Dissertations / Theses on the topic 'Transit method'
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Koppenhoefer, Johannes. "Searching for extra-solar planets with the transit method." Diss., lmu, 2009. http://nbn-resolving.de/urn:nbn:de:bvb:19-106531.
Full textGattolin, Elena. "Merge in Transit, a distribution method in the industrial environment." Thesis, Jönköping University, JTH, Industrial Engineering and Management, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-1334.
Full textIn a fast moving environment and in a globalized market, companies are searching efficient distribution methods that enable broad product assortment, lower level of inventories, shorter customer order fulfilment, lower transportation costs in order to achieve a more efficient procurement process and a improved customer service. This paper will focus on a new solution in supply chain design to solve these trade-offs between management cost cutting and higher customer level within markets characterized by an increasing globalisation. Merge in transit (MIT) distribution method allows companies to reduce inventory and transportation costs while guaranteeing a high customer perceived service level. It is a new technique in which goods shipped from several supply locations are consolidated into one final customer delivery. The company needs to coordinate shipments so that they arrive simultaneously and goods can be bundled and shipped immediately to the final customer for arrival on due date. Economical benefits and drawbacks will be investigated from a supply chain prospective.
Alsubai, Khalid. "Wide angle search for extrasolar planets by the transit method." Thesis, St Andrews, 2008. http://hdl.handle.net/10023/521.
Full textChen, Lijuan. "An efficient method to compute shortest paths in real road network /." View abstract or full-text, 2005. http://library.ust.hk/cgi/db/thesis.pl?IEEM%202005%20CHEN.
Full textGoodloe, John Bennett. "STANDARDIZED SUB-SCALE DYNAMOMETER SCALING METHOD FOR TRANSIT AND FREIGHT TRAIN APPLICATIONS." OpenSIUC, 2016. https://opensiuc.lib.siu.edu/theses/1899.
Full textLee, Sui-chun Macella. "The impact of Mass Transit Railway on land development in Hong Kong an analysis of the island line using expansion method /." Click to view the E-thesis via HKUTO, 1989. http://sunzi.lib.hku.hk/hkuto/record/B42574146.
Full textHughes, Arthur D. "Analysis of in-transit visibility as a method of reducing material lost in shipment." Monterey, California. Naval Postgraduate School, 1994. http://hdl.handle.net/10945/30913.
Full textNaylor, A. Ross. "Evaluation and clinical application of a new method of quantifying mean cerebral transit time." Thesis, University of Aberdeen, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.240668.
Full textGee, Wilfred T., Olivier Guyon, Josh Walawender, Nemanja Jovanovic, and Luc Boucher. "Project PANOPTES: a citizen-scientist exoplanet transit survey using commercial digital cameras." SPIE-INT SOC OPTICAL ENGINEERING, 2016. http://hdl.handle.net/10150/622806.
Full textChen, Aijing. "Bus Transit Passenger Origin-Destination Flow Estimation: Capturing Terminal Carry-Over Movements Using the Iterative Proportional Fitting Method." The Ohio State University, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=osu1593675738643412.
Full textLee, Sui-chun Macella, and 李萃珍. "The impact of Mass Transit Railway on land development in Hong Kong: an analysis of the island line usingexpansion method." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1989. http://hub.hku.hk/bib/B42574146.
Full textSavic, Radojka. "Improved pharmacometric model building techniques." Doctoral thesis, Uppsala University, Department of Pharmaceutical Biosciences, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-9272.
Full textPharmacometric modelling is an increasingly used method for analysing the outcome from clinical trials in drug development. The model building process is complex and involves testing, evaluating and diagnosing a range of plausible models aiming to make an adequate inference from the observed data and predictions for future studies and therapy.
The aim of this thesis was to advance the approaches used in pharmacometrics by introducing improved models and methods for application in essential parts of model building procedure: (i) structural model development, (ii) stochastic model development and (iii) model diagnostics.
As a contribution to the structural model development, a novel flexible structural model for drug absorption, a transit compartment model, was introduced and evaluated. This model is capable of describing various drug absorption profiles and yet simple enough to be estimable from data available from a typical trial. As a contribution to the stochastic model development, three novel methods for parameter distribution estimation were developed and evaluated; a default NONMEM nonparametric method, an extended grid method and a semiparametric method with estimated shape parameters. All these methods are useful in circumstances when standard assumptions of parameter distributions in the population do not hold. The new methods provide less biased parameter estimates, better description of variability and better simulation properties of the model. As a contribution to model diagnostics, the most commonly used diagnostics were evaluated for their usefulness. In particular, diagnostics based on individual parameter estimates were systematically investigated and circumstances which are likely to misguide modelers towards making erroneous decisions in model development, relating to choice of structural, covariate and stochastic model components were identified.
In conclusion, novel approaches, insights and models have been provided to the pharmacometrics community.
Implementation of these advances to make model building more efficient and robust has been facilitated by development of diagnostic tools and automated routines.
Georgieva, Iskra. "Searching for Exoplanets in K2 Data." Thesis, Luleå tekniska universitet, Rymdteknik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-70960.
Full textStrohl, Brandon A. "Empirical Assessment of the Iterative Proportional Fitting Method for Estimating Bus Route Passenger Origin-Destination Flows." The Ohio State University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=osu1261583295.
Full textHamacher, Duane Willis Physics Faculty of Science UNSW. "A search for transiting extrasolar planets from the southern hemisphere." Publisher:University of New South Wales. Physics, 2008. http://handle.unsw.edu.au/1959.4/40943.
Full textWeishaupt, Holger. "A study of power spectral densities of real and simulated Kepler light curves." Thesis, Linnéuniversitetet, Institutionen för fysik och elektroteknik (IFE), 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-45802.
Full textWeishaupt, Hrafn N. H. "Implementing a pipeline to search for transiting exoplanets : application to the K2 survey data." Thesis, Linnéuniversitetet, Institutionen för fysik och elektroteknik (IFE), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-79207.
Full textAL, ABD ASSAAD. "Comparaison des methodes de mesure, du flux des contenus digestifs chez le ruminant : application a l'etude de la digestion de trois types de ration." Clermont-Ferrand 2, 1986. http://www.theses.fr/1986CLF21035.
Full textAlapini, Odunlade Aude Ekundayo Pauline. "Transiting exoplanets : characterisation in the presence of stellar activity." Thesis, University of Exeter, 2010. http://hdl.handle.net/10036/104834.
Full textCroxton, Keely L., Bernard Gendon, and Thomas L. Magnanti. "Models and Methods for Merge-In-Transit Operations." Massachusetts Institute of Technology, Operations Research Center, 2001. http://hdl.handle.net/1721.1/5135.
Full textFan, Lang. "Metaheuristic methods for the urban transit routing problem." Thesis, Cardiff University, 2009. http://orca.cf.ac.uk/54237/.
Full textBucciarelli, Mark. "Cluster sampling methods for monitoring route-level transit ridership." Thesis, Massachusetts Institute of Technology, 1991. http://hdl.handle.net/1721.1/13485.
Full textKotol, Martin. "Výkonová bilance laserového dálkoměru." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2014. http://www.nusl.cz/ntk/nusl-220580.
Full textOliver-Taylor, A. "Parallel transit methods for arterial spin labelling magnetic resonance imaging." Thesis, University College London (University of London), 2013. http://discovery.ucl.ac.uk/1382488/.
Full textJiang, Yu, and 姜宇. "Reliability-based transit assignment : formulations, solution methods, and network design applications." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2014. http://hdl.handle.net/10722/207991.
Full textMoreira, Joana Conceição 1975. "The use of market research methods in understanding choice transit riders." Thesis, Massachusetts Institute of Technology, 2000. http://hdl.handle.net/1721.1/80950.
Full textAwiphan, Supachai. "Exomoons to Galactic structure : high precision studies with the microlensing and transit methods." Thesis, University of Manchester, 2017. https://www.research.manchester.ac.uk/portal/en/theses/exomoons-to-galactic-structure-high-precision-studies-with-the-microlensing-and-transit-methods(7b257bb2-d0ad-4d47-afb8-5c691486cf9b).html.
Full textZhu, Yi Ph D. Massachusetts Institute of Technology. "Spatiotemporal learning and geo-visualization methods for constructing activity-travel patterns from transit card transaction data." Thesis, Massachusetts Institute of Technology, 2014. http://hdl.handle.net/1721.1/93807.
Full textCataloged from PDF version of thesis.
Includes bibliographical references (pages 149-157).
The study of human activity-travel patterns for transportation demand forecast has evolved a long way in theories, methodologies and applications. However, the scarcity of data has become a major barrier for the advancement of research in the field. At the same time, the proliferation of urban sensing and location-based devices generate voluminous streams of spatio-temporal registered information. These urban sensing data contain massive information on urban dynamics and individuals' mobility. For example, the transit smart card transaction data reveal the places that transit passengers visit at different times of day. As tempting as it appears to be, the incorporation of these urban sensing data into activity-travel study remains a big challenge, which demands new analytics, theories and frameworks to bridge the gap between the information observed directly from the imperfect urban sensing data and the knowledge about how people use the city. In this study, we propose a framework of analysis that focuses on the recurring processing and learning of voluminous transit smart card data flows in juxtaposition with additional auxiliary spatio-temporal data, which are used to improve our understanding of the context of the data. The framework consists of an ontology-based data integration process, a built environment measurement module, an activity-learning module and visualization examples that facilitate the exploration and investigation of activity-travel patterns. The ontology-based data integration approach helps to integrate and interpret spatio-temporal data from multiple sources in a systematic way. These spatio-temporally detailed data are used to formulate quantitative variables for the characterization of the context under which the travelers made their transit trips. In particular, a set of spatial metrics are computed to measure different dimensionalities of the urban built environment of trip destinations. In order to understand why people make trips to destinations, researchers and planners need to know the possible activities associated with observed transit trips. Therefore, an activity learning module is developed to infer the unknown activity types from millions of trips recorded in transit smart card transactions by learning the context dependent behaviors of travelers from a traditional household travel survey. The learned activities not only help the interpretation of the behavioral choices of transit riders, but also can be used to improve the characterization of urban built form by uncovering the likely activity landscapes of various places. The proposed framework and the methodology is demonstrated by focusing on the use of transit smart card transaction data, i.e., EZ-Link data, to study activity-travel patterns in Singapore. Although different modules of the framework are loosely coupled at the moment, we have tried to pipeline as much of the process as possible to facilitate efficient data processing and analysis. This allows researchers and planners to keep track of the evolution of human activity-travel patterns over time, and examine the correlations between the changes in activities and the changes in the built environment. The knowledge gained from continuous urban sensing data will certainly help policy makers and planners understand the current states of urban dynamics and monitor changes as transportation infrastructure and travel behaviors evolve over time.
by Yi Zhu.
Ph. D. in Urban and Regional Planning
Mitchell, B. J. "GLOBAL EXPLORATION OF TITAN’S CLIMATE: OFF THE SHELF TECHNOLOGY AND METHODS AS AN ENABLER." International Foundation for Telemetering, 1995. http://hdl.handle.net/10150/608541.
Full textRecent narrow band imagery of the surface of Titan reveals a very non-uniform surface. While there are no global oceans of liquid ethane/methane as once conjectured, the imagery does suggest the possibility of seas or lakes of liquid ethane, methane, and other organic materials. If these exist, Titan could be considered a gigantic analog model of the Earth's climate system complete with land masses, moderately thick atmosphere, and large bodies of liquid. By studying the climate of Titan, we could gain further understanding of the processes and mechanisms that shape the Earth's climate. Reuse of existing technology and methods may be a way to speed development and lower costs for the global study of Titan. Surprisingly, one of the key technologies could be a Transit or Global Positioning System (GPS) descendant for use in tracking probes wandering the surface of Titan.
Lundergan, Ryan W. "Parking regulation strategies and policies to support transit-oriented development." Amherst, Mass. : University of Massachusetts Amherst, 2009. http://scholarworks.umass.edu/theses/365/.
Full textLouisell, William. "A Framework and Analytical Methods for Evaluation of Preferential Treatment for Emergency and Transit Vehicles at Signalized Intersections." Diss., Virginia Tech, 2003. http://hdl.handle.net/10919/26820.
Full textPh. D.
Shulman, Katharine. "Paintings in Transit: A New Means For Protection of Collections, Balancing Traditional and Modern Conservation Philosophies and Methods." Scholarship @ Claremont, 2015. http://scholarship.claremont.edu/scripps_theses/697.
Full textRackham, Benjamin V., Dániel Apai, and Mark S. Giampapa. "The Transit Light Source Effect: False Spectral Features and Incorrect Densities for M-dwarf Transiting Planets." IOP PUBLISHING LTD, 2018. http://hdl.handle.net/10150/627040.
Full textKuhlman, Kristopher Lee. "Laplace Transform Analytic Element Method for Transient Groundwater Flow Simulation." Diss., The University of Arizona, 2008. http://hdl.handle.net/10150/193735.
Full textGrigorian, Zachary. "Modeling, Discontinuous Galerkin Approximation and Simulation of the 1-D Compressible Navier Stokes Equations." Thesis, Virginia Tech, 2019. http://hdl.handle.net/10919/93197.
Full textMaster of Science
In this thesis we derive time dependent equations that govern the physics of a fluid flowing through a one dimensional pipe. This model includes all error terms that result from 1D modeling approximations. The final model assumes that all of these error terms are negligible which is a standard assumption in industry. Steady state equations result when all time dependence is removed from the 1D equations. We approximate the true solution by a discontinuous piece-wise linear function. Standard techniques are used to solve for this approximate solution. We investigate two methods for solving the steady state equations. In the first method, one makes an educated guess about the solution profile and uses Newton’s method to solve for the true solution. The second method, pseudo-transient initialization, attempts to improve this initial guess through dynamic simulation. In this method, an initial guess is treated as the initial conditions for dynamic simulation. The dynamic simulation is then run for a fixed amount of time. The solution at the end of the simulation is the improved initial guess for Newton’s method and is used to solve for the steady state profile. To test the pseudo-transient initialization, we determine the number of function evaluations required to obtain the steady state solution for an initial guess with and without performing pseudo-transient initialization on it. We demonstrate that for the systems considered here, the pseudo-transient initialization algorithm reduced overall computational costs. Also, we observe that non-uniform meshing can significantly reduce model size while retaining accuracy. Several numerical experiments were conducted to illustrate these ideas. Finally, we close with suggestions for future research.
Das, Samik. "Ultrasonic Field Modeling in Non-Planar and Inhomogeneous Structures Using Distributed Point Source Method." Diss., The University of Arizona, 2008. http://hdl.handle.net/10150/195602.
Full textBezuidenhout, Johannes Jurie. "Convective heat flux determination using surface temperature history measurements and an inverse calculation method." Thesis, Virginia Tech, 2000. http://hdl.handle.net/10919/35706.
Full textThe objective of this study is therefore to develop a cost-effective single gage that can be used to measure both skin friction and heat flux. The method proposed in this study is to install a coaxial thermocouple into an existing skin friction gage to measure the unsteady temperature on the surface of the gage. By using the temperature history and a computer program the heat flux through the surface can be obtained through an iterative guessing method. To ensure that the heat flux through the gage is similar to the heat flux through the rest of the surface, the gage is manufactured of a material very similar to the rest of the surface.
Walker developed a computer program capable of predicting the heat flux through a surface from the measured surface temperature history. The program is based on an inverse approach to calculate the heat flux through the surface. The biggest advantages of this method are its stability and the small amount of noise induced into the system. The drawback of the method is that it is limited to semi-infinite objects. For surfaces with a finite thickness, a second thermocouple was installed into the system some distance below the first thermocouple. By modifying the computer program these two unsteady temperatures can be used to predict the heat flux through a surface of finite thickness.
As part of this study, the effect of noise induced by the Cook-Felderman technique, found in the literature were investigated in detail and it was concluded that the method proposed in this study is superior to this Cook-Felderman method. Heat flux measurements compared well with measurements recorded with heat flux gages. In all cases evaluated the difference was less than 20%. It can therefore be concluded that heat flux gages on their own can measure surface heat flux very accurately. These gages are however too large to install in a skin-friction gage. The method introduced in this study is noisier than the heat flux gages on their own, but the size which is very important, is magnitudes smaller when using a coaxial thermocouple, to measure the surface temperature history.
Master of Science
Wang, Mianzhi. "Numerical Analysis of Transient Teflon Ablation with a Domain Decomposition Finite Volume Implicit Method on Unstructured Grids." Digital WPI, 2012. https://digitalcommons.wpi.edu/etd-theses/284.
Full textCarvalho, Rafael Aleixo de. "Tempo de transito em meios com isotropia transversal vertical (VTI) : aproximações e inversão dos parametros." [s.n.], 2009. http://repositorio.unicamp.br/jspui/handle/REPOSIP/307310.
Full textTese (doutorado) - Universidade Estadual de Campinas, Instituto de Matematica, Estatistica e Computação Cientifica
Made available in DSpace on 2018-08-14T00:48:52Z (GMT). No. of bitstreams: 1 Carvalho_RafaelAleixode_D.pdf: 9585016 bytes, checksum: 31508e558a4b01742760ced71847289a (MD5) Previous issue date: 2009
Resumo: Como os alvos de exploração tornaram-se mais profundos, os comprimentos dos cabos têm aumentado em conformidade, fazendo a aproximação hiperbólica convencional produzir tempos de trânsito cada vez mais imprecisos. Em outras palavras, para as modernas geometrias de aquisição para grandes afastamentos, a aproximação hiperbólica já não é suficiente para horizontalizar a família CMP por causa da não homogeneidade ou anisotropia dos meios. Para resolver este problema, muitas fórmulas para o tempo de trânsito foram propostas na literatura que fornecem aproximações de qualidade diferente. Demonstrou-se que para meios com isotropia transversal vertical (meios VTI), apenas dois parâmetros do tempo de trânsito são suficientes para a realização de todo o processamento temporal, sendo a velocidade NMO e um parâmetro de anisotropia. Por isso, nesta tese, nos concentramos, na dedução de aproximações simples para o tempo de trânsito que dependem de um único parâmetro de anisotropia. Começamos por dar uma visão geral de uma coleção de tais aproximações para o tempo de trânsito encontradas na literatura e comparar suas qualidades. Em seguida, deduzimos um conjunto de novas aproximações para o tempo de trânsito que dependem de um parâmetro baseado em aproximações encontradas na literatura. A principal vantagem das nossas aproximações é que algumas delas são expressões analíticas bastante simples que as tornam fáceis de serem utilizadas, ao mesmo tempo que têm a mesma qualidade ou maior que as fórmulas já estabelecidas. Utilizamos estas aproximações para o tempo de trânsito para uma inversão dos parâmetros de anisotropia. Utilizando uma estimativa da velocidade NMO a partir da análise de velocidades hiperbólica, pode-se estimar o parâmetro anisotrópico a partir de uma aproximação para o tempo de trânsito mais geral. Estendemos o procedimento em dois passos utilizando um termo não hiperbólico mais preciso na aproximação para o tempo de trânsito. As aproximações para o tempo de trânsito deduzidas permitem predizer o viés na estimativa da velocidade NMO, proporcionando assim um meio de corrigir, tanto a estimativa a velocidade NMO, quanto o conseqüente valor do parâmetro de anisotropia. Por meio de um exemplo numérico, demonstramos que a estimativa dos parâmetros do tempo de trânsito, usando este processo iterativo, apresenta considerável melhora. Palavras-chave: Aproximação para tempos de trânsito, meios VTI, análise de velocidade e geofísica
Abstract: As exploration targets have become deeper, cable lengths have increased accordingly, making the conventional two term hyperbolic traveltime approximation produce increasingly erroneous traveltimes. In other words, for modern long-offset acquisition geometries, a hyperbolic traveltime approximation is no longer sufficient to flatten the CMP gather because of medium inhomogeneity or anisotropy. To overcome this problem, many traveltime formulas were proposed in the literature that provide approximations of different quality. It has been demonstrated that for transversly isotropic media with a vertical symmetry axis (VTI media), just two traveltime parameters are sufficient to perform all time-related processing, being the NMO velocity and one anisotropy parameter. Therefore, we concentrate in this thesis,on simple traveltime approximations that depend on a single anisotropy parameter. We start by giving an overview of a collection of such traveltime approximations found in the literature and compare their quality. Next, we derive a set of new single-parameter traveltime approximations based on the ones found in the literature. The main advantage of our approximations is that some of them are rather simple analytic expressions that make them easy to use, while achieving the same quality as the better of the established formulas. We then use these traveltime aproximations for an inversion of the anisotropy parameters. Using an estimate of the NMO velocity from a hyperbolic velocity analysis, one can estimate the anisotropic parameter from a more general traveltime approximation. We extend this two-step procedure using a more accurate nonhyperbolicity term in the traveltime approximation. The used traveltime approximations allow to predict the bias in the NMO velocity estimate, thus providing a means of correcting both the estimated NMO velocity and the resulting anisotropy parameter value. By means of a numerical example, we demonstrate that the estimation of the traveltime parameters, using this iterative procedure, is improved considerably. Keywords: Traveltime approximations, VTI media, velocity analysis and geophysics
Doutorado
Geofisica Computacional
Doutor em Matemática Aplicada
Adams, Bruce Keith. "The use of scintigraphy to study gastric emptying, motility and small intestinal transit in patients who have ingested a selection of common poisons." Doctoral thesis, University of Cape Town, 1995. http://hdl.handle.net/11427/27036.
Full textMa, Manyou. "A comparative evaluation of two Synthetic Transmit Aperture with Virtual Source beamforming methods in biomedical ultrasound." Thesis, University of British Columbia, 2015. http://hdl.handle.net/2429/56244.
Full textApplied Science, Faculty of
Electrical and Computer Engineering, Department of
Graduate
Al, Marhoon Hussain Hassan. "A Practical Method for Power Systems Transient Stability and Security." ScholarWorks@UNO, 2011. http://scholarworks.uno.edu/td/114.
Full textKoutsouris, Dionissios. "Etude de la deformabilite erythrocytaire par la methode du debit initial de filtration et l'analyse du temps de transit cellulaire." Paris 5, 1987. http://www.theses.fr/1987PA05S015.
Full textWood, Stephen L. "Modeling of Pipeline Transients: Modified Method of Characteristics." FIU Digital Commons, 2011. http://digitalcommons.fiu.edu/etd/456.
Full textZhu, Ruiying. "An eigenmatrices method to obtain transient solutions for the M/M/k:(N/FIFO) queueing system (k=1,2)." Ohio : Ohio University, 1991. http://www.ohiolink.edu/etd/view.cgi?ohiou1183989760.
Full textTsia, Man Juliana. "Positron deep level transient spectroscopy in semi-insulating GaAs using the positron velocity transient method." Hong Kong : University of Hong Kong, 2000. http://sunzi.lib.hku.hk/hkuto/record.jsp?B22424775.
Full text謝敏 and Man Juliana Tsia. "Positron deep level transient spectroscopy in semi-insulating GaAs using the positron velocity transient method." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2000. http://hub.hku.hk/bib/B3122524X.
Full textPetersen, Todd H. "A transient solver for current density in thin conductors for magnetoquasistatic conditions." Diss., Manhattan, Kan. : Kansas State University, 2009. http://hdl.handle.net/2097/1360.
Full textRamos, Gustavo Roberto. "Método multiescala para modelagem da condução de calor transiente com geração de calor : teoria e aplicação." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2015. http://hdl.handle.net/10183/133134.
Full textThis work deals with the modeling of transient heat conduction with heat generation in heterogeneous media, and its objective is to develop a proper multiscale model for this phenomenon. There already exist multiscale models in the literature related to this proposed problem, and which are valid for the following cases: (a) the representative volume element has a negligible size when compared to the characteristic macroscopic size (and, as a consequence, the microscale has a negligible thermal inertia); or (b) the heat generation is homogeneous at the microscale. On the other hand, the model proposed in this thesis, which is developed using a variational description of the problem, can be applied to finite representative volume elements and in conditions in which the heat generation is heterogeneous at the microscale. The time discretization (finite difference) and the space discretizations at both the microscale and the macroscale (finite element method) are presented in details, together with the algorithms needed for implementing the solution of the problem. In this thesis, simple numerical cases are presented, aiming to verify not only the theoretical multiscale model developed, but also its implementation. For this, it is analyzed, for instance, (a) cases in which the microscale is taken as a homogeneous material, making it possible the comparison of the multiscale solution with the conventional solution (one single scale) by the finite element method, and (b) a case in a heterogeneous material for which the full solution, that is, modeling all constituents directly on the macroscale, is obtained, making it possible the comparison with the multiscale solution. The solution at the microscale for several cases analyzed in this thesis suffers a large influence of the microscale thermal inertia. To demonstrate the application potential of the multiscale model, the cure of a carbon black loaded elastomer is simulated. Although the simulation shows that the thermal inertia does not have to be considered for this case in particular, the application of the present methodology makes it possible to model the cure of the elastomer directly at the microscale, an approach not used in multiscale methods context until now. This methodology opens the possibility for future improvements of the state of cure modeling.
Erhart, Kevin. "EFFICIENT LARGE SCALE TRANSIENT HEAT CONDUCTION ANALYSIS USING A PARALLELIZED BOUNDARY ELEMENT METHOD." Master's thesis, University of Central Florida, 2006. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/2973.
Full textM.S.M.E.
Department of Mechanical, Materials and Aerospace Engineering;
Engineering and Computer Science
Mechanical Engineering