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Estimation of Mercury Injection Capillary Pressure (MICP) from the Nuclear Magnetic Resonance (NMR) exponential decay with the Machine Learning (ML) Neural Network (NN) approachUgolkov, Evgeny A. 09 July 2022 (has links)
Information about the capillary pressure has a wide range of applications in the petroleum industry, such as an estimation of irreducible water saturation, calculation of formation absolute permeability, determination of hydrocarbon-water contact and the thickness of the transition zone, evaluation of the seal capacity, and an estimation of relative permeability. All the listed parameters in the combination with petrophysical features, pressures, and fluid properties allow us to evaluate the economic viability of the well or the field overall. For this reason, capillary pressure curves are of great importance for petroleum engineers working on any stage of the field development: starting from exploration and finishing with production stages. Nowadays, capillary pressure experiments are provided either in the lab on the plugs of the rocks, either in the well on the certain stop points with the formation tester tools on the wire or tubes. Core extraction and formation testing are both laborious, expensive, and complicated processes since the newly-drilled well remain in the risky uncased condition during these operations, and for this reason, usually the listed works are provided in the exploration wells only. Afterward, the properties obtained from the exploration wells are assumed to be the same for the extraction or any other kinds of wells. Therefore, these days petroleum engineers have limited access to the capillary pressure curves: the modern tests are provided on the limited points of formation in the limited number of wells. An extension of capillary pressure measurements in the continuous mode for every well will dramatically expand the abilities of modern formation evaluation and significantly improve the field operation management by reducing the degree of uncertainty in the decision-making processes. This work is the first step toward continuous capillary pressure evaluation. Here we describe the procedure of finding the correlation between the results of the lab Nuclear Magnetic Resonance (NMR) experiment and lab Mercury Injection Capillary Pressure (MICP) measurements. Both experiments were provided on the 9 core plugs of the sandstone. Afterward, a Machine Learning (ML) algorithm was applied to generate additional samples of the porous media with different petrophysical properties representing the variations of the real cores of available sandstones. Overall, 405 additional digital rock models were generated. Thereafter, the digital simulations of MICP and NMR experiments were provided on the generated database of digital rocks. All the simulations were corrected for limited resolution of the CT scan. Based on the created database of experiments, we implemented a ML algorithm that found a correlation between the NMR echo data and MICP capillary pressure curves. Obtained correlation allows to calculate capillary pressure curve from the NMR echo data. Since NMR logging may be implemented in every well in the continuous mode, an extension of the created technique provides an opportunity for continuous estimation of capillary pressure for the whole logging interval. This extension is planned as future work.
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Optimal Temperature and Catalyst Renewal Policies in a Tubular Reactor with Catalyst DecayStephanopoulos, George 09 1900 (has links)
<p> The optimal temperature and catalyst renewal policies which maximize the average profit over a free time period in a tubular reactor with uniform temperature and decaying catalyst for a single irreversible reaction, are sought.</p> <p> In addition, the optimal initial catalyst activity and the optimal total time have been studied.</p> <p> A numerical procedure together with theoretical developments is used to solve the problem for a more general performance index (average profit function) which takes into account the value of the desired product, the cost for the regeneration of the catalyst and the cost of the fresh catalyst.</p> <p> The problem is treated in the format of Pontryagin's Maximum Principle.</p> / Thesis / Master of Engineering (MEngr)
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The Ratio of the Scalar and Tensor Coupling Constants in Beta-Decay / The Ratio of the Coupling Constants in Beta-DecayZernik, Wolfgang 09 1900 (has links)
The beta-decay interaction contains two terms which consist of invariant products of two scalars and two tensors respectively. The relative absolute magnitude of these two terms is fairly well established but there has been some controversy over their relative sign. In this thesis the form of the interaction is investigated by means of an analysis of the second-forbidden decay spectrum of Cs137 and it is concluded that the relative sign of the scalar and tensor terms is negative. / Thesis / Master of Science (MS)
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Memory for temporally nonadjacent tonal centers mediated by musically salient featuresSpyra, Joanna January 2022 (has links)
Research on memory often describes the remarkable longevity of music. However, memory for music is not uniform. Cook (1987) found that participants were not able to tell apart excerpts that modulated from those that did not when the excerpt was longer than 1 minute in length. This suggests that participants were no longer able to remember, and compare, musical keys after a relatively short period of time. Farbood (2016) and Woolhouse et al. (2016) further explored the limitations of memory for tonal structures finding that, in fact, harmonic memory only lasts up to 21 seconds after modulation. However, this research was done using homophonic stimuli—arpeggios or quarter-note chords—that may not be representative of the music participants would be listening to regularly. The focus of this project was to explore how the addition of certain musical features, such as melodic or rhythmic figurations, may influence harmonic memory. Observing these possible influences may provide us with insight into the processes responsible for auditory memory and how it differs from other domains, such as speech or vision. Chapter 1 explores prominent memory literature and music cognition experiments that support, or address concerns with, common memory models. Here, I introduce a cognitive system which reconciles music research with models by memory specialists such as Baddeley and Snyder. Chapter 2 presents a detailed account of background empirical literature, including Farbood (2016) and Woolhouse et al. (2016). Though fundamental to the exploration of temporally nonadjacent harmonic memory, this research is potentially limited in its generalizability due to the homophonic nature of the stimuli. Chapter 3 explores this limitation by testing the effects of adding surface features—melodic and rhythmic components often used for elaboration in composition—on memory for large-scale tonal structures. Results found that harmonic memory is, indeed, enhanced and prolonged by these elaborative components, lasting up to 33 seconds, well past the limit found in previous research. Farbood (2016) further claimed that harmonic memory is significantly interrupted by new, highly harmonic excerpts. However, results from Woolhouse et al. (2016), Spyra et al. (2021) and those from Chapter 3 all question this claim as they employed stimuli that was highly harmonic. Chapter 4 investigates the contradiction by testing whether functional diatonic, functional chromatic, or random sequences degraded harmonic memory for an original key. Functional diatonic intervening information resulted in increased harmonic memory, directly contradicting Farbood’s original findings. In Chapter 5, these results are explored in terms of prominent memory models in the field of cognition, supporting standard models of memory such as that by Baddeley and Hitch (1974) or Atkinson and Shiffrin (1968), as well as my proposed cognitive system. This is further elaborated by discussing the process of undergoing a musical judgement task from perception through to decision-making. In summary, this project suggests that more generalizable stimuli containing realistic musical features produce a significant boost in harmonic memory. Furthermore, this arguably calls into question standard practices in analysis that categorize surface features as hierarchically less important than ’deeper’ harmonic events, and thus, potentially less important from a cognitive perspective. Which is to say, this evidence suggests that these features may play a vital role in remembering nonadjacent harmonic
structures. / Dissertation / Doctor of Philosophy (PhD) / Memory for music is often celebrated for its longevity. Music is a complex stimulus, however, and not all of its characteristics are remembered equally well. Past research has found that participants were not able to remember musical keys after a surprisingly short period of time: Farbood (2016) and Woolhouse et al. (2016) found that harmonic memory—i.e., memory for a key—lasts up to 21 seconds after a key change. Compared to nursery rhymes remembered from childhood bedtimes, this is remarkably limited. Yet this research did not fully explore which musical characteristics affect harmonic memory as it was done using simple musical stimuli: compositions made of blocks of chords. Whereas a string of chords might sound pleasant, it may not be representative of the type of music that people listen to regularly (with complex melodies and instrumentation). The focus of this project was to explore musical factors, such as melodies or rhythms, and measure how they interact with musical memory. Observing specific aspects of the stimulus gives us a window into the complexities of human memory, particularly that of the auditory domain.
Chapter 1 provides an overview of memory literature with a focus on common memory models and the musical research that supports them or contributes to their development. Here, I propose a cognitive system which integrates prominent models that otherwise describe different stages of processing complex auditory stimuli. Chapter 2 presents a detailed account of background empirical literature. This provides a basis for a series of experiments outlined in Chapters 3 and 4. These experiments investigate how components of music influence harmonic memory. Components include Surface Features, or ornamentations in music such as melodies or rhythms, and Harmony, the structure of the key itself which can make an excerpt sound more, or less, familiar. Results suggest that memory is significantly enhanced and prolonged by the addition of surface features. Furthermore, harmony that most resembles culturally familiar compositional practices also provides a memory boost when compared to random or somewhat ambiguous sequences. In Chapter 5, the implications of these results are explored with regards to the general memory models discussed in Chapter 1. Results support standard models of memory and my proposed cognitive system, as demonstrated by following the processing of my experimental musical stimuli from sound to executive function. This project suggests that more complex and musically realistic stimuli produce a significant memory boost. This puts into question traditional practices in music analysis which separate surface features into hierarchically less important positions when, in fact, the musical surface may be vital to our processing of auditory stimuli.
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Measurement of the Michel Parameter Rho Using the MEGA Positron SpectrometerLee, Fei-sheng 29 April 2001 (has links)
This experiment attempts to measure the Michel parameter Rho in normal muon decay Mu to e nu_{e} nu_{mu} with a precision of 0.001. The Standard Model with pure V-A interaction gives 0.75 for this parameter. The world average value is 0.7518 +/- 0.0026. A deviation of the value of Rho from 0.75 will indicate new physics.
The experiment, RHO, was carried out at the Los Alamos Meson Physics Facility (LAMPF) of Los Alamos National Laboratory (LANL) in New Mexico, USA, in 1993. The existing experimental set-up that was built for the MEGA experiment was used for the RHO measurement. The experiment was a collaboration of about 50 physicists from Los Alamos National Laboratory, Stanford University, Fermi National Accelerator Laboratory, Virginia Tech, Texas A University, Indiana University, Valparaiso University, University of Houston, University of Chicago and University of Virginia.
The result of the experiment is in agreement with Standard Model. The precision of this measurement was dominated by systematic uncertainties due to the fact that the positron spectrometer used in the measurement was designed for another experiment. Thus, the data analysis here focused mainly on the determination of systematic errors. / Ph. D.
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Analysis of Neutral D Meson Two-Body Decays to a Neutral Kaon and a Neutral PionKimmel Jr, Taylor Douglas 15 September 2021 (has links)
Decays of neutral D mesons to final states containing K + π's could provide evidence for CP-violation from a source not accounted for in the Standard Model. Due to the interference between Cabibbo-favored and Cabibbo-suppressed transitions, a decay rate asymmetry of D0 → K0S π0 compared to D0 → K0Lπ0 has been predicted to be non-zero. If New Physics interferes in doubly Cabibbo-suppressed D decays, the measurement of this asymmetry would differ from the predicted value and may provide evidence for CP-violation beyond the CKM mechanism. I present an analysis method to measure this branching fraction asymmetry, R(D0) ≡ B(D0→K0S π0)−B(D0→K0L π0)/(B(D0→K0Sπ0)+B(D0→K0Lπ0)), utilizing e+e− → cc events in the Belle dataset. / Doctor of Philosophy / The Universe appears to be made almost entirely of matter rather than antimatter; however, matter and antimatter should have been created in equal amounts in the Big Bang. We do not know exactly why we observe so much more matter as compared to antimatter. The Standard Model (SM) of particle physics accounts for some of the asymmetry through Charge-Parity (CP) symmetry violation, which explains how particles behave differently than their corresponding antiparticles. In the current state of the SM, some CP-violation is allowed in decays via the weak force, but the theory does not account for enough CP violation to explain the amount of matter-antimatter asymmetry observed in the Universe. Decays of a D meson to a kaon (K meson) plus one or more pions (π mesons) via a new mechanism beyond the weak force could provide evidence of a new source of CP-violation. In this analysis, I present a method for analyzing the decays of neutral D mesons to a neutral kaon and a neutral pion in the Belle dataset to test the SM.
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Coarse Woody Debris in Industrially Managed Pinus taeda Plantations of the Southeastern United StatesPittman, Judd R. 25 August 2005 (has links)
Coarse woody debris (CWD) plays an influential role in forested ecosystems by adding organic matter to soils, stabilizing the soil environment, providing wildlife habitat, preventing soil erosion, providing seedling establishment habitat, and involvement in the nutrient cycle. Most CWD research has been conducted in old-growth and unmanaged, second-growth forests. However, less is understood about CWD in intensively managed ecosystems, such as industrialized southern pine plantations. The objectives of this study were to determine the climatic and ecological factors that affect the decomposition rate of CWD, to predict the decomposition rate, specific gravity, and time since death (TSD) using multiple linear regression in industrial loblolly pine (Pinus taeda L.) plantations in the southeastern United States. The study sites for this project were part of a long-term, loblolly pine thinning study maintained by the Loblolly Pine Growth and Yield Research Cooperative at Virginia Tech. Measurements included piece size, position, and decay class. Samples of CWD were collected and analyzed to determine their mass and density. Decomposition rate of CWD was significantly different across position classes and decay classes: disk decomposition rates were significantly negatively correlated with disk diameter, large and small end piece diameter, estimated disk height, and disk dry weight. Average annual precipitation and average annual temperature were not significantly correlated with CWD disk decomposition rate. / Master of Science
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The VenueWilliams, James 01 April 2024 (has links) (PDF)
When an aspiring interior designer embattled with insecurity about her dirt poor upbringing becomes enamored with her fiancé's family estate–the wedding venue–she finds herself embroiled in the literal rot and decay festering within the dream location after visions of a ghost threaten her fairytale ending.
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Development of a high-pressure xenon gas time projection chamber and evaluation of its performance at around the Q value of ???Xe double-beta decay / 高圧キセノンガスタイムプロジェクションチェンバーの開発および???Xeの二重ベータ崩壊Q値付近におけるその性能評価Yoshida, Masashi 25 March 2024 (has links)
京都大学 / 新制・課程博士 / 博士(理学) / 甲第25115号 / 理博第5022号 / 新制||理||1716(附属図書館) / 京都大学大学院理学研究科物理学・宇宙物理学専攻 / (主査)教授 中家 剛, 教授 田島 治, 准教授 WENDELLRoger / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DFAM
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Regulation of lymphoid-myeloid lineage bias through Regnase-1/3-mediated control of Nfkbiz / Regnase-1/3によるNfkbiz発現調節を介したリンパ球-骨髄球の系譜決定制御Yamada, Shinnosuke 25 March 2024 (has links)
京都大学 / 新制・課程博士 / 博士(医科学) / 甲第25205号 / 医科博第161号 / 新制||医科||11(附属図書館) / 京都大学大学院医学研究科医科学専攻 / (主査)教授 生田 宏一, 教授 伊藤 貴浩, 教授 齋藤 潤 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DFAM
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