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Optimization of efficiency in hyperthermia requires a precise and non-invasive estimation of internal distribution of temperature. Although there are several research trends for ultrasonic temperature estimation, efficient equipments for its use in the clinical practice are not still available. The main objective of this work was to research about the(More)
This article describes a patient training evolution to achieve myoelectric control in the remnant limb. The methodology is divided in two main stages: (i) the training procedure, where the patient is submitted to a protocol for educating the muscles of the remnant limb, and (ii) myoelectric signal acquisition and analysis, in order to measure the patient(More)
An spectral analysis technique, that establishes a linear relation between the temperature changes in a body and the frequency displacement in the overtone peaks being displayed in the power spectral density (PSD) of ultrasonic echo-signal, has been improved and applied by the paper authors to estimate temperature gradients induced inside a biological(More)
Methods for characterizing ultrasonic therapy equipment rapidly and easily have to be implemented in order to avoid damages to patients; the existent methods measure different parameters in the ultrasonic beam that can be used to determine if the equipment works appropriately. In this paper, a comparison of three methods to characterize the ultrasonic beam(More)
The validation of a blood flow meter is presented. This flow meter is based on the transit time method that uses two ultrasound transducers and a reflector. The measuring is based on the time difference of the upstream and the downstream ultrasound transit time. The validation was based on the norm ANSI Std. N42.17A-2003 of blood flow protocol. We used a(More)
Objectives. To present a quantitative comparison of thermal patterns produced by the piston-in-a-baffle approach with those generated by a physiotherapy ultrasonic device and to show the dependency among thermal patterns and acoustic intensity distributions. Methods. The finite element (FE) method was used to model an ideal acoustic field and the produced(More)
This paper proposes a novel method for sensing obstacles and hand grasping activities in electromechanical arm prosthesis. The described method is based on indirectly sensing 'Stall' condition in prosthesis actuators through hall-effect sensors already embedded on its dc motors, thus not requiring external sensors. To test the proposed methodology, an(More)
Therapeutic ultrasound can induce changes in tissues by means of thermal and nonthermal effects. It is proposed for treatment of some brain pathologies such as Alzheimer's, Parkinson's, Huntington's diseases, and cancer. However, cranium highly absorbs ultrasound reducing transmission efficiency. There are clinical applications of transcranial focused(More)
This paper presents a noise immunity analysis of time delay estimation (TDE) techniques used on ultrasonic echoes for non invasive temperature estimation. Four methods are analyzed. The methodology consists on corrupting a simulated ultrasonic signal (ideal signal) with white noise and a signal-to-noise ratio of 3 dB and 6 dB. After this, noise immunity(More)