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Measurement in Biomedicine |
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1-4 |
Titomir L.I., Mikhnev A.A., Trunov V.G., Aidu E.A.I.:
Practical
ECG Mapping with Few-lead Systems: A New Approach and Mathematical Modeling Abstract: Three versions of practical system for ECG mapping with extremely small
number of leads are considered. The chosen version is primarily intended for
noninvasive cardiac potential mapping on a spherical surface enclosing the heart
(imaging sphere). Using the simplified mathematical models of the chest as
bounded volume conductor and heart as bioelectric generator, it is shown that
the lead system with 12 unipolar leads situated rather conveniently for
practical investigations provides maps closely approximating the accurate maps
that could be obtained by multiple-lead mapping.
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5-10 |
Bajla I., Holländer I., Burg K.:
Improvement
of Electrophoretic Gel Image Analysis
MS PowerPoint
Presentation
Abstract: A novel methodology of DNA gel image analysis has been
proposed that is based on 2D image processing methods instead of previously used 1D Gaussian deconvolution. The
algorithms specifically tailored to band boundary detection and image intensity
homogeneity characterization have been developed. The proposed methodology
involves a modified type of user interaction.
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11-14 |
Courtney J., Burke D.P., de Paor A.M.:
Application
of Digital Image Processing to Marker-free Analysis of Human Gait Abstract: The
standard method of human gait analysis in use in gait laboratories today
invariably involves marker-based motion tracking systems. Although somewhat
effective, these methods require accurate placement of awkward external markers.
We report on an enhanced approach being researched and developed at the National
Rehabilitation Hospital, Dublin based on marker-free motion tracking
incorporating advanced digital image processing techniques.
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15-18 |
De Paor A., Burke D., O'Connor C.:
Application
of the Earth's Magnetic Field and Accelerometry to the Measurement of Net
Knee Extensor Torque Abstract: This
paper presents a new angle measurement and torque estimation scheme. The angle
of the shin is measured with a light, inexpensive two-axis magnetoresistive
bridge (Honeywell, HMC 1022),
sensing the swing of the leg through the Earth’s magnetic field. The plane of
swing is magnetic north-south. The transducer is currently hard-wired to a
computer, but it is planned to couple it via a miniature radio transmitter. A
single-axis accelerometer (Monitran, MTN/7000-5) is mounted on the leg, below
the knee at a specific distance, based on anthropomorphic data. This enables the
gravity nonlinearity in the equation of leg swing to be cancelled out,
linearises the observer and reduces its dynamical order.
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19-22 |
Burke D.P., de Paor A.M.:
Signal Prediction
Based on a Chaotic Attractor Model of the Electroencephalogram Abstract: This
paper presents results of a non-linear study of the human electroencephalogram
to establish the feasibility of extracting non-stationary information associated
with internal or external events and stimuli. By invoking chaotic time series
analysis techniques, short-term predictions are made on the attractor.
Comparisons with the real evolution of the EEG could in principle yield
stimulus-related information.
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23-26 |
Tyšler M., Turzová M., Szathmáry V.:
Assessment
of heart repolarization properties from body surface potential maps
Abstract: Use
of activation-recovery interval (ARI) in surface ECG leads as possible indicator
of changed repolarization in the underlying myocardium was studied. Model ECG
data representing normal and pathological myocardium repolarization were
simulated on surface of realistic inhomogeneous torso. Results of simulations
suggest that shortening
and prolongation of action potentials in anterior myocardial regions
representing more than 6% of the heart volume can be visible in surface ARI maps
while only prolongation in postero-lateral regions can be observed.
Reproducibility of ARI was checked on real measurements using 32 to 192 ECG
leads. Obtained ARI maps exhibited good intra-individual stability with
correlation 0.89 to 0.94. From the model and experimental results it has been
concluded that analysis of ARI may give some insight into the myocardium
repolarization and can help to recognize tissue with changed properties namely
in heart regions underlying the anterior chest. |
27-30 |
Rosík V., Tyšler M., Jurko Š., Rášo R., Turzová M.:
Portable
system for high resolution ECG mapping
Abstract: In
the paper a high resolution ECG mapping system based on personal computer or
notebook equipped with fast IEEE 1284 parallel port working in ECP mode is
introduced. Concept of the device enables high-resolution multi-channel ECG mapping
using up to 256 ECG leads. Concept of the device and description of electrical
and mechanical solution of portable 134-channel system is given. |
31-34 |
Rášo R., Rosík V., Tyšler M.:
Multichannel Measurement of human intestinal tract electrical acticity
Abstract: This
paper presents concept of a PC based multi-channel measuring system for
measurement, processing and displaying of signals of gastric electrical activity
in humans. It is designed for non-invasive measurements in clinical research and
practice. |
35-38 |
Štork M.:
The System
for Spiroergometric Data Measuring and Evaluation
Abstract: Exercise
testing today is used not only as a diagnostic tool, but also as a technique to
determine the physical performance
characteristic of a
patient. Heart
rate, pulmonary
ventilation, breathing
frequency and
blood pressure
are measured
during the
examination. Also
amount of
oxygen and carbon dioxide
are measured in patient breath. From these data, many of other standard
parameters are calculated by means of computer. In this paper, the systems for
automatic measuring and evaluating are described.
Application of
these systems
is possible
in work
medicine, sport
medicine and rehabilitation. |
39-42 |
Chwaleba A., Kwiatos K., Nitecki G.:
Portable
Microprocessor System for Tremor Signal Recording in Extrapyramidal Disease
Abstract: Tremor
constitutes one of the most important symptoms of neurological disorders.
However, its objective assessment is very difficult. The methods used for
objectivisation require application of such devices as piezoelectric detectors
or kymographs. The best results are achieved with the use of spectral
analysis. A simple measuring set consisting of accelerometer transducers and
multichannel A/D converter plugged in the ISA slot of a computer has been
designed in the Institute of Fundamental Electronics of Military University of
Technology, Warsaw, Poland. The equipment has been created to meet the
requirement of objective tremor measurement. The set includes specialised
software. |
43-46 |
Jakubowski J., Osowski S., Chwaleba A.:
Increasing
Effectiveness of Human Hand Tremor Separation Process by Using Higher-Order
Statistics
Abstract: The
paper presents an attempt to discriminate the most often observed three types of
human tremor with objective techniques by measuring the acceleration of the hand
and by calculating some characteristic features of these time series. Different
mathematical descriptions have been adopted in order to generate the features.
They have come from both second and higher-order statistics.
A simple neural classifier has enabled the recognition of these three
kinds of tremor with 3.6% error rate. |
47-50 |
Tarata M., Spaepen A., Puers R.:
The Accelerometer MMG Measurement Approach, in Monitoring the Muscular
Fatigue
Abstract: This
research aimed to appreciate whether the mechanomyogram (MMG) may be used to
monitor the muscle behaviour under fatiguing exercise. The electromyogram (EMG)
and MMG were simultaneously recorded from the Biceps and from the
Brachioradialis muscles, with surface electrodes - EMG, and accelerometer based
transducers – MMG, from sixteen subjects. The conclusions are consistent in
validating the use of the median frequency (MF) MMG to monitor the development
of the muscular fatigue in the isometric isotonic exercise, at 25 % maximal
voluntary contraction (MVC). The same as for the MF EMG, the MF MMG steadily
decreases from the very beginning of the exercise, down to exhaustion, again
demonstrating the central component of the muscular fatigue.
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51-54 |
Halámek J., Jurák P., Kára T., Souček M.:
Transfer Function and Biosignal Analysis
Abstract: On
the example of the baroreflex sensitivity the problems of transfer function in
biosignal analysis are presented. Mentioned is missing standardisation, big
variety of methods and supposed definitions, and missing optimization of the
diagnostic contribution.
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55-58 |
Ďaďo S., Mandys V., Šmíd R.:
Biomedical Shape Measurement for Neurotoxicity Testing
Abstract: In
this paper, we present the results of the new image-based morphometric approach
used to estimate toxic damage to the ganglia in alternative in vitro test. The
main part of this research is devoted to multiscale and multiresolution
approaches of biomedical planar shape description using continuous and discrete
wavelet transform.
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59-62 |
Roháľová M., Sykacek P., Koska M., Dorffner G.:
Detection of the EEG Artifacts by the Means of the (Extended) Kalman
Filter
Abstract: This
paper presents a new approach for detection of artifacts in sleep
electroencephalogram (EEG) recordings. The proposed approach is based on
Kalman filter. The idea of this approach consist in embedding the AR model
into the Kalman Filter which makes possible to use such KF AR (Kalman Filter AR) models for linear prediction of non-stationary signals. Such model
can be set up to detect and follow discrete dynamic changes of the signal. For
detection of the EEG artifacts we have exploited the evolution of the state
noise - increase in state noise indicate the dynamic change of the signal. The
evaluation of the results was done by the Receiver-Operator Characteristics
(ROC) curves - in terms of the specificity and the sensitivity. For 90% of the
specificity the best achieved value of the sensitivity using KF AR model was
33%. In order to achieve better results we have tried the following
modification: instead of the Kalman Filter we have used extended Kalman Filter
and instead of the AR model a neural network. The preliminary results look
promissing: for 90% of the specificity we have achieved 65% of the sensitivity.
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