Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99


Any time

2020 ( 6 )

2019 ( 192 )

2018 ( 266 )

2017 ( 273 )

Custom range...

Search Results: 1 - 10 of 174238 matches for " Jose F. Rodrigues Jr "
All listed articles are free for downloading (OA Articles)
Page 1 /174238
Display every page Item
ORFEL: super-fast detection of defamation and illegitimate promotion in online recommendation
Gabriel Gimenes,Jose F. Rodrigues Jr,Robson Cordeiro
Computer Science , 2015,
Abstract: What if a successful company starts to receive a torrent of low-valued (one or two stars) recommendations in its mobile apps from multiple users within a short (say one month) period? Is it legitimate evidence that the apps have lost quality, or an intentional plan (via lockstep behavior) to steal market share through defamation? In case of a systematic attack to one's reputation, it might not be possible to manually discern between legitimate and fraudulent interaction in the immense universe of possibilities of user-product recommendation. Previous works have focused on this issue, but none of them has considered the context, modeling, and scale that we work with in this paper. We propose one novel method named Online-Recommendation Fraud ExcLuder (\ORFEL) to detect defamation and/or illegitimate promotion of online products using vertex-centric asynchronous parallel processing of bipartite (users-products) graphs. With an innovative algorithm, our results demonstrate efficacy -- detecting over $95\%$ of potential attacks; and efficiency -- at least two orders of magnitude faster than the state-of-the-art. Over our new methodology, we introduce three contributions: (1) a new algorithmic solution; (2) a scalable approach; and (3) a novel context and modeling of the problem, which now addresses both defamation and illegitimate promotion. Our work deals with relevant issues of the Web 2.0, potentially augmenting the credibility of online recommendation to prevent losses to both customers and vendors.
The Spatial-Perceptual Design Space: a new comprehension for Data Visualization
Jose F. Rodrigues Jr,Agma J. M. Traina,Maria C. F. Oliveira,Caetano Traina Jr
Computer Science , 2015, DOI: 10.1057/palgrave.ivs.9500161
Abstract: We revisit the design space of visualizations aiming at identifying and relating its components. In this sense, we establish a model to examine the process through which visualizations become expressive for users. This model has leaded us to a taxonomy oriented to the human visual perception, a conceptualization that provides natural criteria in order to delineate a novel understanding for the visualization design space. The new organization of concepts that we introduce is our main contribution: a grammar for the visualization design based on the review of former works and of classical and state-of-the-art techniques. Like so, the paper is presented as a survey whose structure introduces a new conceptualization for the space of techniques concerning visual analysis.
Reviewing Data Visualization: an Analytical Taxonomical Study
Jose F. Rodrigues Jr.,Agma J. M. Traina,Maria Cristina F. de Oliveira,Caetano Traina Jr
Computer Science , 2015,
Abstract: This paper presents an analytical taxonomy that can suitably describe, rather than simply classify, techniques for data presentation. Unlike previous works, we do not consider particular aspects of visualization techniques, but their mechanisms and foundational vision perception. Instead of just adjusting visualization research to a classification system, our aim is to better understand its process. For doing so, we depart from elementary concepts to reach a model that can describe how visualization techniques work and how they convey meaning.
BoWFire: Detection of Fire in Still Images by Integrating Pixel Color and Texture Analysis
Daniel Y. T. Chino,Letricia P. S. Avalhais,Jose F. Rodrigues Jr.,Agma J. M. Traina
Computer Science , 2015,
Abstract: Emergency events involving fire are potentially harmful, demanding a fast and precise decision making. The use of crowdsourcing image and videos on crisis management systems can aid in these situations by providing more information than verbal/textual descriptions. Due to the usual high volume of data, automatic solutions need to discard non-relevant content without losing relevant information. There are several methods for fire detection on video using color-based models. However, they are not adequate for still image processing, because they can suffer on high false-positive results. These methods also suffer from parameters with little physical meaning, which makes fine tuning a difficult task. In this context, we propose a novel fire detection method for still images that uses classification based on color features combined with texture classification on superpixel regions. Our method uses a reduced number of parameters if compared to previous works, easing the process of fine tuning the method. Results show the effectiveness of our method of reducing false-positives while its precision remains compatible with the state-of-the-art methods.
M-Flash: Fast Billion-scale Graph Computation Using Block Partition Model
Hugo Gualdron,Robson Cordeiro,Jose F. Rodrigues Jr.,Duen Horng,Chau,Minsuk Kahng,U Kang
Computer Science , 2015,
Abstract: Recent graph computation approaches such as GraphChi, X-Stream, TurboGraph and MMap demonstrated that a single PC can perform efficient computation on billion-scale graphs. While they use different techniques to achieve scalability through optimizing I/O operations, such optimization often does not fully exploit the capabilities of modern hard drives. Our main contributions are: (1) we propose a novel and scalable graph computation framework called M-Flash that uses a new, bimodal block processing strategy (\emph{BBP}) to boost computation speed by minimizing I/O cost; (2) M-Flash includes a flexible and deliberatively simple programming model that enables us to easily implement popular and essential graph algorithms, including the \textit{first} single-machine billion-scale eigensolver; and (3) we performed extensive experiments on real graphs with up to 6.6 billion edges, demonstrating M-Flash's consistent and significant speed-up over state-of-the-art approaches.
Large Graph Analysis in the GMine System
Jose F. Rodrigues Jr.,Hanghang Tong,Jia-Yu Pan,Agma J. M. Traina,Caetano Traina Jr.,Christos Faloutsos
Computer Science , 2015, DOI: 10.1109/TKDE.2011.199
Abstract: Current applications have produced graphs on the order of hundreds of thousands of nodes and millions of edges. To take advantage of such graphs, one must be able to find patterns, outliers and communities. These tasks are better performed in an interactive environment, where human expertise can guide the process. For large graphs, though, there are some challenges: the excessive processing requirements are prohibitive, and drawing hundred-thousand nodes results in cluttered images hard to comprehend. To cope with these problems, we propose an innovative framework suited for any kind of tree-like graph visual design. GMine integrates (a) a representation for graphs organized as hierarchies of partitions - the concepts of SuperGraph and Graph-Tree; and (b) a graph summarization methodology - CEPS. Our graph representation deals with the problem of tracing the connection aspects of a graph hierarchy with sub linear complexity, allowing one to grasp the neighborhood of a single node or of a group of nodes in a single click. As a proof of concept, the visual environment of GMine is instantiated as a system in which large graphs can be investigated globally and locally.
A survey on Information Visualization in light of Vision and Cognitive sciences
Jose F. Rodrigues Jr,Luciana A. M. Zaina,Maria C. F. de Oliveira,Agma J. M. Traina
Computer Science , 2015,
Abstract: Information visualization techniques are built on a context with too many factors, making it difficult to systematically deal with their underlying bases. In the intent of promoting a better comprehension, here, we survey concepts on vision, cognition, and Information Visualization organized in a theorization named Visual Expression Model. With a reduced level of complexity, our model organizes the bases of visualization techniques, nevertheless, it is complete enough to discuss guidelines related to design and analytical tasks. Organized in a coherent account, our work introduces the following contributions: (1) Theoretical compilation of vision, cognition, and Information Visualization, (2) Meticulous discussions supported by vast literature, and (3) Recommendations to have visualizations satisfy visual-cognitive aspects. We expect our contributions will improve the practice of InfoVis by promoting comprehension and by proposing the use of simple recommendations.
A unified theory for construction of arbitrary speeds (0 < = v < \infty) solutions of the relativistic wave equations
Waldyr A. Rodrigues Jr.,Jose E. Maiorino
Physics , 1997,
Abstract: Representing the relativistic physical fields as sections of the Clifford Bundle (or of the Spin-Clifford Bundle) of Minkowski spacetime we show that all the relativistic wave equations satisfied by these fields possess solutions traveling with arbitrary speeds $0 \leq v < \infty$. By giving rigorous mathematical definitions of reference frames and of the Principle of Relativity (PR) we prove that physical realizations of the $v > 1$ solutions of, e.g., the Maxwell equations imply in a breakdown of the PR, but in no contradiction at all with known physical facts.
The New Brazilian Power Quality Standard and a Low Cost Device Meter  [PDF]
Guilherme P. Colnago, Jose L. F. Vieira, Gilberto C. D. Sousa, Jose R. Macedo Jr.
Energy and Power Engineering (EPE) , 2012, DOI: 10.4236/epe.2012.43020
Abstract: This paper presents an overview about the new Brazilian Power Quality Standard and provides a low cost device PQ meter, developed and implemented to assist the national campaign to assess the Brazilian power quality indices, unknown until now. This work contributes with the search of a low cost devices PQ meter for a cost sensitive market, and introduces the new Brazilian Power Quality Standard to the international community.
Densidade linear do sistema de fibras elásticicas dos ligamentos patelar, cruzado anterior e cruzado posterior
Pecora, Jose Ricardo;Rodrigues, Consuelo Junqueira;Rodrigues Jr., Aldo Junqueira;Salom?o, Osny;
Acta Ortopédica Brasileira , 2001, DOI: 10.1590/S1413-78522001000100007
Abstract: in order to verify the improvement to choose the better ligament that may be used in knee surgical repair, we performed a comparative analysis of the amount of the elastic fibers system between the patellar and cruciates ligaments. samples of these ligaments obtained from seven human corpses were studied. histomorphometric study of the elastic fibers, stained by selective methods didn't show differences in the total amount of all types of elastic fibers, in all three ligaments studied. no difference either was found in the amount of mature elastic fibers. however, the amount of mature and elaunin elastic fibers was significantly different. the anterior cruciate ligament had a greater amount of mature and elaunin elastic fibers, responsible for elasticity. so, the posterior cruciate and the patellar ligaments have more oxytalan elastic fibers, responsible for resistance. we concluded that the posterior cruciate and the patellar ligaments have similar structure and seem more related to transmittance of force, whereas the anterior cruciate ligament is related to elasticity of the knee joint.
Page 1 /174238
Display every page Item

Copyright © 2008-2017 Open Access Library. All rights reserved.