VictorJuiz/thesis huggingface dataset:
Nonlinear 3d frame element with multi-axial coupling under consideration of local effects

This study concerns the formulation and validation of a 3d frame element that accounts for the inelastic response under the interaction of axial, flexural, shear and torsional effects. The proposed finite element addresses the need for a general beam element capable of accurately simulating the global as well as the local response of slender structural elements./nThe new element accounts for the warping of arbitrary cross sections due to shear and torsion by introducing warping degrees of freedom at each section in order to accommodate higher order strain kinematics. The warping profile at a section uses the necessary number of Lagrange interpolation functions for the desired accuracy of local response. The warping distribution along the element axis is described by either Lagrange polynomials or spline interpolation functions. The number of interpolation parameters can be adjusted to control the accuracy of the local and global response./nThe 3d beam element formulation is derived from a mixed Hu-Washizu variational potential, with the inclusion of the warping displacements as independent variables. In the proposed formulation the section response is coupled through the interpolation of the stress resultants and the warping displacements along the element axis. Because the stress resultants satisfy the element equilibrium exactly with the use of suitable force interpolation functions, the element is free of shear-locking. Non-uniform warping is accommodated by the warping displacement distributions, so that the proposed element can represent the stresses arising from local warping constraints. The element is incorporated in a general purpose finite element analysis program with the consistent linearization of the governing equations for warping force equilibrium and for element compatibility resulting in a robust algorithm for the element state determination./nThe element is validated with several examples of linear and nonlinear material response of steel members. The linear elastic response is validated with analytical results, finite element models and some available experimental measurements. The inelastic response under monotonic and cyclic load conditions involves shear link specimens with wide flange and box section under high shear. The accuracy and computational efficiency of the proposed element is demonstrated by comparing the numerical results with available experimental measurements from eccentrically braced steel frames and with local response results from solid and shell finite element models./nThe study concludes with the investigation of the axial, flexural and torsion interaction under large displacements. The corotational formulation is derived from a general hypothesis that establishes the accuracy and scope of application of this method. Several numerical examples are used for the illustration of key nonlinear geometry aspects of slender elements under the interaction of axial, flexural and torsional effects.

Advisor: Filippou, Filip C
Moral Self-Esteem Enhancement: The Double-edge Sword in Social Judgments

In the current dissertation research, we resolved the different predictions and explored how moral self-esteem enhancement influences an individual's social judgments. By testing the effect of moral self-esteem enhancement in the current dissertation study, we first demonstrated that moral self-esteem was a dynamic, proactive motivational factor that could be changed by situational factors, such as by recalling people's previous moral actions (Study 1). Then we reconciled the different predictions about whether situational factors will make individuals render harsher moral judgments by linking the influence between the change of moral self-concept and affective reactions. When the nature of the social situation was clear, individuals tended to change their affective reaction to respond to the social situation in their judgments. In general, individuals with enhanced moral self-esteem intensified their affective reactions in their social judgments (Study 2). Finally, we emphasized the importance of the interaction between moral self-esteem enhancement and the nature of the social events. When the nature of the social events was ambiguous, individuals would rely on their self-concepts to make motivational attributions. In general, participants with moral self-esteem enhancement would seek for consistency between their self-concepts and their cognitive intention inference (Study 3 and Study 4). In the end, the theoretical contributions and the future research directions were discussed.

Advisor: Peng, Kaiping
Ab Initio Discovery of Regulatory Sequences and Characterization of Their Evolutionary Patterns

Background/nRecognizing regulatory sequences in genomes is a continuing challenge, despite a wealth of available genomic data and a growing number of experimentally validated examples./nMethodology/Principal Findings/nWe discuss here a simple approach to search for regulatory sequences based on the compositional similarity of genomic regions and known cis-regulatory sequences. This method, which is not limited to searching for predefined motifs, recovers sequences known to be under similar regulatory control. The words shared by the recovered sequences often correspond to known binding sites. Furthermore, we show that although local word profile clustering is predictive for the regulatory sequences involved in blastoderm segmentation, local dissimilarity is a more universal feature of known regulatory sequences in Drosophila./nConclusions/Significance/nOur method leverages sequence motifs within a known regulatory sequence to identify co-regulated sequences without explicitly defining binding sites. We also show that regulatory sequences can be distinguished from surrounding sequences by local sequence dissimilarity, a novel feature in identifying regulatory sequences across a genome.

Advisor: Eisen, Michael B
Contradictions and Vile Utterances: The Zoroastrian Critique of Judaism in the Shkand Gumanig Wizar

My dissertation examines the critique of Judaism in Chapters Thirteen and Fourteen of the Shkand Gumanig Wizar. The Shkand Gumanig Wizar is a ninth century CE Zoroastrian theological work that contains polemics against Islam, Christianity, and Manichaeism, as well as Judaism. The chapters on Judasim include citations of a Jewish sacred text referred to as the "First Scripture" and critiques of these citations for their contradictory and illogical portrayals of the divine. This dissertation comprises two parts. The first part consists of an introductory chapter, four interpretative essays, and a conclusion. The second part consists of a text and new English translation of Shkand Gumanig Wizar Chapters Thirteen and Fourteen./nMy first essay presents a new approach to the relation between the citations from the First Scripture in the Shkand Gumanig Wizar and Jewish literature. Previous scholars have tried to identify a single parallel text in the Hebrew Bible or rabbinic literature as the origin for each of citation. Borrowing approaches developed by scholars of the Qur'an and early Islamic literature, I argue that the Shkand Gumanig Wizar's critique draws on a more diverse and, likely, oral network of traditions about the biblical patriarchs and prophets./nMy second essay contains a close reading of three linked passages concerning angels in Shkand Gumanig Wizar Chapter Fourteen. I argue that the depiction of angels in these passages responds to a widespread Jewish belief in Metatron, an angelic co-regent whose power equals God's,. This essay analyzes the these angelic passages in light of the traces of this belief that can be found in the Babylonian Talmud, Jewish mystical literature, and other texts./nMy third essay concerns one of the longest citations in the critique of Judaism, a version of the story of the Garden of Eden from the first three chapters of the Book of Genesis. This essay demonstrates that this citation is one of a motif of connected and mutually illuminating garden passages found throughout the apologetic and polemical chapters of the Shkand Gumanig Wizar. I argue that gardens' prominence in the critique of Judaism, and the Shkand Gumanig Wizar as a whole, derives from gardens' symbolic role in Iranian culture./nMy final essay compares the critique of Judaism in the Shkand Gumanig Wizar to a Zoroastrian anti-Jewish text from another Middle Persian work, the Denkard. Whereas the earlier Denkard depicts Judaism mythically, relating the story of Judaism's creation by an evil demon, the Shkand Gumanig Wizar depicts Judaism textually, as citations from the First Scripture. I argue that the <Shkand Gumanig Wizar's presentation of Judaism as a text is an interpretative key for understanding the Zoroastrian work as a whole.

Advisor: Schwartz, Martin
An Experimental Based Investigation of Oxycombustion in an SI Engine

This work investigates oxycombustion in a spark-ignited (SI), piston engine. Oxycombustion is the process in which nearly pure oxygen and fuel are burned in a diluent of exhaust gas which is recirculated from the exhaust to the intake, referred to as exhaust gas recirculation (EGR). In typical air burning engines, EGR is used to reduce combustion temperatures, thereby reducing the formation of the pollutant nitric oxides (NOx). Conversely, the motivation for power generation using oxycombustion with EGR is the ease with which carbon dioxide (CO2) can be isolated in the exhaust for sequestration through a carbon capture and sequestration (CCS) process. At similar operating points the negative effect of EGR on the thermal efficiency of traditional air engines is magnified in oxycombustion due to the very high EGR levels. Therefore, it is the objective of this study to determine where the operating limits can be extended beyond the normal limits of air systems, regaining lost thermal efficiency./nTwo main EGR diluents are considered: dry EGR which is primarily CO2, and wet EGR, which includes both CO2 and water. Dry EGR has been found to have significantly higher knock resistance than air, allowing operation at higher compression ratios (CR) which can ultimately produce higher thermal efficiencies than air operation when combusting a low octane fuel. In fact, dry EGR produced higher thermal efficiencies when operating with low octane fuels (which have very poor knock resistance) than it did with high octane fuels (which have very high knock resistance). The primary reason for this anomaly was determined to be minor auto-ignition events, which significantly decrease combustion duration but do not produce significant knock, occurring with the low octane fuel. When operation is limited by engine configuration rather than knocking, as with methane, the performance of dry EGR is very low relative to air, roughly proportional to the decrease in theoretical thermal efficiency due to the decrease in the ratio of specific heats. In order to take advantage of the improved knock resistance it is necessary to operate in a region with a high enough CR and low enough oxygen concentration that minor auto-ignition events are common. Wet EGR produces similar trends as dry EGR, but cannot attain the high CRs which dry EGR operated at due to the elevated intake temperature required to prevent water condensation. Ultimately, despite the chemical and thermal advantages of water compared to CO2 in regards to laminar flame speeds, wet EGR with high water content is not a reasonable choice when operating in an IC engine. Despite its limitations in an IC engine, wet EGR has several advantages which should be carefully considered in applications where high initial temperatures are not propagated negatively.

Advisor: Dibble, Robert W
Poor Children's Social Development and Child Care Quality: Differential Associations Related to Race/Ethnicity of the Child Care Provider

The Growing Up in Poverty Project (GUP) examines the child care settings that women use as they move from welfare to work. In this study, I focused on two aspects of quality--structural features of quality and providers' personal attributes and their beliefs about child-rearing, their relationship to the social development of young children in these settings, and how the settings' care and quality vary with the children's and providers' race/ethnicity. The GUP sample included Anglo, African-American, and Latino providers and mothers with children 12-42 months old who used non-parental child care in child care centers, family day care homes (FDCH), or informal kith/kin settings./nSeveral instruments were used to measure structural level aspects of child care quality, the provider's affective and verbal responsiveness to children, the providers' responsiveness to children's language behaviors, and children's overall social development. Provider interviews explored their child care beliefs./nSalient findings include (a) in child care centers and family day care homes, Latina and African-American providers differed from Anglo providers in measures of structural level aspects of child care quality; (b) in child care centers, African-American providers displayed positive behaviors toward children more often than Anglo providers; (c) in FDCH/kith and kin settings (combined for most analysis), African-American providers were more likely than Anglo providers to request the child to speak; (d) child care providers reported a greater number of behavioral problems with male children, irrespective of their racial/ethnicity; (e) the longer the period during which the mother received welfare benefits, the lower the incidence of provider-reported child behavior problems, regardless of race/ ethnicity; (f) for African-American and Anglo providers, higher incomes were associated with fewer provider-reported child behavioral problems; and (g) the ethnic match between parent and childcare provider did not significantly influence provider-reported behavioral problem incidents in children./nThese findings support those of previous researchers in some areas: male children appear to be at greater risk for reported behavioral problems and children of less poor parents appear to display more positive child outcomes. The study contributed new data that further inform our knowledge in this area.

Advisor: Fuller, Bruce
Evaluating and Improving the ElarmS Earthquake Early Warning Algorithm

Earthquake Alarm Systems, or ElarmS, is a network-based earthquake early warning (EEW) system developed in California. This dissertation concerns the transition of ElarmS from research prototype to production-grade code. We test ElarmS' performance for large earthquakes with an extensive dataset of large events from Japan. Using the Japanese dataset and results, we develop a statistical error model for the magnitude, location, and ground motion prediction algorithms. We adapt ElarmS to run continuously throughout the state and analyze system latencies due to various seismic networks and instruments. We then rewrite ElarmS completely in newer, more efficient code, while redesigning the association and alert algorithms for improved performance. Finally, we apply an Artificial Neural Network (ANN) at the end of system processing, to detect and block false alerts. The ANN allows ElarmS to send earlier, faster alert messages, when fewer stations have contributed data to an event estimate. ElarmS now sends realtime alert messages to the California Integrated Seismic Network's ShakeAlert EEW system.

Advisor: Allen, Richard M
Evolutionary Differences between Two Lupines with Differing Mating Systems

The shift from outcrossing to selfing is one of the most common and evolutionarily significant transitions in flowering plants. Breeding system affects several evolutionary processes, which result in important differences between closely related selfing and outcrossing taxa. However, while the genetic and phenotypic differences between selfers and outcrossers have been documented often, the adaptive processes responsible for these changes are still not well understood./nIn this dissertation, I compare several populations of the outcrossing Lupinus nanus and the selfing L. bicolor, to investigate the genetic, selective, phenotypic, and adaptive consequences of mating system. I predicted that the selfing mating system of L. bicolor would result in low levels of genetic diversity and thus an inability to respond to selective pressures. The outcrossing nature L. nanus, on the other hand, should maintain sufficient intrapopulation genetic diversity to allow for natural selection to take place./nFirst, I used microsatellites to examine genetic diversity and population differentiation in both species to test the hypothesis that L. bicolor had less intrapopulation diversity and more interpopulation isolation than L. nanus. Second, I calculated the selective landscapes of both species and their ability to respond to selection. Third, I measured local adaptation in L. nanus and L. bicolor to answer the question: Do L. nanus or L. bicolor populations exhibit higher levels of local adaptation? Finally, I compared variance-covariance matrices to examine past evolutionary trajectories./nI found that L. bicolor has consistently lower intrapopulation genetic diversity and higher levels of isolation by distance than L. nanus. Additionally, L. nanus showed a consistent floral shift in the direction predicted by selection whereas L. bicolor did not, suggesting that L. bicolor is unable to respond to selective pressures due to its lack of genetic diversity. My measurements of local adaptation and home-site advantage were consistent with this finding, as all L. nanus populations showed evidence of home-site advantage, and three of the four populations were locally adapted, while L. bicolor showed neither home-site advantage nor local adaptation for any of my study populations. The variance-covariance matrix comparisons were less conclusive, showing moderate similarities among floral suites of traits for both L. nanus and L. bicolor./nWe conclude that, because L. bicolor is strongly selfing, it lacks the genetic diversity needed for selection to work on. Evolution in this species is likely dominated by neutral evolution, such as genetic drift. L. nanus, on the other hand, is not genetically depauperate and thus can respond to selective pressures. We also discuss the conservation and restoration implications of these findings.

Advisor: Simms, Ellen
Essays in Financial Liberalization and the Aggregate Economy

This dissertation consists of three essays on the effects of financial liberalization on the aggregate economy. In the first essay, I analyze empirically the effects of financial deregulation on wage inequality. To identify the causal effect of the reform, I exploit differences in external financial dependence and capital-skill complementarity across industries. I analyze two different episodes of deregulation: across countries within Europe and across states within the U.S. I provide evidence that, in both episodes, financial liberalization increases wage inequality disproportionally in industries with high financial needs and strong complementarity. I also find that the differential effect on relative wages is particularly strong in economies with rigid labor markets, while the effect on relative labor flows is stronger in economies with flexible labor markets./nIn the second essay, I conduct a quantitative analysis to calculate the effect of financial liberalization on aggregate inequality. I develop a simple two-sector general-equilibrium model with capital and labor market frictions. I calibrate the model in order to match the reduced form results documented in the first essay. According to a back-of-the envelope calculation, financial liberalization explains 20\% and 15\% of the increase in aggregate inequality in the U.K. and the U.S. during the 1980-2000 period, respectively. The simulation also shows that financial liberalization leads to an increase in the level of wages of both types of labor./n/nIn the third essay, co-authored with Sebastian Stumpner, we analyze empirically the effects of financial liberalization on total factor productivity (TFP) and capital misallocation. We use a large cross-country firm-level database and find that deregulation increases productivity disproportionally in industries with high financial needs and low asset tangibility. We decompose industry productivity into an average-productivity term and an allocation term, measured by the size-productivity covariance, and find that the industry TFP gains are primarily driven by a reduction in misallocation across firms. We also find that financial liberalization decreases the within-industry variance of the marginal product of capital and decreases the covariance between the marginal product of capital and TFP. Finally, we document that deregulation increases the market share of domestically-owned firms, which ex-ante are more financially constrained.

Advisor: Mian, Atif
Individual heterogeneity in life history processes: Estimation and applications of demographic models to stage-structured arthropod populations

Life history variation is a general feature of natural populations. Most studies assume that local processes occur identically across individuals, ignoring any genetic or phenotypic variation in life history traits. In part, this is because a realistic treatment of individual heterogeneity results in very complex population models. Fitting models with individual heterogeneity to real data is further complicated by random effects in groups of the data, observations set at specific intervals, and the non-independence of data following a cohort of individuals through time. In this dissertation, I assume that individuals differ in the duration they spend in each developmental stage and also in the amount of time they live. Stage durations and survival times follow probability distributions with parameters specific to populations and stages. Parameters of these distributions may also include random effects when considering a subset of sampled populations and covariates such as temperature. In the first chapter I formulate a model and likelihood for variable development, using the time-to-event model framework. In the second chapter I use this model to ask whether field populations of herbivorous arthropods (Tetranychus pacificus) form host-associations on different cultivars of the same host species. In the third chapter I incorporate variable development with variable survival and ongoing reproduction in a stage-structured population model. I explore the ability of the approximate Bayesian computation framework to fit such a complex model to data, evaluating posterior distributions and model performance.

Advisor: de Valpine, Perry