VictorJuiz/thesis huggingface dataset:
A Feasibility Study of In Situ Combustion for the C Zone of the Buracica Field, Brazil

The Buracica Field is located in the Reconcavo Basin, 60 mi southwest of Salvador city, capital of Bahia state, in Brazil. It was discovered in 1960. The Buracica field is divided into four blocks (East Block, West Block, North Block, and Main Block) by tv;o geological faults as shown on the map on figure 1. It contains seven producing zones: A, I3, C, D, E, F, and G. Figure 2 presents a rough schematic of the oil zones of the field. Zones C, E, and G are the main oil producing zones. The other zones A, B, D, and F are shaly sands. Zones A and B are not producers, but zones D and F produce oil in a few wells or the Main Block. The well spacing is ten acres. The production wells are completed with pumping units and produce a dead oil from all producing zones, commingled. The original water saturation was 23 percent, p.v. Water flooding has been applied to the Main Block and Last Block since 1970. The North Block is small, 150 acres, and no secondary recovery technique has been used in it. The C zone is a friable sand., and it is considered the best producing zone of the field. Table 1 presents the properties of the C zone in the North Block of Buracica field, and Table 2 presents the sand size analysis of the C zone in the Main Block. The In Situ Combustion process is a well-known thermal oil recovery process. It is suitable for shallow reservoirs with porosities in the order of 20 percent or more, high permeabilities, and oil gravities a.s high as 40 %PI. An In Situ Combustion Pilot Field Test was proposed for the C zone of the North Block of the Buracica field for the following reasons: 1) The reservoir properties presented in Table 1 satisfy the conditions mentioned above. 2) It is a small field (150 acres), and no other secondary success, the of failure, recovery technique has been utilized in it. In case of process could be extended to the other Blocks. In case no damage would be done to the other blocks. 3) The expected. oil recovery using In Situ Comb1 be high ranging from 30% to 80% of the oil in place.

Keywords:  Department of Petroleum Engineering
School of Earth Energy &amp; Environmental Sciences
Thesis
Advisor: Ramey Jr. Henry J.
The Isothermal Compressibility of Natural Gases

During the use of a new correlation for the compressibility of sweet and sour natural gases, it was noticed that an alternate form was possible. This new form suggested a more compact and direct correlation than the one available from the earlier work of Trube, or the recent study by Mattar, et. al. For manual calculations of the coefficient of isothermal compressibility, a curve which represents the dimensionless number C P as a function of pseudo-reduced temperature and pressure was prepared. The results have been extended to reduced pressures of 30, and reduced temperatures as high as 3. Finally, the adjustment method of Wichert and Aziz, is included to adjust the pseudo-critical pressure and temperature to permit use of this correlation for sour natural gases.

Keywords:  Department of Petroleum Engineering
School of Earth Energy &amp; Environmental Sciences
Thesis
Advisor: Ramey Jr Henry J.
Standing Marshall B.
The Real Gas Pseudo-Pressure for Geothermal Steam

Physical properties o f geothermal steam mixtures were compiled as functions of pressure, temperature and composition. Specifically, these properties were ones which relate to isothermal fluid flow in porous media: viscosity, gas deviation factor, and compressibility. Using this information, the real gas pseudo-pressure function, m(p), was numerically evaluated for geothermal steam.Results are presented in the form of tables, graphs, and curve fit equations over the normal range of conditions found in geothermal reservoirs. Tables and equations are computed in both International and Engineering unit systems.At pressures below 130 psia (approximately), physical properties and the real gas pseudo-pressure exhibit behavior close to that which would be expected for an ideal gas, However,over the normal range of reservoir pressures, these values depart from ideal gas behavior. A substantial error might be incurred if reservoir pressure data is analyzed assuming the validity of the perfect gas law. As most reservoirs contain only small amounts of non-condensable gases, it is reasonable t o assume that geothermal steam behaves as pure steam. However, in cases of unusually high carbon dioxide concentration, it is necessary to adjust the physical properties and the real gas pseudo-pressure of the steam mixture.

Keywords:  Department of Petroleum Engineering
School of Earth Energy &amp; Environmental Sciences
Thesis
Advisor: Atkinson Paul G.
An Evaluation of the Capacitance Probe as a Technique for Determining Liquid Saturations in Laboratory Flow Experiments

Of all the methods reported to date, the capacitance probe comes closest to meeting the constraints of measuring liquid saturations of cores at high temperatures and pressures (i.e. 250C and 500 psi). Changes in liquid saturation in the inner 4 inches of porous core are reflected in a one to four percent change in the resonant frequency of the probe. The higher the temperature at which the measurement takes place, the smaller the change for a given change in liquid saturation. The depth of penetration of the probe is only about one sixth the core thickness, and the properties of the core must be uniform throughout for the measurements to be meaningful.

Keywords:  Department of Petroleum Engineering
School of Earth Energy &amp; Environmental Sciences
Stanford Geothermal Program
Thesis
Advisor: Ramey Jr. Henry J.
A Study of Liquid Saturation Ahead of the Burning Front In Forward Combustion Oil Recovery

With discovery rates for new reserves dropping steadily, and demand for crude oil continuing to grow, it seems that the greatest need is for improved oil-recovery methods to produce the large reserves of so-called "unrecoverable" oil whose location is already known . There are some technical factors that control the rate and ultimate amount of oil recovery. The two primary ones are the permeability of the reservoir rock and the nature of the displacement mechanism. The operating examples relating to the former are fracturing and acidizing, while the latter category includes water flooding, gas repressuring, miscible flooding, and thermal recovery.

Keywords:  Department of Petroleum Engineering
School of Earth Energy &amp; Environmental Sciences
Thesis
Advisor: Ramey Jr.
An Investigation of Oil Recovery in Underground Combustion

The purpose of this experiment was to obtain laboratory data to investigate oil recovery in underground combustion. Underground, or In Situ combustion, is a secondary oil recovery process which consists of igniting the oil in a porous rock by means of an ignitor, and driving a combustion zone through a reservoir rock by means of air and/or combustion gases. The heat generated serves to increase the mobility of the oil, permitting its displacement to producing wells.There are two types of combustion processes: (1) forward combustion, in which the burning front moves from the injection well toward the production well(s). (2) reverse combustion, in which the burning front moves from the producing well towards the injection well, countercurrent to the injected air.A considerable amount of work has been done on the forward combustion oil recovery process, and numerous investigators have reported the results of laboratory combustion-tube studies, as well as experimental results from field tests. As a result, the engineering parameters of the combustion process are reasonably well known. Engineering data needed to evaluate the process include the amount of air required per barrel of oil recovered, minimum injection rates which will support combustion, total air requirement, produced fluid gas-oil ratios, oil produced, fuel requirements, and saturation distributions. The present laboratory experiment also provides these data.Details concerning the design, construction, and operation of the combustion tubes are rare. The experiments done by Mandel and Gringarten were followed closely in this report. Actually, portions of the same equipment were used.Combustion tubes used by various investigators vary in size, length, and mode of operation. Therefore, one purpose of this experiment is to present considerations important to construction and operation of a combustion tube.

Keywords:  Department of Petroleum Engineering
School of Earth Energy &amp; Environmental Sciences
Thesis
Advisor: Ramey Jr. Henry J.
Digital Twins as Testbeds for Iterative Simulated Neutronics Feedback Controller Development

Before a new nuclear reactor design can be constructed and operated, its safety must bedemonstrated using models that are validated with integral effects test (IET) data. However, because scaled integral effects tests are electrically heated, they do not exhibit nuclear reactor feedback phenomena. To replicate the nuclear transient response in electrically heated IETs, we require simulated neutronics feedback (SNF) controllers. Such SNF controllers can then be used to provide SNF capabilities for IET facilities such as the Compact Integral Effects Test (CIET) at the University of California, Berkeley (UC Berkeley). However, developing SNF controllers for IET facilities is non-trivial. To expedite development, we present the use of Digital Twins as testbeds for iterative SNF controller development. In particular, we use a Digital Twin of the Heater within CIET as a testbed for SNF Controller Development. This Digital Twin with SNF Capabilty is run as an OPC-UA server and client written almost entirely in Rust using Free and Open Source (FOSS) code. We then validate the Digital Twin with experimental data in literature. We also verify the transfer function simulation and Proportional, Integral and Derivative (PID) controllers written in Rust using Scilab. Moreover, we demonstrate use of data driven surrogate models (transfer functions) to construct SNF controllers in contrast to using the traditional Point Reactor Kinetics Equations (PRKE) models with the hope that they can account for the effect of spatially dependent neutron flux on reactor feedback. To construct the first surrogate models in this work, we use transient data from a representative arbitrary Fluoride Salt Cooled High Temperature Reactor (FHR) model constructed using OpenMC and GeN-Foam. Using the Digital Twin as a testbed, two design iterations of the SNF controller were developed using the data driven surrogate model. Compared to the potential development time taken in using physical experiments, using the digital twin testbed for SNF controller development resulted in a significant time saving. We hope that the approaches used in this dissertation can expedite testing and reduce expenditure for licensing novel Gen IV nuclear reactor designs.

Advisor: Peterson, Per F
Adaptive cellular strategies to improve commodity chemical production in Escherichia coli

Biology holds an amazing propensity for chemistry. Living systems continuously carry out a vast plethora of chemical reactions within a complex network, known as metabolism, to sustain growth and improve evolutionary fitness. Metabolic engineers seek to utilize this aptitude for chemistry by creating biological catalysts for chemical production from renewable feedstocks. Biological catalysts offer an eco-friendly, and in some cases, superior, alternative to petrochemical-based chemical production.In this work, we examine biological catalysts designed for the production of two C4 commodity chemicals, n-butanol and (R)-1,3-butanediol. These catalysts are strains of Escherichia coli containing constructed biosynthetic pathways. Leveraging an anaerobic growth selection, laboratory adaptive evolution identified several mutant strains with improved phenotypes. We set out to understand the mechanism by which these adaptive mutations confer improved production. Through detailed analysis of n-butanol fermentation, we discovered that the parent strain for our evolution was unable to support sustained anaerobic growth via n-butanol fermentation, potentially due to metabolic burden associated with overexpression of the pathway enzymes. Further experimentation suggested that the mutations arose as a strategy to relieve metabolic burden through decreased expression of our biosynthetic pathway. The results of this study highlight the importance of balanced pathway expression when designing biological catalysts. We then shifted our focus to design a microbial catalyst for production of polyhydroxyalkanoates (PHAs) containing unsaturated monomers. Sites of unsaturation provide functional handles for downstream chemical modification. We devised a metabolic strategy to convert two non-canonical amino acids with unsaturated functional groups to their respective 2-hydroxy acids and activate these acids as coenzyme A thioesters for polymerization within E. coli. We identified and tested candidate enzymes for the appropriate activities in vitro and successfully showed that our identified enzymes can form a functional biosynthetic pathway. These experiments lay the groundwork for creation of a microbial catalyst capable of generating PHAs with unsaturated functional groups using glucose as a carbon source.

Advisor: Chang, Michelle C.Y.
Photorealistic Reconstruction from First Principles

In computational imaging, inverse problems describe the general process of turning measurements into images using algorithms: images from sound waves in sonar, spin orientations in magnetic resonance imaging, or X-ray absorption in computed tomography.Today, the two dominant algorithmic approaches for solving inverse problems are compressed sensing and deep learning. Compressed sensing leverages convex optimization and comes with strong theoretical guarantees of correct reconstruction, but requires linear measurements and substantial processor memory, both of which limit its applicability to many imaging modalities. In contrast, deep learning methods leverage nonconvex optimization and neural networks, allowing them to use nonlinear measurements and limited memory. However, they can be unreliable, and are difficult to inspect, analyze, and predict when they will produce correct reconstructions./nIn this dissertation, we focus on an inverse problem central to computer vision and graphics: given calibrated photographs of a scene, recover the optical density and view-dependent color of every point in the scene. For this problem, we take steps to bridge the best aspects of compressed sensing and deep learning: (i) combining an explicit, non-neural scene representation with optimization through a nonlinear forward model, (ii) reducing memory requirements through a compressed representation that retains aspects of interpretability, and extends to dynamic scenes, and (iii) presenting a preliminary convergence analysis that suggests faithful reconstruction under our modeling.

Advisor: Recht, Benjamin
Solar Flux: Remaking landscapes, labor, and environmental politics in California

From 2015-2020, massive booms in solar power and high speed rail reconstructed landscapes across California's San Joaquin Valley. Globally rare alliances of construction unions with environmental justice and immigrant movements won breakthroughs in regional politics. How did construction workers reshape their power in response to the booms–and what formed their politics in this extraordinary direction? This dissertation argues that construction worker power hinged on unions' capacity to reproduce the workforce for urgent landscape transformations, while labor alliances were driven by shared political exclusion and common household struggles over social reproduction of the region's working class, Mexican-American majority. Drawing on five years of ethnographic and archival research, I compare the Fresno-Madera region, where these construction labor-immigrant-environmental justice alliances prevailed at crucial moments, to the Bakersfield region just to the south, where limited household ties, unstable overall employment, and conflicts over oil fractured potential coalitions. In conversation with environmental justice, Marxist feminist, and Marxist geography approaches–including Gramscian interpretations of Clyde Woods, Ruth Wilson Gilmore, and Matthew Huber–I develop a theory of environmental leverage, explaining how landscape transformation and the labor involved can challenge or entrench hegemony. The breakthroughs made by San Joaquin alliances in winning municipal office, jobsite power, and infrastructure redistribution help show how working and oppressed people can build pressing climate transitions by their own blueprints.

Advisor: Chari, Sharad
Sayre, Nathan
Inferring species distributions from semi-structured biodiversity observations

Estimating the spatiotemporal distributions of species and understanding how variation in those distributions is explained by the environment are central goals in ecology. Observations of animals generated by participatory science (or "citizen science") are an increasingly important resource for ecologists interested in estimating species distributions because they are high-volume and high-resolution. However, statistical inference with these data is more challenging than inference with data collected under standardized sampling, because participatory science observations contain substantial unmeasured variation in sampling effort and observer behavior. Ecologists need tools and methodological guidance that support the estimation of computationally efficient, flexible statistical models useful for robust inference with participatory science data. In this dissertation, I advance the field of species distribution modeling with participatory science data via contributions across three chapters. First, I present a new software tool, nimbleEcology, that supports the efficient and flexible estimation of hierarchical ecological models, alongside a brief review of the use of such models in ecology and three worked examples of model estimation. Second, I undertake a comparison of two modeling approaches useful for estimating relative abundance from participatory science data, making practical recommendations for model selection. Finally, I apply these methodological developments to data obtained from an important participatory science dataset, eBird, to investigate how common birds respond to drought in California's Central Valley ecoregion. This project demonstrates the application of modeling principles to an important ecological case study and produces new evidence to characterize critical dimensions of birds' drought responses.

Advisor: de Valpine, Perry
Results on Unlikely Intersection Problems

This dissertation is concerned with problems related to unlikely intersections and is divided into three parts. The first part consists of background about unlikely intersection problems, with particular emphasis on the Andre–Oort conjecture and existential closedness problems. These problems will be the central focus of the subsequent parts. In the second part, wegive an explicit formula for heights of special points on quaternionic Shimura varieties using Faltings heights of CM abelian varieties. Special points are associated to CM-fields E and partial CM-types ϕ ⊂ Hom(E,C). We show that this quaternionic height is compatible with the canonical height of a partial CM-type given by Pila, Shankar, and Tsimerman. By doing so, we give another proof showing that the height of partial CM-types is bounded in terms of the discriminant of E. This height bound is a crucial ingredient in proving the Andre–Oort conjecture for general Shimura varieties. The third part is about the intersection of algebraic varieties with the graph of transcendental functions. Let q : Ω → S be the uniformization map of a Shimura variety. We prove two results that give geometric conditions for when an algebraic variety V ⊂ Ω×S contains a Zariski dense subset of points of the form (x, q(x)).

Advisor: Yuan, Xinyi
Olsson, Martin
The "Secret Inclination" of the German Weak Masculine Nouns: A Case of Usage-Driven Paradigmatic Change. A Diachronic Corpus Study (1350–1900).

Over the course of the Early New High German (ENHG) period (ca. 1350–1650), the German inflectional system underwent significant restructuring. Among the affected Middle High German (MHG) inflectional classes was a class of masculine nouns traditionally labeled “weak,” defined by the presence of the ending -(e)n in all forms except the nominative singular, which usually ended in -e. In the modern language (New High German [NHG]), the nouns that once belonged to this class are spread out across at least four inflectional classes: one group of nouns (Group 1), most denoting people and large animals, has remained in the weak masculine class, while in each of three other groups (Groups 2–4), the paradigm has been rebuilt with a different part of the original weak paradigm as its base.This corpus study explores the causes of these changes through the lens of a usage-based framework, proceeding from the hypothesis that high token frequency renders word forms more resistant to analogical change, while low token frequency leaves them vulnerable to loss and replacement. It traces the diachronic paths of 37 current and former members of the weak masculine class from MHG through ENHG into NHG, measuring their token frequencies in different forms at different stages of their development. Token frequency is shown to have been the driving force behind the breakup of the class: in Groups 2, 3, and 4, the original weak forms that have been preserved and become the base of the rebuilt paradigm are, in most cases, the most frequent forms, while those that have been lost are correspondingly infrequent.

Advisor: Shannon, Thomas
Rauch, Irmengard
Essays on Macroeconomics and Monetary Policy

This dissertation improves our understanding of how the actions of the Federal Reserve and other central banks affect real activity in the economy. Chapters one and two show how secular change in the composition of investment spending in the United States has weakened the ability of conventional monetary policy tools (which alter the federal funds rate) to affect labor income and consumption. Specifically, Chapter one uses data on software developers collected from GitHub to show that firms are slow to adjust R&D activity and other so-called ''intangible investment'' in response to changes in interest rates because of congestion in onboarding the workers who produce it. Chapter two takes this result seriously as the explanation for the low observed responsiveness in the cross section for intangible investment as compared to tangible investment. Given the shift towards more and more intangible investment in the U.S. economy, this implies that investment spending overall is becoming less sensitive to changes in interest rates. Combined with two other secular changes documented in Chapter two---a rising import share in investment spending and a decline in the labor share of domestically produced investment---this implies that consumption and labor incomes for hand-to-mouth agents (and thus consumption and labor incomes overall) respond less to monetary policy shocks in general equilibrium. Finally, Chapter three uses novel historical data collected from the Bank of England to show that sterilized foreign exchange intervention (interventions in currency markets that hold policy rates fixed) can affect exchange rates.

Advisor: Romer, Christina
Nakamura, Emi