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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
241

Efeito do método Pilates nos parâmetros de desempenho neuromuscular em idosos com dor lombar /

Tozim, Beatriz Mendes. January 2018 (has links)
Orientador: Marcelo Tavella Navega / Banca: Ana Elisa Zuliani Stroppa Marques / Banca: Paulo Roberto Rocha Junior / Banca: Cristiane Rodrigues Pedroni / Banca: Marcos Renato de Assis / Resumo: A dor lombar (DL) crônica no idoso ocasiona diminuição da resistência e força dos músculos extensores de tronco, flexibilidade, modificações neuromusculares. O exercício terapêutico tem o intuito de manter e ou melhorar as condições físicas ocasionadas pela dor lombar, entre as terapêuticas existe a Protocolo cinesioterapêutico (CIN), que usa exercícios combinados e o método Pilates (MP). OBJETIVO:Analisar o MP e FC na dor, resistência muscular, flexibilidade, força, recrutamento e co-contração dos músculos do tronco de idosas com DL, e comparar com um grupo de ações educativas. MÉTODOS:Participaram do estudo 41 idosas, com DL crônica, divididas em: Grupo Pilates (GP, n=14; 66,71±3,56anos), Grupo CIN (GCIN, n=13; 68,46±4,89anos) e Grupo ações educativas (GAE, n=14; 68,00±4,66anos). A avaliação foi composta pelos testes para: dor (Escala visual analógica), resistência muscular (Teste Biering-Sorensen-TBS), flexibilidade (Sentar e Alcançar, Ângulo Poplíteo), força muscular (FM) e eletromiografia dos músculos tronco (Iliocostal-IL, Multífido- MU, Oblíquo interno- OI). Ao fim da avaliação GP e GCIN realizaram 16 sessões em 8 semanas, e GAE quatro palestras em 8 semanas. A análise estatística usou os testes Shapiro-Wilk, Análise multivariada, analise de Variância Mista e correlação de Pearson (p≤0,05). RESULTADOS: No GP diminuiu a dor (p=0,003), maior resistência muscular (p<0,001) e FM(p=0,003), redução do recrutamento de IL direito durante TBS (p=0,05), co-contração de OI/MU esq... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Chronic low back pain (LBP) in the length of the endurance and the strength of the extensor muscles of the trunk, flexibility, neuromuscular modifications. Therapeutic exercise is intended to maintain and improve as the possibilities are caused by LBP, among which there is a kinesiotherapeutic exercise (KT), which uses combined exercise, and Pilates Method (PM). OBJECTIVE: To analyze PM and KT in pain, muscular endurance, flexibility, strength, recruitment and co-contraction of the trunk muscles of elderly women with LBP, and compare with a group educational actions. METHODS:41 elderly women with chronic LBP were divided into: Pilates Group (PG, n = 14, 66.71 ± 3.56 years), KT Group (KTG, n = 13, 68.46 ± 4.89 years) and Group educational actions (EAG, n = 14; 68,00 ± 4,66 years). The tests was evaluated for: pain (Visual Scale Analogy), muscle endurance (Biering-Sorensen test-BST), flexibility (sitting and reaching, popliteal angle), muscle strength (MS) and electromyography of the trunk muscles ( Iliocostal-IL,Multifido- MU, Internal Oblique - OI). The PG and KTG evaluation were performed 8 weeks with16 session, and EAG 8 weeks with 4 lesion. A statistical analysis used the Shapiro-Wilk tests, Multivariate Analysis, Analysis of Variance and Pearson's Key (p≤0.05). RESULTS:PG decreased pain (p = 0.003), higher muscle endurance (p <0.001) and MS (p = 0.003), reduction of right IL recruitment during BST (p = 0.05), IO/MU co-contraction (p = 0.004), increased recruitment of IL F... (Complete abstract click electronic access below) / Doutor
242

Advanced Signal Processing for Pulse-Amplitude Modulation Optical Transmission Systems

Prodaniuc, Cristian 25 February 2019 (has links)
[ES] Los sistemas de transmisión óptica no-coherente se emplean actualmente en las redes ópticas de corto alcance (< 80 km), como son las redes de ámbito metropolitano. La implementación más común en el estado del arte se basa en sistemas que emplean multiplexación por división en longitud de onda (WDM, wavelength division multiplexing) de cuatro longitudes de onda (¿) proporcionando un régimen binario de 100 Gbps (4¿×25 Gbps). En los últimos años, los sistemas de transmisión ópticos no-coherentes están evolucionando desde 100 Gbps a 400 Gbps (4¿×100 Gbps). Dado que este mercado comprende un gran número de sistemas, el coste es un parámetro importante que debe ser lo más bajo posible. El objetivo de esta tesis es investigar distintos aspectos del procesado de señal en general y, específicamente, investigar nuevas técnicas de procesado digital de señal (DSP, digital signal processing) que puedan ser utilizadas en sistemas de transmisión óptica no-coherentes empleando la modulación por amplitud de pulsos (PAM, pulse-amplitude modulation). Para que una técnica DSP sea interesante en el contexto de una red óptica WDM no-coherente, esta debe mitigar de manera efectiva al menos una de las tres limitaciones principales que afectan a estos sistemas: limitaciones de ancho de banda, limitaciones por dispersión cromática (CD), y el ruido. En esta tesis se proponen y examinan una serie de algoritmos cuyo su rendimiento es analizado mediante simulación y experimentalmente en laboratorio: - Feed-forward equalizer (FFE): este es el esquema de ecualización más común que se emplea principalmente en las transmisiones ópticas no-coherentes de alto régimen binario. Puede compensar grandes limitaciones en el ancho de banda. - Estimación de la secuencia de máxima verosimilitud (MLSE): el MLSE es un detector óptimo y, por lo tanto, proporciona las mejores prestaciones en detección cuando se abordan las limitaciones por CD y de ancho de banda. - Conformación geométrica de la constelación: en los esquemas de modulación de intensidad óptica multinivel, la distancia entre los niveles de amplitud puede ajustarse adecuadamente (de manera que no son equidistantes) a fin de aumentar la tolerancia de la señal frente al ruido. - Conformación probabilística: técnica diseñada específicamente para esquemas de modulación multinivel. Esta técnica ajusta la probabilidad de cada nivel de amplitud de modo que se incrementa la tolerancia al ruido óptico. - Señalización de respuesta parcial (PRS, partial signaling response): este es un enfoque basado en DSP donde una interferencia entre símbolos (ISI, inter-symbol interference) controlada es introducida intencionalmente de tal manera que la señal resultante requiere menos ancho de banda. La técnica PRS puede adaptarse para combatir también el efecto de CD. - Pre-énfasis digital (DPE, digital pre-emphasis): esta técnica consiste en aplicar el inverso de la función de transferencia del sistema a la señal en el transmisor, lo que reduce el impacto de las limitaciones de ancho de banda en el receptor. - Modulación con codificación Trellis (TCM, Trellis-coded modulation): esquema de modulación que combina elementos de corrección de errores (FEC, forward error correction) con técnicas de partición en conjuntos y modulación multidimensional para generar una señal más resistente al ruido. - Modulación multidimensional por partición en conjuntos: muy similar a TCM, pero sin ningún elemento FEC. Tiene menos ganancias que TCM en términos de tolerancia al ruido, pero no es tan sensible al ISI. Utilizando estas técnicas, esta tesis demuestra que es posible lograr una transmisión óptica con régimen binario de 100 Gbps/¿ empleando componentes de bajo coste. En esta tesis también demuestra regímenes binarios de más de 200 Gbps, lo que indica que la transmisión óptica no-coherente con modulación PAM puede ser una solución viable y eficiente en coste / [CAT] Actualment, s'utilitzen sistemes òptics no coherents en xarxes òptiques de curt abast ( < 80 km), com són les xarxes d'àmbit metropolità. La implementació més comuna que podem trobar en l'estat de l'art es correspon amb sistemes emplenant multiplexació per divisió en longitud d'ona (WDM, wavelength division multiplexing) de quatre longituds d'ona (¿) proporcionant un règim binari de 100 Gbps (4¿×25 Gbps). En els últims anys, els sistemes de transmissió òptica no-coherents han evolucionat des de 100 Gbps cap a 400 Gbps (100 Gbps/¿). Atès que el mercat de sistemes de curt abast compren un gran volum de dispositius òptics instal·lats, el cost unitari és molt important i ha de ser el més baix possible. L'objectiu d'aquesta tesi és analitzar aspectes del processament de senyal en general i, específicament, investigar noves tècniques de processament digital de senyal (DSP, digital signal processing) que puguen ser utilitzades en sistemes de transmissió òptica no-coherent que utilitzen la modulació per amplitud d'impulsos (PAM, pulse-amplitude modulation). Per tal que una tècnica DSP es considere interessant per a una xarxa òptica WDM no-coherent, aquesta ha de mitigar efectivament almenys una de les tres principals limitacions que afecten aquests sistemes: limitacions d'ample de banda, limitacions per dispersió cromàtica (CD), i el soroll. En aquesta tesi s'examinen una sèrie d'algoritmes, el seu rendiment s'analitza per simulació i experimentalment en laboratori: - Feed-forward equalizer (FFE): aquest és l'esquema d'equalització més comú i s'utilitza bàsicament en les transmissions òptiques no coherents d'alt règim binari. Pot compensar grans quantitats de limitacions d'ample de banda. - Estimació de la seqüència de probabilitat màxima (MLSE): el MLSE és un detector òptim i, per tant, proporciona el millor rendiment quan es tracta de limitacions d'ample de banda i de CD. - Conformació geomètrica de la constel·lació: en esquemes de modulació òptica d'intensitat multinivell es pot ajustar la distància entre els nivells d'amplitud (de manera que ja no són equidistants) per augmentar la tolerància del senyal al soroll. - Conformació probabilística: una tècnica dissenyada específicament per als esquemes de modulació multinivell; ajusta la probabilitat de cada nivell d'amplitud de manera que augmenta la tolerància al soroll òptic. - Senyalització de resposta parcial (PRS, partial signaling response): és un enfocament basat en DSP on la interferència entre símbols (ISI, inter-symbol interference) controlada s'introdueix intencionalment de manera que el senyal resultant requereix menys ample de banda. La tècnica PRS es pot adaptar per combatre els efectes del CD. - Pre-èmfasi digital (DPE, digital pre-emphasis): aquesta tècnica consisteix a aplicar la inversió de la funció de transferència del sistema a la senyal en el transmissor de manera que es redueix l'impacte de les limitacions d'ample de banda en la senyal en el receptor. - Modulació amb codificació Trellis (TCM, Trellis-coded modulation): esquema de modulació que combina els elements de correcció d'errors avançats (FEC, forward error correction) amb tècniques de partionament de conjunts i modulació multidimensional per generar un senyal més resistent al soroll. - Modulació multidimensional per partició en conjuntes: molt similar a TCM però sense elements FEC. Té guanys menors que TCM en termes de tolerància al soroll, però no és tan sensible a l'ISI. Mitjançant l'ús d'aquestes tècniques, aquesta tesi demostra que és possible aconseguir una transmissió òptica amb un règim binari de 100 Gbps/¿ utilitzant components de baix cost. Esta tesi també demostra règims binaris de més de 200 Gbps, el que indica que la tecnologia no-coherent amb modulació PAM és una solució viable i eficient en cost per a una nova generació de sistemes transceptors òptics WDM funcionant a 800 Gbps (4¿×200 G / [EN] Non-coherent optical transmission systems are currently employed in short-reach optical networks (reach shorter than 80 km), like metro networks. The most common implementation in the state-of-the-art is the four wavelength (¿) 100 Gbps (4¿×25 Gbps) wavelength division multiplexing (WDM) transceiver. In recent years non-coherent optical transmissions are evolving from 100 Gbps to 400 Gbps (4¿×100 Gbps). Since in the short-reach market the volume of optical devices being deployed is very large, the cost-per-unit of the devices is very important, and it should be as low as possible. The goal of this thesis is to investigate some general signal processing aspects and, specifically, digital signal processing (DSP) techniques required in non-coherent pulse-amplitude modulation (PAM) optical transmission, and also to investigate novel algorithms which could be applied to this application scenario. In order for a DSP technique to be considered an interesting solution for non-coherent WDM optical networks it has to effectively mitigate at least one of the three main impairments affecting such systems: bandwidth limitations, chromatic dispersion (CD) and noise (in optical or electrical domain). A series of algorithms are proposed and examined in this thesis, and their performance is analyzed by simulation and also experimentally in the laboratory: - Feed-forward equalization (FFE): this is the most common equalizer and it is basically employed in every high-speed non-coherent optical transmission. It can compensate high bandwidth limitations. - Maximum likelihood sequence estimation (MLSE): the MLSE is the optimum detector and thus provides the best performance when it comes to dealing with CD and bandwidth limitations. - Geometrical constellation shaping: in multilevel optical intensity modulation schemes the distance between amplitude levels can be adjusted (such that they are no longer equidistant) in order to increase the signal's tolerance to noise. - Probabilistic shaping: another technique designed specifically for multilevel modulation schemes; it adjusts the probability of each amplitude level such that the tolerance to optical noise is increased. - Partial response signaling (PRS): this is a DSP-based approach where a controlled inter-symbol interference (ISI) is intentionally introduced in such a way that the resulting signal requires less bandwidth. PRS can be customized to also mitigate CD impairment, effectively increasing transmission distances up to three times. - Digital pre-emphasis (DPE): this technique consists in applying the inverse of the transfer function of the system to the signal at the transmitter side which reduces the impact of bandwidth limitations on the signal at the receiver side. - Trellis-coded modulation (TCM): a modulation scheme that combines forward error correction (FEC) elements with set-partitioning techniques and multidimensional modulation to generate a signal that is more resistant to noise. - Multidimensional set-partitioned modulation: very similar with TCM but without any FEC elements. It has lower gains than TCM in terms of noise tolerance but is not so sensitive to ISI. By using the techniques enumerated above, this thesis demonstrates that is possible to achieve 100 Gbps/¿ optical transmission bitrate employing cost-effective components. Even more, bitrates higher than 200 Gbps are also demonstrated, indicating that non-coherent PAM is a viable cost-effective solution for next-generation 800 Gbps (4¿×200 Gbps) WDM transceivers. / Prodaniuc, C. (2019). Advanced Signal Processing for Pulse-Amplitude Modulation Optical Transmission Systems [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/117315 / TESIS
243

Full-waveform inversion for large 3-D salt bodies

Kalita, Mahesh 05 May 2019 (has links)
The ever-expanding need for energy, including those related to fossil fuels, is behind the drive to explore more complicated regions, such as salt and subsalt provinces. This exploration quest relies heavily on recorded surface seismic data to provide precise and detailed subsurface properties. However, conventional seismic processing algorithms including the state-of-the-art full-waveform inversion (FWI) fail to recover those features in many areas of salt provinces. Even the industrial solution with substantial involvement of manual human-interpretation has faced challenges in many regions. In this thesis, I attempt to replace those manual, and somewhat erroneous, steps to the velocity building in salt provinces with a mathematically robust algorithm under the FWI machinery. I, specifically, regularize FWI by penalizing the velocity drops with depth with a new more flexible function. Although promising, FWI is computationally very expensive, especially for large 3D seismic data. It updates an initial guess of the model iteratively using the gradient of the misfit function, which requires lengthy computations and large memory space/disc storage. Based on the adjoint state method, gradient computation usually requires us to store the source wavefield, or include an additional extrapolation step to propagate the source wavefield from its temporary storage at the boundary. To mitigate this computational overburden, I propose an amplitude excitation gradient calculation based on representing the source wavefield history by a single, specifically the most energetic arrival. In this thesis, I also propose a novel-multiscale scheme based on ux-corrected transport (FCT) to reduce artifacts in the gradient direction due to the noise present in seismic data. FCT comprises of two finite difference schemes: a transport and a diffusion to compute the flux at a grid point. I observe a couple of benefits in FCT-based FWI. First, it yields a smooth gradient at the earlier iterations of FWI by promoting the lower frequency content of the seismic data. Second, it is easily compatible with the existing FWI code, and with any objective function. The multiscale strategy starts with a large smoothing parameter and relaxes it progressively to zero to achieve the final inverted model from traditional FWI.
244

Comparison of phase synchronization measures for identifying stimulus- induced functional connectivity in human magnetoencephalographic and simulated data / 位相同期解析に基づく機能的結合指標の検出能比較-脳磁図データおよびシミュレーションデータを用いた検討

Yoshinaga, Kenji 24 November 2020 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第22828号 / 医博第4667号 / 新制||医||1047(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 村井 俊哉, 教授 古川 壽亮, 教授 高橋 淳 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM
245

Analýza vlivu tlumení na velikost odezvy při dynamickém buzení světlometu / Analysis of the effect of damping on the magnitude of the response during dynamic headlamp excitation

Lukáš, Jan January 2020 (has links)
The aim of the submitted diploma thesis is the magnitude determination of the headlamp response to the dynamic excitation. Currently it is necessary to measure this response, because it is one of the assessed criteria of quality of the headlamp. When comparing results of the experimental measurement and the computational modelling, a good consensus of resonant frequencies is observed, but there are significant differences in acceleration amplitudes. The cause of this is the variable damping value. The theoretical part of the thesis deals with polymeric materials, basics of oscillation and damping. It serves to understand the mechanisms, which influence the results of the experimental measurement. The practical part is dedicated to the procedure of the computational modelling and the experimental measurement implementation. The analysis of the experimental measurement results leads to an ascertainment of nonlinearities, which influence the headlamp behaviour. The results of a sensitivity analysis of the computational modelling are used to create curves, on the basis of which the damping is estimated. The inclusion of the estimated damping into computational modelling leads to reduction of the compared differences of the acceleration amplitudes. The conclusion of the thesis contains the recommendation for the damping determination during the computational modelling of the headlamp.
246

Myoelectrical activity in elite and recreational fly casters in trout distance and trout accuracy

Ingemansson, Jimmy January 2021 (has links)
No description available.
247

Optimalizace telekomunikačního výukového prostředí / Optimization of telecommunication education environment

Jeřábek, Josef January 2008 (has links)
The intended goal within the scope of this master´s thesis is to get acquainted with the product of EMONA INSTRUMENTS Company. There are two main concepts: the software version TutorTIMS – Advanced and the hardware version TIMS-301. Both concepts were bought into the laboratory, where the following subjects are being lectured: “Access and transport networks” and “Telecommunication network services”. Three laboratory exercises were prepared for both software version and hardware version. Both versions are modular and all designed exercises support independent and creative approach of students. All exercises also consist of standard parts, which are the description of the exercise and exemplary protocol solution. The first exercise is called “amplitude modulation” and is designed as an introductory exercise. Next are a couple of exercises which are designed to be performed on one workplace at the same time. The first of them is focused on practical verification of facts from amplitude shift keying, the second one focuses on link codes. This couple of exercises is the best choice, considering the hardware version of TIMS-301 and at the present time available modules in the lab. Software version is not limited in such way, but it was required to allow performing all of prepared exercises on both versions. Lastly there is a comparison between the software and hardware version and several options for hardware TIMS optimization.
248

Výkonový zesilovač pro pásmo krátkých vln / Shortwave power amplifier

Fiala, Roman January 2016 (has links)
This master’s thesis describes RF power amplifier design. The designed amplifier has been built. The first three chapters outline basics about radio frequency amplifiers. The basic theory needed for amplifier implementation is also described there. In the fourth chapter the power amplifier is designed. The design is based on the theoretical knowledge. Complete amplifier contains RF preamplifier, power amplifier and filters. The OrCAD PSpice, Ansoft Designer SV and EAGLE programs have been used for the design and verification of some sections of circuits. Measurement results of the built amplifier are in the fifth chapter. This thesis contains also the draft for laboratory exercise.
249

Chi-Squared Analysis of Measurements of Two Cosmological Parameters Over Time

Faerber, Timothy January 2019 (has links)
For this project, a historical statistical analysis of the Amplitude of Mass Fluctuations ($\sigma_8$) and Hubble's Constant ($H_0$) parameters in the Standard Cosmological Model was carried out to determine whether or not the given error bars truly represent the dispersion of values. It was found through analysis of the Chi-Squared ($\chi^2$) values of the data that for $\sigma_8$ (60 data points and $\chi^2$ between 183.167 and 189.037) that the associated probability Q is extremely low, with $Q = 1.5597*10^{-15}$ for the weighted average and $Q = 1.2107*10^{-14}$ for the best fit of the data. This was also the case for the $\chi^2$ values (163 data points and $\chi^2$ between 484.3977 and 575.655) of $H_0$, where $Q = 4.2176*10^{-34}$ for the linear fit of the data and $Q = 1.0342*10^{-47}$ for the weighted average of the data. Through further analysis, it is shown in question, a linear fit is a better estimate of the data than the weighted average. The general conclusion is that the statistical error bars have been underestimated (in around 20\% of the measurements), or the systematic errors were not properly taken into account.
250

Hypersonic Stationary Crossflow Waves: Receptivity to Roughness

Varun Viswanathan (8032571) 04 December 2019 (has links)
<div>Experiments were performed on a sharp-nosed 7° half-angle cone at a 6° angle of attack in the Boeing/AFOSR Mach-6 Quiet Tunnel (BAM6QT) to study the stationary crossflow instability and its receptivity to small surface roughness. Heat transfer measurements were obtained using temperature sensitive paint (TSP) and Schmidt Boelter (SB) heat transfer gauges. Great care was taken to obtain repeatable, quantitative measurements from TSP.</div><div></div><div>Consecutive runs were performed at a 0° angle of attack, and the heat transfer measured by the SB was found to drop as the initial model temperature increased, while other initial conditions such as stagnation pressure were held constant. This agreed with calculations done using a similarity solution. It was found that repeatable measurements at a 6° angle of attack could be made if the initial model temperature was controlled and the patch location that was used to calibrate the TSP was picked in a reasonable and consistent manner.</div><div></div><div>The Rod Insertion Method (RIM) roughness, which was used to excite the stationary crossflow instability, was found to be responsible for the appearance of the streaks that were analyzed. The signal-to-noise ratio in the TSP was too low to properly measure the streaks directly downstream of the roughness insert. The heat transfer along the streak experienced linear growth, peaked, and then slightly decayed. It is possible this peak was saturation. The general trend was that the growth of the streaks moved farther upstream as the roughness element height increased, which agreed with past computations and low speed experiments. The growth of the streak also moved farther upstream as the freestream Reynolds number increased. The amplitude of the streaks was calculated by non-dimensionalizing the heat transfer using the laminar theoretical mean-flow solution for a 7° half-angle cone at a 6° angle of attack. The relationship between the amplitude and the non-dimensional roughness height was approximately linear in the growth region of the streaks.</div>

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