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Griffier, Romain. "Intégration et utilisation secondaire des données de santé hospitalières hétérogènes : des usages locaux à l'analyse fédérée." Electronic Thesis or Diss., Bordeaux, 2024. http://www.theses.fr/2024BORD0479.
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Les données issues du soin peuvent être utilisées pour des finalités autres que celles pour lesquelles elles ont été collectées initialement : c’est l’utilisation secondaire des données de santé. Dans le contexte hospitalier, afin de lever les verrous de l’utilisation secondaire des données de santé (verrous liés aux données et verrous organisationnels), une stratégie classique consiste à mettre en place un Entrepôt de Données de Santé (EDS). Dans le cadre de cette thèse, trois contributions à l’EDS du CHU de Bordeaux sont décrites. Premièrement, une méthode d’alignement des data éléments de biologie numérique basée sur les instances et conforme aux règles de protection des données à caractère personnel est présentée, avec une F-mesure à 0,850, permettant de réduire l’hétérogénéité sémantique des données. Ensuite, une adaptation du modèle d’intégration des données cliniques d’i2b2 est proposée pour assurer la persistance des données d’un EDS dans une base de données NoSQL, Elasticsearch. Cette implémentation a été évaluée sur la base de données de l’EDS du CHU de Bordeaux et retrouve des performances améliorées en termes de stockage et de temps de requêtage, par rapport à une base de données relationnelle. Enfin, une présentation de l’environnement EDS du CHU de Bordeaux est réalisée, avec la description d’un premier EDS dédié aux usages locaux et qui peut être exploité en autonomie par les utilisateurs finaux (i2b2), et d’un second EDS, dédié aux réseaux fédérés (OMOP) permettant notamment la participation au réseau fédéré DARWIN-EUHealthcare data can be used for purposes other than those for which it was initially collected: this is the secondary use of health data. In the hospital context, to overcome the obstacles to secondary use of healthcaree data (data and organizational barriers), a classic strategy is to set up Clinical Data Warehouses (CDWs). This thesis describes three contributions to the Bordeaux University Hospital’s CDW. Firstly, an instance-based, privacy-preserving, method for mapping numerical biology data elements is presented, with an F-measure of 0,850, making it possible to reduce the semantic heterogeneity of data. Next, an adaptation of the i2b2 clinical data integration model is proposed to enable CDW data persistence in a NoSQL database, Elasticsearch. This implementation has been evaluated on the Bordeaux University Hospital’s CDW, showing improved performance in terms of storage and query time, compared with a relational database. Finally, the Bordeaux University Hospital’s CDW environment is presented, with the description of a first CDW dedicated to local uses that can be used autonomously by end users (i2b2), and a second CDW dedicated to federated networks (OMOP) enabling participation in the DARWIN-EU federated network
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Xiao, Katharine (Katharine J. ). "Towards automatically linking data elements." Thesis, Massachusetts Institute of Technology, 2017. http://hdl.handle.net/1721.1/113450.
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Thesis: M. Eng., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2017.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Cataloged from student-submitted PDF version of thesis.
Includes bibliographical references (pages 91-92).
When presented with a new dataset, human data scientists explore it in order to identify salient properties of the data elements, identify relationships between entities, and write processing software that makes use of those relationships accordingly. While there has been progress made on automatically processing the data to generate features or models, most automation systems rely on receiving a data model that has all the meta information about the data, including salient properties and relationships. In this thesis, we present a first version of our system, called ADEL-Automatic Data Elements Linking. Given a collection of files, this system generates a relational data schema and identifies other salient properties. It detects the type of each data field, which describes not only the programmatic data type but also the context in which the data originated, through a method called Type Detection. For each file, it identifies the field that uniquely describes each row in it, also known as a Primary Key. Then, it discovers relationships between different data entities with Relationship Discovery, and discovers any implicit constraints in the data through Hard Constraint Discovery. We posit two out of these four problems as learning problems. To evaluate our algorithms, we compare the results of each to a set of manual annotations. For Type Detection, we saw a max error of 7%, with an average error of 2.2% across all datasets. For Primary Key Detection, we classified all existing primary keys correctly, and had one false positive across five datasets. For Relationship Discovery, we saw an average error of 5.6%. (Our results are limited by the small number of manual annotations we currently possess.) We then feed the output of our system into existing semi-automated data science software systems - the Deep Feature Synthesis (DFS) algorithm, which generates features for predictive models, and the Synthetic Data Vault (SDV), which generates a hierarchical graphical model. When ADEL's data annotations are fed into DFS, it produces similar or higher predictive accuracy in 3/4 problems, and when they are provided to SDV, it is able to generate synthetic data with no constraint violations.
by Katharine Xiao.
M. Eng.
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Fan, Zhengjie. "Concise Pattern Learning for RDF Data Sets Interlinking." Thesis, Grenoble, 2014. http://www.theses.fr/2014GRENM013/document.
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De nombreux jeux de données sont publiés sur le web à l’aide des technologies du web sémantique. Ces jeux de données contiennent des données qui représentent des liens vers des ressources similaires. Si ces jeux de données sont liés entre eux par des liens construits correctement, les utilisateurs peuvent facilement interroger des données à travers une interface uniforme, comme s’ils interrogeaient un jeu de données unique. Mais, trouver des liens corrects est très difficile car de nombreuses comparaisons doivent être effectuées. Plusieurs solutions ont été proposées pour résoudre ce problème : (1) l’approche la plus directe est de comparer les valeurs d’attributs d’instances pour identifier les liens, mais il est impossible de comparer toutes les paires possibles de valeurs d’attributs. (2) Une autre stratégie courante consiste à comparer les instances selon les attribut correspondants trouvés par l’alignement d’ontologies à base d’instances, qui permet de générer des correspondances d’attributs basés sur des instances. Cependant, il est difficile d’identifier des instances similaires à travers les ensembles de données car,dans certains cas, les valeurs des attributs en correspondance ne sont pas les mêmes.(3) Plusieurs méthodes utilisent la programmation génétique pour construire des modèles d’interconnexion afin de comparer différentes instances, mais elles souffrent de longues durées d’exécution.Dans cette thèse, une méthode d’interconnexion est proposée pour relier les instances similaires dans différents ensembles de données, basée à la fois sur l’apprentissage statistique et sur l’apprentissage symbolique. L’entrée est constituée de deux ensembles de données, des correspondances de classes sur les deux ensembles de données et un échantillon de liens “positif” ou “négatif” résultant d’une évaluation de l’utilisateur. La méthode construit un classifieur qui distingue les bons liens des liens incorrects dans deux ensembles de données RDF en utilisant l’ensemble des liens d’échantillons évalués. Le classifieur est composé de correspondances d’attributs entre les classes correspondantes et de deux ensembles de données,qui aident à comparer les instances et à établir les liens. Le classifieur est appelé motif d’interconnexion dans cette thèse. D’une part, notre méthode découvre des correspondances potentielles entre d’attributs pour chaque correspondance de classe via une méthode d’apprentissage statistique : l’algorithme de regroupement K-medoids,en utilisant des statistiques sur les valeurs des instances. D’autre part, notre solution s’appuie sur un modèle d’interconnexion par une méthode d’apprentissage symbolique: l’espace des versions, basée sur les correspondances d’attributs potentielles découvertes et l’ensemble des liens de l’échantillon évalué. Notre méthode peut résoudre la tâche d’interconnexion quand il n’existe pas de motif d’interconnexion combiné qui couvre tous les liens corrects évalués avec un format concis.L’expérimentation montre que notre méthode d’interconnexion, avec seulement1% des liens totaux dans l’échantillon, atteint une F-mesure élevée (de 0,94 à 0,99)There are many data sets being published on the web with Semantic Web technology. The data sets usually contain analogous data which represent the similar resources in the world. If these data sets are linked together by correctly identifying the similar instances, users can conveniently query data through a uniform interface, as if they are connecting a single database. However, finding correct links is very challenging because web data sources usually have heterogeneous ontologies maintained by different organizations. Many existing solutions have been proposed for this problem. (1) One straight-forward idea is to compare the attribute values of instances for identifying links, yet it is impossible to compare all possible pairs of attribute values. (2) Another common strategy is to compare instances with correspondences found by instance-based ontology matching, which can generate attribute correspondences based on overlapping ranges between two attributes, while it is easy to cause incomparable attribute correspondences or undiscovered comparable attribute correspondences. (3) Many existing solutions leverage Genetic Programming to construct interlinking patterns for comparing instances, however the running times of the interlinking methods are usually long. In this thesis, an interlinking method is proposed to interlink instances for different data sets, based on both statistical learning and symbolic learning. On the one hand, the method discovers potential comparable attribute correspondences of each class correspondence via a K-medoids clustering algorithm with instance value statistics. We adopt K-medoids because of its high working efficiency and high tolerance on irregular data and even incorrect data. The K-medoids classifies attributes of each class into several groups according to their statistical value features. Groups from different classes are mapped when they have similar statistical value features, to determine potential comparable attribute correspondences. The clustering procedure effectively narrows the range of candidate attribute correspondences. On the other hand, our solution also leverages a symbolic learning method, called Version Space. Version Space is an iterative learning model that searches for the interlinking pattern from two directions. Our design can solve the interlinking task that does not have a single compatible conjunctive interlinking pattern that covers all assessed correct links with a concise format. The interlinking solution is evaluated with large-scale real-world data from IM@OAEI and CKAN. Experiments confirm that the solution with only 1% of sample links already reaches a high accuracy (up to 0.94-0.99 on F-measure). The F-measure quickly converges improving on other state-of-the-art approaches, by nearly 10 percent of their F-measure values
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Cherif, Mohamed Abderrazak. "Alignement et fusion de cartes géospatiales multimodales hétérogènes." Electronic Thesis or Diss., Université Côte d'Azur, 2024. http://www.theses.fr/2024COAZ5002.
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L'augmentation des données dans divers domaines présente un besoin essentiel de techniques avancées pour fusionner et interpréter ces informations. Avec une emphase particulière sur la compilation de données géospatiales, cette intégration est cruciale pour débloquer de nouvelles perspectives à partir des données géographiques, améliorant notre capacité à cartographier et analyser les tendances qui s'étendent à travers différents lieux et environnements avec plus d'authenticité et de fiabilité. Les techniques existantes ont progressé dans l'adresse de la fusion des données ; cependant, des défis persistent dans la fusion et l'harmonisation des données de différentes sources, échelles et modalités. Cette recherche présente une enquête complète sur les défis et les solutions dans l'alignement et la fusion des cartes vectorielles, se concentrant sur le développement de méthodes qui améliorent la précision et l'utilisabilité des données géospatiales. Nous avons exploré et développé trois méthodologies distinctes pour l'alignement des cartes vectorielles polygonales : ProximityAlign, qui excelle en précision dans les agencements urbains; l'Alignement Basé sur l'Apprentissage Profond du Flux Optique, remarquable pour son efficacité ; et l'Alignement Basé sur la Géométrie Épipolaire, efficace dans les contextes riches en données. De plus, notre étude s'est penchée sur l'alignement des cartes de géometries linéaires, soulignant l'importance d'un alignement précis et du transfert d'attributs des éléments, pointant vers le développement de bases de données géospatiales plus riches et plus informatives en adaptant l'approche ProximityAlign pour des géometries linéaires telles que les traces de failles et les réseaux routiers. L'aspect fusion de notre recherche a introduit un pipeline sophistiqué pour fusionner des géométries polygonales en se basant sur le partitionnement d'espace, l'optimisation non convexe de la structure de données de graphes et les opérations géométriques pour produire une carte fusionnée fiable qui harmonise les cartes vectorielles en entrée, en maintenant leur intégrité géométrique et topologique. En pratique, le cadre développé a le potentiel d'améliorer la qualité et l'utilisabilité des données géospatiales intégrées, bénéficiant à diverses applications telles que la planification urbaine, la surveillance environnementale et la gestion des catastrophes. Cette étude avance non seulement la compréhension théorique dans le domaine mais fournit également une base solide pour des applications pratiques dans la gestion et l'interprétation de grands ensembles de données géospatialesThe surge in data across diverse fields presents an essential need for advanced techniques to merge and interpret this information. With a special emphasis on compiling geospatial data, this integration is crucial for unlocking new insights from geographic data, enhancing our ability to map and analyze trends that span across different locations and environments with more authenticity and reliability. Existing techniques have made progress in addressing data fusion; however, challenges persist in fusing and harmonizing data from different sources, scales, and modalities.This research presents a comprehensive investigation into the challenges and solutions in vector map alignment and fusion, focusing on developing methods that enhance the precision and usability of geospatial data. We explored and developed three distinct methodologies for polygonal vector map alignment: ProximityAlign, which excels in precision within urban layouts but faces computational challenges; the Optical Flow Deep Learning-Based Alignment, noted for its efficiency and adaptability; and the Epipolar Geometry-Based Alignment, effective in data-rich contexts but sensitive to data quality. Additionally, our study delved into linear feature map alignment, emphasizing the importance of precise alignment and feature attribute transfer, pointing towards the development of richer, more informative geospatial databases by adapting the ProximityAlign approach for linear features like fault traces and road networks. The fusion aspect of our research introduced a sophisticated pipeline to merge polygonal geometries relying on space partitioning, non-convex optimization of graph data structure, and geometrical operations to produce a reliable fused map that harmonizes input vector maps, maintaining their geometric and topological integrity.In practice, the developed framework has the potential to improve the quality and usability of integrated geospatial data, benefiting various applications such as urban planning, environmental monitoring, and disaster management. This study not only advances theoretical understanding in the field but also provides a solid foundation for practical applications in managing and interpreting large-scale geospatial datasets
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Westermark, Vicky. "EVALUATING VIEWS FOR PRODUCING DERIVED DATA ELEMENTS ON TIME SERIES DATA." Thesis, Umeå universitet, Institutionen för datavetenskap, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-175898.
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This paper provides a quantitative comparison of the viability of a set of SQL view implementations on the epidemiological data on the development of the covid-19 virus. It is a naturalistic study of the total execution times of the synthesis of persistent derived information (PDI) from real world time series data. It explores the the trade-offs between view initialization and query execution when choosing between the utilization of virtual, dynamic and material view implementations on such a dataset. To accomplish this, a sqlite3 database is used as a basis for the c-phrase natural language interface, which allows the implementation and use of dynamic views. This study finds that while the mere derivation of rates of change favour a simple dynamic view, rolling n-day averages benefit from materialization. From the results of the experiments, a combination of materialized and dynamic views seem advisable.
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Soheily-Khah, Saeid. "Generalized k-means-based clustering for temporal data under time warp." Thesis, Université Grenoble Alpes (ComUE), 2016. http://www.theses.fr/2016GREAM064/document.
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L’alignement de multiples séries temporelles est un problème important non résolu dans de nombreuses disciplines scientifiques. Les principaux défis pour l’alignement temporel de multiples séries comprennent la détermination et la modélisation des caractéristiques communes et différentielles de classes de séries. Cette thèse est motivée par des travaux récents portant sur l'extension de la DTW pour l’alignement de séries multiples issues d’applications diverses incluant la reconnaissance vocale, l'analyse de données micro-array, la segmentation ou l’analyse de mouvements humain. Ces travaux fondés sur l’extension de la DTW souffrent cependant de plusieurs limites : 1) Ils se limitent au problème de l'alignement par pair de séries 2) Ils impliquent uniformément les descripteurs des séries 3) Les alignements opérés sont globaux. L'objectif de cette thèse est d'explorer de nouvelles approches d’alignement temporel pour la classification non supervisée de séries. Ce travail comprend d'abord le problème de l'extraction de prototypes, puis de l'alignement de séries multiples multidimensionnellesTemporal alignment of multiple time series is an important unresolved problem in many scientific disciplines. Major challenges for an accurate temporal alignment include determining and modeling the common and differential characteristics of classes of time series. This thesis is motivated by recent works in extending Dynamic time warping for aligning multiple time series from several applications including speech recognition, curve matching, micro-array data analysis, temporal segmentation or human motion. However these DTW-based works suffer of several limitations: 1) They address the problem of aligning two time series regardless of the remaining time series, 2) They involve uniformly the features of the multiple time series, 3) The time series are aligned globally by including the whole observations. The aim of this thesis is to explore a generalized dynamic time warping for time series clustering. This work includes first the problem of prototype extraction, then the alignment of multiple and multidimensional time series
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RAPUR, NIHARIKA. "TREATMENT OF DATA WITH MISSING ELEMENTS IN PROCESS MODELLING." University of Cincinnati / OhioLINK, 2003. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1060192778.
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Block, Lorraine Joy. "Mapping nursing wound care data elements to SNOMED-CT." Thesis, University of British Columbia, 2016. http://hdl.handle.net/2429/60290.
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Documentation is a professional responsibility in nursing because it facilitates communication, promotes good nursing care, and acts as a valuable method to demonstrate that legal and agency standards are followed. Nurses are increasingly using health information technologies, such as electronic health records, to document care. To be able to measure and compare the impact of nursing on patient outcomes, standardized clinical terminologies compliant with international standards are necessary. In British Columbia, Canada, nurses use a standardized wound care template to document their assessments and the care they provide to patients; however, the content of this assessment is currently not shared in a computable format between different electronic health records within the province. The purpose of this thesis was to map wound care data elements from the BC Standardized Nursing Wound Documentation standard to SNOMED-CT. To complete this “bottom-up” mapping activity, creation of a conceptual model of knowledge representation for nursing wound care was developed to inform three concurrent methods of mapping (manual, automated, and literature comparison) for 107 data elements. These methods produced candidate lists, which were reviewed by two expert wound care clinicians who created an expert consensus list. Results of this expert consensus list indicated that 40.2% of the terms had direct matches, 1.9% had one-to-many matches, and 57.9% had no matches. The outcome of this study was the creation of a conceptual model of nursing knowledge representation for wound care, a list of mapped wound care data elements to SNOMED-CT, identification of missing and duplicate concepts in SNOMED-CT, and application of concurrent mapping methods to inform the creation of an expert consensus list. The advancement of standardized clinical terminologies to support semantic interoperability between disparate electronic health records is an important measure to ensure patient information is shared throughout the continuum of care. This thesis work provides a method to incorporate local nursing standards into SNOMED-CT, with the intent to ensure that nursing care is represented.Applied Science, Faculty of
Nursing, School of
Graduate
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Speed, Erek R. "Detecting high level story elements from low level data." Thesis, Massachusetts Institute of Technology, 2012. http://hdl.handle.net/1721.1/77019.
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Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2012.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 57-58).
The problem addressed here is yet another artificial intelligence problem that is easily solved by young children yet challenges even sophisticated computer programs. This thesis's canonical example is a scene featuring two entities drinking. In one scene, a cat drinks from a faucet. In the other, a human drinks from a glass. Even young humans can identify that the two images are similar in that they both involve drinking. However, low-level analysis of the scene will find many more differences than similarities in the case cited above. In my research examines ways to detect high-level story elements such as drinking from low-level data such as that which might be produced from analyzing pictures and videos directly. I present a system that accepts as input a collection of high-level events represented in transition space. I analyze, then select the affinity propagation clustering algorithm to group the events using only their low-level representations. To this end, I present a novel algorithm for determining how similar any two points in transition space are. Due to the lack of vision systems capable of providing a varied dataset, I create a system which translates English language descriptions of high-level events and produces a specially formatted transition space file. To support my hypotheses, I presents the results of two experiments using the system described in this thesis. The first experiment uses English language files and the second uses data produced from a set of experimental videos. Using the English language files the system was able to detect groups corresponding to flying and walking among others out of a total set of 16 events.
by Erek R. Speed.
M.Eng.
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Pelan, John Christopher. "The calculation of electron excitation data for iron group elements." Thesis, Queen's University Belfast, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.388173.
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Wiley, David F. "Approximation and visualization of scientific data using higher-order elements /." For electronic version search Digital dissertations database. Restricted to UC campuses. Access is free to UC campus dissertations, 2003. http://uclibs.org/PID/11984.
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Lawlor, Fiona. "Implementation of the metadata elements of the INSPIRE directive." [Denver, Colo.] : Regis University, 2008. http://165.236.235.140/lib/FLawlor2008.pdf.
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Kilingar, Nanda Gopala. "Generation and data-driven upscaling of open foam representational volume elements." Doctoral thesis, Universite Libre de Bruxelles, 2021. https://dipot.ulb.ac.be/dspace/bitstream/2013/313595/4/toc.pdf.
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In this work, a Representative Volume Element (RVE) generator based on the distance fields of arbitrary shaped inclusion packing is used to obtain morphologies of open-foam materials. When the inclusions are spherical, the tessellations of the resultant packing creates morphologies that are similar to physical foam samples in terms of their face-to-pore ratio, edge-to-face ratio and strut length distribution among others. Functions that combine the distance fields can be used to obtain the tessellations along with the necessary variations in the strut geometry and extract these open-foam morphologies. It is also possible to replace the inclusion packing with a predefined set of inclusions that are directly extracted from CT-scan based images.The use of discrete level-set functions results in steep discontinuities in the distance function derivatives. A multiple level-set based approach is presented that can appropriately capture the sharp edges of the open-foam struts from the resultant distance fields. Such an approach can circumvent the discontinuities presented by the distance fields which might lead to spurious stress concentrations in a material behavior analysis.The individual cells are then extracted as inclusion surfaces based on said combinations of the distance functions and their modifications. These surfaces can be joined together to obtain the final geometry of the open-foam morphologies. The physical attributes of the extracted geometries are compared to the experimental data. A statistical comparison is presented outlining the various features. The study is extended to morphologies that have been extracted using CT-scan images. With the help of mesh optimization tools, surface triangulations can be obtained, merged and developed as finite element (FE) models. The models are ready to use in a multi-scale study to obtain the homogenized material behavior. The upscaling can help assess the practical applications of these models by comparing with experimental data of physical samples. The material behavior of the RVEs are also compared with the experimental observations. To increase the computational efficiency of the study, a neural network based surrogate is presented that can replace the micro-scale boundary value problem (BVP) in the multi-scale analysis. The neural networks are built with the help of modules that are specifically designed to predict history dependent behavior and are called Recurrent Neural Networks (RNN). The surrogates are trained to take into account the randomness of the loading that complex material undergo during any given material behavior analysis.Dans ce travail, un générateur de volumes élémentaires représentatifs (VER) basé sur les champs de distance d'un agrégat d'inclusions de forme arbitraire est développé dans le cadre de matériaux moussés à structure ouverte. Lorsque les inclusions sont sphériques, la tessellation de l'agrégat résulte en des morphologies similaires aux échantillons de mousse physique en termes de rapports des nombres de face par pores et de bords par faces, ainsi que de la distribution de la longueur des entretoises, entre autres. Les fonctions qui combinent les champs de distance peuvent être utilisées pour obtenir des tesselations avec les variations nécessaires aux géométries des entretoises et extraire ces morphologies de mousse ouverte. Il est également possible de remplacer l'agrégat d'inclusions par un ensemble prédéfini d'inclusions qui sont directement extraites d'images tomographiques.L'utilisation de fonctions de niveaux discrètes entraîne de fortes discontinuités dans les dérivées des champs de distance. Une approche basée sur des ensembles de niveaux multiples est présentée qui peut capturer de manière appropriée les arêtes vives des entretoises des mousses ouvertes à partir des champs de distance résultants. Une telle approche peut contourner les discontinuités présentées par les champs de distance qui pourraient conduire à des concentrations de contraintes parasites dans une analyse ducomportement des matériaux.Les pores individuels sont ensuite extraits en tant que surfaces d'inclusions sur la base desdites combinaisons des fonctions de distance et de leurs modifications. Ces surfaces peuvent être réunies pour obtenir la géométrie finale des morphologies de mousse ouverte. Les attributs physiques des géométries extraites sont comparés aux données expérimentales. Une comparaison statistique est présentée décrivant les différentes caractéristiques. L'étude est étendue aux morphologies qui ont été extraites à l'aide d'images tomographiques.À l'aide d'outils d'optimisation de maillage, les triangulations des surfaces peuvent être obtenues, fusionnées et développées sous forme de modèles d'éléments finis (FE). Les modèles sont prêts à être utilisés dans une étude multi-échelle pour obtenir le comportement homogénéisé du matériau. La mise à l'échelle peut aider à évaluer les applications pratiques de ces modèles en les comparant aux données expérimentales d'échantillons physiques. Le comportement des matériaux des VERs est également comparé aux observations expérimentales.Pour augmenter l'efficacité de calcul de l'étude, un modèle de substitution basé sur un réseau neuronal est présenté. Ce modèle peut remplacer le problème aux valeurs limites à l'échelle micro dans une analyse multi-échelle. Les réseaux de neurones sont construits à l'aide de modules spécialement conçus pour prédire le comportement dépendant de l'histoire et sont appelés réseaux de neurones récurrents (RNN). Les modèles de substitution sont entrainés pour prendre en compte le caractère aléatoire du chargement que subit un matériau complexe lors d'une analyse de comportement d'un matériau.
Doctorat en Sciences de l'ingénieur et technologie
info:eu-repo/semantics/nonPublished
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Tswane, Siphokazi. "Indigenous knowledge and caregivers' use of data elements in home-based healthcare." Thesis, Cape Peninsula University of Technology, 2012. http://hdl.handle.net/20.500.11838/2302.
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Thesis (MTech (Information Technology))--Cape Peninsula University of Technology, 2012.Home-Based Healthcare (HBHC) is an important aspect of South Africa's healthcare system. HBHC is the provision of care services to patients by trained or semi-trained caregivers at home. In South Africa HBHC was introduced in 2001 to address many problems with traditional healthcare such as overcrowding in public health facilities. South Africa has one of the highest HIV/AIDS infection rates in the world, which is often accompanied by opportunistic infections such as tuberculosis. HBHC is envisaged to address these challenges, thus relieving the burden on primary healthcare. HBHC is itself faced with many problems which include poor information or data management, unclear information flows, and insufficient information storage. It is also not clear how caregivers use data elements and there is no coherent indigenous knowledge base for the capturing, implementation and utilisation of data elements in local HBHC providers. This is particularly important to caregivers who rely on frameworks of indigenous knowledge in interpreting and making decisions on how to provide a care service to patients. In reality, caregivers operate in indigenous environments requiring the utilisation of local knowledge. This study explores the relationships between, and approaches to, data elements in different HBHC providers and communities. Three interpretive case studies in the Eastern and Western Cape Provinces of South Africa were conducted. Semistructured interviews, focus groups, participant observation and document analysis were used for data collection. The primary research question was: What happens when caregivers from various communities interact with data elements when providing a care service? Caregivers' indigenous knowledge and use of data elements was then harnessed in a knowledge base. The results from this study can be used by HBHC managers to develop their forms and training materials as the initial set of data elements used in HBHC has been identified. Caregivers from different communities can also learn how these data elements are used in other communities.
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Rai, Dovan. "Math Learning Environment with Game-Like Elements and Causal Modeling of User Data." Digital WPI, 2011. https://digitalcommons.wpi.edu/etd-theses/722.
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Educational games intend to make learning more enjoyable, but at the potential cost of compromising learning efficiency. Therefore, instead of creating educational games, we create learning environment with game-like elements: the elements of games that are engaging. Our approach is to assess each game-like element in terms of benefits such as enhancing engagement as well as its costs such as sensory or working memory overload, with a goal of maximizing both engagement and learning. We developed different four versions of a math tutor with different degree of being game-like such as adding narrative and visual feedback. Based on a study with 297 students, we found that students reported more satisfaction with more 'game-like' tutor but we were not able to detect any conclusive difference in learning among the different tutors. We collected student data of various types such as their attitude and enjoyment via surveys, performance within tutor via logging, and learning as measured by a pre/post-test. We created a causal model using software TETRAD and contrast the causal modeling approach to the results we achieve with traditional approaches such as correlation matrix and multiple regression. Relative to traditional approaches, we found that causal modeling did a better job at detecting and representing spurious association, and direct and indirect effects within variables. Causal model, augmented with domain knowledge about likely causal relationships, resulted in much more plausible and interpretable model. We propose a framework for blending exploratory results from causal modeling with randomized controlled studies to validate hypotheses.
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Dadson, Daniel K. "Impact of Environmental Classification on Steel Girder Bridge Elements Using Bridge Inspection Data." Diss., Virginia Tech, 2001. http://hdl.handle.net/10919/27772.
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State Departments of Transportation (DOT's) have established Bridge Management Systems (BMS) with procedures to aid in estimating service lives of bridge components and elements. Service life estimates, together with cost information, are used to develop life-cycle costs of bridges. These estimates are necessary to prioritize and optimize bridge improvement programs within budgetary constraints. Several factors, including age, traffic, and environment have been identified in current BMS literature as being directly responsible for the deterioration of bridge components or elements. However, no formal methodology exists to determine the effects of the environment. Estimating bridge elements service lives, without considering the effect of environmental factors, could potentially lead to biased estimates. A methodology is proposed using statistical analysis to determine the effects of environmental regions on service life estimates of steel girder bridge component (concrete deck) and element/protective system (girder paint) using bridge inspection field data collected by bridge inspectors. Further, existing deterioration models are incapable of using the non-numeric element level inspection data, which most state DOT's have been collecting for nearly thirty years per Federal Highway Administration guidelines. The data format used were the numerical condition appraisal scale (9 through 0) for concrete deck component, and the letter condition appraisal (G-F-P-C) for steel girder paint element. The methodology proposed an environmental classification system for use in BMS programs. In addition, least squares mean and corresponding standard errors and also means and corresponding standard deviations of service lives at the component and element/protective system levels were estimated. The steel girder paint estimated service lives can be used in scheduling maintenance, repair and rehabilitation operations, and also in life-cycle costs analysis at the project and network levels. Because of limitations in the concrete deck data sets, the estimated concrete deck service lives are not true estimates of their service lives but do reflect the influence of environmental exposure characteristics on their performance.Ph. D.
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Jin, Ruxiang. "Nonlinear etalons and nonlinear waveguides as decision-making elements in photonic switching." Diss., The University of Arizona, 1989. http://hdl.handle.net/10150/184807.
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This dissertation describes our recent results in the study of various types of photonic switches. Special attention is given to the devices with Fabry-Perot etalon or planar waveguide structures based on dispersive optical nonlinearities. Basic optical logic functions, such as digital pattern recognition, symbolic substitution, and all-optical compare-and-exchange operation are demonstrated using ZnS and ZnSe nonlinear interference filters. Differential gain, cascading, and optical latching circuits are demonstrated using GaAs/AlGaAs multiple-quantum-well nonlinear etalons that are compatible with diode-laser sources, and the relationship between differential gain and device response time is established through a thorough investigation of the switching dynamics. Preliminary results also indicate that optical fibers can be used as interconnects between optical logic gates. Picosecond all-optical switching with good (> 3:1) contrast is demonstrated for the first time in single-mode strip-loaded GaAs/AlGaAs nonlinear directional couplers (NLDC's). The anisotropy of quantum-well structure to light polarization is used to achieve polarization-dependent two-beam switching, and the optical Stark effect is used to demonstrate all-optical modulation in an NLDC with subpicosecond recovery time.
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Badenga, Rahul. "Path planning of mobile elements in time constrained data gathering for wireless sensor networks." Thesis, California State University, Long Beach, 2016. http://pqdtopen.proquest.com/#viewpdf?dispub=10105262.
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The problem of data gathering is considered in a wireless sensor network using mobile elements. In particular, we consider a case where data is produced at a particular node and it needs to be delivered to a predefined sink in a given time interval. Mobile elements in a wireless sensor network travel in a predefined path; they collect the data from the nodes and they deliver it to the sink. Each and every node must be visited by the mobile element, which must reach the sink within a given time constraint. Therefore, the goal is to plan a path for the mobile element that minimizes the total length travelled. We propose an algorithmic solution that builds node-disjoint tours that always include the sink, that cover the network and also optimize the total length travelled. We provide an Integer Linear Programming Algorithm (LPF) for the problem and propose two heuristic approaches for building the tours. We also evaluate the performance of our algorithm by comparing it to our optimal solution, also working on few alternative heuristic, commonly used in time-window vehicle routing problems, and demonstrating the superiority of our solution.
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Yan, Yujin. "Μοbile data analysis : rοbust alignment and flexible clustering methοds." Electronic Thesis or Diss., Normandie, 2024. http://www.theses.fr/2024NORMIR14.
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La popularité des appareils mobiles dans la vie moderne a révolutionné la communication, la navigation et les activités quotidiennes. Les appareils mobiles génèrent une grande quantité de données, y compris un large éventail de comportements des utilisateurs, allant du suivi de la localisation aux modèles de communication et aux données des capteurs. Ces données à multiples facettes ne saisissent pas seulement les interactions entre les individus et leurs appareils, mais révèlent également les tendances et les préférences sociales. Reconnaissant l'importance des données mobiles, nos recherches sont consacrées à l'exploration et à l'exploitation des comportements quotidiens des utilisateurs enregistrés par les appareils mobiles. Dans un premier temps, nous nous concentrons sur l'analyse des données de trajectoire, un composant des données mobiles qui est généralement représenté sous la forme d'une séquence spatio-temporelle. En utilisant les informations sémantiques intégrées dans les points de trajectoire, nous pouvons obtenir des informations sur les comportements et les activités des utilisateurs. Cependant, l'intégration des dimensions spatiales et temporelles augmente la complexité de l'analyse. Nous proposons une architecture de regroupement de trajectoires basée sur la sémantique pour analyser les données de trajectoires, qui comprend le prétraitement des données, l'exploration de la similarité et les méthodes de regroupement. En outre, nous introduisons un modèle d'exploration des similitudes fondé sur la programmation dynamique pour quantifier la similitude entre les trajectoires, améliorant ainsi notre compréhension des données mobiles. Une analyse expérimentale complète est menée sur un ensemble de données réelles afin de comparer notre modèle avec des méthodes de référence. Les résultats de la comparaison montrent la capacité de notre algorithme à examiner efficacement les associations au sein des données de trajectoire. Pour améliorer le contrôle expérimental, nous proposons un modèle de génération de données simulant des scénarios de la vie quotidienne en générant des données aléatoires fondées sur des données d'utilisateurs réels. Grâce à des comparaisons quantitatives entre l'architecture proposée et d'autres approches, notre algorithme démontre des performances acceptables. En passant des données de trajectoire aux données mobiles multivariées, nous sommes confrontés au défi d'utiliser efficacement divers types de capteurs pour extraire des informations subtiles sur le comportement de l'utilisateur. En introduisant l'algorithme d'alignement de séquences multivariées unidimensionnelles (1D MSA) et l'algorithme d'alignement de séquences multivariées bidimensionnelles (2D MSA), nous facilitons une analyse complète des données mobiles multivariées. Alors que l'algorithme 1D MSA privilégie l'efficacité de calcul, l'algorithme 2D MSA 2D excelle dans l'extraction de similitudes subtiles entre les séquences, ce qui permet une analyse plus détaillée. Parallèlement, nous utilisons différentes méthodes de regroupement pour analyser les sous-séquences similaires obtenues par les deux algorithmes et nous avons obtenu des résultats de regroupement similaires, voire identiques. En outre, les états de l'utilisateur représentés par chaque catégorie dans les résultats du regroupement sont très faciles à interpréter. Cela indique que nos algorithmes peuvent obtenir des résultats stables et cohérents sur des problèmes réels. En outre, nous comparons les sous-séquences similaires obtenues par l'algorithme 2D MSA et les méthodes de référence. Les résultats montrent que l'algorithme 2D MSA que nous proposons est plus performant lorsqu'il s'agit de capturer des similarités subtiles à partir des données. Cette performance robuste fait de l'algorithme 2D MSA un outil puissant pour extraire des sous-séquences significatives dans des données mobiles multivariées, contribuant ainsi à une meilleure interprétation des données et [...]The widespread popularity of mobile devices in modern life has brought a revolution in communication, navigation, and daily activities. Mobile devices generate a vast amount of data, including a wide range of user behaviors from location tracking to communication patterns and sensor data. This multifaceted data not only captures the interactions between individuals and their devices, but also reveals social trends and preferences. Recognizing the importance of mobile data, our research is dedicated to exploring and mining the user daily behavior recorded by mobile devices. Initially, we focus on analyzing trajectory data, which is a component of mobile data that is typically represented as a spatio-temporal sequence. Using the semantic information embedded in trajectory points, we can gain insights into users' behaviors and activities. However, the integration of spatial and temporal dimensions increases the complexity of the analysis. We propose a semantic-based trajectory clustering (STC) architecture to analyze trajectory data, which includes data preprocessing, similarity exploration, and clustering methods. In addition, we introduce a dynamic programming-based similarity exploration (DPD) model to quantify the similarity between trajectories, thus enhancing our understanding of mobile data. A comprehensive experimental analysis is conducted on a real-world dataset to compare the DPD model with the other baseline methods. The comparison results show the adeptness of our DPD algorithm in effectively examining associations within trajectory data. To enhance experimental control, we propose a data generation model simulating daily life scenarios by generating random data based on real user data. Through quantitative comparisons between the proposed STC architecture and other approaches, our algorithm demonstrates good performance. Transitioning from trajectory data to multivariate mobile data, we are challenged to effectively utilize various sensor types to extract subtle insights into user behavior. By introducing one-dimensional multivariate sequence alignment (1D MSA) algorithm and two-dimensional multivariate sequence alignment (2D MSA) algorithm, we facilitate a comprehensive analysis of multivariate mobile data. While the 1D MSA algorithm prioritizes computational efficiency, the 2D MSA algorithm excels at extracting subtle similarities between sequences, providing a more detailed analysis. Meanwhile, we use some different clustering methods to analyze the similar subsequences obtained by the two algorithms and obtained similar or even identical clustering results. Moreover, the user states represented by each category in the clustering results are highly interpretable. This indicates that our algorithms can obtain stable and real-life consistent results. Furthermore, we compare the similar subsequences obtained by 2D MSA algorithm and baseline methods. The results show that our proposed 2D MSA algorithm has superior performance in capturing subtle similarity from the data. This robust performance makes the 2D MSA algorithm as a powerful tool for extracting meaningful subsequences in multivariate mobile data, contributing to enhanced data interpretation and practical applications
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Fu, Wai, and 符慧. "In silico prediction of cis-regulatory elements of genes involved in hypoxic-ischaemic insult." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2006. http://hub.hku.hk/bib/B36986896.
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Moritz, Rick Patrick Constantin. "Routine activity extraction from local alignments in mobile phone context data." Thesis, Rouen, INSA, 2014. http://www.theses.fr/2014ISAM0001/document.
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L'homme, de manière générale apprécie ses habitudes. Nous proposons une méthodologie d'identification des activités de routine depuis des régularités extraites des données de contexte, acquises sur téléphone portable. Notre choix algorithmique se base sur l'algorithme d'alignement proposé par Lecroq et al. L'algorithme cherche à aligner des séquences de n-uplets de données du contexte. Les séquences algorithmiques correspondent aux traces d'utilisation régulières. Notre contribution technique consiste à l'amélioration de l'algorithme afin qu'il puisse exploiter la nature séquentielle des données se basant sur une approche d'optimisation locale. Les deux apports rendent la solution adaptée aux données dont la volumétrie compatibles avec les données de contexte.Afin d'évaluer notre approche, nous présentons un générateur de données simulées et une campagne d'acquisition de données réelles. Ces données sont utilisées pour valider notre approcheHumans are creatures of habit, often developing a routine for their day-to-day life. We propose a way to identify routine as regularities extracted from the context data of mobile phones. We choose Lecroq et al.'s existing state of the art algorithm as basis for a set of modifications that render it suitable for the task. Our approach searches alignments in sequences of n-tuples of context data, which correspond to the user traces of routine activity. Our key enhancements to this algorithm are exploiting the sequential nature of the data an early maximisation approach. We develop a generator of context-like data to allow us to evaluate our approach. Additionally, we collect and manually annotate a mobile phone context dataset to facilitate the evaluation of our algorithm. The results allow us to validate the concept of our approach
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Neves, Vasco de Matos Ferreira Mendes. "Abundances of elements in exoplanet host stars." Master's thesis, Universidade de Aveiro, 2008. http://hdl.handle.net/10773/15237.
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Mestrado em FísicaIn this work we present an uniform study of the chemical abundances of 12 elements (Si, Ca, Sc, Ti, V, Cr, Mn, Co, Ni, Na, Mg and Al) derived from the spectra of 451 stars of one of the HARPS GTO planet search programs, which has 66 planet bearing stars. The main goal of this study is the investigation of the possible differences between the abundances of the stars with and without planets. We have confirmed that there is an overabundance of metallicity in planet host stars, common to all species, as expected. We have also found that there is no difference in the galactic chemical evolution trends between stars with and without planets, as observed in the [X/Fe] vs. [Fe/H] plots. The stars that harbour planetary companions simply seem to be in the high metallicity tail of the distribution. We have only found one case of clear overabundance for a fixed [Fe/H] (HD147513) where the pollution scenario might be important. This particular star needs to be investigated in a future work. We also need to explore the possibility of the existence of a different population of stars with high [X/Fe] ratios in the region of [Fe/H] < 0 that was detected in the plots of [X/Fe] vs [Fe/H].
Neste trabalho apresentamos um estudo uniforme de abundâncias químicas de 12 elementos (Si, Ca, Sc, Ti, V, Cr, Mn, Co, Ni, Na, Mg e Al) a partir dos espectros de 451 estrelas de um dos programas HARPS GTO de procura de exoplanetas. Destas estrelas, 66 têm planetas confirmados. O objectivo principal deste trabalho é a investigação das possíveis diferenças entre as abundâncias químicas de estrelas com e sem planetas. Confirmámos que existe uma maior abundância química de todos os elementos nas estrelas com planetas, como era esperado. Constatámos também, através da análise dos gráficos de [X/Fe] vs. [Fe/H], que não existem diferenças nas tendências da evolução química da galáxia entre estrelas com e sem planetas. As estrelas que têm planetas parecem estar apenas no extremo de maior metalicidade da distribuição. Encontrámos apenas um caso em que se verifica uma maior abundância de alguns elementos para um [Fe/H] fixo (HD147513), onde o cenário de enriquecimento químico por poluição poderá ser importante. Este caso em particular precisa de ser investigado num trabalho futuro. É necessário também explorar a possível existência de uma população diferente de estrelas com maior metalicidade na região de [Fe/H] < 0 detectada nos gráficos de [X/Fe] vs. [Fe/H].
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Savage, Ian Francis. "The development of the methodology for the analysis of trace elements in clinical samples using TXRF." Thesis, University of Hull, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.301637.
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Muto, Shunsuke, and Yusuke Sasano. "Energy-drift correction of electron energy-loss spectra from prolonged data accumulation of low SNR signals." Oxford University Press, 2008. http://hdl.handle.net/2237/20779.
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Li, Cong. "A comparably robust approach to estimate the left-censored data of trace elements in Swedish groundwater." Thesis, Uppsala universitet, Statistiska institutionen, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-175833.
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Groundwater data in this thesis, which is taken from the database of Sveriges Geologiska Undersökning, characterizes chemical and quantitative status of groundwater in Sweden. The data usually is recorded with only quantification limits when it is below certain values. Accordingly, this thesis is aiming at handling such kind of data. The thesis considers this topic by using the EM algorithm to get the results from maximum likelihood estimation. Consequently, estimations of distributions on censored data of trace elements are expounded on. Related simulations show that the estimation is acceptable.
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Schwieger, Felix. "Orbit Determination for UWE-4 based on Magnetometer and Sun Sensor Data using Equinoctial Orbital Elements." Thesis, Luleå tekniska universitet, Institutionen för system- och rymdteknik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-61551.
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An autonomous, real-time orbit determination system was developed within thiswork for the next iteration of the University of W¨urzburg’s CubeSat programme.The algorithm only made use of magnetometer and sun sensors, which already wereimplemented on UWE-3, the third satellite in the programme. Previous developedsystems used the same approach, however the unique aspect in this work is thatthe algorithm was implemented using equinoctial elements.A Runge-Kutta-4 integrator propagated the orbit position using the orbit dynamicsunder the consideration of J2-perturbations. Afterwards, an Extended KalmanFilter corrected the position through processing the two measurements.The algorithm was then tested under multiple conditions. At first, a two weekstability test was conducted using simulated data, followed by a test with recordedsatellite data. These have shown a mean error of 13.2 km and 12.6 km respectively.Lastly, the algorithm was translated in to C and evaluated on a micro-controller.
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Pati, Amrita. "Modeling and Analysis of Regulatory Elements in Arabidopsis thaliana from Annotated Genomes and Gene Expression Data." Thesis, Virginia Tech, 2005. http://hdl.handle.net/10919/44132.
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Modeling of cis-elements in the upstream regions of genes is a challenging computational problem. A set of regulatory motifs present in the promoters of a set of genes can be modeled by a biclique. Combinations of cis-elements play a vital role in ascertaining that the correct co-action of transcription factors binding to the gene promoter, results in appropriate gene expression in response to various stimuli. Geometrical and spatial constraints in transcription factor binding also impose restrictions on order and separation of cis-elements. Not all regulatory elements that coexist are biologically significant. If the set of genes in which a set of regulatory elements co-occur, are tightly correlated with respect to gene expression data over a set of treatments, the regulatory element combination can be biologically directed.
The system developed in this work, XcisClique, consists of a comprehensive infrastructure for annotated genome and gene expression data for Arabidopsis thaliana. XcisClique models cis-regulatory elements as regular expressions and detects maximal bicliques of genes and motifs, called itemsets. An itemset consists of a set of genes (called a geneset) and a set of motifs (called a motifset) such that every motif in the motifset occurs in the promoter of every gene in the geneset. XcisClique differs from existing tools of the same kind in that, it offers a common platform for the integration of sequence and gene expression data. Itemsets identified by XcisClique are not only evaluated for statistical over-representation in sequence data, but are also examined with respect to the expression patterns of the corresponding geneset. Thus, the results produced are biologically directed. XcisClique is also the only tool of its kind for Arabidopsis thaliana, and can also be used for other organisms in the presence of appropriate sequence, expression, and regulatory element data. The web-interface to a subset of functionalities, source code and supplemental material are available online at http://bioinformatics.cs.vt.edu/xcisclique.Master of Science
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Nelson, Michael Graham. "Bioinformatic approaches to detect transposable element insertions in high throughput sequence data from Saccharomyces and Drosophila." Thesis, University of Manchester, 2016. https://www.research.manchester.ac.uk/portal/en/theses/bioinformatic-approaches-to-detect-transposable-element-insertions-in-high-throughput-sequence-data-from-saccharomyces-and-drosophila(df6427f7-2f8e-4de5-81eb-51f6bfab514a).html.
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Transposable elements (TEs) are mutagenic mobile DNA sequences whose excision and insertion are powerful drivers of evolution. Some TE families are known to target specific genome features, and studying their insertion preferences can provide information about both TE biology and the state of the genome at these locations. To investigate this, collecting large numbers of insertion sites for TEs in natural populations is required. Genome resequencing data can potentially provide a rich source of such insertion sites. The field of detecting these "non-reference" TE insertions is an active area of research, with many methods being released and no comprehensive review performed. To drive forward knowledge of TE biology and the field of non-reference TE detection, we created McClintock, an integrated pipeline of six TE detection methods. McClintock lowers the barriers against use of these methods by automating the creation of the diverse range of input files required whilst also setting up all methods to run simultaneously and standardising the output. To test McClintock and its component methods, it was run on both simulated and real Saccharomyces cerevisiae data. Tests on simulated data reveal the general properties of component methods' predictions as well as the limitations of simulated data for testing software systems. Overlap between results from the McClintock component methods show many insertions detected by only one method, highlighting the need to run multiple TE detection methods to fully understand a resequenced sample. Utilising the well characterised properties of S. cerevisiae TE insertion preferences, real yeast population resequencing data can act as a biological validation for the predictions of McClintock. All component methods recreated previously known biological properties of S. cerevisiae TE insertions in natural population data. To demonstrate the versatility of McClintock, we applied the system to Drosophila melanogaster resequencing data. 27 Schneider's cell lines were sequenced and analysed with McClintock. In addition to demonstrating the scalability of McClintock to larger genomes with more TE families, this exposed ongoing transposition in S2 cell lines. Likewise, the use of non-reference TE insertions as variable sites allowed us to recreate the relationships between S2 sub-lines, confirming that S1, S2, and S3 were most likely established separately. The results also suggest that there are several S2 sub-lines in use and that these sub-lines can differ from each other in TE content by hundreds of non-reference TE copies. Overall this thesis demonstrates that the McClintock pipeline can highlight problems in TE detection from genome data as well as revealing that much can still be learned from this data source.
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Yancoskie, Michelle N. [Verfasser], and Frank [Akademischer Betreuer] Chan. "Identifying and characterizing transcriptional regulatory elements from chromosome conformation capture data / Michelle N. Yancoskie ; Betreuer: Frank Chan." Tübingen : Universitätsbibliothek Tübingen, 2019. http://d-nb.info/1200916484/34.
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Dennis, Tristan Philip Wesley. "Mining genome data for endogenous viral elements and interferon stimulated genes : insights into host virus co-evolution." Thesis, University of Glasgow, 2018. http://theses.gla.ac.uk/30887/.
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Paleovirology is the study of viruses over evolutionary timescales. Contemporary paleovirological analyses often rely on sequence data, derived from organism genome assemblies. These sequences are the germline inherited remnants of past viral infection, in the form of endogenous viral elements and the host immune genes that are evolving to combat viruses. Their study has found that viruses have exerted profound influences on host evolution, and highlighted the conflicts between viruses and host immunity. As genome sequencing technology cheapens, the accumulation of genome data increases, furthering the potential for paleovirological insights. However, data on ERVs, EVEs and antiviral gene evolution, are often not captured by automated annotation pipelines. As such, there is scope for investigations and tools that investigate the burgeoning bulk of genome data for virus and and antiviral gene sequence data in the search of paleovirological insight.
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Дядечко, Алла Миколаївна, Алла Николаевна Дядечко, Alla Mykolaivna Diadechko, and A. Dmitriyev. "250 dvds on a quarter: new method of self-assembljng nanoscale elements could transform data storage industry." Thesis, Вид-во СумДУ, 2009. http://essuir.sumdu.edu.ua/handle/123456789/16939.
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Golinski, Anne. "Automating Network System Configurations for Vendor-Specific Network Elements." Thesis, KTH, Skolan för informations- och kommunikationsteknik (ICT), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-211678.
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In present day, telecommunications stakeholders have not yet fully automated hardware configurations. Network configuration and reconfiguration is a repetitive, time consuming, and error prone process. To address this problem this bachelor thesis is going to shed light on the benefits of an automated configuration and topology verification process. To this end, a proof of concept system, Enna, has been developed in a case study together with an ISP stakeholder. Enna reads the current network state, applies predetermined configurations loaded from text-files, and automatically verifies the network state. The goals of this thesis are as follows: development of Enna to illustrate the simplicity in the implementation, compare the automated network reconfiguration to a fully manual one, and finally discuss potential benefits or problems in switching to an automated network configuration. Since this thesis is carried out in collaboration with an ISP working with Cisco IOS XR devices, Enna is only tested for basic network protocols common in such environment, the conclusions drawn in this paper are therefore only applicable to such context.I dagens läge tillämpar inte telekommunikationsintressenter automatiserade processer som standard. Nätverkskonfigurering och omkonfigurering är en repetitiv, tidskrävande och felbenägen process. För att adressera detta problem kommer denna kandidatavhandling belysa fördelarna med en automatisk nätverkskonfiguration och verifieringsprocess. För detta ändamål har ett system, Enna, framtagits som ett bevis på konceptets ändamålsenlighet. Enna läser aktuell nätverksstatus, tillämpar förutbestämda konfigurationer som laddas in från textfiler, och verifierar nätverkstatus automatiskt. Målet för detta examensarbete lyder: utveckling av Enna för att illustreara simplisteten i framtagandet, jämföra en automatisk nätverkskonfiguration med en manuell , och slutligen diskutera fördelar och problem vid byte till en automatiserad närverskonfiguration. Eftersom att detta examensarbete genomförts i samarbete med en ISP som arbetar med Cisco IOS XR-enheter, och Enna endast testats med grundläggande närverksprotokoll vanliga för dessa miljöer, kommer slutsatserna i detta dokument endast vara tillämpbara i dylikt sammanhang.
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Finch, Dezon K. "TagLine: Information Extraction for Semi-Structured Text Elements In Medical Progress Notes." Scholar Commons, 2012. http://scholarcommons.usf.edu/etd/4321.
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Text analysis has become an important research activity in the Department of Veterans Affairs (VA). Statistical text mining and natural language processing have been shown to be very effective for extracting useful information from medical documents. However, neither of these techniques is effective at extracting the information stored in semi-structure text elements. A prototype system (TagLine) was developed as a method for extracting information from the semi-structured portions of text using machine learning. Features for the learning machine were suggested by prior work, as well as by examining the text, and selecting those attributes that help distinguish the various classes of text lines. The classes were derived empirically from the text and guided by an ontology developed by the Consortium for Health Informatics Research (CHIR), a nationwide research initiative focused on medical informatics. Decision trees and Levenshtein approximate string matching techniques were tested and compared on 5,055 unseen lines of text. The performance of the decision tree method was found to be superior to the fuzzy string match method on this task. Decision trees achieved an overall accuracy of 98.5 percent, while the string match method only achieved an accuracy of 87 percent. Overall, the results for line classification were very encouraging. The labels applied to the lines were used to evaluate TagLines' performance for identifying the semi-structures text elements, including tables, slots and fillers. Results for slots and fillers were impressive while the results for tables were also acceptable.
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Gassama, Edrissa. "PIEZOELECTRIC INVERSE PROBLEMS WITH RESONANCE DATA: A SEQUENTIAL MONTE CARLO ANALYSIS." Case Western Reserve University School of Graduate Studies / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=case1396623563.
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Heldreich, Georgina. "A quantitative analysis of the fluvio-deltaic Mungaroo Formation : better-defining architectural elements from 3D seismic and well data." Thesis, University of Manchester, 2017. https://www.research.manchester.ac.uk/portal/en/theses/a-quantitative-analysis-of-the-fluviodeltaic-mungaroo-formation-betterdefining-architectural-elements-from-3d-seismic-and-well-data(866e245b-ba19-455d-924c-6d20af3dd700).html.
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Upper to lower delta plain fluvial sand bodies, sealed by delta plain mudstones, form important hydrocarbon reservoir targets. Modelling complex geobodies in the subsurface is challenging, with a significant degree of uncertainty on dimensions, distribution and connectivity. Studies of modern and ancient paralic systems have produced a myriad of nomenclature and hierarchy schemes for classifying fluvial architectural elements; often lacking clearly-defined terminology. These are largely based on outcrop data where lateral and vertical relationships of bounding scour surfaces can be assessed in detail. Many of these key defining criteria are difficult to recognise or cannot be obtained from typical 3D seismic reflection data at reservoir depths greater than or equal to 2 km subsurface. This research provides a detailed statistical analysis of the Triassic fluvio-deltaic Mungaroo Formation on the North West Shelf of Australia, which is one of the most important gas plays in the world. A multidisciplinary approach addresses the challenge of characterising the reservoir by utilising an integrated dataset of 830 m of conventional core, wireline logs from 21 wells (penetrating up to 1.4 km of the upper Mungaroo Fm) and a 3D seismic volume covering approximately 10,000 km2. Using seismic attribute analysis and frequency decomposition, constrained by well and core data, the planform geobody geometries and dimensions of a variety of architectural elements at different scales of observation are extracted. The results produce a statistically significant geobody database comprising over 27,000 measurements made from more than 6,000 sample points. Three classes of geobodies are identified and interpreted to represent fluvial channel belts and channel belt complexes of varying scales. Fluvial geobody dimensions and geomorphology vary spatially and temporally and the inferred controls on reservoir distribution and architecture are discussed. Results document periods of regression and transgression, interpreted in relation to potential allocyclic and autocyclic controls on the evolution of the depositional system. Statistical analysis of width-to-thickness dimensions and key metrics, such as sinuosity, provided a well-constrained and valuable dataset that augments, and has been compared to, existing published datasets. Uncertainty in interpretation caused by data resolution is addressed; something recognised in many other studies of paralic systems. Given the data distribution, type and resolution, geobodies have possible interpretations as either incised valleys or amalgamated channel belts, with implications for developing predictive models of the system. This study offers the first published, statistically significant dataset for the Mungaroo Formation. It builds upon previous regional work, offering a detailed analysis of this continental scale paralic system and provides insight into the controls and mechanisms that influenced its spatial and temporal evolution. Focusing on improved understanding of geobody distribution and origin, the statistical parameters generated provide a robust dataset that can be used for 3D static reservoir models of analogue systems. Thus, helping to constrain potential geobody dimensions and reduce the uncertainties associated with modelling.
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Sampath, Rahul Srinivasan. "A parallel geometric multigrid method for finite elements on octree meshes applied to elastic image registration." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2009. http://hdl.handle.net/1853/29702.
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Thesis (Ph.D)--Computing, Georgia Institute of Technology, 2009.Committee Chair: Vuduc, Richard; Committee Member: Biros, George; Committee Member: Davatzikos, Christos; Committee Member: Tannenbaum, Allen; Committee Member: Zhou, Hao Min. Part of the SMARTech Electronic Thesis and Dissertation Collection.
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Bacheller, John S. "Design and implementation of a prototype microcomputer database management system for the standardization of data elements for the Department of Defense." Thesis, Monterey, California : Naval Postgraduate School, 1990. http://handle.dtic.mil/100.2/ADA238888.
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Thesis (M.S. in Information Systems)--Naval Postgraduate School, September 1990.Thesis Advisor(s): Dolk, Daniel R. Second Reader:Kamel, Magdi N. "September 1990." Description based on title screen viewed on December 16, 2009. DTIC Descriptor(s): Fields(computer programs), management information systems, standardization, department of defense, systems engineering, data management, theses, prototypes, sharing, microcomputers, hierarchies, viewers, requirements, dictionaries, data bases, functions. Author(s) subject terms: Data management standardization, data element dictionary, data element standardization, object oriented, logical design, application design. Includes bibliographical references (p. 237). Also available in print.
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Usu, Kerem. "Identification Of Soft Tissue Mechanical Material Model And Corresponding Parameters From In Vivo Experimental Data By Using Inverse Finite Element Method." Master's thesis, METU, 2008. http://etd.lib.metu.edu.tr/upload/12609885/index.pdf.
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The purpose of this thesis is to search for the best material model for soft biological tissues in general. Different sections of human body exhibit different responses like stress relaxation, creep, hysteresis and preconditioning to external loading conditions. These body sections can be assumed as viscoelastic, poroelastic or pseudoelastic. After making the choice of the material model from one of these for the current study, the finite element model and the material code to be used with this model have been created. The material code has also been tried on a simple finite element model before implementing to the real model to prove the fact that it is
working properly. Then, the constants in the code which simulates the in vivo experimental data that was obtained by indenting the elliptic indenter tip into the forearm, medial part as close as possible, have been derived by inverse finite element method. Consequently, the characteristic behaviors of the soft tissue could be simulated. Despite the big size of the finite element model and very long submission times (up to one day for preconditioning simulation), relaxation and creep behaviors could be simulated with the maximum normalized sum of square errors of 0.74 % and 0.43 %, respectively. The number of square errors for the hysteresis and preconditioning behaviors appeared as 2.56 % and 3.89 % which are also acceptable values. These values prove that these material models are well suited for the simulation of the behavior of soft biological tissues. By using different experimental data obtained from other sections of human body, simulation of the behavior of different soft tissues can be achieved by using these material models.
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Zetterlund, Marie. "Infology : a study to identify possible elements of infology in some system development methodologies." Thesis, University of Skövde, Department of Computer Science, 1999. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-402.
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The purpose of this work is to identify possible elements of infology in some systems development methodologies. To reach the aim two objectives were identified: to gain an understanding of the concept of infology and secondly to study different kinds of methodologies and analyse them to find out possible elements of infology. In order to reach the aim of this work a literature study was performed. Four methodologies were chosen for the analysis and the selection represented a wide range of different methodologies. They were: Soft Systems Methodology (SSM), Effective Technical and Human Implementation of Computer based Systems (ETHICS), Structured Systems Analysis and Design Method (SSADM) and Yourdon Systems Method (YSM). The infological approach has been characterised and the fundamental characteristic of infology is the distinction between data and information. A consequence from this distinction is that the users of the intended information system should participate in the developing process in order to understand the complex and dynamic relations in an organisation and information system. The results of this work have shown that the soft methodologies (SSM and ETHICS) have a high degree of infology and the more hard methodologies (SSADM and YSM) have a low degree of infology.
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Lagervik, Charlie. "A System Theoretical Approach to Situation Awareness : A holistic view of purposeful elements." Thesis, University of Skövde, School of Humanities and Informatics, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-1013.
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From the theories of Ackoff about system theory and how the management of an organization should perform, the concept of situation awareness is discussed. A short history of the situation awareness concept is given in the light of aviation and human cognition. Motives are given why it is of interest to explore the concept of SA. The Russian Theory of Activity (Activity Theory) is presented with the focus on the orientational activity to give the background for a comparison against the adaptive-learning management system as presented by Ackoff. As result a definition of SA is presented, the result of the comparison of theories is presented, discussed and summarized in a conceptual design and future research is presented.
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Lundholm, Karin. "Fate of Cu, Cr, As and some other trace elements during combustion of recovered waste fuels." Doctoral thesis, Umeå : Department of Applied Physics and Electronics, Umeå Univ, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-1132.
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Wang, Wei. "Unveiling Molecular Mechanisms of piRNA Pathway from Small Signals in Big Data: A Dissertation." eScholarship@UMMS, 2015. https://escholarship.umassmed.edu/gsbs_diss/805.
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PIWI-interacting RNAs (piRNA) are a group of 23–35 nucleotide (nt) short RNAs that protect animal gonads from transposon activities. In Drosophila germ line, piRNAs can be categorized into two different categories— primary and secondary piRNAs— based on their origins. Primary piRNAs, generated from transcripts of specific genomic regions called piRNA clusters, which are enriched in transposon fragments that are unlikely to retain transposition activity. The transcription and maturation of primary piRNAs from those cluster transcripts are poorly understood. After being produced, a group of primary piRNAs associates Piwi proteins and directs them to repress transposons at the transcriptional level in the nucleus. Other than their direct role in repressing transposons, primary piRNAs can also initiate the production of secondary piRNA. piRNAs with such function are loaded in a second PIWI protein named Aubergine (Aub). Similar to Piwi, Aub is guided by piRNAs to identify its targets through base-pairing. Differently, Aub functions in the cytoplasm by cleaving transposon mRNAs. The 5' cleavage products are not degraded but loaded into the third PIWI protein Argonaute3 (Ago3). It is believed that an unidentified nuclease trims the 3' ends of those cleavage products to 23–29 nt, becoming mature piRNAs remained in Ago3. Such piRNAs whose 5' ends are generated by another PIWI protein are named secondary piRNAs. Intriguingly, secondary piRNAs loaded into Ago3 also cleave transposon mRNA or piRNA cluster transcripts and produce more secondary piRNAs loaded into Aub. This reciprocal feed-forward loop, named the “Ping-Pong cycle”, amplified piRNA abundance.
By dissecting and analyzing data from large-scale deep sequencing of piRNAs and transposon transcripts, my dissertation research elucidates the biogenesis of germline piRNAs in Drosophila.
How primary piRNAs are processed into mature piRNAs remains enigmatic. I discover that primary piRNA signal on the genome display a fixed periodicity of ~26 nt. Such phasing depends on Zucchini, Armitage and some other primary piRNA pathway components. Further analysis suggests that secondary piRNAs bound to Ago3 can initiate phased primary piRNA production from cleaved transposon RNAs. The first ~26 nt becomes a secondary piRNA that bind Aub while the subsequent piRNAs bind Piwi, allowing piRNAs to spread beyond the site of RNA cleavage. This discovery adds sequence diversity to the piRNA pool, allowing adaptation to changes in transposon sequence. We further find that most Piwi-associated piRNAs are generated from the cleavage products of Ago3, instead of being processed from piRNA cluster transcripts as the previous model suggests. The cardinal function of Ago3 is to produce antisense piRNAs that direct transcriptional silencing by Piwi, rather to make piRNAs that guide post-transcriptional silencing by Aub. Although Ago3 slicing is required to efficiently trigger phased piRNA production, an alternative, slicing-independent pathway suffices to generate Piwi-bound piRNAs that repress transcription of a subset of transposon families. The alternative pathway may help flies silence newly acquired transposons for which they lack extensively complementary piRNAs.
The Ping-Pong model depicts that first ten nucleotides of Aub-bound piRNAs are complementary to the first ten nt of Ago3-bound piRNAs. Supporting this view, piRNAs bound to Aub typically begin with Uridine (1U), while piRNAs bound to Ago3 often have adenine at position 10 (10A). Furthermore, the majority of Ping-Pong piRNAs form this 1U:10A pair. The Ping-Pong model proposes that the 10A is a consequence of 1U. By statistically quantifying those target piRNAs not paired to g1U, we discover that 10A is not directly caused by 1U. Instead, fly Aub as well as its homologs, Siwi in silkmoth and MILI in mice, have an intrinsic preference for adenine at the t1 position of their target RNAs. On the other hand, this t1A (and g10A after loading) piRNA directly give rise to 1U piRNA in the next Ping-Pong cycle, maximizing the affinity between piRNAs and PIWI proteins.
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Wang, Wei. "Unveiling Molecular Mechanisms of piRNA Pathway from Small Signals in Big Data: A Dissertation." eScholarship@UMMS, 2010. http://escholarship.umassmed.edu/gsbs_diss/805.
Full textAbstract:
PIWI-interacting RNAs (piRNA) are a group of 23–35 nucleotide (nt) short RNAs that protect animal gonads from transposon activities. In Drosophila germ line, piRNAs can be categorized into two different categories— primary and secondary piRNAs— based on their origins. Primary piRNAs, generated from transcripts of specific genomic regions called piRNA clusters, which are enriched in transposon fragments that are unlikely to retain transposition activity. The transcription and maturation of primary piRNAs from those cluster transcripts are poorly understood. After being produced, a group of primary piRNAs associates Piwi proteins and directs them to repress transposons at the transcriptional level in the nucleus. Other than their direct role in repressing transposons, primary piRNAs can also initiate the production of secondary piRNA. piRNAs with such function are loaded in a second PIWI protein named Aubergine (Aub). Similar to Piwi, Aub is guided by piRNAs to identify its targets through base-pairing. Differently, Aub functions in the cytoplasm by cleaving transposon mRNAs. The 5' cleavage products are not degraded but loaded into the third PIWI protein Argonaute3 (Ago3). It is believed that an unidentified nuclease trims the 3' ends of those cleavage products to 23–29 nt, becoming mature piRNAs remained in Ago3. Such piRNAs whose 5' ends are generated by another PIWI protein are named secondary piRNAs. Intriguingly, secondary piRNAs loaded into Ago3 also cleave transposon mRNA or piRNA cluster transcripts and produce more secondary piRNAs loaded into Aub. This reciprocal feed-forward loop, named the “Ping-Pong cycle”, amplified piRNA abundance.
By dissecting and analyzing data from large-scale deep sequencing of piRNAs and transposon transcripts, my dissertation research elucidates the biogenesis of germline piRNAs in Drosophila.
How primary piRNAs are processed into mature piRNAs remains enigmatic. I discover that primary piRNA signal on the genome display a fixed periodicity of ~26 nt. Such phasing depends on Zucchini, Armitage and some other primary piRNA pathway components. Further analysis suggests that secondary piRNAs bound to Ago3 can initiate phased primary piRNA production from cleaved transposon RNAs. The first ~26 nt becomes a secondary piRNA that bind Aub while the subsequent piRNAs bind Piwi, allowing piRNAs to spread beyond the site of RNA cleavage. This discovery adds sequence diversity to the piRNA pool, allowing adaptation to changes in transposon sequence. We further find that most Piwi-associated piRNAs are generated from the cleavage products of Ago3, instead of being processed from piRNA cluster transcripts as the previous model suggests. The cardinal function of Ago3 is to produce antisense piRNAs that direct transcriptional silencing by Piwi, rather to make piRNAs that guide post-transcriptional silencing by Aub. Although Ago3 slicing is required to efficiently trigger phased piRNA production, an alternative, slicing-independent pathway suffices to generate Piwi-bound piRNAs that repress transcription of a subset of transposon families. The alternative pathway may help flies silence newly acquired transposons for which they lack extensively complementary piRNAs.
The Ping-Pong model depicts that first ten nucleotides of Aub-bound piRNAs are complementary to the first ten nt of Ago3-bound piRNAs. Supporting this view, piRNAs bound to Aub typically begin with Uridine (1U), while piRNAs bound to Ago3 often have adenine at position 10 (10A). Furthermore, the majority of Ping-Pong piRNAs form this 1U:10A pair. The Ping-Pong model proposes that the 10A is a consequence of 1U. By statistically quantifying those target piRNAs not paired to g1U, we discover that 10A is not directly caused by 1U. Instead, fly Aub as well as its homologs, Siwi in silkmoth and MILI in mice, have an intrinsic preference for adenine at the t1 position of their target RNAs. On the other hand, this t1A (and g10A after loading) piRNA directly give rise to 1U piRNA in the next Ping-Pong cycle, maximizing the affinity between piRNAs and PIWI proteins.
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Moulin, Serge. "Use of data analysis techniques to solve specific bioinformatics problems." Thesis, Bourgogne Franche-Comté, 2018. http://www.theses.fr/2018UBFCD049/document.
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De nos jours, la quantité de données génétiques séquencées augmente de manière exponentielle sous l'impulsion d'outils de séquençage de plus en plus performants, tels que les outils de séquençage haut débit en particulier. De plus, ces données sont de plus en plus facilement accessibles grâce aux bases de données en ligne. Cette plus grande disponibilité des données ouvre de nouveaux sujets d'étude qui nécessitent de la part des statisticiens et bio-informaticiens de développer des outils adaptés. Par ailleurs, les progrès constants de la statistique, dans des domaines tels que le clustering, la réduction de dimension, ou les régressions entre autres, nécessitent d'être régulièrement adaptés au contexte de la bio-informatique. L’objectif de cette thèse est l’application de techniques avancées de statistiques à des problématiques de bio-informatique. Dans ce manuscrit, nous présentons les résultats de nos travaux concernant le clustering de séquences génétiques via Laplacian eigenmaps et modèle de mélange gaussien, l'étude de la propagation des éléments transposables dans le génome via un processus de branchement, l'analyse de données métagénomiques en écologie via des courbes ROC ou encore la régression polytomique ordonnée pénalisée par la norme l1Nowadays, the quantity of sequenced genetic data is increasing exponentially under the impetus of increasingly powerful sequencing tools, such as high-throughput sequencing tools in particular. In addition, these data are increasingly accessible through online databases. This greater availability of data opens up new areas of study that require statisticians and bioinformaticians to develop appropriate tools. In addition, constant statistical progress in areas such as clustering, dimensionality reduction, regressions and others needs to be regularly adapted to the context of bioinformatics. The objective of this thesis is the application of advanced statistical techniques to bioinformatics issues. In this manuscript we present the results of our works concerning the clustering of genetic sequences via Laplacian eigenmaps and Gaussian mixture model, the study of the propagation of transposable elements in the genome via a branching process, the analysis of metagenomic data in ecology via ROC curves or the ordinal polytomous regression penalized by the l1-norm
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Hellman, Fredrik. "Numerical Methods for Darcy Flow Problems with Rough and Uncertain Data." Doctoral thesis, Uppsala universitet, Avdelningen för beräkningsvetenskap, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-318589.
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We address two computational challenges for numerical simulations of Darcy flow problems: rough and uncertain data. The rapidly varying and possibly high contrast permeability coefficient for the pressure equation in Darcy flow problems generally leads to irregular solutions, which in turn make standard solution techniques perform poorly. We study methods for numerical homogenization based on localized computations. Regarding the challenge of uncertain data, we consider the problem of forward propagation of uncertainty through a numerical model. More specifically, we consider methods for estimating the failure probability, or a point estimate of the cumulative distribution function (cdf) of a scalar output from the model. The issue of rough coefficients is discussed in Papers I–III by analyzing three aspects of the localized orthogonal decomposition (LOD) method. In Paper I, we define an interpolation operator that makes the localization error independent of the contrast of the coefficient. The conditions for its applicability are studied. In Paper II, we consider time-dependent coefficients and derive computable error indicators that are used to adaptively update the multiscale space. In Paper III, we derive a priori error bounds for the LOD method based on the Raviart–Thomas finite element. The topic of uncertain data is discussed in Papers IV–VI. The main contribution is the selective refinement algorithm, proposed in Paper IV for estimating quantiles, and further developed in Paper V for point evaluation of the cdf. Selective refinement makes use of a hierarchy of numerical approximations of the model and exploits computable error bounds for the random model output to reduce the cost complexity. It is applied in combination with Monte Carlo and multilevel Monte Carlo methods to reduce the overall cost. In Paper VI we quantify the gains from applying selective refinement to a two-phase Darcy flow problem.
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LEE, SEUNG M. "Um estudo sobre metodos de calculo e medidas experimentais de parametros cineticos em sistemas subcriticos acionados por fonte." reponame:Repositório Institucional do IPEN, 2009. http://repositorio.ipen.br:8080/xmlui/handle/123456789/9385.
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Made available in DSpace on 2014-10-09T12:26:24Z (GMT). No. of bitstreams: 0Made available in DSpace on 2014-10-09T14:04:32Z (GMT). No. of bitstreams: 0
Dissertacao (Mestrado)
IPEN/D
Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
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Maaroufi, Meriem. "Interopérabilité des données médicales dans le domaine des maladies rares dans un objectif de santé publique." Thesis, Paris 6, 2016. http://www.theses.fr/2016PA066275/document.
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La santé se digitalise et de multiples projets d’e-santé se développent. Dans le contexte des maladies rares (MR), un champ qui est devenu parmi les priorités de la stratégie de santé publique en France, l’e-santé pourrait constituer une solution pour améliorer les connaissances sur l’épidémiologie des MR. La Banque Nationale de Données Maladies Rares (BNDMR) propose de centraliser la conduite de ces études épidémiologiques pour toutes les MR et tous les patients, atteints de ces maladies, suivis dans le système de soin français. La BNDMR doit se développer au sein d’un paysage numérique dense et hétérogène. Développer l’interopérabilité de la BNDMR constitue l’objectif des travaux de cette thèse. Comment identifier les patients, incluant les fœtus ? Comment fédérer les identités des patients? Comment chainer des données pour permettre la conduite des études ? En réponse à ces questions, nous proposons une méthode universelle d’identification des patients qui respecte les contraintes de protection des données de santé. Quelles données recueillir dans la BNDMR ? Comment améliorer l’interopérabilité entre ces données et celles issues du large éventail des systèmes existants ? En réponse à ces questions, nous proposons de standardiser le recueil d’un set minimal de données pour toutes les MR. L’implémentation de standards internationaux assure un premier pas vers l’interopérabilité. Nous proposons aussi d’aller à la découverte de correspondances. Minimiser l’intervention humaine en adoptant des techniques d’alignement automatisé et rendre fiables et exploitables les résultats de ces alignements ont constitué les principales motivations de notre propositionThe digitalization of healthcare is on and multiple e-health projects are unceasingly coming up. In the rare diseases context, a field that has become a public health policy priority in France, e-health could be a solution to improve rare diseases epidemiology and to propose a better care for patients. The national data bank for rare diseases (BNDMR) offers the centralization of these epidemiological studies conduction for all rare diseases and all affected patients followed in the French healthcare system. The BNDMR must grow in a dense and heterogeneous digital landscape. Developing the BNDMR interoperability is the objective of this thesis’ work. How to identify patients, including fetuses? How to federate patients’ identities to avoid duplicates creation? How to link patients’ data to allow studies’ conduction? In response to these questions, we propose a universal method for patients’ identification that meets the requirements of health data protection. Which data should be collected in the national data bank? How to improve and facilitate the development of interoperability between these data and those from the wide range of the existing systems? In response to these questions, we first propose the collection of a standardized minimum data set for all rare diseases. The implementation of international standards provides a first step toward interoperability. We then propose to move towards the discovery of mappings between heterogeneous data sources. Minimizing human intervention by adopting automated alignment techniques and making these alignments’ results reliable and exploitable were the main motivations of our proposal
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Arsenteva, Polina. "Statistical modeling and analysis of radio-induced adverse effects based on in vitro and in vivo data." Electronic Thesis or Diss., Bourgogne Franche-Comté, 2023. http://www.theses.fr/2023UBFCK074.
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Dans ce travail nous abordons le problème des effets indésirables induits par la radiothérapie sur les tissus sains. L'objectif est de proposer un cadre mathématique pour comparer les effets de différentes modalités d'irradiation, afin de pouvoir éventuellement choisir les traitements qui produisent le moins d'effets indésirables pour l’utilisation potentielle en clinique. Les effets secondaires sont étudiés dans le cadre de deux types de données : en termes de réponse omique in vitro des cellules endothéliales humaines, et en termes d'effets indésirables observés sur des souris dans le cadre d'expérimentations in vivo. Dans le cadre in vitro, nous rencontrons le problème de l'extraction d'informations clés à partir de données temporelles complexes qui ne peuvent pas être traitées avec les méthodes disponibles dans la littérature. Nous modélisons le fold change radio-induit, l'objet qui code la différence d'effet de deux conditions expérimentales, d’une manière qui permet de prendre en compte les incertitudes des mesures ainsi que les corrélations entre les entités observées. Nous construisons une distance, avec une généralisation ultérieure à une mesure de dissimilarité, permettant de comparer les fold changes en termes de toutes leurs propriétés statistiques importantes. Enfin, nous proposons un algorithme computationnellement efficace effectuant le clustering joint avec l'alignement temporel des fold changes. Les caractéristiques clés extraites de ces dernières sont visualisées à l'aide de deux types de représentations de réseau, dans le but de faciliter l'interprétation biologique. Dans le cadre in vivo, l’enjeu statistique est d’établir un lien prédictif entre des variables qui, en raison des spécificités du design expérimental, ne pourront jamais être observées sur les mêmes animaux. Dans le contexte de ne pas avoir accès aux lois jointes, nous exploitons les informations supplémentaires sur les groupes observés pour déduire le modèle de régression linéaire. Nous proposons deux estimateurs des paramètres de régression, l'un basé sur la méthode des moments et l'autre basé sur le transport optimal, ainsi que des estimateurs des intervalles de confiance basés sur le bootstrap stratifiéIn this work we address the problem of adverse effects induced by radiotherapy on healthy tissues. The goal is to propose a mathematical framework to compare the effects of different irradiation modalities, to be able to ultimately choose those treatments that produce the minimal amounts of adverse effects for potential use in the clinical setting. The adverse effects are studied in the context of two types of data: in terms of the in vitro omic response of human endothelial cells, and in terms of the adverse effects observed on mice in the framework of in vivo experiments. In the in vitro setting, we encounter the problem of extracting key information from complex temporal data that cannot be treated with the methods available in literature. We model the radio-induced fold change, the object that encodes the difference in the effect of two experimental conditions, in the way that allows to take into account the uncertainties of measurements as well as the correlations between the observed entities. We construct a distance, with a further generalization to a dissimilarity measure, allowing to compare the fold changes in terms of all the important statistical properties. Finally, we propose a computationally efficient algorithm performing clustering jointly with temporal alignment of the fold changes. The key features extracted through the latter are visualized using two types of network representations, for the purpose of facilitating biological interpretation. In the in vivo setting, the statistical challenge is to establish a predictive link between variables that, due to the specificities of the experimental design, can never be observed on the same animals. In the context of not having access to joint distributions, we leverage the additional information on the observed groups to infer the linear regression model. We propose two estimators of the regression parameters, one based on the method of moments and the other based on optimal transport, as well as the estimators for the confidence intervals based on the stratified bootstrap procedure
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Weber, Daniel Verfasser], André [Akademischer Betreuer] Stork, Dieter W. [Akademischer Betreuer] [Fellner, and Michael [Akademischer Betreuer] Goesele. "Interactive Physically Based Simulation - Efficient Higher-Order Elements, Multigrid Approaches and Massively Parallel Data Structures / Daniel Weber. Betreuer: André Stork ; Dieter Fellner ; Michael Goesele." Darmstadt : Universitäts- und Landesbibliothek Darmstadt, 2016. http://d-nb.info/1112141847/34.
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Weber, Daniel [Verfasser], André Akademischer Betreuer] Stork, Dieter W. [Akademischer Betreuer] [Fellner, and Michael [Akademischer Betreuer] Goesele. "Interactive Physically Based Simulation - Efficient Higher-Order Elements, Multigrid Approaches and Massively Parallel Data Structures / Daniel Weber. Betreuer: André Stork ; Dieter Fellner ; Michael Goesele." Darmstadt : Universitäts- und Landesbibliothek Darmstadt, 2016. http://nbn-resolving.de/urn:nbn:de:tuda-tuprints-53257.
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