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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
681

Evaluating GraphQL over REST within an .NET Web API : A controlled experiment conducted by integrating with the Swedish Companies Registration Office

Marjanovic, Rickard January 2022 (has links)
It is only a matter of time before the Swedish Companies Registration Office makes digital registration of annual reports/auditors reports mandatory. At the time of writing, there are only ten public integrators currently able to handle this requirement. In collaboration with one of the big four accounting firms, this project aims to evaluate performance of the response time while using GraphQL versus REST in Web APIs. The application under test is a .NET application integrating to the Swedish Companies Registration Office API. Through a controlled experiment using two different GraphQL frameworks, HotChocolate and GraphQL for .NET, this thesis provides a knowledge base for the partnered accounting firm, developers and other stakeholders that are evaluating the use of GraphQL in their future applications. Results  from the experiment indicate that HotChocolate in its current version is not only faster than its competitor GraphQL for .NET, but also faster than REST. This is surprising, given that other related work seems to suggest that this is not always the case. Testing of GraphQL for .NET gives a more traditional result when compared to other related work. Given the results, a senior developer of HotChocolate was contacted to gain insight to why the framework outperforms not only GraphQL for .NET but also REST. The senior developer states that a large amount of effort has been put in to make the GraphQL execution engine more optimized, something that is corroborated by this thesis experiment. HotChocolate is also periodically measuring and comparing performance benchmarks to other libraries to conclude on its performance in different scenarios. The analysis of the experiment concluded that there exists another important variable previously not identified in other research, more precisely the chosen framework, that has a large impact on performance and can impact both memory allocation and response time.
682

Geo-localization Refinement of Optical Satellite Images by Embedding Synthetic Aperture Radar Data in Novel Deep Learning Frameworks

Merkle, Nina Marie 06 December 2018 (has links)
Every year, the number of applications relying on information extracted from high-resolution satellite imagery increases. In particular, the combined use of different data sources is rising steadily, for example to create high-resolution maps, to detect changes over time or to conduct image classification. In order to correctly fuse information from multiple data sources, the utilized images have to be precisely geometrically registered and have to exhibit a high absolute geo-localization accuracy. Due to the image acquisition process, optical satellite images commonly have an absolute geo-localization accuracy in the order of meters or tens of meters only. On the other hand, images captured by the high-resolution synthetic aperture radar satellite TerraSAR-X can achieve an absolute geo-localization accuracy within a few decimeters and therefore represent a reliable source for absolute geo-localization accuracy improvement of optical data. The main objective of this thesis is to address the challenge of image matching between high resolution optical and synthetic aperture radar (SAR) satellite imagery in order to improve the absolute geo-localization accuracy of the optical images. The different imaging properties of optical and SAR data pose a substantial challenge for a precise and accurate image matching, in particular for the handcrafted feature extraction stage common for traditional optical and SAR image matching methods. Therefore, a concept is required which is carefully tailored to the characteristics of optical and SAR imagery and is able to learn the identification and extraction of relevant features. Inspired by recent breakthroughs in the training of neural networks through deep learning techniques and the subsequent developments for automatic feature extraction and matching methods of single sensor images, two novel optical and SAR image matching methods are developed. Both methods pursue the goal of generating accurate and precise tie points by matching optical and SAR image patches. The foundation of these frameworks is a semi-automatic matching area selection method creating an optimal initialization for the matching approaches, by limiting the geometric differences of optical and SAR image pairs. The idea of the first approach is to eliminate the radiometric differences between the images trough an image-to-image translation with the help of generative adversarial networks and to realize the subsequent image matching through traditional algorithms. The second approach is an end-to-end method in which a Siamese neural network learns to automatically create tie points between image pairs through a targeted training. The geo-localization accuracy improvement of optical images is ultimately achieved by adjusting the corresponding optical sensor model parameters through the generated set of tie points. The quality of the proposed methods is verified using an independent set of optical and SAR image pairs spread over Europe. Thereby, the focus is set on a quantitative and qualitative evaluation of the two tie point generation methods and their ability to generate reliable and accurate tie points. The results prove the potential of the developed concepts, but also reveal weaknesses such as the limited number of training and test data acquired by only one combination of optical and SAR sensor systems. Overall, the tie points generated by both deep learning-based concepts enable an absolute geo-localization improvement of optical images, outperforming state-of-the-art methods.
683

Recalage et analyse d’un couple d’images : application aux mammographies / Registration and analysis of a pair of images : application to mammography

Boucher, Arnaud 10 January 2013 (has links)
Dans le monde de la recherche, l’analyse du signal et plus particulièrement d’image, est un domaine très actif, de par la variété des applications existantes, avec des problématiques telles que la compression de données, la vidéo-surveillance ou encore l’analyse d’images médicales pour ne prendre que quelques exemples. Le mémoire s’inscrit dans ce dernier domaine particulièrement actif. Le nombre d’appareils d’acquisition existant ainsi que le nombre de clichés réalisés, entraînent la production d’une masse importante d’informations à traiter par les praticiens. Ces derniers peuvent aujourd’hui être assistés par l’outil informatique. Dans cette thèse, l’objectif est l’élaboration d’un système d’aide au diagnostic, fondé sur l’analyse conjointe, et donc la comparaison d’images médicales. Notre approche permet de détecter des évolutions, ou des tissus aberrants dans un ensemble donné, plutôt que de tenter de caractériser, avec un très fort a priori, le type de tissu cherché.Cette problématique permet d’appréhender un aspect de l’analyse du dossier médical d’un patient effectuée par les experts qui est l’étude d’un dossier à travers le suivi des évolutions. Cette tâche n’est pas aisée à automatiser. L’œil humain effectue quasi-automatiquement des traitements qu’il faut reproduire. Avant de comparer des régions présentes sur deux images, il faut déterminer où se situent ces zones dans les clichés. Toute comparaison automatisée de signaux nécessite une phase de recalage, un alignement des composantes présentes sur les clichés afin qu’elles occupent la même position sur les deux images. Cette opération ne permet pas, dans le cadre d’images médicales, d’obtenir un alignement parfait des tissus en tous points, elle ne peut que minimiser les écarts entre tissus. La projection d’une réalité 3D sur une image 2D entraîne des différences liées à l’orientation de la prise de vue, et ne permet pas d’analyser une paire de clichés par une simple différence entre images. Différentes structurations des clichés ainsi que différents champs de déformation sont ici élaborés afin de recaler les images de manière efficace.Après avoir minimisé les différences entre les positions sur les clichés, l’analyse de l’évolution des tissus n’est pas menée au niveau des pixels, mais à celui des tissus eux-mêmes, comme le ferait un praticien. Afin de traiter les clichés en suivant cette logique, les images numériques sont réinterprétées, non plus en pixels de différentes luminosités, mais en motifs représentatifs de l’ensemble de l’image, permettant une nouvelle décomposition des clichés, une décomposition parcimonieuse. L’atout d’une telle représentation est qu’elle permet de mettre en lumière un autre aspect du signal, et d’analyser sous un angle nouveau, les informations nécessaires à l’aide au diagnostic.Cette thèse a été effectuée au sein du laboratoire LIPADE de l’Université Paris Descartes (équipe SIP, spécialisée en analyse d’images) en collaboration avec la Société Fenics (concepteur de stations d’aide au diagnostic pour l’analyse de mammographies) dans le cadre d’un contrat Cifre. / In the scientific world, signal analysis and especially image analysis is a very active area, due to the variety of existing applications, with issues such as file compression, video surveillance or medical image analysis. This last area is particularly active. The number of existing devices and the number of pictures taken, cause the production of a large amount of information to be processed by practitioners. They can now be assisted by computers.In this thesis, the problem addressed is the development of a computer diagnostic aided system based on conjoint analysis, and therefore on the comparison of medical images. This approach allows to look for evolutions or aberrant tissues in a given set, rather than attempting to characterize, with a strong a priori, the type of fabric sought.This problem allows to apprehend an aspect of the analysis of medical file performed by experts which is the study of a case through the comparison of evolutions.This task is not easy to automate. The human eye performs quasi-automatically treatments that we need to replicate.Before comparing some region on the two images, we need to determine where this area is located on both pictures. Any automated comparison of signals requires a registration phase, an alignment of components present on the pictures, so that they occupy the same space on the two images. Although the characteristics of the processed images allow the development of a smart registration, the projection of a 3D reality onto a 2D image causes differences due to the orientation of the tissues observed, and will not allow to analyze a pair of shots with a simple difference between images. Different structuring of the pictures and different deformation fields are developed here to efficiently address the registration problem.After having minimized the differences on the pictures, the analysis of tissues evolution is not performed at pixels level, but the tissues themselves, as will an expert. To process the images in this logic, they will be reinterpreted, not as pixels of different brightness, but as patterns representative of the entire image, enabling a new decomposition of the pictures. The advantage of such a representation is that it allows to highlight another aspect of the signal, and analyze under a new perspective the information necessary to the diagnosis aid.This thesis has been carried out in the LIPADE laboratory of University Paris Descartes (SIP team, specialized in image analysis) and in collaboration with the Society Fenics (designer of diagnosis aid stations in the analysis of mammograms) under a Cifre convention. The convergence of the research fields of those teams led to the development of this document.
684

Komparace vybraných podacích deníků z let 1890-1950 / A Comparison of Selected Submission Diaries over 1890-1950

Kantorová, Alexandra January 2021 (has links)
This master's thesis, "A comparison of selected submission diaries from 1890 ̶1950," provides a detailed and complex analysis of selected submission diaries. The objective of this study is to compare selected submission diaries in various types of institutions. Furthermore, it examines how the given submission diaries changed over time within these institutions, who recorded this information, and what information was considered important in certain periods. The research is based on a study of archives from the following selected years: 1898, 1908, 1928, 1938 and 1948. In order to achieve the aim of this thesis, it was necessary to visit the National Archives in Prague, State Regional Archives in Prague, Prague City Archives, State County Archives in Beroun, Charles University Archives and National Museum archives. The study comprises a detailed internal and external analysis of the individual books. Interest is taken not only in changes on the surface, such as bent page corners, but the key concerns also include, for example, observations on the usage of official stamps in the individual books. Keywords Submission diary, submission protocol, book, institution, archive, essential registration needs
685

Convolutional Neural Network Optimization for Homography Estimation

DiMascio, Michelle Augustine January 2018 (has links)
No description available.
686

Ethical Leadership: Life Story of George Ciampa, U.S. WWII Military Veteran and Community Leader

Wiedemann, Susan M. 24 June 2020 (has links)
No description available.
687

Feature Extraction Based Iterative Closest Point Registration for Large Scale Aerial LiDAR Point Clouds

Graehling, Quinn R. January 2020 (has links)
No description available.
688

Development of statistical shape and intensity models of eroded scapulae to improve shoulder arthroplasty

Sharif Ahmadian, Azita 22 December 2021 (has links)
Reverse Total shoulder arthroplasty (RTSA) is an effective treatment and a surgical alternative approach to conventional total shoulder arthroplasty for patients with severe rotator cuff tears and glenoid erosion. To help optimize RTSA design, it is necessary to gain insight into the geometry of glenoid erosions and consider their unique morphology across the entire bone. One of the most powerful tools to systematically quantify and visualize the variation of bone geometry throughout a population is Statistical Shape Modeling (SSM); this method can assess the variation in the full shape of a bone, rather than of discrete anatomical features, which is very useful in identifying abnormalities, planning surgeries, and improving implant designs. Recently, many scapula SSMs have been presented in the literature; however, each has been created using normal and healthy bones. Therefore, creation of a scapula SSM derived exclusively from patients exhibiting complex glenoid bone erosions is critical and significantly challenging. In addition, several studies have quantified scapular bone properties in patients with complex glenoid erosion. However, because of their discrete nature these analyses cannot be used as the basis for Finite Element Modeling (FEM). Thus, a need exists to systematically quantify the variation of bone properties in a glenoid erosion patient population using a method that captures variation across the entire bone. This can be achieved using Statistical Intensity Modeling (SIM), which can then generate scapula FEMs with realistic bone properties for evaluation of orthopaedic implants. Using an SIM enables researchers to generate models with bone properties that represent a specific, known portion of the population variation, which makes the findings more generalizable. Accordingly, the main purpose of this research is to develop an SSM and SIM to mathematically quantifying the variation of bone geometries in a systematic manner for the complex geometry of scapulae with severe glenoid erosion and to determine the main modes of variation in bone property distribution, which could be used for future FEM studies, respectively. To draw meaningful statistical conclusions from the dataset, we need to compare and relate corresponding parts of the scapula. To achieve this correspondence, 3D triangulated mesh models of 61 scapulae were created from pre-operative CT scans from patients who were treated with RTSA and then a Non-Rigid (NR) registration method was used to morph one Atlas point cloud to the shapes of all other bones. However, the more complex the shape, the more difficult it is to maintain good correspondence. To overcome this challenge, we have adapted and optimized a NR-Iterative Closest Point (ICP) method and applied that on 61 eroded scapulae which results in each bone shape having identical mesh structure (i.e., same number and anatomical location of points). To assess the quality of our proposed algorithm, the resulting correspondence error was evaluated by comparing the positions of ground truth points and the corresponding point locations produced by the algorithm. The average correspondence error of all anatomical landmarks across the two observers was 2.74 mm with inter and intra-observer reliability of ±0.31 and ±0.06 mm. Moreover, the Root-Mean-Square (RMS) and Hausdorff errors of geometric registration between the original and the deformed models were calculated 0.25±0.04 mm and 0.76±0.14 mm, respectively. After registration, Principal Component Analysis (PCA) is applied to the deformed models as a group to describe independent modes of variation in the dataset. The robustness of the SSM is also evaluated using three standard metrics: compactness, generality, and specificity. Regarding compactness, the first 9 principal modes of variations accounted for 95% variability, while the model’s generality error and the calculated specificity over 10,000 instances were found to be 2.6 mm and 2.99 mm, respectively. The SIM results showed that the first mode of variation accounts for overall changes in intensity across the entire bone, while the second mode represented localized changes in the glenoid vault bone quality. The third mode showed changes in intensity at the posterior and inferior glenoid rim associated with posteroinferior glenoid rim erosion which suggests avoiding fixation in this region and preferentially placing screws in the anterosuperior region of the glenoid to improve implant fixation. / Graduate
689

Automatic Registration of Optical Aerial Imagery to a LiDAR Point Cloud for Generation of Large Scale City Models

Abayowa, Bernard Olushola 30 August 2013 (has links)
No description available.
690

Scanning Laser Registration and Structural Energy Density Based Active Structural Acoustic Control

Manwill, Daniel Alan 17 December 2010 (has links) (PDF)
To simplify the measurement of energy-based structural metrics, a general registration process for the scanning laser doppler vibrometer (SLDV) has been developed. Existing registration techniques, also known as pose estimation or position registration, suffer from mathematical complexity, instrument specificity, and the need for correct optimization initialization. These difficulties have been addressed through development of a general linear laser model and hybrid registration algorithm. These are applicable to any SLDV and allow the registration problem to be solved using straightforward mathematics. Additionally, the hybrid registration algorithm eliminates the need for correct optimization initialization by separating the optimization process from solution selection. The effectiveness of this approach is demonstrated through simulated application and by validation measurements performed on a specially prepared pipe. To increase understanding of the relationships between structural energy metrics and the acoustic response, the use of structural energy density (SED) in active structural acoustic control (ASAC) has also been studied. A genetic algorithm and other simulations were used to determine achievable reduction in acoustic radiation, characterize control system design, and compare SED-based control with the simpler velocity-based control. Using optimized sensor and actuator placements at optimally excited modal frequencies, attenuation of net acoustic intensity was proportional to attenuation of SED. At modal and non-modal frequencies, optimal SED-based ASAC system design is guided by establishing general symmetry between the structural disturbing force and the SED sensor and control actuator. Using fixed sensor and actuator placement, SED-based control has been found to provide superior performance to single point velocity control and very comparable performance to two-point velocity control. Its greatest strength is that it rarely causes unwanted amplifications of large amplitude when properly designed. Genetic algorithm simulations of SED-based ASAC indicated that optimal control effectiveness is obtained when sensors and actuators function in more than one role. For example, an actuator can be placed to simultaneously reduce structural vibration amplitude and reshape the response such that it radiates less efficiently. These principles can be applied to the design of any type of ASAC system.

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