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Publications

2014

Minehunting Mission Planning for Autonomous Underwater Systems Using Evolutionary Algorithms

Authors
Abreu, N; Matos, A;

Publication
Unmanned Systems

Abstract
Autonomous underwater vehicles (AUVs) are increasingly being used to perform mine countermeasures (MCM) operations but its capabilities are limited by the efficiency of the planning process. Here we study the problem of multiobjective MCM mission planning with AUVs. The vehicle should cover the operating area while maximizing the probability of detecting the targets and minimizing the required energy and time to complete the mission. A multi-stage algorithm is proposed and evaluated. Our algorithm combines an evolutionary algorithm (EA) with a local search procedure, aiming at a more flexible and effective exploration and exploitation of the search space. An artificial neural network (ANN) model was also integrated in the evolutionary procedure to guide the search. The combination of different techniques creates another problem, related to the high amount of parameters that needs to be tuned. Thus, the effect of these parameters on the quality of the obtained Pareto Front was assessed. This allowed us to define an adaptive tuning procedure to control the parameters while the algorithm is executed. Our algorithm is compared against an implementation of a known EA as well as another mission planner and the results from the experiments show that the proposed strategy can efficiently identify a higher quality solution set. © 2014 World Scientific Publishing Company.

2014

Young Swimmers' Classification Based on Kinematics, Hydrodynamics, and Anthropometrics

Authors
Barbosa, TM; Morais, JE; Costa, MJ; Goncalves, J; Marinho, DA; Silva, AJ;

Publication
JOURNAL OF APPLIED BIOMECHANICS

Abstract
The aim of this article has been to classify swimmers based on kinematics, hydrodynamics, and anthropometrics. Sixty-seven young swimmers made a maximal 25 m front-crawl to measure with a speedometer the swimming velocity (v), speed-fluctuation (dv) and dv normalized to v (dv/v). Another two 25 m bouts with and without carrying a perturbation device were made to estimate active drag coefficient (C-Da). Trunk transverse surface area (S) was measured with photogrammetric technique on land and in the hydrodynamic position. Cluster 1 was related to swimmers with a high speed fluctuation (ie, dv and dv/v), cluster 2 with anthropometrics (ie, S) and cluster 3 with a high hydrodynamic profile (ie, C-Da). The variable that seems to discriminate better the clusters was the dv/v (F = 53.680; P < .001), followed by the dv (F = 28.506; P < .001), C-Da (F = 21.025; P < .001), S (F = 6.297; P < .01) and v (F = 5.375; P = .01). Stepwise discriminant analysis extracted 2 functions: Function 1 was mainly defined by dv/v and S (74.3% of variance), whereas function 2 was mainly defined by C-Da (25.7% of variance). It can be concluded that kinematics, hydrodynamics and anthropometrics are determinant domains in which to classify and characterize young swimmers' profiles.

2014

Constraints and Requirements in Designing an e-learning Environment

Authors
Martins, MJM; Barbosa, FPM; Ferreira, CM; Valdez, MT;

Publication
2014 25TH ANNUAL CONFERENCE EAEEIE (EAEEIE)

Abstract
Nowadays, education extends beyond the field of formal education delivered in universities and colleges, and is increasingly based on new technological developments. Long Life Learning (LLL) is a fundamental tool in today's world in order to remain competitive in the market. The ease of access to the Internet and computer technologies has turned into a new field for developing applications which can be distributed worldwide in an almost instantaneous manner, but must be appropriately designed in order to achieve their goals. Quality e-learning courseware requires several aspects to be covered in order to achieve its purposes. These include a thorough knowledge of the content as well as methods of delivery and learning theory. These requirements were taken into account in the development of a virtual-lab environment, named VEMA, developed by one of the authors and used in the Bachelor and Master's classes.

2014

Short paper: CHIPS: content-based heuristics for improving photo privacy for smartphones

Authors
Tan, J; Drolia, U; Martins, R; Gandhi, R; Narasimhan, P;

Publication
7th ACM Conference on Security & Privacy in Wireless and Mobile Networks, WiSec'14, Oxford, United Kingdom, July 23-25, 2014

Abstract
The Android permissions system provides all-or-nothing access to users' photos stored on smartphones, and the permissions which control access to stored photos can be confusing to the average user. Our analysis found that 73% of the top 250 free apps on the Google Play store have permissions that may not reflect their ability to access stored photos. We propose CHIPS, a unique content-based fine-grained run-time access control system for stored photos for Android which requires minimal user assistance, runs entirely locally, and provides low-level enforcement. CHIPS can recognize faces with minimal user training to deny apps access to photos with known faces. CHIPS's privacy identification has low overheads as privacy checks are cached, and is accurate, with false-positive and false-negative rates of less than 8%. © 2014 ACM.

2014

Shamanic interfaces for computers and gaming platforms

Authors
Carvalho, Filipe; Morgado, Leonel; Coelho, António;

Publication
INForum 2014

Abstract
Natural user interfaces are becoming widespread as a focus of research in human-computer interaction. Gestural interaction is an important part of this field, but generally done by mimicry. This raises concerns such as the necessity of creating abstractions for non-imitable commands and the difficulty of finding gestures that are meaningful for a worldwide audience. Cultural backgrounds impart different meanings to gestures. In this research , we explore the concept of allowing individuals to interact with computer systems using gesture from the individual’s own culture, focusing on a software engineering approach to support this idea. The aim is to leverage the rich semantics of non-mimicry cultural gestures to expand gestural interaction to support abstract commands for instructions that do not have a matching gestural imitation. This approach also holds the potential to support the learning of gestural commands, by linking them to the cultural background of each user. The proposed software engineering approach demonstrates the feasibility of planning applications with commands in mind, not specific gestures, separating concerns between gestural identification (which can include cultural background elements) and actual commands.

2014

ESO-ESMO 2nd international consensus guidelines for advanced breast cancer (ABC2)

Authors
Cardoso, F; Costa, A; Norton, L; Senkus, E; Aapro, M; Andre, F; Barrios, CH; Bergh, J; Biganzoli, L; Blackwell, KL; Cardoso, MJ; Cufer, T; El Saghir, N; Fallowfield, L; Fenech, D; Francis, P; Gelmon, K; Giordano, SH; Gligorov, J; Goldhirsch, A; Harbeck, N; Houssami, N; Hudis, C; Kaufman, B; Krop, I; Kyriakides, S; Lin, UN; Mayer, M; Merjaver, SD; Nordstrom, EB; Pagani, O; Partridge, A; Penault Llorca, F; Piccart, MJ; Rugo, H; Sledge, G; Thomssen, C; van't Veer, L; Vorobiof, D; Vrieling, C; West, N; Xu, B; Winer, E;

Publication
ANNALS OF ONCOLOGY

Abstract

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