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Dissertations / Theses on the topic 'Reflection coefficient'

Author: Grafiati

Published: 4 June 2021

Last updated: 25 July 2025

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1

Bhalla, Gaurav Ph D. Massachusetts Institute of Technology. "Osmotic reflection coefficient." Thesis, Massachusetts Institute of Technology, 2009. http://hdl.handle.net/1721.1/51614.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Chemical Engineering, 2009.<br>Includes bibliographical references (leaves 149-152).<br>The presence of a discriminating barrier separating two solutions differing in concentration generates a net volume flux called osmotic flow. The simple case is of the ideal semi-permeable membrane which completely excludes the solute. The flow through such a membrane is directly proportional to the thermodynamic pressure drop less the osmotic pressure drop. For membranes which partially exclude the solute the osmotic contribution to flow is l

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2

Wang, Yang. "CdS Reflection Coefficient Determination via Photocurrent Spectroscopy." Bowling Green State University / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1219593815.

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3

Tuerxunjiang, Abulikemu. "FDTD measurement of the reflection coefficient associated with total internal reflection from gainy Lorentzian media." Pullman, Wash. : Washington State University, 2008. http://www.dissertations.wsu.edu/Thesis/Fall2008/A_Tuerxunjiang_120108.pdf.

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Thesis (M.S. in physics)--Washington State University, December 2008.<br>Title from PDF title page (viewed on July 10, 2009). "Department of Physics and Astronomy." Includes bibliographical references (p. 64-68).

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4

Cooper, James Roger. "A Multi-Wilkinson Power Divider Based Complex Reflection Coefficient Detector." Scholar Commons, 2010. https://scholarcommons.usf.edu/etd/1603.

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In the field of applied electromagnetics, there is always a need to create new methods for electrical characterization of materials, systems, devices, etc. Many applications need small and/or inexpensive equipment in performing these characterizations. The current method for making measurements of electrical properties at frequencies above 300 MHz, the transmission/reflection method, has severe limitations in these areas due large size and high price of the necessary equipment for making them. Therefore, presented herein is the conceptualization, design and analysis of a complex reflection coe

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5

Durnan, Gregory J. "Parasitic Feed Elements for Reflector Antennas." Thesis, Griffith University, 2005. http://hdl.handle.net/10072/368077.

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The use of parasitic wire dipoles are examined when placed in the proximity of a focused dipole feed in a parabolic reflector antenna. These parasitic elements are rotated around the feed dipole and a search is performed for the ideal positioning so as to yield maximum radiated power and main beam shift in order to develop a novel form of angle diversity. In addition a comparison is made between 2 element dipole feed structures and linearly and circularly polarised patch feed structures. In order to analytically model the structure, mutual coupling between feed elements is calculated taking in

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6

Pialucha, Tomasz Piotr. "The reflection coefficient from interface layers in NDT of adhesive joints." Thesis, Imperial College London, 1992. http://hdl.handle.net/10044/1/8364.

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7

Mainou, Gomez José Francisco. "Amplifier for optimal reflection Coefficient of ultrasound transducer : A study of op amp based circuits for ultrasound transducers, targeted for low reflection Coefficient, high gain, and low noise." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for elektronikk og telekommunikasjon, 2012. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-18347.

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Reverberation is defined as equally-spaced, bright linear echoes resulting from reflection from specular-type interfaces. They are provoked by the acoustic Impedance change between the tissue and transducer front surface. B. Angelsen developed a mathematical approach to correct this ultrasound artifact by coupling the ultrasound transducer with an ideal electrical load in order to obtain zero reflection coefficients on the transducer from face [1]. However, when analyzing Impedance spectroscopy this approach cannot be achieved by using passive electronics in most simulated cases. Active impeda

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8

Nguyen, Thinh H. "Study of Reflection Coefficient in Different Resistive States of HfO2-based RRAM." University of Cincinnati / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1535702700125043.

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9

Kulkarni, Mandar S. "Multi-coefficient Dirichlet Neumann type elliptic inverse problems with application to reflection seismology." Birmingham, Ala. : University of Alabama at Birmingham, 2009. https://www.mhsl.uab.edu/dt/2010r/kulkarni.pdf.

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Thesis (Ph. D.)--University of Alabama at Birmingham, 2009.<br>Title from PDF t.p. (viewed July 21, 2010). Additional advisors: Thomas Jannett, Tsun-Zee Mai, S. S. Ravindran, Günter Stolz, Gilbert Weinstein. Includes bibliographical references (p. 59-64).

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10

Schneck, Arne. "Bounds for optimization of the reflection coefficient by constrained optimization in hardy spaces." Karlsruhe Univ.-Verl. Karlsruhe, 2009. http://d-nb.info/995244383/04.

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11

Jurevičiūtė, Asta. "Šviesos atspindys nuo homogeninės anizotropinės aplinkos." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2007. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2007~D_20070816_171412-47555.

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Šiame darbe nagrinėjamas šviesos atspindžio parametrų priklausomybė nuo SbSI kristalo įvairių kristalografinių plokštumų atžvilgiu.Tai darboma sukurtos skaičiavimo programo spagalba.<br>On purpose about structure of the light, you must to make measurement of light reflections parameters. Following are outputting of equation of the Fresnel. Parameters of light reflection describe . In this work we finding following parameters with the help of the program “Mathematica”. And we finding the contingent on light incidence , rotate angle , anisotropy coefficient a.

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12

Доброжан, Олександр Анатолійович, Александр Анатольевич Доброжан, Oleksandr Anatoliyovych Dobrozhan, et al. "Optical Losses of Thin Solar Cells on the Basis of n-ZnS / p-CdTe and n-CdS / p-CdTe Heterojunctions." Thesis, Sumy State University Publishing, 2013. http://essuir.sumdu.edu.ua/handle/123456789/33898.

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The optical reflection and absorption losses in the accessory layers of solar cells based on n-ZnS / p- CdTe and n-CdS / p-CdTe heterojunctions are defined in this work. Aluminum doped zinc oxide is used as the front conductive layer material. It is shown that the replacement of traditional window material (CdS) for a wide-one (ZnS) leads to an increase in accessory solar cells layers transmittance. When the thickness of the window layers is 50 nm, the transmittance using ZnS windows with the wavelength of 380-500 nm is higher in 7-40 % than the corresponding value for CdS. At 300 nm for t

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13

Dobrozhan, O. A., T. O. Berestok, D. I. Kurbatov, A. S. Opanasyuk, N. M. Opanasyuk, and V. F. Nefedchenko. "Optical Losses of Thin Solar Cells on the Basis of n-ZnS / p-CdTe and n-CdS / p-CdTe Heterojunctions." Thesis, Sumy State University, 2013. http://essuir.sumdu.edu.ua/handle/123456789/35590.

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The optical reflection and absorption losses in the accessory layers of solar cells based on n-ZnS / p- CdTe and n-CdS / p-CdTe heterojunctions are defined in this work. Aluminum doped zinc oxide is used as the front conductive layer material. It is shown that the replacement of traditional window material (CdS) for a wide-one (ZnS) leads to an increase in accessory solar cells layers transmittance. When the thickness of the window layers is 50 nm, the transmittance using ZnS windows with the wavelength of 380-500 nm is higher in 7-40 % than the corresponding value for CdS. At 300 nm for

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14

Skarke, Adam D. "Application of chirp sonar acoustic reflection coefficient for sea floor sediment classification results from the Delaware Estuary /." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 109 p, 2008. http://proquest.umi.com/pqdweb?did=1459905621&sid=2&Fmt=2&clientId=8331&RQT=309&VName=PQD.

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15

Guell, David Charles. "The physical mechanism of osmosis and osmotic pressure--a hydrodynamic theory for calculating the osmotic reflection coefficient." Thesis, Massachusetts Institute of Technology, 1991. http://hdl.handle.net/1721.1/29859.

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16

Yang, Xin. "Study of the hydrogen-tungsten interaction for fusion : measurement of the atomic reflection coefficient by laser spectroscopy." Thesis, Aix-Marseille, 2017. http://www.theses.fr/2017AIXM0232.

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Les interactions plasma surface (PSI) sont considérées comme l'un des défis scientifiques majeurs de la fusion nucléaire magnétique contrôlée. L'interaction entre les isotopes d'hydrogène et les matériaux de l’enceinte à plasma tels que le tungstène revêt une importance particulière. Le coefficient de perte en surface des isotopes atomiques (γ) est un point clé dans les études PSI. Il peut donner des informations sur le recyclage de l'hydrogène atomique à la paroi et constitue ainsi un paramètre clé dans les modélisations des interactions plasma surface. Le but de ce projet est de déterminer l

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17

Li, Ye. "Propagation and reflection of pulse waves in flexible tubes and relation to wall properties." Thesis, Brunel University, 2011. http://bura.brunel.ac.uk/handle/2438/6554.

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The wall properties of the arteries play an important role in cardiovascular function. Stiffness of large artery is predictive of cardiovascular events. To understand the function of the cardiovascular system, special attention should be paid to the understanding of pulse wave propagation, because pulse waves carry information of the cardiovascular function, and provide information which can be useful for the prevention and diagnosis of diseases. This thesis presents a series of in vitro experimental studies of wave propagation, wave reflection and determination of mechanical properties of fle

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18

Yared, Hailegiorgis Dinagdae. "The possibility of utilizing the normal incidence reflection coefficient of acoustic waves to characterize and study porous granular layers." Thesis, KTH, Väg- och banteknik, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-92188.

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currently operational non-destructive testing methods for pavements have many drawbacks that need improvement. This thesis investigates the possibility of utilizing the normal incidence reflection coefficient of acoustic waves in characterizing and studying of porous granular materials. The reflection coefficient of acoustic waves carries information about the physical parameters of materials. The fouling process in ballast layer and the compaction progress in sand and road base layers are the main focus of this study. Simplified fluid equivalent models are used to characterize and study the g

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19

Raei, Mohammed. "The Shape Synthesis of Antenna Decoupling Surfaces." Thesis, Université d'Ottawa / University of Ottawa, 2021. http://hdl.handle.net/10393/42252.

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Although multi-element antenna (MEA) systems are already used in some modern wireless communication systems, the issue of mutual coupling between elements remains a challenge during MEA system design. Indeed, communications engineers continue to bemoan the fact that that the antenna elements are often still designed with such coupling as an afterthought. Thus, some authors have used the decoupling surface (DS) idea, whereby a separate DS is added to the MEA systems to reduce the above coupling. Whereas a DS may indeed lower the coupling levels between the elements of a given MEA system, it usu

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20

Buttarello, Karina Zoboli. "Análise da impedância acústica na gasolina." Universidade de São Paulo, 2003. http://www.teses.usp.br/teses/disponiveis/18/18135/tde-16022016-120602/.

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Este trabalho analisa a qualidade dos combustíveis derivados de petróleo através de suas propriedades acústicas, visando assim um monitoramento contínuo e instantâneo. Analisa a variação da impedância acústica da gasolina com acréscimo de vários componentes como: tolueno, óleo diesel, querosene e álcool anidro. Os resultados obtidos mostram uma variação significativa embora não linear da impedância acústica nos combustíveis derivados de petróleo com acréscimo de tais substâncias.<br>This work is related with research project focused on the development of low cost and robust quality monitoring

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21

Takamiya, Patrick Toyoki. "Approximation of the fast bottom reflection coefficient in the quadruplet expansion of the method of images in a wedge shaped ocean." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1994. http://handle.dtic.mil/100.2/ADA281644.

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22

Qiu, Zhiping. "Propagation en guide d'onde large : mesure par antennerie microphonique de la réflexion multimodale pour différentes extrémités." Thesis, Poitiers, 2017. http://www.theses.fr/2017POIT2278/document.

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L'étude expérimentale de la propagation et du rayonnement multimodal en guide large est abordée via des mesures par antennerie microphonique de la réflexion des modes pour différentes extrémités. Le banc expérimental est constitué d'un guide large fermé à une extrémité et débouchant sur différentes terminaisons à l'autre extrémité ; en paroi du guide sont branchées une source acoustique et deux antennes microphoniques. Chaque composant du banc est étudié pour améliorer les résultats de mesure. Une méthode de vérification des performances des haut-parleurs constituant la source et une méthode d

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23

GUARENA, NICOLO'. "Relevance of chemical and electrical phenomena to the semipermeable properties of bentonites." Doctoral thesis, Politecnico di Torino, 2021. http://hdl.handle.net/11583/2917998.

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24

Dai, Hui-Hui. "Reflection of solitary waves at a slope in various cases, and the generalized dressing method and its application to the integration of variable coefficient kdv equations." Thesis, University of Newcastle Upon Tyne, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.346409.

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25

Guzmán, Ediguer Enrique Franco. "Medição de propriedades viscoelásticas de líquidos por ultrassom." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/3/3152/tde-20082010-165311/.

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A medição das propriedades viscoelásticas de líquidos por ultrassom tem sido um tema de pesquisa importante desde meados do século XX, principalmente, pela possibilidade de realizar medições em tempo real da viscosidade. O método de medição baseia-se na determinação do coeficiente de reflexão complexo (magnitude e fase) de ondas de cisalhamento refletidas da interface definida entre um sólido e uma amostra líquida. Enquanto a medição da magnitude é relativamente simples e precisa, a medição da fase é muito difícil devido à forte dependência da temperatura, que gera uma incerteza muito grande.

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26

Coinchelin, David. "Mécanismes et modélisation de l'accumulation foliaire du nickel par l'hyperaccumulateur Leptoplax emarginata." Thesis, Vandoeuvre-les-Nancy, INPL, 2011. http://www.theses.fr/2011INPL010N/document.

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Des modèles prédictifs de prélèvement d’éléments traces métalliques (ETM) par des plantes hyperaccumulatrices sont à développer pour rendre la phytoextraction opérationnelle. Ce travail a pour objectif de développer, calibrer et valider un modèle biophysique combiné d’accumulation foliaire et de mise en solution du nickel lors de cultures de l’hyperaccumulateur Leptoplax emarginata sur un sol fertilisé et contaminé en Ni. Une partie de ce modèle intègre un facteur de bioconcentration lié à la transpiration (TSCF) qui caractérise le mode de transport principal du Ni à travers la racine et jusqu

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27

Johner, Albert. "Approche microscopique et macroscopique de la reflectivite d'interfaces." Université Louis Pasteur (Strasbourg) (1971-2008), 1988. http://www.theses.fr/1988STR13114.

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28

Yang, Can. "Time-lapse Analysis of Borehole and Surface Seismic Data, and Reservoir Characterization of the Ketzin CO2 Storage Site, Germany." Doctoral thesis, Uppsala universitet, Geofysik, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-163013.

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The CO2SINK (and CO2MAN) project is the first onshore CO2 storage project in Europe. The research site is located near the town of Ketzin, close to Potsdam in Germany. Injection started in June 2008, with a planned injection target of 100,000 tonnes of CO2. In February 2011, around 45, 000 tons of CO2 had been injected into the saline aquifer at an approximate depth of 630 m. This thesis focuses on time-lapse analysis of borehole seismic data, surface seismic data and reservoir characterization at the Ketzin site. Baseline Moving Source Profiling (MSP) data were acquired in the borehole Ketzin

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29

Tiikoja, Heiki. "Acoustic Characterization of Turbochargers and Pipe Terminations." Licentiate thesis, KTH, MWL Marcus Wallenberg Laboratoriet, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-92648.

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In search for quieter engines there is a need for a better understanding of the acoustic properties of engine intake and exhaust system components. Besides mufflers which have the purpose of reducing pressure pulses originating from the internal combustion (IC) engine, there are many components in a modern car exhaust and intake system, e.g., air-filters, coolers, catalytic converters, particulate filters - all having an effect on the pressure pulses or sound field in the system. In this work the focus is on the turbocharged IC-engine where both, sound scattering (reflection and transmission)

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30

Lesur, Benoît. "Validations de modèles numériques de grands réseaux pour l'optimisation d'antennes à pointage électronique en bande Ka." Thesis, Limoges, 2017. http://www.theses.fr/2017LIMO0111/document.

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L'essor des communications par satellites et des nouvelles technologies de l'information et de la communication conduisent à une demande croissante de la part des utilisateurs. Ainsi, afin de répondre à ces nouveaux besoins, des services proposant de la connectivité en vol pour les passagers des compagnies aériennes voient le jour. Les travaux présentés dans ce mémoire portent sur la réalisation de modèles numériques rigoureux de grands réseaux d'antennes destinés à couvrir ce champ applicatif. Après une mise en contexte et un rappel des contraintes liées aux réseaux d'antennes, des véhicules

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31

Maati, Amel. "Mise en œuvre de formalismes pour la modélisation de grands réseaux périodiques d'antennes." Thesis, Limoges, 2018. http://www.theses.fr/2018LIMO0009/document.

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Cette thèse se place dans le contexte général de la modélisation de réseaux d’antennes de grande taille, avec pour objectif d’atteindre un niveau de précision suffisamment élevé pour permettre une optimisation complète des performances et en particulier une amélioration de l’efficacité énergétique. Partant du constat que l’optimisation électromagnétique de grands réseaux représente un verrou si les couplages doivent être modélisés efficacement, cette thèse propose la mise en œuvre d’une méthode permettant la modélisation fine de grands réseaux d'antennes tout en réduisant les temps de calcul e

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32

Sheridan, Benedict. "The optical anisotropy of the Au(110) surface." Thesis, University of Liverpool, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.343707.

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Pometcu, Laura. "Matériaux et forme innovants pour l'atténuation en hyper fréquences." Thesis, Rennes 1, 2016. http://www.theses.fr/2016REN1S044/document.

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Les matériaux absorbants des ondes électromagnétiques sont des éléments importants pour l'évaluation de nombreux systèmes électroniques militaires mais également civils. Ces matériaux sont utilisés, par exemple, pour la réduction des interférences électromagnétiques (EMI) dans divers composants sans fils, la réduction de la surface équivalente radar (SER) ou comme absorbants à l'intérieur des chambres de mesures. C’est cette dernière application qui est visée par les travaux de cette thèse. L’objectif de mes travaux de thèse est d’optimiser des matériaux absorbants utilisés dans les chambres a

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34

YANG, LIUJING. "The measurement of antenna VSWR by means of a Vector Network Analyzer." Thesis, Linnéuniversitetet, Institutionen för fysik och elektroteknik (IFE), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-98287.

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The VSWR is an important entity when assessing the properties of an antenna. This report presents measurements of the VSWR, related to antennas, by means of a Vector Network Analyzer. The open/short/load calibration method is used as a preparation before the actual measurement in order to obtain accurate results. The way that the VSWR depends on frequency is illustrated by three measurment methods: direct measurement of the VSWR, by using 𝑆11, or by using the Smith chart. The results are compared and conclusions are drawn.

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35

Tobgay, Sonam. "Novel concepts for RF surface coils with integrated receivers." Link to electronic thesis, 2004. http://www.wpi.edu/Pubs/ETD/Available/etd-0419104-141545.

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36

Urbanec, Tomáš. "SPECIÁLNÍ METODY MIKROVLNNÝCH VEKTOROVÝCH MĚŘENÍ." Doctoral thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2008. http://www.nusl.cz/ntk/nusl-233416.

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Borocin, F. "(Derivation of) reflection/transmission coefficients for fluid-saturated poroelastic sediments." Thesis, University of Edinburgh, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.641793.

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The interpretation of reflection, transmission and conversion (RTC) coefficients in fluid-saturated porous rock is of utmost importance for the characterisation of hydrocarbon reservoirs. It has also been suggested that high-pressure pore-fluid is responsible for anomalously high (up to 0.15-0.25) values of reflection coefficients (deep crustal reflectors) in the lower crust, subduction zones and subglacial deforming sediments. In my thesis I consider the interaction of seismic waves at the interface between fluid-saturated poroelastic media, taking properly into account the effects of fluid-s

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38

Zhang, Bing. "Joint identification in structural waveguides using wave reflection and transmission coefficients." Thesis, University of Southampton, 2007. https://eprints.soton.ac.uk/50563/.

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The dynamic modelling of one-dimensional jointed structures is relevant to many engineering applications, such as pipe systems and beam networks in constructions. Currently available techniques are undermined by inadequate ability to model the joints and other discontinuities due to uncertainty in their properties. Measured modal data can be used to update joint models, but often with limited success. In this thesis a wave approach is employed to investigate the reflection and transmission coefficients of various joint models in structural waveguides. The reflection and transmission coefficien

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39

Ethier, Jonathan L. T. "Antenna Shape Synthesis Using Characteristic Mode Concepts." Thèse, Université d'Ottawa / University of Ottawa, 2012. http://hdl.handle.net/10393/23464.

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Characteristic modes (CMs) provide deep insight into the electromagnetic behaviour of any arbitrarily shaped conducting structure because the CMs are unique to the geometry of the object. We exploit this very fact by predicting a perhaps surprising number of important antenna metrics such as resonance frequency, radiation efficiency and antenna Q (bandwidth) without needing to specify a feeding location. In doing so, it is possible to define a collection of objective functions that can be used in an optimizer to shape-synthesize antennas without needing to define a feed location a priori. We d

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40

Oelke, Antonia [Verfasser]. "Estimating Reflection Coefficients: Theory and Application to Microseismic Waveform Data / Antonia Oelke." Berlin : Freie Universität Berlin, 2016. http://d-nb.info/1122111150/34.

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41

Kharrat, Mohamed. "Design and development of a torsional guided-waves inspection system for the detection and sizing of defects in pipes." Thesis, Ecully, Ecole centrale de Lyon, 2012. http://www.theses.fr/2012ECDL0016/document.

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Plusieurs industries manipulent des substances liquides et gazeuses qui circulent souvent dans de longues canalisations. La technique d'ondes guidées est couramment utilisée dans ce domaine. Cette technique est en progrès continu. Dans cette thèse, un système d'inspection a été conçu et développé. Il est basé sur des transducteurs piézoélectriques qui génèrent des ondes guidées de torsion pouvant se propager le long du tube testé. Les signaux réfléchis des défauts et singularités rencontrés sont détectés aussi par des capteurs piézoélectriques. Des simulations numériques utilisantpar la méthod

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42

Khalili, Nasser. "Application of Cepstral techniques to the measurement of reflection coefficients for dispersive systems." Thesis, University of Southampton, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.303060.

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43

Ducret, Fabrice. "Studies of sound generation and propagation in flow ducts." Licentiate thesis, Stockholm : Royal Institute of Technology, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4049.

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44

Fritz, Michael. "Mechanismen des radialen Volumenflusses und der radialen Permeation von Osmolyten in verzweigten Wurzeln junger Maispflanzen (Zea mays L.) und halmbürtigen Adventivwurzeln des Schilfes (Phragmites australis Trin. ex Steudel)." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, 2012. http://dx.doi.org/10.18452/16516.

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Der radiale Wasserfluss durch die feinen Seitenwurzeln von Schilf- und Mais ist vom radialen Teilchenfluss entkoppelt. Der radiale Wasserfluss wird bereits im Kortex der Wurzel durch den Protoplasten kontrolliert, da die Strömung auf dem apoplastischen Zellwandweg um die Protoplasten herum gegenüber der Strömung durch die Protoplasten nicht signifikant ist. Der radiale Reflexionskoeffizient der Wurzeln wird durch den Reflexionskoeffizient der Plasmamembran bestimmt. Die Feinwurzeln von Schilf- und Mais besitzen einen Reflexionskoeffizienten für Salze, Zucker, Zuckeralkohole und Polymere der

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Dvořák, Radek. "Širokopásmová vektorová měření." Doctoral thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2013. http://www.nusl.cz/ntk/nusl-233592.

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Thesis describing design and measurement of the vector reflectometer system based on six port principle. The expectations for precision measurement in wide bandwidth system are explained. Diode linearization problem is described and the calibration method especially designed for the wide band systems is explained. And finally several data processing methods for the final result decision are compared.

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Rämmal, Hans. "Studies of flow duct acoustics with applications to turbocharged engines." Doctoral thesis, KTH, MWL Marcus Wallenberg Laboratoriet, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-10590.

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A number of experimental and theoretical studies, performed in the field of technical flow duct acoustics are presented in this thesis. The acoustical methods treated are implemented on turbocharged IC-engines and engine gas exchange system components. A new method based on the well-known two-load technique has been developed. The method was applied to characterise the source data of various piston-engines with non-linear behaviour including a 6 cylinder turbo-charged truck diesel engine. The source characterisation results were compared to the results obtained using the linear two-load techni

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Jeyakumaran, R. "Some scattering and sloshing problems in linear water wave theory." Thesis, Brunel University, 1993. http://bura.brunel.ac.uk/handle/2438/5390.

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Using the method of matched asymptotic expansions the reflection and transmission coefficients are calculated for scattering of oblique water waves by a vertical barrier. Here an assumption is made that the barrier is small compared to the wavelength and the depth of water. A number of sloshing problems are considered. The eigenfrequencies are calculated when a body is placed in a rectangular tank. Here the bodies considered are a vertical surface-piercing or bottom-mounted barrier, and circular and elliptic cylinders. When the body is a vertical barrier, the eigenfunction expansion method is

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Weser, Robert. "Erfassung und Auswertung von Ultraschallechosignalen zur Charakterisierung konzentrierter disperser Stoffsysteme." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2015. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-158895.

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Die Charakterisierung von Dispersionen hat das Ziel, die Zusammensetzung und den Zustand von partikelhaltigen Stoffgemischen zu erfassen. Vor allem der Zustand der dispersen Phase (Partikel), der wiederum von der Größe und der Konzentration der Partikel bestimmt wird, ist in diesem Zusammenhang von besonderer Bedeutung. Neben optischen Verfahren, wie der Laserbeugung oder der Lichtstreuung, ist die Anwendung von akustischen Methoden vor allem dann sinnvoll, wenn die zu untersuchenden dispersen Stoffgemische opak und optische Methoden nur noch eingeschränkt (nach Verdünnung) anwendbar sind. Der

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Berry, Simon James. "Microwave surface waves on metasurfaces with planar discontinuities." Thesis, University of Exeter, 2014. http://hdl.handle.net/10871/15283.

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The work presented within this thesis details the experimental investigation of the surface waves supported on metasurfaces. Particular attention has been given to the reflection of these surface waves from planar discontinuities associated with these metasurfaces. Various experimental techniques have been developed throughout this work to characterise surface wave supporting metasurfaces. These include a new technique for measuring the dispersion of surface waves supported on metasurfaces, characterisation of the near-field associated with the surface waves, a device for launching planar phas

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Aivaliotis, Alexios. "Propagation et diffusion des ondes au niveau macroscopique des métamatériaux limites via le modèle micromorphique relaxé." Thesis, Lyon, 2019. http://www.theses.fr/2019LYSEI073.

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Les métamatériaux mécaniques microstructurés attirent de plus en plus l'attention de la communauté scientifique et technique. Nous choisissons une approche qui évoque la théorie classique de l'élasticité : celle de la mécanique des milieux continus enrichie. Le but de cette thèse est d'utiliser le nouveau modèle de continuité enrichie appelé modèle micromorphique relaxé détendu afin d'étudier la propagation des ondes et les phénomènes de diffusion aux interfaces entre matériaux et métamatériaux. Lorsqu'il s'agît d'étudier les propriétés de diffusion de structures de taille finie, il devient di

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