Wireless Sensor Networks (WSNets), consisting of a lot of Wireless Sensor Nodes (WSNs), play an important role in structural health and machine condition monitoring. But the WSNs provided by the current market cannot meet the diversity of application requirements because they have limited functions, unreliable node performance, high node cost, high system redundancy, and short node lifespan. The aim of the research is to design the architecture of a WSN with low power consumption and node cost, which can be dynamically configured according to application requirements for structural health and machine condition monitoring. This research investigates the improvement of node performance and reliability through the new design methodologies and the extension of node lifespan by interfacing energy harvesters and implementing node power management. The main contributions of the research are presented from the following aspects:1. Model development of node architecture for application diversityThe merits of model include: (1) The proposed node architecture can be dynamically configured in terms of application requirements for reducing system redundancy, power consumption and cost; (2) It supports multichannel signal measurement with the synchronous and asynchronous signal sampling modules and three interface circuits; (3)The model parameters can be calculated; (4) As the model is based on discrete electronic components, it can be implemented by using Components-Off-The-Shelf (COTS).2. A novel pipeline design of the built-in ADC inside a microprocessorThe merit of proposed pipeline solution lies in that the sampling time of the built-in ADCs is reduced to one third of the original value, when the ADC operates in sequence sampling mode based on multichannel signal measurement.3. Self-adjusting measurement of sampled signal amplitude This work provides a novel method to avoid the distortion of sampled signals even though the environmental signal changes randomly and over the sampling range of the node ADC. The proposed method can be implemented with four different solutions.4. Interface design to support energy harvesting The proposed interface will allow to: (1) collect the paroxysmal ambient energy as more as possible; (2) store energy to a distribution super-capacitor array; (3) harvest electrical energy at high voltage using piezoelectric materials without any transformer; (4) support the diversity of energy transducers; and (5) perform with high conversion efficiency.5. A new network task scheduling model for node wireless transceiver The model allows to: (1) calculate node power consumption according to network task scheduling; (2) obtain the optimal policy for scheduling network task.6. A new work-flow model for a WSN The model provides an easy way to (1) calculate node power consumption according to the work flow inside a WSN; (2) take fully advantage of the power modes of node electronic components rather than outside factors; (3) improve effectively node design.

Objectives: The inverse relationship between QT interval variability (QTV) and T wave amplitude potentially confounds QT variability assessment. We quantified the influence of the T wave amplitude on QTV in a comprehensive dataset and devised a correction formula. Methods: Three ECG datasets of healthy subjects were analyzed to model the relationship between T wave amplitude and QTV. To derive a generally valid correction formula, linear regression analysis was used. The proposed correction formula was applied to patients enrolled in the Evaluation of Defibrillator in Non-Ischemic Cardiomyopathy Treatment Evaluation trial (DEFINITE) to assess the prognostic significance of QTV for all-cause mortality in patients with non-ischemic dilated cardiomyopathy. Results: A strong inverse relationship between T wave amplitude and QTV was demonstrated, both in healthy subjects (R2 = 0.68, p < 0.001) and DEFINITE patients (R2 = 0.20, p < 0.001). Applying the T wave amplitude correction to QTV achieved 2.5-times better group discrimination between patients enrolled in the DEFINITE study and healthy subjects. Kaplan-Meier estimator analysis showed that T wave amplitude corrected QTVi is inversely related to survival (p < 0.01) and a significant predictor of all-cause mortality. Conclusion: We have proposed a simple correction formula for improved QTV assessment. Using this correction, predictive value of QTV for all-cause mortality in patients with non-ischemic cardiomyopathy has been demonstrated.

We begin by studying field-theory amplitude relations such as the Kleiss-Kuijf, Bern-Carrasco-Johansson, Kawai-Lewellen-Tye and the double copy construction, which are important ingredients in this thesis. Going beyond the field-theory limit we study how the gauge-sector of the heterotic string relates to type I amplitudes through the single valued projection of multiple zeta values. At low energy and for a U(1) gauge group (a single brane) the type I amplitudes are generated by the Born-Infeld action, whereas the corresponding heterotic amplitudes vanish in this limit. As a simple exercise we study Yang-Mills theory deformed by a $F^4$ operator, which is the first correction induced by the Born-Infeld action. This exercise is then generalized by considering the four- and six-point amplitudes in Tseytlin's proposal for a non-Abelian Born-Infeld action. Comparing these amplitudes with those found in type I and heterotic string theory we attempt to gain more insight about the non-Abelian Born-Infeld action.

INTRODUÇÃO: Estudos com mulheres na faixa dos 50 anos justificam-se porque nesta etapa da vida os declínios fisiológicos são bastante evidentes e relacionados ao climatério e período pós-menopausa. Apesar de viverem mais do que os homens, adoecem mais frequentemente e registram índices mais baixos de saúde percebida do que eles. Melhoras funcionais foram evidenciadas com exercícios na água, todavia são raros os estudos que utilizam a caminhada em imersão como método exclusivo ou principal recurso de intervenção para promoção de saúde. OBJETIVO: Avaliar os efeitos de um programa de 12 meses de caminhada em imersão em mulheres quinquagenárias saudáveis. MÉTODOS: Participaram 59 mulheres em grupos de 10 a 12 participantes que configuraram um único grupo caracterizando-se como um estudo quase-experimental. A intervenção foi realizada 2 vezes por semana em sessões de 30 minutos, por um ano, em piscina aquecida em aproximadamente 310. O programa foi dividido em 4 etapas de 3 meses cada, com evolução crescente na dificuldade dos exercícios. Foram realizadas 5 avaliações: inicial (t0), após 3 meses (t1), 6 meses (t2), 9 meses (t3) e no final do programa - 12 meses (t4). Para a avaliação subjetiva sobre o estado de saúde, mobilidade e humor, foi utilizada uma escala mista de zero a dez. Um breve relato sobre os principais efeitos do programa, com base em questão aberta, também foi analisado. Para a avaliação da força isométrica dos músculos flexores e extensores do quadril e do tornozelo utilizou-se um dinamômetro portátil e para a avaliação da flexibilidade foi utilizado o teste de sentar e alcançar. Para avaliação do equilíbrio foram utilizados os testes de apoio unipodal com olhos abertos (TAU-OA) e fechados (TAU-OF) e o teste \"timed up and go\" (TUG). RESULTADOS: Os resultados observados entre a avaliação inicial e final (t0-t4) do programa mostraram que houve melhora de 16,13% na percepção de saúde (p < 0,001), de 22,15% na mobilidade (p < 0,001) e de 9,69% no humor (p=0,003). Na análise de conteúdo, 49,4% das falas relacionaram-se com a melhora da saúde; 22,9% com a autoestima e satisfação e 19,3% foram relacionadas à capacidade física. A força dos extensores do quadril melhorou 27,67% (p < 0,001), dos flexores do quadril 48,81% (p < 0,001), dos flexores plantares 32,59% (p < 0,001) e dos dorsiflexores 40,75% (p < 0,001). A melhora observada na flexibilidade foi de 54,55% (p < 0,001). O equilíbrio estático avaliado pelo TAU-OA melhorou 35,51% e pelo TAU-OF 261,96% ambos com p < 0,001. Houve melhora de 31,78% no equilíbrio dinâmico (p < 0,001); O equilíbrio, tanto estático como dinâmico e a flexibilidade tiveram melhora em todas as etapas. CONCLUSÃO: O estudo mostrou que esta forma de atividade, realizada em grupos com programa de longa duração, porém de fácil replicação, em 4 etapas progressivas melhorou o estado de saúde, a mobilidade e o estado de humor; a força dos músculos do quadril e do tornozelo, a flexibilidade, bem como o equilíbrio estático e dinâmico das mulheres participantes. Com isto ressaltamos a relevância de políticas públicas que favoreçam e incentivem a prática dos exercícios físicos prazerosos visando um envelhecimento natural e com autonomia funcional / INTRODUCTION: Studies with 50 year-old women are justified because in this stage of life physiological declines are quite evident and related to climacteric and postmenopausal period. Although women live longer than men they fall sick more often and register lower perceived health indices than men do. Functional improvements were observed with immersion exercises, however, studies that use immersion walk as the only method or main intervention resource to promote health are rare. OBJECTIVE: To evaluate the effects of a 12-month immersion walk program in healthy 50 year-old women. METHOD: 59 women participated in groups of 10 to 12 participants which constituted a unique group thus characterized as a quasi-experimental study. The intervention was conducted twice a week, in 30 minute-sessions, for a year, in a pool heated at approximately 31ºC. The program was divided into 4 phases of 3 months each, with increasing evolution in exercise difficulty. 5 evaluations were carried out: initially (t0), after 3 months (t1), 6 months (t2), 9 months (t3) and at the end of the program, 12 months (t4). For the subjective assessment of the health status, mobility and mood, a mixed scale from zero to ten was used. A brief report of the main effects of the program, based on an open question, was also analysed. To evaluate the isometric strength of the flexion and extension muscles of the hip and ankle, a portable dynamometer was used and to evaluate flexibility the sit and reach test was used. To evaluate balance the one-legged stance-open eyes (OLS-OE), the one-legged stance-closed eyes (OLS-CE), and the timed up and go (TUG) tests were used. RESULTS: The results observed between the initial and final evaluation of the program (t0-t4) showed 16.13% improvement in the perception of health (p < 0,001), 22.15% in mobility (p < 0,001) and 9.69% in mood (p= 0,003). In the content analysis, 49.4% of speeches were related to health improvement; 22.9% to self-esteem and satisfaction and 19.3% were related to physical capacity. The strength of hip extensors improved 27.67% (p < 0,001), hip flexors 48.81% (p < 0,001), plantar flexors 32.59% (p < 0,001), and dorsiflexors 40.75% (p < 0,001). Improvement observed in flexibility was 54.55% (p < 0,001). Static balance assessed by OLS-OE improved 35.51% and by OLS-CE 261.96%, both with (p < 0,001). There was a 31.78% improvement in dynamic balance (p < 0,001). Both static and dynamic balance as well as flexibility improved in all phases. CONCLUSION: The study showed that this form of activity, developed in groups with a long-term program, but easily replicated, in 4 progressive stages has improved health status, mobility and mood; hip and ankle muscle strength flexibility, as well as static and dynamic balance of participating women. Thus, we emphasize the relevance of public policies that favour and encourage the practice of pleasurable physical exercises, aiming at a natural aging process with functional autonomy

This diploma thesis deals with the measurement of wind oscillation waves on reservoirs, especially with regard to the determination of wave properties with a focus on the spectral density. The thesis presents the basics of the theory of creation and propagation of wind oscillation waves, the recherche of measuring devices and a description of the pilot measurement with the processing of measured data in the MATLAB environment using the software tool WAFO. Attached to the CD are sample scripts for data processing from the resistance sensor.

The thesis deals with an evaluation of the surface texture of various materials, created by machining technologies (turning, milling and grinding). As for the theoretical part of the thesis, it contains a theoretical analysis of the effect of surface texture on friction, wear, coating and lubricating properties. The main emphasis is put on the analysis of the most frequently evaluated profile and surface parameters as well as their possible influence on the functional areas of machined parts. The experimental part includes evaluated and compared measured data based on the monitored parameters with benefits for machinery industry.

Parametric acoustic arrays are ultrasonic-based loudspeakers that produce highly directive audio. The audio must first be preprocessed and modulated into an ultrasonic carrier before being emitted into the air, where it will self-demodulate in the far field. The resulting audio wave is proportional to the double time-derivative of the square of the modulation envelope. This thesis presents a fully analog processor which encodes the audio into two Pulse Width Modulated (PWM) signals in quadrature phase and sums them together to produce a Single Sideband (SSB) spectrum around the fundamental frequency of the PWM signals. The two signals are modulated between 8% and 24% duty cycle to maintain a quasi-linear relationship between the duty cycle and the output signal level. This also allows the signals to sum without overlapping each other, maintaining a two-level output. The system drives a network of narrowband transducers with a center frequency equal to the PWM fundamental. Because the transducers are voltage driven, they have a bandpass frequency response which behaves as a first-order integrator on the SSB signal, eliminating the need for two integrators in the processor. Results show that the “SSB-PWM” output wave has a consistent 20-30dB difference in magnitude between the upper sideband and lower sideband. In simulation, a single tone test shows higher total harmonic distortion for lower frequencies and higher modulation depth. A two-tone test creates a 2nd order intermodulation term that increases with the frequencies of the input signals.

The purpose of this semestral project is to explain the basic issues of simple digital modulations through the creation of simple digital modulations using direct digital synthesis. It begins with a short review of digital modulation theory and the theory about direct digital synthesis. All the technical documentation is attached, including schematics and boards of functional modulator.

The aim of the master´s thesis is to create a high-frequency amplifier with switching power amplifier classes among classes A, B, C with output power of 10 W. The amplifier operates at frequency from 3.5 MHz to 14 MHz. Master´s thesis includes also theoretical analysis, design of lowpass filter and amplifiers and their simulation, mechanical realization and measured parameters of the amplifier.

Diploma thesis deals with problem of assessment of the second viscosity and acoustic velocity coefficients by the different liquid´s flow in pipe from measured pressure pulstation created by diaphragm pulsator. For the solution is used a transfer matrix model and for the data evaluation a genetic algorithm in „Facharp.exe“ program. Modal analysis in problematic part of the measured stand is realized to find a wave shapes and natural frequency of a pipe. The results are for the reason of clearness processed into „MS Excel“ program and fetched to the charts which shows depedence of a second viscosity and acoustic velocity coefficients on a various flow as the final result.