Contact-less human detection and monitoring using radar technology has been recently applied in many areas including search-and-rescue for earthquake victims, fall detection, gait analysis and detection of other human activities. Radars can also provide important information about a persons state of health by monitoring the level of activities, heart and breathing rate. Also it can be used to generate warnings if some of the monitored parameters are outside of predefined limits. The major application of this work is for monitoring in-mates and their activities. This thesis deals with characterizing the performance of the radar system used for monitoring a single person in a contained environment. This thesis is experimentally based and during the thesis a large number of experiments were performed in order to monitor subjects in realistic conditions. The thesis explores feasibility of using the radar with a single radio-frequency channel input and two algorithms for breathing and heart rate estimation when the subject is at different relative orientation towards the radar as well as in different postures. Algorithm one is using Fast Fourier Transformation (FFT) and algorithm two is using Empirical Mode Decomposition (EMD) with Minkowski distance. We also detect the zones where the subject is when the subject is moving. Since this exploratory analysis provides initial features for classifications and algorithms for breathing and heart beat estimation, it can represent a foundation for future works on designing systems that track subjects and their breathing in real-time.

Předložená práce se zabývá problematikou slepé filtrace obrazů z transmisního elektronového mikroskopu. V úvodu práce je uveden popis transmisního elektronového mikroskopu. Navazující část popisuje mechanismy interakce elektronů se zkoumaným vzorkem a z toho vyplývající zobrazovací techniky elektronové mikroskopie. Poslední kapitola teoretické části práce zahrnuje popis vybraných metod slepé filtrace obrazu zejména s využitím dekompozice obrazu na charakteristické složky. Taktéž je zde uveden výčet metod pro zhodnocení úspěšnosti filtrace. V praktické části jsou popsány aplikované metody slepé filtrace obrazů a výsledky filtrování. Jednotlivé metody jsou mezi sebou porovnány. Získané výsledky a využitelnost aplikovaných metod jsou zhodnoceny v diskuzi.

This work describes basics of electroencephalography, measuring methods of electroen- cephalographic signals, their processing and especially the interpretation of EEG signal in frequency and time-frequency domains for mental fatigue detection purposes. Mental fatigue, its sources, consequences and connection with sensory-cognitive system and link to memory is discussed. The most basic normalized international system for measuring EEG from the scalp as well as some of the experiments that ultimately lead to mental fatigue are described. With this knowledge in mind, an experiment was prepared for inducing such a state. Ten subjects participated in the test which was conducted in la- boratory with EEG machine GES 410MR by EGI. The data were analyzed mainly with S-transform and Hilbert-Huang transform. These two transforms represent two distinct state of the art time-frequency methods of spectral analysis. The result of this work lies in evaluating the relationship between mental fatigue, errors accumulated during the task and with time.

It is important that ambulances are urgently directed to patients who are in need of immediate help and of quick transportation to a hospital. Because resources are limited, emergency medical dispatch centres (EMD) cannot send ambulances with high priority to all callers. The efficiency of the system is therefore dependent on triage. Increased knowledge about the triage in the prehospital care can make it possible to optimize the use of resources. Traditionally nurses have an important role in triage on emergency departments and in telephone advisory. In Sweden there is a trend towards more triage by nurses at EMDs. It is important to survey experiences of nurses’ of prioritization at EMDs. Aim: The overall aim in this thesis was to measure effectivity in prioritisation of ambulance dispatches, and to elucidate experiences from these prioritizations and decisions. Method: In study I sensitivity and specificity in 4086 dispatches was calculated, by comparison of the priority given by the EMD and the assessment performed by the ambulance-nurse according to Medical Emergency Triage and Treatment System. In study II were 15 nurses interviewed about their experiences from prioritizations at an EMD. Result: The result showed that 84,5 % of the dispatches were correct prioritised and that the sensitivity was high (94,5 %) but the specificity was low (15,4 %). Content analysis was performed and two themes emerged: “Having a profession with opportunities and obstacles” and “Meeting serious and difficult situations”. Conclusions are that over- prioritizations are made concerning patients with low or no need of medical care. Also that nurses with experience from emergency care, who are allowed to make their own decisions independent of the medical index, can improve and nuance the prioritization of resources in prehospital care. However, there is an obvious risk that their assessments will tend to be on the safe side. Important for avoiding this is improving internal support systems at the EMDs and also striving for a blame-free culture, where the nurses are not pushed by threats of being reported.

Objective: To examine the influence of a 6-week training program on the electromechanical delay (EMD) and reaction time of the peroneus longus muscle. Design and Setting: The study was guided by a 2 x 2 factorial design with repeated measures on the time factor. The independent variables for this study were group (training and control) and time (pre- and post-training). Dependent variables for this study were muscle reaction time and electromechanical delay of the peroneus longus muscle. Subjects: Thirty-six healthy, physically active, college-age (21.8 ± 2.3 yr) male and female (M = 14, F = 28, height = 173.7 ± 11.2 cm, weight = 69.1 ± 18.4 kg) subjects were recruited for this study. Subjects had experienced no more than one ankle sprain to either ankle in their life, and had not sprained either ankle in the last year. Subjects were not currently experiencing any lower extremity pathology and had no history of serious injury to either lower extremity. Measurements: The EMD of the peroneus longus was determined by the onset of force contribution after a percutaneous electrical stimulation was administered, as measured by EMG and force plate data. Reaction time was measured after a perturbation during walking. Data was analyzed using two 2 X 2 X 2 ANOVAs. Group (treatment and control) and gender were between treatments factors, and time was a within treatments factor. Results: Upon initial examination, there was a trend in the EMD measurements to show an increase in EMD in the treatment group. However, this lacked statistical significance (F = 2.96, p = 0.0983). Reaction time demonstrated a trend towards a decrease in reaction time in the treatment group, but again, this lacked statistical significance (F = 2.88, p = 0.1025). Effect size for this reaction time was 1.2. Conclusions: The 6-week training program used in this study did not have a significant effect on the reaction time and electromechanical delay of the peroneus longus muscle.

This thesis is focused on EEG processing and emotion classification within two-dimensional emotion space. First part consists of theoretical research about emotional responses of human subjects on sound, image and video stimuli. Emotions are examined from aspect of physiology and psychology. Furthermore technical overview of measurement, analysis and emotion classification within two-dimensional emotional space is discussed. Based on gathered knowledge measurement setup with audiovisual stimuli was designed and measured with two independent instruments – EGI GES400MR in laboratory conditions and Emotiv EPOC device in non-laboratory conditions. Signals were processed and emotions were classified based on chosen features. Performance of classifiers in multiple feature selection setups was evaluated.

The aim of this thesis is to introduce with principle of Empirical Mode Decomposition method and possibility use for correction of baseline wander in ECG signals. The thesis describes the main components of the ECG signal, a selection of possible types of signal noise, its property and principles of chosen methods for filtration of ECG signals. In conclusion the evaluation of the effectiveness of the EMD method for filtering a baseline wander and it comparing with effectiveness of the linear filtration. Functionality of used algorithms has been tested on signals of CSE standard library.

This dissertation explores the potential of EMD as analyzing tool for audio and speech processing. This signal expansion into IMFs is adaptive and without any prior assumptions (stationarity and linearity) on the signal to be analyzed. Salient properties of EMD such as dyadic filter bank structure, quasi-symmetry of IMF and fully description of IMF by its extrema, are exploited for denoising, coding and watermarking purposes. In speech signals denoising, we initially proposed a technique based on IMFs thresholding. A comparative analysis of performance of this technique compared to the denoising technique based on the wavelet. Then, to remedy the problem of the MMSE filters which requires an estimation of the spectral properties of noise, we introduced the ACWA filter in the denoising procedure. The proposed approach is consisted to filter all IMFs of the noisy signal by ACWA filter. This filtering approach is implemented in the time domain, and also applicable in the context of colored noise. Finally, to handle the case of hybrid speech frames, that is composed of voiced and unvoiced speech, we introduced a stationarity index in the denoising approach to detect the transition between the mixture of voiced and unvoiced sounds. In audio signals coding, we proposed four compression approaches. The first two approaches are based on the EMD, and the other two approaches exploit the EMD in association with Hilbert transform. In particular, we proposed to use a predictive coding of the instantaneous amplitude and frequency of the IMFs Finally, we studied the problem of audio signals watermarking in context of copyright protection. The number of IMFs can be variable depending on the attack type. The proposed approach involves inserting the mark in the extrema of last IMFs. In addition, we introduced a synchronization code in the procedure in order to facility the extraction of the mark. These contributions are illustrated on synthetic and real data and results compared to well established methods such as MMSE filter, wavelets approach, MP3 and AAC coders showing the good performances of EMD based signal processes. These findings demonstrate the real potential of EMD as analyzing tool (in adaptive way) in speech and audio processing.

Submitted by Juliana Crespo (juliana.crespo4@gmail.com) on 2018-09-11T13:45:16Z No. of bitstreams: 1 Disserta__o_Mestrado-merged.pdf: 4063780 bytes, checksum: f6ae8f648e0fa9a35cae1d80aacf9d16 (MD5) / Approved for entry into archive by Janete de Oliveira Feitosa (janete.feitosa@fgv.br) on 2018-09-18T13:45:25Z (GMT) No. of bitstreams: 1 Disserta__o_Mestrado-merged.pdf: 4063780 bytes, checksum: f6ae8f648e0fa9a35cae1d80aacf9d16 (MD5) / Made available in DSpace on 2018-09-27T12:22:57Z (GMT). No. of bitstreams: 1 Disserta__o_Mestrado-merged.pdf: 4063780 bytes, checksum: f6ae8f648e0fa9a35cae1d80aacf9d16 (MD5) / A transformada de Hilbert-Huang é um método relativamente recente para ana- lisar séries temporais. Incentivados por seus resultados positivos em séries temporais de diversas naturezas, decidimos implementar o mesmo em duas bases de dados de mobilidade urbana do Rio de Janeiro, sendo uma de GPS de ônibus e a outra de telefonia celular, para encontrar possíveis ciclos, sazonalidades e tendências, ao longo dos anos, devido a mudanças significativas nas vias exploradas.

Conventional rotating machine vibration monitoring techniques are based on the assumption that changes in the measured structural response are caused by deterioration in the condition of the rotating machine. However, due to variations of the rotational speed, the measured signal may be non-stationary and difficult to interpret. For this reason, the order tracking technique is introduced. One of main advantages of order tracking over traditional vibration monitoring lies in its ability to clearly identify non-stationary vibration data and to a large extent exclude the influences of varying rotational speed. In recent years, different order tracking techniques have been developed. Each of these has their own pros and cons in analyzing rotating machinery vibration signals. In this research, three existing order tracking techniques are extensively investigated and combined to further explore their abilities in the context of condition monitoring. Firstly, computed order tracking is examined. This allows non-stationary effects due to the variation of rotational speed to be largely excluded. However, this technique was developed to deal with the entire raw signal and therefore looses the ability to focus on each individual order of interest. Secondly, Vold-Kalman filter order tracking is considered. It is widely reported that this technique overcomes many of the limitations of other order tracking methods and extracts order signals into the time domain. However because of the adaptive nature of the Vold-Kalman filter, the non-stationary effects due to the rotational speed will remain in the extracted order waveform, which is not ideal for conventional signal processing methods such as Fourier analysis. Yet, the strict mathematical filter (the Vold-Kalman filter is based upon two rigorous mathematical equations, namely the data equation and the structural equation, to realize the filter) gives this technique an excellent ability to focus on the orders of interest. Thirdly, the empirical mode decomposition method is studied. In the literature, this technique is claimed to be an effective diagnostic tool for various kinds of applications including diagnosis of rotating machinery faults. Its unique empirical way of extracting non-stationary and non-linear signals allows it to capture machine fault information which is intractable by other order tracking methods. But since there is no precise mathematical definition for an intrinsic mode function in empirical mode decomposition and – as far as could be ascertained – no published assessment of the relationship between an order and an intrinsic mode function, this technique has not been properly considered by analysts in terms of order tracking. As a result, its abilities have not really been explored in the context of order related vibrations in rotating machinery. In this research, the relationship between an order and an intrinsic mode function is discussed and it is treated as a special kind of order tracking method. In stead of focusing individually on each order tracking technique, the current work synthesizes different order tracking techniques. Through combination, exchange and reconciliation of ideas between these order tracking techniques, three improved order tracking techniques are developed for the purpose of enhancing order tracking analysis in condition monitoring. The techniques are Vold-Kalman filter and computed order tracking (VKC-OT), intrinsic mode function and Vold-Kalman filter order tracking (IVK-OT) and intrinsic cycle re-sampling (ICR). Indeed, these improved approaches contribute to current order tracking practice, by providing new order tracking methods with new capabilities for condition monitoring of systems which are intractable by traditional order tracking methods, or which enhances results obtained by these traditional methods. The work commences with a discussion of the inter-relationship between the order tracking methods which are considered in the thesis, and exposition of the scope of the work and an explanation of the way these independent order tracking techniques are integrated in the thesis. To demonstrate the abilities of the improved order tracking techniques, two simulation models are established. One is a simple single-degree-of-freedom (SDOF) rotor model with which VKC-OT and IVK-OT techniques are demonstrated. The other is a simplified gear mesh model through which the effectiveness of the ICR technique is proved. Finally two experimental set-ups in the Sasol Laboratory for Structural Mechanics at the University of Pretoria are used for demonstrating the improved approaches for real rotating machine signals. One test rig was established to monitor an automotive alternator driven by a variable speed motor. A stator winding inter-turn short was artificially introduced. Advantages of the VKC-OT technique are presented and features clear and clean order components under non-stationary conditions. The diagnostic ability of the IVK-OT technique of further decomposing an intrinsic mode function is also demonstrated via signals from this test rig, so that order signals and vibrations that modulate orders in IMFs can be separated and used for condition monitoring purposes. The second experimental test rig is a transmission gearbox. Artificially damaged gear teeth were introduced. The ICR technique provides a practical alternative tool for fault diagnosis. It proves to be effective in diagnosing damaged gear teeth. / Thesis (PhD)--University of Pretoria, 2011. / Mechanical and Aeronautical Engineering / unrestricted