Dissertations / Theses: 'Parameters calculation'

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Grainger, Roy Gordon. "The calculation of cloud parameters from AVHRR data." Thesis, University of Auckland, 1990. http://hdl.handle.net/2292/2446.

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This thesis deals with the electromagnetic radiation that is reflected from and emitted by a clear or cloudy terrestrial atmosphere. Calculations are performed in order to estimate the radiation exitant to space in the visible, the near visible, and the two infrared windows at approximately 4 μm and 11 μm. The NOAA-9 satellite Advanced Very High Resolution Radiometer (AVHRR/2) is used as the data acquisition system. The satellite AVHRR system is described, as well as future TIROSN satellites. The pre-launch calibration of the radiometer is described in some detail. Post-launch calibration is examined using a reflectance difference method. The radiometer gains are shown to have changed by more than 20% from their pre-launch values. A LOWTRAN based atmospheric model suitable for New Zealand is developed to provide cloud free transmission values. Atmospheric scattering is shown to contribute negligibly to visible cloud measurements (for 8-bit radiometer resolution). The Channels 1 to 3 terrestrial reflectance is averaged from more than two years of satellite data. Sea-surface state is examined as a function of windspeed. A method of extracting surface temperature in rugged terrain is developed. Dual temperature measurements at 10.8 and 11.8 μm are used to estimate surface air temperature. The transfer of radiation in a single layer cloud is calculated as a function of cloud thickness, observation/illumination geometry and the effective radius of the cloud drop-distribution. The variation in drop-size is contained in an ensemble of modified-Gamma distributions whose effective radius varies from 1 to 30 μm with a fixed dispersion of 0.25. A technique is established which allows effective cloud radius to be estimated from 3.7 μm AVHRR/2 imagery. The radiation values at 0.65 μm and 11.8 μm are used to correct the 3.7 μm reflectance for variation in cloud thickness and temperature respectively. The procedure is limited to warm clouds of moderate optical depth. In addition, the inversion process generates values of cloud top height and temperature, cloud depth and column liquid water content. The method is used to observe the development of orographic cloud formed over the southern half of the North Island of New Zealand. The inversion results for this type of cloud are in agreement with aircraft measurements carried out by the New Zealand Meteorological Service and are well fitted by a simple drop-growth model.

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Yates, Jonathan Robert. "First principles calculation of nuclear magnetic resonance parameters." Thesis, University of Cambridge, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.428437.

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Asher, James. "Inclusion of dynamical effects in calculation of EPR parameters." Doctoral thesis, [S.l.] : [s.n.], 2006. http://deposit.ddb.de/cgi-bin/dokserv?idn=985600527.

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Manolatou, Christina. "Calculation of effective electromagnetic parameters of helix loaded composites." Thesis, Massachusetts Institute of Technology, 1995. http://hdl.handle.net/1721.1/36970.

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Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1995.
Includes bibliographical references (p. 101-104).
by Christina Manolatou.
M.S.

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Robinson, Michael J. "Finite element calculation of equivalent circuit parameters for induction motors." Thesis, Imperial College London, 1988. http://hdl.handle.net/10044/1/8003.

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McFarland, Robert Bynum 1964. "Calculation of transmission line parameters for multiconductor lines in a multi-dielectric medium." Thesis, The University of Arizona, 1992. http://hdl.handle.net/10150/278111.

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A method for computing the per-unit-length capacitance matrix and the inductance matrix for multiconductor transmission lines in a multi-dielectric medium is presented. The multi-dielectric medium consists of both planar and non-planar dielectric regions. The formulation is based on an integral equation method for the free charge distribution on conductor surfaces and the polarization charge distribution on the non-planar dielectric interfaces. The kernel of the integral equation is a space domain Green's function for a layered medium. The numerical solution is obtained by the method of moments.

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Simonis, Cinzia. "Parallel calculation and analysis of spine kinematic parameters using videofluoroscopy and image processing." Thesis, University of Southampton, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.261533.

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Yin, Yanan. "Calculation of frequency-dependent parameters of underground power cables with finite element method." Thesis, University of British Columbia, 1990. http://hdl.handle.net/2429/31119.

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In this thesis, the finite element method (FEM) is applied to the calculation of frequency-dependent series impedances and shunt capacitances of underground power cables. The principal equations describing the quasi-magnetic fields and static electric fields are solved with FEM based on the Galerkin technique. The Js method and the loss-energy method are derived to calculate the impedances of a multiconductor system from its field solution, and the energy method and the surface charge method are derived to calculate the capacitances. With a single-core (SC) coaxial cable, the suitability of quadratic isoparametric elements and high-order simplex elements are studied, and a suitable division scheme is suggested for the auto-mesh program. The conventional FEM with a field truncation boundary is applied to the impedance calculation of buried SC cables. Suitable locations for the field truncation boundary and division schemes in the earth are studied. The results show that rb ≥ 12[symbol omitted] is required to obtain accurate impedances of shallowly buried cables with the conventional FEM. This requires a large solution region in the earth at low frequencies. A new technique based on the perturbation concept is proposed to reduce the solution region in the earth. Comparisons between the results from the conventional FEM and from the proposed technique with a significantly reduced solution region in the earth show good agreement. In the case studies, the FEM is applied to the parameter calculation of multiphase SC cables, PT cables, sector-shaped cables, and stranded conductors. The numerical results are compared with those from analytical formulas.
Applied Science, Faculty of
Electrical and Computer Engineering, Department of
Graduate

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Chilà, Deborah. "Dose tracking in radiation oncology using daily CBCT: effects of physical parameters on dose calculation accuracy." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2020. http://amslaurea.unibo.it/20587/.

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The availability of cone beam computerized tomography (CBCT) images at the time of treatment has opened possibilities for recalculations and tracking of the delivered dose, becoming an effective tool for adaptive radiotherapy. A significant component in the accuracy of dose recalculation on CBCT images is the calibration of the Hounsfield units (HU) to density. The aim of this thesis, developed at the Policlinic of Modena, is to assert a methodology for the characterization of the HU-to-density calibration curve, and to evaluate the impact of the calibration phantom inserts composition and phantom volume on dose calculation accuracy. The HU-to-density calibration curves from four different phantoms were measured and compared. The HU output of a kV CBCT scan depends on the physical parameters of the phantom density inserts, with particular reference to the atomic number (Z), due to the photoelectric effect which is the main radiation-matter interaction at kV energies. The phantom radial diameter also influences the HU values on the image. The effect of scattering and beam hardening was examined as a function of phantom diameter, founding a high deviation on the HU value of the same density insert when varying the radial diameter of the phantom, especially for high densities. When we are dealing with CBCTs also the acquisition parameters influence the resulting image, that’s why we will show that a protocol-specific calibration curve is needed. The resulting calibration curves were used to compare the calculated doses against planned ones. The percent difference between recalculated and planned dose was obtained for chosen clinically important dose levels and a box plot analysis was conducted. Results show that the best calibration curve for dose recalculation on CBCT images has been obtained when a human-tissue-equivalent inserts are used and when the radial diameter of the phantom is close to the dimensions of the real patient.

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Radchenko, Taras, Valentyn Tatarenko, and Sergiy Bokoch. "Calculation of diffusivities in ordering f.c.c. alloy by the kinetic data about short- and long-range order parameters’ relaxation: Calculation of diffusivities in ordering f.c.c. alloy by the kineticdata about short- and long-range order parameters’ relaxation." Diffusion fundamentals 2 (2005) 57, S. 1-2, 2005. https://ul.qucosa.de/id/qucosa%3A14390.

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Dilan, Kavruk. "Calculation Of The Thermodynamic And Spectroscopic Quantities In Molecular Crystals Close To The Phase Transitons." Phd thesis, METU, 2011. http://etd.lib.metu.edu.tr/upload/12613037/index.pdf.

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We study in this thesis work the spectroscopic and thermodynamic quantities of some substances such as ammonium halides (NH4Cl, NH4I), ferroelectric crystals of tris-sarcosine calcium chloride (TSCC), tris-sarcosine calcium bromide (TSCB), organic compounds of carbon tetrachloride (CCl4) and s-triazine (C3N3H3) close to the phase transitions. Various physical and chemical properties of those materials have been measured near the critical points and have been reported in the literature. In this study, the spectroscopic parameters of the frequency shifts, intensity and bandwidths are calculated as functions of temperature or pressure near the phase transitions in ammonium halides using the experimental data from the literature. The spectroscopic parameters are related to the crystal volume and the specific heat in these compounds. The thermodynamic quantities of the specific heat, thermal expansion and the isothermal compressibility are also calculated in the solid and liquid phases of carbon tetrachloride using the experimental data. In another part of this thesis work, we analyze the temperature dependence of the spontaneous polarization and the dielectric susceptibility at fixed pressures for TSCC and TSCB by using the experimental data from the literature. The temperature dependence of the damping constant for the s-triazine is also calculated here close to the I-II transition. We use the theoretical models on the basis of the observations in the literature to calculate the critical behaviour of these physical quantities and we compare the results with the observed data. Various experimental studies in the literature give us the opportunity to find the proper way of fitting the calculated and observed results. This study gives us the chance of a better understanding of the critical behavior of the studied materials by verifying the values of some critical exponents and the types of transitions as expected by different theoretical models.

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Stack, Ian Malone. "Sensitivity of peak discharge calculation to GIS-derived hydrologic routing parameters in the TR-20 rainfall-runoff model." College Park, Md. : University of Maryland, 2006. http://hdl.handle.net/1903/3924.

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Thesis (M.S.) -- University of Maryland, College Park, 2006.
Thesis research directed by: Dept. of Civil and Environmental Engineering. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.

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Rahmani, Maryam. "On the calculation of time-domain impulse-response of systems from band-limited scattering-parameters using wavelet transform." Thesis, Mississippi State University, 2017. http://pqdtopen.proquest.com/#viewpdf?dispub=10270053.

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In the aspect of electric-ship grounding, the time-domain behavior of the ship hull is needed. The grounding scheme impacts the nature of voltage transients during switching events and faults, identifiability and locatability of ground faults, fault current levels, and power quality. Due to the large size of ships compared with the wavelengths of the desired signals, time-domain measurement or simulation is a time-consuming process. Therefore, it is preferred that the behavior be studied in the frequency-domain. In the frequency-domain one can break down the whole ship hull into small blocks and find the frequency behavior of each block (scattering parameters) in a short time and then con- nect these blocks and find the whole ship hull scattering parameters. Then these scattering parameters should be transferred to the time-domain. The problem with this process is that the measured frequency-domain data (or the simulated data) is band-limited so, while calculating time-domain solutions, due to missing DC and low frequency content the time-domain response encounters causality, passivity and time-delay problems. Despite availability of several software and simulation packets that convert frequency-domain information to time-domain, all are known to suffer from the above mentioned problems. This dissertation provides a solution for computing the Time-Domain Impulse-Response for a system by using its measured or simulated scattering parameters. In this regard, a novel wavelet computational approach is introduced.

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Foreman, Richard J. [Verfasser], Stefan [Akademischer Betreuer] Emeis, and Michael [Akademischer Betreuer] Kerschgens. "Improved calculation of offshore meteorological parameters for applications in wind energy / Richard J. Foreman. Gutachter: Stefan Emeis ; Michael Kerschgens." Köln : Universitäts- und Stadtbibliothek Köln, 2012. http://d-nb.info/1038227348/34.

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Negodaev, Igor. "The calculation of the thermal dependency of the magnetic susceptibility in extended systems with ab initio electronic structure parameters." Doctoral thesis, Universitat Rovira i Virgili, 2011. http://hdl.handle.net/10803/31934.

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La tesi estudia l'acoblament magnètic en sistemes de diferent dimensionalitat amb mètodes multireferencials. L’objectiu principal del treball és calcular propietats macroscòpiques, com la dependència de la susceptibilitat magnètica amb la temperatura, a partir de la constant d'intercanvi magnètic calculada, J. Aquest paràmetre microscòpic quantifica la interacció magnètica entre dos centres i es pot extreure per ajust de la corba de susceptibilitat experimental en sistemes finits però això no és possible en sistemes magnètics infinits com cadenes o capes 2D. L’estratègia del treball és calcular J en petits clusters i simular els sistemes estesos utilitzant aquesta J en l’Hamiltonià de Heisenberg en models de 8 a 16 centres. Amb l’espectre obtingut es construeixen les corbes de dependència tèrmica de la susceptibilitat magnètica que, comparades amb les experimentals, donen la possibilitat de quantificar les interaccions magnètiques dels materials estudiats a nivell microscòpic. S'han estudiat diferents tipus de sistemes estesos com cadenes i xarxes hexagonals, on els centres magnètics són ions de metalls de transició.
The thesis studies the magnetic coupling in systems of different dimensionality, by using multireference methods. The aim of the work is to determine macroscopic properties such as the thermal dependency of magnetic susceptibility, from the calculated magnetic exchange constant J. This microscopic parameter quantifies the magnetic interaction between two magnetic sites and can be extracted from the experimental susceptibility curve in finite systems. However this extraction is not possible in extended magnetic systems such as chains or 2D-layers. The strategy followed consists in calculating J in small clusters and in simulating the extended systems by introducing the calculated J in the Heisenberg Hamiltonian of 8 to 16 site models. From the spectrum, the thermal dependency of the magnetic susceptibility is the calculated. When compared to the experimental one, this curve gives a quantification of the magnetic interactions of the studied materials at the microscopic level. We have studied different types of extended systems such as chains and hexagonal lattices, where the magnetic sites are transition metal ions.

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Radchenko, Taras, Valentyn Tatarenko, and Sergiy Bokoch. "Calculation of diffusivities in ordering f.c.c. alloy by the kinetic data about short- and long-range order parameters’ relaxation." Universitätsbibliothek Leipzig, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-196109.

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Di, Chicco Augusto. "Optimization of a calculation scheme through the parametric study of effective nuclear cross sections and application to the estimate of neutronic parameters of the ASTRID fast nuclear reactor." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2018.

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This thesis presents the project for the optimization of the APOLLO3® neutronic calculation scheme applied to the 4th generation fast neutron reactor ASTRID. APOLLO3® is the new multipurpose neutronic platform developed by the CEA. It incorporates many of the previous generation codes used in the French reactor core design supply chain. Like all deterministic codes, APOLLO3® solves the neutron transport equation with a discretization of the variables of interest: multi-group method for the energy, discrete ordinates and spherical harmonics for the angular variable, collision probabilities and characteristics methods for the spatial variable. The resolution of the transport equation handles useful quantities such as the neutron flux and multiplication factor, fission rates and cross sections to understand the physical behaviour of the reactor core. Currently it is not possible to use deterministic codes to simulate an entire reactor with a heterogeneous 3D geometry and a fine energy description, so to simplify the study of complete neutron field at core level, the calculation scheme is divided into two phases: lattice and core calculation. The main purpose of this work is to find an optimal degree of approximations of the calculation scheme for the evaluation of a desired physical effect and of the user constraints. In order to reach this optimum, several studies have been carried out with different levels of approximations. The results have been benchmarked with the ones obtained using the stochastic code TRIPOLI4®, used as a reference and to ensure a good accuracy. Furthermore, several sensitivity studies have been carried out to understand how the different approximations affect the macroscopic cross sections evaluation, because these dependences are not yet fully understood.

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Hoshmeh, Abdullah, and Uwe Schmidt. "A Full Frequency-Dependent Cable Model for the Calculation of Fast Transients." Universitätsbibliothek Chemnitz, 2017. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-228649.

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The calculation of frequency-dependent cable parameters is essential for simulations of transient phenomena in electrical power systems. The simulation of transients is more complicated than the calculation of currents and voltages in the nominal frequency range. The model has to represent the frequency dependency and the wave propagation behavior of cable lines. The introduced model combines an improved subconductor method for the determination of the frequency-dependent parameters and a PI section wave propagation model. The subconductor method considers the skin and proximity effect in all conductors for frequency ranges up to few megahertz. The subconductor method method yields accurate results. The wave propagation part of the cable model is based on a cascaded PI section model. A modal transformation technique has been used for the calculation in the time domain. The frequency-dependent elements of the related modal transformation matrices have been fitted with rational functions. The frequency dependence of cable parameters has been reproduced using a vector fitting algorithm and has been implemented into an resistor-inductor-capacitor network (RLC network) for each PI section. The proposed full model has been validated with measured data.

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Huang, Ran. "Exact Thermodynamic Calculation of a Monatomic System and Its Ideal Glass Transition on a New Recursive Lattice Formed by Cubic Units." University of Akron / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=akron1239653703.

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Nekovář, Martin. "Výpočet a měření parametrů asynchronních motorů." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2012. http://www.nusl.cz/ntk/nusl-219752.

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The theme of this master´s thesis is calculation and measurement of the parameters of induction motor. The thesis is divided into several parts. The first and the second part describes the general construction and operating principle of asynchronous motors. The construction includes a description of each part of induction motor, which consists of stator and rotor. The thesis deals with three-phase symmetrical and asymmetric single-phase motors. Principle of operation with using the rotating magnetic field, which is circular at three-phase motors, single phase motors have field elliptical shape. The next part contains the motor replacement scheme. The fourth part contains the calculation of motor´s parameters through the formulas. In this part the procedures for obtaining parameters of the replacement scheme of induction motor are defined. The process of calculating the parameters of the motor replacement scheme of threephase asynchronous motor is created according to given documentation is the next part for the certain type. The next content of the thesis describe finite element method, simulation and measurement of asynchronous motors to get of parameters from no-load and short-circuit test. The comparison of the results from measurement, analytical calculation and from simulation is given in the last chapter.

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Michniak, Radomír. "Možnosti využití rozptýlené výztuže pro konstrukční betony." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2013. http://www.nusl.cz/ntk/nusl-226092.

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The master's thesis is focused on polypropylene fibres, their properties, availability, pitfalls associated with the use in practice. In the experimental part are the results of testing specimens with dispersed reinforcement fibers in varying proportions and their comparison.

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Alexandra, Markovic Markovic, and Edforss Arvid. "An evaluation of current calculations for safety stock levels." Thesis, Tekniska Högskolan, Högskolan i Jönköping, JTH, Maskinteknik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-36505.

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Guthmann, Thomas, and Frank Engelmann. "Optimierung von Druckbehältern unterschiedlicher Geometrien und Werkstoffe." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-215171.

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Einleitung Moderne Simulations- und Berechnungsmethoden, wie beispielsweise die Finite-Elemente-Methode (FEM), erlauben dem Konstrukteur bereits in einer relativ frühen Phase des Entwicklungsprozesses die wesentlichen Eigenschaften des Produktes virtuell am Computer zu analysieren. Die Ergebnisse dieser Berechnungen können anschließend zur zielgerichteten Verbesserung ausgewählter Produkteigenschaften genutzt werden. Der Aufwand für die Optimierung ist dabei in erster Linie von der Komplexität des Produktes abhängig. Produkte, bei welchen die mathematischen Zusammenhänge zwischen den Ein- und Ausgangsparametern bekannt ist, lassen sich oftmals recht einfach analytisch optimieren. Bei komplexen Produkten oder einer großen Anzahl an Einflussparametern lassen sich diese Zusammenhänge in vielen Fällen nicht herleiten, so dass die Optimierung bisher meist nach dem Trial and Error-Verfahren erfolgte. Diese heuristische Vorgehensweise führt durch eine hohe Anzahl an notwendigen Iterationsschleifen zu einem extremen Anstieg der Zeit und der Kosten, wobei die Wiederholungsrate des Entwicklungsprozessschrittes in hohem Maße von der Erfahrung und dem vorhandenen Wissen des Konstrukteurs abhängig ist. Der Einsatz von wissenschaftlichen Optimierungsverfahren, wie beispielsweise der Topologieoptimierung, ermöglicht eine zielgerichtete und weitestgehend automatisierbare Optimierung von komplexen Produkten. Die hohe Komplexität des Produktes ist dabei oftmals nicht auf den ersten Blick ersichtlich. Beispielsweise gestaltet sich die Gewichtsoptimierung von Druckbehältern mit nicht rotationsymmetrischen Querschnitten aufgrund der komplexen Spannungsverläufe schwierig. Grundsätzlich wird bei Leichtbaukonstruktionen versucht, die zur Verfügung stehende Werkstofffestigkeit in den gegebenen Sicherheitsgrenzen voll auszuschöpfen. Hierfür ist es notwendig, die Materialverteilung an dem Kraftverlauf anzupassen. Bei einem mehrachsigen Spannungszustand, wie er bei den Druckbehältern mit komplexen Geometrien vorliegt, bestehen zwischen der Materialverteilung und den Spannungsverläufen über die Geometrie komplexe Zusammenhänge, so dass für die optimale Materialverteilung keine allgemeingültige triviale Lösung existiert.

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Moloko, Lesego Ernest. "Impact of beryllium reflector ageing on Safari–1 reactor core parameters / L.E. Moloko." Thesis, North-West University, 2011. http://hdl.handle.net/10394/6930.

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The build–up of 6Li and 3He, that is, the strong thermal neutron absorbers or the so called "neutron poisons", in the beryllium reflector changes the physical characteristics of the reactor, such as reactivity, neutron spectra, neutron flux level, power distribution, etc.; furthermore,gaseous isotopes such as 3H and 4He induce swelling and embrittlement of the reflector. The SAFARI–1 research reactor, operated by Necsa at Pelindaba in South Africa, uses a beryllium reflector on three sides of the core, consisting of 19 beryllium reflector elements in total. This MTR went critical in 1965, and the original beryllium reflectors are still used. The individual neutron irradiation history of each beryllium reflector element, as well as the impact of beryllium poisoning on reactor parameters, were never well known nor investigated before. Furthermore, in the OSCAR{3 code system used in predictive neutronic calculations for SAFARI–1, beryllium reflector burn–up is not accounted for; OSCAR models the beryllium reflector as a non–burnable, 100% pure material. As a result, the poisoning phenomenon is not accounted for. Furthermore, the criteria and hence the optimum replacement time of the reflector has never been developed. This study presents detailed calculations, using MCNP, FISPACT and the OSCAR{3 code system, to quantify the influence of impurities that were originally present in the fresh beryllium reflector, the beryllium reflector poisoning phenomenon, and further goes on to propose the reflector's replacement criteria based on the calculated fluence and predicted swelling. Comparisons to experimental low power flux measurements and effects of safety parameters are also established. The study concludes that, to improve the accuracy and reliability of the predictive OSCAR code calculations, beryllium re flector burn–up should undoubtedly be incorporated in the next releases of OSCAR. Based on this study, the inclusion of the beryllium reflector burn–up chains is planned for implementation in the currently tested OSCAR–4 code system. In addition to beryllium reflector poisoning, the replacement criteria of the reflector is developed. It is however crucial that experimental measurements on the contents of 3H and 4He be conducted and thus swelling of the reflector be quantifed. In this way the calculated results could be verified and a sound replacement criteria be developed. In the absence of experimental measurements on the beryllium reflector, the analysis and quantifcation of the calculated results is reserved for future studies.
Thesis (M.Sc. Engineering Sciences (Nuclear Engineering))--North-West University, Potchefstroom Campus, 2011.

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Nagurnas, Saulius. "Stabdomų lengvųjų automobilių judėjimo parametrų tyrimas." Doctoral thesis, Lithuanian Academic Libraries Network (LABT), 2005. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2005~D_20050623_122944-88180.

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Sláma, Pavel. "Návrh měřicího pracoviště v LabView pro účely měření spektra a světelného toku." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2017. http://www.nusl.cz/ntk/nusl-316920.

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This thesis deals with luminance parameters measurement and ways to accomplish this using LabView software. The first part focuses on luminance parameters measurable by spectroradiometer and their meaning. Following part introduces reader to hardware equipment that is used in the measurement. Third part contains description of LabView software and explains what is required to make a communication between equipment and PC work. Next part explains how the communication with peripherals was achieved. Following up is the part where it is described how programs controlling AC and DC power supplies work. In this part the user interface is described.

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Lövgren, Robin. "Four-component DFT calculations of phosphorescence parameters." Thesis, Linköping University, Computational Physics, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-19180.

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Oscillator strengths and transition energies are calculated for several mono-substitutes of benzene and naphthalene molecules. The substituents investigated are chlorine, bromine and iodine. Calculations for these molecules are presented, at the Hartree-Fock and DFT level of theory. The functional used in DFT is CAM-B3LYP.

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Lynch, Charlotte Isabella. "First-principles calculations of NMR parameters for materials applications." Thesis, University of Oxford, 2017. https://ora.ox.ac.uk/objects/uuid:f44b9122-1826-410e-990d-a88dc3bb1432.

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Nuclear magnetic resonance (NMR) is a powerful experimental technique for probing the local environment of nuclei in materials. However, it can be difficult to separate the large number of interactions that are recorded in the resulting spectra. First-principles calculations based on quantum mechanics therefore provide much-needed support for interpreting experimental spectra. In this way, the underlying mechanisms recorded in experimental spectra can be investigated on an atomic level, and trends can be noted with which to guide the direction of future experiments. This thesis presents two cases in which first-principles calculations do just that. The first is an investigation of the perovskite structures of NaNbO₃, KNbO₃, LiNbO₃ and the related solid solutions of Na_xK_1-xNbO₃, K_xNa_1-xNbO₃ and Li_xNa_1-xNbO₃ in order to study how structural disorder affects their NMR parameters. The second investigation involves the calculation of the Knight shift in platinum, palladium and rhodium---in their elemental bulk forms and in a set of surface structures. The Knight shift is a systematic shift in the NMR frequencies of metallic systems. It arises from the hyperfine interaction between the nuclear spins and the spins of the unpaired conduction electrons. When calculating the Knight shift, it is found that the Brillouin zone must be very finely sampled. A discussion of core polarisation is also presented. This is the polarisation of core electrons as a result of their interaction with valence electrons. In the case of Curie paramagnets, core polarisation can have a significant effect on the calculation of hyperfine parameters.

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Gonçalves, João Nuno Santos. "Calculations of electronic structure and hyperfine parameters in oxides." Master's thesis, Universidade de Aveiro, 2007. http://hdl.handle.net/10773/2567.

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Mestrado em Engenharia Física
Cálculos de primeiros princípios de estrutura electrónica são efectuados em óxidos de manganês LaMnO3 e CaMnO3 para obter gradientes de campo eléctrico hiperfinos. Os resultados dos cálculos são comparados com resultados experimentais e de outros cálculos de primeiros princípios. Uma descrição das interacções hiperfinas é seguida de uma introdução ao gradiente de campo eléctrico e ao método de espectroscopia de perturbações de correlação angular, descrevendo detalhes experimentais. De seguida uma descrição geral de manganites de terras raras com estrutura do tipo perovskite é apresentada, com ênfase em LaMnO3 e aspectos estruturais. A base teórica do método computacional aplicado nestes materiais é também apresentada para melhor compreensão dos resultados obtidos. Dos resultados e da discussão concluímos que é possível obter valores de campo eléctrico com uma precisão aceitável quando comparado com os cálculos de primeiros princípios para o LaMnO3, e para o CaMnO3 é certamente possível melhorar os resultados. Os resultados obtidos seguem a variação esperada para o CaMnO3, pelo menos qualitativamente. ABSTRACT: First principles calculations of electronic structure are done on perovskite manganese based oxides LaMnO3 and CaMnO3 to obtain the hyperfine electric field gradients. The calculated results are compared with experimental and other first-principles results. A description of hyperfine interactions is followed by an introduction to the electric field gradient and the perturbed angular correlation spectroscopy, explaining experimental details of this method. Next, a general description of rare earth perovskite type manganites, is presented, with emphasis on LaMnO3 and structural aspects. The theoretical basis of the computational method applied on these materials is also presented for better understanding of the results obtained. These results finish with a discussion and a conclusion. From the results and discussion we conclude that the values of the electric field gradient can be calculated with acceptable precision when compared with other first principles results on LaMnO3, and for CaMnO3 it is certainly possible to improve the results. The qualitative results obtained for CaMnO3, however, follow the expected variation.

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Hägg, Jakob, and Niclas Hector. "Det kan väl inte vara så mycket miljöpåverkan i ett logistikflöde? : Att konstruera en beräkningsmodell för miljöpåverkan i interna logistikflöden på ett fallföretag inom fordonsindustrin." Thesis, Linnéuniversitetet, Institutionen för ekonomistyrning och logistik (ELO), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-53174.

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Background: One of the biggest threat of our time is the environmental impact caused by humans, for example thru emissions of greenhouse gases. The manufacturing industry, of which the automotive industry is a part, stands for a big part of these emissions, and today companies have to face big challenges regarding measuring and reducing of their carbon footprint. To work in a successful way with the environmental impact of a manufacturing industry, process mapping and identification of environmental parameters need to be done. Purpose: The purpose of this study is to do a situation analysis by identify what parameters in a logistic flew between the activities unloading goods and assembly at Scania Oskarshamn. Furthermore, the report supposed to create and develop a model for calculation of the environmental impact of a logistic flew based on environmental parameters. Methodology: This report is a case study that have been performed at the Scania site in Oskarshamn. The report aim to create and develop a calculation model for calculation of the environmental impact of a logistic flew. Empirical material has been collected thru both interviews and by searching in Scania ́s own database. In order to create the model, a situation analysis was made by performing a process map and then environmental parameters was identified. Employers at Scania tested the calculation model, which is the result of this study, in order to secure the function of the model. Conclusions: A specific flew of goods between the activities unloading goods and assembly was identified and several environmental parameters was detected and grouped in the three categories; energy use, resource consumptions and waste. Calculations are performed in CO2 equivalents according to the global warming potential named by UN in the Kyoto protocol. This in order to enable comparisons between the different environmental parameters. The model is performed as an Excel model because this is the program that the company use for this types of calculations, and according to the author Excel is a program suitable for the kind of model making performed in this study.
Bakgrund: Ett av vår tids största hot är den miljöpåverkan som människan ger upphov till, bland annat genom utsläpp av växthusgaser i form av koldioxid. Den industriella industrin, av vilken fordonsindustrin är en del, står för en stor andel av dessa och enorma utmaningar ställs idag på företag att kunna mäta och reducera de klimatavtryck som verksamhet gör. För att på ett framgångsrikt sätt kunna arbeta med en verksamhets klimatavtryck behöver en kartläggning av dess processer och identifierande av miljöpåverkande parametrar göras. Syfte: Rapportens syfte är att utifrån en nulägesbeskrivning identifiera miljöpåverkande parametrar i logistikflödet mellan lossning och monteringslinorna i monteringsverkstaden hos Scania i Oskarshamn. Vidare ämnar rapporten att presentera en beräkningsmodell för miljöpåverkan i det utvalda logistikflödet hos Scania i Oskarshamn, med relevanta nyckeltal som baserats på identifierade miljöpåverkande parametrar. Genomförande: Denna rapport är en fallstudie som genomförts på Scanias avdelning för hyttillverkning i Oskarshamn. Målet med arbetet har varit att konstruera en modell för beräkning av den miljöpåverkan som ett logistikflöde ger upphov till. Empiriskt material har inhämtats både genom intervjuer och data sökning i Scanias egna databaser avseende emballage. För att kunna konstruera en modell har en processkartläggning genomförts, sedan miljöpåverkande parametrar identifierats för att till sist möjliggjort utvecklandet av en modell för miljöberäkning. Denna modell har sedan testats på en pilotgrupp bestående av anställda på fallföretaget samt andra examensarbetare som genomfört andra fallstudier på företaget. Slutsats: Ett specifikt flöde mellan lossning av gods och montering har identifierats och avgränsats i studien där ett flertal miljöpåverkande parametrar identifierats i studerat logistikflöde och dessa har delats in i tre grundtyper: Energiutnyttjande, resursförbrukning och avfall. Miljöberäkningar genomförs i CO2-ekvivalenter i enlighet med FN:s global warming potential för att möjliggöra jämförelser mellan de olika miljöpåverkande parametrarna. Modellen presenteras i Excell-format då detta dels är det verktyg som fallföretaget anser är det mest använda men också för att programmet i sig lämpar sig utmärkt för den typ av modellbyggande som förekommit i detta arbete.

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31

Parker, Karen Elizabeth. "Calculating ion exchange parameters from pure clay assemblages." Thesis, University of Birmingham, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.422780.

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Mackie, Ross Alexander. "Calculations and Measurements of Positron Annihilation Parameters in Perovskite Oxides." Thesis, University of Dundee, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.521695.

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Munzarová, Markéta. "Quantum chemical calculations of EPR parameters for transition metal complexes." [S.l. : s.n.], 2001. http://www.bsz-bw.de/cgi-bin/xvms.cgi?SWB9587938.

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Maštera, Lukáš. "Koncepce vysokorychlostní vrtné hlavy pro odběr vzorků hornin." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2021. http://www.nusl.cz/ntk/nusl-443237.

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THE THESIS FOCUSES ON A CONSTRUCTION DESIGN OF A NEW DRILLING HEAD DESIGNED TO REPLACE THE ORIGINAL ONE IN A MULTIDRILL HYNDAGA DRILLING RING. THE SUBSTITUTION IS SUPPOSED TO PROVIDE A SOLUTION TO THE SHORTCOMINGS OF THE CURRENTLY USED DRILLING HEAD. THE THESIS ANALYSES PARAMETERS OBTAINED FROM THE MANUFACTURER, NEW PRODUCTION REQUIREMENTS AND PROPOSES TWO TYPES OF MOTORS INNOVATIVE METHODS HAD BEEN IMPLEMENTED IN CALCULATIONS OF CONCEPTUAL PARAMETERS OF THE NECESSARY COMPONENTS. THE OUTCOME IS A NEW F-TYPE DRILLING HEAD.

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35

Escarela, Perez Rafael. "Finite-element determination of two-axis transient parameters for the simulation of turbine-generators." Thesis, Imperial College London, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.243518.

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36

Clarkson, Sean Alan. "The use of consumer depth cameras for calculating body segment parameters." Thesis, Sheffield Hallam University, 2015. http://shura.shu.ac.uk/20644/.

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Body segment parameters (BSPs) are pivotal to a number of key analyses within sports and healthcare. Accuracy is paramount, as investigations have shown small errors in BSPs to have significant impact upon subsequent analyses, particularly when analysing the dynamics of high acceleration movements. There are many techniques with which to estimate BSPs, however, the majority are complex, time consuming, and make large assumptions about the underlying structure of the human body, leading to considerable errors. Interest is increasingly turning towards obtaining person-specific BSPs from 3D scans, however, the majority of current scanning systems are expensive, complex, require skilled operators, and require lengthy post processing of the captured data. The purpose of this study was to develop a low cost 3D scanning system capable of estimating accurate and reliable person-specific segmental volume, forming a fundamental first step towards calculation of the full range of BSPs. A low cost 3D scanning system was developed, comprising four Microsoft Kinect RGB-D sensors, and capable of estimating person-specific segmental volume in a scanning operation taking less than one second. Individual sensors were calibrated prior to first use, overcoming inherent distortion of the 3D data. Scans from each of the sensors were aligned with one another via an initial extrinsic calibration process, producing 360° colour rendered 3D scans. A scanning protocol was developed, designed to limit movement due to postural sway and breathing throughout the scanning operation. Scans were post processed to remove discontinuities at edges, and parameters of interest calculated using a combination of manual digitisation and automated algorithms. The scanning system was validated using a series of geometric objects representative of human body segments, showing high reliability and systematic over estimation of scan-derived measurements. Scan-derived volumes of living human participants were also compared to those calculated using a typical geometric BSP model. Results showed close agreement, however, absolute differences could not be quantified owing to the lack of gold standard data. The study suggests the scanning system would be well received by practitioners, offering many advantages over current techniques. However, future work is required to further characterise the scanning system's absolute accuracy.

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Day, Stephen Paul. "Approaches to ab-initio GIPAW-DFT calculations of NMR parameters in disordered materials." Thesis, University of Warwick, 2015. http://wrap.warwick.ac.uk/78781/.

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The use of ab initio Density Functional Theory (DFT) to calculate key Nuclear Magnetic Resonance (NMR) parameters has been shown to be very successful in a variety of cases. These calculations allow one to extract meaningful data from NMR measurements by providing a foundation for spectral peak assignment. However, first principle calculations for disordered systems, typically based on a single realisation of the disorder, are inadequate if the NMR parameters depend sensitively on the location of the disordered species. In this thesis, a number of different approaches for characterising disorder in solids are presented. The aim of which is to overcome current challenges regarding the computational cost of conventional supercell approaches that make it difficult to perform a direct study of the complete configurational ensemble for any supercell with a sufficient simulation cell. A case study is presented for the Ge-based apatite La7.5Ca2.5Ge6O25.75 that shows that the number of configurations one needs to consider can be vastly reduced by exploiting the symmetry of the system over a wholly enumerative approach, although exhaustive statistical averaging of the atomic positions required to reproduce the atomic resolution afforded by the solid-state NMR (ssNMR) measurement makes this problem intractable via this methodology. The sodium potassium niobate system (NaxK1-xNbO3) is studied across a series of compositions between the ordered KNbO3 and NaNbO3 end-members. This novel material exhibits purely atomic position / permutation disorder that is reflected in initial 23Na and 93Nb MAS NMR studies, but the true explanation of the disorder described by this data is not well understood. The Special Quasi-random Structure (SQS) approach to studying this disorder is presented as a computationally cheaper alternative to the supercell approach. It is noted that further studies are required to assess whether this is an adequate description of the NaxK1-xNbO3 system due the complications of modelling the complex tilting patterns exhibited by these structures. A combined ssNMR and GIPAW-DFT approach is reported to resolve the complex disorder within the vaterite polymorph of calcium carbonate. The computational data for the various structural candidates in the literature is utilised to simulate the highly sensitive DOR data, thereby elevating the predictive capability of this complementary approach to substantiate the stacking model of vaterite that views the material as a dynamic system under ambient conditions.

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38

Gold, Erica Ashley. "Calculating likelihood ratios for forensic speaker comparisons using phonetic and linguistic parameters." Thesis, University of York, 2014. http://etheses.whiterose.ac.uk/6166/.

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The research presented in this thesis examines the calculation of numerical likelihood ratios using phonetic and linguistic parameters derived from a corpus of recordings of speakers of Southern Standard British English. The research serves as an investigation into the development of the numerical likelihood ratio as a medium for framing forensic speaker comparison conclusions. The thesis begins by investigating which parameters are claimed to be the most useful speaker discriminants according to expert opinion, and in turn examines four of these ‘selected/valued’ parameters individually in relation to intra- and inter-speaker variation, their capacities as speaker discriminants, and the potential strength of evidence they yield. The four parameters analyzed are articulation rate, fundamental frequency, long-term formant distributions, and the incidence of clicks (velaric ingressive plosives). The final portion of the thesis considers the combination of the four parameters under a numerical likelihood ratio framework in order to provide an overall likelihood ratio. The contributions of this research are threefold. Firstly, the thesis presents for the first time a comprehensive survey of current forensic speaker comparison practices around the world. Secondly, it expands the phonetic literature by providing acoustic and auditory analysis, as well as population statistics, for four phonetic and linguistic parameters that survey participants have identified as effective speaker discriminants. And thirdly, it contributes to the forensic speech science and likelihood ratios for forensics literature by considering what steps can be taken to conceptually align the area of forensic speaker comparison with more developed areas of forensic science (e.g. DNA) by creating a human-based (auditory and acoustic-phonetic) forensic speaker comparison system.

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Haška, Miroslav. "Přepočet kotle při změně jmenovitých parametrů." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2009. http://www.nusl.cz/ntk/nusl-228707.

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This thesis concerns with recalculation of steam boiler. Arrangement for reaching of new steam boiler parameters and temperature of combustion gases was suggested at first. Then it was verified with thermal calculation, all necessities included.

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40

Argyn, Aidar. "Material And Heat Balance Calculations Of Eti-bakir Plant By Computer." Master's thesis, METU, 2008. http://etd.lib.metu.edu.tr/upload/2/12609734/index.pdf.

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In this study the data taken from Outokumpu type Flash smelter of Eti-Bakir Plant (Samsun, Turkey) was used to write a computer program in Visual Basic with interface to Excel. Flash smelting is the pyrometallurgical process for smelting metal sulfide concentrates, used in Eti-Bakir plant. In this plant, copper flash smelting consists of blowing fine, dried copper sulfide concentrate mixtures, silica flux, lignite with air into the furnace and natural gas as main fuel. The molten matte is the principal product of the furnace and slag contains 0.5-2% Cu. It is sent to a slag treatment (flotation) process for Cu recovery. This flash furnace off-gas contains from 8-12 volume % SO2 which is fixed as H2SO4. Written program was used to optimize the consumption of oxygen enriched air, fuel and lignite in this Flash Smelter by making material and heat balance of the plant.

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41

Nguyen, Thui Thuong. "First-principles calculations of solid-state transition metal NMR parameters in functional inorganic materials." Thesis, Rennes 1, 2015. http://www.theses.fr/2015REN1S115/document.

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Ce manuscrit de thèse est dédié aux calculs quantiques de paramètres de spectroscopie de résonance magnétique nucléaire (RMN) de métaux de transition dans des composés inorganiques de l’état solide. Le manuscrit est divisé en cinq parties. La première partie présente les atouts de la spectroscopie RMN en tant que technique d’investigation de composés inorganiques de l’état solide. Dès lors que le noyau sondé est un métal de transition, l’expérience doit être complétée par des calculs quantiques afin d’interpréter au mieux les données expérimentales. La seconde partie du manuscrit est dédiée à la description de la RMN et des outils méthodologiques utilisés dans ce travail. Le troisième chapitre est dédié au calcul du déplacement chimique de l’isotope 95 du molybdène dans des clusters halogénés de formule [Mo6X14]2- (X = Cl, Br, I). Une attention particulière est donnée à l’influence des effets de solvatation sur le calcul. Le quatrième chapitre est dédié à l’étude des composés A6Re3Mo3S8(CN)5 (A = K, Cs) dont la structure cristallographique est basée sur un motif octaédrique hétéronucléaire Re3Mo3S8(CN)6. La résolution structurale par diffraction des rayons X sur monocristal n’ayant pas permis de résoudre le problème de la distribution des métaux de transition dans l’octaèdre, une étude spectroscopique in silico sur la base de calculs DFT moléculaires et périodiques a été entreprise. Dans le dernier chapitre, des composés hétéronucléaires de formule [Ln6-6xLn6xO(OH)8(NO3)6(H2O)12]2+ (Ln = Pr-Lu, Y) ont été étudiés du point de vue théorique afin de mieux comprendre les données spectroscopiques collectées
This work is devoted to the calculations of nuclear magnetic resonance (NMR) parameters of transition metal nuclei in inorganic solid-state materials using first-principles calculations. The manuscript is divided in five chapters. The first one shows that NMR is an interesting spectroscopic method to gain some information on the properties of inorganic materials. As far as the probed nucleus is a transition metal, experiments must be completed with quantum chemical calculations in order to better interpret the spectroscopic data. The second chapter is devoted to the quantum chemical tools that are necessary to the understanding of this work are presented. The third chapter deals with the computations of 95Mo NMR parameters of [Mo6X14]2- (X = Cl, Br, I) octahedral clusters. A special attention is paid to the influence of solvation effects on the computed NMR parameters. The fourth chapter is devoted to the study of A6Re3Mo3S8(CN)5 (A = K, Cs) compounds. Their crystal structures are based on a heteronuclear octahedral motif Re3Mo3S8(CN)6. Since X-ray diffraction refinements did not solve the colouring problem in the octahedron, an in silico spectroscopic study has been carried out using molecular and periodic DFT calculations. The last chapter of this report deals with heteronuclear polyoxolanthanides that have been studied using first-principles calculations in order to better understand their 89Y NMR spectra

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42

David, Dugdale. "Electronic structure calculations on nitride semiconductors and their alloys." Thesis, Durham University, 2000. http://etheses.dur.ac.uk/4324/.

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Calculations of the electronic properties of AIN, GaN, InN and their alloys are presented. Initial calculations are performed using the first principles pseudopotenial method to obtain accurate lattice constants. Further calculations then investigate bonding in the nitrides through population analysis and density of state calculations, the empirical pseudopotential method is also used in this work. Pseudopotentials 'or each of the nitrides are constructed using a functional form that allows strained material and alloys to be studied. The conventional k,p valence band parameters for both zincblende and wurtzite are obtained from the empirical band structure using two different methods. A Monte-Carlo fitting of the k.p band structure to the pseudopotential data (or an effective mass method for the zincblende structure) is used to produce one set. Another set is obtained directly from the momentum matrix elements and energy eigenvalues at the centre of the Brillouin zone. Both methods of calculating k.p parameters produce band structure in excellent agreement with the original empirical band calculations near the centre of the Brillouin zone. The advantage of the direct method is that it produces consistent sets of parameters, and can be used in studies involving a series of alloy compositions. Further empirical pseudopotential method calculations are then performed for alloys of the nitrides. In particular, the variation of the band gap with alloy composition is investigated, and good agreement with theory and experiment is found. The direct method is used to obtain k.p parameters for the alloys, and is contrasted with the fitting approach. The behaviour of the nitrides under strain is also studied. In particular, valence band offsets for nitride heterojunctions are calculated, and a strong forward-backward asymmetry in the band offset is found, in good agreement with other results in the literature.

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43

Biswal, Mamata. "Determination and first principles calculations, using the PAW/GIPAW method, of NMR parameters in inorganic fluorides." Phd thesis, Université du Maine, 2013. http://tel.archives-ouvertes.fr/tel-01015856.

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This thesis focuses on the determination and the modeling, by the PAW/GIPAW (Gauge Including Projector Augmented Waves) method, of NMR parameters in inorganic fluorides. In the first part, a correlation between experimental 19F isotropic chemical shift (diso) and calculated 19F isotropic shieldings (siso) of binary fluorides with obvious assignments is established that allows to predict 19F NMR spectra with a good accuracy. The quadrupolar parameters of these fluorides are also determined and calculated. In the second part, a complete and unambiguous assignment of the 19F NMR lines of NbF5 and TaF5 is obtained, ensured by the linearity between experimental 19F diso values and calculated 19F siso values. On the other hand, for the studied MF4 (b-ZrF4, HfF4, CeF4, ThF4) compounds, characterized by smaller 19F diso ranges, except for ThF4, the poor correlations between experimental 19F diso and calculated 19F siso values prevent us to propose an assignment of the 19F NMR lines. In the last part, NaAsF6 and KPF6, exhibiting large 19F-X 1J-coupling and phase transitions at temperatures close to room temperature (RT) are investigated by DTA or DSC and variable temperature X-ray powder diffraction and multinuclear solid-state NMR. The structures of a- and b-NaAsF6 are determined. KPF6 adopts a disordered high symmetry structure at RT. Unfortunately, attempts to determine the atomic positions of the two first low temperature phases remain unsuccessful. This work highlights the potentialities and some limitations of this method as well as the care that must be taken when dealing with optimized structures.

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Storoni, Laurent Charles. "Lattice gauge actions : non-perturbative simulations of heavy hybrid states and perturbative calculations of lattice parameters." Thesis, University of Cambridge, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.620252.

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Mejuto, Carlos. "Improved lumped parameter thermal modelling of synchronous generators." Thesis, University of Edinburgh, 2010. http://hdl.handle.net/1842/4612.

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Within the existing available mix of numerical and analytical thermal analysis options, lumped parameter thermal modelling is selected as the operational backbone to develop an improved novel synchronous generator thermal modelling package. The objective is for the creation of a user friendly quick feedback tool, which can serve as a means to make quick machine design thermal calculations and answer customer queries quickly and reliably. Furthermore, thermally improved generator designs will allow for inevitable operational losses to be channelled away from the machine more efficiently. As a result, machine component temperatures will be reduced, allowing lower generator thermal ratings. The end result will be smaller, longer lasting, more efficient generators, with the ability to be adapted with greater ease to particular applications. With the contribution of selected numerical analysis techniques, mainly finite element analysis for the distribution of iron losses, the MySolver thermal modelling package is developed and presented in this thesis. It is this combination of numerical and analytical tools that improves synchronous generator thermal modelling accuracy, but ultimately it is the lumped parameter nature of the thermal models developed that makes MySolver succeed as a reliable quick feedback electrical machine thermal design tool, validated using experimental results for a wide range of operating conditions. The initial part of the thesis analyses the electrical machine thermal modelling techniques available today, indicating advantages and disadvantages associated with each one, and providing a rationale for the selection of lumped parameter modelling to be used by MySolver. The development of the synchronous generator lumped parameter thermal models is detailed, with examples on its construction presented. Subsequently, finite element analysis is utilised to predict the distribution of machine iron losses across the rotor and stator laminations, with the findings applied to MySolver. Furthermore, a study is performed into the lumped parameter discretisation level needed to effectively represent machine windings. MySolver is experimentally verified using experimental data from a fully instrumented synchronous generator and this data is also used to obtain further insight into the temperature distribution within the generator. In the final part results are evaluated and the use of MySolver for modelling and optimising electrical machines is discussed. Finally, appropriate conclusions on the work presented are drawn.

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Henrysson, Magdalena. "Calculating zeros of analytic functions with MatLab." Thesis, Växjö University, School of Mathematics and Systems Engineering, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:vxu:diva-2027.

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Betrakta en analytisk funktion f som beror av en komplex variabel z och ett ändligt antal reella parametrar param1, param2, ..., paramk, där k är ett positivt heltal. Rötterna till funktionen, med avseende på variabeln z, erhålls genom att lösa ekvationen f(z, param1, param2, ..., paramk)=0. Således kommer dessa rötter att vara beroende av parametrarna. Låt en av parametrarna paramj, där j är ett positivt heltal mindre än eller lika med k, vara monotont ökande eller avtagande på ett reellt intervall. Även funktionens rötter kommer att variera, till följd av de olika värdena på parametern paramj.

Ett datorprogram, som beräknar och undersöker rörelsen hos rötterna till en funktion då en parameter varierar, har utvecklats och implementerats i MatLab. Underprogram som använder numerisk analys i form av sekantmetoden för att beräkna approximationer av rötter och linear algebra för att kunna identifiera de rötter som är felaktiga, har också skrivits. Det vill säga, programmets huvudsakliga åtgärder ligger i att kontrollera om de beräknade värdena är korrekta och att rätta till de som är felaktiga.

Examensuppgiften och det implementerade programmet har främst varit inriktade på ljuddämpare, vilket innebär en problemställning, där rötterna till en funktion undersöks för att analysera hur akustiska vågor fortplantas vid olika villkor. Således har den huvudsakliga målsättningen varit att förenkla tillvägagångssättet för att beräkna rötter.

Consider an analytic function f of a complex variable z and of a finite number of real parameters param1, param1, ..., paramk, for a positive integer k. The roots of the function, with respect to the variable z, are obtained by solving the equation f(z, param1, param2, ..., paramk)=0. Consequently those roots will depend on the parameters. Let one of the parameters paramj, where j is a positive integer less or equal to k, be monotonically increasing or decreasing on an interval of the real line. As a consequence of those different values of paramj, also the roots of the function f will vary.

A computer program that calculates and examines the behavior of the roots of a function as one parameter varies, has been developed and implemented in MatLab. Subroutines have been written, which use numerical analysis by using the secant method to calculate approximations of roots and linear algebra to identify the false roots. That is, the main measures of this program is to make sure that the calculated values are correct and to adjust the false ones.

The paper and the implemented program are principally concentrated on silencers, that is, on modal analysis. Modal analysis is the examination of how the shape and the behaviour of acoustic waves are affected by different conditions, which is done by studying the roots of a function. Consequently, the main purpose has been to facilitate the procedure of finding roots.

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Sterner, Jay. "SMARTPHONE-TAPE METHOD FOR CALCULATING BODY SEGMENT INERTIAL PARAMETERS FOR ANALYSIS OF PITCHING ARM KINETICS." DigitalCommons@CalPoly, 2020. https://digitalcommons.calpoly.edu/theses/2133.

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The objectives of this study were to (1) develop a non-invasive method (referred to as Smart Photo-Tape) to calculate participant-specific upper arm, forearm, and hand segment inertial properties (SIPs) (e.g. mass, center of mass, and radii of gyration) and (2) use those Smart Photo-Tape properties in inverse dynamics (ID) analyses to calculate injury-related pitching arm kinetics. Five 20- to 23- year-old baseball pitchers were photographed holding a baseball and analyzed using the Smart Photo-Tape method to obtain 3-D inertial properties for their upper arm, forearm, and hand. The upper arm and forearm segments were modelled as stacked elliptic cylinders and the hand was modelled as an ellipsoid. One participant received a dual energy x-ray absorptiometry (DXA) scan and conducted a motion analysis study, pitching 10 fastballs. Scaled SIPs from cadaver studies and Smart Photo-Tape SIPs were compared using one sample t-tests. Pitching arm kinetic predictions were calculated and compared using scaled inverse dynamics (ID), Smart Hand ID (a combination of scaled SIPs for the upper arm and forearm and Smart Photo-Tape SIPs for the hand), and Smart Photo-Tape ID. The major result was that the Smart Photo-Tape SIPs were significantly different when compared to their respective scaled inertial properties, with the hand segment producing the largest difference between the scaled SIPs and Smart Photo-Tape SIPs. The implication of this study is that researches or coaches can use the Smart Photo-Tape method to calculate participant specific SIPs for pitching arm kinetic analysis.

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48

Blackburn, Dane E. "A novel approach to calculating relative scattering parameter sensitivity in computer-aided design programs." Thesis, Virginia Polytechnic Institute and State University, 1988. http://hdl.handle.net/10919/80100.

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Relative sensitivity is a measure of the percentage change in a system parameter caused by a percentage change in a component parameter. The adjoint network method has previously been used by Monaco and Tiberio in the computation of relative scattering parameter sensitivity. A new approach is presented in this work which defines a bilinear equation and three constants that relate any component scattering parameter to any system scattering parameter. A computer-aided design program which implements this relative sensitivity in analysis and optimization is presented. Circuit analysis examples demonstrating sensitivity analysis and optimization are included. As a background for this work, computer-aided design concepts, such as network modeling, objective functions, Rosenbrock's optimization method, and the adjoint network method for estimating partial derivatives, are also presented.
Master of Science

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Zaman, Sadat. "A simple enhanced cavity model for microstrip patch antennas and calculations of optimized parameters using a genetic algorithm /." Thesis, McGill University, 2006. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=99552.

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There is a need in today's industry to model the resonant frequency of the rectangular microstrip patch antenna very accurately because of its narrow bandwidth and increased use in communication applications. In this thesis, the cavity model is presented and updated in order to accurately analyze microstrip patch antennas. Also a genetic algorithm (GA) is used to optimize the patch for length and width so that in turn the maximum resonant frequency could be determined. The enhanced cavity model is shown to give more accurate results than another popular model while still being quite a simple model. It is further demonstrated that the GA can provide the global maximum for resonant frequency given a range for length and width of the patch.

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50

Malkin, Ondík Irina. "Development, validation, and application of new relativistic methods for all-electron unrestricted two-component calculations of EPR parameters." [S.l.] : [s.n.], 2006. http://deposit.ddb.de/cgi-bin/dokserv?idn=980973600.

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Dissertations / Theses on the topic 'Parameters calculation'

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