Pavel Smrčka - Academia.edu (original) (raw)
Papers by Pavel Smrčka
Eurographics, 2008
We study series of fluorescent optical sections, i.e. three-dimensional (3D) biomedical images, c... more We study series of fluorescent optical sections, i.e. three-dimensional (3D) biomedical images, captured by a confocal laser scanning microscope (CLSM). Fluorescent image intensities of optical sections from deep layers of the specimen are often darker than intensities of sections from the top layers due to absorption and scattering of both excitation and fluorescent light. To solve this problem we apply a Markov Random Field (MRF) model-including an efficient deformation model for tracking structures within the 3D images-for computation of optical flow. We approach the corresponding optimization problem by the graph cuts. Image intensities of optical sections are recomputed according to the found optical flow, since the flow gives us evaluation of their proper brightness. Finally, the light attenuation with depth is compensated by matching accumulative histograms of optical sections of the original series with respect to optical sections improved by the optical flow. By this approach we obtain an algorithm that is less sensitive to changes of structures within series (especially to their enlargement and diminishing) than algorithms based purely on histogram matching, warping or equalization.
The aim of this study is to determine the readiness of air defense cadets for inherently stressfu... more The aim of this study is to determine the readiness of air defense cadets for inherently stressful long-term air traffic control (ATC). Although the origin of stress is psychological, it affects physiological functions like heart rate (HR) and heart rate variability (HRV). HR and HRV data were obtained from four air traffic controllers (ATCs) recording the data over a course of 4 hours. The task of the ATCs was to record information about a flight code, duration of the flight in the border zone, as well as information whether the aircraft was flying in or out of the Czech Republic's airspace. The results showed statistically significant interindividual differences in the observed HRV variables during low and high workload. The results can help evaluate the stress and readiness of cadets / operators of complex systems in air defense.
This paper aims to evaluate psychological load assessment methods in air defense members. The stu... more This paper aims to evaluate psychological load assessment methods in air defense members. The study is based on physiological data monitoring and compares this method with traditional questionnaire evaluation methods. Measurement using a biotelemetric system was conducted while training in flight simulators. A total of 28 subjects/soldiers were divided into seven four-member teams consisting of two pilots, an air traffic controller and a member of ground support. Physiological data was collected and monitored for all subjects during a mission flight operation. Calculations of the R-R interval length and respiratory rate were performed for all soldiers involved. Statistical analysis, i.e. the calculation of the median, maximum, minimum, first quartile and third quartile were used for physiological data presentation and the quantitative evaluation of mental stress. These results were then compared with results showing the subjective degree of psychological stress load, as determined by the questionnaire evaluation method. A simple rating scales repeatedly evaluated by individual subjects were used to determine their subjective level of mental stress before and after individual phases of the training. The data for takeoff, landing, horizontal flight and fall were evaluated and compared. Then the results for both evaluation approaches (physiological data measurement and questionnaire-based subjective evaluation) were compared. Since the normal data distribution was not shown, statistical evaluation was conducted through non-parametric tests. Based on the calculated values of the physiological parameters compared with the determined value of the questionnaire method’s rating scale, it was found that with increasing mental load determined by the subjective evaluation method, the length of the R-R interval decreased and the respiratory rate increased. These conclusions were consistent for different flight phases and within the groups of pilots, air traffic controllers and ground support members.
PubMed, Jun 1, 2013
Nowadays, bipedal walking is undergoing extensive study. Several methods can be used in physiothe... more Nowadays, bipedal walking is undergoing extensive study. Several methods can be used in physiotherapeutic research for identifying defects in bipedal walking as a result of pathology of the musculoskeletal or nervous system. Our work focuses on studying asymmetry of walking based on synchronized bilateral knee-knee cyclograms. Participants presenting with peroneal nerve palsy and foot drop were included in the study. The bilateral cyclograms, also called angle-angle diagrams, were created to quantify gait asymmetry before and immediately after application of a brace. In order to quantify the asymmetry of human walking, we have described and tested the application of the method based on the inclination angle of the synchronized bilateral cyclograms. The symmetry index (SI) was used as a comparative method to evaluate the symmetry of bipedal walking. The method based on the orientation of the cyclograms can be used as an additional method for determining the gait asymmetry. The new technique has never been applied before to study the gait asymmetry in patients with peroneal nerve palsy or patients with leg brace.
Advances in intelligent systems and computing, Aug 28, 2019
This article aims to describe methods determining the intensity of movement activity while using ... more This article aims to describe methods determining the intensity of movement activity while using a smart orthosis for the upper limbs. The methods proposed can be applied both in clinical practice and the home environment. Kinematics data was quantified by evaluation methods of time domain data. These can determine the integral of the absolute value of total acceleration, kinetic energy of the segment in translational motion, mechanical power during a segment motion, and a geometric sum of three partial accelerations of threedimensional motion. The method's applicability was tested by a comparison of the forearm and upper arm movement while the subjects performed various activities. Following on from the goal of method tested, the team applied it to a set of cyclic and non-cyclic movements commonly performed in a home environment. The study was conducted on twenty healthy participants. Four gyro-accelerometers to record the upper limb movement were attached to the subject's forearms and upper arms. The results of the calculated values for the proposed parameters revealed statistically significant differences depending on the physical activities monitored. The results also showed that the calculated values for the forearm and upper arm parameters correlate significantly. This is due to the concurrent similar movement of the segments with accelerometers during a particular physical activity. The proposed methods have proven their applicability for monitoring the intensity of motion during rehabilitation.
IFMBE proceedings, May 30, 2018
Many complex situations can be induced to the members of air forces during training on simulators... more Many complex situations can be induced to the members of air forces during training on simulators, which may result in mentally vigorous situations or even overload. The aim of the paper is to describe the current state and our contribution to development of systems for measurement of the physiological data of basic member of air force including mission commander, pilots, air traffic controllers and ground support staff. The reason for physiological data monitoring is to test the possibility of usage them to estimate the physical and psychological state of the team members. The base for the design of physiological data monitoring was the FlexiGuar system, originally developed at the FBMI CTU. The core of simulators for training of military personnel in aviation was Lockheed Martin’s Prepar3D simulation software. Two airplane cockpits were used as simulators for training of two pilots, air traffic control simulator, i.e. a control tower simulator, and an airport ground station for the preparation of aviation ground staff. The proposed systems are used for simultaneous measurement of the working performance and physiological data of members of the four‐member team during their training. The physiological data, heart rate, body temperature, movement activity and perspiration intensity, are transferred to the commander visualization unit for further evaluation. Designed systems and methods could help to monitor, on the base of physiological data and data from simulators, the stress load of team members.
From the second half of the 1990s, thanks to more affordable and more powerful technology and sys... more From the second half of the 1990s, thanks to more affordable and more powerful technology and systems for recording based on miniaturized sensors, we can observe a more intensive development of a system that monitors the physical and psychological conditions of soldiers. Systems for measuring of physical and medical data for the diagnostics of physical and psychological state has significantly spread. This study, however, examines the current technologies and usage of the wearable monitoring systems in military. The article can serve as a guide for choosing suitable and affordable systems of quantitative evaluation of physical and psychological conditions of soldiers. In addition, the innovative telemetry monitoring system (FlexiGuard system) composed of appropriate sensors is introduced. Based on previous researches and tests, FlexiGuard system and its sensors are recommended for use in military practice.
IFMBE proceedings, May 30, 2018
The aim of article is to present new method for evaluating the postural stability using oscillati... more The aim of article is to present new method for evaluating the postural stability using oscillating platform. Proposed methods are alternative to basic methods which are usually parts of the commercial posturography systems. The methods for calculating the postural parameters have been designed in order to objectively quantify and classify the ability of postural stabilization on a standardized oscillatory platform, and determine differences in the postural stabilization of motor function in healthy people and in people with postural instability. The Posturomed (Haider Bioswing GmbH) and biaxial accelerometer sensor were used for measurement the body acceleration during single leg stance provocation test. The postural somatooscilogram has been defined, which shows accelerations of platform, in horizontal plane in both anteroposterior and mediolateral directions over time. Two parameters, Average Damping Coefficient (ADC) and Average Coefficient of Damped Energy (ACDE), were used to evaluate postural stability. The proposed method was implemented in MatLab sw. Patients with postural disorders and control group of healthy subjects were measured. Statistically significant differences have been observed in postural stability between independent postural stable group and postural unstable groups. Based on the findings, we can say that the presented method allows a complex analysis of the single leg stance in patients with postural balance disorders in clinical practice.
IFMBE proceedings, May 30, 2018
The aim of the article is to introduce new evaluation methodology to determine operational prepar... more The aim of the article is to introduce new evaluation methodology to determine operational preparedness of air defense staff based on measurement of physiological data. The individuals working with air defense systems are under very high level of stress and long‐term monotone air picture observation workload during the mission. We designed an experiment and a method of measuring the biomedical signals for monitoring the actual operator condition during long‐term work on air picture simulator that shows real‐time aircraft flight information. Long‐term monitoring and recording of potential airborne targets in the area of interest to which operators are subjected is accompanied by monitoring the physiological data such as heart rate, body temperature, movement activity and perspiration intensity of operators. The proposed methodology and measurements were tested on four air defense system operators of the Army of the Czech Republic. Operators took part in a 4‐h intensive measurement without any break and their training was evaluated. Designed methods could help to monitor, on the base of physiological data and data from simulators, the stress load level and operational preparedness.
Atrial fibrillation ranks among the most common heart rhythm disorders. Considering the lack of a... more Atrial fibrillation ranks among the most common heart rhythm disorders. Considering the lack of any trusted method capable of foreseeing possible recurrence of atrial fibrillation after it has been terminated, nonlinear analyses of beat-tobeat heart rate variability demonstrate promising potential. This work focuses on verifying the capability of the nonlinear methods to differentiate patients with early recurrence of atrial fibrillation from those with stable normal sinus rhythm after cardioversion. Both patients groups underwent the active-standing test involving ECG measurement. Recurrence quantification analysis was used to evaluate sequences of intervals between two consecutive heart beats. The data were derived from body surface ECG signal. The results selected those parameters capable of identification of patient groups during the initial phase of the active-standing test prior to cardioversion.
Biomedical Signal Processing and Control, Feb 1, 2018
This work focuses on the novelty of applying a 3-D postural analysis on the cerebellar disorders ... more This work focuses on the novelty of applying a 3-D postural analysis on the cerebellar disorders diagnosis and on introduction of an alternative to recent methods of quantifying the human postural stability during quiet stance, which uses a three-axis accelerometer. It introduces an advantage in the form of an ability to evaluate a complex three-dimensional (3-D) movement, as opposed to a major limitation of todayís alternatives that evaluate only two coordinates in space. 3-D data (anterior-posterior, superior-inferior, and medio-lateral accelerations of a patientís trunk) were obtained using a three-axis accelerometer (Xsens Mtx), enabling us to evaluate 3-D translational body movements on the basis of the average velocity (AV) of the point and the total length (TL) of the 3-dimensional trajectory. Then a pathological balance control has been identified from the 3-D plot of the three trajectories. The data were obtained from patients suffering from the progressive cerebellar ataxia as well as from healthy participants and were analyzed statistically. The analysis revealed several significant differences between the AVs and TLs of the patients versus the healthy participants.
Advances in intelligent systems and computing, Aug 28, 2019
The methods described provide for quantitative evaluation of skeletal muscles’ passive resistance... more The methods described provide for quantitative evaluation of skeletal muscles’ passive resistance, also known as muscle stiffness, muscle myotonia or spasticity. They are employed in the quantitative evaluation of muscle groups responsible for angular movements in the elbow joint. The methods, along with the manually actuated dynamometer, represent an alternative to current evaluation methods which are considered inaccurate and subjective. The function of the electronic dynamometer subsystem is to measure angle and torque in the elbow joint. Stiffness can be evaluated by a graph of the torque moment and joint angle in mutual dependence. Since the curve of dependence demonstrates a relation between the torque moment and joint angle is composed of three parts (small, mean, and high angles), three polynomial equations for three regression lines must be calculated. This means that for three regression lines, three values of joint stiffness are obtained. Angular velocity of the rotational movement in a joint is the result of movement affected by a manually controlled lever of dynamometer. No statistically significant difference in joint stiffness values was identified, when comparing values for individual joint stiffness across three different groups of angular velocities; however, when the same comparison was made for small, mean and high angles, a statistically significant difference was identified for all three angular velocities used. The experiments with healthy subjects confirmed, that the torsional moment is dependent on the elbow angle, not on the velocity of the movement. Finding a correlation between a passive moment of force and kinematic angular parameters allows for the study of a complex movement in a joint.
IFMBE proceedings, May 30, 2018
The article presents measurement methodology and systems for measuring and evaluating the respons... more The article presents measurement methodology and systems for measuring and evaluating the response of patients suffering from type I diabetes to stress burden. The proposed methodology and systems have been developed to recognize the effects of strain on patients’ reaction time and their work performance. Stress burden was measured by a multi-sensory monitoring system designed for this purpose. The methods used were based on monitoring physiological stress symptoms by measuring pulse rate, respiratory rate, temperature, galvanic skin resistance, and electrical activity of muscles. It was suggested to monitor the measured parameters in waveform, from initiation of stress stimuli, throughout the period of growth, and up to the point of decline. The research was conducted under the supervision of psychologists, and the proposed methodology for measuring stress burden and its impact on physiological functions of type I diabetics involved a group of patients and a control group of healthy subjects. The proposed measurement methodology would be beneficial not only in the design of systems for detecting mental stress, but also in the treatment of patients suffering from diabetes and the assessment of their physical/mental state while performing demanding work tasks.
![Research paper thumbnail of [PP.16.13] Home Blood Pressure Telemonitoring Offers More Reliable Values and Information About Irregular Heartbeat Episodes](https://attachments.academia-assets.com/110711363/thumbnails/1.jpg)
](Journal of Hypertension, Sep 1, 2017
Objective: BP values reported by the patient from home BP monitoring (HBPM) may not always be rel... more Objective: BP values reported by the patient from home BP monitoring (HBPM) may not always be reliable due to intentional or unintentional transcription errors. However, direct HBP telemonitoring can eliminate such mistakes. The detection of asymptomatic atrial fi brillation (AF) (or irregular heartbeat rhythm-IHR) by new technologies including BP machines with AF detection algorithms has not yet been formally evaluated against an established method.
Springer eBooks, 2011
In this work we deal with acquiring and consecutive processing and last but not least with data a... more In this work we deal with acquiring and consecutive processing and last but not least with data analysis, acquired at the Charles University, Faculty of Science in real experiments. The data consists of psychological factors computed from psychological questionnaires helping to determinate level of dominance or submissiveness. The second part of data consists of electrophysiological parameters acquired in double tests, including stressful part and relaxation part. We discovered a correlation between psychological factors and few parameters of HRV analysis. The usage of psychological factors helps to better classify the stress part.
IFMBE proceedings, May 30, 2018
In the article, we describe a design of a new system which provides means to quantitatively asses... more In the article, we describe a design of a new system which provides means to quantitatively assess passive resistance of skeletal muscles, also termed muscle spasticity. New design is focused on the measurement of muscle groups which are responsible for movement of elbow joint. The semiportable system is an alternative to expensive motorized isokinetic dynamometers. System is manually actuated dynamometer. The electronic subsystem of the system is used to measure angular velocity and torque in the elbow joint. An incremental encoder is used for the measurement of angular velocity. The angular velocity of the rotational movement in a joint is a result of movement effected by manually controlled lever. The lever is controlled by a physician. During the angular movement of the upper limb segments, the elbow joint torque is measured by a strain gauge subsystem. The output from the system is a graphic dependence between the angular velocity and the torque, which is used to evaluate spasticity. The dependence between the passive moment of force and kinematic angular parameters allows us to study complex motion and force possibilities of the joint. The designed system could be useable and widely applicable in clinical practice, as well as research of diseases and treatment of musculoskeletal system.
Komunikácie, Feb 28, 2015
The article summarizes preliminary results of the research and development of a system focused on... more The article summarizes preliminary results of the research and development of a system focused on enhancing the safety of teams participating in the integrated rescue system managing extraordinary events or crisis situations (fire, mass disaster, release of harmful industrial substances), and on the support in the course of training. Individual partial technical solutions are mentioned, which should lead to providing automatized telemetric monitoring equipment in a more resistant form making it possible to recognize the nature and intensity of the motion, including the determination of the topical and total energy outputs, monitoring of environmental parameters (temperature, smoke, etc.) and back analysis of the intervention course or training in real time, and the monitoring of health-physiological parameters and signalling risk conditions (physical exhaustion, stress, overheating, etc.) under extreme measures.
Due to more affordable and powerful physiological data monitoring systems becoming available, pil... more Due to more affordable and powerful physiological data monitoring systems becoming available, pilots’ current physical and psychological status can be monitored more intensively. Contactless monitoring is needed for several reasons; the first concerns traditional sensors and their influence when placed in contact with the body of the measured person. Such sensors can have a negative effect upon the comfort or work performance of a pilot. The second important reason why contactless monitoring methods are preferred over other methods is legislative limitations. Another disadvantage emerges when health measurements and signals are adversely affected by the state of environment. This study examines the current technologies, design and application of non-contact systems as applied in military pilot monitoring. The three systems selected and tested are: ballistocardiography, video motion capture and thermography. The article serves as an evaluation guide for the most suitable and affordable non-contact monitoring systems available, when facing the dilemma of evaluating the quantitative physical and psychological conditions of military pilots. In addition, the article introduces an innovative non-contact telemetry monitoring system composed of appropriate subsystems. Based on previous research and tests, non-contact systems are strongly recommended for military pilot training.
IFMBE proceedings, May 30, 2018
Movement problems of the upper limb are a common consequence of many diseases and can drastically... more Movement problems of the upper limb are a common consequence of many diseases and can drastically affect the daily life impairing normal activities. To regain motor function and muscle power is necessary to treat these diseases with an intense physical therapy. The smart orthosis is an effective and modern method used in the process of muscle rehabilitation. We propose a design of motorized orthosis subsystems for the upper limbs. The orthosis is a motor assist robotic system that, with the help of actuators, will allow the movement of selected parts of the upper limb. The main point is to offer a reliable low weighted exoskeleton with selected sensors to move and control the upper limbs covering 6 motions: shoulder adduction and abduction, shoulder flexion and extension and elbow flexion and extension. The device is a junction of a hard orthosis with a soft orthosis in order to perform passive physical therapist exercises in clinical practice. The actuation is made by Bowden cables connected in one end to the limb and another to a stepper motor located at a backpack carried by the patient decreasing the apparatus weight substantially. The project also includes a selection of sensors comprising accelerometers, strain gages, thermostats, oximeters, that can provide the necessary information to move the limbs quantifying the muscle activity and physical condition through time. Also, a cooling subsystem based on Peltier thermoelectric modules was implemented to control the muscle temperature in case of an inflammatory reaction. The design was certified by kinematic and structural strength simulation using SolidWorks software.
Lecture Notes in Computer Science, 2018
A military pilot fulfilling his mission can often be caught in precarious situations and put unde... more A military pilot fulfilling his mission can often be caught in precarious situations and put under extreme strain. The aim of this article is to describe the current development of systems and methods for measuring and modelling military pilot’s behavior. The first part of this paper outlines the systems and methods for measuring and evaluation of physical and medical data needed to describe the condition and behavior of military pilots quantitatively. The second part focuses on an expert system approach to modelling military pilot behavior. The authors demonstrate, how the modules of the system were created and how measurements and tests were performed. The research findings outline the new expert system modelling military pilot’s behavior. Moreover, subsystems and sensors applied in the cockpit so that the system as a whole can support the pilot, are described. The complete system is able to determine the pilot’s stress load, along with physical and visual load levels. Based on this knowledge, it is possible to determine whether the pilot needs the support of the automatic flight control system. This system can be also be used in the flight control system and can increase battle effectiveness of the deployed aircrafts.
Eurographics, 2008
We study series of fluorescent optical sections, i.e. three-dimensional (3D) biomedical images, c... more We study series of fluorescent optical sections, i.e. three-dimensional (3D) biomedical images, captured by a confocal laser scanning microscope (CLSM). Fluorescent image intensities of optical sections from deep layers of the specimen are often darker than intensities of sections from the top layers due to absorption and scattering of both excitation and fluorescent light. To solve this problem we apply a Markov Random Field (MRF) model-including an efficient deformation model for tracking structures within the 3D images-for computation of optical flow. We approach the corresponding optimization problem by the graph cuts. Image intensities of optical sections are recomputed according to the found optical flow, since the flow gives us evaluation of their proper brightness. Finally, the light attenuation with depth is compensated by matching accumulative histograms of optical sections of the original series with respect to optical sections improved by the optical flow. By this approach we obtain an algorithm that is less sensitive to changes of structures within series (especially to their enlargement and diminishing) than algorithms based purely on histogram matching, warping or equalization.
The aim of this study is to determine the readiness of air defense cadets for inherently stressfu... more The aim of this study is to determine the readiness of air defense cadets for inherently stressful long-term air traffic control (ATC). Although the origin of stress is psychological, it affects physiological functions like heart rate (HR) and heart rate variability (HRV). HR and HRV data were obtained from four air traffic controllers (ATCs) recording the data over a course of 4 hours. The task of the ATCs was to record information about a flight code, duration of the flight in the border zone, as well as information whether the aircraft was flying in or out of the Czech Republic's airspace. The results showed statistically significant interindividual differences in the observed HRV variables during low and high workload. The results can help evaluate the stress and readiness of cadets / operators of complex systems in air defense.
This paper aims to evaluate psychological load assessment methods in air defense members. The stu... more This paper aims to evaluate psychological load assessment methods in air defense members. The study is based on physiological data monitoring and compares this method with traditional questionnaire evaluation methods. Measurement using a biotelemetric system was conducted while training in flight simulators. A total of 28 subjects/soldiers were divided into seven four-member teams consisting of two pilots, an air traffic controller and a member of ground support. Physiological data was collected and monitored for all subjects during a mission flight operation. Calculations of the R-R interval length and respiratory rate were performed for all soldiers involved. Statistical analysis, i.e. the calculation of the median, maximum, minimum, first quartile and third quartile were used for physiological data presentation and the quantitative evaluation of mental stress. These results were then compared with results showing the subjective degree of psychological stress load, as determined by the questionnaire evaluation method. A simple rating scales repeatedly evaluated by individual subjects were used to determine their subjective level of mental stress before and after individual phases of the training. The data for takeoff, landing, horizontal flight and fall were evaluated and compared. Then the results for both evaluation approaches (physiological data measurement and questionnaire-based subjective evaluation) were compared. Since the normal data distribution was not shown, statistical evaluation was conducted through non-parametric tests. Based on the calculated values of the physiological parameters compared with the determined value of the questionnaire method’s rating scale, it was found that with increasing mental load determined by the subjective evaluation method, the length of the R-R interval decreased and the respiratory rate increased. These conclusions were consistent for different flight phases and within the groups of pilots, air traffic controllers and ground support members.
PubMed, Jun 1, 2013
Nowadays, bipedal walking is undergoing extensive study. Several methods can be used in physiothe... more Nowadays, bipedal walking is undergoing extensive study. Several methods can be used in physiotherapeutic research for identifying defects in bipedal walking as a result of pathology of the musculoskeletal or nervous system. Our work focuses on studying asymmetry of walking based on synchronized bilateral knee-knee cyclograms. Participants presenting with peroneal nerve palsy and foot drop were included in the study. The bilateral cyclograms, also called angle-angle diagrams, were created to quantify gait asymmetry before and immediately after application of a brace. In order to quantify the asymmetry of human walking, we have described and tested the application of the method based on the inclination angle of the synchronized bilateral cyclograms. The symmetry index (SI) was used as a comparative method to evaluate the symmetry of bipedal walking. The method based on the orientation of the cyclograms can be used as an additional method for determining the gait asymmetry. The new technique has never been applied before to study the gait asymmetry in patients with peroneal nerve palsy or patients with leg brace.
Advances in intelligent systems and computing, Aug 28, 2019
This article aims to describe methods determining the intensity of movement activity while using ... more This article aims to describe methods determining the intensity of movement activity while using a smart orthosis for the upper limbs. The methods proposed can be applied both in clinical practice and the home environment. Kinematics data was quantified by evaluation methods of time domain data. These can determine the integral of the absolute value of total acceleration, kinetic energy of the segment in translational motion, mechanical power during a segment motion, and a geometric sum of three partial accelerations of threedimensional motion. The method's applicability was tested by a comparison of the forearm and upper arm movement while the subjects performed various activities. Following on from the goal of method tested, the team applied it to a set of cyclic and non-cyclic movements commonly performed in a home environment. The study was conducted on twenty healthy participants. Four gyro-accelerometers to record the upper limb movement were attached to the subject's forearms and upper arms. The results of the calculated values for the proposed parameters revealed statistically significant differences depending on the physical activities monitored. The results also showed that the calculated values for the forearm and upper arm parameters correlate significantly. This is due to the concurrent similar movement of the segments with accelerometers during a particular physical activity. The proposed methods have proven their applicability for monitoring the intensity of motion during rehabilitation.
IFMBE proceedings, May 30, 2018
Many complex situations can be induced to the members of air forces during training on simulators... more Many complex situations can be induced to the members of air forces during training on simulators, which may result in mentally vigorous situations or even overload. The aim of the paper is to describe the current state and our contribution to development of systems for measurement of the physiological data of basic member of air force including mission commander, pilots, air traffic controllers and ground support staff. The reason for physiological data monitoring is to test the possibility of usage them to estimate the physical and psychological state of the team members. The base for the design of physiological data monitoring was the FlexiGuar system, originally developed at the FBMI CTU. The core of simulators for training of military personnel in aviation was Lockheed Martin’s Prepar3D simulation software. Two airplane cockpits were used as simulators for training of two pilots, air traffic control simulator, i.e. a control tower simulator, and an airport ground station for the preparation of aviation ground staff. The proposed systems are used for simultaneous measurement of the working performance and physiological data of members of the four‐member team during their training. The physiological data, heart rate, body temperature, movement activity and perspiration intensity, are transferred to the commander visualization unit for further evaluation. Designed systems and methods could help to monitor, on the base of physiological data and data from simulators, the stress load of team members.
From the second half of the 1990s, thanks to more affordable and more powerful technology and sys... more From the second half of the 1990s, thanks to more affordable and more powerful technology and systems for recording based on miniaturized sensors, we can observe a more intensive development of a system that monitors the physical and psychological conditions of soldiers. Systems for measuring of physical and medical data for the diagnostics of physical and psychological state has significantly spread. This study, however, examines the current technologies and usage of the wearable monitoring systems in military. The article can serve as a guide for choosing suitable and affordable systems of quantitative evaluation of physical and psychological conditions of soldiers. In addition, the innovative telemetry monitoring system (FlexiGuard system) composed of appropriate sensors is introduced. Based on previous researches and tests, FlexiGuard system and its sensors are recommended for use in military practice.
IFMBE proceedings, May 30, 2018
The aim of article is to present new method for evaluating the postural stability using oscillati... more The aim of article is to present new method for evaluating the postural stability using oscillating platform. Proposed methods are alternative to basic methods which are usually parts of the commercial posturography systems. The methods for calculating the postural parameters have been designed in order to objectively quantify and classify the ability of postural stabilization on a standardized oscillatory platform, and determine differences in the postural stabilization of motor function in healthy people and in people with postural instability. The Posturomed (Haider Bioswing GmbH) and biaxial accelerometer sensor were used for measurement the body acceleration during single leg stance provocation test. The postural somatooscilogram has been defined, which shows accelerations of platform, in horizontal plane in both anteroposterior and mediolateral directions over time. Two parameters, Average Damping Coefficient (ADC) and Average Coefficient of Damped Energy (ACDE), were used to evaluate postural stability. The proposed method was implemented in MatLab sw. Patients with postural disorders and control group of healthy subjects were measured. Statistically significant differences have been observed in postural stability between independent postural stable group and postural unstable groups. Based on the findings, we can say that the presented method allows a complex analysis of the single leg stance in patients with postural balance disorders in clinical practice.
IFMBE proceedings, May 30, 2018
The aim of the article is to introduce new evaluation methodology to determine operational prepar... more The aim of the article is to introduce new evaluation methodology to determine operational preparedness of air defense staff based on measurement of physiological data. The individuals working with air defense systems are under very high level of stress and long‐term monotone air picture observation workload during the mission. We designed an experiment and a method of measuring the biomedical signals for monitoring the actual operator condition during long‐term work on air picture simulator that shows real‐time aircraft flight information. Long‐term monitoring and recording of potential airborne targets in the area of interest to which operators are subjected is accompanied by monitoring the physiological data such as heart rate, body temperature, movement activity and perspiration intensity of operators. The proposed methodology and measurements were tested on four air defense system operators of the Army of the Czech Republic. Operators took part in a 4‐h intensive measurement without any break and their training was evaluated. Designed methods could help to monitor, on the base of physiological data and data from simulators, the stress load level and operational preparedness.
Atrial fibrillation ranks among the most common heart rhythm disorders. Considering the lack of a... more Atrial fibrillation ranks among the most common heart rhythm disorders. Considering the lack of any trusted method capable of foreseeing possible recurrence of atrial fibrillation after it has been terminated, nonlinear analyses of beat-tobeat heart rate variability demonstrate promising potential. This work focuses on verifying the capability of the nonlinear methods to differentiate patients with early recurrence of atrial fibrillation from those with stable normal sinus rhythm after cardioversion. Both patients groups underwent the active-standing test involving ECG measurement. Recurrence quantification analysis was used to evaluate sequences of intervals between two consecutive heart beats. The data were derived from body surface ECG signal. The results selected those parameters capable of identification of patient groups during the initial phase of the active-standing test prior to cardioversion.
Biomedical Signal Processing and Control, Feb 1, 2018
This work focuses on the novelty of applying a 3-D postural analysis on the cerebellar disorders ... more This work focuses on the novelty of applying a 3-D postural analysis on the cerebellar disorders diagnosis and on introduction of an alternative to recent methods of quantifying the human postural stability during quiet stance, which uses a three-axis accelerometer. It introduces an advantage in the form of an ability to evaluate a complex three-dimensional (3-D) movement, as opposed to a major limitation of todayís alternatives that evaluate only two coordinates in space. 3-D data (anterior-posterior, superior-inferior, and medio-lateral accelerations of a patientís trunk) were obtained using a three-axis accelerometer (Xsens Mtx), enabling us to evaluate 3-D translational body movements on the basis of the average velocity (AV) of the point and the total length (TL) of the 3-dimensional trajectory. Then a pathological balance control has been identified from the 3-D plot of the three trajectories. The data were obtained from patients suffering from the progressive cerebellar ataxia as well as from healthy participants and were analyzed statistically. The analysis revealed several significant differences between the AVs and TLs of the patients versus the healthy participants.
Advances in intelligent systems and computing, Aug 28, 2019
The methods described provide for quantitative evaluation of skeletal muscles’ passive resistance... more The methods described provide for quantitative evaluation of skeletal muscles’ passive resistance, also known as muscle stiffness, muscle myotonia or spasticity. They are employed in the quantitative evaluation of muscle groups responsible for angular movements in the elbow joint. The methods, along with the manually actuated dynamometer, represent an alternative to current evaluation methods which are considered inaccurate and subjective. The function of the electronic dynamometer subsystem is to measure angle and torque in the elbow joint. Stiffness can be evaluated by a graph of the torque moment and joint angle in mutual dependence. Since the curve of dependence demonstrates a relation between the torque moment and joint angle is composed of three parts (small, mean, and high angles), three polynomial equations for three regression lines must be calculated. This means that for three regression lines, three values of joint stiffness are obtained. Angular velocity of the rotational movement in a joint is the result of movement affected by a manually controlled lever of dynamometer. No statistically significant difference in joint stiffness values was identified, when comparing values for individual joint stiffness across three different groups of angular velocities; however, when the same comparison was made for small, mean and high angles, a statistically significant difference was identified for all three angular velocities used. The experiments with healthy subjects confirmed, that the torsional moment is dependent on the elbow angle, not on the velocity of the movement. Finding a correlation between a passive moment of force and kinematic angular parameters allows for the study of a complex movement in a joint.
IFMBE proceedings, May 30, 2018
The article presents measurement methodology and systems for measuring and evaluating the respons... more The article presents measurement methodology and systems for measuring and evaluating the response of patients suffering from type I diabetes to stress burden. The proposed methodology and systems have been developed to recognize the effects of strain on patients’ reaction time and their work performance. Stress burden was measured by a multi-sensory monitoring system designed for this purpose. The methods used were based on monitoring physiological stress symptoms by measuring pulse rate, respiratory rate, temperature, galvanic skin resistance, and electrical activity of muscles. It was suggested to monitor the measured parameters in waveform, from initiation of stress stimuli, throughout the period of growth, and up to the point of decline. The research was conducted under the supervision of psychologists, and the proposed methodology for measuring stress burden and its impact on physiological functions of type I diabetics involved a group of patients and a control group of healthy subjects. The proposed measurement methodology would be beneficial not only in the design of systems for detecting mental stress, but also in the treatment of patients suffering from diabetes and the assessment of their physical/mental state while performing demanding work tasks.
Journal of Hypertension, Sep 1, 2017
Objective: BP values reported by the patient from home BP monitoring (HBPM) may not always be rel... more Objective: BP values reported by the patient from home BP monitoring (HBPM) may not always be reliable due to intentional or unintentional transcription errors. However, direct HBP telemonitoring can eliminate such mistakes. The detection of asymptomatic atrial fi brillation (AF) (or irregular heartbeat rhythm-IHR) by new technologies including BP machines with AF detection algorithms has not yet been formally evaluated against an established method.
Springer eBooks, 2011
In this work we deal with acquiring and consecutive processing and last but not least with data a... more In this work we deal with acquiring and consecutive processing and last but not least with data analysis, acquired at the Charles University, Faculty of Science in real experiments. The data consists of psychological factors computed from psychological questionnaires helping to determinate level of dominance or submissiveness. The second part of data consists of electrophysiological parameters acquired in double tests, including stressful part and relaxation part. We discovered a correlation between psychological factors and few parameters of HRV analysis. The usage of psychological factors helps to better classify the stress part.
IFMBE proceedings, May 30, 2018
In the article, we describe a design of a new system which provides means to quantitatively asses... more In the article, we describe a design of a new system which provides means to quantitatively assess passive resistance of skeletal muscles, also termed muscle spasticity. New design is focused on the measurement of muscle groups which are responsible for movement of elbow joint. The semiportable system is an alternative to expensive motorized isokinetic dynamometers. System is manually actuated dynamometer. The electronic subsystem of the system is used to measure angular velocity and torque in the elbow joint. An incremental encoder is used for the measurement of angular velocity. The angular velocity of the rotational movement in a joint is a result of movement effected by manually controlled lever. The lever is controlled by a physician. During the angular movement of the upper limb segments, the elbow joint torque is measured by a strain gauge subsystem. The output from the system is a graphic dependence between the angular velocity and the torque, which is used to evaluate spasticity. The dependence between the passive moment of force and kinematic angular parameters allows us to study complex motion and force possibilities of the joint. The designed system could be useable and widely applicable in clinical practice, as well as research of diseases and treatment of musculoskeletal system.
Komunikácie, Feb 28, 2015
The article summarizes preliminary results of the research and development of a system focused on... more The article summarizes preliminary results of the research and development of a system focused on enhancing the safety of teams participating in the integrated rescue system managing extraordinary events or crisis situations (fire, mass disaster, release of harmful industrial substances), and on the support in the course of training. Individual partial technical solutions are mentioned, which should lead to providing automatized telemetric monitoring equipment in a more resistant form making it possible to recognize the nature and intensity of the motion, including the determination of the topical and total energy outputs, monitoring of environmental parameters (temperature, smoke, etc.) and back analysis of the intervention course or training in real time, and the monitoring of health-physiological parameters and signalling risk conditions (physical exhaustion, stress, overheating, etc.) under extreme measures.
Due to more affordable and powerful physiological data monitoring systems becoming available, pil... more Due to more affordable and powerful physiological data monitoring systems becoming available, pilots’ current physical and psychological status can be monitored more intensively. Contactless monitoring is needed for several reasons; the first concerns traditional sensors and their influence when placed in contact with the body of the measured person. Such sensors can have a negative effect upon the comfort or work performance of a pilot. The second important reason why contactless monitoring methods are preferred over other methods is legislative limitations. Another disadvantage emerges when health measurements and signals are adversely affected by the state of environment. This study examines the current technologies, design and application of non-contact systems as applied in military pilot monitoring. The three systems selected and tested are: ballistocardiography, video motion capture and thermography. The article serves as an evaluation guide for the most suitable and affordable non-contact monitoring systems available, when facing the dilemma of evaluating the quantitative physical and psychological conditions of military pilots. In addition, the article introduces an innovative non-contact telemetry monitoring system composed of appropriate subsystems. Based on previous research and tests, non-contact systems are strongly recommended for military pilot training.
IFMBE proceedings, May 30, 2018
Movement problems of the upper limb are a common consequence of many diseases and can drastically... more Movement problems of the upper limb are a common consequence of many diseases and can drastically affect the daily life impairing normal activities. To regain motor function and muscle power is necessary to treat these diseases with an intense physical therapy. The smart orthosis is an effective and modern method used in the process of muscle rehabilitation. We propose a design of motorized orthosis subsystems for the upper limbs. The orthosis is a motor assist robotic system that, with the help of actuators, will allow the movement of selected parts of the upper limb. The main point is to offer a reliable low weighted exoskeleton with selected sensors to move and control the upper limbs covering 6 motions: shoulder adduction and abduction, shoulder flexion and extension and elbow flexion and extension. The device is a junction of a hard orthosis with a soft orthosis in order to perform passive physical therapist exercises in clinical practice. The actuation is made by Bowden cables connected in one end to the limb and another to a stepper motor located at a backpack carried by the patient decreasing the apparatus weight substantially. The project also includes a selection of sensors comprising accelerometers, strain gages, thermostats, oximeters, that can provide the necessary information to move the limbs quantifying the muscle activity and physical condition through time. Also, a cooling subsystem based on Peltier thermoelectric modules was implemented to control the muscle temperature in case of an inflammatory reaction. The design was certified by kinematic and structural strength simulation using SolidWorks software.
Lecture Notes in Computer Science, 2018
A military pilot fulfilling his mission can often be caught in precarious situations and put unde... more A military pilot fulfilling his mission can often be caught in precarious situations and put under extreme strain. The aim of this article is to describe the current development of systems and methods for measuring and modelling military pilot’s behavior. The first part of this paper outlines the systems and methods for measuring and evaluation of physical and medical data needed to describe the condition and behavior of military pilots quantitatively. The second part focuses on an expert system approach to modelling military pilot behavior. The authors demonstrate, how the modules of the system were created and how measurements and tests were performed. The research findings outline the new expert system modelling military pilot’s behavior. Moreover, subsystems and sensors applied in the cockpit so that the system as a whole can support the pilot, are described. The complete system is able to determine the pilot’s stress load, along with physical and visual load levels. Based on this knowledge, it is possible to determine whether the pilot needs the support of the automatic flight control system. This system can be also be used in the flight control system and can increase battle effectiveness of the deployed aircrafts.