Dissertations / Theses on the topic 'Field'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 dissertations / theses for your research on the topic 'Field.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.
Rozario, Rebecca. "The Distribution of the Irreducibles in an Algebraic Number Field." Fogler Library, University of Maine, 2003. http://www.library.umaine.edu/theses/pdf/RozarioR2003.pdf.
Full textRakotoniaina, Tahina. "Explicit class field theory for rational function fields." Thesis, Link to the online version, 2008. http://hdl.handle.net/10019/1993.
Full textSmith, John D. "Scalar fields in quantum field theory and black holes." Thesis, University of Newcastle Upon Tyne, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.265489.
Full textLewis-Nash, Robert J. "Old Fields and New Fields: Ceramics and the Expanded Field of Sculpture." Oberlin College Honors Theses / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=oberlin150695125608167.
Full textEndres, Michael G. "Topics in lattice field theory /." Thesis, Connect to this title online; UW restricted, 2007. http://hdl.handle.net/1773/9713.
Full textGanic, Djenan, and dga@rovsing dk. "Far-field and near-field optical trapping." Swinburne University of Technology. Centre for Micro-Photonics, 2005. http://adt.lib.swin.edu.au./public/adt-VSWT20051130.135436.
Full textGanic, Djenan. "Far-field and near-field optical trapping." Australasian Digital Thesis Program, 2005. http://adt.lib.swin.edu.au/public/adt-VSWT20051130.135436.
Full textA thesis submitted for the degree of Doctor of Philosophy, Centre for Micro-Photonics, Faculty of Engineering and Industrial Sciences, 2005. Typescript. Includes bibliographical references (p. 164-177). Also available on cd-rom.
YANG, BING. "Source and field reconstruction with field splitting." Doctoral thesis, Politecnico di Torino, 2012. http://hdl.handle.net/11583/2503165.
Full textWang, Chun-yen. "Closed-time-path formalism for gauge field theory /." Digital version accessible at:, 2000. http://wwwlib.umi.com/cr/utexas/main.
Full textTarrús, Castellà Jaume. "Explicit Bound states and Resonance fields in Effective Field Theories." Doctoral thesis, Universitat de Barcelona, 2012. http://hdl.handle.net/10803/82144.
Full textEn el marc de teories efectives per a Cromodinàmica Quàntica a baixes energies, una situació interessant es presenta quan els graus de llibertat de baixes energies poden formar estats lligats, estats virtuals o ressonàncies pròximes al llindar. Com que aquest estats estan a prop del llindar afecten a les amplituds de dispersió, però tan mateix no poden ser descrites utilitzant teoria de pertorbacions, ja que les series polinòmiques finites en el moment no poden generar un pol en l’amplitud. Aquest pols es poden obtenir resumant certes classes de diagrames, per exemple usant tècniques d’unitarització, que no són consistents amb el comptatge de la teoria efectiva, o alternativament assumint un augment de l’importància de certs acoblaments. En aquest últim cas s’han de calcular les equacions del grup de renormalització per a tots els acoblaments per tal de determinar-ne el tamany correcte, el que dificulta mantenir la sèrie pertorbativa sota control. És una vella observació de Weinberg que la inclusió explícita d’estats lligats i ressonàncies com a graus de llibertat de la teoria efectiva millora la convergència de la teoria de pertorbacions. Es pot entendre fàcilment aquesta millora de la convergencia ja que les amplituds de dispersió tindran la estructura analítica correcta. Un dels temes principals d’aquesta tesi ha sigut explorar aquest fet dins d'un marc modern de teories efectives. El treball original d’aquesta tesi és als capítols 4 i 5. Al capítol 4 hem construït una teoria efectiva Quiral pel sistema nucleó–nucleó que conté camps dibariònics com a graus de llibertat fonamentals. Les longituds de dispersió grans en els canals 1S0 i 3S1 poden ser representades de forma natual gràcies a les petites masses residuals dels dibarions. Em calculat les amplituds de dispersió per aquesta teoria fins a NNLO per als canals 1S0 i 3S1-3D1, i em donat fòrmules d'extrapolació quiral per a les longituds de dispersió d'ona S fins a NLO. Al capítol 5 hem considerat la possiblitat de que l’espectre de QCD en el limit Quiral contingui un isosinglet escalar amb massa molt mes petita que l’escala hadroníca típica, i hem construït una teoria efectiva que l’inclou conjuntament amb els pseudo–bosons de Goldstone. Hem calculat la massa i la constant de decaïment del pion fins a NLO i hem ajustat els resultats a dades en el reticle. També hem estudiat les longituds de dispersió de les col•lisions pió-pió per a ona S en isospin I=0 i I=2 i les hem comprat amb dades al reticle.
Yang, Nan. "Molecules in Sculpted Fields: Magnetic Field Effects and Multipole Transitions." Thesis, Harvard University, 2012. http://dissertations.umi.com/gsas.harvard:10684.
Full textEngineering and Applied Sciences
Haines, Ross. "Simultaneous reconstruction of spatial frequency fields and field sample locations." Thesis, University of Oxford, 2016. https://ora.ox.ac.uk/objects/uuid:aa35073d-003b-4939-bf0e-8348243871b7.
Full textZhou, Sichao. "Complex Optical Fields Generation Using a Vectorial Optical Field Generator." University of Dayton / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1461689435.
Full textZhao, Xiang. "Aspects of conformal field theories and quantum fields in AdS." Electronic Thesis or Diss., Institut polytechnique de Paris, 2021. http://www.theses.fr/2021IPPAX103.
Full textThis thesis studies the structure and the space of conformal field theories (CFTs), and more generally various properties of conformal correlation functions. It extends into multiple directions, both perturbative and non-perturbative, local and non-local, with and without supersymmetry.The first aspect concerns the conformal correlation functions in d-dimensional spacetime and their relation to flat-space S-matrices in (d + 1)-dimensional spacetime. The connection is built up by considering a quantum field theory (QFT) in a fixed (d + 1)-dimensional Anti-de Sitter (AdS) background and sending the radius of the AdS curvature to infinity. That is, the central object to study is the flat-space limit of QFT in AdS. The analysis starts from taking the flat-space limit of the building blocks of Witten diagrams, namely the bulk-boundary and bulk-bulk propagators. This analysis leads to conjectural generic prescriptions to extracting flat-space physics from conformal correlators. Interestingly, the intuitional picture that a Witten diagram simply reduces to the corresponding Feynman diagram does not always hold and the origin of this discrepancy lies in the bulk-bulk propagators: they could have two different flat-space limits. One of the limits always exists and reduces to Feynman propagator, while the other, when present, diverges in the flat-space limit. This observation is tested by explicit examples, including four-point scalar contact, exchange and triangle Witten diagrams and the conjectures are expected to work whenever the scattering energy is large enough.The second aspect studies the classification problem of defect CFTs. The goal is to partially answer the question: given a bulk CFT and consistency conditions such as crossing symmetry and unitarity, what are the allowed conformal defects with a non-trivial coupling to the bulk? Analytic bootstrap techniques are applied to study a simplified version of this problem where in the bulk only a single free scalar field is considered. Analysis of various three-point functions among bulk and defect fields leads to the conclusion that almost all the n-point correlation functions of defect fields are completely fixed up to a potentially unfixed one-point function. This analysis also leads to an intermediate result in which it is proven that the n-point correlation functions of a conformal theory with a generalized free spectrum must be those of the generalized free field theory.The third aspect studies the interplay between analyticity in spin in CFTs and supersymmetry. Operator spectrum in a general unitary CFT is expected to be captured by a function analytic for spin L > 1, and the operators are organised into various Regge trajectories. The presence of supersymmetry in general extends the region of analyticity in spin. The 6d N = (2, 0) superconformal field theories (SCFTs) is considered as a concrete example, in which analyticity in spin is expected to hold down to L > -3. Detailed analysis of the four-point function of the the stress tensor supermultiplet uncovers an unexpected interplay between unprotected and protected multiplets: the stress tensor multiplet can be found on a long (unprotected) Regge trajectory when analytically continued to spin L = -2. In this study a general iterative bootstrap program is also established, which applies to all SCFTs that have a chiral algebra subsector
Bougourzi, A. Hamid. "Free field realization of extended conformal field theories." Thesis, McGill University, 1992. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=70279.
Full textKawai, S. "Boundary conformal field theory in free-field representation." Thesis, University of Oxford, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.249280.
Full textDarah, Alhashmi A. "Magnetic field generation within an ambient magnetic field." Thesis, University of Newcastle Upon Tyne, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.505835.
Full textDavis, Brian. "The Field." Digital Commons at Loyola Marymount University and Loyola Law School, 2017. https://digitalcommons.lmu.edu/etd/307.
Full textHelland, Madeline. "Field Guide." Scholarship @ Claremont, 2018. http://scholarship.claremont.edu/scripps_theses/1182.
Full textCedlind, Michael. "Field Recordings." Thesis, Konstfack, Institutionen för Konst (K), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:konstfack:diva-6780.
Full textCastilho, C. M. C. de. "Theory of field ionization in the field ion microscope." Thesis, University of Cambridge, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.373668.
Full textHuang, Tao. "Holographic techniques for antenna near-field/far-field measurements." Thesis, University of Sheffield, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.301549.
Full textCIORBA, LORENZO. "UAV-based Far-Field and Near-Field Antenna Measurements." Doctoral thesis, Politecnico di Torino, 2022. http://hdl.handle.net/11583/2972561.
Full textSimsir, Muazzez Fatma. "Conformal Vector Fields With Respect To The Sasaki Metric Tensor Field." Phd thesis, METU, 2005. http://etd.lib.metu.edu.tr/upload/12605857/index.pdf.
Full textMoreno, Almeida Javier. "Time evolution of inflaton fields in non-equilibrium quantum field theory." Thesis, University of Leeds, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.439566.
Full textSchritt, Dimitri. "Symmetries in quantum and classical field theories." Thesis, University of Canterbury. Physics and Astronomy, 2013. http://hdl.handle.net/10092/8032.
Full textSpanner, Michael. "Field-Free Alignment and Strong Field Control of Molecular Rotors." Thesis, University of Waterloo, 2004. http://hdl.handle.net/10012/1256.
Full textDaniel, Michael J. "Modular forms on a function field over a finite field." Connect to online resource, 2007. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3273712.
Full textKildén, Smith Martin. "Chaotic Field Exploration : Exploring systemic field dynamics in bilateral negotiations." Thesis, Linköpings universitet, Pedagogik och sociologi, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-114770.
Full text陶福臻 and Fook-tsun To. "Soliton solutions to gravitational field and Yang-Mills gauge field." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1993. http://hub.hku.hk/bib/B31233910.
Full textWatterson, P. A. "Force-free magnetic field evolution in the reversed-field pinch." Thesis, University of Cambridge, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.355048.
Full textКарнаушенко, В. П., and А. В. Бородин. "Field Programmable Counter Arrays Integration with Field Programmable Gates Arrays." Thesis, NURE, MC&FPGA, 2019. https://mcfpga.nure.ua/conf/2019-mcfpga/10-35598-mcfpga-2019-004.
Full textTo, Fook-tsun. "Soliton solutions to gravitational field and Yang-Mills gauge field /." [Hong Kong : University of Hong Kong], 1993. http://sunzi.lib.hku.hk/hkuto/record.jsp?B13671728.
Full textVaidya, Manushka. "Steering Electromagnetic Fields in MRI| Investigating Radiofrequency Field Interactions with Endogenous and External Dielectric Materials for Improved Coil Performance at High Field." Thesis, New York University, 2017. http://pqdtopen.proquest.com/#viewpdf?dispub=10261392.
Full textAlthough 1.5 and 3 Tesla (T) magnetic resonance (MR) systems remain the clinical standard, the number of 7 T MR systems has increased over the past decade because of the promise of higher signal-to-noise ratio (SNR), which can translate to images with higher resolution, improved image quality and faster acquisition times. However, there are a number of technical challenges that have prevented exploiting the full potential of ultra-high field (≥ 7 T) MR imaging (MRI), such as the inhomogeneous distribution of the radiofrequency (RF) electromagnetic field and specific energy absorption rate (SAR), which can compromise image quality and patient safety.
To better understand the origin of these issues, we first investigated the dependence of the spatial distribution of the magnetic field associated with a surface RF coil on the operating frequency and electrical properties of the sample. Our results demonstrated that the asymmetries between the transmit (B1+) and receive (B 1–) circularly polarized components of the magnetic field, which are in part responsible for RF inhomogeneity, depend on the electric conductivity of the sample. On the other hand, when sample conductivity is low, a high relative permittivity can result in an inhomogeneous RF field distribution, due to significant constructive and destructive interference patterns between forward and reflected propagating magnetic field within the sample.
We then investigated the use of high permittivity materials (HPMs) as a method to alter the field distribution and improve transmit and receive coil performance in MRI. We showed that HPM placed at a distance from an RF loop coil can passively shape the field within the sample. Our results showed improvement in transmit and receive sensitivity overlap, extension of coil field-of-view, and enhancement in transmit/receive efficiency. We demonstrated the utility of this concept by employing HPM to improve performance of an existing commercial head coil for the inferior regions of the brain, where the specific coil’s imaging efficiency was inherently poor. Results showed a gain in SNR, while the maximum local and head SAR values remained below the prescribed limits. We showed that increasing coil performance with HPM could improve detection of functional MR activation during a motor-based task for whole brain fMRI.
Finally, to gain an intuitive understanding of how HPM improves coil performance, we investigated how HPM separately affects signal and noise sensitivity to improve SNR. For this purpose, we employed a theoretical model based on dyadic Green’s functions to compare the characteristics of current patterns, i.e. the optimal spatial distribution of coil conductors, that would either maximize SNR (ideal current patterns), maximize signal reception (signal-only optimal current patterns), or minimize sample noise (dark mode current patterns). Our results demonstrated that the presence of a lossless HPM changed the relative balance of signal-only optimal and dark mode current patterns. For a given relative permittivity, increasing the thickness of the HPM altered the magnitude of the currents required to optimize signal sensitivity at the voxel of interest as well as decreased the net electric field in the sample, which is associated, via reciprocity, to the noise received from the sample. Our results also suggested that signal-only current patterns could be used to identify HPM configurations that lead to high SNR gain for RF coil arrays. We anticipate that physical insights from this work could be utilized to build the next generation of high performing RF coils integrated with HPM.
Webber, Matthew. "Stochastic neural field models of binocular rivalry waves." Thesis, University of Oxford, 2013. http://ora.ox.ac.uk/objects/uuid:c444a73e-20e3-454d-85ae-bbc8831fdf1f.
Full textNazarian, Bamshad. "Integrated Field Modeling." Doctoral thesis, Norwegian University of Science and Technology, Faculty of Engineering Science and Technology, 2003. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-84.
Full textThis research project studies the feasibility of developing and applying an integrated field simulator to simulate the production performance of an entire oil or gas field. It integrates the performance of the reservoir, the wells, the chokes, the gathering system, the surface processing facilities and, whenever applicable, gas and water injection systems.
The approach adopted for developing the integrated simulator is to couple existing commercial reservoir and process simulators using available linking technologies. The simulators are dynamically linked and customized into a single hybrid application that benefits from the concept of open software architecture. The integrated field simulator is linked to an optimization routine developed based on the genetic algorithm search strategies. This enables optimization of the system at field level, from the reservoir to the process. Modeling the wells and the gathering network is achieved by customizing the process simulator.
This study demonstrates that the integrated simulation improves currentcapabilities to simulate the performance of an entire field and optimize its design. This is achieved by evaluating design options including spread and layout of the wells and gathering system, processing alternatives, reservoir development schemes, and production strategies.
Effectiveness of the integrated simulator is demonstrated and tested through several field-level case studies that discuss and investigate technical problems relevant to offshore field development. The case studies cover topics such as process optimization, optimum tie-in of satellite wells into existing process facilities, optimal well location, and field layout assessment of a high pressure high temperature deepwater oil field.
Case study results confirm the viability of the total field simulator by demonstrating that the field performance simulation and optimal design were obtained in an automated process with reasonable computation time. No significant simplifying assumptions were required to solve the system and tedious manual data transfer between simulators, as conventionally practiced, was avoided.
Muenster, Korbinian. "String field theory." Diss., Ludwig-Maximilians-Universität München, 2013. http://nbn-resolving.de/urn:nbn:de:bvb:19-160964.
Full textHutcheson, Kenneth Andrew. "Geomagnetic field modelling." Thesis, University of Cambridge, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.385503.
Full textYfantouda, Renata Pires. "Field : smoking cessation." Thesis, City University London, 2007. http://openaccess.city.ac.uk/8555/.
Full text林君煌 and Kwan-wong Alan Lam. "The lost field." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2000. http://hub.hku.hk/bib/B3198521X.
Full textSmith, Joshua Reynolds. "Electric field imaging." Thesis, Massachusetts Institute of Technology, 1999. http://hdl.handle.net/1721.1/29144.
Full textIncludes bibliographical references (p. 213-216).
The physical user interface is an increasingly significant factor limiting the effectiveness of our interactions with and through technology. This thesis introduces Electric Field Imaging, a new physical channel and inference framework for machine perception of human action. Though electric field sensing is an important sensory modality for several species of fish, it has not been seriously explored as a channel for machine perception. Technological applications of field sensing, from the Theremin to the capacitive elevator button, have been limited to simple proximity detection tasks. This thesis presents a solution to the inverse problem of inferring geometrical information about the configuration and motion of the human body from electric field measurements. It also presents simple, inexpensive hardware and signal processing techniques for making the field measurements, and several new applications of electric field sensing. The signal processing contribution includes synchronous undersampling, a narrowband, phase sensitive detection technique that is well matched to the capabilities of contemporary microcontrollers. In hardware, the primary contributions are the School of Fish, a scalable network of microcontroller-based transceive electrodes, and the LazyFish, a small footprint integrated sensing board. Connecting n School of Fish electrodes results in an array capable of making heterodyne measurements of any or all n(n - 1) off-diagonal entries in the capacitance matrix. The LazyFish uses synchronous undersampling to provide up to 8 high signal-to-noise homodyne measurements in a very small package. The inverse electrostatics portion of the thesis presents a fast, general method for extracting geometrical information about the configuration and motion of the human body from field measurements. The method is based on the Sphere Expansion, a novel fast method for generating approximate solutions to the Laplace equation. Finally, the thesis describes a variety of applications of electric field sensing, many enabled by the small footprint of the LazyFish. To demonstrate the School of Fish hardware and the Sphere Expansion inversion method, the thesis presents 3 dimensional position and orientation tracking of two hands.
by Joshua Reynolds Smith.
Ph.D.
Gray, Michael D. "Convergent field elastography." Diss., Georgia Institute of Technology, 2015. http://hdl.handle.net/1853/53464.
Full textFazi, Filippo Maria. "Sound field reproduction." Thesis, University of Southampton, 2010. https://eprints.soton.ac.uk/158639/.
Full textBelote, Justin. "Cloud & Field." VCU Scholars Compass, 2015. http://scholarscompass.vcu.edu/etd/3753.
Full textLam, Kwan-wong Alan. "The lost field." Hong Kong : University of Hong Kong, 2000. http://sunzi.lib.hku.hk/hkuto/record.jsp?B25953047.
Full textPerlina, Anna. "Shaping the field." Doctoral thesis, Humboldt-Universität zu Berlin, Philosophische Fakultät I, 2016. http://dx.doi.org/10.18452/17672.
Full textThis dissertation represents a historical reconstruction of the development and transformation of German experimental psychology between the emergence of the first experimental laboratory in 1879 and its Gleichschaltung by the Nazi regime in the 1930s. It traces the evolution of the conceptual as well as the experimental framework of psychology over the course of these years following three generations of experimental research. Hereby, the work attempts to grasp how early experimental psychology negotiated its place between the humanities and the natural sciences. The project’s major focus lies in the period between 1922 and 1936, in which Kurt Lewin’s Berlin Experimental Program on Action and Emotions took place. The work specifically investigates the process of constitution of Lewin’s field theory, a system of concepts coined by Lewin in order to study psychological processes underlying human conduct. The dissertation shows how Lewin’s concepts emerged out of interdisciplinary sources, and how experimental practices in psychology triggered the emergence of new knowledge. Eventually, it is shown how the investigated historical case of Gestalt psychology in Berlin fits into and plays a decisive role in the long-term development of experimental psychology.
Sarala, J. (Jouni). "Low field NMR." Bachelor's thesis, University of Oulu, 2019. http://jultika.oulu.fi/Record/nbnfioulu-201907252707.
Full textDrummer, Emily. "Field of repose." Thesis, University of Iowa, 2018. https://ir.uiowa.edu/etd/6410.
Full textKilic, Delalcan. "The diffeomorphism field." Diss., University of Iowa, 2018. https://ir.uiowa.edu/etd/6156.
Full textMohamed, Adam. "Local Class Field Theory via Lubin-Tate Theory /." Thesis, Link to the online version, 2008. http://hdl.handle.net/10019/1936.
Full text