Articles

Secure self-recovery watermarking scheme for error concealment and tampering detection

In this paper, we present a method for protecting and restoring lost or tampered information in images or videos using secure watermarks. The proposed method consists of a combination of techniques that are ab...

Authors: Pedro Garcia Freitas, Ronaldo Rigoni and Mylène C. Q. Farias

Some results on extension of lattice-valued QL-implications

A very important issue in lattice theory is how to extend a given operator preserving its algebraic properties. For lattice-valued fuzzy operators framework, in 2008 Saminger-Platz presented a way to extend t-...

Authors: Eduardo S. Palmeira, Benjamín R.C. Bedregal and José Anchieta G. dos Santos

LODPRO: learning objects development process

Research concerning to the use of technology in education has received increasing attention from scholars in recent years. This attention has resulted in new educational materials demanding creative ways to pl...

Authors: Leandro Marques Queiros, Denis Silva da Silveira, Jorge da Silva Correia-Neto and Guilherme Vilar

Rain gauge simulator and first tests with a new mobile climate alert system in Brazil

Recent national developments in alert systems are the main motivation of this work. The aim is to provide an account on the development and first tests of a new Meteorological Alert System—MAS for mobile devic...

Authors: Ademir L. Xavier Jr, Daniel Bonatti and Sergio Celaschi

Bounded model checking for fixed-point digital filters

Currently, digital filters are employed in a wide range of signal processing applications, using fixed- and floating-point processors. Regarding the former, some filter implementations may be highly prone to e...

Authors: Renato B. Abreu, Mikhail Y. R. Gadelha, Lucas C. Cordeiro, Eddie B. de Lima Filho and Waldir S. da Silva Jr

Practical use of a latent semantic analysis (LSA) model for automatic evaluation of written answers

This paper presents research of an application of a latent semantic analysis (LSA) model for the automatic evaluation of short answers (25 to 70 words) to open-ended questions. In order to reach a viable appli...

Authors: João Carlos Alves dos Santos and Eloi Luiz Favero

Testing of aspect-oriented programs: difficulties and lessons learned based on theoretical and practical experience

Since the first discussions of new challenges posed by aspect-oriented programming (AOP) to software testing, the real difficulties of testing aspect-oriented (AO) programs have not been properly analysed. Fir...

Authors: Fabiano C. Ferrari, Bruno B. P. Cafeo, Thiago G. Levin, Jésus T. S. Lacerda, Otávio A. L. Lemos, José C. Maldonado and Paulo C. Masiero

A hybrid particle swarm optimization and harmony search algorithm approach for multi-objective test case selection

Test case (TC) selection is considered a hard problem, due to the high number of possible combinations to consider. Search-based optimization strategies arise as a promising way to treat this problem, as they exp...

Authors: Luciano Soares de Souza, Ricardo Bastos Cavalcante Prudêncio and Flávia A. de Barros

Complexity of greedy edge-colouring

The Grundy index of a graph G =(V, E) is the greatest number of colours that the greedy edge-colouring algorithm can use on G. We prove that the problem of determining the Grundy index of a graph G=(V, E) is NP-h...

Authors: Frédéric Havet, A. Karolinna Maia and Min-Li Yu

Utterance copy through analysis-by-synthesis using genetic algorithm

Utterance copy consists in estimating the input parameters to reconstruct a speech signal using a speech synthesizer. This process is distinct from the more traditional text-to-speech but yet used in many area...

Authors: Fabíola Araújo, Aldebaro Klautau and José Filho

Improving workflow design by mining reusable tasks

With the increasing popularity of scientific workflow management systems (SWfMS), more and more workflow specifications are becoming available. Such specifications contain precious knowledge that can be reused...

Authors: Frederico E. Tosta, Vanessa Braganholo, Leonardo Murta and Marta Mattoso

Does test-driven development improve class design? A qualitative study on developers’ perceptions

Developers commonly affirm that writing unit tests improve internal quality of a software, besides a more obvious effect on external quality. This is particularly common among Test-Driven Development (TDD) pac...

Authors: Maurício Aniche and Marco Aurélio Gerosa

Software engineering research in Brazil from the perspective of young researchers: a panorama of the last decade

After graduating and starting a career as a professor, a young researcher usually finds him/herself lost due to a huge amount of new obligations and opportunities. Choosing the best strategy to guide his/her c...

Authors: Arilo C. Dias-Neto, Rafael Prikladnicki, Márcio de O. Barros and Leonardo G. P. Murta

A novel caching algorithm for VoD proxy implementation and its evaluation including a new set of metrics for efficiency analysis

Video on demand (VoD) is a fast-growing digital service that requires a substantial amount of hardware resources for its implementation. To reduce the costs of running this service, an alternative is to use pr...

Authors: Bruno S Neves, Anderson S Venturini and Altamiro A Susin

A combined approach for concern identification in KDM models

Systems are considered legacy when their maintenance costs raise to unmanageable levels, but they still deliver valuable benefits for companies. One intrinsic problem of this kind of system is the presence of ...

Authors: Daniel San Martín Santibáñez, Rafael Serapilha Durelli and Valter Vieira de Camargo

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

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

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

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

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

Editorial

Authors: Maria Cristina Ferreira de Oliveira

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

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

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

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