VictorJuiz/thesis huggingface dataset:
Search for Pair Production of a New b' Quark that Decays into a Z Boson and a Bottom Quark with the ATLAS Detector at the LHC

A search with the ATLAS detector for the pair production of a new b' quark in the Z boson plus b quark decay channel is reported. The pp collision data comprise 4.7 fb−1 of integrated luminosity at sqrt(s) = 7 TeV collected at the CERN Large Hadron Collider in 2011. This search complements recent searches for a b' decaying to a W boson and a top quark, and it is particularly important for new physics models containing vector-like quarks. From events containing both a Z boson reconstructed from electrons and a b tagged jet, any potential signal is enriched by selecting a subsample with large b' candidate pT. No evidence for a b' signal is found in this subsample; the invariant mass spectrum of the b' candidate agrees well with the Standard Model prediction. For the case of a b' that decays only to Z + b, masses mb' < 466 GeV are excluded at the 95% confidence level. Given the branching ratios of a vector-like singlet b' coupling only to the third Standard Model generation, masses mb' < 421 GeV are excluded.

Advisor: Shapiro, Marjorie D
The Electrodeposition of PbTe Nanowires for Thermoelectric Applications

Abstract/nThe Electrodeposition of PbTe Nanowires for Thermoelectric Applications/nby/nPeter Hillman/nDoctor of Philosophy in Chemistry/nUniversity of California, Berkeley/nProfessor Angelica Stacy, Chair/n/n/nThe electrodeposition of PbTe nanowires for thermoelectric applications is presented in this thesis. The Pb-Te electrochemical system was investigated to determine the optimal conditions for deposition. It was found that citric acid complexed tellurium in solution shifting its reduction potential cathodically. The shift in reduction potential led to the deposition of pure PbTe without any observable excess tellurium./nNanowires of PbTe were doped p-type and n-type through the addition of thallium and indium to the plating solution. Indium-doped nanowire arrays showed a linear relation between lattice parameter and atomic percent indium confirming successful incorporation. The lattice parameter trend in thallium-doped nanowire arrays was linear only after annealing. In the case of thallium doping, thallium tellurides were formed, which upon annealing formed a solid solution with PbTe./nThe results of the thallium doping study led to the investigation of the Tl-Te electrochemical system. Cyclic voltammagrams were used to determine the deposition mechanism of TlTe and Tl5Te3. Thin films and nanowire arrays of these compounds were deposited. This was the first study of the electrochemical Tl-Te system and the first report of the electrodeposition of TlTe and Tl5Te3./nThermoelectric measurements were conducted on thin films and nanowire arrays of PbTe. The Seebeck coefficient and resistivity of PbTe thin film were measured. Results from thin films were complicated by the Pt substrate on which PbTe was deposited. Subtracting the effects of the Pt layer suggested PbTe thin films could have a large zT, however further work is needed to confirm this result. Resistivity measurements on nanowire arrays were also conducted. Despite efforts to minimize the oxidation of PbTe nanowires, good electrical contacts could not be created. The resistivity of nanowire arrays were orders of magnitude higher than expected. As a result of their low conductivity, the thermoelectric efficiency of PbTe nanowires were negliglable./nNanotube arrays of conductive polyaniline were synthesized through the electrochemical deposition into porous anodic alumina. PbTe nanowires were deposited into these nanotubes to create a PbTe/polyaniline core-shell structure. PbTe/polyaniline hybrids should have a lower thermal conductivity than pure PbTe. Measurements of PbTe/polyaniline core-shell nanowires are still needed to confirm the predicted lower thermal conductivity.

Advisor: Stacy, Angelica M
After the Fact: Potential Collectivities in Israel/Palestine

This dissertation inquires into the question of collectivity in texts written in and about Israel/Palestine from the middle of the 20th century to the present day. In light of the current crisis in the configuration of both Israeli and Palestinian national collectivities, it explores the articulation of non-national collective formations in literary and cinematic texts. I read these texts not as sealed works that represent historically realized collectivities, but as creative projects whose very language and modalities speculatively constitute potential collectivities. Rejecting the progression of teleological history ruled by actualized facts, these projects compose a textual counter-history of Israel/Palestine. I therefore propose reading them outside of the national and state-centered paradigm that governs most political and cultural inquiries into Israel/Palestine, and suggest instead that they amount to an anti-colonial trajectory. The Hebrew and French texts discussed in the dissertation challenge their own fixed political positioning within the colonial matrix and offer a critique of European political dictates and artistic forms./nIn Chapter One, I discuss S. Yizhar's constant return to the events of the 1948 war and his refusal to move beyond it and narrate post-1948 sovereign, statist time; I consider the different literary procedures he employs throughout his work to potentially (re)constitute - after the establishment of the Israeli state - a pre-1948, non-national collective formation in Israel/Palestine. I then move, in Chapter Two, to follow the revolutionary collective enunciation fashioned by Jean-Luc Godard and the Dziga-Vertov collective, a group of politically-active filmmakers formed in 1968. I investigate the collectivity they attempted to develop together with Palestinian fighters in 1969-1970, the project's collapse after what is known as Black September, and finally its reflective afterlife in the 1976 film Ici et ailleurs. Chapter Three delves into the texts Jean Genet dedicated to the Palestinian struggle in the 1970s and -80s. I discuss how, in addressing his writing to a non-historical Palestinian collectivity which by then had already disappeared, Genet defies the boundaries of liberal politics of representation, and calls for a different notion of a gestural, "scripted" anti-colonial struggle. In Chapter Four I read contemporary Hebrew writer Haviva Pedaya's liturgical piyyut poetry, and ascertain how it may generate an oppositional history of Hebrew letters formulated from and towards Oriental collectivities, as a challenge to the modernist and secularist underpinnings of "modern Hebrew literature." Taken together, the projects I study recast Israel/Palestine as a political space in which both Palestinian and Jewish collectivities potentially emerge as anti-colonial, exilic, Eastern ones, formed in struggle and embedded in text.

Advisor: Kronfeld, Chana
A Ubiquitous Optical Microsystem Platform with Application to Optical Metrology and Chemical Sensing

This dissertation is concerned with the development of a novel, versatile optical sensor platform for optical metrology and chemical sensing. We demonstrate the feasibility of embedding optical components between bonded silicon wafers with receptor cavities and optical windows to create a self-contained sensor microsystem that can be used for in-situ measurement of hostile environments. Arrays of these sensors internal to a silicon wafer can enable optical sensing for in-situ, real-time mapping and process development for the semiconductor industry in the form of an instrumented substrate. Single-die versions of these optical sensor platforms can also enable point-of-care diagnostics, high throughput disease screening, bio-warfare agent detection, and environmental monitoring. Our first discussion will focus on a single-wavelength interferometry-based prototype sensor. Several applications are demonstrated using this single wavelength prototype: refractive index monitoring, SiO2 plasma etching, chemical mechanical polishing, photoresist cure and dissolution, copper etch end-point detection, and also nanopore wetting phenomena. Subsequent sections of this dissertation will describe efforts to improve the optical sensor platform to achieve multi-wavelength sensing function. We explore the use of an off-the-shelf commercial RGB sensor for colorimetric monitoring of copper and aluminum thin-film etchings. We then expand upon our prior work and concepts to realize a fully integrated, chip-sized microspectrometer with a photon engine based on a diffraction grating. The design, fabrication, and demonstration of a working prototype with dimensions < 1 mm thick using standard planar microfabrication techniques is described. Proof-of-concept demonstrations indicate the working principle of dispersion, although with a low spectral resolution of 120 nm. With working knowledge of the issues of the first prototype, we present an improved 5-channel microspectrometer with a spectral range 400-900 nm and demonstrate its ability for spectral identification with 3 different phosphor powder samples. Finally, we conclude with suggestions for future areas of research.

Advisor: Cheung, Nathan W
Stable Isotope Fractionations in Biogeochemical Reactive Transport

Characterizing the reactivity and fate of solutes in groundwater presents a formidable challenge in that these environments are inherently isolated from the observer. Samples are commonly limited to sediment cores and fluid collected from discrete well bores, while the measurements from these locations must be used to infer geochemical processes occurring across continuous, dynamic and heterogeneous systems. Stable isotope fractionations are an important tool in the quantitative analysis of reactive transport processes in porous media because they provide information coupled to, but distinct from solute concentrations. Examples of the combined analysis of solute concentrations and stable isotope fractionations abound in the literature, but almost entirely involve analytical models that decouple isotopic fractionation from the full extent of reactive pathways contributing to water-rock interaction in porous media flow./nIt is the purpose of this dissertation to apply analysis of stable isotopes to elucidate the processes of biogeochemical reactivity contributing to in situ bioreduction of uranium during electron donor augmentation in the Old Rifle aquifer in western Colorado. Bio-induced stabilization of heavy metals in subsurface systems involves a complex and concurrent series of dissimilatory reduction reactions, each with a unique metabolism and contaminant affinity. In such a complex system, application of simplified fractionation-reactivity relationships is shown to be inadequate to describe the behavior of multiple stable isotope systems. As a result, the methodology is developed to explicitly incorporate the isotopologues of these species into a multi-component reactive transport model of the system. The result is a means of mechanistically analyzing isotopic fractionation within an integrated framework encompassing the complete reactive network associated with electron-donor augmented bioreduction./nThe chapters herein are roughly divided into two sections. In the first half, sulfur and calcium isotopes are measured during field scale acetate amendments at Old Rifle. The results of these analyses demonstrate the utility of isotopic fractionation to track the development of terminal electron accepting processes and the formation of secondary mineral precipitates. However, these studies also demonstrate the limitations incurred by restriction to discrete well bores. In the second half, a flow-though column study is designed to overcome these limitations and test the extent to which individual isotopic fractionations are conserved during reactive transport under Old Rifle conditions. The results provide the first carbon budget during electron donor augmentation, and demonstrate that while the &delta34S fractionation induced by biogenic sulfate reduction is conservative, ion exchange effects dampen the &delta44Ca fractionation associated with carbonate precipitation.

Advisor: DePaolo, Donald J
Gangster Boogie: Los Angeles and the Rise of Gangsta Rap, 1965-1992

"Gangster Boogie" details the early development of hip-hop music in Los Angeles, a city that, in the 1980s, the international press labeled the "murder capital of the U.S." The rap music most associated with the region, coined "gangsta rap," has been regarded by scholars, cultural critics, and audiences alike as a tabloid distortion of East Coast hip-hop. The dissertation shows that this uniquely provocative genre of hip-hop was forged by Los Angeles area youth as a tool for challenging civic authorities, asserting regional pride, and exploiting the nation's growing fascination with the ghetto underworld. Those who fashioned themselves "gangsta rappers" harnessed what was markedly difficult about life in black Los Angeles from the early 1970s through the Reagan Era--rising unemployment, project living, crime, violence, drugs, gangs, and the ever-increasing problem of police harassment--to create what would become the benchmark for contemporary hip-hop music./nMy central argument is that this music, because of the social, political, and economic circumstances from which it emerged, became a vehicle for underclass empowerment during the Reagan Era. It concurrently presented civic authorities, community organizations, the press, and, eventually, the nation's top political leaders with a basis for the charge that hip-hop and violence were directly linked. The aim of this project is, primarily, to provide a lens for viewing events leading up to the 1992 Los Angeles Riots and, secondarily, to address the oft ignored connections between the ascendency of hip-hop and modern conservatism. I also intend for it to help bridge the gap between African-American cultural history and the historiography of the American West by reimagining the modern urban frontier, with all its temptations and contradictions, from the perspective of black inner-city youth.

Advisor: Litwack, Leon F.
Martin, Jr., Waldo E.
Political Subjectivity in Contemporary Arab Thought: The Political Theory of Abdullah Laroui, Hassan Hanafi, and Mohamed Abed al-Jabiri

This dissertation is an examination of the work of three twentieth century Arab thinkers and the significance of their thought to questions of political subjectivity and consciousness in political theory. The project analyzes the oeuvres of the Moroccan historian Abdullah Laroui, the Egyptian philosopher Hassan Hanafi, and the Moroccan philosopher Mohamed Abed al-Jabiri for the purpose of understanding how contemporary critiques of Arab-Islamic cultural heritage and ideology constitute a political theoretical tradition aimed at reforming the Arab political subject. Each thinker locates the consciousness of "the Arab self" at the heart of the troubled "Arab condition;" each conceives social and political progress as dependent upon the transformation of that consciousness. Thus, I argue that much of what usually passes as "cultural critique" in contemporary Arab thought should rather be considered as a critical examination of the formation of the Arab self carried out in the registers of cultural history, revisionist theology and ideology critique./nBy examining three quite different intellectual figures, I am able to show that the trend to identify the Arab self as the locus of Arab political problems, and to critique that self through an examination of the Arab-Islamic cultural tradition, is not limited to any single ideological current, but is practiced across contemporary Arab political thought. What varies among these thinkers is how they diagnose, characterize and attempt to redress this tradition. Whereas Laroui's critique culminates in a call for rupture with the tradition, Hanafi attempts its reconstruction and Jabiri offers a deconstruction aimed at sifting out and making use of its potentially progressive elements. Common to these various mobilizations of historical tradition is a modernist conception of history as necessarily progressive and as driven by a subject capable of shaping the future. Thus I argue that these thinkers and contemporary Arab thought more generally, inhabit an understanding that is counter-colonial but not yet postcolonial, one that is aware of the historicity of the Arab self and the profound influence of colonialism on its formation, yet is absent any critique of universalist and other conceits of Western modernity and democracy.

Advisor: Brown, Wendy
Organizational Identity and Interorganizational Alliances

This dissertation examines the relationship between organizational identity and the formation and performance implications of interorganizational alliances. The first study investigates the effect of an organization's identity on its initial alliance portfolio formation, addressing how becoming comprehensible through organizational identity is a fundamental step in order for a new organization to be accepted by the market. Through different categorizations, some new organizations will be more comprehensible and possess clearer identities in the market than others. I develop a theory of how this variation affects the search for alliance partners in terms of the speed of alliance formation and the diversity between the new organization and its partners. The second study investigates how organizational identity affects the impact of alliances on performance outcomes. Alliances that explore and experiment tend to affect organizational outcomes negatively, at least in the short term. Although exploration strategies facilitate learning and adaptation in the long run, they incur costs due to the nature of experimentation. I advance an alternative perspective that organizational identity plays a role in this alliance-performance link. Depending on the strength of an organization's identity in terms of how coherent and taken-for-granted its categorization or social grouping is, the effect on performance may be more or less negative. Overall, this research indicates that organizational identity matters both to an organization's initial alliance portfolio formation and to the impact of this alliance portfolio on performance outcomes. This work contributes to the literature streams of both organizational identity and alliances, and presents the first systematic investigation of the link between them.

Advisor: Ding, Waverly W.
Lincoln, James R.
Experimental and Simulation Study of Resistive Switches for Memory Applications

In recent years, resistive random access memory (RRAM) has gained significant attention as one of the promising candidates for next generation memory applications. This is due to its anticipated advantages versus Flash technology with respect to high density, low power and fast read and write speed. The main operation mechanism of these devices is a resistance change induced by filament formation through metal-cations or oxygen vacancies./nIn the first part of this work, a Kinetic Monte Carlo (KMC) simulator is built to study the filament formation process in an electrochemical metallization (ECM) RRAM. This simulator takes into account most important physical and chemical processes such as oxidation, reduction, metal crystallization, adsorption, desorption and ionic transportation. The characteristics of the forming voltage, forming time and switching speed are investigated. In addition, studies on filament overgrowth and on-state resistance distribution are presented. Further, filament topography, which strongly influences device properties, is studied under different device operation conditions. The simulator also predicts that depending on the strength of lateral electric field, the conductive filament can break at various locations during the RESET process. The simulation results are verified by experiments conducted on Ag/Ag2S/W and Cu/H2O/Cu systems./nIn the second part of this work, RRAM memory devices based on amorphous Yttria stabilized Zirconia (YSZ) are systematically studied. The effects of different top electrodes of Au, Cu, Ni, Al and Ti are investigated. And the characteristics and the mechanisms of Ti/YSZ and Cu/YSZ are studied in details. It is found that Ti/YSZ has much better endurance, retention and reliability than Cu/YSZ. The underlining physics driving this behavior is investigated. In addition, it is found that Ti/YSZ has very smooth transition in the RESET stage and the off state resistance exponentially increases with an increase of erase voltage. Based on those properties, a multi-level programming (MLP) cell is realized that shows good endurance. The underlying physics that makes the MLP possible for Ti/YSZ is investigated. Finally, it is shown that an incremental step pulse programming (ISPP) technique can significantly increase the device endurance and reliability. Furthermore, it can optimize the tradeoff between resistance programming window and device lifetime.

Advisor: Subramanian, Vivek
Intelligent Control of Robots with Mismatched Dynamics and Mismatched Sensing

Interest in industrial automation by robots has been continuously growing ever since the first industrial robot was installed in 1961. This creates an increasing demand for robot performance enhancement by means of intelligent control. Difficulties in meeting stringent performance requirements, however, arise by some inherent characteristics of the robots, which are: 1) mismatched dynamics (i.e., the control input and the system uncertainty/disturbance are in different channels), and 2) mismatched sensing (i.e., the system lacks of direct sensing of the desired output)./nA typical example of mismatched systems is an industrial robot with joint elasticity, the control objective of which is to obtain desired performances of the end-effector such as accurate positioning and tracking. This kind of robot can be characterized as a two-mass system with one mass being the motor side mass with control input and sensing and the other the load side/end-effector mass without control input or sensing, respectively. In this dissertation, several key technologies on intelligent control for this type of robot are introduced, including 1) handling mismatched sensing by sensor fusion, 2) handling mismatched dynamics by real-time control, and 3) handling mismatched dynamics by iterative learning control./nThis dissertation develops several sensor fusion algorithms to estimate both the load side and the end-effector states from limited sensing. The dynamic and kinematic models are utilized with consideration to problems such as fictitious noises and computation requirement. The well-developed sensor fusion schemes provide the essential desired information of the system for control purposes. With the mismatched sensing problem solved by sensor fusion, the control approaches to handle the mismatched dynamics are investigated in both the real-time domain and the iteration domain. Considering the nature of the mismatched system as a two-mass system, the real-time and iterative approaches are utilized in a hybrid two-stage manner to deal with the mismatched dynamics. The developed algorithms for sensor fusion and control provide not only the theoretical insights, but also the capability to address the real-world problems especially in industrial automation. Experimental studies on a single-joint research testbed and a commercial 6-DOF industrial robot manipulator have demonstrated the superior performance of the proposed algorithms.

Advisor: Tomizuka, Masayoshi