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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.
561

JOHN MACKEY’S WINE-DARK SEA: SYMPHONY FOR BAND A DISCOURSE AND ANALYSIS OF JOHN MACKEY’S SYMPHONY FOR BAND

Sweet, Jonathan C. 01 January 2019 (has links)
John Mackey’s Wine-Dark Sea: Symphony for Band(2014) is a work of epic proportions and was the winner of the William D. Revelli Composition Contest of the National Band Association in 2015. Wine-Dark Sea: Symphony for Bandhas received much acclaim and many performances including a recording by the University of Texas Wind Ensemble in 2016. The purposes of this dissertation are 1) to provide historical information on the genesis of the work through interviews with its composer, John Mackey, and commissioning director, Jerry Junkin; 2) to provide an analysis of how the programmatic elements of Homer’s Odysseyinteract with the musical aspects of the work. The first chapter discusses biographical information essential to the understanding of John Mackey’s music. Chapter two includes information specific to the creation of Wine-Dark Sea: Symphony for Band. Chapters three through five provide analytical information alongside programmatic information to provide a clear understanding of how the music and programmatic elements combine to create the work. Chapter six concludes the document with some performance suggestions for the conductor. An appendix of information including graphs of how dynamic range corresponds to programmatic elements and interviews with the composer, John Mackey, and the commissioner, Jerry Junkin, are also provided.
562

Observation adaptative : limites de la prévision et du contrôle des incertitudes / Adaptive Observation : limits of the forecast and monitoring of the uncertainties

Oger, Niels 02 July 2015 (has links)
L'observation adaptative (OA) est une pratique de prévision numérique du temps (PNT) qui cherche à prévoir quel jeu (ou réseau) d'observations supplémentaires à déployer et à assimiler dans le futur améliorera les prévisions. L'objectif est d'accroître la qualité des prévisions météorologiques en ajoutant des observations là où elles auront le meilleur impact (optimal). Des méthodes numériques d'OA apportent des réponses objectives mais partielles. Elles prennent en compte à la fois les aspects dynamiques de l'atmosphère à travers le modèle adjoint, et aussi le système d'assimilation de données. Le système d'assimilation de données le plus couramment utilisé pour l'OA est le 4D-Var. Ces méthodes linéaires (technologie de l'adjoint) reposent cependant sur une réalisation déterministe (ou trajectoire) unique. Cette trajectoire est entachée d'une incertitude qui affecte l'efficacité de l'OA. Le point de départ de ce travail est d'évaluer l'impact de l'incertitude associée au choix de cette trajectoire sur une technique: la KFS. Un ensemble de prévisions est utilisé pour étudier cette sensibilité. Les expériences réalisées dans un cadre simplifié montrent que les solutions de déploiement peuvent changer en fonction de la trajectoire choisie. Il est d'autant plus nécessaire de prendre cette incertitude en considération que le système d'assimilation utilisé n'est pas vraiment optimal du fait de simplifications liées à sa mise en oeuvre. Une nouvelle méthode d'observation adaptative, appelée Variance Reduction Field (VRF), a été développée dans le cadre de cette thèse. Cette méthode permet de déterminer la réduction de variance de la fonction score attendue en assimilant une pseudo-observation supplémentaire pour chaque point de grille. Deux approches de la VRF sont proposées, la première est basée sur une simulation déterministe. Et la seconde utilise un ensemble d'assimilations et de prévisions. Les deux approches de la VRF ont été implémentées et étudiées dans le modèle de Lorenz 96. Le calcul de la VRF à partir d'un ensemble est direct si l'on dispose déjà des membres de l'ensemble. Le modèle adjoint n'est pas nécessaire pour le calcul.L'implémentation de la VRF dans un système de prévision du temps de grande taille, tel qu'un système opérationnel, n'a pas pu être réalisée dans le cadre de cette thèse. Cependant, l'étude de faisabilité de la construction de la VRF dans l'environnement OOPS a été menée. Une description de OOPS (version 2013) est d'abord présentée dans le manuscrit, car cet environnement est une nouveauté en soi. Elle est suivie de la réflexion sur les développements à introduire pour l'implémentation de la VRF. / The purpose of adaptive observation (AO) strategies is to design optimal observation networks in a prognostic way to provide guidance on how to deploy future observations. The overarching objective is to improve forecast skill. Most techniques focus on adding observations. Some AO techniques account for the dynamical aspects of the atmosphere using the adjoint model and for the data assimilation system (DAS), which is usually either a 3D or 4D-Var (ie. solved by the minimization of a cost function). But these techniques rely on a single (linearisation) trajectory. One issue is to estimate how the uncertainty related to the trajectory affects the efficiency of one technique in particular: the KFS. An ensemble-based approach is used to assess the sensitivity to the trajectory within this deterministic approach (ie. with the adjoint model). Experiments in a toy model show that the trajectory uncertainties can lead to significantly differing deployments of observations when using a deterministic AO method (with adjoint model and VDAS). This is especially true when we lack knowledge on the VDAS component. During this work a new tool for observation targeting called Variance Reduction Field (VRF)has been developed. This technique computes the expected variance reduction of a forecast Score function that quantifies forecast quality. The increase of forecast quality that is a reduction of variance of that function is linked to the location of an assimilated test probe. Each model grid point is tested as a potential location. The VRF has been implemented in a Lorenz 96 model using two approaches. The first one is based on a deterministic simulation. The second approach consists of using an ensemble data assimilation and prediction system. The ensemble approach can be easily implemented when we already have an assimilation ensemble and a forecast ensemble. It does not need the use of the adjoint model. The implementation in real NWP system of the VRF has not been conducted during this work. However a preliminary study has been done to implement the VRF within OOPS (2013 version). After a description of the different components of OOPS, the elements required for the implementation of the VRF are described.
563

Making Music with a guitar orchestra : Motivation and friendship

Casallas Fernandez, Jose Andres January 2019 (has links)
How can I, as a leader, keep the motivation of the participants in a group?   When I started to write this report, I was focused on, how a group could affect the participants motivation of the participants, but little by little I realized that the biggest motivation came from that this group affected mostly my own motivationmyself. The guitar orchestra has given me the opportunity to learn and it has given another sense to my knowledge as musician and teacher. Analysing what I have done with the guitar orchestra has awakened more questions than answers. What exactly did I do? Why did I do it? Was it really effective?   This written part of my project at KMH describes how, together with my colleagues, we have organized an orchestra of guitars in Avonia music institute based in Espoo, Finland and how this group and my own motivation have affected the motivation of the participants. / Making Music with a guitar orchestra
564

Learning to Predict Clinical Outcomes from Soft Tissue Sarcoma MRI

Farhidzadeh, Hamidreza 06 November 2017 (has links)
Soft Tissue Sarcomas (STS) are among the most dangerous diseases, with a 50% mortality rate in the USA in 2016. Heterogeneous responses to the treatments of the same sub-type of STS as well as intra-tumor heterogeneity make the study of biopsies imprecise. Radiologists make efforts to find non-invasive approaches to gather useful and important information regarding characteristics and behaviors of STS tumors, such as aggressiveness and recurrence. Quantitative image analysis is an approach to integrate information extracted using data science, such as data mining and machine learning with biological an clinical data to assist radiologists in making the best recommendation on clinical trials and the course of treatment. The new methods in “Radiomics" extract meaningful features from medical imaging data for diagnostic and prognostic goals. Furthermore, features extracted from Convolutional Neural Networks (CNNs) are demonstrating very powerful and robust performance in computer aided decision systems (CADs). Also, a well-known computer vision approach, Bag of Visual Words, has recently been applied on imaging data for machine learning purposes such as classification of different types of tumors based on their specific behavior and phenotype. These approaches are not fully and widely investigated in STS. This dissertation provides novel versions of image analysis based on Radiomics and Bag of Visual Words integrated with deep features to quantify the heterogeneity of entire STS as well as sub-regions, which have predictive and prognostic imaging features, from single and multi-sequence Magnetic Resonance Imaging (MRI). STS are types of cancer which are rarely touched in term of quantitative cancer analysis versus other type of cancers such as lung, brain and breast cancers. This dissertation does a comprehensive analysis on available data in 2D and multi-slice to predict the behavior of the STS with regard to clinical outcomes such as recurrence or metastasis and amount of tumor necrosis. The experimental results using Radiomics as well as a new ensemble of Bags of Visual Words framework are promising with 91.66% classification accuracy and 0.91 AUC for metastasis, using ensemble of Bags of Visual Words framework integrated with deep features, and 82.44% classification accuracy with 0.63 AUC for necrosis progression, using Radiomics framework, in tests on the available datasets.
565

Machine learning for automatic classification of remotely sensed data

Milne, Linda, Computer Science & Engineering, Faculty of Engineering, UNSW January 2008 (has links)
As more and more remotely sensed data becomes available it is becoming increasingly harder to analyse it with the more traditional labour intensive, manual methods. The commonly used techniques, that involve expert evaluation, are widely acknowledged as providing inconsistent results, at best. We need more general techniques that can adapt to a given situation and that incorporate the strengths of the traditional methods, human operators and new technologies. The difficulty in interpreting remotely sensed data is that often only a small amount of data is available for classification. It can be noisy, incomplete or contain irrelevant information. Given that the training data may be limited we demonstrate a variety of techniques for highlighting information in the available data and how to select the most relevant information for a given classification task. We show that more consistent results between the training data and an entire image can be obtained, and how misclassification errors can be reduced. Specifically, a new technique for attribute selection in neural networks is demonstrated. Machine learning techniques, in particular, provide us with a means of automating classification using training data from a variety of data sources, including remotely sensed data and expert knowledge. A classification framework is presented in this thesis that can be used with any classifier and any available data. While this was developed in the context of vegetation mapping from remotely sensed data using machine learning classifiers, it is a general technique that can be applied to any domain. The emphasis of the applicability for this framework being domains that have inadequate training data available.
566

Effective Linear-Time Feature Selection

Pradhananga, Nripendra January 2007 (has links)
The classification learning task requires selection of a subset of features to represent patterns to be classified. This is because the performance of the classifier and the cost of classification are sensitive to the choice of the features used to construct the classifier. Exhaustive search is impractical since it searches every possible combination of features. The runtime of heuristic and random searches are better but the problem still persists when dealing with high-dimensional datasets. We investigate a heuristic, forward, wrapper-based approach, called Linear Sequential Selection, which limits the search space at each iteration of the feature selection process. We introduce randomization in the search space. The algorithm is called Randomized Linear Sequential Selection. Our experiments demonstrate that both methods are faster, find smaller subsets and can even increase the classification accuracy. We also explore the idea of ensemble learning. We have proposed two ensemble creation methods, Feature Selection Ensemble and Random Feature Ensemble. Both methods apply a feature selection algorithm to create individual classifiers of the ensemble. Our experiments have shown that both methods work well with high-dimensional data.
567

An approach to boosting from positive-only data

Mitchell, Andrew, Computer Science & Engineering, Faculty of Engineering, UNSW January 2004 (has links)
Ensemble techniques have recently been used to enhance the performance of machine learning methods. However, current ensemble techniques for classification require both positive and negative data to produce a result that is both meaningful and useful. Negative data is, however, sometimes difficult, expensive or impossible to access. In this thesis a learning framework is described that has a very close relationship to boosting. Within this framework a method is described which bears remarkable similarities to boosting stumps and that does not rely on negative examples. This is surprising since learning from positive-only data has traditionally been difficult. An empirical methodology is described and deployed for testing positive-only learning systems using commonly available multiclass datasets to compare these learning systems with each other and with multiclass learning systems. Empirical results show that our positive-only boosting-like method learns, using stumps as a base learner and from positive data only, successfully, and in the process does not pay too heavy a price in accuracy compared to learners that have access to both positive and negative data. We also describe methods of using positive-only learners on multiclass learning tasks and vice versa and empirically demonstrate the superiority of our method of learning in a boosting-like fashion from positive-only data over a traditional multiclass learner converted to learn from positive-only data. Finally we examine some alternative frameworks, such as when additional unlabelled training examples are given. Some theoretical justifications of the results and methods are also provided.
568

台股指數交易之研究 – EEMD與ANN方法 / Taiwan weighted stock index trading research-EEMD And ANN method

蔡橙檥 Unknown Date (has links)
在台灣證券市場中,有許多的技術分析方法或指標,市場參與者或財 務學者會利用歷史資料來做回溯測試,找出可運用的方法或指標,以此來 推測出台股加權指數未來的趨勢,也有學者利用類神經網路(Artificial Neural Network, ANN)考慮經濟景氣、技術分析指標等作為輸入變數來預測 台股加權指數,而本文則利用 EEMD(Ensemble Empirical Mode Decomposition)拆解出來的結果作為 ANN 的輸入變數,並將 ANN 預測出 的值轉換成 FK (Forward-calculated %K) 值,再搭配不同的交易方式,來 補捉台股加權指數的走勢,並比較各種交易方式的績效,找出一個能夠穩 定獲利的交易模型。
569

Recherche de similarités dans les séquences d'ADN : modèles et algorithmes pour la conception de graines efficaces

Noé, Laurent 30 September 2005 (has links) (PDF)
Les méthodes de recherche de similarités les plus fréquemment utilisées dans le cadre de la génomique sont heuristiques.<br />Elles se basent sur un principe de filtrage du texte qui permet de localiser les régions potentiellement similaires.<br />Dans cette thèse, nous proposons de nouvelles définitions de filtres pour la recherche de similarités sur les séquences génomiques et des algorithmes associés pour mesurer leurs caractéristiques.<br /> Plus précisément, nous avons étudié le modèle des graines espacées, et proposé un algorithme d'évaluation de l'efficacité des graines sur des similarités d'une classe particulière (similarités dites homogènes). Nous avons également développé un algorithme général pour la mesure de l'efficacité des graines, ainsi qu'un nouveau modèle de graine appelé graine sous-ensemble, extension du modèle des graines espacées. Enfin nous donnons, dans le cadre du filtrage sans perte, une extension à l'aide de graines multiples, que nous analysons et appliquons au problème de la conception d'oligonucléotides.<br /> Nous avons réalisé et donnons accès à des outils pour la conception des filtres, ainsi que pour la recherche de similarités.
570

Sur l'utilisation active de la diversité dans la construction d'ensembles de classifieurs. Application à la détection de fumées nocives sur site industriel

Gacquer, David 05 December 2008 (has links) (PDF)
L'influence de la diversité lors de la construction d'ensembles de classifieurs a soulevé de nombreuses discussions au sein de la communauté de l'Apprentissage Automatique ces dernières années. <br> Une manière particulière de construire un ensemble de classifieurs consiste à sélectionner individuellement les membres de l'ensemble à partir d'un pool de classifieurs en se basant sur des critères prédéfinis. <br> La littérature fait référence à cette méthode sous le terme de paradigme Surproduction et Sélection, également appelé élagage d'ensemble de classifieurs.<br> <br> Les travaux présentés dans cette thèse ont pour objectif d'étudier le compromis entre la précision et la diversité existant dans les ensembles de classifieurs. Nous apportons également certains éléments de réponse sur le comportement insaisissable de la diversité lorsqu'elle est utilisée de manière explicite lors de la construction d'un ensemble de classifieurs.<br> <br> Nous commençons par étudier différents algorithmes d'apprentissage de la littérature. Nous présentons également les algorithmes ensemblistes les plus fréquemment utilisés. Nous définissons ensuite le concept de diversité dans les ensembles de classifieurs ainsi que les différentes méthodes permettant de l'utiliser directement lors de la création de l'ensemble.<br> <br> Nous proposons un algorithme génétique permettant de construire un ensemble de classifieurs en contrôlant le compromis entre précision et diversité lors de la sélection des membres de l'ensemble. Nous comparons notre algorithme avec différentes heuristiques de sélection proposées dans la littérature pour construire un ensemble de classifieurs selon le paradigme Surproduction et Sélection.<br> <br> Les différentes conclusions que nous tirons des résultats obtenus pour différents jeux de données de l'UCI Repository nous conduisent à la proposition de conditions spécifiques pour lesquelles l'utilisation de la diversité peut amener à une amélioration des performances de l'ensemble de classifieurs. Nous montrons également que l'efficacité de l'approche Surproduction et Sélection repose en grande partie sur la stabilité inhérente au problème posé.<br> <br> Nous appliquons finalement nos travaux de recherche au développement d'un système de classification supervisée pour le contrôle de la pollution atmosphérique survenant sur des sites industriels. Ce système est basé sur l'analyse par traitement d'image de scènes à risque enregistrées à l'aide de caméras. Son principal objectif principal est de détecter les rejets de fumées dangereux émis par des usines sidérurgiques et pétro-chimiques.

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