Dissertations / Theses on the topic 'GEC Models'
To see the other types of publications on this topic, follow the link: GEC Models.
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 'GEC Models.'
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.
1
Pedersen, Michael. "Modular languages for systems and synthetic biology." Thesis, University of Edinburgh, 2010. http://hdl.handle.net/1842/4602.
Full textAbstract:
Systems biology is a rapidly growing field which seeks a refined quantitative understanding of organisms, particularly studying how molecular species such as metabolites, proteins and genes interact in cells to form the complex emerging behaviour exhibited by living systems. Synthetic biology is a related and emerging field which seeks to engineer new organisms for practical purposes. Both fields can benefit from formal languages for modelling, simulation and analysis. In systems biology there is however a trade-off in the landscape of existing formal languages: some are modular but may be difficult for some biologists to understand (e.g. process calculi) while others are more intuitive but monolithic (e.g. rule-based languages). The first major contribution of this thesis is to bridge this gap with a Language for Biochemical Systems (LBS). LBS is based on the modular Calculus of Biochemical Systems and adds e.g. parameterised modules with subtyping and a notion of nondeterminism for handling combinatorial explosion. LBS can also incorporate other rule-based languages such as Kappa, hence adding modularity to these. Modularity is important for a rational structuring of models but can also be exploited in analysis as is shown for the specific case of Petri net flows. On the synthetic biology side, none of the few existing dedicated languages allow for a high-level description of designs that can be automatically translated into DNA sequences for implementation in living cells. The second major contribution of this thesis is exactly such a language for Genetic Engineering of Cells (GEC). GEC exploits the recent advent of standard genetic parts (“biobricks”) and allows for the composition of such parts into genes in a modular and abstract manner using logical constraints. GEC programs can then be translated to DNA sequences using a constraint satisfaction engine based on a given database of genetic parts.
2
Zhai, Menghua. "Deep Probabilistic Models for Camera Geo-Calibration." UKnowledge, 2018. https://uknowledge.uky.edu/cs_etds/74.
Full textAbstract:
The ultimate goal of image understanding is to transfer visual images into numerical or symbolic descriptions of the scene that are helpful for decision making. Knowing when, where, and in which direction a picture was taken, the task of geo-calibration makes it possible to use imagery to understand the world and how it changes in time. Current models for geo-calibration are mostly deterministic, which in many cases fails to model the inherent uncertainties when the image content is ambiguous. Furthermore, without a proper modeling of the uncertainty, subsequent processing can yield overly confident predictions. To address these limitations, we propose a probabilistic model for camera geo-calibration using deep neural networks. While our primary contribution is geo-calibration, we also show that learning to geo-calibrate a camera allows us to implicitly learn to understand the content of the scene.
3
Corr?a, F?bio Mathias. "Metodologia de avalia??o da requeima e sele??o de gen?tipos de tomate resistentes a Phytophthora infestans (Mont) de Bary." Universidade Federal Rural do Rio de Janeiro, 2008. https://tede.ufrrj.br/jspui/handle/tede/525.
Full textAbstract:
Made available in DSpace on 2016-04-28T14:58:36Z (GMT). No. of bitstreams: 1
2008 - Fabio Mathias Correa.pdf: 2421517 bytes, checksum: 7f7f9e77fc6d68db6e05dbd9994c1e38 (MD5)
Previous issue date: 2008-02-28Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico
The late blight of the tomato, caused by Phytophthora infestans (Mont) of Bary it is one of the main diseases of the tomato. However, the quantification of the severity of the disease, doesn't possess a standard method of evaluation and that, it can interfere in the comparison of results among and inside of experiments, once the scale of evaluation of the disease should be standardized. A diagrammatic scale should represent all variation of the existent disease in the field and to make possible necessary evaluations and perfected, independent of the existent differences among appraisers. Another important factor in the epidemiological studys, is the correct application of the methodologies of evaluation of treatments or cultivars. Therefore, the present work has as objectives: 1) to develop and to validate a diagrammatic scale for quantification of the severity of the late blight in tomateiro leaves and 2) to compare the use of AUDPC (area under disease progress curve), certain according to Shanner & Finney (1977), with the use of mixed models and mixed lineal models widespread in the selection of gen?tipos of resistant tomateiro to the requeima. Three diagrammatics scales were proposed for evaluation of the late blight in tomato leaves. The first scale, denominated scale-detailed, it was composed by nine values of severity intensity (0, 3, 6, 12, 22, 40, 60, 77 and 90%), the second climb, call of having scale-simplified, it was composed by seven severity values (0, 3, 12, 22, 40, 60 and 77%) and the third scale, of having James-modified, composed by seven severity values (0, 1, 5, 10, 16, 32 and 50%). For the validation of the scales, 24 appraisers accomplished two evaluations in leaves 50 tomato leaves with different severity levels, where the precision, acuracy and repetibility were appraised through simple lineal regression, analysis of variance of the mistakes and correlation coefficient. Among the proposed scales, two came as tools that allow a good precision and acuracy in the evaluation of the severity of the late blight in tomato leaves, being the detailed scale and the simplified scale. With relationship to the analysis methods, the use of direct AACPD, calculated by the sum of Riemann, and of mixed and mixed models widespread, it was verified that the direct use of AUDPC, doesn't get to describe all existent variation in the sample, probably for the great number of treatments. The use of mixed models widespread, that it considers the distribution of Poisson, it was shown more appropriate for to describe the epidemic caused by late blight in tomato, being more suitable in the selection of tomato cultivars seeking to the resistance the this disease.
A requeima, causada por Phytophthora infestans ? uma das principais doen?as do tomateiro. Para quantificar a severidade da doen?a, n?o h? um m?todo padr?o, o que pode interferir na compara??o de resultados entre e dentro de experimentos, uma vez que a escala de avalia??o da doen?a deve ser padronizada. Uma escala diagram?tica deve representar toda a varia??o da severidade no campo e possibilitar avalia??es precisas e acuradas, independente das diferen?as entre avaliadores. Outro fator importante no estudo epidemiol?gico ? a correta aplica??o das metodologias de avalia??o de tratamentos ou gen?tipos. Portanto, o presente trabalho objetivou: 1) desenvolver e validar uma escala diagram?tica para quantifica??o da severidade da requeima em folhas de tomateiro e 2) comparar o uso da ?rea abaixo da curva de progresso da doen?a (AACPD), com o uso de modelos mistos e modelos lineares mistos generalizados na sele??o de gen?tipos de tomateiro resistentes ? requeima. Tr?s escalas diagram?ticas foram propostas para avalia?ar a requeima em folhas de tomateiro. A primeira, denominada escala-detalhada, foi composta por nove valores de intensidade de severidade (0, 3, 6, 12, 22, 40, 60, 77 e 90%). A segunda escala, chamada de escala-simplificada, foi composta por sete valores de severidade (0, 3, 12, 22, 40, 60 e 77%) e a terceira, de Jamesmodificada, composta por sete valores de severidade (0, 1, 5, 10, 16, 32 e 50%). Para a valida??o das escalas, 24 avaliadores realizaram duas avalia??es em 50 folhas de tomateiro com diferentes n?veis de severidade, e a precis?o, acur?cia e a repetibilidade dos avaliadores foram avaliados atrav?s de regress?o linear simples, an?lise de vari?ncia dos erros e coeficiente de correla??o de Pearson. Dentre as escalas propostas, duas (escala detalhada e escala simplificada) apresentaram uma boa precis?o e acur?cia para a avalia??o da severidade da requeima em folhas de tomateiro. Quanto aos m?todos de an?lise, constatou-se que o uso direto da AACPD, obtido pela soma de Riemann, n?o conseguiu descrever toda varia??o existente na amostra, provavelmente pelo grande n?mero de tratamentos. O uso de modelos mistos generalizados, que considera a distribui??o de Poisson, foi mais adequado para descrever a epidemia, sendo mais indicado na sele??o de gen?tipos de tomate resistentes a doen?a.
4
Betrabet, Chinmay Suresh. "Inorganic-organic hybrid materials and abrasion resistant coatings based on a sol-gel approach." Diss., Virginia Tech, 1993. http://hdl.handle.net/10919/40188.
Full textAbstract:
Novel inorganic-organic hybrid materials made previously in the laboratory have
utilized acids catalysts such as HCI, acetic acid, toluene sulfonic acid and polystyrene sulfonic acid to catalyze the sol-gel reaction. The sol-gel reaction can also be catalyzed under near neutral (i.e. 5 < pH < 7) and basic conditions. The effects of synthesizing hybrid materials under near basic and basic conditions has not been studied.
Attempts to synthesize hybrid materials from polytetramethylene oxide (PTMO) end functionalized with triethoxy silyl groups and, tetraethylorthosilicate (TEOS) under basic conditions met with only partial success. The films obtained had low mechanical stability. This was attributed to the low reactivity of the triethoxy species under neutral and basic conditions. In contrast, films with good mechanical stability were obtained when the TEOS was replaced with titanium tetraisopropoxide (TIOPR). The microstructure of the TIOPRlPTMO hybrid synthesized under near neutral conditions was generally similar to the acid catalyzed PTMOffIOPR hybrids.Ph. D.
5
Chung, Hyoju. "GEE with large cluster sizes : high-dimensional working correlation models /." Thesis, Connect to this title online; UW restricted, 2006. http://hdl.handle.net/1773/9545.
Full text
6
Keogh, Andrew James, University of Western Sydney, of Science Technology and Environment College, and School of Engineering and Industrial Design. "Geo-chemical budget models of the Penrith Lakes Scheme." THESIS_CSTE_EID_Keogh_A.xml, 2003. http://handle.uws.edu.au:8081/1959.7/472.
Full textAbstract:
The Penrith Lakes Scheme is a series of inter-connected lakes, produced by the rehabilitation of a sand and gravel quarry, for water quality treatment and recreational uses. Presently, 5 lakes are operational comprising 4 upstream lakes for treatment of storm-water and quarry discharge and a single downstream recreational lake as the Sydney International Regatta Centre used during the Sydney 2000 Olympic Games. This report is the result of a study, during 1998-2003, with an aim to develop dynamic budget models of water, sediments and nutrients for these lakes, providing suitable data for long-term management planning and evaluation of short-term operational management.Findings showed that while progressive reassessment and refinement will be required as management control increases, the approach provides the foundation modelling procedures and frame-work for suitable hydrological and water quality management of the Penrith Lakes Scheme, and may be extended to include further lakes, water sources and management strategies.Doctor of Philosophy (PhD)
7
Keogh, Andrew James. "Geo-chemical budget models of the Penrith Lakes Scheme /." View thesis, 2003. http://library.uws.edu.au/adt-NUWS/public/adt-NUWS20040528.121937/index.html.
Full textAbstract:
Thesis (Ph. D.)--University of Western Sydney, 2003."A thesis submitted to the School of Engineering and Industrial Design, University of Western Sydney, in partial fulfilment of the requirements of the degree of Doctor of Philosophy." Includes bibliographical references and appendices.
8
Lee, Woojin. "Polymer gel based actuator : dynamic model of gel for real time control." Thesis, Massachusetts Institute of Technology, 1996. http://hdl.handle.net/1721.1/10939.
Full text
9
McSweeny, Andrew. "Genome Evolution Model (GEM): Design and Application." University of Toledo Health Science Campus / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=mco1290550446.
Full text
10
Costa, João Pedro Tavares Pereira da. "Caracterização de serviços de Internet geo-replicados." Master's thesis, Faculdade de Ciências e Tecnologia, 2013. http://hdl.handle.net/10362/11881.
Full textAbstract:
Dissertação para obtenção do Grau de Mestre em
Engenharia InformáticaCom o aumento da popularidade de serviços distribuídos que recorrem à geo-replicação, a comunidade científica tem efectuado um esforço activo para desenvolver modelos de consistência e esquemas de replicação, que permitam a estas aplicações encontrar um equilíbrio adequado entre desempenho e a exposição da camada de replicação para os utilizadores destas aplicações. No entanto, é pouco claro quais os modelos de consistência que são oferecidos por aplicações reais e extremamente populares, como por exemplo o Facebook ou o Twitter. Nesta tese é proposta uma metodologia e é descrita uma arquitectura que pretende validar um conjunto de propriedades relevantes relativas ao modelo de consistência oferecido por aplicações reais de grande escala. Em particular a nossa abordagem permite verificar violações de propriedades de sessão bem conhecidas, assim como verificar se a causalidade entre os efeitos das operações observados pelos utilizadores é violada. Adicionalmente, a nossa abordagem tenta também inferir a janela de divergência observada pelos clientes. Desta forma consegue-se observar que garantias de consistência são respeitadas por um serviço distribuído sem que seja necessário ter conhecimento sobre o seu funcionamento interno, permitindo construindo melhores modelos de consistência. Esta metodologia serve ainda como uma ferramenta auxiliar no desenvolvimento de um serviço distribuído, permitindo verificar se este oferece o modelo de consistência esperado.
11
Cutler, Barbara M. (Barbara Mary) 1975. "Aggregating building fragments generated from geo-referenced imagery into urban models." Thesis, Massachusetts Institute of Technology, 1999. http://hdl.handle.net/1721.1/80525.
Full textAbstract:
Thesis (M.Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1999.Includes bibliographical references (p. 113-115).
Barbara M. Cutler.
M.Eng.
12
Lombardi, Anna Maria <1973>. "Development and application of stochastic models of earthquake occurrence." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2007. http://amsdottorato.unibo.it/357/1/tesi_Lombardi.pdf.
Full text
13
Lombardi, Anna Maria <1973>. "Development and application of stochastic models of earthquake occurrence." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2007. http://amsdottorato.unibo.it/357/.
Full text
14
Magni, Valentina <1984>. "Numerical models of trench migration for lateral heterogeneous subducting plates." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2012. http://amsdottorato.unibo.it/4280/1/magni_valentina_tesi.pdf.
Full textAbstract:
The aim of this Thesis is to investigate the effect of heterogeneities within the subducting plate on the dynamics of subduction. In particular, I study the motion of the trench for oceanic and continental subduction, first, separately, and, then, together in the same system to understand how they interact. The understanding of these features is fundamental to reconstruct the evolution of complex subduction zones, such as the Central Mediterranean.
For this purpose, I developed 2D and 3D numerical models of oceanic and continental subduction where the rheological, geometrical and compositional properties of the plates are varied. In these models, the trench and the overriding plate move self-consistently as a function of the dynamics of the system.
The effect of continental subduction on trench migration is largely investigated. Results from a parametric study showed that despite different rheological properties of the plates, all models with a uniform continental crust share the same kinematic behaviour: the trench starts to advance once the continent arrives at the subduction zone. Hence, the advancing mode in continental collision scenarios is at least partly driven by an intrinsic feature of the system. Moreover, the presence of a weak lower crust within the continental plate can lead to the occurrence of delamination. Indeed, by changing the viscosity of the lower crust, both delamination and slab detachment can occur. Delamination is favoured by a low viscosity value of the lower crust, because this makes the mechanical decoupling easier between crust and lithospheric mantle. These features are observed both in 2D and 3D models, but the numerical results of the 3D models also showed that the rheology of the continental crust has a very strong effect on the dynamics of the whole system, since it influences not only the continental part of plate but also the oceanic sides.
15
Magni, Valentina <1984>. "Numerical models of trench migration for lateral heterogeneous subducting plates." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2012. http://amsdottorato.unibo.it/4280/.
Full textAbstract:
The aim of this Thesis is to investigate the effect of heterogeneities within the subducting plate on the dynamics of subduction. In particular, I study the motion of the trench for oceanic and continental subduction, first, separately, and, then, together in the same system to understand how they interact. The understanding of these features is fundamental to reconstruct the evolution of complex subduction zones, such as the Central Mediterranean.
For this purpose, I developed 2D and 3D numerical models of oceanic and continental subduction where the rheological, geometrical and compositional properties of the plates are varied. In these models, the trench and the overriding plate move self-consistently as a function of the dynamics of the system.
The effect of continental subduction on trench migration is largely investigated. Results from a parametric study showed that despite different rheological properties of the plates, all models with a uniform continental crust share the same kinematic behaviour: the trench starts to advance once the continent arrives at the subduction zone. Hence, the advancing mode in continental collision scenarios is at least partly driven by an intrinsic feature of the system. Moreover, the presence of a weak lower crust within the continental plate can lead to the occurrence of delamination. Indeed, by changing the viscosity of the lower crust, both delamination and slab detachment can occur. Delamination is favoured by a low viscosity value of the lower crust, because this makes the mechanical decoupling easier between crust and lithospheric mantle. These features are observed both in 2D and 3D models, but the numerical results of the 3D models also showed that the rheology of the continental crust has a very strong effect on the dynamics of the whole system, since it influences not only the continental part of plate but also the oceanic sides.
16
Tur, Mongé Inma 1985. "Mapping eQTL networks with mixed graphical models." Doctoral thesis, Universitat Pompeu Fabra, 2014. http://hdl.handle.net/10803/145479.
Full textAbstract:
Expression quantitative trait loci (eQTL) mapping constitutes a challenging problem
due to the high-dimensional multivariate nature of continuous gene expression traits and
discrete genotypes from genetical genomics experiments.
Next to the expression heterogeneity produced by confounding factors and other
sources of unwanted variation, indirect e ects spread throughout genes as a result of
genetic, molecular and environmental perturbations. Disentangling direct from indirect
e ects while adjusting for unwanted variability should help us moving from current parts
list of molecular components to understanding how these components work together in
networks of eQTL and gene to gene associations.
There is a large body of statistical methodology to tackle this challenge within the
context of linear models for continuous data. However, little has been investigated in using
graphical Markov models (GMMs) and conditional independence on mixed continuous
and discrete data from genetical genomics data sets, which are powerful tools for the
analysis of complex associations.
In this thesis we investigate the use of mixed GMMs to estimate eQTL networks from
data. We develop procedures to simulate these models and data from them to gather
insight into the propagation of additive e ects throughout the network. We derive the
parameters for a likelihood ratio exact test that enables use of higher-order conditional
independence with mixed GMMs. We exploit this test in the context of limited-order
correlations and marginal distributions to obtain estimates of the underlying eQTL net-
work. We show in the context of a yeast genetical genomics data set, that this estimate
leads to a sparser network with more direct associations that provide valuable insight into
the genetic control of gene expression in yeast. We develop an algorithm for accurate es-
timation of the genetic e ects of eQTLs in the presence of missing data. All algorithms
described in this thesis are implemented in the R/Bioconductor package qpgraph.La cartogra a gen etica dels trets quantitatius d'expressi o (eQTL) esdev e un gran repte degut a la naturalesa multivariant d'alta dimensionalitat dels trets continus d'expressi o g enica i els genotips discrets dels experiments de gen omica gen etica. A m es de l'heterogene tat de l'expressi o produ da pels factors de confusi o i altres fonts de variabilitat no desitjada, els efectes indirectes s'estenen per tots els gens com a resultat de perturbacions gen etiques, moleculars i ambientals. L'identi caci o d'efectes directes tot ajustant pels efectes de variabilitat no desitjada, ens hauria de permetre entendre com els diferents components moleculars interaccionen en xarxes d'associacions entre eQTLs i gens. Per abordar aquest problema, existeixen nombrosos m etodes estad stics en el context dels models lineals per a dades cont nues. En canvi, els models gr a cs de Markov (GMMs) i la independ encia condicional, tot i que s on eines adients per a l'estudi d'associacions complexes, han estat poc investigades en el context de dades mixtes cont nues i discretes de gen omica gen etica. En aquesta tesi, investiguem l' us dels GMMs mixtes per a estimar xarxes d'eQTLs. Desenvolupem procediments per a simular GMMs mixtes i simular dades a partir d'aquests models per tal d'investigar la propagaci o dels efectes additius a trav es de la xarxa. Derivem els par ametres d'un test de versemblan ca exacte que ens permet utilitzar independ encies condicionals d'ordre gran amb els GMMs mixtes. Utilitzem aquest test en el context de correlacions d'ordre limitat i distribucions marginals per a obtenir estimacions de la xarxa d'eQTLs subjacent. Tamb e mostrem que, en el context d'un conjunt de dades de gen omica gen etica de llevat, aquesta estimaci o d ona lloc a una xarxa esparsa amb associacions m es directes que ens proporcionen informaci o rellevant sobre el control gen etic de l'expressi o dels gens en llevat. Desenvolupem un algoritme per estimar de manera acurada els efectes gen etics dels eQTLs a partir de dades missing. Tots els algoritmes descrits en aquesta tesi estan implementats en el paquet de R/Bioconductor qpgraph.
17
Lorenzano, Emanuele <1989>. "Discrete fault models: the dynamical role of asperities and their interaction." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2018. http://amsdottorato.unibo.it/8463/1/Lorenzano_Emanuele_tesi.pdf.
Full textAbstract:
The present thesis focuses on the mechanics of the seismic source, in the framework of asperity models of faults. Thanks to the major role played by asperities in the dynamics of the seismic source, faults have been treated as dynamical systems made of a small number of asperities, weak regions or fault segments. The state of the system is described by the slip deficits or Coulomb stresses associated with the regions of the fault. Five cases are illustrated, differing for the number of asperities, weak regions or fault segments and for the mechanical processes investigated. In a model of a fault with a single asperity, the dynamics is described by two dynamic modes, corresponding to asperity loading and asperity failure, respectively. In a model of a fault with an asperity and a weak region, the dynamics is studied in terms of three dynamic modes, corresponding to interseismic intervals, seismic slip of the asperity and afterslip in the weak region. In a model of a two-asperity fault with purely elastic coupling, the dynamics is described by a sticking mode, associated with stationary asperities, and three slipping modes, corresponding to the slip of one or both asperities at a time. If viscoelastic coupling between the asperities is assumed, the model allows to highlight the role of rock rheology in the duration of the interseismic intervals of the fault and in the response to stress perturbations from neighbouring faults. In a model of a system of n faults generating a seismic sequence, it is possible to retrieve the state of the system at any time during the sequence. Also, the order of fault activation is described by a permutation of the first n natural numbers. In each case, applications to real faults are presented.
18
Cirella, Antonella <1977>. "Joint inversion of GPS and strong motion data for earthquake rupture models." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2008. http://amsdottorato.unibo.it/865/1/Tesi_Cirella_Antonella.pdf.
Full text
19
Cirella, Antonella <1977>. "Joint inversion of GPS and strong motion data for earthquake rupture models." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2008. http://amsdottorato.unibo.it/865/.
Full text
20
Colombelli, Simona <1986>. "Early Warning For Large Earthquakes: Observations, Models and Real-Time Data Analysis." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2014. http://amsdottorato.unibo.it/6339/1/colombelli_simona_tesi.pdf.
Full textAbstract:
This thesis is a collection of works focused on the topic of Earthquake Early Warning, with a special attention to large magnitude events. The topic is addressed from different points of view and the structure of the thesis reflects the variety of the aspects which have been analyzed. The first part is dedicated to the giant, 2011 Tohoku-Oki earthquake. The main features of the rupture process are first discussed. The earthquake is then used as a case study to test the feasibility Early Warning methodologies for very large events. Limitations of the standard approaches for large events arise in this chapter. The difficulties are related to the real-time magnitude estimate from the first few seconds of recorded signal. An evolutionary strategy for the real-time magnitude estimate is proposed and applied to the single Tohoku-Oki earthquake.
In the second part of the thesis a larger number of earthquakes is analyzed, including small, moderate and large events. Starting from the measurement of two Early Warning parameters, the behavior of small and large earthquakes in the initial portion of recorded signals is investigated. The aim is to understand whether small and large earthquakes can be distinguished from the initial stage of their rupture process. A physical model and a plausible interpretation to justify the observations are proposed.
The third part of the thesis is focused on practical, real-time approaches for the rapid identification of the potentially damaged zone during a seismic event. Two different approaches for the rapid prediction of the damage area are proposed and tested. The first one is a threshold-based method which uses traditional seismic data. Then an innovative approach using continuous, GPS data is explored. Both strategies improve the prediction of large scale effects of strong earthquakes.
21
Colombelli, Simona <1986>. "Early Warning For Large Earthquakes: Observations, Models and Real-Time Data Analysis." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2014. http://amsdottorato.unibo.it/6339/.
Full textAbstract:
This thesis is a collection of works focused on the topic of Earthquake Early Warning, with a special attention to large magnitude events. The topic is addressed from different points of view and the structure of the thesis reflects the variety of the aspects which have been analyzed. The first part is dedicated to the giant, 2011 Tohoku-Oki earthquake. The main features of the rupture process are first discussed. The earthquake is then used as a case study to test the feasibility Early Warning methodologies for very large events. Limitations of the standard approaches for large events arise in this chapter. The difficulties are related to the real-time magnitude estimate from the first few seconds of recorded signal. An evolutionary strategy for the real-time magnitude estimate is proposed and applied to the single Tohoku-Oki earthquake.
In the second part of the thesis a larger number of earthquakes is analyzed, including small, moderate and large events. Starting from the measurement of two Early Warning parameters, the behavior of small and large earthquakes in the initial portion of recorded signals is investigated. The aim is to understand whether small and large earthquakes can be distinguished from the initial stage of their rupture process. A physical model and a plausible interpretation to justify the observations are proposed.
The third part of the thesis is focused on practical, real-time approaches for the rapid identification of the potentially damaged zone during a seismic event. Two different approaches for the rapid prediction of the damage area are proposed and tested. The first one is a threshold-based method which uses traditional seismic data. Then an innovative approach using continuous, GPS data is explored. Both strategies improve the prediction of large scale effects of strong earthquakes.
22
Adnan, Rohana. "Theoretical studies and structural analysis of models of surface organometallic centres." Thesis, University of Southampton, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.327328.
Full text
23
Schreiber, Jonah. "Tracking Online Trend Locations using a Geo-Aware Topic Model." Thesis, KTH, Skolan för datavetenskap och kommunikation (CSC), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-190887.
Full textAbstract:
In automatically categorizing massive corpora of text, various topic models have been applied with good success. Much work has been done on applying machine learning and NLP methods on Internet media, such as Twitter, to survey online discussion. However, less focus has been placed on studying how geographical locations discussed in online fora evolve over time, and even less on associating such location trends with topics. Can online discussions be geographically tracked over time? This thesis attempts to answer this question by evaluating a geo-aware Streaming Latent Dirichlet Allocation (SLDA) implementation which can recognize location terms in text. We show how the model can predict time-dependent locations of the 2016 American primaries by automatic discovery of election topics in various Twitter corpora, and deduce locations over time.
24
Gruenwald, Edward. "A geo-spatial interpretive planning model for Illinois state parks /." Available to subscribers only, 2005. http://proquest.umi.com/pqdweb?did=1079664451&sid=29&Fmt=2&clientId=1509&RQT=309&VName=PQD.
Full text
25
Fornaciai, Alessandro <1974>. "Morphometric Analysis of Mount Etna Lava Flows Using High Resolution Digital Elevation Models." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2017. http://amsdottorato.unibo.it/7847/1/Alessandro_Fornaciai_Tesi.pdf.
Full textAbstract:
Morphometric analysis of lava flows provides crucial information for a better understanding of the processes of lava flow dynamics and emplacement. In this thesis, high-resolution DEMs obtained by the airborne LiDAR system and the UAV-SfM system are used for an extensive morphometric analysis of the Mount Etna (Italy) lava flow. A digital comparison of pre- and post-eruptive LiDAR DEMs of Etna was made to quantify the lava volumes emitted in the 2004-2005, 2005-2006 and 2007-2010 intervals. The erupted volume of 2004-2005 is ~63.3 × 106 m3 entirely emitted by the 2004-05 eruption. The erupted volume of 2005-2007 is ~ 42.0 × 106 m3, of which ~33.5 × 106 m3 emitted by the September-December 2006 eruption. The erupted volume of 2007-2010 is >86 × 106m3, most of which (~74 × 106m3) is formed by the lava flows of the 2008-2009 flank eruption. Lava flow morphometric analysis was performed over LiDAR DEM for eleven channel-fed lava flows through a semi-automatic procedure and using SVF and openness down parameters to better detect and delimit surface-specific elements, i.e. lava levees, base and channel-bed. The results show an inverse relation between slope and channel width, a certain coherence between average slope of levees and pre-emplacing slope, and the same trend between the channel width and channel-bed width. Finally, in order to investigate less costly methods for producing DEMs, we created a high-resolution DEM of the 1974 lava flow using the UAV-SfM system and then we compared it with the LiDAR-derived DEM. The UAV-SfM system can be effectively used to produce topographic data for large areas with an accuracy and resolution that are even higher than those of the LiDAR system. Therefore, the UAV-SfM system can be effectively used to update the topography of active volcanic areas with reasonable costs and short time of deployment.
26
Tang, Zhongwen. "LOF of logistic GEE models and cost efficient Bayesian optimal designs for nonlinear combinations of parameters in nonlinear regression models." Diss., Manhattan, Kan. : Kansas State University, 2008. http://hdl.handle.net/2097/1011.
Full text
27
Shen, Wei <1993>. "Numerical simulation of rapid flow-like landslides and some related phenomena based on improved depth-averaged models." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2022. http://amsdottorato.unibo.it/10023/1/PhD_thesis_Wei_SHEN_10-01-2022.pdf.
Full textAbstract:
Numerical simulation is an efficient tool for the run-out analysis of rapid flow-like landslide. In this thesis, I address three topics related to the modeling of flow-like landslide which were not sufficiently investigated in the previous studies. Three improved depth-averaged models are used to simulate the selected typical flow-like landslides and related phenomena. In the first topic, a two-layer depth-averaged model is proposed to simulate the frontal plowing phenomenon in some rapid flow-like landslides. The propagation process of a loess landslide in Shaanxi Province, China and its interaction with the terrace material is analyzed. The second topic is related to the influence of the slope gradient and gully channel on the run-out behavior (especially the entrainment and deposition characteristics) of rockslide-debris flow. The run-out process of the Verghereto landslide in Italy is analyzed by using an improved depth-averaged model. The third topic is related to the numerical assessment of the impeding effect of check dam on debris flow. Another improved depth-averaged model, which takes both entrainment and the impeding effect of check dam into account, is proposed and adopted to analyze the interaction of debris flow and check dams in a debris flow gully in Sichuan province, China. The model is then used to assess the efficiency of the actual check dams in this debris flow gully. The main purpose of this thesis is to investigate the capacity of the improved depth-averaged models on the simulation of rapid flow-like landslides and the related phenomena (frontal plowing, entrainment, and interaction between debris flow and check dam). The simulation results of the case studies in this thesis show that these improved models perform well in simulating the rapid flow-like landslides and the phenomena mentioned above, which demonstrates the potential application ability of these models for the risk assessment of rapid flow-like landslides.
28
Passarelli, Luigi <1981>. "A new statistical model for eruption forecasting." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2010. http://amsdottorato.unibo.it/2824/1/tesi_dottorato_geofisica_Luigi_Passarelli.pdf.
Full text
29
Passarelli, Luigi <1981>. "A new statistical model for eruption forecasting." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2010. http://amsdottorato.unibo.it/2824/.
Full text
30
MEMMOLA, FRANCESCO. "Analysis and Development of Oceanographic Models: reaching the Swash Zone." Doctoral thesis, Università Politecnica delle Marche, 2017. http://hdl.handle.net/11566/245612.
Full textAbstract:
Analisi e sviluppo di modelli oceanografici: per
raggiungere la zona di battigia
La battigia è la parte della spiaggia dove la dissipazione finale delll’energia
delle onde di solito si verifica, mentre l’energia delle onde a bassa frequenza
è, generalmente, riflessa verso mare. Inoltre, avviene anche la generazione e
la riflessione di ulteriori onde a bassa frequenza. I flussi nella zona di bat-
tigia sono di fondamentale importanza non solo per i loro effetti locali ma
anche perché possono influenzare la dinamica di tutta la zona costiera. No-
nostante la sua importanza, i tipici modelli di circolazione non tengono conto
della dinamica della zona di battigia e al contorno di riva vengono applicate
condizioni semplificate. Spesso queste condizioni sono prevedono il totale
assorbimento o la perfetta riflessione delle onde incidenti (parete rigida), al
confine verso costa del dominio computazionale. Tuttavia, all’interno di una
zona di battigia infinitesimale nessuna generazione o modifica di onde a bas-
sa frequenza può verificarsi e tutte le onde in arrivo a bassa frequenza sono
riflesse in un unico punto. Con questo contributo si esplora la possibilità
di implementare in solutori di tipo wave-averaged , un modello teorico che
tiene pienamente conto, attraverso un approccio integrale, delle dinamiche
zona di battigia. Una volta che tale modello è implementato, il risolutore
wave-averaged sarà in grado di calcolare la posizione della linea di riva e di
fornire lungo questa le principali proprietà del flusso. Che tengono conto
della dinamiche della zona di battigia.Il modello idrodinamico ROMS e il modello d’onda SWAN sono stati
entrambi utilizzati individualmente (soluzione di riferimento ROM Ss l) o in
combinazione con un di routine per il calcolo delle SBCs per il calcolo di
una linea di riva media e per fornire lungo di essa le condizione al contorno
(SBCS) che tengono conto della dinamica della zona di battigia (soluzione
ROM SSBC da testare). La forzante è stata fornita imponendo treni dionde
entranti lungo il bordo del dominio di calcolo a largo di SWAN.
L’utilizzo di ROM Ssl ad alte risoluzioni, consente di raggiungere ac-
que poco profonde dove la condizione di muro artificiale descrive bene il
movimento litorale.
Utilizzando le SBCs proposte ci hanno permesso di riprodurre una linea
di riva simile a quella ottenuta da ROM Ssl con una risoluzione di 0,1 m ma
utilizzando una griglia più grossolana di 4 m. Alla risoluzione più grossolana
di 8 m anche le SBCs proposte non possono adeguatamente rappresentare xl .
Il tempo necessario per la simulazione eseguita con ROMS ad alta ri-
soluzione è dell’ordine di alcune ore, mentre quello effettuato con le SBCs
proposte con una risoluzione quaranta volte più grossolana è dell’ordine di
alcuni minuti. Qui, il grande vantaggio, in termini di costo computazionale,
di utilizzare le proposte SBC è molto evidente.
Analisi parametriche dell’equazione di evoluzione della linea di riva media,
rivela che il volume della zona di battigia, sembra cambiare per importanza
tra i diversi esperimenti numericiAnalysis and Development of Oceanographic Models: reaching the Swash Zone The swash zone is the part of the beach where the final dissipation of short- wave energy usually occurs, while low-frequency wave energy is, generally, reflected back to sea. In addition, there is generation and reflection of further low-frequency waves. Swash zone flows are of fundamental importance not only because of their local effects but also because they can affect the surf zone dynamics as a whole. Notwithstanding its importance, typical circulation models do not account for the swash zone dynamics and simplified boundary conditions are often used, like that of perfect absorption or perfect reflection (rigid wall), at the inshore boundary of the computational domain. However, within such infinitesimal swash zone no generation or modification of low frequency waves can occur and all incoming low frequency waves are reflected at a single point. With this contribution we explore the possibility of implementing into wave-averaged solvers, a theoretical model that gives full account, through an integral approach, of the swash zone dynamics. Once such model is im- plemented, the wave-averaged solver will be able to calculate the position of a mean shore line and provide along it shoreline boundary condition (SBCs) which take in account of the swash zone dynamics.The hydrodynamic model ROMS and the wave driver SWAN have been both run alone into the COAWST modeling system (reference solution ROM Ssl ) and run in conjunction with a purpose-built routine for both: the calcula- tion of a mean shoreline and to provide along it shoreline boundary condi- tion (SBCs) which take into account of the swash zone dynamics (solution ROM SSBCs to be tested). Forcing was provided by imposing shore-normal waves at the off-shore boundary of the SWAN domain. Running ROM Ssl at really high resolutions, allows to reach the very shallow waters where the artificial shoreline conditions of rigid wall describes well the shoreline motion. Using the proposed SBCs allowed us to reproduce a shoreline close to the one obtained by ROM Ssl with a 0.1 m cross-shore resolution, but using a much coarser grid of 4 m. At the coarser resolution of 8 m also the proposed SBCs cannot properly represent xl . The time needed for the simulation run with the best resolved ROMS solution is in the order of some hours, while the one carried out with the proposed SBCs and a fourty times coarser cross-shore resolution is in the order of some minutes. Hence, the great advantage, in terms of computational costs, of using the proposed SBCs is very evident. A parametric analysis of the evolution equation for the mean shoreline reveals that the swash zone volume, seems to change in importance across different numerical experiments thus, further investigations are needed to clarify its importance. Sensitivity analyses have been carried out also to test the best location where to start the integration of the Riemann function. These analysis confirmed the importance of a good estimation of positive Riemann variable for a good estimation of the shoreline motion.
31
Al, Kaabi Ahmed Musabbeh. "Multi-dimensional sustainability framework for service organisations in the GCC countries." Thesis, Brunel University, 2014. http://bura.brunel.ac.uk/handle/2438/10589.
Full textAbstract:
Sustainability in the business context seeks to create long-term value by seizing the opportunities and overcoming the challenges of simultaneously addressing the organization’s economic, environmental and social responsibilities. Several sustainability models and frameworks have been put forward over the past three decades, aiming at helping organizations embed sustainability at the core of their businesses. Their relevancy and applicability are significant, particularly for the manufacturing sector and the overall value chain, even though service organizations are equally important stakeholders in this process. The raising interest to promote sustainability-focused practices, processes and policies in organizations in the Gulf Co-operation Council (GCC) region, particularly across the service sector, have contributed to define the goal of this research, namely: to establish the main drivers and challenges faced by local service organizations to embed sustainability at the core of their business strategy and practice, in order to develop an innovative multi-dimensional sustainability framework specifically adapted to the service sector in the GCC countries’ socio-cultural and economic environment. For this purpose, a research path was followed which included: comparative critical analysis of the leading organizational sustainability frameworks and maturity models; an empirical evaluation of their relevancy in the particular context of GCC countries; and primary research to confirm the perceived applied research gap and to evaluate the feasibility and relevancy of putting forward a sector specific framework. The outcome of this research is an innovative multi-dimensional sustainability framework for service sector organizations in the GCC region, which will provide stronger guidance on how to select and implement the most relevant sustainability aspects within the local service sector businesses, thus allowing them to develop better sustainability-focused policies and practices in the workplace. This framework will also contribute to academic community by opening new views on how sustainability is perceived and what adjustments are needed for it to work in the service sector in the context of GCC countries. This framework can later on be extended to other countries of the MENA region, where existing sustainability models and frameworks would not be fit for purpose. The framework hereby proposed was validated by combining the quantitative research and qualitative data collection and analysis using a combined positivist and interpretive case study strategy based on carefully selected cases across the service sector in the GCC countries. The measurable success of this framework will be the time it will take to reach a significant number of service sector organizations in the GCC countries that achieve the ideal balance between their social, economic and environmental dimensions with few constraints, thus becoming potential leaders of change for a more sustainable and inclusive successful future.
32
Toufigh, Vahab. "Experimental and Analytical Studies of Geo-Composite Applications in Soil Reinforcement." Diss., The University of Arizona, 2012. http://hdl.handle.net/10150/255167.
Full textAbstract:
The main weakness of soil is its inability to resist tensile stresses. Civil engineers have been trying to address this problem for decades. To increase the tensile and shear strengths of soil, different methods of reinforcing such as using geosynthetics have been used in different types of earth structures such as retaining walls, earth dams, slopes, etc. Due to the excellent corrosion resistance of polymers, the use of geosynthetics has increased dramatically in recent years. However, there are some significant problems associated with geosynthetics, such as creep and low modulus of elasticity. In this research, a new Geo-Composite which is made of Carbon Fiber Reinforced Polymer (CFRP) is used to overcome some of the short comings of the existing geosynthetics. The new Geo-Composite has all the benefits of the geotextiles plus higher strength, higher modulus and no creep. In first part of the investigation, over eighty experiments were carried out using direct shear test. The interface properties of the Geo-Composite (CFRP) and fine sand were investigated. Tests showed that the interface shear behavior between Geo-Composite and fine sand depended on the normal forces during the curing of epoxy and curing age of epoxy. The two methods used to prepare the specimen are pre-casting and casting in place, and the results of these two methods are compared. In the second part of the investigation, the pull-out test device was designed and assembled using a triaxial loading device and a direct shear device. In the pull-out test, the normal force applied by the triaxial loading and pull out force is applied by a direct shear device. CFRP samples were prepared in the lab, and pre-cast and cast-in-place samples were tested using fine sand. The pull-out force and corresponding displacements of each of the materials were recorded and compared. In the third part of the investigation, the behavior of the interface between coarse sand and modified CFRP has been studied in larger scale using a device known as Cyclic Multi Degree of Freedom (CYMDOF) device. A constitutive Model, Hierachical Single Surface (HISS) model, is used to characterize the behavior of the interfaces. The constitutive model is verified by predicting the laboratory behavior of interface. In the forth part of the investigation, using the laboratory test data results, a finite element procedure with the hardening model is used to simulate field behavior of a CFRP reinforced earth retaining wall, and compare the results with a geotextile reinforced earth retaining wall. This section shows the advantages and disadvantages of using CFRP in MSE walls.
33
Zörner, Dorit. "Prognose des Schwermetallhaushaltes von Landschaften mit dem Modell ATOMIS." Giessen Giessener Elektronische Bibliothek, 2010. http://geb.uni-giessen.de/geb/volltexte/2010/7488/index.html.
Full text
34
Dunn-Sigouin, Etienne. "Evaluation of northern hemisphere blocking climatology in the global environment multiscale (GEM) model and in the present and future climate as simulated by the CMIP5 models." Thesis, McGill University, 2012. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=110589.
Full textAbstract:
The performance of the Global Environmental Multiscale (GEM) model, Canadian operational numerical model, in reproducing atmospheric low-frequency variability is first evaluated in the context of Northern Hemisphere blocking climatology. The validation is conducted by applying a comprehensive but relatively simple blocking detection algorithm. Comparison to reanalysis reveals that the maximum blocking frequency over the north Atlantic and western Europe is generally underestimated and its peak season is delayed from late winter to spring. This contrasts with the blocking frequency over the north Pacific which is generally overestimated during all seasons. The biases in blocking frequency are found to be largely associated with the biases in climatological background flow. Specifically, modelled stationary wave shows a seasonal delay in zonal wavenumber 1 and an eastward shift in zonal wavenumber 2 components. Next, we extend our methodology to preliminary analyses of Northern Hemisphere blocking climatology from a subset of climate models participating in the Coupled Model Inter-comparison Project phase 5 (CMIP5). Historical integrations reveal that the maximum Euro-Atlantic blocking frequency is generally underestimated during the cold season and that significant overestimation of maximum Pacific blocking frequency occurs throughout the year in some models, as compared to reanalysis. In contrast, RCP8.5 integrations show a weak hint of reduced blocking frequency over the Pacific sector in comparison to historical integrations. However, no significant trend in terms of block duration within the RCP8.5 integrations is found.Les performances du modele Global Environment Multiscale (GEM), qui est le modele numerique operationel Canadien, a reproduire les variabilites atmospheriques de basse frequence sont evaluees en premier lieu dans le contexte de la climatologie de bloquage atmospherique dans l'hemisphere Nord. Afin de valider le modele, un algorithme de detection de bloquage qui est a la fois comprehensif et relativement simple est applique aux donnees atmospheriques. Les resultats montrent que la frequence maximum de bloquage au dessus de l'Atlantique Nord et l'Europe de l'Ouest est generalement sous-estimee et il y un delai dans la saison d'amplitude maximale puisqu'elle se produit au printemps au lieu de tard en hiver. De plus, la frequence de bloquage est generalement sur-estimee au dessus du Pacifique Nord. Il a ete trouve que les erreurs dans la frequence de bloquage sont grandement associees aux erreurs dans la circulation climatologique de l'atmosphere. En fait, les ondes stationnaires modelisees montrent un delai saisonnier dans le nombre d'onde zonal 1 et un deplacement vers l'Est des composantes du nombre d'onde zonal 2. Ayant confiance en la capacite de notre index pour identifier des bloquages atmospheriques, nous appliquons notre methodologie sur des analyses preliminaires de bloquage climatologique dans l'hemisphere Nord a partir d'un sous-ensemble de modeles climatologiques faisant partie du Coupled Model Inter-Comparison Project Phase 5 (CMIP5). Les integrations historiques revelent que la frequence maximale de bloquage sur l'Euro-Atlantique est generalement sous-estimee durant la saison froide et que la sur-estimation de la frequence maximale de bloguage sur le Pacifique se produit tout au long de l'annee dans certains modeles. En comparaison, les integrations de type RCP8.5 montrent un leger indice d'une reduction de la frequence de bloquage sur le Pacifique meme si aucune tendance significative en terme de duree de bloquage n'a ete trouvee.
35
Upton, Danielle. "The United Arab Emirates: An Economic Role Model for the GCC." Honors in the Major Thesis, University of Central Florida, 2007. http://digital.library.ucf.edu/cdm/ref/collection/ETH/id/1234.
Full textAbstract:
This item is only available in print in the UCF Libraries. If this is your Honors Thesis, you can help us make it available online for use by researchers around the world by following the instructions on the distribution consent form at http://library.ucf.edu/Systems/DigitalInitiatives/DigitalCollections/InternetDistributionConsentAgreementForm.pdf You may also contact the project coordinator, Kerri Bottorff, at kerri.bottorff@ucf.edu for more information.Bachelors
Sciences
Political Science
36
Ceniceros, Angelica, and Angelica Ceniceros. "Comparison of Model Predicted and Observed Light Curves of GEO Satellites." Thesis, The University of Arizona, 2017. http://hdl.handle.net/10150/625339.
Full textAbstract:
Although the amount of light received by sensors on the ground from Resident Space Objects (RSOs) in geostationary orbit (GEO) is small, information can still be extracted in the form of light curves (temporal brightness or apparent magnitude). Previous research has shown promising results in determining RSO characteristics such as shape, size, reflectivity, and attitude by processing simulated light curve data with various estimation algorithms. These simulated light curves have been produced using one of several existing analytic Bidirectional Reflectance Distribution Function (BRDF) models. These BRDF models have generally come from researchers in computer graphics and machine vision and have not been shown to be realistic for telescope observations of RSOs in GEO. While BRDFs have been used for Space Situational Awareness (SSA) analysis and characterization, there is a lack of research on the validation of BRDFs with real data. This research is focused on comparing telescope data provided by Applied Defense Solutions, as processed by their Efficient Photometry In-Frame Calibration (EPIC) software, with predicted light curves based on the Ashikhmin-Premoze BRDF and two additional popular illumination models, Ashikhmin-Shirley and Cook-Torrance. I computed predicted light curves based on two line mean elements (TLEs), shape model, attitude profile, observing ground station location, observation time and BRDF. The selected BRDFS provided accurate apparent magnitude trends and behavior, but uncertainties due to lack of attitude information and deficiencies in our satellite model prevented us from obtaining a better match to the real data.
37
Ferrarin, Christian <1975>. "A sediment transport model for the lagoon of Venice." Doctoral thesis, Università Ca' Foscari Venezia, 2007. http://hdl.handle.net/10579/636.
Full text
38
Oliveira, Lorena Tavares de. "Avalia??o gen?tica da probabilidade de prenhez em novilhas da ra?a Sindi via modelos de limiar em regress?o aleat?ria." UFVJM, 2016. http://acervo.ufvjm.edu.br/jspui/handle/1/1289.
Full textAbstract:
Submitted by Jos? Henrique Henrique (jose.neves@ufvjm.edu.br) on 2017-03-07T17:37:49Z
No. of bitstreams: 2
license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5)
lorena_tavares_oliveira.pdf: 1039032 bytes, checksum: 99b6c1aac4a55a13ac7523067c7e14af (MD5)Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2017-03-30T14:58:02Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) lorena_tavares_oliveira.pdf: 1039032 bytes, checksum: 99b6c1aac4a55a13ac7523067c7e14af (MD5)
Made available in DSpace on 2017-03-30T14:58:02Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) lorena_tavares_oliveira.pdf: 1039032 bytes, checksum: 99b6c1aac4a55a13ac7523067c7e14af (MD5) Previous issue date: 2016
Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES)
Funda??o de Amparo ? Pesquisa do Estado de Minas Gerais (FAPEMIG)
Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq)
Objetivou-se com este estudo estimar par?metros gen?ticos e fenot?picos para probabilidade de prenhez nas idades 15, 19, 23, 27, 31, 35, 39 e 43 meses (PP_15, PP_19, PP_23, PP_27, PP_31, PP_35, PP_39 e PP_43), em novilhas da ra?a Sindi, via modelo de limiar em regress?o aleat?ria utilizando os polin?mios ortogonais de Legendre de segunda, terceira e quarta ordem, considerando a homogeneidade e heterogeneidade de vari?ncia residual. Os componentes de covari?ncia foram estimados por abordagem Bayesiana, utilizando o programa THRGIBBS3F90. Foram inclu?dos os efeitos fixos de criador, fazenda do criador, ano de nascimento, esta??o de nascimento e como covari?vel (de efeito linear) foi considerado o peso da vaca na idade em que ela concebeu. Al?m desses efeitos para todas as idades estudadas, foram considerados os efeitos aleat?rios gen?ticos aditivos, de ambiente permanente e residual. O melhor modelo para a an?lise RRTM foi o LEG_4441 que obteve as seguintes estimativas de herdabilidade 0,34; 0,41; 0,45; 0,41; 0,37; 0,32; 0,32; 0,33 para PP_15, PP_19, PP_23, PP_27, PP_31, PP_35, PP_39, PP_43, respectivamente. As estimativas das correla??es gen?ticas obtidas entre PP_15 com PP_19, PP_23, PP_27, PP_31, PP_35, PP_39 e PP_43 foram 0,1; -0,39; -0,65; -0,83; -0,93; -0,81; -0,71, respectivamente. As estimativas das correla??es fenot?picas para PP_15 com PP_19, PP_23, PP_27, PP_31, PP_35, PP_39 e PP_43 foram respectivamente 0,12; -0,09; -0,17; -0,22; -0,26; -0,25; 0,40. A an?lise que utilizou modelo LEG_4441 foi a mais indicada para estimar os par?metros gen?ticos para a probabilidade de prenhez em diferentes idades em novilhas da ra?a Sindi, indicando que a prenhez precoce possui variabilidade gen?tica para ser inclu?da como caracter?stica alvo de sele??o em programas de melhoramento, com potencial para se obter ganhos gen?ticos satisfat?rios.
Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Zootecnia, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2016.
Our aim with this study was estimating genetic and phenotypic parameters for pregnancy probability at 15, 19, 23, 27, 31, 35, 39 and 43 month old (PP_15, PP_19, PP_23, PP_27, PP_31, PP_35, PP_39 and PP_43) in Sindhi heifers, by using threshold model in a random regression framework, adopting Legendre orthogonal polynomials of second, third and fourth order, considering homogeneity and heterogeneity of residual variance. Covariance components were estimated by Bayesian approach using THRGIBBS3F90 program. The model included the fixed effects of herd, herd of the farm, year of birth, birth season and as a covariate (with linear effect) was considered the weight of the cow at the age when she calved. In addition to these effects for all ages studied, additive genetic, permanent environmental and residual random effects were considered. The best model for the analysis was the RRTM LEG_4441 which obtained the following heritability estimates: 0.34; 0.41; 0.45; 0.41; 0.37; 0.32; 0.32; 0.33 to PP_15, PP_19, PP_23, PP_27, PP_31, PP_35, PP_39 and PP_43, respectively. Genetic correlation estimates between PP_15 with PP_19, PP_23, PP_27, PP_31, PP_35, PP_39 and PP_43 were 0.1; -0.39; -0.65; -0.83; -0.93; -0.81; -0.71, respectively. Phenotypic correlation estimates for PP_15 with PP_19, PP_23, PP_27, PP_31, PP_35, PP_39 and PP_43 were respectively 0.12; -0.09; -0.17; -0.22; -0.26; -0.25; 0.40. The analysis by using LEG_4441 model was the most appropriate to estimate genetic parameters for pregnancy probability at different ages in Sindhi heifers, indicating that early pregnancy has genetic variability to be included as a goal trait selection in breeding programs, with the potential to achieve satisfactory genetic gains.
39
RICOL, STEPHANIE. "Etude du gel d'alteration des verres nucleaires et synthese de gels modeles." Paris 6, 1995. http://www.theses.fr/1995PA066714.
Full textAbstract:
Ce travail s'inscrit dans le cadre general des etudes sur l'alterabilite du verre nucleaire de reference r7t7. Il s'interesse plus particulierement a la pellicule formee a la surface de ce verre lors de son alteration. Contrairement aux etudes ulterieures qui portent principalement sur les cinetiques de dissolution des verres a partir des analyses chimiques des elements lixivies, il aborde le probleme de l'alteration a partir de l'etude structurale du verre de depart et du gel de surface. Cette demarche permet d'identifier les mecanismes de formation du gel et d'expliquer en partie le comportement a la lixiviation des elements. Ces deux approches se sont en fait averees complementaires et indissociables. A partir de differentes techniques spectroscopiques, ce travail a mis en evidence le role particulier de certains cations du verre tels que le calcium, le zirconium et le fer. Les etudes realises sur des gels de synthese a base de silice ont montre l'effet synergique d'un cation modificateur de reseau et d'un cation formateur de coordinence elevee sur une matrice de silice. La reticulation du reseau peut etre reliee au nombre d'onde de la bande de vibration asymetrique de la liaison si-o, pour les systemes ternaires si/na/zr. Par contre, les pertes de masse en silicium de ces materiaux dependent du nombre d'oxygenes non pontants. D'un point de vue du comportement a long terme, le gel d'alteration presente des caracteristiques proches mais superieures a celles du verre de depart. C'est donc un materiau tres stable en conditions statiques. De meme, les gels de synthese sont des materiaux presentant des solubilites tres faibles et nettement inferieures au gel d'alteration, ce qui pourrait leur conferer un role de matrice de confinement
40
Freitas, Leandro Alexandre. "Programação de espaços inteligentes utilizando modelos em tempo de execução." Universidade Federal de Goiás, 2017. http://repositorio.bc.ufg.br/tede/handle/tede/7353.
Full textAbstract:
Submitted by JÚLIO HEBER SILVA (julioheber@yahoo.com.br) on 2017-05-19T17:39:41Z
No. of bitstreams: 2
Tese - Leandro Alexandre Freitas - 2017.pdf: 10640805 bytes, checksum: 61b69f91cb32e17075d698eecf19b8c4 (MD5)
license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5)Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2017-05-22T10:42:45Z (GMT) No. of bitstreams: 2 Tese - Leandro Alexandre Freitas - 2017.pdf: 10640805 bytes, checksum: 61b69f91cb32e17075d698eecf19b8c4 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5)
Made available in DSpace on 2017-05-22T10:42:45Z (GMT). No. of bitstreams: 2 Tese - Leandro Alexandre Freitas - 2017.pdf: 10640805 bytes, checksum: 61b69f91cb32e17075d698eecf19b8c4 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-04-04
Fundação de Amparo à Pesquisa do Estado de Goiás - FAPEG
The growth and popularization of wireless connectivity and of mobile devices has allowed the development of smart spaces that were previously only envisaged in the approach proposed by Mark Weiser. These smart spaces are composed of many computational resources, such as devices, services and applications, along with users, who must be able to associate with these features. However, programming these environments is a challenging task, since smart spaces have a dynamic nature, resources are heterogeneous, and it is necessary that interactions between users and devices are coordinated with one another. In this work, we present a new approach for smart spaces programming using Models@RunTime. In this regard, we propose a high level modeling language, called Smart Spaces Modeling Language (2SML), in which the user is able to model the smart space with all elements that can be part of it. Such models are developed by the users, interpreted and effected in the physical space by a model execution engine, called Smart Space Virtual Machine (2SVM), whose development is part of this work.
O crescimento e a popularização cada vez maior da conectividade sem fio e dos dispositivos móveis, tem permitido a construção de espaços inteligentes que antes eram vislumbrados apenas na proposta de computação ubíqua do cientista da Xerox PARK, Mark Weiser. Esses espaços inteligentes são compostos por diversos recursos computacionais, como dispositivos, serviços e aplicações, além de usuários, que devem ser capazes de se associar a esses recursos. Entretanto, a programação destes ambientes é uma tarefa desa- fiadora, uma vez que os espaços inteligentes possuem uma natureza dinâmica, os recursos se apresentam de forma heterogênea e é necessário que as interações entre usuários e dispositivos sejam coordenadas. Neste trabalho desenvolvemos uma nova abordagem para programação de espaços inteligentes, por meio de modelos em tempo de execução. Para isso, propomos uma linguagem de modelagem de alto nível, denominada Smart Space Modeling Language (2SML), em que o usuário é capaz de modelar o espaço inteligente com todos os elementos que dele podem fazer parte. Esse modelo desenvolvido pelo usuá- rio é interpretado e realizado no espaço físico por uma máquina de execução de modelos, denominada Smart Space Virtual Machine (2SVM), cujo desenvolvimento é parte deste trabalho.
41
Maccaferri, Francesco <1980>. "Numericals and analogue models of fluid-filled fractures propagation in layered media: application to dikes and hydrofractures." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2010. http://amsdottorato.unibo.it/2938/1/maccaferri_francesco_tesi.pdf.
Full text
42
Maccaferri, Francesco <1980>. "Numericals and analogue models of fluid-filled fractures propagation in layered media: application to dikes and hydrofractures." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2010. http://amsdottorato.unibo.it/2938/.
Full text
43
Kyriakopoulos, Christodoulos <1978>. "Finite element models of coseismic deformation due to the 2009 L'Aquila (Italy) and 2008 Wenchuan(China) earthquakes." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2011. http://amsdottorato.unibo.it/3685/1/Kyriakopoulos_Christodoulos_tesi.pdf.
Full textAbstract:
The topic of my Ph.D. thesis is the finite element modeling of coseismic deformation imaged by DInSAR and GPS data. I developed a method to calculate synthetic Green functions with finite element models (FEMs) and then use linear inversion methods to determine the slip distribution on the fault plane. The method is applied to the 2009 L’Aquila Earthquake (Italy) and to the 2008 Wenchuan earthquake (China). I focus on the influence of rheological features of the earth's crust by implementing seismic tomographic data and the influence of topography by implementing Digital Elevation Models (DEM) layers on the FEMs. Results for the L’Aquila earthquake highlight the non-negligible influence of the medium structure: homogeneous and heterogeneous models show discrepancies up to 20% in the fault slip distribution values. Furthermore, in the heterogeneous models a new area of slip appears above the hypocenter. Regarding the 2008 Wenchuan earthquake, the very steep topographic relief of Longmen Shan Range is implemented in my FE model. A large number of DEM layers corresponding to East China is used to achieve the complete coverage of the FE model. My objective was to explore the influence of the topography on the retrieved coseismic slip distribution. The inversion results reveals significant differences between the flat and topographic model. Thus, the flat models frequently adopted are inappropriate to represent the earth surface topographic features and especially in the case of the 2008 Wenchuan earthquake.
44
Kyriakopoulos, Christodoulos <1978>. "Finite element models of coseismic deformation due to the 2009 L'Aquila (Italy) and 2008 Wenchuan(China) earthquakes." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2011. http://amsdottorato.unibo.it/3685/.
Full textAbstract:
The topic of my Ph.D. thesis is the finite element modeling of coseismic deformation imaged by DInSAR and GPS data. I developed a method to calculate synthetic Green functions with finite element models (FEMs) and then use linear inversion methods to determine the slip distribution on the fault plane. The method is applied to the 2009 L’Aquila Earthquake (Italy) and to the 2008 Wenchuan earthquake (China). I focus on the influence of rheological features of the earth's crust by implementing seismic tomographic data and the influence of topography by implementing Digital Elevation Models (DEM) layers on the FEMs. Results for the L’Aquila earthquake highlight the non-negligible influence of the medium structure: homogeneous and heterogeneous models show discrepancies up to 20% in the fault slip distribution values. Furthermore, in the heterogeneous models a new area of slip appears above the hypocenter. Regarding the 2008 Wenchuan earthquake, the very steep topographic relief of Longmen Shan Range is implemented in my FE model. A large number of DEM layers corresponding to East China is used to achieve the complete coverage of the FE model. My objective was to explore the influence of the topography on the retrieved coseismic slip distribution. The inversion results reveals significant differences between the flat and topographic model. Thus, the flat models frequently adopted are inappropriate to represent the earth surface topographic features and especially in the case of the 2008 Wenchuan earthquake.
45
OCCHIPINTI, SUSANNA. "Models and guidelines for more effective tools and paths in an active teaching-learning in Earth sciences: looking for an unifying principle." Doctoral thesis, Università degli Studi di Camerino, 2014. http://hdl.handle.net/11581/401821.
Full text
46
Sukarevičienė, Gintarė. "Developing business model for geo-location database for the operation of cognitive radio in the TV white space bands." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2012. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2012~D_20120620_111925-58983.
Full textAbstract:
The aim of this thesis is to analyze how technological, economic, political and social factors can be integrated into Business Model for Geo-location database as a controlling entity for operation of Cognitive Radio devices in the TV White Space spectrum range.
Tasks of thesis: to perform an analysis of scientific literature in the context of TVWS and to identify technologies of TVWS management, to find factors influencing Geo-location Database Business Model, to put forward Geo-location Database scenarios, to construct classification of Business Model for the Geo-location Database, to provide experimental study of feasibility to deploy distinct classification of Business Model for the distinct scenarios of Geo-location Database.
Qualitative methods chosen for the research: exploratory literature analysis, consultations with experts/specialists and conceptual modelling based on scenarios.
The exploratory part of the thesis describes existing spectrum shortage problem and presents potential technologies that can solve this problem.
The theoretical part of this work introduces research methodology and the concept and principles of Business Model for technology innovation.
Analytical part of the thesis seeks to identify potential Business Model configurations for the operations of Geo-location database in the TV White Space spectrum range. This part ends with presenting experimental study of the feasibility of Geo-location Business Model.
The final part of the thesis concludes... [to full text]Šio darbo tikslas – išanalizuoti, kaip technologiniai, ekonominiai, politiniai ir socialiniai faktoriai gali būti integruoti į verslo modelį, skirtą TV spektro tuštumų geografinei duomenų bazei, naudojančiai sumaniojo radijo ryšio sistemas. Tikslui pasiekti išsikelti uždaviniai: atlikti mokslinės literatūros analizę TV spektro tuštumų tema ir identifikuoti spektro tuštumų valdymo technologijas, nustatyti veiksnius, įtakojančius geografinės duomenų bazės verslo modelį, sudaryti geografinės duomenų bazės verslo scenarijus, sudaryti geografinės duomenų bazės verslo modelių klasifikaciją, nustatyti sudarytos verslo modelių klasifikacijos tinkamumą kiekvienam scenarijui bei nustatyti optimalią verslo modelio konfigūraciją. Uždaviniams įgyvendinti taikyti kokybiniai metodai: mokslinės literatūros analizė, konsultacijos su ekspertais bei specialistais, konceptualus modeliavimas, paremtas scenarijų metodu. Pirmoje darbo dalyje aprašomos egzistuojančios spektro trūkumo problemos ir apžvelgiamos potencialios technologijos, kurios gali išspręsti išanalizuotą problemą. Antroji darbo dalis pristato tyrimo metodus ir nagrinėja verslo modelį bei jo principus, galinčius įtakoti technologijos inovaciją. Trečioji darbo dalis siekia identifikuoti ir įvertinti potencialius TV spektro tuštumų geografinės duomenų bazės verslo modelius. Pateikiamos darbo išvados atsižvelgiant į darbo naudingumą, praktiškumą ir esamus apribojimus. Pagrindiniai darbo rezultatai: nustatyta optimali verslo modelių... [toliau žr. visą tekstą]
47
Pinto, Victor Hugo e. Araujo. "Mn(III)-porfirinas como catalisadores biomiméticos: estabilidade térmica e imobilização em vermiculita e sílica gel funcionalizada para hidroxilação de alcanos." Universidade Federal da Paraíba, 2013. http://tede.biblioteca.ufpb.br:8080/handle/tede/7133.
Full textAbstract:
Made available in DSpace on 2015-05-14T13:21:34Z (GMT). No. of bitstreams: 1
arquivototal.pdf: 8221472 bytes, checksum: cac315a193674c3a77482441306e409a (MD5)
Previous issue date: 2013-11-03Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
An alternative route for the synthesis of the three isomers of Mn(III) N-metylpyridylporphyrins, MnTM-X-PyPCl5 (X = 2, 3, 4) was developed by the direct methylation of MnT-X-PyPCl (X = 2, 3, 4) with methyl tosylate; this methodology may be adapted for preparing the longer-alkyl-chain analogues. The investigation of the thermal stability of the potent redox modulator Mn(III) meso-tetrakis(N-ethylpyridinium-2- yl)porphyrin chloride (MnTE-2-PyPCl5) showed that the thermal decomposition of MnTE-2-PyPCl5∙11H2O under air occurs in three successive steps: dehydration, dealkylation (ethyl chloride loss) and combustion, to yield Mn oxide as final residue. Heating MnTE-2-PyPCl5∙11H2O up to ~100 ºC leads to dehydration, but with no effect onto the catalytic SOD activity after rehydration/dissolution. Heating the sample at temperatures above 100 ºC leads to dealkylation, which affects catalytic and biological properties. The immobilization of the neutral Mn porphyrins (MnPs) MnT-X-PyPCl (X = 2, 3, 4) covalently onto chloropropyl silica-gel (Sil-Cl) or the cationic MnPs MnTM-X-PyPCl5 (X = 2, 3, 4) electrostatically into sodium vermiculite (verm) yielded stable biomimetic models of cytochromes P450. The resulting materials, Sil-Cl/MnT-X-PyPCl e verm/MnTM-X-PyPCl5 (X = 2, 3, 4), were used as oxidation catalyst for hydroxylation of cyclohexane and adamantane by iodosylbenzene. The heterogeneous systems were more efficient, selective, and oxidatively stable than the homogeneous counterparts, and could be reused three times with no significant loss in efficiency. The use of more drastic conditions (i.e., large excess of PhIO), led to considerable decrease in efficiency, which was partial recovered upon catalyst reuse uner milder conditions, indicating that the support protects the supported MnP against oxidative degradation. The materials efficiently catalyzed the oxidation of cyclohexanol to cyclohexanone, suggesting that the ketone observed during cyclohexane hydroxylation may result, at least partially, from cyclohexanol oxidation. The covalent bond between Sil-Cl and MnPs via N-pyridyl moiety allowed the preparation of efficient and stable catalysts, even with first generation, simple MnPs, such as MnT-X-PyPCl (X = 2, 3, 4). Vermiculite was revealed as a simple and effective support for rapid and qualitative immobilization of cationic MnPs, MnTM-X-PyPCl5 (X = 2, 3, 4). Grinding of the vermiculite-based materials decreased the crystallinity of the systems, which was followed by an increase in the catalytic efficiency of the meta and para isomers verm/MnTM-X-PyPCl5 (X = 3 and 4), but did not affect of the high efficiency of the immobilized ortho isomer (verm/MnTM-2-PyPCl5), whose resistance to oxidative destruction and/or leaching was, additionally, higher than that of the other isomers.
Neste trabalho foi desenvolvida uma rota alternativa para obtenção dos três isômeros das N-metilpiridinioporfirinas de Mn(III), MnTM-X-PyPCl5 (X = 2, 3, 4), a partir da metilação direta dos complexos MnT-X-PyPCl (X = 2, 3, 4) com tosilato de metila; esta metodologia pode ser adaptada para obtenção de derivados alquilas de cadeias maiores. A investigação da estabilidade térmica do modulador redox potente cloreto de meso-tetraquis(N-etilpiridinio-2-il)porfirinatomanganês(III) (MnTE-2-PyPCl5) revelou que a decomposição térmica da MnTE-2-PyPCl5∙11H2O em ar ocorre em três etapas sucessivas, associadas à desidratação, desalquilação (perda dos grupos EtCl) e combustão, levando a óxidos de Mn como resíduo final. O aquecimento da MnTE-2- PyPCl5∙11H2O até ~100 °C leva à desidratação, mas não afeta a atividade catalítica SOD após a re-hidratação/dissolução. O aquecimento da amostra à temperatura elevada (>100 oC) leva à desalquilação e compromete as propriedades catalíticas e biológicas da amostra. O desenvolvimento de modelos biomiméticos dos citocromos P450 pela heterogeneização covalente das Mn-porfirinas (MnPs) neutras MnT-X-PyPCl (X = 2, 3, 4) na sílica cloropropil (Sil-Cl) e pela heterogeneização eletrostática das MnPs catiônicas MnTM-X-PyPCl5 (X = 2, 3, 4) na vermiculita de sódio (verm) foi estudado. Os materiais resultantes, Sil-Cl/MnT-X-PyPCl e verm/MnTM-X-PyPCl5 (X = 2, 3, 4), foram empregados como catalisadores em reações de hidroxilação de cicloexano e adamantano por iodosilbenzeno (PhIO). Os catalisadores heterogeneizados foram mais eficientes, seletivos e resistentes à destruição oxidativa do que os catalisadores em meio homogêneo, e foram reutilizados por três vezes sem perda significativa na eficiência catalítica. Sob condições mais drásticas, com o uso de grande excesso de PhIO, há diminuição considerável da eficiência, mas os catalisadores imobilizados puderam ser reutilizados com recuperação parcial da eficiência, o que indica que o suporte exerce proteção das MnPs contra degradação oxidativa. Os catalisadores heterogeneizados foram eficientes ao catalisar a oxidação do cicloexanol à cicloexanona, sugerindo que a cetona observada nas hidroxilações pode advir da oxidação seqüencial, cicloexano-cicloexanol-cicloexanona. A ligação covalente entre a Sil-Cl e as MnPs via grupo N-piridil possibilitou a obtenção de catalisadores eficientes e estáveis, mesmo utilizando MnPs simples de primeira geração, MnT-X-PyPCl (X = 2, 3, 4). Já a vermiculita mostrou-se um suporte simples e efetivo para imobilização rápida e quantitativa de MnPs catiônicas, MnTM-X-PyPCl5 (X = 2, 3, 4). A pulverização dos materiais à base de vermiculita diminuiu a cristalinidade dos sistemas, promoveu um aumento na eficiência dos isômeros meta e para (verm/MnTM-X-PyPCl5, X = 3 e 4), mas não modificou a alta eficiência do isômero orto imobilizado (verm/MnTM-2-PyPCl5), cuja resistência à destruição oxidativa e/ou lixiviação foi superior à dos outros isômeros.
48
Park, Jeanseong. "Longitudinal Data Analysis Using Generalized Linear Model with Missing Responses." Thesis, Université d'Ottawa / University of Ottawa, 2015. http://hdl.handle.net/10393/33355.
Full textAbstract:
Longitudinal studies rely on data collected at several occasions from a set of selected individuals. The purpose of these studies is to use a regression-type model to express a response variable as a function of explanatory variables, or covariates. In this thesis, we use marginal models for the analysis of such data, which, coupled with the method of estimating equations, provide estimators of the main regression parameter. When some of the responses are missing or there is error in the recorded covariates, the original estimating equation may be biased. We use techniques available in the literature to modify it and regain the unbiasedness property. We prove the asymptotic normality of the regression estimator obtained under these more realistic circumstances, and provide theoretical and numerical examples to illustrate this approach.
49
Patara, Lavinia <1979>. "Bio-physical interactions and feedbacks in a global climate model." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2010. http://amsdottorato.unibo.it/2834/1/patara_lavinia_tesi.pdf.
Full textAbstract:
This PhD thesis addresses the topic of large-scale interactions between climate and marine biogeochemistry. To this end, centennial simulations are performed under present and projected future climate conditions with a coupled ocean-atmosphere model containing a complex marine biogeochemistry model. The role of marine biogeochemistry in the climate system is first investigated. Phytoplankton solar radiation absorption in the upper ocean enhances sea surface temperatures and upper ocean stratification. The associated increase in ocean latent heat losses raises atmospheric temperatures and water vapor. Atmospheric circulation is modified at tropical and extratropical latitudes with impacts on precipitation, incoming solar radiation, and ocean circulation which cause upper-ocean heat content to decrease at tropical latitudes and to increase at middle latitudes. Marine biogeochemistry is tightly related to physical climate variability, which may vary in response to internal natural dynamics or to external forcing such as anthropogenic carbon emissions. Wind changes associated with the North Atlantic Oscillation (NAO), the dominant mode of climate variability in the North Atlantic, affect ocean properties by means of momentum, heat, and freshwater fluxes. Changes in upper ocean temperature and mixing impact the spatial structure and seasonality of North Atlantic phytoplankton through light and nutrient limitations. These changes affect the capability of the North Atlantic Ocean of absorbing atmospheric CO2 and of fixing it inside sinking particulate organic matter. Low-frequency NAO phases determine a delayed response of ocean circulation, temperature and salinity, which in turn affects stratification and marine biogeochemistry. In 20th and 21st century simulations natural wind fluctuations in the North Pacific, related to the two dominant modes of atmospheric variability, affect the spatial structure and the magnitude of the phytoplankton spring bloom through changes in upper-ocean temperature and mixing. The impacts of human-induced emissions in the 21st century are generally larger than natural climate fluctuations, with the phytoplankton spring bloom starting one month earlier than in the 20th century and with ~50% lower magnitude. This PhD thesis advances the knowledge of bio-physical interactions within the global climate, highlighting the intrinsic coupling between physical climate and biosphere, and providing a framework on which future studies of Earth System change can be built on.
50
Patara, Lavinia <1979>. "Bio-physical interactions and feedbacks in a global climate model." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2010. http://amsdottorato.unibo.it/2834/.
Full textAbstract:
This PhD thesis addresses the topic of large-scale interactions between climate and marine biogeochemistry. To this end, centennial simulations are performed under present and projected future climate conditions with a coupled ocean-atmosphere model containing a complex marine biogeochemistry model. The role of marine biogeochemistry in the climate system is first investigated. Phytoplankton solar radiation absorption in the upper ocean enhances sea surface temperatures and upper ocean stratification. The associated increase in ocean latent heat losses raises atmospheric temperatures and water vapor. Atmospheric circulation is modified at tropical and extratropical latitudes with impacts on precipitation, incoming solar radiation, and ocean circulation which cause upper-ocean heat content to decrease at tropical latitudes and to increase at middle latitudes. Marine biogeochemistry is tightly related to physical climate variability, which may vary in response to internal natural dynamics or to external forcing such as anthropogenic carbon emissions. Wind changes associated with the North Atlantic Oscillation (NAO), the dominant mode of climate variability in the North Atlantic, affect ocean properties by means of momentum, heat, and freshwater fluxes. Changes in upper ocean temperature and mixing impact the spatial structure and seasonality of North Atlantic phytoplankton through light and nutrient limitations. These changes affect the capability of the North Atlantic Ocean of absorbing atmospheric CO2 and of fixing it inside sinking particulate organic matter. Low-frequency NAO phases determine a delayed response of ocean circulation, temperature and salinity, which in turn affects stratification and marine biogeochemistry. In 20th and 21st century simulations natural wind fluctuations in the North Pacific, related to the two dominant modes of atmospheric variability, affect the spatial structure and the magnitude of the phytoplankton spring bloom through changes in upper-ocean temperature and mixing. The impacts of human-induced emissions in the 21st century are generally larger than natural climate fluctuations, with the phytoplankton spring bloom starting one month earlier than in the 20th century and with ~50% lower magnitude. This PhD thesis advances the knowledge of bio-physical interactions within the global climate, highlighting the intrinsic coupling between physical climate and biosphere, and providing a framework on which future studies of Earth System change can be built on.