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Stabilité du développement et stress environnemental : analyse morphométrique du fémur de l’homme / Developmental stability and environmental stress : a geometric morphometrics analysis of the human femurMopin, Clémence 21 January 2019 (has links)
Parmi les approches employées pour caractériser l’état sanitaire des populations antérieures, l’utilisation de l’asymétrie fluctuante (AF) pour rendre compte de la stabilité de développement (DS) du squelette est rare. Après plus d’un demi-siècle de recherches, la DS reste assez méconnue chez l’Homme. Aujourd’hui, les techniques de morphométrie géométrique permettent de quantifier plus finement les variations en analysant de nouveaux aspects morphologiques en 3D.Les objectifs de ce travail étaient:1-Déterminer si l’analyse morpho-géométrique de l’AF chez l’Homme permet de distinguer deux populations.2-Établir si cette distinction peut être attribuée à une différence d’état sanitaire.Les données de deux populations caractérisées par des contextes sanitaires distincts ont été confrontées. Deux échantillons de 70 paires de fémurs adultes d'âge et de sexe comparables ont été sélectionnés. Vingt-sept points-repères ont été positionnés sur chaque surface osseuse reconstruite en 3D. L’AF a été analysée en termes d’amplitude et de localisation sur le fémur.Finalement, cette analyse morpho-géométrique a permis de distinguer deux populations au contextes sanitaires distincts. La population la moins favorisée a exprimé un degré d’AF plus élevé. Considérant l’impact des facteurs potentiels de variation, le stress sanitaire explique le mieux les perturbations de la DS. Au vu de la localisation de l’AF sur le fémur, le facteur biomécanique semble aussi jouer un rôle relatif. Chez l’Homme, la localisation de l’asymétrie fluctuante peut donc être dirigée en partie par les contraintes biomécaniques, cependant son amplitude est principalement influencée par le stress sanitaire. / Among the approaches used to characterize the health status in past populations, the use of fluctuating asymmetry (FA) to evaluate developmental stability (DS) in bone is rare. After more than half a century of research, DS remains relatively unknown in humans. Today, geometric morphometrics techniques offer new perspectives. It is now possible to quantify variations more precisely and approach them by analyzing a new morphological element: shape.The aim of this work was twofold:1-Determine whether the geometric morphometrics analysis of FA in humans can distinguish two populations.2-Determine whether this distinction can be attributed to a difference in health status.The data of two populations of known and distinct health statuses and environmental contexts were compared. Two samples of 70 pairs of adult femurs of comparable age and sex were selected. Two sets of 27 landmarks were placed on the 3D isosurfaces of each femur. FA was analyzed and characterized in terms of range of magnitude and pattern of expression in the femur.Finally, this geometric morphometrics analysis allowed to distinguish two populations that have developed under distinct environmental conditions. The population that experienced higher levels of stress expressed a higher degree of FA. After considering the impact of potential factors of variation, the health stress seems to best explain disturbances of DS. However, given its pattern of expression on the femur, the biomechanical factor seems to play also a relative role. Therefore, in humans, the pattern of expression of FA is directed in part by biomechanical constraints but its magnitude remains mostly influenced by health stress.
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Semantic Enrichment of Ontology MappingsArnold, Patrick 15 December 2015 (has links)
Schema and ontology matching play an important part in the field of data integration and semantic web. Given two heterogeneous data sources, meta data matching usually constitutes the first step in the data integration workflow, which refers to the analysis and comparison of two input resources like schemas or ontologies. The result is a list of correspondences between the two schemas or ontologies, which is often called mapping or alignment. Many tools and research approaches have been proposed to automatically determine those correspondences. However, most match tools do not provide any information about the relation type that holds between matching concepts, for the simple but important reason that most common match strategies are too simple and heuristic to allow any sophisticated relation type determination.
Knowing the specific type holding between two concepts, e.g., whether they are in an equality, subsumption (is-a) or part-of relation, is very important for advanced data integration tasks, such as ontology merging or ontology evolution. It is also very important for mappings in the biological or biomedical domain, where is-a and part-of relations may exceed the number of equality correspondences by far. Such more expressive mappings allow much better integration results and have scarcely been in the focus of research so far.
In this doctoral thesis, the determination of the correspondence types in a given mapping is the focus of interest, which is referred to as semantic mapping enrichment. We introduce and present the mapping enrichment tool STROMA, which obtains a pre-calculated schema or ontology mapping and for each correspondence determines a semantic relation type. In contrast to previous approaches, we will strongly focus on linguistic laws and linguistic insights. By and large, linguistics is the key for precise matching and for the determination of relation types. We will introduce various strategies that make use of these linguistic laws and are able to calculate the semantic type between two matching concepts. The observations and insights gained from this research go far beyond the field of mapping enrichment and can be also applied to schema and ontology matching in general.
Since generic strategies have certain limits and may not be able to determine the relation type between more complex concepts, like a laptop and a personal computer, background knowledge plays an important role in this research as well. For example, a thesaurus can help to recognize that these two concepts are in an is-a relation. We will show how background knowledge can be effectively used in this instance, how it is possible to draw conclusions even if a concept is not contained in it, how the relation types in complex paths can be resolved and how time complexity can be reduced by a so-called bidirectional search. The developed techniques go far beyond the background knowledge exploitation of previous approaches, and are now part of the semantic repository SemRep, a flexible and extendable system that combines different lexicographic resources.
Further on, we will show how additional lexicographic resources can be developed automatically by parsing Wikipedia articles. The proposed Wikipedia relation extraction approach yields some millions of additional relations, which constitute significant additional knowledge for mapping enrichment. The extracted relations were also added to SemRep, which thus became a comprehensive background knowledge resource. To augment the quality of the repository, different techniques were used to discover and delete irrelevant semantic relations.
We could show in several experiments that STROMA obtains very good results w.r.t. relation type detection. In a comparative evaluation, it was able to achieve considerably better results than related applications. This corroborates the overall usefulness and strengths of the implemented strategies, which were developed with particular emphasis on the principles and laws of linguistics.
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Federated Product Information Search and Semantic Product Comparisons on the WebWalther, Maximilian Thilo 09 September 2011 (has links)
Product information search has become one of the most important application areas of the Web. Especially considering pricey technical products, consumers tend to carry out intensive research activities previous to the actual acquisition for creating an all-embracing view on the product of interest. Federated search backed by ontology-based product information representation shows great promise for easing this research process.
The topic of this thesis is to develop a comprehensive technique for locating, extracting, and integrating information of arbitrary technical products in a widely unsupervised manner. The resulting homogeneous information sets allow a potential consumer to effectively compare technical products based on an appropriate federated product information system.:1. Introduction
1.1. Online Product Information Research
1.1.1. Current Online Product Information Research
1.1.2. Aspired Online Product Information Research
1.2. Federated Shopping Portals
1.3. Research Questions
1.4. Approach and Theses
1.4.1. Approach
1.4.2. Theses
1.4.3. Requirements
1.5. Goals and Non-Goals
1.5.1. Goals
1.5.2. Non-Goals
1.6. Contributions
1.7. Structure
2. Federated Information Systems
2.1. Information Access
2.1.1. Document Retrieval
2.1.2. Federated Search
2.1.3. Federated Ranking
2.2. Information Extraction
2.2.1. Information Extraction from Structured Sources
2.2.2. Information Extraction from Unstructured Sources
2.2.3. Information Extraction from Semi-structured Sources
2.3. Information Integration
2.3.1. Ontologies
2.3.2. Ontology Matching
2.4. Information Presentation
2.5. Product Information
2.5.1. Product Information Source Characteristics
2.5.2. Product Information Source Types
2.5.3. Product Information Integration Types
2.5.4. Product Information Types
2.6. Conclusions
3. A Federated Product Information System
3.1. Finding Basic Product Information
3.2. Enriching Product Information
3.3. Administrating Product Information
3.4. Displaying Product Information
3.5. Conclusions
4. Product Information Extraction from the Web
4.1. Vendor Product Information Search
4.1.1. Vendor Product Information Ranking
4.1.2. Vendor Product Information Extraction
4.2. Producer Product Information Search
4.2.1. Producer Product Document Retrieval
4.2.2. Producer Product Information Extraction
4.3. Third-Party Product Information Search
4.4. Conclusions
5. Product Information Integration for the Web
5.1. Product Representation
5.1.1. Domain Product Ontology
5.1.2. Application Product Ontology
5.1.3. Product Ontology Management
5.2. Product Categorization
5.3. Product Specifications Matching
5.3.1. General Procedure
5.3.2. Elementary Matchers
5.3.3. Evolutionary Matcher
5.3.4. Naïve Bayes Matcher
5.3.5. Result Selection
5.4. Product Specifications Normalization
5.4.1. Product Specifications Atomization
5.4.2. Product Specifications Value Normalization
5.5. Product Comparison
5.6. Conclusions
6. Evaluation
6.1. Implementation
6.1.1. Offers Service
6.1.2. Products Service
6.1.3. Snippets Service
6.1.4. Fedseeko
6.1.5. Fedseeko Browser Plugin
6.1.6. Fedseeko Mobile
6.1.7. Lessons Learned
6.2. Evaluation
6.2.1. Evaluation Measures
6.2.2. Gold Standard
6.2.3. Product Document Retrieval
6.2.4. Product Specifications Extraction
6.2.5. Product Specifications Matching
6.2.6. Comparison with Competitors
6.3. Conclusions
7. Conclusions and Future Work
7.1. Summary
7.2. Conclusions
7.3. Future Work
A. Pseudo Code and Extraction Properties
A.1. Pseudo Code
A.2. Extraction Algorithm Properties
A.2.1. Clustering Properties
A.2.2. Purging Properties
A.2.3. Dropping Properties
B. Fedseeko Screenshots
B.1. Offer Search
B.2. Product Comparison / Die Produktinformationssuche hat sich zu einem der bedeutendsten Themen im Web entwickelt. Speziell im Bereich kostenintensiver technischer Produkte führen potenzielle Konsumenten vor dem eigentlichen Kauf des Produkts langwierige Recherchen durch um einen umfassenden Überblick für das Produkt von Interesse zu erlangen. Die föderierte Suche in Kombination mit ontologiebasierter Produktinformationsrepräsentation stellt eine mögliche Lösung dieser Problemstellung dar.
Diese Dissertation stellt Techniken vor, die das automatische Lokalisieren, Extrahieren und Integrieren von Informationen für beliebige technische Produkte ermöglichen. Die resultierenden homogenen Produktinformationen erlauben einem potenziellen Konsumenten, zugehörige Produkte effektiv über ein föderiertes Produktinformationssystem zu vergleichen.:1. Introduction
1.1. Online Product Information Research
1.1.1. Current Online Product Information Research
1.1.2. Aspired Online Product Information Research
1.2. Federated Shopping Portals
1.3. Research Questions
1.4. Approach and Theses
1.4.1. Approach
1.4.2. Theses
1.4.3. Requirements
1.5. Goals and Non-Goals
1.5.1. Goals
1.5.2. Non-Goals
1.6. Contributions
1.7. Structure
2. Federated Information Systems
2.1. Information Access
2.1.1. Document Retrieval
2.1.2. Federated Search
2.1.3. Federated Ranking
2.2. Information Extraction
2.2.1. Information Extraction from Structured Sources
2.2.2. Information Extraction from Unstructured Sources
2.2.3. Information Extraction from Semi-structured Sources
2.3. Information Integration
2.3.1. Ontologies
2.3.2. Ontology Matching
2.4. Information Presentation
2.5. Product Information
2.5.1. Product Information Source Characteristics
2.5.2. Product Information Source Types
2.5.3. Product Information Integration Types
2.5.4. Product Information Types
2.6. Conclusions
3. A Federated Product Information System
3.1. Finding Basic Product Information
3.2. Enriching Product Information
3.3. Administrating Product Information
3.4. Displaying Product Information
3.5. Conclusions
4. Product Information Extraction from the Web
4.1. Vendor Product Information Search
4.1.1. Vendor Product Information Ranking
4.1.2. Vendor Product Information Extraction
4.2. Producer Product Information Search
4.2.1. Producer Product Document Retrieval
4.2.2. Producer Product Information Extraction
4.3. Third-Party Product Information Search
4.4. Conclusions
5. Product Information Integration for the Web
5.1. Product Representation
5.1.1. Domain Product Ontology
5.1.2. Application Product Ontology
5.1.3. Product Ontology Management
5.2. Product Categorization
5.3. Product Specifications Matching
5.3.1. General Procedure
5.3.2. Elementary Matchers
5.3.3. Evolutionary Matcher
5.3.4. Naïve Bayes Matcher
5.3.5. Result Selection
5.4. Product Specifications Normalization
5.4.1. Product Specifications Atomization
5.4.2. Product Specifications Value Normalization
5.5. Product Comparison
5.6. Conclusions
6. Evaluation
6.1. Implementation
6.1.1. Offers Service
6.1.2. Products Service
6.1.3. Snippets Service
6.1.4. Fedseeko
6.1.5. Fedseeko Browser Plugin
6.1.6. Fedseeko Mobile
6.1.7. Lessons Learned
6.2. Evaluation
6.2.1. Evaluation Measures
6.2.2. Gold Standard
6.2.3. Product Document Retrieval
6.2.4. Product Specifications Extraction
6.2.5. Product Specifications Matching
6.2.6. Comparison with Competitors
6.3. Conclusions
7. Conclusions and Future Work
7.1. Summary
7.2. Conclusions
7.3. Future Work
A. Pseudo Code and Extraction Properties
A.1. Pseudo Code
A.2. Extraction Algorithm Properties
A.2.1. Clustering Properties
A.2.2. Purging Properties
A.2.3. Dropping Properties
B. Fedseeko Screenshots
B.1. Offer Search
B.2. Product Comparison
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Product Matching Using Image SimilarityForssell, Melker, Janér, Gustav January 2020 (has links)
PriceRunner is an online shopping comparison company. To maintain up-todate prices, PriceRunner has to process large amounts of data every day. The processing of the data includes matching unknown products, referred to as offers, to known products. Offer data includes information about the product such as: title, description, price and often one image of the product. PriceRunner has previously implemented a textual-based machine learning (ML) model, but is also looking for new approaches to complement the current product matching system. The objective of this master’s thesis is to investigate the potential of using an image-based ML model for product matching. Our method uses a similarity learning approach where the network learns to recognise the similarity between images. To achieve this, a siamese neural network was trained with the triplet loss function. The network is trained to map similar images closer together and dissimilar images further apart in a vector space. This approach is often used for face recognition, where there is an extensive amount of classes and a limited amount of images per class, and new classes are frequently added. This is also the case for the image data used in this thesis project. A general model was trained on images from the Clothing and Accessories hierarchy, one of the 16 toplevel hierarchies at PriceRunner, consisting of 17 product categories. The results varied between each product category. Some categories proved to be less suitable for image-based classification while others excelled. The model handles new classes relatively well without any, or with briefer, retraining. It was concluded that there is potential in using images to complement the current product matching system at PriceRunner.
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Adaptive Losses for Camera Pose SupervisionDahlqvist, Marcus January 2021 (has links)
This master thesis studies the learning of dense feature descriptors where camera poses are the only supervisory signal. The use of camera poses as a supervisory signal has only been published once before, and this thesis expands on this previous work by utilizing a couple of different techniques meant increase the robustness of the method, which is particularly important when not having access to ground-truth correspondences. Firstly, an adaptive robust loss is utilized to better differentiate inliers and outliers. Secondly, statistical properties during training are both enforced and adapted to, in an attempt to alleviate problems with uncertainties introduced by not having true correspondences available. These additions are shown to slightly increase performance, and also highlights some key ideas related to prediction certainty and robustness when working with camera poses as a supervisory signal. Finally, possible directions for future work are discussed.
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Intergiciel agent pour le déploiement et la configuration d'applications distribuées dans des environnements ambiants / An agent middleware for the deployment and the configuration of distributed applications in ambient environmentsPiette, Ferdinand 17 January 2017 (has links)
L'évolution des technologies de l'information ainsi que la miniaturisation constante des composants électroniques de ces dernières décennies ont permis de doter les objets de la vie de tous les jours de capacités de calcul et de communication. Ces objets connectés sont disséminés dans l'environnement de l'utilisateur et coopèrent les uns avec les autres afin de fournir à l'utilisateur des services intelligents de manière totalement transparente et non intrusive. Ces environnements sont caractérisés par une grande hétérogénéité ainsi qu'une grande dynamicité. Les intégrations dites verticales (les données des capteurs sont externalisées sur les serveurs d'une entreprise) permettent certes une interopérabilité plus importante, mais engendrent des problèmes de saturation des canaux de communication, ainsi que des questionnements sur la sécurité et la confidentialité de des informations. Pour pallier ces problèmes, les intégrations dites horizontales (les entités matérielles sont mises en relation directement au sein de l'infrastructure) sont encouragées. Dans cette thèse, nous adressons le problème du déploiement et de la configuration automatique d'applications au sein de tels environnements ambiants. Nous proposons des mécanismes permettant, à partir d'une description de l'environnement ambiant, la sélection et la configuration d'entités matérielles qui supporteront l'exécution des applications. Ces mécanismes ont été encapsulé dans un intergiciel basé sur le paradigme Multi-agents dans lequel les différents agents logiciels du système collaborent afin de sélectionner les entités de l'infrastructure respectant les besoins et les contraintes des applications à déployer. / Research domains like Ambient Intelligence or Internet of Things came up in the early 2000’s with the technologic improvement and the ongoing miniaturization of electronic devices. These electronic and information devices are scattered in the user’s environment, can communicate and exchange data more and more easily to provide intelligent and non-intrusive services to the users. However, it is difficult to have generic implementations of these applications. These difficulties are due the the high heterogeneity and dynamicity of the ambient environments. Vertical integrations of connected devices (data exchanges from the devices to external servers) allow more interoperability but generate overloads of the communication channels and privacy concerns. To prevent these problems, horizontal approaches (connected devices communicate directly together through the hardware infrastructure) have to be encouraged. In this thesis work, we address the problem of the automatic deployment and configuration of distributed applications in these ambient environments. We propose mechanisms that allow, from a description of the environment, the selection and the configuraion of the hardware entities that will support the execution of applications. These mechanisms are encapsulated in a middleware based on the multi-agent paradigm. The different agents of the system cooperate in order to select the right hardware entities that respects the requirements and the constraints of the applications we want to deploy.
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Image Stitching and Matching Tool in the Automated Iterative Reverse Engineer (AIRE) Integrated Circuit Analysis SuiteBowman, David C. 24 August 2018 (has links)
No description available.
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Odhad varianční matice pro filtraci ve vysoké dimenzi / Covariance estimation for filtering in high dimensionTurčičová, Marie January 2021 (has links)
Estimating large covariance matrices from small samples is an important problem in many fields. Among others, this includes spatial statistics and data assimilation. In this thesis, we deal with several methods of covariance estimation with emphasis on regula- rization and covariance models useful in filtering problems. We prove several properties of estimators and propose a new filtering method. After a brief summary of basic esti- mating methods used in data assimilation, the attention is shifted to covariance models. We show a distinct type of hierarchy in nested models applied to the spectral diagonal covariance matrix: explicit estimators of parameters are computed by the maximum like- lihood method and asymptotic variance of these estimators is shown to decrease when the maximization is restricted to a subspace that contains the true parameter value. A similar result is obtained for general M-estimators. For more complex covariance mo- dels, maximum likelihood method cannot provide explicit parameter estimates. In the case of a linear model for a precision matrix, however, consistent estimator in a closed form can be computed by the score matching method. Modelling of the precision ma- trix is particularly beneficial in Gaussian Markov random fields (GMRF), which possess a sparse precision matrix. The...
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Comparing soft body simulations using extended position-based dynamics and shape matchingWestergren, Erik January 2022 (has links)
Today, soft body simulations are essential for a wide range of applications. They are for instance used for medical training in virtual reality and in video games to simulate clothes and hair. These kinds of interactive applications rely on real-time simulations, which entails very strict requirements. The simulation has to be fast enough and must never break, regardless of what deformation might occur. Two methods that perform well with regard to these requirements are the position-based dynamics (PBD) method and the shape matching method. Even though these methods have been used for years, it is still unclear when you should use either method. This thesis has compared the two methods with regard to the mentioned requirements. More specifically, the thesis has evaluated the performance of the simulation loop as well as the simulated objects’ ability to restore their shape after deformation. The performance results clearly show that the PBD method is the fastest. But the results of the simulated objects’ ability to restore their shape were not as conclusive. Overall, the PBD method seemed to perform the best again, but there were cases the method could not handle. Although the shape matching method performed slightly worse, it did manage to restore the shape of every deformed object. In conclusion, for most applications, the PBD method is likely the better option, but if the application relies on the fact that simulated objects can restore their shape, then the shape matching method may be preferable. / Idag är simulering av mjuka kroppar viktiga för en mängd olika tillämpningar. De används exempelvis för medicinsk träning i virtuell verklighet och i datorspel för att simulera kläder och hår. Dessa typer av interaktiva applikationer förlitar sig på realtidssimuleringar, vilket medför många stränga krav. Simuleringen måste vara tillräckligt snabb och får aldrig gå sönder, oavsett vad för slags deformation som kan uppstå. Två metoder som presterar bra med avseende på dessa krav är position-based dynamics (PBD) och shape matching. Trots att dessa metoder har använts i många år, så är det fortfarande oklart när vilken metod är mest lämplig. Denna avhandling har jämfört de två metoderna med hänsyn till de nämnda kraven. Mer specifikt har avhandlingen utvärderat metodernas prestanda samt de simulerade objektens förmåga att återställa sin form efter deformation. Resultaten för prestanda visar tydligt att PBD-metoden är snabbast. Men resultaten av de simulerade objektens förmåga att återställa sin form var inte lika enhälliga. Sammantaget verkade PBD-metoden prestera bäst igen, däremot fanns det fall som metoden inte kunde hantera. Fastän shape matching metoden presterade något sämre, så lyckades den återställa formen för varje deformerat objekt. Sammanfattningsvis, för de flesta applikationer är PBD-metoden troligen det bättre alternativet, men om applikationen förlitar sig på att de simulerade objekten kan återställa sina former, så kan shape matching metoden vara att föredra.
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Matching Concept Descriptions with Existential Restrictions RevisitedBaader, Franz, Küsters, Ralf 20 May 2022 (has links)
Matching of concepts against patterns is a new inference task in Description Logics, which was originally motivated by applications of the CLASSIC system. Consequently, the work on this problem was until now mostly concerned with sublanguages of the Classic language, which does not allow for existential restrictions. Motivated by an application in chemical process engineering, which requires a description language with existential restrictions, this paper investigates the matching problem in Description Logics with existential restrictions. It turns out that existential restrictions make matching more complex in two respects. First, whereas matching in sublanguages of CLASSIC is polynomial, deciding the existence of matchers is an NP-complete problem in the presence of existential restrictions. Second, whereas in sublanguages of Classic solvable matching problems have a unique least matcher, this is not the case for languages with existential restrictions. Thus, it is not a priori clear which of the (possibly infinitely many) matchers should be returned by a matching algorithm. After determining the complexity of the decision problem, the present paper first investigates the question of what are 'interesting' sets of matchers, and then describes algorithms for computing these sets for the languages EL (which allows for conjunction and existential restrictions) and ALE (which additionally allows for value restrictions, primitive negation, and the bottom concept). / An abridged version of this technical report has been submitted to KR 2000.
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