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Ozcaldiran, Kadri. "Control of descriptor systems." Diss., Georgia Institute of Technology, 1985. http://hdl.handle.net/1853/13531.
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Aubry, Mathieu. "Representing 3D models for alignment and recognition." Thesis, Paris, Ecole normale supérieure, 2015. http://www.theses.fr/2015ENSU0006/document.
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Cette thèse explore différentes représentations de modèles 3D pour la mise en correspondance de formes 3D, l’alignement d’une instance 2D et de son modèle 3D et l’alignement de modèles 3D à une image 2D pour toute une catégorie d’objets. La géométrie d’une forme 3D est presque entièrement encodée par les fonctions et valeurs propres de l’opérateur de Laplace-Beltrami sur cette forme. Nous utilisons cette représentation mathématiquement élégante pour caractériser les points d’une forme en développant une nouvelle notion d’échelle. Nous montrons que cette signature présente plusieurs avantages. Un élément clé de la compréhension d’une image est l’alignement des objets qu’elle contient à leur modèle 3D. Nous considérons ce problème d’alignement 2D-3D pour une représentation 2D arbitraire, telle un dessin ou une peinture. Nous représentons le modèle d’un site architectural par un ensemble d’elements visuels discriminants. Nous développons ensuite une procédure pour mettre ces éléments en correspondance avec une représentation 2D du site. Nous validons notre méthode sur une nouvelle base de données de représentations historiques et non-photographiques. Nous étendons cette approche pour décrire non pas un unique site architectural, mais une catégorie entière d’objets, représentée par une grande collection de modèles 3D. Notre méthode d’alignement 2D-3D pour une catégorie d’objets non seulement détecte les instances, mais identifie une approximation de leur style et de leur point de vue. Nous évaluons notre approche sur un sous-ensemble de la difficile base de donnée “Pascal VOC 2007” pour la catégorie des chaises, que nous représentons pas une base de donnée de 1394 modèles 3DThanks to the success of 3D reconstruction algorithms and the development of online tools for computer-aided design (CAD) the number of publicly available 3D models has grown significantly in recent years, and will continue to do so. This thesis investigates representations of 3D models for 3D shape matching, instance-level 2D-3D alignment, and category-level 2D-3D recognition. The geometry of a 3D shape can be represented almost completely by the eigen-functions and eigen-values of the Laplace-Beltrami operator on the shape. We use this mathematically elegant representation to characterize points on the shape, with a new notion of scale. This 3D point signature can be interpreted in the framework of quantum mechanics and we call it the Wave Kernel Signature (WKS). We show that it has advantages with respect to the previous state-of-the-art shape descriptors, and can be used for 3D shape matching, segmentation and recognition. A key element for understanding images is the ability to align an object depicted in an image to its given 3D model. We tackle this instance level 2D-3D alignment problem for arbitrary 2D depictions including drawings, paintings, and historical photographs. This is a tremendously diffcult task as the appearance and scene structure in the 2D depictions can be very different from the appearance and geometry of the 3D model, e.g., due to the specific rendering style, drawing error, age, lighting or change of seasons. We represent the 3D model of an entire architectural site by a set of visual parts learned from rendered views of the site. We then develop a procedure to match those scene parts that we call 3D discriminative visual elements to the 2D depiction of the architectural site. We validate our method on a newly collected dataset of non-photographic and historical depictions of three architectural sites. We extend this approach to describe not only a single architectural site but an entire object category, represented by a large collection of 3D CAD models. We develop a category-level 2D-3D alignment method that not only detects objects in cluttered images but also identifies their approximate style and viewpoint. We evaluate our approach both qualitatively and quantitatively on a subset of the challenging Pascal VOC 2012 images of the \chair" category using a reference library of 1394 CAD models downloaded from the Internet
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Aasaraai, A. "Geometric models in linear control theory : On disturbance decoupling in descriptor systems." Thesis, University of Salford, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.234563.
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Hobocienski, Bryan Christopher. "Locality-Dependent Training and Descriptor Sets for QSAR Modeling." The Ohio State University, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=osu1577716259011585.
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Wang, Siwen. "Orbital Level Understanding of Adsorbate-Surface Interactions in Metal Nanocatalysis." Diss., Virginia Tech, 2020. http://hdl.handle.net/10919/98923.
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We develop a theoretical framework for a priori estimation of catalytic activity of metal nanoparticles using geometry-based reactivity descriptors of surface atoms and kinetic analysis of reaction pathways at various types of active sites. We show that orbitalwise coordination numbers 𝐶𝑁α (α = 𝑠 or 𝑑) can be used to predict chemical reactivity of a metal site (e.g., adsorption energies of critical reaction intermediates) by being aware of the neighboring chemical environment, outperforming their regular (𝐶𝑁) and generalized (𝐶̅𝑁̅) counterparts with little added computational cost. Here we include two examples to illustrate this method: CO oxidation on Au (5𝑑¹⁰6𝑠¹) and O₂ reduction on Pt (5𝑑⁹6𝑠¹). We also employ Bayesian learning and the Newns-Anderson model to advance the fundamental understanding of adsorbate-surface interactions on metal nanocatalysts, paving the path toward adsorbate-specific tuning of catalysis.Doctor of Philosophy
The interactions between reaction intermediates and catalysts should be neither too strong nor too weak for catalytic optimization. This Sabatiers principle arising from the scaling relations among the energetics of reacting species at geometrically similar sites, provides the conceptual basis for designing improved catalysts, but imposes volcano-type limitations on the attainable catalytic activity and selectivity. One of the greatest challenges faced by the catalysis community today is how to develop design strategies and ultimately predictive models of catalytic systems that could circumvent energy scaling relations. This work brings the quantum-chemical modeling and machine learning technique together and develops a novel stochastic modeling approach to rationally design the catalysts with desired properties and bridges our knowledge gap between the empirical kinetics and atomistic mechanisms of catalytic reactions.
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Gerdin, Markus. "Identification and Estimation for Models Described by Differential-Algebraic Equations." Doctoral thesis, Linköping : Department of Electrical Engineering, Linköpings universitet, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-7600.
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MARCUCCIO, GABRIELE. "Applications of meta-models, shape descriptor theory and image decomposition to automotive components design and manufacturing variability control." Doctoral thesis, Politecnico di Torino, 2014. http://hdl.handle.net/11583/2574339.
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Camp, John L. "3-D Model Characterization and Identification from Intrinsic Landmarks." Wright State University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=wright1323135521.
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Estrada, Manzo Víctor. "Estimation et commande des systèmes descripteurs." Thesis, Valenciennes, 2015. http://www.theses.fr/2015VALE0032/document.
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Cette thèse est consacrée au développement des techniques d’estimation et de commande pour systèmes descripteurs non linéaires. Les développements sont centrés sur une famille particulière de systèmes descripteurs non linéaires avec une matrice descripteur de rang plein. Toutes les approches présentées utilisent un formalisme de modélisation du type Takagi-Sugeno (TS) pour représenter les modèles descripteurs non linéaires. Un objectif très important est de développer des conditions sous la forme d’inégalités matricielles linéaires (LMI, en anglais). Dans la littérature, les conditions pour l’estimation des modèles TS descripteurs s’écrivent sous forme d’inégalités matricielles bilinéaires (BMI, en anglais). En plus, à notre connaissance, il n’y pas de résultats dans la littérature concernant la commande/estimation pour les modèles TS descripteurs en temps discret (avec une matrice descripteur régulière non linéaire).Trois problèmes ont été examinés : commande par retour d’état, estimation de l’état et commande statique par retour de la sortie. Dans le cas continu, des conditions moins conservatives ont été développées pour la commande par retour d’état. Pour l’estimation d’état, des conditions LMI ont été obtenues (au lieu des usuelles BMI) en utilisant un différent vecteur d’erreur augmenté. Pour la commande statique par retour de la sortie, des conditions LMI sont proposées si une matrice auxiliaire est fixée. Pour le temps discret, des nouveaux résultats sous la forme LMI ont été développées pour la commande/estimation, comblant ainsi certains manques de la littérature. Des exemples ont été inclus pour montrer l’applicabilité de tous les résultats que nous avons obtenus et ainsi l’importance de garder la structure originale des descripteursThis thesis addresses the estimation and control for nonlinear descriptor systems. The developments are focused on a family of nonlinear descriptor models with a full-rank descriptor matrix. The proposed approaches are based on a Takagi-Sugeno (TS) descriptor representation of a given nonlinear descriptor model. This type of TS models is a generalization of the standard TS ones. One of the mains goals is to obtain conditions in terms of linear matrix inequalities (LMIs). In the existing literature, the observer design for TS descriptor models has led to bilinear matrix inequality (BMI) conditions. In addition, to the best of our knowledge, there are no results in the literature on controller/observer design for discrete-time TS descriptor models (with a non-constant and invertible descriptor matrix).Three problems have been addressed: state feedback controller design, observer design, and static output feedback controller design. LMI conditions have been obtained for both continuous and discrete-time TS descriptor models. In the continuous-time case, relaxed LMI conditions for the state feedback controller design have been achieved via parameterdependent LMI conditions. For the observer design, pure LMI conditions have been developed by using a different extended estimation error. For the static output feedback controller, LMI constraints can be obtained once an auxiliary matrix is fixed. In the discretetime case, results in the LMI form are provided for state/output feedback controller design and observer design; thus filling the gap in the literature. Several examples have been included to illustrate the applicability of the obtained results and the importance of keeping the original descriptor structure instead of computing a standard state-space
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Milborrow, Stephen. "Multiview active shape models with SIFT descriptors." Doctoral thesis, University of Cape Town, 2016. http://hdl.handle.net/11427/22867.
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This thesis presents techniques for locating landmarks in images of human faces. A modified Active Shape Model (ASM [21]) is introduced that uses a form of SIFT descriptors [68]. Multivariate Adaptive Regression Splines (MARS [40]) are used to efficiently match descriptors around landmarks. This modified ASM is fast and performs well on frontal faces. The model is then extended to also handle non-frontal faces. This is done by first estimating the face's pose, rotating the face upright, then applying one of three ASM submodels specialized for frontal, left, or right three-quarter views. The multiview model is shown to be effective on a variety of datasets.
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Fröhlich, Kristina, Alexander Pogoreltsev, and Christoph Jacobi. "The 48 Layer COMMA-LIM Model: model description, new aspects, and climatology." Wissenschaftliche Mitteilungen des Leipziger Instituts für Meteorologie ; 30 = Meteorologische Arbeiten aus Leipzig ; 8 (2003), S. 157-185, 2003. https://ul.qucosa.de/id/qucosa%3A15247.
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COMMA-LIM (Cologne Model of the Middle Atmosphere - Leipzig Institute for Meteorology) ist ein 3D-mechanistisches Gitterpuktsmodell, welches sich von ca. 0 bis 135 km in logarhitmischen Druckkordinaten z = -H ln(p=p0) erstreckt, wobei H=7 km und p0 den Referenzdruck am unteren Rand bezeichnet. Die vertikale Auflösung von COMMA-LIM wurde auf 48 Schichten erhöht. Zugleich wurde die Beschreibung
des Strahlungsprozesses verbessert, zusammen mit den Beiträgen zur Temperaturbilanz durch atmosphärische Wellen und Turbulenz. Weitere Veränderungen betreffen die numerische Realisation der horizontalen Diffusion und des Filterproblems. Die Beschreibung ist unterteilt in den dynamischen Teil und die Strahlungsbeträge. Die jahreszeitlichen Klimatologien werden vorgestellt und diskutiert.COMMA-LIM (Cologne Model of the Middle Atmosphere - Leipzig Institute for Meteorology) is a 3D-mechanistic gridpoint model extending up from 0 to 135 km with a logharithmic vertical coordinate z = -H ln(p=p0), where H=7 km and p0 is the reference pressure at lower boundary. The resolution of the 24 layer version has been increased to 48 layers and several improvements are made in the parameterisation of radiative processes, heating/cooling due to atmospheric waves and turbulence, as well as in the numerical realization of the horizontal diffusion and filtering. This description is divided into the section describing the changes in the dynamical part and the modifications in radiation routines. After all, the seasonal climatologies will be shown and discussed to demonstrate what the COMMA-LIM is capable of reproducing.
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Preacher, Kristopher J. "The Role of Model Complexity in the Evaluation of Structural Equation Models." The Ohio State University, 2003. http://rave.ohiolink.edu/etdc/view?acc_num=osu1054130634.
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Wright, Philip A. "Rapid development of VHDL behavioral models." Thesis, This resource online, 1992. http://scholar.lib.vt.edu/theses/available/etd-11102009-020056/.
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Ilg, Patrick Ilg Patrick Ilg Patrick Ilg Patrick. "Reduced description of kinetic models of polymer dynamics /." [S.l.] : [s.n.], 2001. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=14256.
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Pooley, R. J. "Formalising the description of process based simulation models." Thesis, University of Edinburgh, 1995. http://hdl.handle.net/1842/11271.
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Discrete event simulation has grown up as a practical technique for estimating the quantitative behaviour of systems, where direct measurement is undesirable or impractical. It is also used to understand the detailed behaviour of such systems. Its theory is largely that of experimental science. Theories of simulation largely centre on statistical approaches to validating the measures generated by models, rather than on the verification of their detailed behaviour. This dissertation presents an approach to understanding the correctness of the behaviour of discrete event simulation models, using Milner's Calculus of Communicating Systems (CCS). It is shown that a framework based on the process view of models can be constructed for hierarchical modelling, where both performance and functional properties are of interest. As a formal basis for this framework, a hierarchical graphical modelling language (Extended Activity Diagrams) is developed. A semantics is developed for this language, in terms of CCS. This language is shown to map onto the major constructs of the DEMOS discrete event simulation language, extended to allow hierarchical modelling and to resolve certain ambiguities. The result is a new version of DEMOS known as modified DEMOS. A graphically driven tool based on such a framework is presented. It allows modellers to use a combination of simulation and functional techniques to answer both performance questions (what is the throughput under a certain load) and functional questions (will the system deadlock under certain assumptions). In particular this tool can support process oriented simulations of models, using modified DEMOS, and functional analysis, based on both the basic version and the timed extension of Milner's Calculus of Communicating Systems and using the Concurrency Workbench. A number of examples of interesting applications of this approach to typical models are presented.
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Schmitt, Miriam. "Microscopic description of magnetic model compounds." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2013. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-110282.
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Solid state physics comprises many interesting physical phenomena driven by the complex interplay of the crystal structure, magnetic and orbital degrees of freedom, quantum fluctuations and correlation. The discovery of materials which exhibit exotic phenomena like low dimensional magnetism, superconductivity, thermoelectricity or multiferroic behavior leads to various applications which even directly influence our daily live. For such technical applications and the purposive modification of materials, the understanding of the underlying mechanisms in solids is a precondition. Nowadays DFT based band structure programs become broadly available with the possibility to calculate systems with several hundreds of atoms in reasonable time scales and high accuracy using standard computers due to the rapid technical and conceptional development in the last decades. These improvements allow to study physical properties of solids from their crystal structure and support the search for underlying mechanisms of different phenomena from microscopic grounds.
This thesis focuses on the theoretical description of low dimensional magnets and intermetallic compounds. We combine DFT based electronic structure and model calculations to develop the magnetic properties of the compounds from microscopic grounds. The developed, intuitive pictures were challenged by model simulations with various experiments, probing microscopic and macroscopic properties, such as thermodynamic measurements, high field magnetization, nuclear magnetic resonance or electron spin resonance experiments. This combined approach allows to investigate the close interplay of the crystal structure and the magnetic properties of complex materials in close collaboration with experimentalists. In turn, the systematic variation of intrinsic parameters by substitution or of extrinsic factors, like magnetic field, temperature or pressure is an efficient way to probe the derived models. Especially pressure allows a continuous change of the crystal structure on a rather large energy scale without the chemical complexity of substitution, thus being an ideal tool to consistently alter the electronic structure in a controlled way. Our theoretical results not only provide reliable descriptions of real materials, exhibiting disorder, partial site occupation and/or strong correlations, but also predict fascinating phenomena upon extreme conditions. In parts this theoretical predictions were already confirmed by own experiments on large scale facilities.
Whereas in the first part of this work the main purpose was to develop reliable magnetic models of low dimensional magnets, in the second part we unraveled the underlying mechanism for different phase transitions upon pressure. In more detail, the first part of this thesis is focused on the magnetic ground states of spin 1/2 transition metal compounds which show fascinating phase diagrams with many unusual ground states, including various types of magnetic order, like helical states exhibiting different pitch angles, driven by the intimate interplay of structural details and quantum fluctuations. The exact arrangement and the connection of the magnetically active building blocks within these materials determine the hybridization, orbital occupation, and orbital orientation, this way altering the exchange paths and strengths of magnetic interaction within the system and consequently being crucial for the formation of the respective ground states. The spin 1/2 transition metal compounds, which have been investigated in this work, illustrate the great variety of exciting phenomena fueling the huge interest in this class of materials.
We focused on cuprates with magnetically active CuO4 plaquettes, mainly arranged into edge sharing geometries. The influence of structural peculiarities, as distortion, folding, changed bonding angles, substitution or exchanged ligands has been studied with respect to their relevance for the magnetic ground state. Besides the detailed description of the magnetic ground states of selected compounds, we attempted to unravel the origin for the formation of a particular magnetic ground state by deriving general trends and relations for this class of compounds. The details of the treatment of the correlation and influence of structural peculiarities like distortion or the bond angles are evaluated carefully.
In the second part of this work we presented the results of joint theoretical and experimental studies for intermetallic compounds, all exhibiting an isostructural phase transition upon pressure. Many different driving forces for such phase transitions are known like quantum fluctuations, valence instabilities or magnetic ordering. The combination of extensive computational studies and high pressure XRD, XAS and XMCD experiments using synchrotron radiation reveals completely different underlying mechanism for the onset of the phase transitions in YCo5, SrFe2As2 and EuPd3Bx.
This thesis demonstrates on a series of complex compounds that the combination of ab-initio electronic structure calculations with numerical simulations and with various experimental techniques is an extremely powerful tool for a successful description of the intriguing quantum phenomena in solids. This approach is able to reduce the complex behavior of real materials to simple but appropriate models, this way providing a deep understanding for the underlying mechanisms and an intuitive picture for many phenomena. In addition, the close interaction of theory and experiment stimulates the improvement and refinement of the methods in both areas, pioneering the grounds for more and more precise descriptions. Further pushing the limits of these mighty techniques will not only be a precondition for the success of fundamental research at the frontier between physics and chemistry, but also enables an advanced material design on computational grounds.
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Abdurahiman, Vakulathil. "Towards inducing a simulation model description." Thesis, Brunel University, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.239138.
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Piro, Robert. "Model-theoretic characterisations of description logics." Thesis, University of Liverpool, 2012. http://livrepository.liverpool.ac.uk/9317/.
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The growing need for computer aided processing of knowledge has led to an increasing interest in description logics (DLs), which are applied to encode knowledge in order to make it explicit and accessible to logical reasoning. DLs and in particular the family around the DL ALC have therefore been thoroughly investigated w.r.t. their complexity theory and proof theory. The question arises which expressiveness these logics actually have. The expressiveness of a logic can be inferred by a model theoretic characterisation. On concept level, these DLs are akin to modal logics whose model theoretic properties have been investigated. Yet the model theoretic investigation of the DLs with their TBoxes, which are an original part of DLs usually not considered in context of modal logics, have remained unstudied. This thesis studies the model theoretic properties of ALC, ALCI, ALCQ, as well as ALCO, ALCQO, ALCQIO and EL. It presents model theoretic properties, which characterise these logics as fragments of the first order logic (FO). The characterisations are not only carried out on concept level and on concept level extended by the universal role, but focus in particular on TBoxes. The properties used to characterise the logics are `natural' notions w.r.t. the logic under investigation: On the concept-level, each of the logics is characterised by an adapted form of bisimulation and simulation, respectively. TBoxes of ALC, ALCI and ALCQ are characterised as fragments of FO which are invariant under global bisimulation and disjoint unions. The logics ALCO, ALCQO and ALCQIO, which incorporate individuals, are characterised w.r.t. to the class K of all interpretations which interpret individuals as singleton sets. The characterisations for TBoxes of ALCO and ALCQO both require, additionally to being invariant under the appropriate notion of global bisimulation and an adapted version of disjoint unions, that an FO-sentence is, under certain circumstances, preserved under forward generated subinterpretations. FO-sentences equivalent to ALCQIO-TBoxes, are - due to ALCQIO's inverse roles - characterised similarly to ALCO and ALCQO but have as third additional requirement that they are preserved under generated subinterpretations. EL as sub-boolean DL is characterised on concept level as the FO-fragment which is preserved under simulation and preserved under direct products. Equally valid is the characterisation by being preserved under simulation and having minimal models. For EL-TBoxes, a global version of simulation was not sufficient but FO-sentences of EL-TBoxes are invariant under global equi-simulation, disjoint unions and direct products. For each of these description logics, the characteristic concepts are explicated and the characterisation is accompanied by an investigation under which notion of saturation the logic in hand enjoys the Hennessy-and-Milner-Property. As application of the results we determine the minimal globally bisimilar companion w.r.t. ALCQO-bisimulation and introduce the L1-to-L2-rewritability problem for TBoxes, where L1 and L2 are (description) logics. The latter is the problem to decide whether or not an L1-TBox can be equivalently expressed as L2-TBox. We give algorithms which decide ALCI-to-ALC-rewritability and ALC-to-EL-rewritability.
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Hossain, Mohammad Sahadet. "Numerical Methods for Model Reduction of Time-Varying Descriptor Systems." Doctoral thesis, Universitätsbibliothek Chemnitz, 2011. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-74776.
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This dissertation concerns the model reduction of linear periodic descriptor systems both in continuous and discrete-time case. In this dissertation, mainly the projection based approaches are considered for model order reduction of linear periodic time varying descriptor systems. Krylov based projection method is used for large continuous-time periodic descriptor systems and balancing based projection technique is applied to large sparse discrete-time periodic descriptor systems to generate the reduce systems.
For very large dimensional state space systems, both the techniques produce large dimensional solutions. Hence, a recycling technique is used in Krylov based projection methods which helps to compute low rank solutions of the state space systems and also accelerate the computational convergence. The outline of the proposed model order reduction procedure is given with more details. The accuracy and suitability of the proposed method is demonstrated through different examples of different orders.
Model reduction techniques based on balance truncation require to solve matrix equations. For periodic time-varying descriptor systems, these matrix equations are projected generalized periodic Lyapunov equations and the solutions are also time-varying. The cyclic lifted representation of the periodic time-varying descriptor systems is considered in this dissertation and the resulting lifted projected Lyapunov equations are solved to achieve the periodic reachability and observability Gramians of the original periodic systems. The main advantage of this solution technique is that the cyclic structures of projected Lyapunov equations can handle the time-varying dimensions as well as the singularity of the period matrix pairs very easily. One can also exploit the theory of time-invariant systems for the control of periodic ones, provided that the results achieved can be easily re-interpreted in the periodic framework.
Since the dimension of cyclic lifted system becomes very high for large dimensional periodic systems, one needs to solve the very large scale periodic Lyapunov equations which also generate very large dimensional solutions. Hence iterative techniques, which are the generalization and modification of alternating directions implicit (ADI) method and generalized Smith method, are implemented to obtain low rank Cholesky factors of the solutions of the periodic Lyapunov equations. Also the application of the solvers in balancing-based model reduction of discrete-time periodic descriptor systems is discussed. Numerical results are given to illustrate the effciency and accuracy of the proposed methods.
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Benn, David E. "Model-based feature extraction and classification for automatic face recognition." Thesis, University of Southampton, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.324811.
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Kiernan, Patrick James. "Models of conversation and narrative : towards a pedagogical description." Thesis, University of Birmingham, 2008. http://etheses.bham.ac.uk//id/eprint/170/.
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This is the first of three modules concerned with narrative and identity in English language teaching in Japan. This module makes the case for developing a pedagogical model of spoken discourse, particularly spoken narrative, to aid the teaching of English in foreign language contexts such as Japan. It is proposed that this model should take account of the learners L1, in this case Japanese. Rather than teaching the model, however, it is suggested that the model would ideally be applied using a task-based approach.
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Ardeishar, Raghu. "Automatic verification of VHDL models." Thesis, This resource online, 1990. http://scholar.lib.vt.edu/theses/available/etd-03032009-040338/.
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Chadha, Vikrampal. "Simulation of large-scale system-level models." Thesis, This resource online, 1994. http://scholar.lib.vt.edu/theses/available/etd-12162009-020334/.
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Scheithauer, Gregor [Verfasser] [Akademischer Betreuer]. "A Service Description Method for Service Ecosystems - Meta Models, Modeling Notations, and Model Transformations / Gregor Scheithauer. Betreuer: Gregor Scheithauer." Bamberg : Universitätsbibliothek der Universität Bamberg, 2011. http://d-nb.info/1014896738/34.
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Köhler, Marcus. "Linklets - Formal Function Description and Permission Model." Master's thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2012. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-83380.
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Linklets are location-independent web services, which consume and produce Linked Data resources. These resources form a web of data - the semantic web - that is an abstraction of the web 2.0. However, enterprises are reluctant to provide valuable Linked Data resources due to missing financial stimuli. Operations are not representable in the semantic web.
Linklets aim to solve both problems. Previous work developed a prototype. The goal of this thesis is to enhance it by a component model, a formal description and a permission model. A business model has to be developed.
This thesis follows a bottom-up approach. The formalization of the Linklet concept creates a foundation. Then, an improved architecture and its reference implementation are studied. It is evaluated by tests, show cases and economic considerations.
The resulting component system is based on web-service component systems, while a sandbox concept is the core of the permission model. The formal description shows limits of OWLs open world assumption. A platform leader strategy is the foundation for the business model.
In conclusion, the advantages of the Linklet concept provide a way to enhance and monetize the value of the semantic web. Further research is required; the practical use has to be considered.
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Björkholm, Patrik. "Method for recognizing local descriptors of protein structures using Hidden Markov Models." Thesis, Linköping University, The Department of Physics, Chemistry and Biology, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-11408.
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Being able to predict the sequence-structure relationship in proteins will extend the scope of many bioinformatics tools relying on structure information. Here we use Hidden Markov models (HMM) to recognize and pinpoint the location in target sequences of local structural motifs (local descriptors of protein structure, LDPS) These substructures are composed of three or more segments of amino acid backbone structures that are in proximity with each other in space but not necessarily along the amino acid sequence. We were able to align descriptors to their proper locations in 41.1% of the cases when using models solely built from amino acid information. Using models that also incorporated secondary structure information, we were able to assign 57.8% of the local descriptors to their proper location. Further enhancements in performance was yielded when threading a profile through the Hidden Markov models together with the secondary structure, with this material we were able assign 58,5% of the descriptors to their proper locations. Hidden Markov models were shown to be able to locate LDPS in target sequences, the performance accuracy increases when secondary structure and the profile for the target sequence were used in the models.
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MOREIRA, ANDRE DE SOUZA. "REVERSE ENGINEERING FOR CAD MODELS USING SHAPE DESCRIPTORS AND SUPPORT VECTOR MACHINE." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2015. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=25821@1.
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PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIROCONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO
Modelos CAD 3D têm desempenhado um importante papel no gerenciamento de projetos de engenharia. Em vários desses modelos é perceptível a presença de diversos objetos com representações implícitas sendo representados por malhas triangulares. Ainda que apropriada para o rendering, a utilização de malhas triangulares traz consigo algumas desvantagens, como a ambiguidade em objetos pouco discretizados. A engenharia reversa visa a reconstrução dessa representação discreta em sua representação contínua original. Neste trabalho, propomos uma metodologia para a reconstrução de geometrias em modelos CAD utilizando Support Vector Machines e Descritores de Forma.
3D CAD Models have played an important role in engineering projects management. It is noticeable in many of these files the presence of several objects with implicit representation that end up being represented as triangular meshes. Although suitable for rendering, the triangular mesh representation brings some drawbacks, such as the ambiguity in objects with low discretization rate. The reverse engineering aims to reconstruct this discrete representation to its original continuous representation. In this work, we propose a novel methodology for geometry reconstruction in CAD models using Support Vector Machines and Shape Descriptors.
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Fard, Ali Ataei. "Room Function Program and Technical Description : Interaction with BIM Models." Thesis, Mittuniversitetet, Avdelningen för informations- och kommunikationssystem, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-29969.
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The move from two dimensional drawings (2D) to three dimensional (3D) models is underway in the architectural, engineering and construction industry. The three dimensional models may also be full of information which more exactly defines the different elements of a building, such models are called Building Information Modelling (BIM). Normally within a construction project, Computer-Aided Design (CAD) tools, experts add information to models and the feedback from the rest of the stakeholders are done during common meetings. The important part of information management of construction projects is the briefing process, collecting and defining the client's requirements throughout the construction project. The thesis project aims at defining and developing such tools which communicates with BIM models. Specifically, the main focus of this thesis is on creating interactive tools for Room Function Program (RFP) and Technical Description. An RFP describes the content and functionality of one or several rooms of a building that is designed at the early stage of a building construction. A Technical Description defines and describes all specifications of products which should be in a building. Current available and commonly used processes and products for RFP will be examined within this thesis as the industry has room for improvements with these particular concepts. The thesis project is conducted through research, case studies and interviews, respectively. First, the research and case studies analyzed the use and benefits of BIM. Then, the interview examined the gap between BIM, RFP and Technical Description and it is included in Appendix A. Subsequently, the RFP and Technical Description tools will be integrated with the BIM viewer successfully and desired visual feedback is given by filtering and highlighting the object in the model.
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Thadani, Sunil. "Constructing functional models of a device from its structural description /." The Ohio State University, 1994. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487854314873138.
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Calhoun, Karen. "Redesign of Library Workflows: Experimental Models for Electronic Resource Description." the Library of Congress, 2000. http://hdl.handle.net/10150/105094.
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This paper explores the potential for and progress of a gradual transition from a highly centralized model for cataloging to an iterative, collaborative, and broadly distributed model for electronic resource description. The author's purpose is to alert library managers to some experiments underway and to help them conceptualize new methods for defining, planning, and leading the e-resource description process under moderate to severe time and staffing constraints. To build a coherent library system for discovery and retrieval of networked resources, librarians and technologists are experimenting with team-based efforts and new workflows for metadata creation. In an emerging new service model for e-resource description, metadata can come from selectors, public service librarians, information technology staff, authors, vendors, publishers, and catalogers. Arguing that e-resource description demands a level of cross-functional collaboration and creative problem-solving that is often constrained by libraries' functional organizational structures, the author calls for reuniting functional groups into virtual teams that can integrate the e-resource description process, speed up operations, and provide better service. The paper includes an examination of the traditional division of labor for producing catalogs and bibliographies, a discussion of experiments that deploy a widely distributed e-resource description process (e.g., the use of CORC at Cornell and Brown), and an exploration of the results of a brief study of selected ARL libraries' e-resource discovery systems.
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Rao, Sanat R. "A hierarchical approach to effective test generation for VHDL behavioral models." Thesis, This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-08042009-040513/.
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Srihi, Hajer. "Stratégies de stabilité en position assise chez les personnes vivant avec une lésion de la moelle épinière : de l’estimation utilisant des modèles descripteurs quasi-LPV à la validation expérimentale." Electronic Thesis or Diss., Valenciennes, Université Polytechnique Hauts-de-France, 2023. http://www.theses.fr/2023UPHF0041.
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La lésion médullaire conduit à une perte partielle ou complète de l’activité musculaire et des fonctions sensorielles en dessous du niveau lésionnel, cette atteinte de la moelle épinière entraîne une réduction drastique de la stabilité posturale en position assise et par conséquent un risque de chute élevé (Boswell-Ruys et al., 2010 ; Nelson et al., 2010).Les conséquences de la lésion médullaire sont importantes et d’ordre sensori-motrices, cardio-vasculaires, respiratoires et digestives. L’impact de la lésion sur le système stabilisateur vertébral conduit à de nouvelles stratégies de stabilisation, en cas de perturbation, qui sont différentes des stratégies mise en œuvre par les sujets asymptomatiques. Ces stratégies qui viennent compenser l’absence d'un contrôle sous-lésionnel sont basées essentiellement sur les mouvements des membres supérieurs.La compréhension de ces stratégies ainsi que la quantification des efforts articulaires qui en résultent sont nécessaires afin d’évaluer l’impact de la lésion et proposer des nouvelles techniques facilitant le maintien de la stabilité. L’un des enjeux est de savoir « retourner » vers les variables qui génèrent ces efforts, les couples articulaires, données qui ne sont pas mesurées et ne sont pas mesurables. Une manière de le faire, alternative à la « classique » dynamique inverse, a été exploitée dans les travaux précédents (Blandeau, 2018). Elle consiste, à partir d’un modèle biomécanique, à utiliser des techniques d’observation pour reconstruire ces entrées inconnues. Le formalisme utilisé est un formalisme dit de Takagi-Sugeno qui permet de décrire de façon polytopique des systèmes non linéaires. La description utilisée est de type descripteur, car elle se prête bien aux modèles mécaniques en diminuant la complexité des conditions obtenues (Estrada-Manzo, 2015).Une campagne d’essais réalisée au CRIR de Montréal (Blandeau, 2018) a permis de recueillir de nombreuses données sur la posture assise des personnes lésées médullaires. Seule une partie de ces essais a pu être exploitée car le modèle « Seated-3-segments » (S3S) utilisé ne permettait pas de décrire toutes les situations rencontrées, par exemple une dissymétrie dans les mouvements des bras.Il y a plusieurs challenges :Enrichir les modèles existants, notamment le modèle S3S (Blandeau, 2018) sachant qu’une résolution « directe » avec un observateur issu de ce type de modèle est déjà proche des limitations des solveurs actuels.Arriver à des solutions qui sont pertinentes (a minima qui utilisent les modèles biomécaniques sans simplification), compatibles avec les possibilités des solveurs et suffisamment génériques pour ne pas demander de refaire une étude complète si on ajoute des degrés de liberté supplémentaires.Dans l’esprit de ces challenges, des propositions d’observateurs non linéaires mis en cascade sont faites. Pour montrer le bien-fondé de l’approche, les résultats sont d’abord comparés à l’existant (S3S) avant d’être étendus à des modèles utilisant des degrés de liberté supplémentaires dont « Trunk-2-arms » (T2A) pour lesquels la méthodologie précédente ne peut apporter de solutions. T2A permet notamment d’exploiter des essais impliquant une dissymétrie dans les mouvements de membres supérieurs. Il reste dans les étapes suivantes à introduire les rotations, notamment au niveau des épaules pour se rapprocher des mouvements réels effectués par le sujet. La méthodologie utilisée semble parfaitement adaptée pour réaliser cette extension.Enfin, un mannequin équipé de tous les actionneurs et capteurs nécessaires permettant de reproduire les mouvements d’une personne en position assise sera utilisé avec cette fois-ci la possibilité de valider les couples articulaires reconstruits, en les comparant directement à ceux produitsSpinal cord injury leads to a partial or complete loss of muscular activity and sensory functions below the level of injury, this damage to the spinal cord leads to a drastic reduction in postural stability in a sitting position and consequently a high risk of falling (Boswell-Ruys et al., 2010; Nelson et al., 2010).The consequences of the injury are significant and are sensorimotor, cardiovascular, respiratory and digestive. The impact of the injury on the vertebral stabilizing system leads to new stabilization strategies, in case of disturbance, which are different from the strategies implemented by asymptomatic subjects. These strategies, which compensate for the lack of sublesionel control, are essentially based on the movements of the upper limbs.Understanding these strategies as well as quantifying the resulting joint forces are necessary in order to assess the impact of the injury and propose news methods facilitating the control of seated stability.One of the challenges is knowing how to ‘’return’’ to the variables that generate these efforts, the joint torques, data which are not measured and cannot be measured. A way of doing that, an alternative to the ‘’classic’’ inverse dynamics, has been exploited in previous work (Blandeau, 2018). It consists, from a biomechnical model, of using observation techniques to reconstruct these unknown inputs. The formalism used is a so-called Takagi-Sugeno formalism in order to describe nonlinear systems in a polytopic manner. The description used is of descriptor type, because it lends itself well to mechanical models by reducing the complexity of the conditions obtained (Estrada-Manzo, 2015).A test compaign carried out at the CRIR in Montreal (Blandeau, 2018) made it possible to collect numerous data on the sitting posture of people with spinal cord injuries. Only part of these tests could be analyzed because the ‘’Seated-3-Segments’’ (S3S) model used is not able to describe all the situations encountered, for example asymmetry in arm movements.There are several challenges:Enriching existing models, in particular the S3S model (Blandeau, 2018), knowing that the ‘’direct’’ resolution with an observer from this type of model is already close to the limitations of current solvers.Arrive at solutions which are relevant (at a minimum which use biomechanical models without simplification), compatible with the possibilities of the solvers and sufficiently generic so are not to require redoing a complete study if additional degrees of freedom are added. To fulfil these challenges, proposals for cascaded nonlinear observers are made. To show the merits of the approach, the results are first compared to the existing one (S3S) before being extended to models using additional degrees of freedom including ‘’Trunk-2-Arms’’ (T2A) for which the previous methodology cannot provide solutions. T2A make it possible in particular to exploit tests involving asymmetry in upper limbs movements. In the following stages, it remains to introduce rotations, particularly at the level of the shoulders to approximate the real movements carried out by the subject. The methodology used seems perfectly suited to carry out this extension.Finally, a mannequin equipped with all the necessary actuators and sensors to reproduce the movements of a person in seated position will be used, this time with the possibility of validating the reconstructed joint torques, by directly comparing them to those produced
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Blanckenberg, Jacobus Petrus. "Skyrme model description of heavy baryons with strangeness." Thesis, Stellenbosch : Stellenbosch University, 2015. http://hdl.handle.net/10019.1/96953.
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Shamardin, A. V. "Exchange anisotropy: phenomenological description and a simple model." Thesis, Sumy State University, 2015. http://essuir.sumdu.edu.ua/handle/123456789/40676.
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One of the key components in GMR materials , magnetic tunnel junctions or other electromagnetic devices is often an antiferromagnetic (AF) layer which is exchangecoupled to a ferromagnetic (F) layer. The function of the AF layer is to pin the magnetization direction of the adjacent F layer to a certain direction. The most prominent manifestation of the F/AF exchange interaction is a shift of the hysteresis loop of the F layer along the field axis, as if an additional fixed external field is applied to the F layer. This effective magnetic field is called the exchange bias field, H. The direction of this effective field is called the exchange bias direction. In contrast to the ferromagnetocrystalline anisotropy of a homogeneous magnet, which is characterized by easy and hard axes, exchange anisotropy is characterized by a single easy direction. It is called uniaxial anisotropy.
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Loizillon, Guillaume. "Modes de description des sons et synthese sonore." Paris 8, 1996. http://www.theses.fr/1996PA081164.
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Le son est defini comme la conjonction d'un phenomene physique et d'une realite physiologique et psychologique. Pourtant, seule la perception auditive fonde le phenomene acoustique dans sa specificite sonore. La mise en parallele des grandeurs physiques avec les donnees du sens de l'ouie est une conception limitee. Les travaux avances en psycho-acoustique montrent que l'audition ne peut se resumer en l'etablissement de ce reseau. Il faut considerer les sons comme les composantes d'une scene auditive dont la musique est un modele particulier. Il devient alors necessaire d'analyser les specificites du son musical, en suivant les etapes historiques qui ont conduit a une definition de celui-ci, articulee sur les parametres de hauteur, de duree d'intensite et de timbre. Cette derniere composante apparait comme valeur centrale dans la musique contemporaine. Ce basculement d'une musique des hauteurs vers une musique du timbre, prend un caractere decisif avec l'apparition des techniques electriques du son. En un siecle, elles ont apporte au musicien une panoplie d'outils qui utilisent les virtualites du son transforme en electricite, puis en informations numeriques. Au sein de ces nouvelles ressources, la seconde partie du travail se consacre a la synthese sonore. Sont abordes les differents modes de synthese sonore a travers un ensemble d'exemples sonores realises avec deux categories de programmes: les modes de synthese de signal, ou l'on specifie les differentes parametres de l'onde acoustique. Les modes de synthese par modeles physiques ou l'on decrit l'interaction entre differents objets modelises : cordes, plaques, plectres, anches. . . Par-dela la mise en oeuvre de processus techniques, l'objectif de ce travail est de demontrer que l'activite de synthese sonore est un veritable enjeu pour la composition qu'il serait une erreur de penser comme un seul produit de la technologieSOUND IS DEFINED AS THE JUNCTION BETWEEN A PHYSICAL PHENOMENON AND PHYSIOLOGICAL A PSYCHOLOGICAL REALITY. MEANWHILE, ONLY THE AUDITIVE PERCEPTION - ESTABLISHES ACOUSTIC PHENOMENON ITS SOUNDING SPECIFICITY. LINKING PHYSICAL DIMENSIONS WITH ELEMENTS OF HEARING IS A RESTRICTED IDEA. LEADING WORKS IN PSYCHOACOUSTIC SHOW THAT AUDITION CANNOT BE REDUCED TO THIS CONCEPT. SOUNDS HAVE TO BE CONSIDERED AS THE ELEMENTS OF AN AUDITION SCENE OF WHICH MUSIC IS A SPECIFIC CASE. THUS, IT IS NECESSARY TO ANALYSE SPECIFICITIES OF MUSICAL SOUND, FOLLOWING THE HISTORICAL WAY THAT LEAD TO A DEFINITION ARTICULATED AROUND PARAMETERS OF PITCH, DURATION, INTENSITY AND TIMBRE. THIS LAST DIMENSION APPEARS AS A CENTRAL VALUE IN CONTEMPORARY MUSIC. THIS TRANSITION FROM A MUSIC OF PITCH TO A MUSIC OF TIMBRE, TAKES A DECISIVE DIMENSION with THE BIRTH OF ELECTRICAL SOUND TECHNICS. IN THE TIME OF ONE CENTURY THOSE TECHNICS BROUGHT MUSICIANS A COLLECTION OF TOOLS THAT USES THE CAPACITIES OF SOUND TRANSFORMED IN ELECTRICITY THEN IN DIGITAL INFORMATION. AMONG THOSE RESSOURCES, THE SECOND PART OF THIS WORK TAKES SOUND SYNTHESIS AS SUBJECT. WE DISCUSS IN THIS PART OF DIFFERENT SYNTHESIS METHODS AND WE SHOW DIFFERENT PROGRAMMING EXAMPLES, SEPARATED IN TWO CATEGORIES. METHODS OF SIGNAL SYNTHESIS IN WHICH ALL THE PARAMETERS OF ACOUSTIC WAVES MUST BE SPECIFIED. PHYSICAL MODELING WHERE THE INTERACTION BETWEEN OBJECTS LIKE STRING, PLATE, TUBE, MASS, IS DESCRIBED BEYOND A TECHNICAL PROCESS, THE GOAL OF THIS WORK IS TO DEMONSTRATE THAT SOUND SYNTHESIS IS A GENUINE PART OF MUSICAL COMPOSITION TERRITORY. IT WOULD BE A MISTAKE TO REGARD ONLY AS A TECHNOLOGICAL PRODUCT
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Gunderson, Steinar Heimdal. "Musical descriptors : An assessment of psychoacoustical models in the presence of lossy compression." Thesis, Norwegian University of Science and Technology, Department of Electronics and Telecommunications, 2007. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-9524.
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A simple system for recognizing music is presented, based on various musical descriptors, numbers that describe some aspect of the music. Various descriptors are discussed; in particular, a novel descriptor, the floor-1 cepstral coefficient (F1CC) measure, a refinement of MFCCs based on the Vorbis psychoacoustical model is presented and evaluated. Also, various forms of statistical dimensionality reduction, among them PCA and LDA, are considered in the present context. Finally, a few directions for future work are discussed.
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Gadagkar, Ashish. "Timing distribution in VHDL behavioral models." Thesis, This resource online, 1992. http://scholar.lib.vt.edu/theses/available/etd-10102009-020318/.
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Pan, Bi-Yu. "Hierarchical test generation for VHDL behavioral models." Thesis, This resource online, 1992. http://scholar.lib.vt.edu/theses/available/etd-09052009-040449/.
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Zamora, Ramírez William J. "Toward Refined Theoretical Models for the Description of Lipophilicity in Biomolecules." Doctoral thesis, Universitat de Barcelona, 2019. http://hdl.handle.net/10803/666014.
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Lipophilicity is a key physicochemical descriptor used to understand the biological profile of (bio)organic compounds, xenobiotics and a broad variety of biochemical, pharmacological, and toxicological processes. This property is estimated from the partition coefficient between aqueous and nonaqueous environments for neutral compounds (PN) and corrected for the pH- dependence of ionizable compounds as the distribution coefficient (D). In this context, in this doctoral thesis the Miertus–Scrocco–Tomasi continuum solvation model was used to check the suitability of some reported and proposed formalisms to estimate the distribution coefficient for a set of small acidic and basic compounds. The results indicate that in general the simple pH- dependence model of the ionizable compound in water suffices to predict the partitioning at or around physiological pH. However, at extreme pH values, where ionic species are predominant, more elaborate models provide a better prediction of pH-dependent distribution curves of log D for both acidic and basic compounds as well as for amino acid analogues. New theoretical treatments for the lipophilicity profile of ionizable compounds were proposed to account for the electroneutrality in the phases of the n-octanol/water system. In this context, was used the theory of ion-transfer across the interface between two immiscible electrolyte solutions (ITIES). Experimental research is being carried out to see the scope of those formalisms developed in this thesis.
Taking advantage of the successful results in small compounds, a lipophilicity scale adapted to different pH conditions was built for the 20 natural amino. The environment-dependence was introduced from the Dunbrack’s backbone- dependent conformational library using two weighting schemes for the rotamers: solvent-like (SolvL) and protein-like (ProtL) lipophilic schemes. The veracity of our scale was corroborated with successful correlations with other consolidated experimental scales. Characterization of short disordered peptides (retention times in RP-HPLC, log PN and log D7.4 values) was best described using the former approach, and biological properties of peptides with available three-dimensional structure (local context-dependent lipophilicity e.g binding free energies) with the second one. Our theoretical lipophilicity scale was thus characterized by its versatility and adaptability, which confers a unifying character. Future studies will address the application of this methodology to the calculation of lipophilic parameters for no proteogenic amino acids, other conformations of the actual residues (proline cis) and other fragments relevant to proteins. On the other hand, the applicability of the present versatile scale is vast and promising, including for instance the use as scorings for protein- protein docking protocols, among others.La lipofilicidad es un descriptor fisicoquímico clave utilizado para comprender el perfil biológico de los compuestos (bio)orgánicos, xenobióticos y una amplia variedad de procesos bioquímicos, farmacológicos y toxicológicos. Esta propiedad se estima a partir del coeficiente de reparto entre ambientes acuosos y no acuosos para compuestos neutros (PN) y corregido para la dependencia del pH de los compuestos ionizables como el coeficiente de distribución (D). En este contexto, en esta tesis doctoral se usó el modelo de solvatación continua de Miertus-Scrocco-Tomasi para verificar la idoneidad de algunos formalismos reportados y propuestos para estimar el coeficiente de distribución para un conjunto de pequeños compuestos ácidos y básicos. Los resultados indican que, en general, el modelo simple de dependencia del pH del compuesto ionizable en agua es suficiente para predecir la partición en o alrededor del pH fisiológico. Sin embargo, a valores extremos de pH, donde predominan las especies iónicas, los modelos más elaborados proporcionan una mejor predicción de las curvas de distribución dependientes del pH del log D, tanto para compuestos ácidos como básicos, así como para análogos de aminoácidos. Se propusieron nuevos tratamientos teóricos para el perfil de lipofilicidad de compuestos ionizables para explicar la electroneutralidad en las fases del sistema n-octanol/agua. En este contexto, se utilizó la teoría de la transferencia de iones a través de la interfase entre dos disoluciones de electrólitos inmiscibles (ITIES por sus siglas en inglés). Se están llevando a cabo investigaciones experimentales para ver el alcance de los formalismos desarrollados en esta tesis. Aprovechando los resultados exitosos en pequeños compuestos, se construyó una escala de lipofilicidad adaptada a diferentes condiciones de pH para los 20 aminoácidos naturales. La dependencia del entorno se introdujo a partir de la biblioteca conformacional dependiente del “backbone” de Dunbrack utilizando dos esquemas de ponderación para los rotámeros: el esquema lipofílico tipo solvente (SolvL) y tipo proteíco (ProtL). La veracidad de nuestra escala se corroboró con correlaciones exitosas con otras escalas experimentales ya consolidadas. La caracterización de péptidos cortos desordenados (valores de tiempos de retención en “RP-HPLC”, log PN y log D7.4) fue mejor descrita utilizando el primer esquema, y las propiedades biológicas de los péptidos con estructura tridimensional disponible (lipofilicidad dependiente del contexto local y energías libres de unión) con la segunda. Nuestra escala teórica de lipofilicidad se caracterizó por su versatilidad y adaptabilidad, lo que le confiere un carácter unificador. Los estudios futuros abordarán la aplicación de esta metodología al cálculo de parámetros lipofilicos para aminoácidos no proteogénicos, otras conformaciones de los residuos actuales (prolina cis) y otros fragmentos relevantes para las proteínas. Por otro lado, la aplicabilidad de la escala versátil actual es amplia y prometedora, incluyendo, por ejemplo, el uso como ponderantes para protocolos de acoplamiento de proteína-proteína, entre otros.
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Sitepu, Husinsyah. "March-type models for the description of texture in granular materials." Thesis, Curtin University, 1998. http://hdl.handle.net/20.500.11937/2314.
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Texture in crystalline materials, i.e. preferred orientation (PO), is of interest in terms of texture-property relationships and also in X-ray diffraction science because PO can cause serious systematic errors in quantitative phase analysis using diffraction data. The single- parameter, pole-density distribution function (PDDF), proposed by March (1932) to represent PO in diffraction analysis, is used widely it Rietveld pattern-fitting following a suggestion by Dollase (1986). While the March model is an excellent descriptor of PO for gibbsite [AI(OH)3] x-ray powder diffraction (XRPD) data (O'Connor, Li and Sitepu, 1991), the model has proved to be deficient for Rietveld modelling with molybdite [Mo03], calcite [CaCO3] and kaolinite [A12O3.2SiO2.2H2O] XRPD data (Sitepu, 1991; O'Connor, Li and Sitepu, 1992; and Sitepu, O'Connor and Li, 1996). Therefore, the March model should not be regarded as a general-purpose PDDF descriptor.This study has examined the validity of the March model using XRPD and neutron powder diffraction (NPD) instruments operated, respectively, by the Curtin Materials Research Group in Perth and by the Australian Nuclear Science and Technology Organisation at the HIFAR reactor facility at Lucas Heights near Sydney. Extensive suites of XRPD and NPD data were measured for uniaxially-pressed powders of molybdite and calcite, for which the compression was systematically varied. It is clear from the various Rietveld refinements that the March model becomes increasingly unsatisfactory as the uniaxial pressure (and, therefore, the level of PO) increases.The March model has been tested with a physical relationship developed by the author which links the March r-parameter to the uniaxial pressure via the powder bulk modulus, B. The agreement between the results obtained from directly measured values of B and from Rietveld analysis with the March model are promising in terms of deducing the powder bulk modulus from the March r-parameter.An additional test of the March model was made with NPD data for specimens mounted, first, parallel to the instrument rotation axis and, then, normal to the axis. The results have provided some further indication that the March model is deficient for the materials considered in the study.During the course of the study, it was found that there are distinct differences between the direction of the near-surface texture in calcite, as measured by XRPD, and bulk texture characterised by NPD. The NPD-derived textures appear to be correct descriptions for the bulk material in uniaxially-pressed powders, whereas the XRPD textures are heavily influenced by the pressing procedure.An additional outcome of the NPD work has been the discovery, made jointly with Dr Brett Hunter of ANSTO, that the popular LHPM Rietveld code did not allow for inclusion of PO contributions from symmetry-equivalent reflections. Revision of the code by Dr Hunter showed that there is substantial bias in Rietveld-March r-parameters if these reflections are not factored correctly into the calculations.Finally, examination of pole-figure data has underlined the extent to which the March model oversimplifies the true distributions. It is concluded that spherical harmonics modelling should be used rather than the March model as a general PO modelling tool.
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Sitepu, Husinsyah. "March-type models for the description of texture in granular materials." Curtin University of Technology, School of Physical Sciences, 1998. http://espace.library.curtin.edu.au:80/R/?func=dbin-jump-full&object_id=10543.
Full textAbstract:
Texture in crystalline materials, i.e. preferred orientation (PO), is of interest in terms of texture-property relationships and also in X-ray diffraction science because PO can cause serious systematic errors in quantitative phase analysis using diffraction data. The single- parameter, pole-density distribution function (PDDF), proposed by March (1932) to represent PO in diffraction analysis, is used widely it Rietveld pattern-fitting following a suggestion by Dollase (1986). While the March model is an excellent descriptor of PO for gibbsite [AI(OH)3] x-ray powder diffraction (XRPD) data (O'Connor, Li and Sitepu, 1991), the model has proved to be deficient for Rietveld modelling with molybdite [Mo03], calcite [CaCO3] and kaolinite [A12O3.2SiO2.2H2O] XRPD data (Sitepu, 1991; O'Connor, Li and Sitepu, 1992; and Sitepu, O'Connor and Li, 1996). Therefore, the March model should not be regarded as a general-purpose PDDF descriptor.This study has examined the validity of the March model using XRPD and neutron powder diffraction (NPD) instruments operated, respectively, by the Curtin Materials Research Group in Perth and by the Australian Nuclear Science and Technology Organisation at the HIFAR reactor facility at Lucas Heights near Sydney. Extensive suites of XRPD and NPD data were measured for uniaxially-pressed powders of molybdite and calcite, for which the compression was systematically varied. It is clear from the various Rietveld refinements that the March model becomes increasingly unsatisfactory as the uniaxial pressure (and, therefore, the level of PO) increases.The March model has been tested with a physical relationship developed by the author which links the March r-parameter to the uniaxial pressure via the powder bulk modulus, B. The agreement between the results obtained from directly measured values of B and from Rietveld analysis with the March model are ++promising in terms of deducing the powder bulk modulus from the March r-parameter.An additional test of the March model was made with NPD data for specimens mounted, first, parallel to the instrument rotation axis and, then, normal to the axis. The results have provided some further indication that the March model is deficient for the materials considered in the study.During the course of the study, it was found that there are distinct differences between the direction of the near-surface texture in calcite, as measured by XRPD, and bulk texture characterised by NPD. The NPD-derived textures appear to be correct descriptions for the bulk material in uniaxially-pressed powders, whereas the XRPD textures are heavily influenced by the pressing procedure.An additional outcome of the NPD work has been the discovery, made jointly with Dr Brett Hunter of ANSTO, that the popular LHPM Rietveld code did not allow for inclusion of PO contributions from symmetry-equivalent reflections. Revision of the code by Dr Hunter showed that there is substantial bias in Rietveld-March r-parameters if these reflections are not factored correctly into the calculations.Finally, examination of pole-figure data has underlined the extent to which the March model oversimplifies the true distributions. It is concluded that spherical harmonics modelling should be used rather than the March model as a general PO modelling tool.
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Giannopoulos, Vassilis. "Efficient VHDL models for various PLD architectures /." Online version of thesis, 1995. http://hdl.handle.net/1850/12238.
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Voukelatos, Dimitrios. "Mathematical description of in-vivo muscle function." Thesis, Loughborough University, 2015. https://dspace.lboro.ac.uk/2134/21772.
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Mathematical relationships have long been used to describe many aspects of muscle function such as the relationship between muscle force and muscle length, muscle force and velocity of contraction or the degree of muscle activation during a contraction. During this work various mathematical expressions have been employed in order to gain an insight into different aspects of muscle activity. The first part of the work examined whether performing a strength protocol on a dynamometer can lead to an increase in eccentric strength output as well as in the neuromuscular activation of the quadriceps group of muscles that appears inhibited during slow concentric and fast eccentric contractions. Neuromuscular activation was modelled via a three-parameter sigmoid function that was also tested for robustness to perturbations in the maximum activation values. During the second part of the study the "functional" hamstrings to quadriceps ratio H:Qfun was expressed as a function of two variables i.e., angular velocity and joint angle. Initially nine-parameter torque-angular velocity-angle profiles were obtained for the knee extensors and flexors from a group of participants. A theoretical 17- parameter H:Qfun function was then derived for each dataset. Subsequently, a simpler, 6-parameter function was derived, RE = aexp(bωn + cθm)-dω1/2θ2 that best reproduced the original 17-parameter fit. Finally, a six-segment subject specific torque-driven model of the Snatch lift was developed in order to investigate the optimal mechanics of the lift. The model simulated the lift from its initiation until the end of the second pull when the feet of the athlete momentarily leave the platform. The six-segment model comprised of foot, shank, thigh, torso (head + trunk), arm and forearm segments with torque generators at the ankle, knee, hip and shoulder joints respectively. The torque profiles were obtained using an isokinetic dynamometer.
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Reddy, Badinehal Asrith. "COMMERCIALIZATION OF A QUANTITATIVE STRUCTURE ACTIVITY RELATIONSHIP TOOL - SARCHITECT." Case Western Reserve University School of Graduate Studies / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=case1295637833.
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Su, Yong. "Mathematical modeling with applications in high-performance coding." Connect to resource, 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1127139848.
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Thesis (Ph. D.)--Ohio State University, 2005.Title from first page of PDF file. Document formatted into pages; contains xiv, 130 p.; also includes graphics (some col.). Includes bibliographical references (p. 125-130). Available online via OhioLINK's ETD Center
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Aherfi, Sarah. "Famille des Marseilleviridae : étude de la pathogénicité potentielle et description du pan-génome." Thesis, Aix-Marseille, 2016. http://www.theses.fr/2016AIXM5024.
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Marseilleviridae est une famille de virus géants isolés initialement à partir de prélèvements environnementaux, dont Marseillevirus est le membre fondateur. La présence des marseillevirus chez l’Homme a été démontrée dans quelques études. Les objectifs sont de mieux documenter la présence des marseillevirus chez l’Homme, de modéliser l’infection par Marseillevirus chez la souris, et enfin, de décrire les génomes des marseillevirus. Nous rapportons un cas d’infection par Marseillevirus chez une patiente atteinte d’un cancer des ganglions, soulevant la question d’un éventuel lien entre Marseillevirus et cancer, à l’instar de l’association existant entre d’autres virus et les cancers. L’infection des souris par Marseillevirus montre que celui-ci persiste un mois au niveau des «amygdales», confirmant le portage pharyngé chronique observé chez un deuxième patient. Enfin, nous identifions deux nouveaux groupes au sein de la famille, soulignant l’importante diversité génétique de la familleMarseilleviridae is a new family of giant viruses primarily isolated from environmental samples and whose Marseillevirus is the founding member. The presence of marseilleviruses in humans has been demonstrated in few studies. The aims are to better document the presence of marseilleviruses in humans, to develop a model of infection of mice with Marseillevirus, and to describe the genomes of marseilleviruses. We report a first caes of infection by Marseillevirus in apatient with a lymph nodes cancer, raising the question of a potential link between Marseillevirus and cancer, as the well established association between some viruses and cancers. The infection of miceshows that Marseillevirus persist one month in the “tonsils”, confirming the chronic pharyngeal carriage reported in a second patient. Finally, we identify two new subgroups in the family, highlighting the considerable genetic diversity of the family
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Arica, Nafiz. "Shape: Representation, Description, Similarity And Recognition." Phd thesis, METU, 2003. http://etd.lib.metu.edu.tr/upload/3/1068873/index.pdf.
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In this thesis, we study the shape analysis problem and propose new methods for shape description, similarity and recognition. Firstly, we introduce a new shape descriptor in a two-step method. In the first step, the 2-D shape information is mapped into a set of 1-D functions. The mapping is based on the beams, which are originated from a boundary point, connecting that point with the rest of the points on the boundary.
At each point, the angle between a pair of beams is taken as a random variable to
define the statistics of the topological structure of the boundary. The third order statistics of all the beam angles is used to construct 1-D Beam Angle Statistics (BAS) functions. In the second step, we apply a set of feature extraction methods on BAS functions in order to describe it in a more compact form. BAS functions eliminate the context-dependency of the representation to the data set. BAS function is invariant to translation, rotation and scale. It is insensitive to distortions. No predefined resolution or threshold is required to define the BAS functions.
Secondly, we adopt three different similarity distance methods defined on the BAS
feature space, namely, Optimal Correspondence of String Subsequences, Dynamic
Warping and Cyclic Sequence Matching algorithms. Main goal in these algorithms is
to minimize the distance between two BAS features by allowing deformations.
Thirdly, we propose a new Hidden Markov Model (HMM)topology for boundary based shape recognition. The proposed topology called Circular HMM is both
ergodic and temporal. Therefore, the states can be revisited in finite time intervals while keeping the sequential information in the string, which represents the shape. It is insensitive to size changes. Since it has no starting and terminating state, it is insensitive to the starting point of the shape boundary.
Experiments are done on the dataset of MPEG 7 Core Experiments Shape-1. It
is observed that BAS descriptor outperforms all the methods in the literature. The
Circular HMM gives higher recognition rates than the classical topologies in shape
analysis applications.
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Dias, Moreira De Souza Fillipe. "Semantic Description of Activities in Videos." Scholar Commons, 2017. http://scholarcommons.usf.edu/etd/6649.
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Description of human activities in videos results not only in detection of actions and objects but also in identification of their active semantic relationships in the scene. Towards this broader goal, we present a combinatorial approach that assumes availability of algorithms for detecting and labeling objects and actions, albeit with some errors. Given these uncertain labels and detected objects, we link them into interpretative structures using domain knowledge encoded with concepts of Grenander’s general pattern theory. Here a semantic video description is built using basic units, termed generators, that represent labels of objects or actions. These generators have multiple out-bonds, each associated with either a type of domain semantics, spatial constraints, temporal constraints or image/video evidence. Generators combine between each other, according to a set of pre-defined combination rules that capture domain semantics, to form larger structures known as configurations, which here will be used to represent video descriptions. Such connected structures of generators are called configurations. This framework offers a powerful representational scheme for its flexibility in spanning a space of interpretative structures (configurations) of varying sizes and structural complexity. We impose a probability distribution on the configuration space, with inferences generated using a Markov Chain Monte Carlo-based simulated annealing algorithm. The primary advantage of the approach is that it handles known computer vision challenges – appearance variability, errors in object label annotation, object clutter, simultaneous events, temporal dependency encoding, etc. – without the need for a exponentially- large (labeled) training data set.
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Saudagar, Abdullah Naseer Ahmed. "Automatic Extraction of Highlights from a Baseball Video Using HMM and MPEG-7 Descriptors." Thesis, University of North Texas, 2011. https://digital.library.unt.edu/ark:/67531/metadc103388/.
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In today’s fast paced world, as the number of stations of television programming offered is increasing rapidly, time accessible to watch them remains same or decreasing. Sports videos are typically lengthy and they appeal to a massive crowd. Though sports video is lengthy, most of the viewer’s desire to watch specific segments of the video which are fascinating, like a home-run in a baseball or goal in soccer i.e., users prefer to watch highlights to save time. When associated to the entire span of the video, these segments form only a minor share. Hence these videos need to be summarized for effective presentation and data management. This thesis explores the ability to extract highlights automatically using MPEG-7 features and hidden Markov model (HMM), so that viewing time can be reduced. Video is first segmented into scene shots, in which the detection of the shot is the fundamental task. After the video is segmented into shots, extraction of key frames allows a suitable representation of the whole shot. Feature extraction is crucial processing step in the classification, video indexing and retrieval system. Frame features such as color, motion, texture, edges are extracted from the key frames. A baseball highlight contains certain types of scene shots and these shots follow a particular transition pattern. The shots are classified as close-up, out-field, base and audience. I first try to identify the type of the shot using low level features extracted from the key frames of each shot. For the identification of the highlight I use the hidden Markov model using the transition pattern of the shots in time domain. Experimental results suggest that with reasonable accuracy highlights can be extracted from the video.
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Sokolov, Andrei P., C. Adam Schlosser, Stephanie Dutkiewicz, Sergey Paltsev, David W. Kicklighter, Henry D. Jacoby, Ronald G. Prinn, et al. "MIT Integrated Global System Model (IGSM) Version 2: Model Description and Baseline Evaluation." MIT Joint Program on the Science and Policy of Global Change, 2005. http://hdl.handle.net/1721.1/29789.
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The MIT Integrated Global System Model (IGSM) is designed for analyzing the global environmental changes that may result from anthropogenic causes, quantifying the uncertainties associated with the projected changes, and assessing the costs and environmental effectiveness of proposed policies to mitigate climate risk. This report documents Version 2 of the IGSM, which like the previous version, includes an economic model for analysis of greenhouse gas and aerosol precursor emissions and mitigation proposals, a coupled atmosphere-ocean-land surface model with interactive chemistry, and models of natural ecosystems. In this global framework the outputs of the combined anthropogenic and natural emissions models provide the driving forces for the coupled atmospheric chemistry and climate models. Climate model outputs then drive a terrestrial model predicting water and energy budgets, CO2, CH4, and N2O fluxes, and soil composition, which feed back to the coupled climate/chemistry model. The first version of the integrated framework (which we will term IGSM1) is described in Prinn et al. (1999) and in publications and Joint Program Reports and Technical Notes provided on the Program’s website (http://mit.edu/globalchange/). Subsequently, upgrades of component model capabilities have been achieved, allowing more comprehensive and realistic studies of global change. Highlights of these improvements include: a substantially improved economics model, needed to provide emissions projections and to assess an increasingly complex policy environment; a new global terrestrial model comprised of state-of-the-art biogeophysical, ecological and natural biogeochemical flux components, which provides an improved capacity to study consequences of hydrologic and ecologic change; the addition of a three-dimensional ocean representation, replacing the previous two-dimensional model, which allows examination of the global thermohaline circulation and its associated climate change impacts; the addition of an explicit oceanic carbon cycle including the impact of the biological pump; the addition of a new urban air pollution model enabling better treatments of human health and climate impacts; and the addition of greater flexibility for study of terrestrial ecosystem and urban pollution effects. This report documents the essential features of the new IGSM structure.Abstract in HTML and technical report in PDF available on the Massachusetts Institute of Technology Joint Program on the Science and Policy of Global Change website (http://mit.edu/globalchange/www/).
This research was supported by the U.S Department of Energy, U.S. Environmental Protection Agency, U.S. National Science Foundation, U.S. National Aeronautics and Space Administration, U.S. National Oceanographic and Atmospheric Administration; and the Industry and Foundation Sponsors of the MIT Joint Program on the Science and Policy of Global Change: Alstom Power (France), American Electric Power (USA), BP p.l.c. (UK/USA), Chevron Corporation (USA), CONCAWE (Belgium), DaimlerChrysler AG (Germany), Duke Energy (USA), J-Power (Japan), Electric Power Research Institute (USA), Electricité de France, ExxonMobil Corporation (USA), Ford Motor Company (USA), General Motors (USA), Murphy Oil Corporation (USA), Oglethorpe Power Corporation (USA), RWE Power (Germany), Shell Petroleum (Netherlands/UK), Southern Company (USA), Statoil ASA (Norway), Tennessee Valley Authority (USA), Tokyo Electric Power Company (Japan), Total (France), G. Unger Vetlesen Foundation (USA).