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Dissertations / Theses on the topic 'Vnf modeling'

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Published: 14 March 2023

Last updated: 31 July 2025

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1

YUSUPOV, JALOLLIDDIN. "Formal assurance of security policies in automated network orchestration (SDN/NFV)." Doctoral thesis, Politecnico di Torino, 2020. http://hdl.handle.net/11583/2850616.

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2

Kline, Theodore S. "Broadband HF and VHF antenna design with terrain modeling." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1995. http://handle.dtic.mil/100.2/ADA305429.

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Thesis (M.S. in Electrical Engineering) Naval Postgraduate School, December 1995.<br>Thesis advisor(s): Rasler W. Smith, R.W. Adler. "December 1995." Includes bibliographical references. Also available online.

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3

Overstreet, William Patton. "VHF bipolar transistor power amplifiers: measurement, modeling, and design." Diss., Virginia Polytechnic Institute and State University, 1986. http://hdl.handle.net/10919/71166.

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Widely used design techniques for radio frequency power amplifiers yield results which are approximate; the initial design is usually refined by applying trial-and-error procedures in the laboratory. More accurate design techniques are complicated in their application and have not gained acceptance by practicing engineers. A new design technique for VHF linear power amplifiers using bipolar junction transistors is presented in this report. This design technique is simple in its application but yields accurate results. The design technique is based upon a transistor model which is simple enou

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4

Najm, Riyadh K. "Wire-grid modelling of glass-mounted vehicular antennas at VHF." Thesis, University of Liverpool, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.239950.

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5

Miller, Robert W. "Modeling methodology and data throughout analysis of a VHF land mobile radio network." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0002/MQ44853.pdf.

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6

Zhang, Aibin. "CFD Modeling and Optimization of Primary sedimentation tank." Thesis, KTH, Vattendragsteknik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-217116.

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In this project, the flow field characteristics of the simplified 2D rectangular primary sedimentation tank in Syvab wastewater treatment plant were achieved by a transient water-air two phases finite-volume method, applying Volume-Of-Fluid (VOF) model. RNG k-ε turbulence model was also employed to calculate the turbulent kinetic energy and its dissipation rate. The undesired hydraulic phenomenon for solid sedimentation was detected in original tank. To reduce the velocity and turbulence intensity of the influent, two categories of optimization methods were proposed, which are installing the b

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7

Thiele, Roman. "Modeling of Direct Contact Condensation With OpenFOAM." Thesis, KTH, Reaktorteknologi, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-49825.

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Within the course of the master thesis project, two thermal phase change models for direct contact conden-sation were developed with different modeling approaches, namely interfacial heat transfer and combustionanalysis approach.After understanding the OpenFOAM framework for two phase flow solvers with phase change capabilities,a new solver, including the two developed models for phase change, was implemented under the name ofinterPhaseChangeCondenseTempFoam and analyzed in a series of 18 tests in order to determine the physicalbehavior and robustness of the developed models. The solvers use a

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Abtahi, Sayyed Mohammad. "Airborne Gravity Gradient, Magnetic and VLF datasets : Case studies of modelling, inversion and interpretation." Doctoral thesis, Uppsala universitet, Geofysik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-300126.

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Northern Sweden is one of the largest hosts for mineral resources in Europe and always has been an interesting area for researchers from various disciplines of Earth sciences. This dissertation is a comprehensive summary of three case study papers on airborne VLF, gravity gradient and magnetic data in the area. In the first paper, tensor VLF data is extracted from an old data set which contains only the total and the vertical magnetic components. The anomalous part of the horizontal magnetic field components is computed by a Hilbert transform of the vertical magnetic field. The normal part of

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9

Toninelli, Paolo. "Two-phase heat transfer in minichannels: modeling and heat pump applications." Doctoral thesis, Università degli studi di Padova, 2017. http://hdl.handle.net/11577/3425359.

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Nowadays there is an increasing demand for compact devices with high performance in heating and cooling applications; a compact geometry permits to have a lower charge of refrigerant as compared to conventional HX. The present research activity is focused on the analysis of condensation phenomena inside a single minichannel and on the application of minichannels technology for condensers and evaporators in heating and cooling systems. When the inner diameter decreases, new parameters can influence in a significant way the two-phase heat transfer. Nowadays power

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Thunell, Rasmus. "Groundwater flow paths in fractured crystalline bedrock : Electromagnetic VLF measurements and modelling of a groundwater basin in Svanberga, Sweden." Thesis, KTH, Hållbar utveckling, miljövetenskap och teknik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-231983.

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Sweden is a country with a relatively high number of private wells, where about 1.2 million inhabitants in permanent housing and an equal amount in summer housing relies on private wells as their drinking water supply. At the same time the market for drinking water treatment products is unregulated regarding quality and requirements are needed. A testing facility with the aim of providing quality certifications as well as sustainability- and efficiency- tests of small scale drinking water treatment techniques is under development and located in a decommissioned groundwater treatment plant in S

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Jiang, Wenbiao. "Simulation du bullage dans un photobioréacteur." Thesis, Université Paris-Saclay (ComUE), 2018. http://www.theses.fr/2018SACLC086/document.

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Au cours des dernières années, la culture de microalgues est largement étudiée pour produire des biocarburants et d’autres produits de valeur en fixant le dioxyde de carbone de l’atmosphère, afin d’atténuer simultanément les effets du changement climatique et de réduire la dépendance à l’égard des carburants fossiles. En comparaison avec les systèmes ouverts, les photobioréacteurs fermés sont davantage utilisés en laboratoire, car ils permettent de contrôler avec précision les facteurs environnementaux tels que le pH, la concentration en éléments nutritifs, etc. Le principe de fonctionnement d

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SORIA, MIJAIL FEBRES. "THREE DIMENSIONAL MODELING OF A SINGLE UNIT SLUG IN A HORIZONTAL PIPELINE WITH THE VOF MODEL." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2009. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=15125@1.

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COORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR<br>O constante crescimento na demanda de combustíveis fósseis e as últimas descobertas de petróleo no Brasil têm tornado a modelagem de escoamentos multifásicos em tubulações e equipamentos na indústria do Petróleo numa tarefa crucial. Dentro as configurações possíveis que o escoamento multifásico pode adotar, o regime das golfadas possui uma enorme relevância devido às suas características intermitentes e seus fortes gradientes de pressão produzidos nas tubulações por onde escoa. Neste trabalho, estuda-se numericamente, com o método

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13

Guo, Dongzhi. "Design, Analysis, Modeling and Testing of a Micro-scale Refrigeration System." Research Showcase @ CMU, 2014. http://repository.cmu.edu/dissertations/450.

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Chip scale refrigeration system is critical for the development of electronics with the rapid increase of power consumption and substantial reduction of device size, resulting in an emergent demand on novel cooling technologies with a high efficiency for the thermal management. In this thesis, active refrigeration devices based on Stirling cycle and an electrocaloric material, are designed and investigated to achieve a high cooling performance. Firstly, a new Stirling micro-refrigeration system composed of arrays of silicon MEMS cooling elements is designed and evaluated. The cooling elements

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14

Teng, Penghua. "CFD MODELLING OF TWO-PHASE FLOWS AT SPILLWAY AERATORS." Licentiate thesis, KTH, Vattendragsteknik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-202392.

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Due to the high-speed flow in a chute spillway, cavitation damages often occur. This undesired phenomenon threatens the safety of the structure. For the purpose of eliminating the damages, an aerator is often installed in the spillway. To understand its characteristics, physical model tests are a popular method. To complement the model tests, computation fluid dynamics (CFD) simulations are used to study aerator flows. To represent the two-phase flows, multiphase models should be employed. This thesis examines two of them, namely, the Volume-Of-Fluid model (VOF) and Two-Fluid model. Based on t

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Pabon, Sanclemente Miguel Alejandro. "A Comparative Study of the Structural Features and Kinetic Properties of the MoFe and VFe Proteins from Azotobacter Vinelandii." DigitalCommons@USU, 2009. https://digitalcommons.usu.edu/etd/233.

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Biological nitrogen fixation is accomplished in the bacterium Azotobacter vinelandii by means of three metalloenzymes: The molybdenum, vanadium, and iron-only nitrogenase. The knowledge regarding biological nitrogen fixation has come from studies on the Mo-dependent reaction. However, the V- and Fe-only-dependent reduction of nitrogen remains largely unknown. By using homology modeling techniques, the protein folds that contain the metal cluster active sites for the V- and Fe-only nitrogenases were constructed. The models uncovered similarities and differences existing among the nitrogenases r

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16

Axelsson, Johan, and Roger Knutsson. "Numerical modeling of a slotted flip bucket spillway system – The Shibuya Hydropower Project." Thesis, KTH, Vattendragsteknik, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-96227.

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CFD is today a big part of the design process in hydraulic engineering and is more economical and time efficient than traditional scale models. But, there are still issues concerning the agreement with scale models in large and complex geometries. In this degree project a high head, five channeled, slotted flip bucket spillway system is analyzed with the CFD software FLUENT and compared with existing scale model results. The sought hydraulic parameters in each channel were the discharge capacity, the pressure distribution and the throw distance from the flip buckets. The discharge capacity and

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17

Ramasetti, E. K. (Eshwar Kumar). "Modelling of open-eye formation and mixing phenomena in a gas-stirred ladle for different operating parameters." Doctoral thesis, Oulun yliopisto, 2019. http://urn.fi/urn:isbn:9789526223568.

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Abstract In ladle metallurgy, gas stirring and the behaviour of the slag layer are very important for alloying and the homogenization of the steel. When gas is injected through a nozzle located at the bottom of the ladle into the metal bath, the gas jet exiting the nozzle breaks up into gas bubbles. The rising bubbles break the slag layer and create an open-eye. The size of the open-eye is very important as the efficiency of the metal-slag reactions depend on the interaction between the slag and steel created during the stirring process, and information about the position and size of the open-

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18

Banola, S. "Some characteristics of ionospheric irregularities at low latitudes deduced from VHF scintillation measurements." Thesis, IIG, 2001. http://localhost:8080/xmlui/handle/123456789/1574.

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19

Wallin, Adéle. "Structural intrusion, flow disturbance and spillway capacity : CFD modeling of the Torpshammar dam." Thesis, Uppsala universitet, Elektricitetslära, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-369319.

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At the Torpshammar dam two rectangular beams are situated upstream of the spillway gates to stabilize the sidewalls holding the embankment of the dam. A computational fluid dynamics (CFD) simulation of the dam with the bottom outlets open was made to investigate how the flow and discharge capacity is affected by the beams. The results can be used to avoid unexpected consequences due to turbulence caused by the beams, make the beams strong enough to hold the pressure from the flow and get an estimation of the discharge capacity with the beams. Turbulence is one of the hardest things to simulate

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20

Da, Riva Enrico. "Two-phase Heat Transfer in Minichannel Heat Exchangers: Heat Pump Applications, Design, Modelling." Doctoral thesis, Università degli studi di Padova, 2009. http://hdl.handle.net/11577/3426130.

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Refrigerant charge minimization is one of the most important targets for heating and air conditioning applications when using natural refrigerants like hydrocarbons or ammonia to cope with the new environmental challenges. Some applications of minichannels for charge minimization in heat pumps are presented and discussed in this thesis. The design of an innovative condenser, an evaporator and an internal heat exchanger is presented. These devices are shell-and-tube heat exchangers using 2 mm i.d. minichannels and realized for the use with propane. Computational procedures based on empirical

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21

Monaco, Marina. "Wave action on shallow water and applications to coastal hazard." Doctoral thesis, Universita degli studi di Salerno, 2010. http://hdl.handle.net/10556/127.

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2008-2009<br>The mechanics of wave breaking in shallow water has been a major research field for many years, and a very large number of published results are available. No attempt is made here to review the whole literature. Some interesting – if somewhat outdated - descriptions of waves breaking on beaches are presented by Peregrine (1983), Battjes (1988) or Liberatore-Petti (1992). In fact, the most important process in the near coast zone of the shoreline motion is wave breaking. Some waves break in shallow water, some of them break at the water’s edge and in other circumstances wa

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22

Fenni, Ines. "Efficient domain decomposition methods for electromagnetic modeling of scattering from forest environments." Thesis, Paris 6, 2014. http://www.theses.fr/2014PA066264/document.

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Cette thèse porte sur la modélisation et l’analyse de la propagation électromagnétique dans un milieu forestier dans les bandes VHF et UHF. L’objectif principal est le développement d’un modèle numérique "full-wave" tridimensionnel de diffusion par la forêt permettant de caractériser l’interaction d’une onde électromagnétique avec un milieu forestier. Un tel modèle s’avère, actuellement, un outil indispensable à l’analyse des mesures radar pour l’étude des paramètres caractéristiques de la forêt tels que la biomasse forestière, la hauteur des arbres et leur densité. La complexité numérique de

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23

Sebastia-Saez, J. Daniel. "CFD modelling of post-combustion carbon capture with amine solutions in structured packing columns." Thesis, Cranfield University, 2016. http://dspace.lib.cranfield.ac.uk/handle/1826/10024.

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The scope of the present thesis is the development of a Computational Fluid Dynamics model to describe the multiphase flow inside a structured packing absorber for postcombustion carbon capture. The work focuses mainly on two flow characteristics: the interface tracking and the reactive mass transfer between the gas and the liquid. The interface tracking brings the possibility of studying the liquid maldistribution phenomenon, which strongly affects the mass transfer performance. The development of a user-defined function to account for the reactive mass transfer between phases constitutes the

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Ha, Oai The. "Modeling and Numerical Investigation of Hot Gas Defrost on a Finned Tube Evaporator Using Computational Fluid Dynamics." DigitalCommons@CalPoly, 2010. https://digitalcommons.calpoly.edu/theses/400.

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Defrosting in the refrigeration industry is used to remove the frost layer accumulated on the evaporators after a period of running time. It is one way to improve the energy efficiency of refrigeration systems. There are many studies about the defrosting process but none of them use computational fluid dynamics (CFD) simulation. The purpose of this thesis is (1) to develop a defrost model using the commercial CFD solver FLUENT to simulate numerically the melting of frost coupled with the heat and mass transfer taking place during defrosting, and (2) to investigate the thermal response of the e

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Shao, Zhiyu S. "TWO-DIMENSIONAL HYDRODYNAMIC MODELING OF TWO-PHASE FLOW FOR UNDERSTANDING GEYSER PHENOMENA IN URBAN STORMWATER SYSTEM." UKnowledge, 2013. http://uknowledge.uky.edu/ce_etds/5.

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During intense rain events a stormwater system can fill rapidly and undergo a transition from open channel flow to pressurized flow. This transition can create large discrete pockets of trapped air in the system. These pockets are pressurized in the horizontal reaches of the system and then are released through vertical vents. In extreme cases, the transition and release of air pockets can create a geyser feature. The current models are inadequate for simulating mixed flows with complicated air-water interactions, such as geysers. Additionally, the simulation of air escaping in the vertical dr

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Brochier, Felipe Osmar Berwanger. "Otimização de um condicionador de ar do tipo split com vazão variável de refrigerante." Universidade do Vale do Rio dos Sinos, 2014. http://www.repositorio.jesuita.org.br/handle/UNISINOS/4619.

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Submitted by Fabricia Fialho Reginato (fabriciar) on 2015-07-23T01:11:46Z No. of bitstreams: 1 FelipeBrochier.pdf: 2248315 bytes, checksum: 51a12fbb2e530bf08f1847557932b381 (MD5)<br>Made available in DSpace on 2015-07-23T01:11:46Z (GMT). No. of bitstreams: 1 FelipeBrochier.pdf: 2248315 bytes, checksum: 51a12fbb2e530bf08f1847557932b381 (MD5) Previous issue date: 2014-02<br>Nenhuma<br>Este trabalho tem como objetivo otimizar o custo operacional dependente dos parâmetros de vazão de ar do condensador, número de aletas e de circuitos do condensador, frequência do compressor e parâmetros do dispo

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Akel, Junior Alberto Fares. "Modelagem de propagação subionosférica de ondas de frequência muito baixa." Universidade Presbiteriana Mackenzie, 2015. http://tede.mackenzie.br/jspui/handle/tede/1529.

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Made available in DSpace on 2016-03-15T19:38:53Z (GMT). No. of bitstreams: 1 ALBERTO FARES AKEL JUNIOR.pdf: 5112998 bytes, checksum: f18fc33d2f9508c3ec265c0efa016b43 (MD5) Previous issue date: 2015-08-21<br>Fundação de Amparo a Pesquisa do Estado de São Paulo<br>We study the behavior of the Earth-ionosphere waveguide through the modeling of the propagation of very low frequency radio waves (VLF). We use the computational model LWPC (Long Wave Propagation Capability) to estimate changes in amplitude and phase of the VLF signals detected by the SAVNET network (South America VLF NETwork), and t

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Kulkarni, Yash. "Theoretical and numerical modelling of three-phase dynamic contact line and atomisation." Electronic Thesis or Diss., Sorbonne université, 2025. http://www.theses.fr/2025SORUS036.

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La ligne de contact mobile triphasée est connue pour avoir une singularité de force au point triple de la ligne de contact dans la condition limite traditionnelle sans glissement. Un remède à cette singularité est de permettre au fluide d'avoir un petit glissement à la surface fluide-solide. Cette condition limite de glissement de Navier est connue pour résoudre la singularité de force. Dans la première partie de la thèse, nous commençons par montrer analytiquement les propriétés de régularité de trois conditions limites de type glissement, le glissement de Navier (NBC), le super glissement et

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Cuggia, Renaud. "MODÉLISATION D'ANTENNES TRÈS BASSES FRÉQUENCES (VLF/LF) : étude de l'influence de la structure, des composants associés et de l'environnement en vue de leur optimisation." Phd thesis, Université de Nice Sophia-Antipolis, 2010. http://tel.archives-ouvertes.fr/tel-00523630.

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Les télécommunications très basses fréquences (Very Low Frequency/Low Frequency) sont utilisées pour les communications militaires à couverture mondiale avec des sous-marins en plongée. La simulation de ces antennes nécessite l'utilisation de méthodes numériques bien souvent en limite de leur domaine de validité. L'objectif de la thèse est de développer un outil de modélisation globale des structures antennaires VLF/LF [3-300 kHz] prenant en compte l'environnement proche tels que les isolateurs, les structures de soutien, le plan de sol, les bâtiments annexes, ... Une première partie est consa

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Gapillout, Damien. "Développement de bancs de tests dédiés à la modélisation comportementale d’ampliﬁcateurs de puissance RF et micro-ondes". Thesis, Limoges, 2017. http://www.theses.fr/2017LIMO0071/document.

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Le travail présenté dans ce manuscrit a pour objet l’étude et le développement d’un banc de caractérisation généraliste appliqué à l’extraction du modèle comportemental d’ampliﬁcateur TPM-NIM (Two-Path Memory Nonlinear Integral). Ce modèle qui dispose d’une des architectures les plus abouties au laboratoire XLIM requiert une instrumentation microonde haut de gamme, très onéreuse, hors de portée de la majorité des concepteurs pour sa mise en œuvre expérimentale. L’objectif est donc de proposer des principes de mesure originaux permettant d’identiﬁer le modèle TPM-NIM avec une instrumentation st

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Khallahle, Jack Buckhill. "Numerical Simulation of Flow Parameters in Stratified Gas-Liquid Flow in a Horizontal Pipe." Thesis, The University of Sydney, 2022. https://hdl.handle.net/2123/29931.

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The transportation of gas-liquid mixtures in horizontal pipes as two-phase stratified flow is examined using computational fluid dynamics (CFD) method. The design of these pipelines requires accurate prediction of flow parameters such as pressure drop and liquid holdup. Many empirical correlations have been developed in the last 70 years and are well documented in the literature to obtain these parameters using experimental, analytical and numerical methods. In this investigation, the numerical method based on CFD code-FLUENT is used as an alternative to the experimental method to obtained

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Politis, Konstantinos. "Développement de modèles numériques de tension superficielle pour la simulation d'écoulements avec interface à l'aide d'une formulation multi-fluides." Thesis, Ecole centrale de Nantes, 2016. http://www.theses.fr/2016ECDN0021.

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Les méthodes de lubrification par injection d'air sont considérées par la communauté scientifique comme la principale percée technologique à venir pour la réduction de la trainée des navires de commerce. A cette fin, il est impératif de modéliser finement les phénomènes physiques en jeu dans la lubrification par injection d'air, qui intègrent la représentation précise de la tension superficielle, des instabilités d'interface et des écoulements avec entraînement d'air. Au cours de ce travail, nous nous sommes attachés au développement d'outils de programmation, de schémas de reconstruction d'in

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Park, Jangho. "Efficient Global Optimization of Multidisciplinary System using Variable Fidelity Analysis and Dynamic Sampling Method." Diss., Virginia Tech, 2019. http://hdl.handle.net/10919/91911.

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Work in this dissertation is motivated by reducing the design cost at the early design stage while maintaining high design accuracy throughout all design stages. It presents four key design methods to improve the performance of Efficient Global Optimization for multidisciplinary problems. First, a fidelity-calibration method is developed and applied to lower-fidelity samples. Function values analyzed by lower fidelity analysis methods are updated to have equivalent accuracy to that of the highest fidelity samples, and these calibrated data sets are used to construct a variable-fidelity Kriging

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Annerstål, Viktor, and Peter Ottosson. "Modellering och simulering av Multiantennsystem avsett för litet fartyg." Thesis, KTH, Skolan för informations- och kommunikationsteknik (ICT), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-205347.

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Within the military there is great need for reliable communication between vehicles. During the planning and construction of a military RIB, Rigid-hulled Inflatable Boat, it is important to design an efficient antenna system that does not deteriorate out of disorder. It must also be ensured that the antennas transmitted power does not stay in the RIB boat. We have been given assignment to model and simulate a proposed antenna system and assess which tool is best suitable for the task. To analyze the antenna system we will look at the radiated electrical field together with the reflectionand EM

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Peña, Monferrer Carlos. "Computational fluid dynamics multiscale modelling of bubbly flow. A critical study and new developments on volume of fluid, discrete element and two-fluid methods." Doctoral thesis, Universitat Politècnica de València, 2017. http://hdl.handle.net/10251/90493.

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The study and modelling of two-phase flow, even the simplest ones such as the bubbly flow, remains a challenge that requires exploring the physical phenomena from different spatial and temporal resolution levels. CFD (Computational Fluid Dynamics) is a widespread and promising tool for modelling, but nowadays, there is no single approach or method to predict the dynamics of these systems at the different resolution levels providing enough precision of the results. The inherent difficulties of the events occurring in this flow, mainly those related with the interface between phases, makes that

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Dimou, Konstantinos. "Améliorations de l'accès paquet en sens montant du WCDMA." Phd thesis, Télécom ParisTech, 2003. http://pastel.archives-ouvertes.fr/pastel-00000671.

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Les systèmes de 3G offrent de nouveaux services support (bearer services) à plus hauts débits pour les modes de transmission "paquet". Ces services vont coexister avec la voix (ou d'autres services temps réels), des scénarios de trafic mixte, voix et données, doivent être envisagés. La norme UMTS permet effectivement aux utilisateurs d'avoir plus d'un service activé simultanément. Les différentes classes de trafic augmentent la complexité de la gestion des ressources radios. Dans ce contexte, deux types de fonctions sont étudiés: l'allocation de TFCI et l'ordonnancement de paquets. Leur impact

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Ψαχούλιας, Γεώργιος. "Ηλεκτρομαγνητική μοντελοποίηση στις VHF και UHF περιοχές συχνοτήτων". Thesis, 2008. http://nemertes.lis.upatras.gr/jspui/handle/10889/846.

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Στόχος της παρούσας διπλωματικής εργασίας είναι η ηλεκτρομαγνητική μοντελοποίηση υπό βρoχόπτωση στις VHF και UHF περιοχές συχνοτήτων. Προκειμένου να εξαχθούν συμπεράσματα για την ποιότητα των παρεχόμενων υπηρεσιών (κυτταρική και δορυφορική τηλεφωνία, μετάδοση τηλεοπτικών σημάτων) προσδιορίζονται η ισχύς λήψης και μία σειρά από παραμέτρους.<br>The aim of this master thesis is the RF modeling during rainfall for the VHF and UHF ranges. In order to infer conclusions for the quality of the supplied services (cellular and satellite telephony, transmission of television signals) the received power

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Tsai, Wang-Lin, and 蔡旺霖. "Plasma Diagnostics and Kinetic Modeling on VHF PECVD of Microcrystalline Silicon." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/67898814650625917215.

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碩士<br>中原大學<br>化學工程研究所<br>99<br>In this study, the plasma diagnostics tools (including actinometrics OES and QMS) were used to investigate the influences of operating parameters on intrinsic layer deposition process of μc-Si:H thin film solar cell in parallel-plate PECVD system with an excitation frequency of 40.68 MHz (VHF). The diagnostics results were correlated to deposition rate and crystalline fraction of deposited silicon films. A combination of experimental diagnostics and computational modeling was utilized to understand the main reaction mechanism in the plasma. The plasma diagnostic

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Metello, Daniela Filipa Figueiredo Marques. "Modeling, Simulation and Experimental Validation of PVDF-based Electroactive Actuators." Master's thesis, 2020. http://hdl.handle.net/10316/93993.

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Trabalho de Projeto do Mestrado Integrado em Engenharia Biomédica apresentado à Faculdade de Ciências e Tecnologia<br>Nos últimos 20 anos, os polímeros electroactivos (EAPs) têm recebido mais atenção no mundo dos mecanismos de actuação. O termo "electroactivo" significa que o polímero é electricamente activo ou reactivo, ou seja, que terá uma resposta mecânica a um estímulo eléctrico. Como qualquer polímero, este é conhecido por ser leve e fácil de processar. Para além disso, os EAPs são resistentes e capazes de produzir grandes tensões de actuação, quando comparados com actuadores convenciona

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Tsai, I.-Long, and 蔡逸龍. "Measurement and Modeling of TV-Band (VHF/UHF) Propagation in the middle region of Taiwan." Thesis, 1995. http://ndltd.ncl.edu.tw/handle/40094070068225775536.

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碩士<br>國立交通大學<br>電信研究所<br>83<br>In this report, field strength measurements of TV-Band (UHF/VHF) propagation in the middle region of Taiwan have been conducted. The measurement procedure follows FCC's regulations. Meanwhile, a theoretical model, based on geometric optics and knife-edge diffraction theory has been developed. By comparing the measured field strength with that precdicted by FCC's, CCIR's or the theorectical model, it shows that FCC and CCIR have better predicting accuracy in th

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"The geophysical very low frequency electromagnetic (VLF-EM) method: effects of topography and surface water investigated with simulations and field measurement." Thesis, 2015. http://hdl.handle.net/10388/ETD-2015-03-2020.

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The Very Low Frequency Electromagnetic (VLF-EM) method, which enables surveying without contact with the ground, is suitable for ground surveys in a wide area and has been used in mapping geology for decades. The technique makes use of signal radiation from military navigation radio transmitters operating in the frequency range of 15-30 kHz. When the electromagnetic wave impinges on the surface it is both reflected back into the air and refracted into the earth. By measuring the shifted reflected magnetic field relative to the primary field, subsurface structures can be constrained. Although

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Wang, Wei-Chao, and 王威超. "A Study on the Analysis and Modeling of Maritime VHF Wave Propagation- Based on AIS Sea Trials in Coastal Waters of Taiwan." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/89366344995221730801.

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碩士<br>國立海洋大學<br>導航與通訊系碩士班<br>91<br>Automatic Identification System (AIS), which integrates the mobile communication and satellite positioning technologies, has great potential in contributing to navigation safety and maritime security. All vessels subject to the Safety of Life at Sea Convention（SOLAS）are required to be fitted with AIS within a very tight schedule. It is therefore of urgency needs of AIS researches to support the planning and implementations of shore-based AIS facilities and services. However, as compared with the situation on land, field measurements with sea trials are really

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Tran, Nhi. "MONASH-VN: Development of a dynamic CGE model for the Vietnamese economy and analysis of structural changes during 1996-2003." Thesis, 2007. https://vuir.vu.edu.au/29422/.

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This thesis is concerned with the construction and application of MONASH-VN (hereafter MVN), a large-scale dynamic computable general equilibrium (CGE) model of Vietnam. The model is designed to provide the capacity for not only detailed analysis of economic policies but also forecasts and analyses of economic history. After constructing the model, I use it to conduct an analysis of the structural changes in the Vietnamese economy over the period 1996-2003. This was a period of rapid growth of around seven percent per annum, despite adverse shocks such as the Asian economic crisis in the late

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Γεωργόπουλος, Ιωάννης. "Ηλεκτρομαγνητική μοντελοποίηση στην VHF και UHF περιοχή ραδιοφάσματος για εφαρμογές στα σύγχρονα ασύρματα δίκτυα". Thesis, 2010. http://nemertes.lis.upatras.gr/jspui/handle/10889/4345.

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Στις σύγχρονες τηλεπικοινωνίες, χρησιμοποιείται μια μεγάλη γκάμα από RF μοντέλα, για τον υπολογισμό την μέσης τιμής ισχύος του σήματος εκπομπής για δεδομένη απόσταση από τον πομπό και για δεδομένη συχνότητα. Στις διεργασίες αυτές , επιδρούν στο δικό τους βαθμό διάφορες παράμετροι τοπολογικού (πληθυσμός , τύπος εμποδίων, πυκνότητα εμποδίων) και γεωγραφικού (μορφολογία εδάφους, υγρασία, διαμόρφωση χώρου) χαρακτήρα, αλλά και χαρακτηριστικά των πομποδεκτών ( συνήθως το ύψος και το κέρδος των κεραιών). Στις περισσότερες περιπτώσεις οι απώλειες όδευσης (Path Loss όπως είναι γνωστές στη διεθνή βιβ

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