The development of reliable, affordable, and efficient sensors is a key step forward in providing tools for efficient monitoring of critical environmental parameters. Fiber-optic sensors are already widely used in various industrial sensing fields. They have proven themselves reliable in harsh environments and can measure different physical quantities, such as temperature, pressure, strain, refractive index (RI), and humidity. Fiber-optic Mach-Zehnder Interferometer (MZI) is a well-studied optical fiber interferometer that has proven capacity for sensing ambient refractive index. In this dissertation, we present Fiber Bragg grating (FBG) embedded in a microfiber Mach-Zehnder Interferometer designed for sensing temperature and refractive index. The MZI is constructed by splicing a short length of 40-μm-diameter microfiber between standard single mode fibers. A one-millimeter-long FBG is then written in the microfiber using a direct, point-by-point, ultrafast laser inscription method. The microfiber MZI shows only moderate sensitivity to ambient refractive index and temperature changes. In contrast, the microfiber FBG is insensitive to ambient refractive index change, while it exhibits typical sensitivity to temperature variation. These distinct characteristics of the FBG and MZI sensors enable the simultaneous measurement of refractive index and temperature as well as temperature compensation in ambient refractive index measurement. Further, we report the use of a fiber-optic Mach-Zehnder Interferometer to measure core refractive index changes written by femtosecond laser irradiation. The core-offset interferometer was constructed by splicing a lightly misaligned stub of standard single-mode fiber between the device’s lead-in and lead-out optical fibers. When the core refractive index of an in-fiber interferometer is altered, that process changes the phase of the core light. Since the phase of light propagating in the cladding (reference arm) remains unchanged, the transmission fringe pattern of the interferometer undergoes a spectral shift. In the present research, that spectral shift was used to quantify the effective core refractive index change in a standard single-mode fiber. In addition, we designed and developed a custom flame-based tapering machine that is used to fabricate miniaturized Mach–Zehnder interferometers (MZIs) using sharply tapered photonic crystal fiber (PCF). This technique produces sensors capable of highly sensitive ambient refractive index (RI) measurements. The sensor is fabricated by fusion splicing a small stub of PCF between standard single-mode fibers with fully collapsed air holes of the PCF in a splicing region. Tiny flame geometry enables the sharp tapering of the PCF, resulting in a short fiber length and high RI sensitivity. It appears that sharp tapering has a great impact on RI sensitivity enhancement, when compared with methods that decrease taper waist diameter. The tapering technique is further used to construct the Mach-Zehnder Interferometer-based fiber-optic refractive index (RI) sensor by uniformly tapering standard single mode fibers (SMF) for RI measurement. The fabricated MZI device does not require any splicing of fibers and shows excellent RI sensitivity. / Graduate

The purposes of this dissertation were to 1) determine what tapering and peaking practices appear to be most effective via systematic review, 2) to identify the tapering and peaking practices used by North American powerlifters, 3) to experimentally compare muscular adaptations and performance changes following two different training cessation periods, and 4) to experimentally compare the two most common taper models following a training program aimed at peaking maximal strength. Based on the scientific literature, a step and exponential taper appeared to be the most effective tapering models used when volume-load is reduced by half over 2±1 week. Interestingly, North American powerlifters reported that the step taper was most often used while reducing volume-load by 41-50% over 7-10 days. Furthermore experimentally, there were no changes in lower body maximal strength following 3 or 5 days of training cessation. However, upper body maximal strength decreased following 5 days of training cessation. Thus, at the end of a taper, a training cessation period of 3 days appears to be effective for maintaining upper and lower body maximal strength. Furthermore, a work-matched step taper and exponential taper produced similar outcomes for 1RM back squat, bench press, and deadlift, powerlifting total and Wilks Score in strength athletes, yet deadlift 1RM changes favored the exponential taper. However, there were clear physiological differences observed at the whole muscle and muscle fiber levels that appeared to contribute to performance outcomes. This was one of the first investigations demonstrating whole muscle and muscle fiber hypertrophy following a peaking program in strength athletes. Immunohistochemical and immunoblotting analyses demonstrated an increase in myosin-heavy chain IIA content with concomitant decreases in myosin-heavy chain I and IIX content, particularly following the step-taper. These myosin isoform shifts towards a faster, higher quality phenotype were related to changes in underlying myocellular signaling (i.e. Sox6 upregulation, micro RNA-499a downregulation) responsible for fiber-type transitions. These findings indicate a shorter taper may produce favorable muscular adaptations followed by a period of short-term training cessation to prevent the loss of taper-induced performance adaptations. Overall, the findings from these investigations support the use of tapering to enhance maximal strength.

Phased array systems present desirable antenna features like beam steering and high gain. However, due to their high cost, civilian applications cannot generally afford them, restricting their usage to military. Hardware involved in phased array systems is expensive and the number of devices is high, since there is usually one device of each kind (filter, amplifier, shifter..) for each individual antenna. Alternative techniques, mainly based on TDMA, have been developed looking for lowering the number of elements in the system. However, these approaches increase the system bandwidth, multiplying it by a factor of $N$ (Number of antennas), as they use redundant information. In this thesis, a novel phased receiver, based on an economic sampling scheme is proposed. All the elements in an array receive a common information (signal amplitude) and a unique information (relative delay between elements). The idea is to sample only the information required to reconstruct the transmitted signal and discard the redundant one. This idea is achieved by sampling just one antenna during each RF cycle and then gathering all the information taking in account the relative delay between different antenna elements. The proposed technique is mathematically proved and validated by simulation. As a first approach, the equation for the received signal in the frequency domain is derived for a linear array. The radiation pattern and the received signals are simulated for equally spaced planar and linear arrays. Bandwidth signal transmission is demonstrated and tapering effects are shown. After that, the proposed technique is expanded for arbitrary structures and the resulting system bandwidth is enhanced by using different sampling order sequences. / Master of Science

京都大学 / 新制・課程博士 / 博士(社会健康医学) / 甲第24808号 / 社医博第132号 / 新制||社医||12(附属図書館) / 京都大学大学院医学研究科社会健康医学系専攻 / (主査)教授 川上 浩司, 教授 西浦 博, 教授 平井 豊博 / 学位規則第4条第1項該当 / Doctor of Public Health / Kyoto University / DFAM

In sports, peaking phases are often applied prior to important competitions. Peaking phases typically consist of a planned overreach followed by a taper ending with a few days of complete rest. However, during peaking phases, components of body composition such as body mass (BM), fat mass (FM), fat-free mass (FFM), and skeletal muscle mass (SMM) have been shown to be negatively impacted, which could compromise performance outcomes. Thus, the purpose of this study was to monitor body composition prior to and immediately after a peaking phase to determine if body composition changes occurred. Twelve powerlifters completed a seven-week training protocol designed to peak powerlifting performance. The first four weeks consisted of strength training designed to standardize participant training prior to the first testing session (T1). Following T1, the participants performed a one-week overreach followed by a one-week step-taper ending with 2 and 4 days of complete rest followed by a second testing session (T2). Each testing session consisted of a) measuring BM, FM, FFM, and SMM via bioelectrical impedance, and b) 1-repetition maximum (1RM) testing on back squat (BS), bench press (BP), and deadlift (DL). 1RM performances were summed together for a Powerlifting Total (PT), and Wilks Scores were applied to determine relative performance changes. There were no statistically significant changes in BM (p > 0.99), FM (p > 0.99), FFM (p > 0.99), or SMM (p > 0.99), suggesting a maintenance of body composition during the peaking phase. There were, however, statistically significant changes in 1RM-BS (p = 0.04), PT (p = 0.05), and Wilks Score (p = 0.02). These data suggest that two-week peaking phase can result in the maintenance of body composition alongside improvements in strength performance.

Doctor of Philosophy / Department of Statistics / Juan Du / Spatio-temporal and/or multivariate dependence naturally occur in datasets obtained in various disciplines; such as atmospheric sciences, meteorology, engineering and agriculture. There is a great deal of need to effectively model the complex dependence and correlated structure exhibited in these datasets. For this purpose, this dissertation studies methods and application of the spatio-temporal modeling and multivariate computation. First, a collection of spatio-temporal functions is proposed to model spatio-temporal processes which are continuous in space and discrete over time. Theoretically, we derived the necessary and sufficient conditions to ensure the model validity. On the other hand, the possibility of taking the advantage of well-established time series and spatial statistics tools makes it relatively easy to identify and fit the proposed model in practice. The spatio-temporal models with some ARMA discrete temporal margin are fitted to Kansas precipitation and Irish wind datasets for estimation or prediction, and compared with some general existing parametric models in terms of likelihood and mean squared prediction error. Second, to deal with the immense computational burden of statistical inference for multi- ple attributes recorded at a large number of locations, we develop Wendland-type compactly supported covariance matrix function models and propose multivariate covariance tapering technique with those functions for computation reduction. Simulation studies and US tem- perature data are used to illustrate applications of the proposed multivariate tapering and computational gain in spatial cokriging. Finally, to study the impact of weather change on corn yield in Kansas, we develop a spatial functional linear regression model accounting for the fact that weather data were recorded daily or hourly as opposed to the yearly crop yield data and the underlying spatial autocorrelation. The parameter function is estimated under the functional data analysis framework and its characteristics are investigated to show the influential factor and critical period of weather change dictating crop yield during the growing season.

Opioids are used routinely in the pediatric intensive care population for analgesia, sedation, blunting of physiologic responses to stress, and safety. In children, physical dependence may occur in as little as two to three days of continuous opioid therapy. Once the child no longer needs the opioid, the medications are reduced over time. A review of the literature revealed that the majority of the published studies used either a neonatal opioid assessment tool or no assessment tool. A subsequent international survey of pediatric providers found a wide range of opioid tapering practices and sporadic use of opioid withdrawal instruments to guide practice. Since tapering routines vary among practitioners, it is not uncommon to see signs and symptoms of opioid withdrawal. A prospective, descriptive study was conducted to describe the frequency of opioid withdrawal signs and symptoms and to identify factors associated with these opioid withdrawal signs and symptoms. The sample of 25 was drawn from all patients, ages 2 weeks to 21 years admitted to the Children’s Hospital of Richmond Pediatric Intensive Care Unit (PICU) and who have received continuous infusion or scheduled opioids for at least 5 days. Data collected included: opioid withdrawal score (WAT-1), opioid taper rate (total dose of opioid per day in morphine equivalents per kilogram [MEK]), pretaper peak MEK, pretaper cumulative MEK, number of days of opioid exposure prior to taper, and age. Out of 26 enrolled participants, only 9 (45%) had opioid withdrawal on any given day. In addition, there was limited variability in WAT-1 scores. The most common symptoms notes were diarrhea, vomit, sweat, and fever. For optimal opioid withdrawal assessments, clinicians should use a validated instrument such as the WAT-1 to measure for signs and symptoms of opioid withdrawal. Further research is indicated to examine risk factors for opioid withdrawal in children.

Neste estudo o objetivo foi avaliar modelos de taper para descrever o perfil do fuste de Corymbia citriodora. Os dados utilizados foram obtidos de um plantio comercial localizado na região Sul do estado do Tocantins. Foram utilizados dados de 24 árvores de Corymbia citriodora cubadas rigorosamente com medições de diâmetros nas posições do fuste: 0,2; 0,4; 0,7; 1,3; 2,70 m e, sucessivamente, de 2 m em 2 m até um diâmetro em torno de 3 cm com casca. Foram testados 44 modelos de taper, sendo 25 lineares e 19 não lineares. Na avaliação destes modelos, considerou-se a análise da distribuição de resíduos, e a estatísticas: erro padrão da estimativa, coeficiente de determinação, delineamento em blocos casualizados com arranjo de parcelas subdivididas, desvio absoluto médio, raiz quadrada do erro médio, soma de quadrados dos resíduos, desvio padrão das diferenças, critério de informação de Akaike. O modelo com melhor desempenho foi um do tipo expoente-forma ajustado na forma não linear. Após definido este melhor modelo, desenvolveu-se o método da altura relativa para simular uma cubagem rigorosa a fim de proceder ao seu ajuste e comparação com o ajuste obtido por meio de uma cubagem rigorosa real. Nesta comparação utilizaram-se os critérios estatísticos: desvio médio, bias, correlação linear, erro padrão da estimativa, entre valores observados e estimados, precisão, obtida pelo teste de qui-quadrado e raiz quadrada do erro, além de análise da distribuição dos resíduos. Concluiu-se que o uso de uma cubagem simulada pelo método da altura relativa estima bem uma equação de taper como a que se obtém pelo uso de dados reais. / In this study, evaluate the control models to describe the profile of the Corymbia citriodora. The data used are obtained from a commercial plant located in the southern region of the state of Tocantins. There are data from 24 Corymbia citriodora trees accurately cubed with diameter measurements in stem families: 0.2; 0.4; 0.7; 1,3; 2.70 m and, successively, from 2 m in 2 m to a diameter of around 3 cm in shell. 44 taper models were tested, being 25 linear and 19 nonlinear. In the evaluation of these models, we consider an analysis of the distribution of residues, and statistics: standard error of estimation, coefficient of determination, randomized block design with split plot arrangement, mean absolute deviation, square root of mean error, sum of squares of residuals, standard deviation of the differences, Akaike's information criterion. The bestperforming model for an exponent-shape fit type adjusted in nonlinear form. This version has a long list of corrections, changes, and new developments that significantly improve functioning. In this comparison, statistical criteria are used: mean deviation, bias, linear correlation, standard error of the estimate, between observed and estimated values, precision, obtained by square test and square root of error, as well as analysis of distribution and residues. It was concluded that the use of a cube simulated by the method of elevation of the estimate, as well as a conciliation equation as one obtains by the use of real data.

No description available.

Multiples in seismic data pose serious problems to seismic interpreters for both AVO studies and interpretation of stacked sections. Several methods have been practiced with varying degrees of success to suppress multiples in seismic data. One family of velocity filters for demultiple operations using Radon transforms traditionally face challenges when the water column is shallow. Additionally, the hyperbolic Radon Transform can be computationally expensive. In this thesis, I introduce a novel multiple suppression technique in the t-x-p domain, where p is the local slope of seismic events that aims at tackling some of the aforementioned limitations, and discuss the advantages and scope of this approach. The technique involves essentially two steps: the decomposition part and the suppression part. Common Mid-Point (CMP) gathers are taken and transformed from the original t-x space to the extended t-x-p space and eventually to the t0-x-p space, where t0 is the zero offset traveltime. Multiplication of the gather in the extended space with Gaussian tapering filters, formed using the difference of the powers of the intrinsically calculated velocities in terms of t0 , x and p using analytical relations and the picked primary velocities and stacking along the p axis produces gathers with multiples suppressed. / text