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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.
211

On developing an unambiguous peatland classification using fusion of IKONOS and LiDAR DEM terrain derivatives – Victor Project, James Bay Lowlands

DiFebo, Antonio January 2011 (has links)
Bogs and fens, which comprise > 90% of the landscape near the De Beers Victor diamond mine, 90 km west of Attawapiskat, ON, provide different hydrological functions in connecting water flow pathways to the regional drainage network. It is essential to define their distribution, area and arrangement to understand the impact of mine dewatering, which is expected to increase groundwater recharge. Classification was achieved by developing a technique that uses IKONOS satellite imagery coupled with LiDAR-derived DEM derivatives to identify peatland classes. A supervised maximum likelihood classification was performed on the 1 m resolution IKONOS Red/Green/Blue without the infrared (RGB) and with the infrared (IR_RGB) band to determine the overall accuracy prior to inclusion of the DEM derivatives. Confusion matrices indicated 62.9% and 65.8% overall accuracy for the RGB and IR_RGB, respectively. Terrain derivatives were computed from the DEM including slope, vertical distance to channel network (VDCN), deviation from mean elevation (DME), percentile (PER) and difference from mean elevation (DiME). These derivatives were computed at a local (15-cell grid size) and meso (250-cell grid size) scale to capture terrain morphology. The mesoscale 250-cell grid analysis produced the most accurate classifications for all derivatives. However, spectral confusion still occurred (regardless of scale) most frequently in the Fen Dense Conifer vs. Bog Dense Conifer classes and also in the Bog Lichen vs. Bog Lichen Conifer. Despite this confusion, by combining the larger scale LiDAR DEM derivatives and the IKONOS imagery it was found that the overall classification accuracy could be improved by 13%. Specifically, the DiME derivative combined with the multispectral IKONOS (IR_RGB) produced an overall accuracy of 76.5%, and increased to 83.7% when Bog Lichen and Bog Lichen Conifer were combined during a post hoc analysis. This classification revealed the landscape composition of the North Granny Creek subwatershed, which is divided into north and south. The north portion comprises 67.4% bog, 13.6% fen and 18.9% water class, while the south is 63.7% bog, 15.2% fen and 21.1% water class. These proportions provide insight into the hydrology of the landscape and are indicative of the storage and conveyance properties of the subwatershed based on the percentage of bog, fen, or open water.
212

Novel Wavelet-Based Statistical Methods with Applications in Classification, Shrinkage, and Nano-Scale Image Analysis

Lavrik, Ilya A. 23 December 2005 (has links)
Given the recent popularity and clear evidence of wide applicability of wavelets, this thesis is devoted to several statistical applications of Wavelet transforms. Statistical multiscale modeling has, in the most recent decade, become a well-established area in both theoretical and applied statistics, with impact on developments in statistical methodology. Wavelet-based methods are important in statistics in areas such as regression, density and function estimation, factor analysis, modeling and forecasting in time series analysis, assessing self-similarity and fractality in data, and spatial statistics. In this thesis we show applicability of the wavelets by considering three problems: First, we consider a binary wavelet-based linear classifier. Both consistency results and implemental issues are addressed. We show that under mild assumptions wavelet-based classification rule is both weakly and strongly universally consistent. The proposed method is illustrated on synthetic data sets in which the truth is known and on applied classification problems from the industrial and bioengineering fields. Second, we develop wavelet shrinkage methodology based on testing multiple hypotheses in the wavelet domain. The shrinkage/thresholding approach by implicit or explicit simultaneous testing of many hypotheses had been considered by many researchers and goes back to the early 1990's. We propose two new approaches to wavelet shrinkage/thresholding based on local False Discovery Rate (FDR), Bayes factors and ordering of posterior probabilities. Finally, we propose a novel method for the analysis of straight-line alignment of features in the images based on Hough and Wavelet transforms. The new method is designed to work specifically with Transmission Electron Microscope (TEM) images taken at nanoscale to detect linear structure formed by the atomic lattice.
213

Malware Classification Based on File and Registry Activities

Zeng, Ling-Ming 12 September 2012 (has links)
Cyber criminals are trying to steal personal information from victim¡¦s machine to acquire more benefits by using malware. Antivirus is the most commonly used tool of malware identification, but the frequency of virus definition update is often less than the frequency of new type malware increase. Therefore, we need an effective and fast tool of malware identification in the current environment. In addition to antivirus, software analysis platform is currently one of the ways to identify malware. User could figure out behaviors of software in detail by the analysis report provided by software analysis platform. Most of software analysis platforms only offer an analysis report, user have to identify whether the software is malware or not by them self. This type of report is no help for user if their expertise not enough to find out these behaviors. Some of software analysis platforms which used antivirus can provide information to user about the software is malware or not, but they don¡¦t have the ability of identifying new type malware immediately. According to research and analysis report, we generalized differences in file and registry activities of normal software and malware and defined malware classification features from these differences. We adopted Support Vector Machine¡]SVM¡^as our algorithm of classification to build and test three classifiers which can identify normal software and malware. After several experimental evaluations, we confirmed that the identification rate of malware was up to 97.6%. Finally, we compared the performance of our classifiers with ThreatExpert, and the result show that the performance of our classifiers is as well as ThreatExpert.
214

Reliability of Lichtman’s classification for Kienböck’s disease in 99 subjects

Shinohara, Takaaki, Koh, Shukuki, Hirata, Hitoshi, Tatebe, Masahiro, Shin, Masaki January 2011 (has links)
名古屋大学博士学位論文 学位の種類 : 博士(医学)(課程) 学位授与年月日:平成23年3月31日 申正樹氏の博士論文として提出された
215

Représentations structurelles parcimonieuses et monodimensionnelles des singularités d'une image application à la classification d'images naturelles /

Ros, Julien Jolion, Jean-Michel Laurent, Christophe January 2007 (has links)
Thèse doctorat : Informatique : Villeurbanne, INSA : 2006. / Thèse entièrement rédigée en anglais. Titre provenant de l'écran-titre. Bibliogr. p. 141-157.
216

Contribution à l'étude et la mise en oeuvre d'indicateurs quantitatifs et qualitatifs d'estimation de la complexité pour la régulation du processus d'auto-organisation d'une structure neuronale modulaire de traitement d'information

Bouyoucef, El Khier Madani, Kurosh. January 2008 (has links) (PDF)
Thèse de doctorat : Sciences informatiques : Paris 12 : 2007. / Thèse uniquement consultable au sein de l'Université Paris 12 (Intranet). Titre provenant de l'écran-titre. Bibliogr. : 77 réf.
217

Méthodes de classification et de segmentation locales non supervisées pour la recherche documentaire

Bellot, Patrice. El-Bèze, Marc. January 2000 (has links) (PDF)
Reproduction de : Thèse doctorat : Informatique : Avignon : 2000. / Titre provenant de l'écran-titre. Bibliogr. p. 159-176.
218

Contribution de la classification automatique à la fouille de données

Jollois, François-Xavier. Margenstern, Maurice January 2008 (has links) (PDF)
Reproduction de : Thèse doctorat : Informatique : Metz : 2003. / Titre provenant de l'écran-titre. Notes bibliographiques.
219

Classification non supervisée avec pondération d'attributs par des méthodes évolutionnaires

Blansché, Alexandre Korczak, Jerzy. Weber, Christiane. January 2007 (has links) (PDF)
Thèse doctorat : Informatique : Strasbourg 1 : 2006. / Titre provenant de l'écran-titre. Bibliogr. 10 p.
220

Towards a natural classification of Plantago : chemical and molecular systematics /

Rønsted, Nina. January 2002 (has links)
Ph.d.

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