Dissertations / Theses on the topic 'Boundary estimation'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 dissertations / theses for your research on the topic 'Boundary estimation.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.
Mu, Yingfei. "Boundary Estimation." Diss., North Dakota State University, 2015. http://hdl.handle.net/10365/25195.
Full textPasha, Hasan G. "Estimation of Static Stiffnesses from Free Boundary Dynamic (FRF) Measurements." University of Cincinnati / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1416569956.
Full textYANG, FAN Carolan Christopher. "ESTIMATION OF THE PROBABILITY A BROWNIAN BRIDGE CROSSES A CONCAVE BOUNDARY." [Greenville, N.C.] : East Carolina University, 2010. http://hdl.handle.net/10342/2798.
Full textWright, Andrew D. "Acoustic boundary condition estimation in a near-scale gas-turbine combustor." Thesis, This resource online, 1996. http://scholar.lib.vt.edu/theses/available/etd-08222008-063430/.
Full textZhang, Hanzhong. "A moving boundary problem in a distributed parameter system with application to diode modeling." Access restricted to users with UT Austin EID, 2001. http://wwwlib.umi.com/cr/utexas/fullcit?p3037035.
Full textMonokrousos, Antonios. "Optimisation and control of boundary layer flows." Licentiate thesis, Stockholm : Skolan för teknikvetenskap, Kungliga Tekniska högskolan, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-10652.
Full textVan, der Kamp Derek. "Ceilometer observations of Vancouver's urban boundary layer : validation and mixed-layer height estimation." Thesis, University of British Columbia, 2008. http://hdl.handle.net/2429/1599.
Full textRuda, Harald. "Estimation of the parameters of a boundary contour system using psychophysical hyperacuity experiments." Thesis, Boston University, 2013. https://hdl.handle.net/2144/12843.
Full textVisual hyperacuity enables observers to make accurate judgments of the relative positions of stimuli when the differences are smaller than the size of a single cone in the fovea. Because hyperacuity can serve as a gauge for precisely measuring characteristics of the visual system, it can provide stringent tests for models of the visual system. A variant of the Boundary Contour System (BCS) model is here used to clarify previously unexplained psychophysical hyperacuity results involving contrast polarity, stimulus separation, and sinusoidal masking gratings. Two-dot alignment thresholds were studied by Levi & Waugh (1996) by varying the gap between the dots, with same and opposite contrast polarity with respect to the background, and also with and without band-limited sinusoidal grating masks of different orientations. They found that when the gap between the dots is small (6 arcmin), different patterns of misalignment thresholds are obtained for the same and different contrast polarity conditions. However, when the gap is large (24 arcmin), the same pattern of thresholds was obtained irrespective of contrast polarity. The simulations presented here replicate these findings, producing the same pattern of results when varying the gap between the dots, with same and opposite contrast polarity with respect to the background, and also with and without sinusoidal grating masks of different orientations. The vision model used (BCS) is able to produce these patterns because of its inherent processing using contrast insensitivity, spatial and oriented competition, and long-range completion layers. A novel aspect of the model is the use of sampled field processing, which simplifies the model's equations. Modified Hebbian learning and a neural decision module are proposed as mechanisms that link the vision model's outputs to a decision criterion. All model parts have plausible neurobiological correlates. In addition, psychophysical hyperacuity experiments served to map the limits of inhibitory spatial interactions. The results show that inhibition occurs even when only half of the split flanking line of Badcock & Westheimer (1985b) is used, suggesting that subthreshold activity in units representing the line extends beyond the end of the line. Furthermore, strong inhibition was observed with a flanking illusory line grating.
Freeman, Matthew A. "Multi-area power system state estimation utilizing boundary measurements and phasor measurement units ( PMUs)." Thesis, Texas A&M University, 2006. http://hdl.handle.net/1969.1/4178.
Full textSun, Walter. "Learning the dynamics of deformable objects and recursive boundary estimation using curve evolution techniques." Thesis, Massachusetts Institute of Technology, 2005. http://hdl.handle.net/1721.1/34978.
Full textThis electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Includes bibliographical references (p. 161-176).
The primary objective of this thesis is to develop robust algorithms for the incorporation of statistical information in the problem of estimating object boundaries in image data. We propose two primary algorithms, one which jointly estimates the underlying field and boundary in a static image and another which performs image segmentation across a temporal sequence. Some motivating applications come from the earth sciences and medical imaging. In particular, we examine the problems of oceanic front and sea surface temperature estimation in oceanography, soil boundary and moisture estimation in hydrology, and left ventricle boundary estimation across a cardiac cycle in medical imaging. To accomplish joint estimation in a static image, we introduce a variational technique that incorporates the spatial statistics of the underlying field to segment the boundary and estimate the field on either side of the boundary. For image segmentation across a sequence of frames, we propose a method for learning the dynamics of a deformable boundary that uses these learned dynamics to recursively estimate the boundary in each frame over time. In the recursive estimation algorithm, we extend the traditional particle filtering approach by applying sample-based methods to a complex shape space.
(cont.) We find a low-dimensional representation for this shape-shape to make the learning of the dynamics tractable and then incorporate curve evolution into the state estimates to recursively estimate the boundaries. Experimental results are obtained on cardiac magnetic resonance images, sea surface temperature data, and soil moisture maps. Although we focus on these application areas, the underlying mathematical principles posed in the thesis are general enough that they can be applied to other applications as well. We analyze the algorithms on data of differing quality, with both high and low SNR data and also full and sparse observations.
by Walter Sun.
Ph.D.
Åkervik, Espen. "Global stability and feedback control of boundary layer flows." Doctoral thesis, KTH, Linné Flow Center, FLOW, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-9547.
Full textQC 20100924
Saeed, Umar. "Atmospheric-boundary-layer height retrieval using microwave radiometer and lidar sensors : algorithms and error estimation." Doctoral thesis, Universitat Politècnica de Catalunya, 2016. http://hdl.handle.net/10803/396606.
Full textLa altura de Capa Límite Atmosférica ("Atmospheric Boundary Layer Height", ABLH) es un parámetro importante en la predicción del tiempo, la meteorología, la aviónica, y los modelos de calidad del aire y dispersión. El desarrollo local de la Capa Límite Atmosférica (ABL) durante el ciclo diurno completo es una función de múltiples parámetros que, entre otros, incluyen la ubicación geográfica del lugar, su topografía, época del año, y las condiciones de día y de noche. Existen múltiples instrumentos de teledetección y métodos para recuperar la ABLH, sin embargo, ninguno de ellos es capaz de medir completamente el desarrollo de la ABL bajo cualquier condición atmosférica. Esta tesis doctoral versa sobre la estimación de la ABLH durante el ciclo diurno completo (capa de mezcla diurna, capa límite estable nocturna, y capa límite en la transición mañana / tarde), mediante radiómetros de microondas (MWR) y ceilómetros (principio lidar) como instrumentos terrestres de teledetección, así como las técnicas de procesado de la señal relacionadas. Como referencia se utilizan las estimaciones de la ABLH procedentes de lidar Doppler y radiosondeos. Meta de esta tesis es también la combinación de los datos procedentes de estos dos instrumentos a fin de explotar sus fortalezas individuales y superar sus limitaciones. En este contexto, la tesis se estructura en torno a tres objetivos principales: En primer lugar, se presenta un método sinérgico para la estimación de la altura de la capa de mezcla (MLH). Con este fin, se analizan y comparan las incertezas en la estimación de la MLH obtenida a partir de las señales retrodispersadas medidas por el ceilómetro y los perfiles de temperatura recuperados por el MWR. Mientras que el filtro de Kalman extendido (EKF) se utiliza como filtro adaptativo para procesar las señales de retrodispersión lidar del ceilómetro, el "parcel method" se utiliza para tratar el perfil de temperatura potencial recuperado por el MWR. Por último, los dos métodos se combinan en una nueva metodología para la recuperación sinérgica de la MLH. En segundo lugar, se investigan métodos, no sinérgicos y sinérgicos, para la estimación de la altura de la capa límite estable (SBLH) nocturna a partir de datos procedente del ceilómetro y del MWR. La SBLH a partir de la señales retrodispersadas medidas por el ceilómetro se recupera utilizando Regiones de Mínima Varianza (MVR) como trazadores de la estratificación de los aerosoles en la SBL. Para el MWR, se utilizan modelos físicos idealizados de la literatura para estimar la SBLH. A continuación, se desarrolla un método sinérgico de recuperación de la SBLH que combina las medidas de ambos instrumentos. Por último, se presenta un estudio preliminar sobre la viabilidad del Large Eddy Simulation (LES) como herramienta de estudio de la ABL. En esta línea, los perfiles de retrodispersión lidar y los perfiles de temperatura potencial simulados mediante LES se comparan con las medidas procedentes de estos dos instrumentos. Además, se presenta un nuevo método para la recuperación directa de la MLH a partir de mediciones de temperatura de brillo simuladas mediante LES, lo cual, evita la necesidad de recuperar el perfil de temperatura física primero. También se investiga el impacto de los errores de inversión en las estimaciones de la MLH. Las técnicas desarrolladas en esta tesis doctoral han sido probadas en la campaña de medidas HOPE (Jülich, Alemania), donde se han considerado diferentes casos de prueba bajo diferentes condiciones atmosféricas
L'altura de Capa Límit Atmosfèrica ("Atmospheric Boundary Layer Height", ABLH) és un paràmetre important en la predicció del temps, la meteorologia, l'aviònica, i els models de qualitat de l'aire i dispersió. El desenvolupament local de la Capa Límit Atmosfèrica (ABL) durant el cicle diürn complet és una funció de múltiples paràmetres que, entre d'altres, inclouen la ubicació geogràfica del lloc, la seva topografia, època de l'any, i les condicions de dia i de nit. Hi ha múltiples instruments de teledetecció i mètodes per recuperar la ABLH, però, cap d'ells és capaç de mesurar completament el desenvolupament de l'ABL sota qualsevol condició atmosfèrica. Aquesta tesi doctoral versa sobre l'estimació de la ABLH durant el cicle diürn complet (capa de mescla diürna, capa límit estable nocturna, i capa límit en la transició matí / tarda), mitjançant radiòmetres de microones (MWR) i ceilòmetres (principi lidar) com a instruments terrestres de teledetecció, així com les tècniques de processament del senyal relacionades. Com a referència s'utilitzen les estimacions de la ABLH procedents de lidar Doppler i radiosondatges. Meta d'aquesta tesi és també la combinació de les dades procedents d'aquests dos instruments a fi d'explotar les seves fortaleses individuals i superar les seves limitacions. En aquest context, la tesi s'estructura al voltant de tres objectius principals: En primer lloc, es presenta un mètode sinèrgic per a l'estimació de l'alçada de la capa de mescla (MLH). Amb aquesta finalitat, s'analitzen i comparen les incerteses en l'estimació de la MLH obtinguda a partir dels senyals retrodispersats mesurats pel ceilòmetre i els perfils de temperatura recuperats pel MWR. Mentre que el filtre de Kalman estès (EKF) s'utilitza com a filtre adaptatiu per processar els senyals de retrodispersió lidar del ceilòmetre, el "parcel method" s'utilitza per tractar el perfil de temperatura potencial recuperat pel MWR. Finalment, els dos mètodes es combinen en una nova metodologia per a la recuperació sinèrgica de la MLH.En segon lloc, s'investiguen mètodes, no sinèrgics i sinèrgics, per a l'estimació de l'alçada de la capa límit estable (SBLH) nocturna a partir de dades procedent del ceilòmetre i del MWR. La SBLH a partir dels senyals retrodispersats mesurats pel ceilòmetre es recupera utilitzant Regions de Mínima Variància (MVR) com a traçadors de l'estratificació dels aerosols a la SBL. Pel MWR, s'utilitzen models físics idealitzats de la literatura per estimar la SBLH. A continuació, es desenvolupa un mètode sinèrgic de recuperació de la SBLH que combina les mesures de tots dos instruments.Finalment, es presenta un estudi preliminar sobre la viabilitat del Large Eddy Simulation (LES) com a eina d'estudi de l'ABL. En aquesta línia, els perfils de retrodispersió lidar i els perfils de temperatura potencial simulats mitjançant LES es comparen amb les mesures procedents d'aquests dos instruments. A més, es presenta un nou mètode per a la recuperació directa de la MLH a partir de mesuraments de temperatura de brillantor simulades mitjançant LES, la qual cosa, evita la necessitat de recuperar el perfil de temperatura física primer. També s'investiga l'impacte dels errors d'inversió en les estimacions de la MLH.Les tècniques desenvolupades en aquesta tesi doctoral han estat provades en la campanya de mesures HOPE (Jülich, Alemanya), on s'han considerat diferents casos de prova sota diferents condicions atmosfèriques.
Fox, Colin. "Conductance imaging : estimation of isotropic conductance perturbations from low-frequency boundary measurements in circular geometries." Thesis, University of Cambridge, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.303010.
Full textSehlstedt, Niklas. "Hybrid methods for inverse force estimation in structural dynamics." Doctoral thesis, KTH, Vehicle Engineering, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3528.
Full textStrydom, Willem Jacobus. "Recovery based error estimation for the Method of Moments." Thesis, Stellenbosch : Stellenbosch University, 2015. http://hdl.handle.net/10019.1/96881.
Full textENGLISH ABSTRACT: The Method of Moments (MoM) is routinely used for the numerical solution of electromagnetic surface integral equations. Solution errors are inherent to any numerical computational method, and error estimators can be effectively employed to reduce and control these errors. In this thesis, gradient recovery techniques of the Finite Element Method (FEM) are formulated within the MoM context, in order to recover a higher-order charge of a Rao-Wilton-Glisson (RWG) MoM solution. Furthermore, a new recovery procedure, based specifically on the properties of the RWG basis functions, is introduced by the author. These recovered charge distributions are used for a posteriori error estimation of the charge. It was found that the newly proposed charge recovery method has the highest accuracy of the considered recovery methods, and is the most suited for applications within recovery based error estimation. In addition to charge recovery, the possibility of recovery procedures for the MoM solution current are also investigated. A technique is explored whereby a recovered charge is used to find a higher-order divergent current representation. Two newly developed methods for the subsequent recovery of the solenoidal current component, as contained in the RWG solution current, are also introduced by the author. A posteriori error estimation of the MoM current is accomplished through the use of the recovered current distributions. A mixed second-order recovered current, based on a vector recovery procedure, was found to produce the most accurate results. The error estimation techniques developed in this thesis could be incorporated into an adaptive solver scheme to optimise the solution accuracy relative to the computational cost.
AFRIKAANSE OPSOMMING: Die Moment Metode (MoM) vind algemene toepassing in die numeriese oplossing van elektromagnetiese oppervlak integraalvergelykings. Numeriese foute is inherent tot die prosedure: foutberamingstegnieke is dus nodig om die betrokke foute te analiseer en te reduseer. Gradiënt verhalingstegnieke van die Eindige Element Metode word in hierdie tesis in die MoM konteks geformuleer. Hierdie tegnieke word ingespan om die oppervlaklading van 'n Rao-Wilton-Glisson (RWG) MoM oplossing na 'n verbeterde hoër-orde voorstelling te neem. Verder is 'n nuwe lading verhalingstegniek deur die outeur voorgestel wat spesifiek op die eienskappe van die RWG basis funksies gebaseer is. Die verhaalde ladingsverspreidings is geïmplementeer in a posteriori fout beraming van die lading. Die nuut voorgestelde tegniek het die akkuraatste resultate gelewer, uit die groep verhalingstegnieke wat ondersoek is. Addisioneel tot ladingsverhaling, is die moontlikheid van MoM-stroom verhalingstegnieke ook ondersoek. 'n Metode vir die verhaling van 'n hoër-orde divergente stroom komponent, gebaseer op die verhaalde lading, is geïmplementeer. Verder is twee nuwe metodes vir die verhaling van die solenodiale komponent van die RWG stroom deur die outeur voorgestel. A posteriori foutberaming van die MoM-stroom is met behulp van die verhaalde stroom verspreidings gerealiseer, en daar is gevind dat 'n gemengde tweede-orde verhaalde stroom, gebaseer op 'n vektor metode, die beste resultate lewer. Die foutberamingstegnieke wat in hierdie tesis ondersoek is, kan in 'n aanpasbare skema opgeneem word om die akkuraatheid van 'n numeriese oplossing, relatief tot die berekeningskoste, te optimeer.
McBride, Marvin B. "Estimation of stratocumulus-topped boundary layer depth using sea surface and remotely sensed cloud-top temperatures." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2000. http://handle.dtic.mil/100.2/ADA380378.
Full textThesis advisors, Durkee, Philip A. ; Wash, Carlyle H. "June 2000." Includes bibliographical references (p. 79-80). Also available in print.
Al-Romaih, Jamal S. "Stage-discharge assessment in meandering channels : conveyance estimation and boundary shear stress distribution in meandering channels." Thesis, University of Bradford, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.680818.
Full textWang, Xiuquan. "Parameter Estimation in the Advection Diffusion Reaction Model With Mean Occupancy Time and Boundary Flux Approaches." OpenSIUC, 2014. https://opensiuc.lib.siu.edu/dissertations/976.
Full textZhou, Mi. "Advancing Assessments on Aerosol Radiative Effect by Measurement-based Direct Effect Estimation and through Developing an Explicit Climatological Convective Boundary Layer Model." Diss., Georgia Institute of Technology, 2006. http://hdl.handle.net/1853/14091.
Full textTobias, Brännvall. "Source Term Estimation in the Atmospheric Boundary Layer : Using the adjoint of the Reynolds Averaged Scalar Transport equation." Thesis, Umeå universitet, Institutionen för fysik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-103671.
Full textDetta arbete utvärderar hurvida Reynolds medelvärdesmodellering inom flödessimuleringar kan användas till att finna källan till en viss gas baserat på verkliga mätningar ute i fält. Metoden går ut på att använda den adjungerade ekvationen till Reynolds tidsmedlade skalära transportekvationen, beskriven och härledd häri. Då bakåtmodellen bygger på framåtmodellen, måste såleds framåtmodellen utvärderas först. Navier-Stokes ekvationer med en turbulensmodell löses i en domän, innehållandes 4 kuber i en 2x2 orientering, för vilken en hastighetsprofil erhålles. Turbulensmodellen som användes är en union av två olika k-ε modeller, där den ena fångar turbulens runt tröga objekt och den andra som modellerar atmosfäriska gränsskiktet. Detta fält används sedan i framåtmodellen av skalära transportekvationen, som sedan jämförs med körningar från EnFlo windtunneln i Surrey. Slutligen testkörs även den adjungerade ekvationen, både för syntetiskt data genererat i framåtkörningen men även för data från EnFlo tunneln. Då det visade sig att det turbulenta Schmidttalet spelar stor roll inom spridning i det atmosfäriska gränsskiktet, gjordes testkörningar med tre olika Schmidttal, det normala 0.7, det väldigt låga talet 0.3 samt ett höjdberoende Schmidttal. Det visade sig att det vanligtvis använda talet 0.7 inte alls lyckas fånga spridningen tillfredställande och gav ett stort modellfel. Därför löstes den adjungerade ekvationen för 0.3 samt för ett höjdberoende Schmidttal. Interaktionen mellan mätningar, den riktiga källstyrkan (som är okänd i den adjungerade ekvationen) samt källpositionen är onekligen intrikat. Över- samt underestimationer av framåtmodellen kan ta ut varandra i bakåtmodellen för att finna rätt källa, med rätt källstyrka. Det ter sig som Reynolds turbulensmodellering mycket möjligt kan användas inom källtermsuppskattning.
Schlöder, Johannes P. "Numerische Methoden zur Behandlung hochdimensionaler Aufgaben der Parameteridentifizierung." Bonn : [s.n.], 1987. http://catalog.hathitrust.org/api/volumes/oclc/18814825.html.
Full textRau, Christian, and rau@maths anu edu au. "Curve Estimation and Signal Discrimination in Spatial Problems." The Australian National University. School of Mathematical Sciences, 2003. http://thesis.anu.edu.au./public/adt-ANU20031215.163519.
Full textBalsubramanian, Ravishankar. "Error estimation and grid adaptation for functional outputs using discrete-adjoint sensitivity analysis." Master's thesis, Mississippi State : Mississippi State University, 2002. http://library.msstate.edu/etd/show.asp?etd=etd-10032002-113749.
Full textGahard, Claude F. "An estimation of the ability to forecast boundary layer mixing height and wind parameters through forecast verification over Fort Ord." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2003. http://library.nps.navy.mil/uhtbin/hyperion-image/03sep%5FGahard.pdf.
Full textThesis advisor(s): Wendell A. Nuss, David S. Brown. Includes bibliographical references (p. 65-66). Also available online.
Boonvisut, Pasu. "Active Exploration of Deformable Object Boundary Constraints and Material Parameters Through Robotic Manipulation Data." Case Western Reserve University School of Graduate Studies / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=case1369078402.
Full textManomaiphiboon, Kasemsan. "Estimation of Emission Strength and Air Pollutant Concentrations by Lagrangian Particle Modeling." Diss., Georgia Institute of Technology, 2004. http://hdl.handle.net/1853/5141.
Full textLange, Vega Diego. "Lidar and S-band radar profiling of the atmosphere : adaptive processing for boundary-layer monitoring, optical-parameter error estimation, and application cases." Doctoral thesis, Universitat Politècnica de Catalunya, 2014. http://hdl.handle.net/10803/279246.
Full textLa tesis doctoral aborda la teledetecció atmosfèrica amb tècniques lidar i radar (banda S) i llur tractament del senyal. La teledetecció activa amb aquests instruments ofereix resolucions espacials i temporals sense precedents en la perfilometria vertical de l'atmosfera i recuperació de productes de dades òptics i físics atmosfèrics en un marc de creixent regulació mediambiental. El primer objectiu d'aquesta tesi concerneix l'estimació de cotes d'error en la inversió del perfil del coeficient de retrodispersió atmosfèrica a partir de senyals lidar de tipus elàstic (és a dir, sense desplaçament de la longitud d'ona en recepció al interactuar amb els dispersors atmosfèrics) mitjançant l'algorisme d'inversió de dues components de Klett-Fernald-Sasano. Aquest objectiu parteix de treballs previs en el Remote Sensing Lab. (RSLab) de la Universitat Politècnica de Catalunya (UPC) i permet obtenir cotes de primer ordre (aproximades) basades en propagació d'errors i cotes (exactes) basades en el increment total de l'error. Característica diferencial en front l'estat de l'art és l'assimilació d'errors sistemàtics (per exemple, entrades de cal.libració d'usuari) i aleatoris (relació senyal-soroll, SNR, finita) en forma matemàtica explícita. El segon objectiu, central de la tesis, aborda l'estimació de l'altura de la capa límit atmosfèrica (ABLH) a partir de senyal lidar elàstics i d'observacions radar en banda S (ona continua amb modulació en freqüència, FMCW) utilitzant tècniques adaptatives basades en filtrat estès de Kalman (EKF). El filtre es basa en modelat morfològic de la transició atmosfèrica entre la capa de mescla i la troposfera lliure i en l'estimació continua de la informació de covariança del soroll. En el prototipus lidar-EKF la tècnica proposada millora clarament les tècniques clàssiques d'estimació de la ABLH como són les basades en mètodes derivatius, decisió de llindar, o el mètode de la variança-centroide. La formulació EKF s'aplica tant a mesures procedents de ceilòmetres lidar como de la pròpia estació lidar UPC en escenes d'alta i baixa SNR. Addicionalment, l'enfoc lidar-EKF es reformula i s'estén amb èxit a escenes radar en banda S (dispersió Bragg) en presència de fonts de soroll interferent (dispersió Rayleigh de, per exemple, insectes i ocells). En aquest context, la característica FMCW permet la capacitat de resolució en distància. L'estimació de la ABLH amb els prototipus lidar-EKF i radar-EKF s'intercompara en campanyes de mesura. Finalment, el tercer objectiu atén a l'explotació de l'estació lidar UPC existent: En una primera part introductòria, es formula un algorisme modificat de "gluing" per a la millora del marge dinàmic de canals lidar elàstics mitjançant combinació (o "enganxat") de senyals lidar adquirits analògicament i amb foto-comptatge. En una segona part, es presenten dos exemples (incloent l'aplicació de l'algorisme de "gluing") que il.lustren les capacitats del lidar de la UPC en l'observació atmosfèrica de dos recents erupcions volcàniques des de la xarxa d'observació EARLINET (European Aerosol Research Lidar Network). Aquesta última és part de GALION (Global Atmospheric Watch Atmospheric Lidar Observation Network)-GEOSS (Global Earth Observation System of Systems).
Pettersson, Nicklas. "Multiple Kernel Imputation : A Locally Balanced Real Donor Method." Doctoral thesis, Stockholms universitet, Statistiska institutionen, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-89435.
Full textAt the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 1: In press. Paper 3: Submitted. Paper 4: Submitted.
Wang, Qi. "Estimation of Refractivity Conditions in the Marine Atmospheric Boundary Layer from Range and Height Measurement of X-band EM Propagation and Inverse Solutions." The Ohio State University, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=osu1565885420888906.
Full textKing, David R. "A bayesian solution for the law of categorical judgment with category boundary variability and examination of robustness to model violations." Thesis, Georgia Institute of Technology, 2013. http://hdl.handle.net/1853/52960.
Full textNadal, Soriano Enrique. "Cartesian grid FEM (cgFEM): High performance h-adaptive FE analysis with efficient error control. Application to structural shape optimization." Doctoral thesis, Universitat Politècnica de València, 2014. http://hdl.handle.net/10251/35620.
Full textCada d'¿a dise¿nos m'as complejos son requeridos por las industrias actuales. Para el dise¿no de nuevos componentes, los procesos tradicionales de prueba y error usados com'unmente ya no son v'alidos ya que ralentizan el proceso y dan lugar a dise¿nos sub-'optimos. Para componentes estructurales, una alternativa consiste en usar procesos de optimizaci'on de forma estructural los cuales dan como resultado dise¿nos 'optimos. Sin embargo, estas t'ecnicas requieren un alto coste computacional y tambi'en programas de Elementos Finitos (EF) extremadamente eficientes y robustos. Las compa¿n'¿as de programas de EF son conocedoras de que sus programas comerciales necesitan ser mejorados en este sentido y destinan importantes cantidades de recursos para mejorar sus c'odigos. En este trabajo proponemos usar el M'etodo de Elementos Finitos basado en mallados Cartesianos (cgFEM) como una herramienta eficiente y robusta para el an'alisis num'erico. La metodolog'¿a cgFEM desarrollada en esta tesis usa la sinergia entre varias t'ecnicas para lograr este prop'osito, cuyos dos ingredientes principales son el uso de los mallados Cartesianos de EF independientes de la geometr'¿a del componente que va a ser analizado y una eficiente estructura jer'arquica de datos. Estas dos caracter'¿sticas confieren a la tecnolog'¿a cgFEM de los requisitos necesarios para aumentar la eficiencia del c'odigo cgFEM con respecto a c'odigos comerciales. Como se indica en [1, 2], para garantizar la convergencia del proceso de optimizaci'on de forma estructural se necesita controlar el error en cada geometr'¿a analizada. En este sentido el c'odigo cgFEM tambi'en incorpora los apropiados estimadores de error. Estos estimadores de error han sido espec'¿ficamente adaptados al entorno cgFEM para aumentar su eficiencia. En esta tesis se introduce un proceso de recuperaci'on de la soluci'on, llamado SPR-CD, que en combinaci'on con el estimador de error de Zienkiewicz y Zhu [3], da como resultado medidas muy precisas del error de la soluci'on de EF. Adicionalmente, tambi'en se han desarrollado estimadores de error y cotas num'ericas en Magnitudes de Inter'es basadas en la t'ecnica SPR-CD para permitir un eficiente control de la calidad de la soluci'on num'erica. Respecto a la estimaci'on de error, tambi'en se presenta un proceso de estimaci'on de error para controlar la calidad del campo de tensiones recuperado obtenido mediante la t'ecnica SPR-CD. Ya que el campo recuperado es por lo general m'as preciso y tiene un mayor orden de convergencia que la soluci'on de EF, se propone sustituir la soluci'on de EF por la soluci'on recuperada para disminuir as'¿ el coste computacional del an'alisis num'erico. Todas estas mejoras se han reflejado en esta tesis mediante ejemplos num'ericos de problemas de optimizaci'on de forma estructural. Los resultados num'ericos muestran claramente un mejor comportamiento de la tecnolog'¿a cgFEM con respecto a implementaciones cl'asicas de EF com'unmente usadas en la industria.
Nadal Soriano, E. (2014). Cartesian grid FEM (cgFEM): High performance h-adaptive FE analysis with efficient error control. Application to structural shape optimization [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/35620
TESIS
Hou, Chuanchuan. "Vibration-based damage identification with enhanced frequency dataset and a cracked beam element model." Thesis, University of Edinburgh, 2016. http://hdl.handle.net/1842/20434.
Full textM, M. Galib Asadullah. "Robust wireless communications under co-channel interference and jamming." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/22571.
Full textCommittee Chair: Gordon L. Stuber; Committee Member: Alfred D. Andrew; Committee Member: John A. Buck; Committee Member: Steven W. McLaughlin; Committee Member: Ye (Geoffrey) Li.
Dekou, Tiomajou Raoul Florent. "Organisation à grandes échelles de la turbulence de paroi." Thesis, Ecole centrale de Lille, 2016. http://www.theses.fr/2016ECLI0006/document.
Full textThis study lies in the context of large scale coherent structures (uniform momentum regions and vortical motions) investigation in a near wall turbulent boundary layer at high Reynolds numbers (Reθ=9830 and Reθ=19660). With a Linear Stochastic Estimation procedure based on correlations computation, a full time-resolved 3 component field is reconstructed at high frequency from stereo-PIV at 4 Hz and hot wire data at 30 kHz . A DNS database of turbulent channel flow was used to validate the reconstruction method. To evaluate the quality of the method, reconstructed velocity fluctuations are compared to refence ones extracted directly from the DNS database. Furthermore, a statistical analysis is performed on HWA, PIV and LSE velocity fields. The results obtained are compared to those from Carlier and Stanislas (2005). Algorithms were developed to extract coherent structures from the reconstructed field. Uniform momentum regions are characterized with their mean hydraulic diameter in the YZ plane, their life time and their contribution to Reynolds stresses. The vortical motions are characterized by their position, radius, circulation and vorticity in addition to their life time and their number computed at a fixed position from the wall. The spatial organization of the structures was investigated through a correlation of their respective indicative functions in the spanwise direction . The simplified large scale model that arised is compared to the ones in the literature
Gunson, James Reginald. "Estimating open-ocean boundary conditions : sensitivity studies." Thesis, Massachusetts Institute of Technology, 1995. http://hdl.handle.net/1721.1/53024.
Full textIncludes bibliographical references (leaves 145-149).
by James Reginald Gunson.
Ph.D.
Pierson, William E. "Using boundary methods for estimating class separability /." The Ohio State University, 1998. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487951907958628.
Full textSaeed, Usman. "Adaptive numerical techniques for the solution of electromagnetic integral equations." Diss., Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/41173.
Full textLovón, Oscar Bayardo Ramos. "Formulação h-adaptativa do método dos elementos de contorno para elasticidade bidimensional com ênfase na propagação da fratura." Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/18/18134/tde-25092006-092346/.
Full textIn this work, an adaptative formulation of the boundary element method is developed to analyze linear elastic fracture problems. The collocation point method was used to formulate the integral equations for the displacements and stresses (or tractions). To discretize the integral equations, linear elements were used to obtain the exact expressions of the integrals over boundary elements and fracture. To construct the linear system of equations were used only displacement equations, traction equations or both of them written for opposite nodes of the fracture, leading to the dual boundary element formulation usually employed in the fracture analyses. For the process of growth of the crack a special procedure was developed aiming at the correct determination of the direction of growth of the crack. The stress intensity factors, to calculate he crack growth angle, are calculated through of correlation displacements technique which relates the displacements actuants in the faces of the crack. The employed adaptative model is the h-type where only the sub-division of the elements is done based on error estimate. The error estimates considered in this work are based on the following norms: displacement, traction and strain energy variations, this last considered from the integration over the boundary. Numerical examples are presented to demonstrate the efficiency of the proposed procedures.
Libengue, Dobele-kpoka Francial Giscard Baudin. "Méthode non-paramétrique des noyaux associés mixtes et applications." Thesis, Besançon, 2013. http://www.theses.fr/2013BESA2007/document.
Full textWe present in this thesis, the non-parametric approach using mixed associated kernels for densities withsupports being partially continuous and discrete. We first start by recalling the essential concepts of classical continuousand discrete kernel density estimators. We give the definition and characteristics of these estimators. We also recall thevarious technical for the choice of smoothing parameters and we revisit the problems of supports as well as a resolutionof the edge effects in the discrete case. Then, we describe a new method of continuous associated kernels for estimatingdensity with bounded support, which includes the classical continuous kernel method. We define the continuousassociated kernels and we propose the mode-dispersion for their construction. Moreover, we illustrate this on the nonclassicalassociated kernels of literature namely, beta and its extended version, gamma and its inverse, inverse Gaussianand its reciprocal, the Pareto kernel and the kernel lognormal. We subsequently examine the properties of the estimatorswhich are derived, specifically, the bias, variance and the pointwise and integrated mean squared errors. Then, wepropose an algorithm for reducing bias that we illustrate on these non-classical associated kernels. Some simulationsstudies are performed on three types of estimators lognormal kernels. Also, we study the asymptotic behavior of thecontinuous associated kernel estimators for density. We first show the pointwise weak and strong consistencies as wellas the asymptotic normality. Then, we present the results of the global weak and strong consistencies using uniform andL1norms. We illustrate this on three types of lognormal kernels estimators. Subsequently, we study the minimaxproperties of the continuous associated kernel estimators. We first describe the model and we give the technicalassumptions with which we work. Then we present our results that we apply on some non-classical associated kernelsmore precisely beta, gamma and lognormal kernel estimators. Finally, we combine continuous and discrete associatedkernels for defining the mixed associated kernels. Using the tools of the unification of discrete and continuous analysis,we show the different properties of the mixed associated kernel estimators. All through this work, we choose thesmoothing parameter using the least squares cross-validation method
Jung, Hyun Ju. "The generation and flow of knowledge in technology development." Diss., Georgia Institute of Technology, 2013. http://hdl.handle.net/1853/50296.
Full textŠimek, Milan. "Výběr referenčních uzlů pro bezkotevní lokalizační techniky v bezdrátových senzorových sítích." Doctoral thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2010. http://www.nusl.cz/ntk/nusl-233511.
Full textBotha, Christoffel Philippus. "The near field boundary of dewatering systems : estimating individual yields for wells operating under gravity flow." Thesis, University of Southampton, 2017. https://eprints.soton.ac.uk/416903/.
Full textWittebol, Laura. "Refinement and verification of the nocturnal boundary layer budget method for estimating greenhouse gas emissions from Eastern Canadian agricultural farms." Thesis, McGill University, 2009. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=66706.
Full textLes don nées sur les émissions des gaz à effet de serre (GES) obtenues au niveau des fermes entières agricoles sont pertinentes au secteur agricole et ont le potentiel d'éliminer une partie de l'incertitude qui se produit quant à l'extrapolation du niveau de la parcelle jusqu'au niveau du champ. La couche limite nocturne (CLN) agit comme une chambre virtuelle dans laquelle on fait plusieurs ascensions pour déterminer les fluxes de GES. Dans le but géneral de raffiner la méthode du budget de la CLN afin d'obtenir de plus fiables estimées au niveau de la ferme typique (environ 1 kilomètre carré), les fluxes de CO2, N2O, et CH4 ont été mesurés sur deux fermes agricoles dans l'est du Canada. En 1998 et 2002, les sites d'étude se trouvaient sur une ferme près d'une banlieue au sud-ouest d'Ottawa (Ontario), où le terrain est relativement plat et les principales cultures sont le maïs, le foin et le soya. En 2003, le site d'étude se situait dans la communauté rurale de Coteau-du-Lac (Québec), environ 20 km au sud-ouest de Montréal. Bordé par le fleuve St-Laurent au sud, ce terrain est plat et on y cultive surtout le maïs, le foin et un mélange de soya et de légumes. Le flux moyen de CO2 mesuré aux deux sites par la méthode du budget de la CLN correspondait bien avec celui mesuré par la technique de la covariance des fluctuations et aussi avec ce qui est rapporté dans la littérature. Considérant toutes les directions de vent et toutes les pratiques agricoles, la moyenne des flux de N2O mesurés par la technique de NBL était du même ordre de grandeur, quoiqu'un peu plus élevée, que ce qui est rapporté dans la littérature pour les émissions de base de N2O des écosystèmes agricoles. Les résultats pour le CH4 ont été jugés non-valides car l'échantillonage concurrente des trois gaz aux alentours des deux sites a confirmé que le CH4 était particulièrement sensible à la
Conti, Tatiana de. "Avaliação do método do balanço da camada limite para a estimativa de fluxos turbulentos noturnos." Universidade Federal de Santa Maria, 2006. http://repositorio.ufsm.br/handle/1/9203.
Full textEste trabalho trata de verificar o desempenho do método de balanço da camada limite como alternativa para a medição dos fluxos turbulentos superficiais em condições que permitem a validação das medidas com dados tomados a partir de uma torre equipada com sensores, os quais foram processados com o método de correlação de vórtices. É feita uma pesquisa do conhecimento gerado até o presente, que revela as limitações da sistemática de medição por correlação de vórtices e as promessas do método de balanço em relação à medição dos fluxos turbulentos. É descrita neste trabalho a fundamentação teórica necessária, a respeito do balanço energético na atmosfera e do papel da turbulência nos fenômenos de transporte e de troca de energia. Tais conceitos são interpretados fisicamente e descritos na forma de equações governantes e hipóteses utilizadas para a análise do comportamento de tais fenômenos. A correlação de vórtices é descrita como um método que mede diretamente os fluxos de calor sensível e de calor latente em função dos dados recolhidos pelos sensores. O método de balanço da camada limite, por sua vez é descrito a partir da formulação geral de acumulação de escalares, sobre a qual são tomadas as hipóteses de eliminação da advecção horizontal e de quaisquer fontes ou sumidouros na atmosfera. O contexto das medições é descrito a seguir, a partir da apresentação do projeto, dos locais, das campanhas e do dia e dos horários em que as medições foram realizadas. A instrumentação utilizada para a aquisição dos dados é também descrita, assim como a sistemática de processamento dos dados brutos. Os resultados obtidos revelam diferenças significativas na estimativa do fluxo de calor sensível, que aumentam com o avanço da noite e diferenças menores no fluxo de calor latente, que permanecem praticamente constantes no tempo.
Dinh, Van Duong. "Strichartz estimates and the nonlinear Schrödinger-type equations." Thesis, Toulouse 3, 2018. http://www.theses.fr/2018TOU30247/document.
Full textThis dissertation is devoted to the study of linear and nonlinear aspects of the Schrödinger-type equations [ i partial_t u + |nabla|^sigma u = F, quad |nabla| = sqrt {-Delta}, quad sigma in (0, infty).] When $sigma = 2$, it is the well-known Schrödinger equation arising in many physical contexts such as quantum mechanics, nonlinear optics, quantum field theory and Hartree-Fock theory. When $sigma in (0,2) backslash {1}$, it is the fractional Schrödinger equation, which was discovered by Laskin (see e.g. cite{Laskin2000} and cite{Laskin2002}) owing to the extension of the Feynman path integral, from the Brownian-like to Lévy-like quantum mechanical paths. This equation also appears in the water waves model (see e.g. cite{IonescuPusateri} and cite{Nguyen}). When $sigma = 1$, it is the half-wave equation which arises in water waves model (see cite{IonescuPusateri}) and in gravitational collapse (see cite{ElgartSchlein}, cite{FrohlichLenzmann}). When $sigma =4$, it is the fourth-order or biharmonic Schrödinger equation introduced by Karpman cite {Karpman} and by Karpman-Shagalov cite{KarpmanShagalov} taking into account the role of small fourth-order dispersion term in the propagation of intense laser beam in a bulk medium with Kerr nonlinearity. This thesis is divided into two parts. The first part studies Strichartz estimates for Schrödinger-type equations on manifolds including the flat Euclidean space, compact manifolds without boundary and asymptotically Euclidean manifolds. These Strichartz estimates are known to be useful in the study of nonlinear dispersive equation at low regularity. The second part concerns the study of nonlinear aspects such as local well-posedness, global well-posedness below the energy space and blowup of rough solutions for nonlinear Schrödinger-type equations.[...]
Petrovic, Milena. "Effects of the Object’s Mass and Distance on the Location of Preferred Critical Boundary, Discomfort, and Muscle Activation during a Seated Reaching Task." Miami University / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=miami1343567265.
Full textSomé, Sobom Matthieu. "Estimations non paramétriques par noyaux associés multivariés et applications." Thesis, Besançon, 2015. http://www.theses.fr/2015BESA2030/document.
Full textThis work is about nonparametric approach using multivariate mixed associated kernels for densities, probability mass functions and regressions estimation having supports partially or totally discrete and continuous. Some key aspects of kernel estimation using multivariate continuous (classical) and (discrete and continuous) univariate associated kernels are recalled. Problem of supports are also revised as well as a resolution of boundary effects for univariate associated kernels. The multivariate associated kernel is then defined and a construction by multivariate mode-dispersion method is provided. This leads to an illustration on the bivariate beta kernel with Sarmanov's correlation structure in continuous case. Properties of these estimators are studied, such as the bias, variances and mean squared errors. An algorithm for reducing the bias is proposed and illustrated on this bivariate beta kernel. Simulations studies and applications are then performed with bivariate beta kernel. Three types of bandwidth matrices, namely, full, Scott and diagonal are used. Furthermore, appropriated multiple associated kernels are used in a practical discriminant analysis task. These are the binomial, categorical, discrete triangular, gamma and beta. Thereafter, associated kernels with or without correlation structure are used in multiple regression. In addition to the previous univariate associated kernels, bivariate beta kernels with or without correlation structure are taken into account. Simulations studies show the performance of the choice of associated kernels with full or diagonal bandwidth matrices. Then, (discrete and continuous) associated kernels are combined to define mixed univariate associated kernels. Using the tools of unification of discrete and continuous analysis, the properties of the mixed associated kernel estimators are shown. This is followed by an R package, created in univariate case, for densities, probability mass functions and regressions estimations. Several smoothing parameter selections are implemented via an easy-to-use interface. Throughout the paper, bandwidth matrix selections are generally obtained using cross-validation and sometimes Bayesian methods. Finally, some additionnal informations on normalizing constants of associated kernel estimators are presented for densities or probability mass functions
Lovato, Rodrigo Gularte, and Rodrigo Gularte Lovato. "Estimativa da constante de Kolmogorov (C0) para a camada limite estável usando simulação dos grandes turbilhões." Universidade Federal de Pelotas, 2007. http://repositorio.ufpel.edu.br/handle/ri/2182.
Full textNeste trabalho, nós estimamos a constante de Kolmogorov, C01 através da determinação de um conjunto de trajetórias Lagrangeanas em uma Camada Limite Estável simulada pelo modelo de simulação dos grandes turbilhões (Large-Eddy Simulation model). A partir do conjunto de trajetórias, a forma da função de estrutura da velocidade Lagrangeana no subintervalo inercial é avaliada, permitindo a determinação de C0. O valor de C0 encontrado é 3,70.
Júnior, Rosiberto Salustiano da Silva. "Sensibilidade na estimativa da concentração de poluentes fotoquímicos com a aplicação de diferentes parametrizações de camada limite planetária utilizando o modelo de qualidade do ar WRF/Chem." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/14/14133/tde-23012010-102058/.
Full textThis work evaluated the parameterizations´ sensibility of the Planetary Boundary Layer (PBL) in the simulation of photochemical pollutants above the Metropolitan Region of São Paulo, by using the Weather Research and Forecasting (WRF) non-hydrostatic mesoscale model, with the coupling of chemical modules (WRF/Chem). In order to analyze the accuracy of the results obtained with the model, there will be used the measurements made by the automatic air quality stations from CETESB on surface, and the validation of the O3 vertical profile, will be based on ozonesoundings experiments conducted during the period of the study. The motivation for this study was the great difficulty in representing the PBLs structure specially during the night, witch is an new utilization of an on-line model to simulate the chemical composition of the atmosphere of the MASP, and finally, to analyze the impact of the coupling with the Urban Canopy Model (UCM). The study area is the Metropolitan Region of São Paulo and surroundings, and the period was between 10/28 11/01/2006. The annual variations of the air temperature, wind speed and solar radiation for 2006, showed that the month of October was marked by wide availability of solar radiation, high values of air temperature and intense winds. The simulations with idealized cases showed that the PBLs order of height based on the numerical scheme is YSU, MYJ, BOULAC and UCM, which influences directly the dispersion of pollutants with lower concentrations of the CO for YSU and higher for UCM respectively, and for the concentrations of the O3, the scheme YSU shows lower concentrations but unlike the CO, the other schemes are equal. However, for the simulations of real cases, the results showed a good correlation between simulated and observed for the surface concentrations of the O3 and CO, and a great difficulty of the model on the vertical profiles representation of the concentration of O3, when the 2.1 version of the WRF/Chem model is used. This problem was partially solved (can be better improved) when used with the latest version, as version 3, and coupled with the Urban Canopy Model. The experiments performed to estimate the impact of the land use type on the variation of the PBL height and consequent relationship with the chemical composition of the atmosphere, showed that the PBL height is higher on the urban areas compared to rural areas, thus influencing effectively in the dispersal of pollutants, and a lower PBL height was associated with higher concentrations due to lower dispersion of pollutants. This work has demonstrated the transport of pollutants between the metropolitan regions of São Paulo - Campinas and São Paulo - Sorocaba, due to topography that acts targeting the wind in the direction of Campinas. The proximity of emission sources has been important for the level of concentration of O3, as it moves away from sources of emissions both vertically and horizontally increases its concentration. Due the proximity with the Atlantic Ocean, the formation of Sea Breeze helps dispersion of pollutants emitted and formed in the MASP.
Brondani, Daiane de Vargas. "ESTIMATIVA DA PARTIÇÃO DE ENERGIA NA SUPERFÍCIE A PARTIR DE SÉRIES METEOROLÓGICAS DE TEMPERATURA E UMIDADE ESPECÍFICA DO AR." Universidade Federal de Santa Maria, 2015. http://repositorio.ufsm.br/handle/1/10285.
Full textThe developed method is proposed with the aim of estimating the energy partition on the surface, according to the Bowen ratio method, and the height of convective boundary layer on the monthly scale. The basic hypothesis is that the average temporal evolution of the variables air temperature and specific humidity is controlled solely by the convergence of surface fluxes of sensible and latent heat. This assumption is valid for the monthly scale and in mid-latitude regions away from the coast. Thus, it is assumed that the advective terms of the balance equation of these quantities in the convective boundary layer in prefrontal and post-frontal situations have opposite sign. Therefore, using for a longer time scale than the typical scale of the passage of synoptic systems, the cancellation of terms hypothesis can be tested. In this study, the method is applied to the region of Santa Maria, where it is assumed that the conditions allowing despise the advective terms in a monthly time scale are valid. Although the model is simplified, it was possible to estimate the surface fluxes of latent and sensible heat from simple meteorological data, such as hourly observations of air temperature and specific humidity and a vertical profile of these quantities in the morning; the method was efficient in most of the cases, and more flawed in the winter months. In general, the method overestimated consistently, but slightly, the latent heat fluxes, while the sensible heat fluxes were slightly underestimated in the winter and overestimated in the remaining months. This pattern caused a major deviation in energy partition in the winter months. The method can also be used to provide time evolution of the convective boundary layer. This is a variable of great interest for studies of pollutant dispersion and in many cases it is difficult to estimate.
O método desenvolvido é proposto com as finalidades de estimar a partição de energia na superfície pelo método da razão de Bowen e a altura da camada limite convectiva na escala mensal. A hipótese básica é de que a evolução temporal média das variáveis temperatura e umidade específica do ar é controlada unicamente pela convergência dos fluxos superficiais de calor sensível e calor latente. Essa suposição é válida para escala mensal e em regiões de latitudes médias afastadas da costa. Dessa forma, presume-se que os termos advectivos, da equação de balanço dessas quantidades na camada limite convectiva, nas situações pré-frontais e pós-frontais apresentam sinal oposto. Assim, utilizando-se para uma escala temporal mais longa que a escala típica da passagem dos sistemas sinóticos, a hipótese de cancelamento dos termos pode ser testada. No presente trabalho, o método é aplicado para a região de Santa Maria, onde é assumido que as condições que permitem desprezar os termos advectivos em escala mensal são válidas. Ainda que o modelo apresentado esteja simplificado, foi possível estimar os fluxos superficiais de calor latente e sensível a partir de dados meteorológicos simples, como observações horárias de temperatura do ar e umidade específica e um perfil vertical dessas quantidades no período da manhã; o método se mostrou eficiente em boa parte dos casos, sendo mais falho nos meses de inverno. De modo geral, o método superestimou consistentemente, mas de maneira leve, os fluxos de calor latente, enquanto os fluxos de calor sensível foram levemente subestimados no inverno e superestimados nos demais meses. Esse padrão causou um maior desvio na partição de energia nos meses de inverno. O método também pode ser utilizado para fornecer a evolução da altura da camada limite convectiva. Esta é uma variável de grande interesse para estudos de dispersão de poluentes e, em muitos casos, de difícil estimativa.