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Publications

Publications by CRIIS

2010

A framework to support the tourist's information-needs Based on a ubiquitous approach

Authors
Carvalho, A; Cunha, CR; Morais, EP;

Publication
Business Transformation through Innovation and Knowledge Management: An Academic Perspective - Proceedings of the 14th International Business Information Management Association Conference, IBIMA 2010

Abstract
Nowadays, tourists are increasingly thirsty for information on anything that surrounds him. With the Information Communication Technologies (ICT) evolution that supports the ubiquity, it is necessary to rethink the available models of information and services to tourists. With the evolution of mobile devices, with wireless access, together with the decreasing of the network traffic costs and with the increasing number of access points of wireless access, becomes more common and attractive. Therefore, in this paper we present an analysis of the state of the art of the support applications for tourists for mobile environments, setting them according to the development technologies. In addition, it is also presented a suitable framework to support the tourist's needs based on a ubiquitous approach.

2010

Moderate electric fields can inactivate Escherichia coli at room temperature

Authors
Machado, LF; Pereira, RN; Martins, RC; Teixeira, JA; Vicente, AA;

Publication
JOURNAL OF FOOD ENGINEERING

Abstract
The inactivation of Escherichia coli using moderate electric fields (MEF) below 25 degrees C, was investigated. Keeping the temperature always below 25 degrees C demonstrated that electric fields are involved in the inactivation of E call, without possible synergistic temperature effects. Electric fields above 220 V cm(-1) promoted death rates of 3 log(10) cycles of E coli in less than 6 min, and even higher rates at greater electric fields, while presumably overcoming the thermal degradation caused by conventional high temperature treatments. A non-thermal model was proposed that successfully describes the E. coli death kinetics under this treatment. SEM observations of E. coli cells after the exposure to the MEF treatment, revealed changes at the cell membrane level, indicating a possible cause for the cell death rates. These results show that this treatment holds potential for sterilization of thermolabile products (e.g. serum and other physiological fluids, food products), by itself or as a complement of the traditional heat-dependent techniques.

2010

FRACTIONAL-ORDER CONTROL OF A ROBOTIC BIRD

Authors
Couceiro, MS; Fonseca Ferreira, NMF; Tenreiro Machado, JAT;

Publication
PROCEEDINGS OF ASME INTERNATIONAL DESIGN ENGINEERING TECHNICAL CONFERENCES AND COMPUTERS AND INFORMATION IN ENGINEERING CONFERENCE, VOL 4, PTS A-C

Abstract
In this paper it is studied the relation between the angle of attack and the velocity of the bird, the tail influence over the bird trajectory, the gliding and the flapping flight in a closed loop with fractional order controllers. The results are positive for the design and construction of flying robots having similarities with flying animals. The development of computational simulation based on the dynamic of the robotic bird that should allow testing strategies and algorithms of control.

2010

BIOLOGICAL INSPIRED FLYING ROBOT

Authors
Couceiro, MS; Figueiredo, CM; Fonseca Ferreira, NMF; Tenreiro Machado, JAT;

Publication
PROCEEDINGS OF THE ASME INTERNATIONAL DESIGN ENGINEERING TECHNICAL CONFERENCES AND COMPUTERS AND INFORMATION IN ENGINEERING CONFERENCE, VOL 7, PTS A AND B

Abstract
This paper presents the development of computational simulation based on the dynamics of a robotic bird. The study analyze the wing angle of attack and the velocity of the bird, the tail influence, the gliding flight and the flapping flight with different strategies and algorithms of control. The results are positive for the construction of flying robots. Some highlights are given about the fist implemented architecture of the structure of a robotic bird. This platform consists on a body, wings and tail with actuators independently controlled though a microcontroller; a radio transmission system and batteries are used in order to avoid wired connections between the computer and the robot.

2010

Modeling and control of a dragonfly-like robot

Authors
Ferreira, NMF; Couceiro, MS; Tenreiro MacHado, JA;

Publication
Journal of Control Science and Engineering

Abstract
Dragonflies demonstrate unique and superior flight performances than most of the other insect species and birds. They are equipped with two pairs of independently controlled wings granting an unmatchable flying performance and robustness. In this paper, the dynamics of a dragonfly-inspired robot is studied. The system performance is analyzed in terms of time response and robustness. The development of computational simulation based on the dynamics of the robotic dragonfly allows the test of different control algorithms. We study different movements, the dynamics, and the level of dexterity in wing motion of the dragonfly. The results are positive for the construction of flying platforms that effectively mimic the kinematics and dynamics of dragonflies and potentially exhibit superior flight performance than existing flying platforms. Copyright © 2010 Micael S. Couceiro et al.

2010

Application of fractional algorithms in the control of a robotic bird

Authors
Couceiro, MS; Ferreira, NMF; Machado, JAT;

Publication
COMMUNICATIONS IN NONLINEAR SCIENCE AND NUMERICAL SIMULATION

Abstract
In this paper. it is studied the dynamics of the robotic bird in terms of time response and robustness. It is analyzed the wing angle of attack and the velocity of the bird, the tail influence, the gliding flight and the flapping flight. The results are positive for the construction of flying robots. The development of computational simulation based on the dynamic of the robotic bird should allow testing strategies and different algorithms of control such as integer and fractional controllers. Crown Copyright

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