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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.
81

Modeling and Design of Antennas for Loosely Coupled Links in Wireless Power Transfer Applications

Sinclair, Melissa Ann 08 1900 (has links)
Wireless power transfer (WPT) systems are important in many areas, such as medical, communication, transportation, and consumer electronics. The underlying WPT system is comprised of a transmitter (TX) and receiver (RX). For biomedical applications, such systems can be implemented on rigid or flexible substrates and can be implanted or wearable. The efficiency of a WPT system is based on power transfer efficiency (PTE). Many WPT system optimization techniques have been explored to achieve the highest PTE possible. These are based on either a figure-of-merit (FOM) approach, quality factor (Q-factor) maximization, or by sweeping values for coil geometries. Four WPT systems for biomedical applications are implemented with inductive coupling. The thesis later presents an optimization technique for finding the maximum PTE of a range of frequencies and coil shapes through frequency, geometry and shape sweeping. Five optimized TX coil designs for different operating frequencies are fabricated for three shapes: square, hexagonal, and octagonal planar-spirals. The corresponding RX is implemented on polyimide tape with ink-jet-print (IJP) silver. At 80 MHz, the maximum measured PTE achieved is 2.781% at a 10 mm distance in the air for square planar-spiral coils.
82

Étude comparative d'efficience d'approches pédagogiques inductive et déductive pour l'enseignement de la grammaire en 1re secondaire : le cas du complément du nom

Vincent, François January 2014 (has links)
Résumé : Au Québec, la situation en termes d’apprentissage des savoirs grammaticaux, et surtout de mobilisation de ces derniers en situation d’écriture, est inquiétante. Pour rendre son intervention plus efficiente, l'enseignant peut choisir une approche pédagogique déductive (explication d'un concept suivi d'exercices) ou inductive (observation d'exemples avant la vérification d'hypothèse et les exercices). Notre objectif principal est d'évaluer les incidences d’une intervention éducative en grammaire selon des approches pédagogiques inductive ou déductive sur l’apprentissage par des élèves de 1re secondaire du complément du nom et son impact dans le développement de la compétence savoir écrire. Notre objet d’enseignement, le complément du nom (CN) est un concept de la grammaire actuelle, dont les caractéristiques facilitent son utilisation réfléchie en rédaction, surtout lors des phases de révision et de réécriture. Une méthodologie mixte de recherche a permis de recueillir des données auprès d'un échantillon de 269 élèves de première secondaire, de même qu’auprès de trois enseignants. Pour cette recherche exploratoire d’épistémologie pragmatique, nous avons réalisé des tests de connaissances, des analyses de rédactions et des entrevues auprès d’élèves et d'enseignants. Les résultats obtenus aux tests de connaissances nous montrent qu’il n’y a pas d’écart significatif entre l’amélioration des élèves ayant vécu l’approche inductive et ceux ayant vécu l’approche déductive, si ce n’est d’un léger avantage en ce qui concerne les accords pour les élèves ayant vécu l’approche déductive. Ce qui a par contre émergé de cette expérimentation est d’une part l’effet évident de l’apprentissage des CN sur leurs mobilisations en écriture, peu importe l’approche. D’autre part, les élèves ayant eu une forte amélioration ont confirmé que pour une approche ou une autre, leur implication cognitive demeure l’élément fondamental de l’efficacité de l’intervention éducative. Nous pouvons donc conclure qu’une approche n’est pas significativement supérieure à l’autre dans le cadre de l’enseignement des CN, mais que l’enseignant doit adapter son approche à la situation en tenant compte du contexte, des apprenants et des aspects de l'objet concernés. // Abstract : The choice of an educational approach by a teacher is a significant factor on student achievement. In Quebec, the situation in terms of apprentissage of grammatical knowledge, and especially using that knowledge in writing situations, is worrying. The success rate for the ministerial writing tests graze 60 %. One possible taxonomies to distinguish pedagogical approaches to teaching grammar lies between the inductive and deductive approaches. Our project has for main objective to assess the impact of an educational intervention according to inductive or deductive teaching approaches on learning, by high school students, of a grammar concept (complément du nom) and its impact on the development of writing competencies. In research, if the deductive approach always results, by the teacher explaining a concept, and the students practicing and being evaluated, the inductive approach is defined differently by the authors. For methodological considerations, and because it's a school tradition, we chose to consider an explicit approach focused on the discovery rather than a more implicit approach. Our teaching object, the « complément du nom » (CN) is a concept of the current grammar, including morphological, semantic and syntactic features, should facilitate thoughtful use for writing, especially during phases of revision and rewriting. For all these reasons, this(?) teaching is relevant of a competency-based program, especially since most of the concept notions are provided in Secondary 1 program by the « Progression des apprentissages » (MELS, 2010). A mixed research methodology was used to collect data from a sample of 269 students from eight classes of Secondary 1 , and of three French teachers. For this exploratory research, we used knowledge tests , reviews process marks by the students on writing productions, and interviews with students and teachers in order to document the impact of the teaching sequences, in terms of knowledge learning and 7 mobilization in writing productions. The comparative approach we used allowed us to assess the extent and nature of learning, according to our independent variable (the deductive and inductive teaching approaches), but also on the interrelation between this variable and other aspects of the educational intervention. The test of knowledge scores show that there is no significant difference between the improvement of students who lived an inductive approach and those who lived the deductive approach, except a slight advantage as regards as morphological characteristics for students who lived the deductive approach. What has emerged in this experiment is firstly the obvious effect of learning on their CN mobilizations in writing, regardless of the approach. On the other hand, students who had a strong improvement confirmed that with an approach or another, their cognitive involvement are fundamental to the effectiveness of the educational intervention. Finally, the quasi-experimental context has limited professional actions of the teachers, and at the same time limited their ability to adapt teaching situations. Those who chose to take certain liberties with the scenarios provided, by professional considerations, are those who have seen the results of their students rise, and that, regardless of the pedagogical approach. We can therefore conclude that an approach was not significantly superior to another for teaching of CN in High school, but the teacher must adapt his approach to the situation, taking into account the context, the learners and the aspects of the learning object.
83

Tree Transformations in Inductive Dependency Parsing

Nilsson, Jens January 2007 (has links)
<p>This licentiate thesis deals with automatic syntactic analysis, or parsing, of natural languages. A parser constructs the syntactic analysis, which it learns by looking at correctly analyzed sentences, known as training data. The general topic concerns manipulations of the training data in order to improve the parsing accuracy.</p><p>Several studies using constituency-based theories for natural languages in such automatic and data-driven syntactic parsing have shown that training data, annotated according to a linguistic theory, often needs to be adapted in various ways in order to achieve an adequate, automatic analysis. A linguistically sound constituent structure is not necessarily well-suited for learning and parsing using existing data-driven methods. Modifications to the constituency-based trees in the training data, and corresponding modifications to the parser output, have successfully been applied to increase the parser accuracy. The topic of this thesis is to investigate whether similar modifications in the form of tree transformations to training data, annotated with dependency-based structures, can improve accuracy for data-driven dependency parsers. In order to do this, two types of tree transformations are in focus in this thesis.</p><p>%This is a topic that so far has been less studied.</p><p>The first one concerns non-projectivity. The full potential of dependency parsing can only be realized if non-projective constructions are allowed, which pose a problem for projective dependency parsers. On the other hand, non-projective parsers tend, among other things, to be slower. In order to maintain the benefits of projective parsing, a tree transformation technique to recover non-projectivity while using a projective parser is presented here.</p><p>The second type of transformation concerns linguistic phenomena that are possible but hard for a parser to learn, given a certain choice of dependency analysis. This study has concentrated on two such phenomena, coordination and verb groups, for which tree transformations are applied in order to improve parsing accuracy, in case the original structure does not coincide with a structure that is easy to learn.</p><p>Empirical evaluations are performed using treebank data from various languages, and using more than one dependency parser. The results show that the benefit of these tree transformations used in preprocessing and postprocessing to a large extent is language, treebank and parser independent.</p>
84

Tree Transformations in Inductive Dependency Parsing

Nilsson, Jens January 2007 (has links)
<p>This licentiate thesis deals with automatic syntactic analysis, or parsing, of natural languages. A parser constructs the syntactic analysis, which it learns by looking at correctly analyzed sentences, known as training data. The general topic concerns manipulations of the training data in order to improve the parsing accuracy.</p><p>Several studies using constituency-based theories for natural languages in such automatic and data-driven syntactic parsing have shown that training data, annotated according to a linguistic theory, often needs to be adapted in various ways in order to achieve an adequate, automatic analysis. A linguistically sound constituent structure is not necessarily well-suited for learning and parsing using existing data-driven methods. Modifications to the constituency-based trees in the training data, and corresponding modifications to the parser output, have successfully been applied to increase the parser accuracy. The topic of this thesis is to investigate whether similar modifications in the form of tree transformations to training data, annotated with dependency-based structures, can improve accuracy for data-driven dependency parsers. In order to do this, two types of tree transformations are in focus in this thesis.</p><p>The first one concerns non-projectivity. The full potential of dependency parsing can only be realized if non-projective constructions are allowed, which pose a problem for projective dependency parsers. On the other hand, non-projective parsers tend, among other things, to be slower. In order to maintain the benefits of projective parsing, a tree transformation technique to recover non-projectivity while using a projective parser is presented here.</p><p>The second type of transformation concerns linguistic phenomena that are possible but hard for a parser to learn, given a certain choice of dependency analysis. This study has concentrated on two such phenomena, coordination and verb groups, for which tree transformations are applied in order to improve parsing accuracy, in case the original structure does not coincide with a structure that is easy to learn.</p><p>Empirical evaluations are performed using treebank data from various languages, and using more than one dependency parser. The results show that the benefit of these tree transformations used in preprocessing and postprocessing to a large extent is language, treebank and parser independent.</p>
85

An inductive logic programming approach to learning which uORFs regulate gene expression

Selpi January 2008 (has links)
Some upstream open reading frames (uORFs) regulate gene expression (i.e. they are functional) and can play key roles in keeping organisms healthy. However, how uORFs are involved in gene regulation is not het fully understood. In order to get a complete view of how uORFs are involved in gene regulation, it is expected that a large number of functional uORFs are needed. Unfortunately , lab experiments to verify that uORFs are functional are expensive. In this thesis, for the first time, the use of inductive logic programming (ILP) is explored for the task of learning which uORFs regulate gene expression in the yeast Saccharomyces cerevisiae. This work is directed to help select sets of candidate functional uORFs for experimental studies. With limited background knowledge, ILP can generate hypotheses which make the search for novel functional uORFs 17 times more efficient than random sampling. Adding mRNA secondary structure to the background knowledge results in hypotheses with significantly increased performance. This work is the first machine learning work to study both uORFs and mRNA secondary structures in the context of gene regulation. Using a novel combination of knowledge about biological conservation, gene ontology annotations and genes' response to different conditions results in hypotheses that are simple, informative, have an estimated sensitivity of 81% and provide provisional insights into biological characteristics of functional uORFs. The hypotheses predict 299 further genes to have 450 novel functional uORFs. A comparison with a related study suggests that 8 of these predicted functional uORFs (from 8 genes) are strong candidates for experimental studies.
86

Vid den cancersjukes sida   Närståendes upplevelse av egen hälsa / To live next to a person with cancer. Related partners experiences of their own health

Englund, Sofia, Eklind, Sandra January 2017 (has links)
No description available.
87

The Relative Effectiveness of the Inductive-Deductive and the Deductive-Descriptive Methods in the Teaching of College Zoology

Craik, Eva Lee, 1919- 08 1900 (has links)
This study was concerned with making a comparative analysis of the relative effectiveness of two teaching methods in increasing students' (a) knowledge and understanding of principles, (b) ability in critical thinking, and (c) science reasoning and understanding in an introductory college zoology course. The two methods were (a) a laboratory-centered inductive-deductive method and (b) the more commonly found deductive-descriptive method organized as a large lecture section with smaller laboratory sections.
88

Practical Parallel Processing

Zhang, Hua, 1954- 08 1900 (has links)
The physical limitations of uniprocessors and the real-time requirements of numerous practical applications have made parallel processing an essential technology in military, industry and scientific research. In this dissertation, we investigate parallelizations of three practical applications using three parallel machine models. The algorithms are: Finitely inductive (FI) sequence processing is a pattern recognition technique used in many fields. We first propose four parallel FI algorithms on the EREW PRAM. The time complexity of the parallel factoring and following by bucket packing is O(sk^2 n/p), and they are optimal under some conditions. The parallel factoring and following by hashing requires O(sk^2 n/p) time when uniform hash functions are used and log(p) ≤ k n/p and pm ≈ n. Their speedup is proportional to the number processors used. For these results, s is the number of levels, k is the size of the antecedents and n is the length of the input sequence and p is the number of processors. We also describe algorithms for raster/vector conversion based on the scan model to handle block-like connected components of arbitrary geometrical shapes with multi-level nested dough nuts for the IES (image exploitation system). Both the parallel raster-to-vector algorithm and parallel vector-to-raster algorithm require O(log(n2)) or O(log2(n2)) time (depending on the sorting algorithms used) for images of size n2 using p = n2 processors. Not only is the DWT (discrete wavelet transforms) useful in data compression, but also has it potentials in signal processing, image processing, and graphics. Therefore, it is of great importance to investigate efficient parallelizations of the wavelet transforms. The time complexity of the parallel forward DWT on the parallel virtual machine with linear processor organization is O(((so+s1)mn)/p), where s0 and s1 are the lengths of the filters and p is the number of processors used. The time complexity of the inverse DWT is also O(((so+s1)mn)/p). If the processors are organized as a 2D array with PrawPcol processors, both the interleaved parallel DWT and IDWT have the time complexity of O(((so+s1)mn)/ProwPcol). We have parallelized three applications and achieved optimality or best-possible performances for each of the three applications over each of the chosen machine models. Future research will involve continued examination of parallel architectures for implementation of practical problems.
89

A Comparison of an Inductive and a Deductive Procedure of Teaching in a College Mathematics Course for Prospective Elementary Teachers

Morris, James Kent 12 1900 (has links)
To obtain information regarding the effects of two divergent thought processes used in a college mathematics course for prospective elementary school teachers, this study compared the effectiveness of an adaptation of the traditional, deductive teaching method with that of an inductive method reflecting the recommendations of the Committee on the Undergraduate Program in Mathematics. In the spring semester of 1973, two sections of Mathematics for Elementary Teachers I, at Cameron College, Lawton, Oklahoma, served as experimental groups to test the two adaptations. The course followed the Committee on the Undergraduate Program in Mathematics recommendations for a first course in mathematics for prospective elementary teachers.
90

Transfer Learning for Image Classification / Transfert de connaissances pour la classification des images -

Lu, Ying 09 November 2017 (has links)
Lors de l’apprentissage d’un modèle de classification pour un nouveau domaine cible avec seulement une petite quantité d’échantillons de formation, l’application des algorithmes d’apprentissage automatiques conduit généralement à des classifieurs surdimensionnés avec de mauvaises compétences de généralisation. D’autre part, recueillir un nombre suffisant d’échantillons de formation étiquetés manuellement peut s’avérer très coûteux. Les méthodes de transfert d’apprentissage visent à résoudre ce type de problèmes en transférant des connaissances provenant d’un domaine source associé qui contient beaucoup plus de données pour faciliter la classification dans le domaine cible. Selon les différentes hypothèses sur le domaine cible et le domaine source, l’apprentissage par transfert peut être classé en trois catégories: apprentissage par transfert inductif, apprentissage par transfert transducteur (adaptation du domaine) et apprentissage par transfert non surveillé. Nous nous concentrons sur le premier qui suppose que la tâche cible et la tâche source sont différentes mais liées. Plus précisément, nous supposons que la tâche cible et la tâche source sont des tâches de classification, tandis que les catégories cible et les catégories source sont différentes mais liées. Nous proposons deux méthodes différentes pour aborder ce problème. Dans le premier travail, nous proposons une nouvelle méthode d’apprentissage par transfert discriminatif, à savoir DTL(Discriminative Transfer Learning), combinant une série d’hypothèses faites à la fois par le modèle appris avec les échantillons de cible et les modèles supplémentaires appris avec des échantillons des catégories sources. Plus précisément, nous utilisons le résidu de reconstruction creuse comme discriminant de base et améliore son pouvoir discriminatif en comparant deux résidus d’un dictionnaire positif et d’un dictionnaire négatif. Sur cette base, nous utilisons des similitudes et des dissemblances en choisissant des catégories sources positivement corrélées et négativement corrélées pour former des dictionnaires supplémentaires. Une nouvelle fonction de coût basée sur la statistique de Wilcoxon-Mann-Whitney est proposée pour choisir les dictionnaires supplémentaires avec des données non équilibrées. En outre, deux processus de Boosting parallèles sont appliqués à la fois aux distributions de données positives et négatives pour améliorer encore les performances du classificateur. Sur deux bases de données de classification d’images différentes, la DTL proposée surpasse de manière constante les autres méthodes de l’état de l’art du transfert de connaissances, tout en maintenant un temps d’exécution très efficace. Dans le deuxième travail, nous combinons le pouvoir du transport optimal (OT) et des réseaux de neurones profond (DNN) pour résoudre le problème ITL. Plus précisément, nous proposons une nouvelle méthode pour affiner conjointement un réseau de neurones avec des données source et des données cibles. En ajoutant une fonction de perte du transfert optimal (OT loss) entre les prédictions du classificateur source et cible comme une contrainte sur le classificateur source, le réseau JTLN (Joint Transfer Learning Network) proposé peut effectivement apprendre des connaissances utiles pour la classification cible à partir des données source. En outre, en utilisant différents métriques comme matrice de coût pour la fonction de perte du transfert optimal, JTLN peut intégrer différentes connaissances antérieures sur la relation entre les catégories cibles et les catégories sources. Nous avons effectué des expérimentations avec JTLN basées sur Alexnet sur les jeux de données de classification d’image et les résultats vérifient l’efficacité du JTLN proposé. A notre connaissances, ce JTLN proposé est le premier travail à aborder ITL avec des réseaux de neurones profond (DNN) tout en intégrant des connaissances antérieures sur la relation entre les catégories cible et source. / When learning a classification model for a new target domain with only a small amount of training samples, brute force application of machine learning algorithms generally leads to over-fitted classifiers with poor generalization skills. On the other hand, collecting a sufficient number of manually labeled training samples may prove very expensive. Transfer Learning methods aim to solve this kind of problems by transferring knowledge from related source domain which has much more data to help classification in the target domain. Depending on different assumptions about target domain and source domain, transfer learning can be further categorized into three categories: Inductive Transfer Learning, Transductive Transfer Learning (Domain Adaptation) and Unsupervised Transfer Learning. We focus on the first one which assumes that the target task and source task are different but related. More specifically, we assume that both target task and source task are classification tasks, while the target categories and source categories are different but related. We propose two different methods to approach this ITL problem. In the first work we propose a new discriminative transfer learning method, namely DTL, combining a series of hypotheses made by both the model learned with target training samples, and the additional models learned with source category samples. Specifically, we use the sparse reconstruction residual as a basic discriminant, and enhance its discriminative power by comparing two residuals from a positive and a negative dictionary. On this basis, we make use of similarities and dissimilarities by choosing both positively correlated and negatively correlated source categories to form additional dictionaries. A new Wilcoxon-Mann-Whitney statistic based cost function is proposed to choose the additional dictionaries with unbalanced training data. Also, two parallel boosting processes are applied to both the positive and negative data distributions to further improve classifier performance. On two different image classification databases, the proposed DTL consistently out performs other state-of-the-art transfer learning methods, while at the same time maintaining very efficient runtime. In the second work we combine the power of Optimal Transport and Deep Neural Networks to tackle the ITL problem. Specifically, we propose a novel method to jointly fine-tune a Deep Neural Network with source data and target data. By adding an Optimal Transport loss (OT loss) between source and target classifier predictions as a constraint on the source classifier, the proposed Joint Transfer Learning Network (JTLN) can effectively learn useful knowledge for target classification from source data. Furthermore, by using different kind of metric as cost matrix for the OT loss, JTLN can incorporate different prior knowledge about the relatedness between target categories and source categories. We carried out experiments with JTLN based on Alexnet on image classification datasets and the results verify the effectiveness of the proposed JTLN in comparison with standard consecutive fine-tuning. To the best of our knowledge, the proposed JTLN is the first work to tackle ITL with Deep Neural Networks while incorporating prior knowledge on relatedness between target and source categories. This Joint Transfer Learning with OT loss is general and can also be applied to other kind of Neural Networks.

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