2014
Autores
Trigueiros, P; Ribeiro, F; Reis, LP;
Publicação
RoboCup 2013: Robot World Cup XVII
Abstract
In RoboCup Middle Size league (MSL) the main referee uses assisting technology, controlled by a second referee, to support him, in particular for conveying referee decisions for robot players with the help of a wireless communication system. In this paper a vision-based system is introduced, able to interpret dynamic and static gestures of the referee, thus eliminating the need for a second one. The referee's gestures are interpreted by the system and sent directly to the Referee Box, which sends the proper commands to the robots. The system is divided into four modules: a real time hand tracking and feature extraction, a SVM (Support Vector Machine) for static hand posture identification, an HMM (Hidden Markov Model) for dynamic unistroke hand gesture recognition, and a FSM (Finite State Machine) to control the various system states transitions. The experimental results showed that the system works very reliably, being able to recognize the combination of gestures and hand postures in real-time. For the hand posture recognition, with the SVM model trained with the selected features, an accuracy of 98,2% was achieved. Also, the system has many advantages over the current implemented one, like avoiding the necessity of a second referee, working on noisy environments, working on wireless jammed situations. This system is easy to implement and train and may be an inexpensive solution.
2014
Autores
Silva, DC; Abreu, PH; Reis, LP; Oliveira, E;
Publicação
INFORMATION SCIENCES
Abstract
The work described in this paper is part of the development of a framework to support the joint execution of cooperative missions by a group of robotic vehicles, in a simulated, augmented or real environment. Such framework brings forward the need for formal languages in which to specify the group of vehicles that compose a team; the scenario in which they will operate; and the definition of the mission to be performed (surveillance, pollution detection, search and rescue operations, and so on). This paper presents the Mission Description Language (MDL), a XML dialect that describes the specifics of a mission to be performed by a team of autonomous vehicles. The MDL definition decomposes a mission into a number of possibly dependent phases and uses high-level concepts that facilitate the specification of a mission by both experts and non-experts. The dialect was defined using XML Schema, with all the required information being integrated in the definition. An interface was developed and incorporated into the framework, as to allow for the creation and edition of XML files following the defined schema. Once the information is correctly specified, it can be used in the framework, thus facilitating the process of mission specification and deployment. A survey answered by both practitioners and researchers shows that the degree of satisfaction with MDL is elevated (the overall evaluation of MDL achieved a 3.97 score (out of 5), with 82.05% of the answers being equal to or above 4); also, the usability of the interface was evaluated, having achieved a score of 82.9 in the SUS scale. These results imply that MDL is flexible enough to represent several types of missions, through a user-friendly interface.
2014
Autores
Martins, HF; Marques, MB; Frazao, O;
Publicação
APPLIED PHYSICS B-LASERS AND OPTICS
Abstract
In this work, the authors propose a new configuration for an intensity vibration sensor based on a Raman fiber laser. The linear cavity of the Raman fiber laser relies on the combination of a distributed Rayleigh mirror and fiber Bragg gratings, which are used as the sensing element and intensity filter. The sensor was able to measure vibrations with frequencies of up to 350 Hz with more than 50 dB of signal-to-noise ratio (SNR) and also the amplitude of the vibrations with a sensitivity of up to 0.57 +/- A 0.07 dB/mu I mu for vibrations with a maximum strain variation of up to 35 mu I mu. The main advantages of the proposed configuration are the simple scheme with high SNR for remote sensing and the easy possibility of multiplexing.
2014
Autores
Amaral, C; Florido, M; Costa, VS;
Publicação
FUNCTIONAL AND LOGIC PROGRAMMING, FLOPS 2014
Abstract
We present PrologCheck, an automatic tool for property-based testing of programs in the logic programming language Prolog with randomised test data generation. The tool is inspired by the well known QuickCheck, originally designed for the functional programming language Haskell. It includes features that deal with specific characteristics of Prolog such as its relational nature (as opposed to Haskell) and the absence of a strong type discipline. PrologCheck expressiveness stems from describing properties as Prolog goals. It enables the definition of custom test data generators for random testing tailored for the property to be tested. Further, it allows the use of a predicate specification language that supports types, modes and constraints on the number of successful computations. We evaluate our tool on a number of examples and apply it successfully to debug a Prolog library for AVL search trees.
2014
Autores
Heydarian Forushani, E; Shafie khah, M; Damavandi, MY; Catalao, JPS;
Publicação
TECHNOLOGICAL INNOVATION FOR COLLECTIVE AWARENESS SYSTEMS
Abstract
Aggregating the Demand Response (DR) is approved as an effective solution to improve the participation of consumers to wholesale electricity markets. DR aggregator can negotiate the amount of collected DR of their customers with transmission system operator, distributors, and retailers in Demand Response eXchange (DRX) market, in addition to participate in the energy market. In this paper, a framework has been proposed to optimize the participation of a DR aggregator in day-ahead energy and intraday DRX markets. In this regard, the DR aggregator optimizes its participation schedule and offering/bidding strategy in the mentioned markets according to behavior of its customers. For this purpose, the customers' participation is modeled using a Supply Function Equilibrium (SFE) model. In addition, due to uncertainties of market prices and the behavior of consumers, an appropriate risk measurement, CVaR, is incorporated to the optimization problem. The numerical results show the effectiveness of the proposed framework.
2014
Autores
Giordano, G; Brito, P;
Publicação
ANALYSIS AND MODELING OF COMPLEX DATA IN BEHAVIORAL AND SOCIAL SCIENCES
Abstract
Starting from the main idea of Symbolic Data Analysis to extend Statistics and Data Mining methods from first-order to second-order objects, we focus on network data-as defined in the framework of Social Network Analysis-to define a graph structure and the underlying network in the context of complex data objects. A Network Symbolic description is defined according to the statistical characterization of the network topological properties. We use suitable network measures, which are represented by means of symbolic variables. Their study through multidimensional data analysis, allows for the synthetic representation of a network as a point onto a metric space. The proposed approach is discussed on the basis of a simulation study considering three classical network growth processes.
The access to the final selection minute is only available to applicants.
Please check the confirmation e-mail of your application to obtain the access code.