and Fabio Gagliardi Cozman

An inter-FPGA communication bus with error detection and dynamic clock phase adjustment

Nowadays, systems involving multiple FPGAs are used for various scientific applications. Such systems require a data bus dedicated to the communication between FPGAs, which could be done through a LVDS type. A...

Authors: LT Melo, SHC Santana, AG Silva-Filho, ME Lima, VWC Medeiros and MLM Marinho

Generalized probabilistic satisfiability through integer programming

This paper studies the generalized probabilistic satisfiability (GPSAT) problem, where the probabilistic satisfiability (PSAT) problem is extended by allowing Boolean combinations of probabilistic assertions a...

Authors: Glauber De Bona, Fabio G. Cozman and Marcelo Finger

Evaluation of cutoff policies for term extraction

This paper presents a policy to choose cutoff points to identify potentially relevant terms in a given domain. Term extraction methods usually generate term lists ordered according to a relevance criteria, and...

Authors: Lucelene Lopes and Renata Vieira

Searching contexts in paraconsistent rough description logic

Query refinement is an interactive process of query modification used to increase or decrease the scope of search results in databases or ontologies.

Authors: Henrique Viana, João Alcântara and Ana Teresa Martins

Performance evaluation of single- and multi-hop wireless networks-on-chip with NAS Parallel Benchmarks

Parallel processing in the era of many-core processors demands high-performance networks-on-chip and parallel communication based on intra-chip message passing. In this context, wireless networks-on-chip (WiNo...

Authors: Amanda M.P. Amorim, Poliana A.C. Oliveira and Henrique C. Freitas

Reachability-based model reduction for Markov decision process

This paper presents how to improve model reduction for Markov decision process (MDP), a technique that generates equivalent MDPs that can be smaller than the original MDP. In order to improve the current state...

Authors: Felipe M Santos, Leliane N Barros and Felipe W Trevizan

Open information extraction based on lexical semantics

Open Information Extraction (Open IE) aims to obtain not predefined, domain-independent relations from text. This article introduces the Open IE research field, thoroughly discussing the main ideas and systems...

Authors: Clarissa Castellã Xavier, Vera Lúcia Strube de Lima and Marlo Souza

ApproxMap - a method for mapping blank nodes in RDF datasets

Versioning has proven to be essential in areas like software development or data and knowledge management. For systems or applications making use of documents formatted according to the Resource Description Fr...

Authors: Juliano de Almeida Monte-Mor and Adilson Marques da Cunha

Evaluating word embeddings and a revised corpus for part-of-speech tagging in Portuguese

Part-of-speech tagging is an important preprocessing step in many natural language processing applications. Despite much work already carried out in this field, there is still room for improvement, especially ...

Authors: Erick R Fonseca, João Luís G Rosa and Sandra Maria Aluísio

An open-source rule-based syllabification tool for Brazilian Portuguese

The automatic syllabification process is an essential prerequisite for speech synthesis systems. However, the task is not trivial, and several techniques have been adopted over the last decade. Furthermore, wh...

Authors: Nelson Neto, Willian Rocha and Gleidson Sousa

On the parallel efficiency and scalability of the correntropy coefficient for image analysis

Similarity measures have application in many scenarios of digital image processing. The correntropy is a robust and relatively new similarity measure that recently has been employed in various engineering appl...

Authors: Aluisio I Rêgo Fontes, Samuel Xavier-de-Souza, Adrião D Dória Neto and Luiz Felipe de Queiroz Silveira

Optimizing metric access methods for querying and mining complex data types

There are several application scenarios that can take advantage from the efficient processing of similarity operations in complex data types, such as multimedia data. Among them, it is possible to mention the ...

Authors: Jessica Andressa de Souza, Humberto Luiz Razente and Maria Camila N Barioni

Chordal- (k,ℓ)and strongly chordal- (k,ℓ)graph sandwich problems

In this work, we consider the graph sandwich decision problem for property Π, introduced by Golumbic, Kaplan and Shamir: given two graphs G¹=(V,E¹) and G²=(V,E²), the question is to know whether there exists a gr...

Authors: Fernanda Couto, Luerbio Faria and Sulamita Klein

Ranking MEDLINE documents

BioTextRetriever is a Web-based search tool for retrieving relevant literature in Molecular Biology and related domains from MEDLINE. The core of BioTextRetriever is the dynamic construction of a classifier ca...

Authors: Célia Talma Gonçalves, Rui Camacho and Eugénio Oliveira

Network-based data classification: combining K-associated optimal graphs and high-level prediction

Traditional data classification techniques usually divide the data space into sub-spaces, each representing a class. Such a division is carried out considering only physical attributes of the training data (e....

Authors: Murillo G Carneiro, João LG Rosa, Alneu A Lopes and Liang Zhao

A survey of automatic term extraction for Brazilian Portuguese

Term extraction is highly relevant as it is the basis for several tasks, such as the building of dictionaries, taxonomies, and ontologies, as well as the translation and organization of text data.

Authors: Merley da Silva Conrado, Ariani Di Felippo, Thiago Alexandre Salgueiro Pardo and Solange Oliveira Rezende

An agent-based approach for road pricing: system-level performance and implications for drivers

Road pricing is a useful mechanism to align private utility of drivers with a system-level measure of performance. Traffic simulation can be used to predict the impact of road pricing policies. The simulation ...

Authors: Anderson Rocha Tavares and Ana LC Bazzan

The life cycle of a customized communication device for a child with cerebral palsy: contributions toward the PD4CAT method

In this paper, we report the results of an action research conducted to design a communication device to help a non-verbal child develop language skills. Participatory design (PD) is frequently regarded as a c...

Authors: Luciana Correia Lima de Faria Borges, Lucia Vilela Leite Filgueiras, Cristiano Maciel and Vinicius Carvalho Pereira

A data warehouse to support web site automation

Due to the constant demand for new information and timely updates of services and content in order to satisfy the user’s needs, web site automation has emerged as a solution to automate several personalization...

Authors: Marcos Aurélio Domingues, Carlos Soares, Alípio Mário Jorge and Solange Oliveira Rezende

Evaluating different strategies for integration testing of aspect-oriented programs

The determination of an order for integration and testing of aspects and classes is a difficult optimization problem. This order should be associated to a minimal possible stubbing cost. To determine such orde...

Authors: Wesley Klewerton Guez Assunção, Thelma Elita Colanzi, Silvia Regina Vergilio and Aurora Trinidad Ramirez Pozo

Dynamic constrained coalition formation among electric vehicles

The use of electric vehicles (EVs) and vehicle-to-grid (V2G) technologies have been advocated as an efficient way to reduce the intermittency of renewable energy sources in smart grids. However, operating on V...

Authors: Gabriel de O Ramos, Juan C Burguillo and Ana LC Bazzan

Findings on ranking evaluation functions for feature weighting in image retrieval

There are substantial benefits to be gained from ranking optimization in several information retrieval and recommendation systems. However, the analysis of ranking evaluation functions (REFs), which play a maj...

Authors: Sergio F da Silva, Letricia PS Avalhais, Marcos A Batista, Celia AZ Barcelos and Agma JM Traina

Factorial design analysis applied to the performance of parallel evolutionary algorithms

Parallel computing is a powerful way to reduce computation time and to improve the quality of solutions of evolutionary algorithms (EAs). At first, parallel EAs (PEAs) ran on very expensive and not easily avai...

Authors: Mônica S Pais, Igor S Peretta, Keiji Yamanaka and Edmilson R Pinto

A case study of contributor behavior in Q&A site and tags: the importance of prominent profiles in community productivity

Question-and-answer (Q&A) sites have shown to be a valuable resource for helping people to solve their everyday problems. These sites currently enable a large number of contributors to exchange expertise by di...

Authors: Adabriand Furtado, Nigini Oliveira and Nazareno Andrade

PQR sort: using PQR trees for binary matrix reorganization

Reorganization of rows and columns of a matrix does not modify data but may ease or impair visual analysis of data similarities in this structure, according to Gestalt spatial proximity laws. However, there ar...

Authors: Celmar Guimarães da Silva, Marivaldo Felipe de Melo, Felipi de Paula e Silva and João Meidanis

Testing the robustness of controllers for self-adaptive systems

Self-adaptive systems are software-intensive systems endowed with the ability to respond to a variety of changes that may occur in their environment, goals, or the system itself by adapting their structure and...

Authors: Javier Cámara, Rogério de Lemos, Nuno Laranjeiro, Rafael Ventura and Marco Vieira

An automated black box approach for web vulnerability identification and attack scenario generation

Web applications have become increasingly vulnerable and exposed to malicious attacks that could affect essential properties of information systems such as confidentiality, integrity, or availability. To cope ...

Authors: Rim Akrout, Eric Alata, Mohamed Kaaniche and Vincent Nicomette

A path to automated service creation via semi-automation levels

The manual creation of new Internet- and IT-based applications is currently a limiting factor in enabling new and innovative services to be quickly available. We advocate that semi-automated service creation t...

Authors: Ernani Azevêdo, Carlos Kamienski, Ramide Dantas, Börje Ohlman and Djamel Sadok

Editorial

Authors: Maria Cristina Ferreira de Oliveira

Microalgae classification using semi-supervised and active learning based on Gaussian mixture models

Microalgae are unicellular organisms that have different shapes, sizes and structures. Classifying these microalgae manually can be an expensive task, because thousands of microalgae can be found in even a sma...

Authors: Paulo Drews- Jr., Rafael G. Colares, Pablo Machado, Matheus de Faria, Amália Detoni and Virgínia Tavano

Survey on automatic transcription of music

An automatic music transcriber is a device that detects, without human interference, the musical gestures required to play a particular piece. Many techniques have been proposed to solve the problem of automat...

Authors: Tiago Fernandes Tavares, Jayme Garcia Arnal Barbedo, Romis Attux and Amauri Lopes

Mechanized metatheory for a \(\lambda \)-calculus with trust types

As computer programs become increasingly complex, techniques for ensuring trustworthiness of information manipulated by them become critical. In this work, we use the Coq proof assistant to formalise a

Authors: Rodrigo Ribeiro, Lucília Figueiredo and Carlos Camarão

Editorial

Authors: Maria Cristina Ferreira de Oliveira

The evolution of agile software development in Brazil

Agile software development methods have been increasingly adopted worldwide and became one of the mainstream software development approaches. Agile methods have also had an impact on software engineering educa...

Authors: Claudia de O. Melo, Viviane Santos, Eduardo Katayama, Hugo Corbucci, Rafael Prikladnicki, Alfredo Goldman and Fabio Kon

A systematic review on keystroke dynamics

Computing and communication systems have improved our way of life, but have also contributed to an increased data exposure and, consequently, to identity theft. A possible way to overcome this issue is by the ...

Authors: Paulo Henrique Pisani and Ana Carolina Lorena

A review on Relation Extraction with an eye on Portuguese

The task of Relation Extraction is one of the main challenges in Natural Language Processing. We present a review of the state-of-the-art for Relation Extraction in free texts, addressing the progress and diff...

Authors: Sandra Collovini de Abreu, Tiago Luis Bonamigo and Renata Vieira

Syntenic global alignment and its application to the gene prediction problem

Given the increasing number of available genomic sequences, one now faces the task of identifying their protein coding regions. The gene prediction problem can be addressed in several ways, and one of the most...

Authors: Said S. Adi and Carlos E. Ferreira

CogTRA: a deployable mechanism for cognitive transmission rate adaptation in IEEE 802.11 networks

Wireless local area networks have become vastly popular, and IEEE 802.11 is the chosen standard for almost all wireless devices. This standard specifies several modulation and channel coding techniques that mu...

Authors: Luciano J. Chaves, Edmundo R. M. Madeira and Islene C. Garcia

BitTorrent traffic from a caching perspective

BitTorrent currently contributes a significant amount of inter-ISP traffic. This has motivated research and development to explore caching and locality-aware neighbor selection mechanisms for costly traffic re...

Authors: Lesandro Ponciano, Nazareno Andrade and Francisco Brasileiro

Link prediction using a probabilistic description logic

Due to the growing interest in social networks, link prediction has received significant attention. Link prediction is mostly based on graph-based features, with some recent approaches focusing on domain seman...

Authors: José Eduardo Ochoa Luna, Kate Revoredo and Fabio Gagliardi Cozman

A strategy for preparing software organizations for statistical process control

Software organizations have increased their interest in software process improvement (SPI). Nowadays, there are several frameworks that support SPI implementation. Some of them, such as CMMI (Capability Maturi...

Authors: Monalessa Perini Barcellos, Ricardo de Almeida Falbo and Ana Regina Rocha

Terminating constraint set satisfiability and simplification algorithms for context-dependent overloading

Algorithms for constraint set satisfiability and simplification of Haskell type class constraints are used during type inference in order to allow the inference of more accurate types and to detect ambiguity. ...

Authors: Rodrigo Ribeiro, Carlos Camarão and Lucília Figueiredo

A survey on automatic techniques for enhancement and analysis of digital photography

The fast growth in the consumer digital photography industry during the past decade has led to the acquisition and storage of large personal and public digital collections containing photos with different qual...

Authors: Claudio S. V. C. Cavalcanti, Herman Martins Gomes and José Eustáquio Rangel De Queiroz

Functional test data generation for Simulink-like models

Embedded systems are increasingly present in many electronic devices and is often related to critical applications. Therefore, the need for a well planned and executed testing procedure is even higher. We inte...

Authors: Rodrigo Fraxino Araujo, Marcio Eduardo Delamaro and Jose Carlos Maldonado

A conceptual-driven survey on future internet requirements, technologies, and challenges

Nowadays, research initiatives to redesign the Internet are popping up around the world. Each of these projects has a particular focus and its own set of design requirements and key technologies. The panorama ...

Authors: Antonio Marcos Alberti

Challenges for mesoscale climatology execution on experimental grid computing systems

This paper discusses the challenges of executing a long-term application on a computational grid, which generates the climatology of the atmospheric numerical model BRAMS (Brazilian development on Regional Atmosp...

Authors: Eugenio Sper de Almeida, Haroldo Fraga de Campos Velho and Airam Jonatas Preto

A Hajós-like theorem for weighted coloring

The Hajós’ Theorem (Wiss Z Martin Luther Univ Math-Natur Reihe, 10, pp 116–117, 1961) shows a necessary and sufficient condition for the chromatic number of a given graph ...

Authors: J. Araujo and C. Linhares Sales

Scrum adoption and architectural extensions in developing new service applications of large financial IT systems

The use of modern agile software development methods in large organisations requires tailoring agile development to the organisations’ needs. This study concentrated on studying integrating software product li...

Authors: Tuomas Ihme

Marching cubes technique for volumetric visualization accelerated with graphics processing units

Volume visualization has numerous applications that benefit different knowledge domains, such as biology, medicine, meteorology, oceanography, geology, among others. With the continuous advances of technology,...

Authors: Marcos Vinicius Mussel Cirne and Hélio Pedrini