Search results for "Biomedical"
showing 10 items of 2328 documents
A multi-sensor multi-rate algorithm for motor rehabilitation with Augmented Reality devices
2016
Using Augmented Reality (AR) could offer stimuli to rehabilitation from neuro-motor disorders, since the patient can be aided in a better known reality than Virtual Reality (VR). The main goal for an AR system is to achieve a good quality of tracking the real object to align with virtual contents. Often a single sensor could not provide enough information to that end due to a low updating rate; therefore joining an other high updating rate sensor could be indispensable, but how to combine data from different sensors especially when they work all at different rates? In this paper an approach based on recursive parameter estimation, focusing on multi-rate tracking in AR devices is suggested. …
A mixed FES/EMG system for real time analysis of muscular fatigue
2010
International audience; In this article, we present a functional electrical stimulator allowing the extraction in real time of M-wave characteristics from resulting EMG recodings in order to quantify muscle fatigue. This system is composed of three parts. A Labview software managing the stimulation output and electromyogram (EMG) input signal, a hardware part amplifying the output and input signal and a link between the two previous parts which is made up from input/output module (NIdaq USB 6251). In order to characterize the fatigue level, the Continuous Wavelet Transform is applied yielding a local maxima detection. The fatigue is represented on a scale from 0 for a fine shaped muscle to …
Empirical mode decomposition and neural network for the classification of electroretinographic data
2013
The processing of biosignals is increasingly being utilized in ambulatory situations in order to extract significant signals' features that can help in clinical diagnosis. However, this task is hampered by the fact that biomedical signals exhibit a complex behaviour characterized by strong non-linear and non-stationary properties that cannot always be perceived by simple visual examination. New processing methods need be considered. In this context, we propose to apply a signal processing method, based on empirical mode decomposition and artificial neural networks, to analyse electroretinograms, i.e. the retinal response to a light flash, with the aim to detect and classify retinal diseases…
A full body musculoskeletal model based on flexible multibody simulation approach utilised in bone strain analysis during human locomotion
2011
Load-induced strains applied to bone can stimulate its development and adaptation. In order to quantify the incident strains within the skeleton, in vivo implementation of strain gauges on the surfaces of bone is typically used. However, in vivo strain measurements require invasive methodology that is challenging and limited to certain regions of superficial bones only such as the anterior surface of the tibia. Based on our previous study [Al Nazer et al. (2008) J Biomech. 41:1036-1043], an alternative numerical approach to analyse in vivo strains based on the flexible multibody simulation approach was proposed. The purpose of this study was to extend the idea of using the flexible multibod…
Take-off aerodynamics in ski jumping
2001
The effect of aerodynamic forces on the force-time characteristics of the simulated ski jumping take-off was examined in a wind tunnel. Vertical and horizontal ground reaction forces were recorded with a force plate installed under the wind tunnel floor. The jumpers performed take-offs in non-wind conditions and in various wind conditions (21-33 m s(-1)). EMGs of the important take-off muscles were recorded from one jumper. The dramatic decrease in take-off time found in all jumpers can be considered as the result of the influence of aerodynamic lift. The loss in impulse due to the shorter force production time with the same take-off force is compensated with the increase in lift force, res…
A simplified approach for load flow analysis in MV smart grids based on LV power measurements
2017
This paper presents a simplified approach for load flow analysis in medium voltage (MV) distribution networks. It is a power summation Backward/Forward (B/F) algorithm, based on measurements of active and reactive powers at low voltage (LV) side of MV/LV distribution substations. The proposed solution allows achieving good accuracy, computational efficiency and fast convergence. In order to verify the algorithm performances, simulation studies are carried out in the case of a real test system, i.e. the distribution grid of Favignana Island (Mediterranean Sea, Italy). The compatibility between simulations results and power measurements at the MV bus bars of the generating substation shows th…
Multi-objective optimization of nitinol stent design.
2017
Nitinol stents continuously experience loadings due to pulsatile pressure, thus a given stent design should possess an adequate fatigue strength and, at the same time, it should guarantee a sufficient vessel scaffolding. The present study proposes an optimization framework aiming at increasing the fatigue life reducing the maximum strut strain along the structure through a local modification of the strut profile.The adopted computational framework relies on nonlinear structural finite element analysis combined with a Multi Objective Genetic Algorithm, based on Kriging response surfaces. In particular, such an approach is used to investigate the design optimization of planar stent cell.The r…
A microcontroller-based portable electrocardiograph recorder.
2004
We describe a low cost portable Holler design that can be implemented with off-the-shelf components. The recorder is battery powered and includes a graphical display and keyboard. The recorder is capable of acquiring up to 48 hours of continuous electrocardiogram data at a sample rate of up to 250 Hz.
Simple equipment to measure biomechanical quantities of muscles and organs which includes a polarity-programmable peak detector
1982
Biomechanical measurements of muscles and organs require appropriate measuring equipment. As far as the static properties are concerned, the excursion of the bender bar of stress should be without force. The bender bar of force, however, ideally should not elongate under load. Because natural frequency is the most important boundary condition, the bender bar should be developed with this in mind. The developed bars imposed an insignificant preload to the muscle or to the organ. The small changes in resistance occurring in the resistance strain gauges affixed to the bars require the use of a highly stable amplifier. A new amplifier was accordingly developed based on the principle of an instr…
Modelling and dynamic simulation of hybrid moving bed biofilm reactors: model concepts and application to a pilot plant.
2011
In the recent years, there has been an increasing interest in the development of hybrid reactors, especially in the up-grading of existing activated sludge plants that are no longer able to comply with concentration limits established by regulatory agencies. In such systems the biomass grows both as suspended flocs and as biofilm. In this way, it is possible to obtain a higher biomass concentration in the reactor, but without any significant increase of the load to the final clarifier. The paper presents the setting-up of a dynamic mathematical model aimed at quantitatively describing the biokinetic processes occurring in a hybrid moving bed biofilm reactor (HMBBR), and, more in general, in…