Dissertations / Theses: 'Squeegee'

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Dachner, Naomi. "An ethnographic study of homeless youth, the food experiences of squeegee kids." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape9/PQDD_0007/MQ46127.pdf.

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Hull, Angela Lynn. "Geochronology and thermochronology of Precambrian basement drill core samples in Nebraska and southeastern South Dakota." Kent State University / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=kent1385078311.

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Conradi, Michael C. "The social construction of squeegee kids as a law and order problem in neo-conservative Ontario, a content analysis of press coverage, 1995-1998." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ60674.pdf.

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Glowania, Micheal, Oliver Weichold, Markus Hojczyk, Gunnar Seide, and Thomas Gries. "Neue Beschichtungsverfahren für PVA-Zement-Composite in textilbewehrtem Beton." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2009. http://nbn-resolving.de/urn:nbn:de:bsz:14-ds-1244043027880-94266.

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Im Rahmen des Transferprojektes T01 „Textilbeschichtung mit hochviskosen Massen“ des Sonderforschungsbereiches 532 (SFB 532) wird die Realisierung und Bewertung eines integrierten Beschichtungskonzeptes zur nachhaltigen Verbesserung der Tragfähigkeit von textilbewehrten Betonbauteilen an der RWTH Aachen University untersucht. Dazu wird eine neue Auftragstechnik für hochviskose Beschichtungsmassen entwickelt, die eine vollständige Penetration von Multifilamentgarnen mit großen Garntitern und einer hohen Anzahl an Filamenten in textilen Gelegen erzielt. Des Weiteren werden aktive Beschichtungsmassen auf der Basis von Polyvinylalkohol-Zement-Compositen, die eine homogene Anbindung aller Einzelfilamente an die Zementmatrix ermöglichen, erforscht.

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Ward, Martin B. "Squeezed light in semiconductors." Thesis, University of Oxford, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.270175.

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Scott, Martin. "Atom : squeezed light interactions." Thesis, Queen's University Belfast, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.268311.

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Aggarwal, Nancy Ph D. Massachusetts Institute of Technology. "A room temperature optomechanical squeezer." Thesis, Massachusetts Institute of Technology, 2019. https://hdl.handle.net/1721.1/123354.

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This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Thesis: Ph. D., Massachusetts Institute of Technology, Department of Physics, 2019
Cataloged from student-submitted PDF version of thesis.
Includes bibliographical references (pages 294-306).
Decades of advancement in technologies pertaining to interferometric measurements have made it possible for us to make the first ever direct observation of gravitational waves (GWs). These GW emitted from violent events in the distant universe bring us crucial information about the nature of matter and gravity. In order for us to be able to detect GWs from even farther or weaker sources, we must further reduce the noise in our detectors. One of the noise sources that currently limits GW detectors comes from the fundamental nature of measurement itself. When a certain measurement reaches very high precision, the Heisenberg uncertainty principle comes into play. In GW detectors, this uncertainty manifests itself in the quantum nature of the light. Due to its quantum nature, light (or electromagnetic field) has an uncertain amplitude and phase.
Since the interferometric measurement is directly measuring the phase of light, this uncertainty poses a limit on the precision of GW measurements. Additionally, this measurement is also subject to quantum back-action, which arises due to the radiation pressure force fluctuations caused by the amplitude uncertainty (QRPN). In order to lower this quantum noise, GW detectors plan to use squeezed light injection. Squeezed light is a special quantum state of light which has lower uncertainty in a certain quadrature, at the expense of higher uncertainty in the orthogonal quadrature. In this thesis, I focus on using radiation-pressure-mediated optomechanical (OM) interaction to generate squeezed light. Creating squeezed states by using optomechanical interaction opens up possibilities for engineering truly wavelength-independent squeezed light sources that may also be more compact and robust than traditionally used non-linear crystals.
Additionally, this project inherently involves studying the OM interaction, which is the mechanism for back-action noise in GW detectors. Our basic setup is a Fabry-Perot cavity with a movable mirror. We start by understanding the physics of this system in the presence of realistic imperfections like losses and classical noise. This study furthers the previous work done on OM squeezing in an ideal Fabry-Perot cavity. We use this understanding of the system to optimize the experimental parameters to obtain the most possible squeezing in a broad audio-frequency band at room temperature. This optimization involves choosing the optical properties of the cavity, and the mechanical properties of the oscillator. We then present the experimental implementation of this design, and subsequent observation of QRPN as well as OM squeezing from the optimized design.
These observations are the first ever direct observation of a room temperature oscillator's motion being overwhelmed by vacuum fluctuations. More so, this is also the first time it has been shown in the low frequency band, which is relevant to GW detectors, but poses its own technical challenges, and hence has not been done before. Being in the back-action dominated regime along with optimized optical properties has also enabled us to observe OM squeezing in this system. That is the first direct observation of quantum noise suppression in a room temperature OM system. It is also the first direct evidence of quantum correlations in a audio frequency band, in a broadband at non-resonant frequencies.
by Nancy Aggarwal.
Ph. D.
Ph.D. Massachusetts Institute of Technology, Department of Physics

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Fuchs, Ingo. "Der aktienrechtliche Squeeze-out." Köln München Heymann, 2008. http://d-nb.info/993395112/04.

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Schucan, Gian-Mattia. "Generation of squeezed light in semiconductors." Thesis, University of Oxford, 1999. http://ora.ox.ac.uk/objects/uuid:417b1d31-8d25-42db-b707-32bd460b4183.

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We present experimental studies based on all three methods by which the generation of squeezed light in semiconductors has thus far been demonstrated experimentally: Fourwave mixing, multi-photon absorption and direct generation at the source. Four-wave mixing was used to generate femtosecond-pulsed quadrature squeezed light by cross-phase modulation in single-crystal hexagonal CdSe at wavelengths between 1.42 and 1.55 μm. We measured 0.4 dB squeezing (1.1 dB is inferred at the crystal) using 100 fs pulses. The wavelength and the intensity dependence, as well as variations in the local oscillator configuration were investigated. At higher intensities squeezing was shown to deteriorate owing to competing nonlinear processes. We also characterised the nonlinear optical properties of CdSe in this wavelengths range using an interferometric autocorrelator. In addition, we studied the feasibility of extending this technique to AlGaAs waveguides. The key problems are addressed and solutions are proposed. In a different experiment we used an AlGaAs waveguide to demonstrate for the first time photon-number squeezing by multi-photon absorption. By tuning the pump energy through the half bandgap energy we could effectively select two- or three-photon absorption as the dominant mechanism. Squeezing by these two mechanisms could be clearly distinguished and was found to be in good agreement with longstanding theoretical predictions. We also established the generality of the effect, by demonstrating the same mechanism in organic semiconductors, where it led to the first ever observation of squeezed light in an organic material. Finally, we present our measurements of photon-number squeezing in high-efficiency double heterojunction AlGaAs light-emitting diodes. We measured squeezing of up to 2.0 dB. In addition, we observed quantum noise correlations when several of these devices were connected in series.

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Zhou, Peng. "Interactions of atoms with squeezed light." Thesis, Queen's University Belfast, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.337055.

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Inoue, Shūichirō. "Squeezed state generation in semiconductor lasers /." Electronic version of summary, 1993. http://www.wul.waseda.ac.jp/gakui/gaiyo/1897.pdf.

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Huber, Verena. "Squeeze out : Rechtslage, Praxis, Bewertung /." Saarbrücken : VDM, Müller, 2005. http://deposit.ddb.de/cgi-bin/dokserv?id=2705089&prov=M&dok_var=1&dok_ext=htm.

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Weatherall, Nicholas Owen. "Quantum Stochastic Calculus for Thermal (squeezed)Noise." Thesis, Lancaster University, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.518151.

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Lyubomirsky, Ilya. "Quantum reality and squeezed states of light." Thesis, Massachusetts Institute of Technology, 1994. http://hdl.handle.net/1721.1/36431.

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Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1994.
Includes bibliographical references (leaves 67-71).
by Ilya Lyubomirsky.
M.S.

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Oelker, Eric Glenn. "Squeezed states for advanced gravitational wave detectors." Thesis, Massachusetts Institute of Technology, 2016. http://hdl.handle.net/1721.1/107044.

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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Physics, 2016.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 219-229).
Quantum vacuum fluctuations impose strict limits on precision displacement measurements, those of interferometric gravitational-wave detectors among them. Introducing squeezed states into an interferometer's readout port can improve the sensitivity of the instrument, leading to richer astrophysical observations. In recent years, this technique has been used to improve the sensitivity of the GEO600 [1011 and the Initial LIGO detector at Hanford, WA [102]. Squeezed states could be employed in advanced gravitational-wave detectors, such as Advanced LIGO, to further push the limits of the observable gravitational wave universe. To maximize the benefit from squeezing, environmentally induced disturbances such as back scattering and angular jitter need to be mitigated. Also, optomechanical interactions dictate that the quadrature of the squeezed vacuum state must rotate by 900 at around 50 Hz in order to achieve a broadband sensitivity improvement for Advanced LIGO. In this thesis we describe a series of experiments that lead to a ultra-high vacuum (UHV) compatible, low phase noise, and frequency-dependent squeezed vacuum source required for Advanced LIGO and future gravitational-wave detectors. In order to develop the required technology, two proof-of-principal experiments were conducted. In the first experiment, we built a UHV compatible squeezed vacuum source and homodyne readout and operated them in UHV conditions. We also commissioned a control scheme that achieved a record low 1.30-7 mrad of phase noise. This is a nearly tenfold improvement over previously reported measurements with audio-band squeezed vacuum sources. In the second experiment we used a 2-m-long, high-finesse optical resonator to produce frequency-dependent squeezed quadrature rotation around 1.2kHz. This demonstration of audio-band frequency-dependent squeezing uses technology and methods that are scalable to the required rotation frequency for Advance LIGO, firmly establishing the viability of this technique for application in current and future gravitational-wave detectors. We conclude with a discussion of the implications of these results for squeezing enhancement in Advanced LIGO and beyond.
by Eric Oelker.
Ph. D.

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Young, Joseph Y. J. 1968. "Squeeze-film damping for MEMS structures." Thesis, Massachusetts Institute of Technology, 1998. http://hdl.handle.net/1721.1/34334.

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Ahmad, Rosli. "Optimisation of the squeeze forming process." Thesis, Swansea University, 2006. https://cronfa.swan.ac.uk/Record/cronfa42636.

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This thesis presents the optimisation of the squeeze forming process, considering both the thermal and mechanical aspects. The Finite Element Method has been used to simulate the process and a Genetic Algorithm was used as an optimisation tool. The thermal optimisation has been applied to the squeeze forming process to achieve near simultaneous solidification in the cast part. The positions of the coolant channels were considered as design variables in order to achieve such an objective. The formulation of the objective functions involved two points and also considered the whole domain. The validation aspects of the optimisation of the casting processes for 2D and axi-symmetric problems were presented. The influence of the interfacial heat transfer coefficient related to optimisation of the process was explored. For the multi-objective optimisation problem, the objective was to achieve near simultaneous solidification in the cast part and also near uniform von Mises stress distribution in the die for the first and also tenth cycles. This is because it has been found that the process starts to reach cyclic stabilisation after the tenth cycle. The comparison between the design obtained from the practical solution derived from the optimisation process and also the design which has been applied in industry was also discussed. The Design Sensitivity Analysis and Design Element Concept have been applied to the squeeze forming process. For parameter sensitivity analysis, the Youngs Modulus was considered as a design variable. A few design element subdivisions have been employed to explore its application to the process. For shape sensitivities involving the coolant channels, the parameterisation was required in order to consider the coolant channel as an entity. The extent to which the tendency to move the coolant channel either in the X or Y-direction with respect to the particular von Mises stress constraint in the die was also discussed.

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Yates, Nicola Marie. "The squeeze flow rheometry of foods." Thesis, University of Birmingham, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.403090.

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Food pastes and suspensions are complex materials which are difficult to characterise in conventional rotational rheometry due to their complex microstructure and their usual tendency to slip at the wall. Squeeze flow, in which material flows between two circular plates as they are brought together, has traditionally been used as a way of overcoming these problems. Two squeeze flow rheometers were set up incorporating two novel pressuresensing devices, a strip sensor and a grid sensor. The strip sensor which measures the pressure distribution in the material along a radius, was found to be too sensitive to test fluids. The grid sensor which measures the whole two-dimensional pressure distribution in the material, was more robust and was validat~d using Newtonian silicone oils. Excellent agreement was found between the pressure sensor data and the well-known Stefan's theory, over the range of dimensionless times 0.4 to 0.8. On extension to non-Newtonian fluids, reasonable agreement was found between the well-known Scott's theory and the pressure data for a model pseudoplastic fluid, over an equivalent range of dimensionless times. The results for a paste material, however, did not agree well with Scott's theory. The flow regime in squeeze flow is different to that found in the simple shear flow of rotational rheometers. In squeeze flow the flow pattern changes from elongational to shear flow as the experiment progresses, which has two consequences: (i) it is unlikely that a single rheological equation could describe the flow over the whole experiment and (ii) the different flow regimes mean that comparison with rheological parameters obtained from conventional rheometry is unlikely to be successful.

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Daly, Elizabeth Marion. "Generation, measurement, and application of pulsed squeezed light." Thesis, University of Strathclyde, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.367066.

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Zhang, Mi. "Study of Spatial Structure of Squeezed Vacuum Field." W&M ScholarWorks, 2016. https://scholarworks.wm.edu/etd/1499450043.

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Squeezed states of light, with field fluctuations smaller than the coherent state fluctuations (or shot noise), are used for improving accuracy of quantum-noise limited measurements, like the detection of gravitational waves. They are also essential resources for quantum information transfer protocols. We studied a squeezed vacuum field generated in hot Rb vapor via the polarization self-rotation effect. We studied the mode structure of the squeezed field by spatially-masking the laser beam after its interaction with the Rb atomic vapor. From analysis of the data we developed a multi-mode theory to simulate the mode composition of the squeezed vacuum field. Our experiments showed that the amount of observed squeezing may be limited by the complex mode structure due to the excitement of higher order spatial modes during the nonlinear atom-light interaction. We demonstrated that optimization of the spatial profile of the beam led to higher detected squeezing. Our studies are useful for enhancing precision metrology and quantum memory applications.

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Dwyer, Sheila E. (Sheila Elizabeth). "Quantum noise reduction using squeezed states in LIGO." Thesis, Massachusetts Institute of Technology, 2013. http://hdl.handle.net/1721.1/79427.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Physics, 2013.
This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Title as it appears in MIT Commencement Exercises program, June 2013: Sensitivity improvement of a LIGO gravitational Wayne detector through squeezed state injection. Cataloged from student-submitted PDF version of thesis.
Includes bibliographical references (p. 217-223).
Direct detection of gravitational waves will require earth based detectors to measure strains of the order 10-21, at frequencies of 100 Hz, a sensitivity that has been accomplished with the initial generation of LIGO interferometric gravitational wave detectors. A new generation of detectors currently under construction is designed improve on the sensitivity of the initial detectors by about a factor of 10. The quantum nature of light will limit the sensitivity of these Advanced LIGO interferometers at most frequencies; new approaches to reducing the quantum noise will be needed to improve the sensitivity further. This quantum noise originates from the vacuum fluctuations that enter the unused port of the interferometer and interfere with the laser light. Vacuum fluctuations have the minimum noise allowed by Heisenberg's uncertainty principle, [Delta]X1 [Delta]X2 >/=1, where the two quadratures X1 and X2 are non-commuting observables responsible for the two forms of quantum noise, shot noise and radiation pressure noise. By replacing the vacuum fluctuations entering the interferometer with squeezed states, which have lower noise in one quadrature than the vacuum state, we have reduced the shot noise of a LIGO interferometer. The sensitivity to gravitational waves measured during this experiment represents the best sensitivity achieved to date at frequencies above 200 Hz, and possibly the first time that squeezing has been measured in an interferometer at frequencies below 700 Hz. The possibility that injection of squeezed states could introduce environmental noise couplings that would degrade the crucial but fragile low frequency sensitivity of a LIGO interferometer has been a major concern in planning to implement squeezing as part of baseline interferometer operations. These results demonstrate that squeezing is compatible with the low frequency sensitivity of a full scale gravitational wave interferometer. We also investigated the limits to the level of squeezing observed, including optical losses and fluctuations of the squeezing angle. The lessons learned should allow for responsible planning to implement squeezing in Advanced LIGO, either as an alternative to high power operation or an early upgrade to improve the sensitivity. This thesis is available at DSpace@MIT and has LIGO document number P1300006.
by Sheila E Dwyer.
Ph.D.

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Nee, Phillip Tsefung. "Generation of squeezed light via second harmonic generation." Thesis, Massachusetts Institute of Technology, 1994. http://hdl.handle.net/1721.1/34050.

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Hua, Tao. "Study on marriage squeeze in Hong Kong /." View abstract or full-text, 2006. http://library.ust.hk/cgi/db/thesis.pl?SOSC%202006%20HUA.

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Han, Yingke. "Nonlinear fluid forces in cylindrical squeeze films." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp02/NQ29466.pdf.

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Akaiwa, Michiro. "The electrorheological effect in static squeeze-flow." Thesis, University of Liverpool, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.367103.

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Rigby, Simon Geoffrey. "The electrorheological effect in oscillatory squeeze-flow." Thesis, University of Liverpool, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.284149.

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El-Shafei, Aly. "Dynamics of rotors incorporating squeeze film dampers." Thesis, Massachusetts Institute of Technology, 1988. http://hdl.handle.net/1721.1/87804.

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Kituri, Peter Maganga. "Margin squeeze in the South African context." Master's thesis, University of Cape Town, 2014. http://hdl.handle.net/11427/12919.

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Includes bibliographical references.
Following the introduction of the margin squeeze cause of action into South African competition law jurisprudence, the question arises whether the Senwes decisions, have definitively clarified the criteria against which future margin squeeze abuse cases will be dealt with and whether these criteria have evolved into a standalone cause of action. This dissertation will demonstrate the absurdity of the Constitutional Court decision, to delete all references to margin squeeze in the decision of the Competition Tribunal which it upheld while retaining the underlying criteria against which future margins queeze cases will be adjudicated. This dissertation will additionally demonstrate that the Senwes cases, in particular the Tribunal decision read with the Constitutional Court decision, have on the one hand only marginally delineated and elaborated on the elements necessary to establish a margin squeeze abuse, but have on the other hand established margin squeeze as a standalone cause of action in terms of which offending firms can be prosecuted in South African competition jurisprudence.

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Martin, Ciurana Ferran. "Coherent sensing of magnetic waveforms with spin-squeezed atoms." Doctoral thesis, Universitat Politècnica de Catalunya, 2017. http://hdl.handle.net/10803/461830.

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Optical magnetometers use magnetically-sensitive atomic ensembles and optical read-out to detect the amplitude of magnetic fields. They have become the most sensitive instruments for measuring low-frequency magnetic fields surpassing competing technologies like superconducting quantum interface devices (SQUIDs), and find applications in a variety of fields ranging from medicine, biology and geophysics, as well as tests of fundamental physics. However, their fundamental sensitivity is bounded by quantum mechanical behavior of the atoms, which gives rise to the standard quantum limit (SQL). As many instruments are approaching this fundamental limit, it becomes necessary to explore ways to overcome the SQL. Quantum metrology studies strategies to increase the sensitivity beyond the SQL by means of quantum engineering the atomic states. In this thesis, we investigate the quantum enhanced detection of time varying radio-frequency magnetic fields using a cold atomic ensemble of 87Rb atoms held in an optical dipole trap. We first theoretically develop a new measurement technique based on stroboscopic back-action evading measurements that takes advantage of the atomic coherence. This measurement scheme is suitable for the detection of arbitrarily-chosen components of radio-frequency waveforms and includes radio-frequency magnetometry as a special case. Experimentally, we demonstrate the capabilities of this technique using a linearly chirped waveform as a test case. As a first experiment, we demonstrate the selective response of the method in the coherently accumulated signal by the atoms. For this, we dispersively probe the atoms via Faraday rotation and non-destructively measure the induced magnetization. In the last part of the thesis we demonstrate quantum enhanced magnetic field detection. In a measure-evolve-measure (MEM) sequence, a first stroboscopic quantum non-demolition (QND) measurement produces a state with reduced projection noise, followed by a period of free evolution where the atoms accumulate signal. A second QND measurement detects the change relative to the first measurement. We demonstrate entanglement-enhanced sensing of sinusoidal and linearly chirped waveforms, with metrologically-relevant noise reduction of _2m =0.84(8) and _2m =0.80(3), respectively. We achieve volume-adjusted sensitivity of _B p V _ 3.96 fT p cm3/Hz, comparable to the best radio-frequency magnetometers.
Els magnetòmetres òptics utilitzen conjunts d’àtoms sensibles magnèticament i lectura òptica per detectar l’amplitud de camps magnètics. S’han convertit en els instruments més sensibles per mesurar camps magnètics de baixa freqüència, superant tecnologies rivals com els dispositius superconductors d’interfície quàntica (SQUID), alhora que troben aplicacions en camps tan diversos com la medicina, la biologia, la geofísica, fins a proves de física fonamental. No obstant això, la seva sensibilitat està fonamental limitada pel comportament quàntic dels àtoms que dóna lloc al límit quàntic estàndard (SQL). Donat que molts instruments s’aproximen a aquest límit fonamental, es imprescindible explorar maneres de superar-ho. La metrologia quàntica estudia estratègies per augmentar la sensibilitat més enllà del SQL mitjançant enginys quàntics en l’estat dels àtoms. En aquesta tesi investiguem la detecció de camps magnètics de freqüència de ràdio amb un conjunt d’atòms freds de 87Rb mantinguts en una trampa de dipol òptic. En primer lloc, desenvolupem teòricament una nova tècnica de mesura basada en mesures estroboscòpiques que eviten la contra-acció de la mesura alhora que permet aprofitar la coherència atòmica. Aquest esquema de mesura és compatible amb la detecció de components elegits arbitràriament de formes d’ona de freqüència de ràdio i inclou la magnetometria de radiofreqüència com a cas especial. Demostrem experimentalment les capacitats d’aquesta tècnica utilitzant una forma d’ona de prova amb canvi de freqüència lineal. Al primer experiment, demostrem la resposta selectiva del mètode en la senyal coherent acumulada pels àtoms. Per aconseguir-ho, provem de forma dispersiva els àtoms amb la sonda Faraday i mesurem no destructivament oscil·lació de Rabi de la població atòmica entre els subnivells magnètics dels nivells hiperfins de l’àtom. A la darrera part de la tesi, demostrem la detecció de l’amplitud de camps magnètics amb precisió millorada gràcies a efectes quàntics. En una seqüència de mesura-evolució-mesura (MEM), una primera mesura quàntica, estroboscòpica i no destructiva (QND) produeix un estat amb soroll de projecció atòmic reduït. El segueix un període d’evolució lliure on els àtoms s’acumulen senyal. Una segona mesura QND detecta el canvi relatiu a la primera mesura. Demostrem detecció millorada per entrellaçament quàntic per a formes d’ona sinusoïdals i amb canvi de freqüència lineal, amb reduccions de soroll metrològicament rellevants ξ2m =0.84(8) i ξ2m =0.80(3), respectivament. Aconseguim una sensibilitat ajustada pel volum B p V 3.96 fT p cm3/Hz, comparable als millors magnetòmetres operant a freqüència de ràdio.

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Lam, Ping Koy, and Ping Lam@anu edu au. "Applications of Quantum Electro-Optic Control and Squeezed Light." The Australian National University. Faculty of Science, 1999. http://thesis.anu.edu.au./public/adt-ANU20030611.170800.

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In this thesis, we report the observations of optical squeezing from second harmonic generation (SHG), optical parametric oscillation (OPO) and optical parametric amplification (OPA). Demonstrations and proposals of applications involving the squeezed light and electro-optic control loops are presented. ¶ In our SHG setup, we report the observation of 2.1 dB of intensity squeezing on the second harmonic (SH) output. Investigations into the system show that the squeezing performance of a SHG system is critically affected by the pump noise and a modular theory of noise propagation is developed to describe and quantify this effect. Our experimental data has also shown that in a low-loss SHG system, intra-cavity nondegenerate OPO modes can simultaneously occur. This competition of nonlinear processes leads to the optical clamping of the SH output power and in general can degrade the SH squeezing. We model this competition and show that it imposes a limit to the observable SH squeezing. Proposals for minimizing the effect of competition are presented. ¶ In our OPO setup, we report the observation of 7.1 dB of vacuum squeezing and more than 4 dB of intensity squeezing when the OPO is operating as a parametric amplifier. We present the design criteria and discuss the limits to the observable squeezing from the OPO.We attribute the large amount of squeezing obtained in our experiment to the high escape efficiency of the OPO. The effect of phase jitter on the squeezing of the vacuum state is modeled. ¶ The quantum noise performance of an electro-optic feedforward control loop is investigated. With classical coherent inputs, we demonstrate that vacuum fluctuations introduced at the beam splitter of the control loop can be completely cancelled by an optimum amount of positive feedforward. The cancellation of vacuum fluctuations leads to the possibility of noiseless signal amplification with the feedforward loop. Comparison shows that the feedforward amplifier is superior or at least comparable in performance with other noiseless amplification schemes. When combined with an injection-locked non-planar ring Nd:YAG laser, we demonstrate that signal and power amplifications can both be noiseless and independently variable. ¶ Using squeezed inputs to the feedforward control loop, we demonstrate that information carrying squeezed states can be made robust to large downstream transmission losses via a noiseless signal amplification. We show that the combination of a squeezed vacuum meter input and a feedforward loop is a quantum nondemolition (QND) device, with the feedforward loop providing an additional improvement on the transfer of signal. In general, the use of a squeezed vacuum meter input and an electro-optic feedforward loop can provide pre- and post- enhancements to many existing QND schemes. ¶ Finally, we proposed that the quantum teleportation of a continuous-wave optical state can be achieved using a pair of phase and amplitude electro-optic feedforward loops with two orthogonal quadrature squeezed inputs. The signal transfer and quantum correlation of the teleported optical state are analysed. We show that a two dimensional diagram, similar to the QND figures of merits, can be used to quantify the performance of a teleporter.

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31

Funk, Andrew Christopher. "Cryptography using two-mode quantum mechanically squeezed optical pulses /." view abstract or download file of text, 2004. http://wwwlib.umi.com/cr/uoregon/fullcit?p3120623.

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Thesis (Ph. D.)--University of Oregon, 2004.
Typescript. Includes vita and abstract. Includes bibliographical references (leaves 204-209). Also available for download via the World Wide Web; free to University of Oregon users.

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Tison, Christopher C. "Central Moments of Squeezed States| A Coincidence Statistics Analogue." Thesis, Florida Atlantic University, 2018. http://pqdtopen.proquest.com/#viewpdf?dispub=10748521.

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As a subset of quantum optics, single photons are one of the competing physical resources for quantum information processing. When used as carriers of quantum information, they have no equal. For the processing of quantum information, single photons have proven difficult to scale beyond the order of ~10 photons. The lack of single-photon-level interaction has led to creative approaches which rely on post-selection to filter the possible measured outcomes to those which appear as though interaction occurred. This approach of post-selection leans heavily on the ability to not only generate but also detect scores of single photons simultaneously and with near perfect efficiency. Our work relaxes the emphasis which has been placed on single photons for quantum information processing to that of states with, in principle, an arbitrary number of photons. Central moment expectations on two-mode squeezed states are shown to exhibit post-selection behavior which reflects the single-photon counterpart. These measures are proven to be robust to loss and return entangled state statistics on average. With naive estimation of the central moment, states with ~20 modes are within reach with current technology, closing the gap between quantum states which can and cannot be classically simulated.

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Haas, Steven Frederick 1955. "Effects of a squeezed vacuum on absorptive optical bistability." Thesis, The University of Arizona, 1988. http://hdl.handle.net/10150/276900.

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The effects of a squeezed vacuum on absorptive optical bistability (AOB) are calculated using the different relaxation rate approximation for in-quadrature and in-phase components of a two-level system developed by Gardiner. An expression for the complex absorption coefficient is developed, and the result applied to the AOB equation for the unidirectional ring cavity. We find a significant degradation of bistability for values of the in-quadrature decay constant less than or equal to approximately.5 of the in-phase decay constant. Effects of detuning and relative phase of the pump field to the squeezed vacuum field are also examined.

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Greaves, Matthew. "Acoustic liners of jet engines." Thesis, Loughborough University, 2001. https://dspace.lboro.ac.uk/2134/33817.

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Acoustic liners employing the Helmholtz resonator concept are commonly used in the intake duct of modern jet engines to reduce radiated noise. In response to reports of core failures, the possibility of acoustic loading as the source of these liner failures is investigated. Experimental data are used as input to a model for non-rigid cavity walls and the induced stresses analysed. An alternative, more robust, liner design utilizing viscous damping is proposed, and an analytical model developed and numerically validated against published data. A study of the key parameters leads to an improved configuration, the attenuating properties of which are compared to a typical liner.

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Jakobs, Angela. "Die Rechte des Minderheitsaktionärs beim aktienrechtlichen Squeeze-out /." Hamburg : Kovač, 2007. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=016487966&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.

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Amberger, Claus-Peter. "Die Missbrauchskontrolle im Rahmen des aktienrechtlichen Squeeze-out." Berlin BWV, Berliner Wiss.-Verl, 2006. http://deposit.d-nb.de/cgi-bin/dokserv?id=2992891&prov=M&dok_var=1&dok_ext=htm.

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Warchol, Joanna. "Squeeze-Out in Deutschland, Polen und übrigen Europa /." Baden-Baden : Nomos, 2008. http://d-nb.info/989458377/04.

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Manson-Whitton, Chris. "Squeeze casting of a conventionally wrought aluminium alloy." Thesis, University of Oxford, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.403577.

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Britnell, David John. "Pressure assisted segregation in squeeze cast aluminium alloys." Thesis, University of Warwick, 1996. http://wrap.warwick.ac.uk/59214/.

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A study has been conducted into Pressure Assisted Macrosegregation during the squeeze casting of an aluminium alloy, LM25, and an aluminium based silicon carbide particulate metal matrix composite. The squeeze casting process is particularly prone to this type of segregation which results in large areas of solute rich material in the final casting. The fundamental causes of the segregation have, until now, not been fully understood. This has restricted the use of squeeze casting as it was believed that the cause was a fundamental manufacturing weakness. An existing squeeze casting facility at Warwick was used to produce cast samples for study. The facility produces simple tensile test bars. Inserts for the die were designed to specifically produce the segregation within the castings. Thermocouples were threaded through the die wall and placed within the casting to enable the recording of the thermal history during solidification. Samples were taken from the castings, mounted, ground and polished for study via an optical microscope. A mechanism for the formation of the segregation is proposed. The primary causes of the segregation are shown to be surface tension, of the molten alloy, and the design of the component. The widespread belief that this form of segregation is a fundamental weakness of the squeeze casting process is therefore shown to be false. A theoretical model to a first approximation of the segregation, using the Young and Laplace equation is given. Using the pressure difference across a thin film the minimum web width, or radius of a corner, for no significant segregation can be found. The model is expanded and presented in a graphical form which is easy to understand and provides the designer with some tools to enable a sound casting to be produced. By sensible design the segregation phenomenon can be significantly reduced and in some cases eliminated completely.

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Smith, Paul David. "MEMS sensors exploiting the squeeze-film damping effect." Thesis, University of Sussex, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.430371.

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Papworth, Adam John. "Squeeze-casting of fibre reinforced metal matrix composites." Thesis, University of Liverpool, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.364201.

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Musson, Nicholas John. "The squeeze casting of aluminium alloys and composites." Thesis, University of Southampton, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.293609.

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Amberger, Claus-Peter. "Die Missbrauchskontrolle im Rahmen des aktienrechtlichen Squeeze-out /." Berlin : BWV Berliner Wissenschafts-Verl, 2007. http://deposit.d-nb.de/cgi-bin/dokserv?id=2992891&prov=M&dok_var=1&dok_ext=htm.

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Almurshedi, Ahmed. "Alternative plate deformation phenomenon for squeeze film levitation." Thesis, Brunel University, 2018. http://bura.brunel.ac.uk/handle/2438/17120.

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This thesis deals with a theoretical and an experimental exploration of squeeze film levitation (SFL) of light objects. The investigations aimed to find the important design parameters controlling this levitation mechanism and also to suggest an alternative way to implement SFL. The study, through computer modelling and experimental validation, focused on Poisson's contraction effect for generating SFL. A finite element model (ANSYS) was verified by experimental testing of five different plate designs. Each plate was subjected to a uniaxial plain stress by an arrangement of two hard piezoelectric actuators (PZT) bonded to the bottom of the plate and driven with DC or AC voltages. It was observed that pulsation of a dimple or crest shaped elastic deformation along the longitudinal axis in the central area of the plate was created because of Poisson's contraction. This Poisson's effect generated the squeeze-film between the plate and the levitated object. The separation distance between a floating lightweight object and the plate was analysed using computational fluid dynamics (ANSYS CFX) through creation of a modelling model for the air-film entrapped between the two interacting surfaces - a typical three-dimensional fluid-solid interaction system (FSI). Additionally, the levitation distance has been experimentally measured by a Laser Sensor. A satisfactory agreement has been found between model predictions and experimental results. Two levitation systems, one based on a horn transducer (Langevin type) and the other one in the form of a plain rectangular plate made of Aluminium and firmly fastened at both ends with a surface-mounted piezoelectric actuator, were compared in this thesis. Both devices were based on SFL mechanism. Evidently, the performances of both designs were greatly influenced by the design structure and in particular by the driving plate characteristics such as plate size and geometry as well as the driving boundary conditions. To this end, physical experiments were carried out and it was found that the device utilising horn-type transducer yields better levitation performance. Ultimately, the research explained the confusion between three approaches to non-contact levitation through literature review and also pointed out some essential parameters like piezoelectric actuators location, material of the driving structure, coupled-field between the actuators and the driving structure and the fluid-solid interface that was existed between the excited plate and the levitated object.

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Ashfold, Thomas Edward. "Work, time and rhythm : investigating contemporary 'time squeeze'." Thesis, University of Oxford, 2016. https://ora.ox.ac.uk/objects/uuid:c5fc9e00-fc82-4574-9099-3eb9d4e56bdb.

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In contemporary capitalist economies such as the UK, it is commonly held that an increasing number of people and households experience anxiety over time and symptoms of 'time squeeze'. Existing accounts of the character and causes of this phenomenon are rather one-dimensional and lacking in nuance, however. In part, this is because they typically lack any substantial theoretical engagement with the concept of time itself. Accordingly, this research aims to provide a more complex and contextual account of experiences of working time (both paid and unpaid), and to investigate how and why experiences of time squeeze vary between individuals and social groups. This is achieved by calling upon an enriched understanding of time, and employing an instrumental case study built around a set of 50 semi-structured interviews with employees working in Oxford University's central IT department and four of its constituent colleges. The empirical findings reveal that the (quantitative) extent and (qualitative) nature of participants' temporal anxieties vary with occupation, social class, gender, age and family status, as well as the importance of institutional and local context. Furthermore, they demonstrate that contemporary time squeeze is generated by a variety of causal mechanisms relating to the duration, tempo and timing of both paid employment and unpaid reproductive work, and their intersections with the personal, natural, social, institutional and technological rhythms that variously constitute everyday life.

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Cavey, Ryan Hale. "Design and Development of a Squeeze-Mode Rheometer for Evaluating Magneto-Rheological Fluids." Thesis, Virginia Tech, 2008. http://hdl.handle.net/10919/35139.

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This study aims to better understand the behavior of magnetorheological (MR) fluids operated in the non-conventional squeeze mode through the use of a custom designed rheometer. Squeeze mode is the least understood of the three operational modes of MR fluid and thus its potential has yet to be realized in practical applications. By identifying the behavior of MR fluid in this mode, the foundation for future development of MR technology will be laid.

Using the limited amount of literature available on squeeze-mode operation in conjunction with conventional principles associated with MR technology, a custom rheometer was designed and fabricated. A detailed account of the design considerations and background information on the fundamentals incorporated into the design are provided. The squeeze-mode rheometer was used to evaluate a variety of MR fluids to observe trends that may exist across fluids. Specifically, fluids of different ferrous particle volume fractions were considered.

Through testing, common trends in fluid stiffness were observed for multiple fluids tested with the squeeze-mode rheometer. When operated in squeeze mode, activated MR fluid has shown to provide substantial resistance to compressive loading, possibly making it attractive for low-displacement high-load systems. The primary observation from the tests is that the activated fluid's stiffness progressively increases over the duration of fluid operation. This phenomenon is due to severe carrier-fluid separation coupled with the formation of ferrous particle aggregate clumps in the fluid. This effect is further explored in this research.
Master of Science

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Booth, Charlotte. "Excavating paper squeezes : identifying the value of nineteenth and early twentieth century squeezes of ancient Egyptian monuments, through the collections of seven UK archives." Thesis, University of Birmingham, 2018. http://etheses.bham.ac.uk//id/eprint/8715/.

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This thesis provides a history of squeeze making in the discipline of Egyptology from its beginnings in the mid-nineteenth century to the continued use of tin squeezes in modern archaeological practice. The difference in approach to squeezes between the Egyptological and the Mediterranean disciplines will also be discussed. The analysis of the on-going value of squeezes produced more than a century ago highlights their importance for conservation and archival work as well as historical interpretation of the monuments of ancient Egypt. Using squeezes from seven archival collections in the UK as case studies, the accompanying catalogue and discussion highlights the information that can be obtained from the study of paper squeezes taken of Egyptian monuments in the nineteenth and early twentieth centuries. The squeezes studied highlight a number of inscriptions which have disappeared or have been extremely damaged since the squeezes were taken, demonstrating the value of these documents in reconstructing the monuments of the past. The overall objective is to encourage scholars to identify the importance these squeezes hold for epigraphic, social and conservation disciplines which acknowledging the damage caused in their production should not define how they are studied (or indeed not studied) in the modern world.

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Ast, Stefan [Verfasser]. "New approaches in squeezed light generation : quantum states of light with GHz squeezing bandwidth and squeezed light generation via the cascaded Kerr effect / Stefan Ast." Hannover : Technische Informationsbibliothek und Universitätsbibliothek Hannover (TIB), 2015. http://d-nb.info/1072062666/34.

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Smyth, William Samuel. "Non-classical atom field interactions in quantum optics." Thesis, Queen's University Belfast, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.318736.

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Kallweit, Andrej [Verfasser]. "Die angemessene Abfindung beim übernahmerechtlichen Squeeze-out / Andrej Kallweit." Baden-Baden : Nomos Verlagsgesellschaft mbH & Co. KG, 2014. http://d-nb.info/1108812597/34.

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Dissertations / Theses on the topic 'Squeegee'

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