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João Pessoa, Brazil

Kanovich M.,Queen Mary, University of London | Kanovich M.,National Research University Higher School of Economics | Kirigin T.B.,University of Rijeka | Nigam V.,Federal University of Paraba | And 3 more authors.
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2015

Many security protocols rely on the assumptions on the physical properties in which its protocol sessions will be carried out. For instance, Distance Bounding Protocols take into account the round trip time of messages and the transmission velocity to infer an upper bound of the distance between two agents. We classify such security protocols as Cyber-Physical. Time plays a key role in design and analysis of many of these protocols. This paper investigates the foundational differences and the impacts on the analysis when using models with discrete time and models with dense time. We show that there are attacks that can be found by models using dense time, but not when using discrete time. We illustrate this with a novel attack that can be carried out on most distance bounding protocols. In this attack, one exploits the execution delay of instructions during one clock cycle to convince a verifier that he is in a location different from his actual position. We propose a Multiset Rewriting model with dense time suitable for specifying cyber-physical security protocols. We introduce Circle-Configurations and show that they can be used to symbolically solve the reachability problem for our model. Finally, we show that for the important class of balanced theories the reachability problem is PSPACE-complete. © Springer-Verlag Berlin Heidelberg 2015.


Rached T.S.,Federal University of Campina Grande | De S. Santos D.F.,Signove Tecnologia S.A. | Perkusich A.,Federal University of Campina Grande | Almeida H.,Federal University of Campina Grande | De Almeida Holanda M.M.,Federal University of Paraba
2010 International Conference on Information Society, i-Society 2010 | Year: 2010

Assistive technologies have a major impact in the life of people with severe neuromuscular diseases in order to provide or extend functional abilities of people with special needs. Such technologies promote independent life, social inclusion and improve quality of life of disabled people. Brain-Computer Interface (BCI) is a recent technology that allows the direct communication between the brain and the environment. The development of systems that integrates BCI, smart devices and pervasive services enables motor disabled people to control devices anytime and anywhere. This paper presents an architecture for the development of BCI-aware pervasive systems to control multimedia devices. The user needs an electroencephalography (EEG) device and a smart device to interact with any multimedia device. This paper brings the implementation of a BCI-aware pervasive system that enables users to control the XBMC media center to play music or videos. © 2010 i-Society.


Ferreira D.A.P.,University of Sao Paulo | Nakagawa F.,University of Sao Paulo | Altafim R.A.C.,University of Sao Paulo | Da Silva J.F.R.,Elektro Electricity and Services | And 2 more authors.
2013 IEEE Electrical Insulation Conference, EIC 2013 | Year: 2013

Most Brazilian utility companies normally do not consider failures in distribution transformers to be a great economic issue, since detecting these faults can be more costly in terms of time and resources. Thus, proper policies for investigating faults in distribution transformers are usually disregarded by the power utilities and sometimes policies may not even exist. In this context, existing information on faulty distribution transformers may not contain important data. However, new laws affecting power distribution companies are becoming more severe and there are demands for greater efficiency. In this new scenario, a forensic methodology to analyze faults in distribution transformers, created some years ago by many utilities, has recently been resurrected with the analysis of 3,159 distribution transformers. This methodology is known as Forensic Analysis Applied to Distribution Transformers (FAADT). This paper, which analyzes eight damaged distribution transformers, randomly selected from ELEKTRO's distribution lines, validates and refines the FAADT methodology. In order to do this, in addition to FAADT parameters, other parameters, such as polarization and dielectric absorption indices, turns ratio, insulation resistance and physicochemical analyses were also verified. © 2013 IEEE.


Souto L.A.,Federal University of Paraba | Nascimento T.P.,Federal University of Paraba
Proceedings - 12th LARS Latin American Robotics Symposium and 3rd SBR Brazilian Robotics Symposium, LARS-SBR 2015 - Part of the Robotics Conferences 2015 | Year: 2015

When using RGB-D SLAM algorithms, a robot often takes into account dynamic and static objects during the 3D mapping step. This paper aims to present a novel approach in the mapping step of Simultaneous Localization and Mapping (SLAM) and map merging algorithms to a multi-robots system. The Object Subtraction Mapping (OS-Map) algorithm subtracts movable objects from the 3D environment and creates a clean 3D map. Therefore, it will be possible to merge the maps in a multi-robot scenario. With the availability of low-cost RGB-D sensors such as the Microsoft Kinect, our approach can be applied to low-cost robots. Both algorithms were applied to a TurtleBot 2 platform which has a RGB-D sensor as its main sensor. The results demonstrated the efficiency on generating and merging clean and accurate maps, using the OS-Map algorithm alongside a RGB-D SLAM approach. © 2015 IEEE.


Restivo M.T.,University of Porto | Lopes A.M.,University of Porto | MacHado L.D.S.,Federal University of Paraba | De Moraes R.M.,Federal University of Paraba
2011 IEEE Global Engineering Education Conference, EDUCON 2011 | Year: 2011

This work presents different approaches for illustrating one process of determining in the lab the Young Modulus, a material property that describes its stiffness and so is one of the most important properties in engineering design. It describes briefly a classical experimental procedure in a traditional lab, a remote accessed system, a remote & virtual accessed system haptically interacted and finally, a new approach under development, a virtual system with haptic interaction. Along the text some constrains will be discussed and the evolution for this new development will include a short discussion devoted to the increase in capabilities of the virtual experiment when integrating force feedback information and the authors attempt to consider the richness of such a solution compared with others described. © 2011 IEEE.

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