La métrologie de haute précision est une application des peignes de fréquences optiques. Typiquement, la sensibilité de mesure est limitée par le bruit classique des propriétés des peignes. Leur bruit d'amplitude et de phase a été largement étudié et jusqu'à présent. Pourtant, uniquement des bandes latérales de bruit proche de la porteuse ont été caractérisées pour des fréquences individuelles et le champs moyen.Cette thèse développe des méthodes de caractérisation de bruit d'amplitude et phase à la limite quantique. A cette fin, une cavité passive et large bande est développée. Elle filtre et inter-convertit les bruits d'amplitude et phase. L'analyse de son signal à l'aide d'une détection homodyne permet la mesure du bruit de phase avec une sensibilité à la limite quantique. L'application d'un façonnage des impulsions ultra brèves rend possible la mesure des corrélations spectrales du bruit. Tout en étant représentés par des matrices de covariance, l'ensemble des corrélations du bruit sur le spectre optique d'un oscillateur Ti:Sapph est caractérisé.Les corrélations mesurées montrent des structures spectrales, dites " modes ", qui sont en accord avec la prédiction théorique. Ce concept apparait comme analogue au formalisme décrivant des systèmes multi-partites en optique quantique. Il est par conséquent aussi un moyen de description de bruit classique. La connaissance des modes intrinsèques du bruit est susceptible de mener à une amélioration de la précision de mesures avec des peignes de fréquences optiques. / Precision metrology is one application of optical frequency combs. Classical noise in their properties typically limits achievable measurement sensitivity. Amplitude and phase noise in optical frequency combs have already been studied extensively. So far, noise sidebands close to the carrier of either individual optical frequencies or of the mean field were considered. This thesis develops methods to precisely characterize amplitude and phase noise down to the quantum limit. To this aim a transmissive, broadband passive cavity is developed. It filters and inter-converts amplitude and phase noise. The analysis of its signal by the use of homodyne detection provides a quantum limited measurement of phase noise. The application of ultrafast pulse shaping enables the measurement of the spectral correlations of amplitude and phase noise. Being represented by the use of covariance matrices, the entire noise correlations over the optical spectrum are characterized on the example of a Ti:Sapph oscillator. The measured noise correlations exhibit spectral structures, so-called “modes”. Their shape matches with the theoretical prediction. This concept known from multi-partite optical quantum systems is consequently applicable to classical noise in frequency combs. The knowledge of the intrinsic noise modes is likely provide an improvement of precision metrology experiments with combs.

Orientador: Vera Aparecida Madruga / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Educação Física / Made available in DSpace on 2018-08-18T10:46:08Z (GMT). No. of bitstreams: 1 Conceicao_MiguelSoares_M.pdf: 1532956 bytes, checksum: 8b4cb337b2669a48e0b8c68602a72f25 (MD5) Previous issue date: 2011 / Resumo: O presente estudo analisou as alterações nos marcadores indiretos de dano muscular após uma sessão de ações excêntricas de flexores do cotovelo com diferentes velocidades de movimento, em mulheres jovens e na pós-menopausa. Participaram da pesquisa 37 mulheres, voluntárias, com idade compreendida entre 18 a 65 anos. Essas voluntárias foram divididas em quatro grupos. Grupo de mulheres jovens que executou ações excêntricas com velocidade rápida (n=10) e grupo de jovens que executou ações excêntricas com velocidade lenta (n=9). Grupo de mulheres na pós-menopausa que realizou as ações excêntricas com velocidade rápida (n=10) e grupo de mulheres na pós-menopausa que realizou as ações excêntricas com velocidade lenta (n=8). As ações excêntricas foram realizadas no braço não dominante, utilizando-se um dinamômetro isocinético, e consistiram em 30 ações excêntricas máximas divididas em cinco séries de seis repetições. Para analisar a magnitude do dano muscular foram utilizados marcadores indiretos como a contração isométrica voluntária máxima (CIVM), amplitude de movimento (AM), circunferência de braço, dor muscular, creatina quinase (CK), interleucina-6 (IL-6), fator de necrose tumoral (TNF-?) e prostaglandina (PGE2). A CIVM, AM, dor muscular e circunferência de braço foram avaliadas pré, imediatamente após, 24, 48 e 72h após a execução de ações excêntricas. Para a atividade plasmática da CK, IL-6, TNF-? e PGE2, as coletas aconteceram pré, 24, 48 e 72h após as ações excêntricas. Como resultado desta dissertação é apresentado um artigo original. O objetivo do estudo original apresentado foi comparar as alterações dos marcadores de dano muscular e inflamação entre mulheres jovens e na pós-menopausa após ações excêntricas. Diferenças significantes entre grupos foram encontradas para torque excêntrico e TNF-? na qual, mulheres na pós-menopausa apresentaram maiores valores (p<0,05). Uma correlação positiva significante (p<0,05) se estabeleceu entre idade x dor e idade x PGE2. Concluindo, esses resultados não suportam a hipótese que mulheres na pós-menopausa são mais susceptíveis ao dano muscular induzido por ações excêntricas comparado a mulheres jovens / Abstract: The present study have analyzed the changes in muscle damage and inflammatory markers after an acute bout of elbow flexors eccentric exercise at difference velocities, in young and post menopausal women. 37 women aged between 18 and 65 participated of the study. They were divided into four groups, (1) fast velocity, young women (n = 10); (2) slow velocity, young women (n = 9); (3) fast velocity, postmenopausal women (n = 10) and (4) slow velocity, postmenopausal women (n = 8). Eccentric exercise consisted of five sets of six maximal elbow flexors eccentric repetitions performed with the nondominant arm in an isokinetic dynamometer. It was assessed voluntary isometric contraction (MVIC), range of motion (ROM), arm circumference, muscle soreness, creatine kinase (CK), interleukin-6 (IL-6), tumor necrosis factor (TNF-?) and prostaglandin (PGE2). The MVIC, ROM, muscle soreness and arm circumference were assessed before, immediately after, 24, 48 and 72h after eccentric exercise. For the plasma activity of CK, IL-6, TNF-? and PGE2, the blood samples were made before, 24, 48 and 72 hours after the eccentric protocol. As result of the present dissertation it is presented an original article. The aim of the presented original study was to compare changes in indirect markers of muscle damage and inflammation in young and postmenopausal women after maximal eccentric exercise. Significant differences were found between groups for eccentric torque and TNF-?, with greater values for postmenopausal women (p<0.05). A positive significant correlation (p<0.05) was found between age x muscle soreness and between age x PGE2. In conclusion, these results do not support the hypothesis that postmenopausal women were more susceptible to eccentric exercise-induced muscle damage than young women / Mestrado / Atividade Fisica, Adaptação e Saude / Mestre em Educação Física

The diploma thesis deals with the mathematical modeling of high-frequency pressure pulsations in water turbines. Pulsations are caused by the interaction between stator a rotor blades. These high-frequency pressure pulsations then cause high cycle fatigue of the head cover, spiral casing, runner and distributor. The mathematical model is solved by transfer matrix method. Data are processed in F-A char and MS Excel programs. Final results are demonstrated by frequency amplitude characteristics and by pressure mode shapes, where comparison of the mathematical model with the measurement is shown.

My diploma thesis deals with the basic principle of the frequency inverter and his construnction. In the next section are analyze the basic properties and characteristics of the using equipment. The main part of this thesis is to investigate the dynamic properties of asynchronous electric motor controlled by a frequency inverter using STARTER. The results of experiments are compared and analyzed.

Kännedom om effekten av temperaturvariationer på det perifera nervsystemet ger en djupare förståelse för de fysiologiska mekanismerna som ligger till grund för funktionen av neuromuskulär påverka vid patologiskt och friskt tillstånd. Syftet med den här studien är att redogöra för hur den sensoriska nervledningshastigheten, distal latens och amplitud en i nervus medianus påverkas vid temperaturförändringar på handryggen från 26 till 33 °C. Studien omfattade 19 deltagare mellan 20–40 år. Mätningarna utfördes vid tre temperaturintervaller; kall (26–27° C), ljummen (28–29° C) och varm (32–33° C) för varje deltagare.   I denna studie observerades sensorisk nervledningshastigheten och distal latens visade ett signifikant samband med p-värde&lt;0.001. Temperaturökningen leder till ökad nervledningshastighet med 1,61 m/s/° C och distal latensen reduceras med 0,1 ms/° C. Däremot sågs inget samband mellan amplitud med p-värde=0.87 och temperaturökningen. Temperaturförändringen har en påverkan på perifera nerver, detta bör uppmärksammas vid elektroneurografisk undersökning.  Det är viktig att uppnå den standardtemperaturen (31–34°C) vid en elektroneurografisk undersökning för att ställa rätt diagnos. Vid svårigheter med att upp nå den standardtemperaturen kan en korrektionsfaktor användas. / Understanding the effect of temperature on the peripheral nervous system helps to have a better knowledge of the physiological mechanisms and functionality of the neuromuscular system. This study aimed to analyze the effect of temperature change, from 26 to 33°C at the dorsal side of the hand, on the sensory conduction velocity, distal latency, and amplitude of the median nerve. The study consists of 19 individuals between 20–40 years. The measurement was carried out at three temperature ranges: cold (26–27°C), intermediate (28–29°C), and warm (32–33°C).   Sensory conduction velocity and distal latency were significantly correlated to temperature with a p-value &lt;0.001.  Sensory nerve conduction velocity and distal latency changes by 1,61 m/s and 0.1 ms with a temperature change of 1°C, respectively. In this study, the author did not observe a significant correlation (p-value of 0.82) between temperature and amplitude due to the large variability of amplitude in the temperature range used in this study. It is important to perform electroneurographic diagnosis at a temperature of over 31-34°C, otherwise, a correction factor must be used for a reliable diagnosis.

The current thesis work is based on fatigue testing of welded structures which is completed in collaboration with Volvo CE. Improvement of the technology and customers demands for higher quality products with lower price makes the VCE to invest on the product development projects. One of the projects in VCE focuses on the weight and production cost optimization of the bogie beam on the hauler. The present project is a completion of the previous project with the objective of the fatigue testing of the bogie beam of the hauler under oscillating loads for verification of the expected fatigue life assessed with FEM. In the process of this work, an existing test rig is modified. The strains over the beam are measured through strain gauges mounted on the beam. The simulated model, the stresses and strains are investigated. The fatigue life is evaluated with different fatigue assessment methods. Finally, the outcomes of all the methods for fatigue investigation of the beam are compared and verified. / Detta examensarbete, som utförts för Volvo CE, behandlar utmattningsprov av svetsade konstruktioner. Teknikutveckling och förändrade kundkrav på högre kvalitet till en lägre kostnad är drivkrafter för Volvo CE att investera i produkt- och metodutvecklingsprojekt, som exempelvis det aktuella projektet att optimera vikt och tillverkningskostnad för boggi-balkar till dumprar. Detta projekt är en fortsättning av ett tidigare arbete som hade som mål att verifiera utmattningslivslängden för en boggibalk till en dumper predikterad med FEM, genom att utmattningsprova balken för oscillerande last. Som en del av projektet modifieras en existerande provningsrigg. Töjningar på balken mats med ett antal töjningsgivare monterade på balken. Spännings och töjningfrån den simulerade modellen analyseras och utmattningslivslängden jämförs för olika metoder för att prediktera utmattning. Slutligen jämförs och veriferas dessa metoder.

Near-field acoustical holography (NAH) has been used extensively for acoustical imaging of infinitesimal-amplitude (or small-amplitude) sources. However, recent interests are in the application of NAH to image finite-amplitude (or high-amplitude) sources such as jets and rockets. Since NAH is based on linear equations and finite-amplitude sources imply nonlinear effects, which cause shock formation and consequently an altered spectral shape, a feasibility study is carried out to determine the effect of nonlinear propagation on NAH. Jet and rocket sources typically have a distinct spectral shape resembling a ‘haystack’ and center frequencies varying from 30 to 300 Hz. To test the effect of nonlinear propagation on jet or rocket noise, several waveforms with varying spectral shapes and center frequencies were created and numerically propagated in one dimension using a nonlinear propagation algorithm. Bispectral methods were used to determine the amount and effect of nonlinearity, showing that higher center frequencies lead to more nonlinearities for a given amplitude. Also, higher-order statistical analysis of the time derivative of the waveforms was used to determine information about the relative amount of waveform steepening and shock coalescence occurring. NAH was then used to reconstruct the original waveform magnitude and the errors were determined. It was found that the ‘haystack’ spectral shape can be preserved by the nonlinear effects leading to low amplitude-reconstruction errors, whereas a narrow-band spectral shape will become altered and reconstruct very poorly. However, if nonlinear effects become strong due to higher center frequencies, longer propagation distances or higher amplitudes, even the ‘haystack’ shape will become altered enough to cause poor reconstruction. Two-dimensional propagation studies were also performed from two point sources, showing differences between linear and nonlinear propagation.

All-optical signal processing techniques for phase-shift keyed (PSK) systems were developed theoretically and demonstrated experimentally. Nonlinear optical effects in fibers, in particular four-wave mixing (FWM) that occurs via the ultra-fast Kerr nonlinearity, offer a flexible framework within which numerous signal processing functions can be accomplished. This research has focused on the regenerative capabilities of various FWM configurations in the context of processing PSK signals. Phase-preserving amplitude regeneration, phase regeneration, and phase-regenerative wavelength conversion are analyzed and demonstrated experimentally. The single-pump phase-conjugation process was used to regenerate RZ-DPSK pulse amplitudes with different input noise distributions, and the impact on output phase characteristics was studied. Experiments revealed a limited range over which amplitude noise could effectively be suppressed without introduction of phase noise, particularly for signals with intensity pattern effects. Phase regeneration requires use of phase-sensitive amplification (PSA), which occurs in nonlinear interferometers when the pump and signal frequencies are degenerate (NI-PSA), or in fiber directly through single-stage (degenerate) or cascaded (non-degenerate) FWM processes. A PSA based on a Sagnac interferometer provided the first experimental demonstration of DPSK phase and amplitude regeneration. The phase-regenerative capabilities of the NI-PSA are limited in practice by intrinsic noise conversion (amplitude to phase noise) and to a lesser extent by the requirement to modulate the pump wave to suppress stimulated Brillouin scattering (SBS). These limitations are relaxed in novel materials with higher SBS thresholds and nonlinearities. Degenerate FWM provides PSA in a traveling-wave configuration that intrinsically suppresses the noise conversion affecting the NI-PSA, while providing stronger phase-matched gain. Experiments confirmed superior phase-regenerative behavior to the NI-PSA with simultaneous reduction of amplitude noise for NRZ-DPSK signals. Phase-regenerative wavelength conversion (PR-WC) provides the regenerative properties of PSA at a new wavelength, and was proposed and demonstrated for the first time in this research. The parallel implementation of two FWM processes, phase-conjugation and frequency conversion, provides two idlers which exhibit interesting and useful regenerative properties. These were investigated theoretically and experimentally. Ideal phase-regenerative behavior is predicted when the contributing FWM processes are equally phase-matched, which can be maintained over any interaction length or wavelength shift provided the pump powers are properly adjusted. Depleted-pump regime PR-WC provides simultaneous phase and amplitude regeneration. Experiments confirmed regenerative behavior for wavelength shifts of the idlers up to 5 nm. Two techniques for phase regeneration of 4-level PSK signals were developed and evaluated. The first is based on parallel operation of PSAs suitable for processing 2-level PSK signals, where phase projection and regeneration are combined to recover the input data. Analysis of this scheme outlined the conditions required for effective phase regeneration and for practical implementation using known PSAs. A novel process based on FWM (parallel phase-conjugation followed by PSA) was developed and analyzed, and demonstrated using numerical simulations. These studies provide a basis for further work in this area.

One of two project reports. Part A can be found at: http://hdl.handle.net/11375/17932 / Time-averaged holographic interferometry is applied to the study of the resonance mode structures of an electromagnetic and a piezoelectric high frequency loud-speaker. Vibrational amplitude measurements were made using the simple concept of the holo-diagram. The vibrational amplitude sensitivity range was from 0.1 µm to 0.9 µm, which is an ideal range since the speaker vibrational amplitudes were always below 0.8 µm. Application of the technique to non-destructive speaker quality testing and optimum speaker design is also discussed in the report. / Thesis / Master of Engineering (ME)

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