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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.
121

Systematics of Brochymena Amyot and Audinet-Serville and Parabrochymena, new genus (Heteroptera: Pentatomidae: Halyini)

Larivière, Marie-Claude January 1990 (has links)
No description available.
122

Systematics of black and white species of the genus Diaphania Hubner (1818) (Lepidoptera:Pyralidae:Pyraustinae)

Clavijo Albertos, Jose Alejandro January 1990 (has links)
No description available.
123

Identification of catalogued and uncatalogued classes /

Lin, Heng-Cheng January 1978 (has links)
No description available.
124

The systematics and phylogeny of Alabagrus (Hymenoptera, Braconidae, Agathidinae) /

Sharkey, Michael Joseph. January 1983 (has links)
Alabagrus is a New World genus of braconid wasps. All Alabagrus are apparently parasitic on leaf rolling and stem boring lepidopterous larvae. Alabagrus is primarily Neotropical with 8 species in the U.S.A. and one species, A. texanus, that reaches southern Ontario and Quebec. / One hundred and eight (108) species are described, keyed and placed in species groups. Eight (8) species have names; most of the remaining 100 species are new to science. Types must be checked in Europe before these species can be named. / Microdus nigrotrochantericus Viereck is synonymized with Bassus imitatus Cresson. A neotype is designated for Bassus sanctus Say. The following new combinations are made: Alabagrus basimaculus (Cameron) from Agathis basimacula, Alabagrus floridanus (Muesebeck) from Bassus floridanus, Alabagrus imitatus (Cresson) from Microdus imitatus, Alabagrus marginatifrons (Muesebeck) from Bassus marginatifrons, Alabagrus sanctus (Say) from Bassus sanctus, Alabagrus simulatrix (Cameron) from Microdus simulatrix, Alabagrus stigmaterus (Cresson) from Microdus stigmaterus, Alabagrus texanus (Cresson) from Microdus texanus.
125

The reliability of esterase patterns in the determination of species of insects in the order Collembola

Hart, John William January 1978 (has links)
Polyacrylamide gel electrophoresis was used to study B-esterases (EC 3.1.1.1) and C-esterases (EC 3.1.1.6) in five species of Collembola--; Folsomia candida, Proisotoma vesiculata, H,ypogastrura denticulata, and two undescribed species of Isotoma,. Ef values were computed for zymograms of 105 individuals and compared both within and among species. Certain bands-three to six in number--predominated on the zymograms of each species. The predominating bands differed among the five species resulting in a unique zymogram for each.It was also found that zymograms of normal and ecomorphic forms of Proisotoma vesiculata were dissimilar. Zymograms of specimens of Folsomia candida with access to food and those without food for 48 and 72 hours were similar. Zymograms from mascerated specimens frozen in buffer were not satisfactory.
126

The systematics and phylogeny of Alabagrus (Hymenoptera, Braconidae, Agathidinae) /

Sharkey, Michael Joseph. January 1983 (has links)
No description available.
127

Classification de textes : de nouvelles pondérations adaptées aux petits volumes / Text Classification : new weights suitable for small dataset

Bouillot, Flavien 16 April 2015 (has links)
Au quotidien, le réflexe de classifier est omniprésent et inconscient. Par exemple dans le processus de prise de décision où face à un élément (un objet, un événement, une personne) nous allons instinctivement chercher à rapprocher cet élément d'autres similaires afin d'adapter nos choix et nos comportements. Ce rangement dans telle ou telle catégorie repose sur les expériences passées et les caractéristiques de l'élément. Plus les expériences seront nombreuses et les caractéristiques détaillées, plus fine et pertinente sera la décision. Il en est de même lorsqu'il nous faut catégoriser un document en fonction de son contenu. Par exemple détecter s'il s'agit d'un conte pour enfants ou d'un traité de philosophie. Ce traitement est bien sûr d'autant plus efficace si nous possédons un grand nombre d'ouvrages de ces deux catégories et que l'ouvrage à classifier possède un nombre important de mots.Dans ce manuscrit nous nous intéressons à la problématique de la prise de décision lorsque justement nous disposons de peu de documents d'apprentissage et que le document possède un nombre de mots limité. Nous proposons pour cela une nouvelle approche qui repose sur de nouvelles pondérations. Elle nous permet de déterminer avec précision l'importance à accorder aux mots composant le document.Afin d'optimiser les traitements, nous proposons une approche paramétrable. Cinq paramètres rendent notre approche adaptable, quel que soit le problème de classification donné. De très nombreuses expérimentations ont été menées sur différents types de documents, dans différentes langues et dans différentes configurations. Selon les corpus, elles mettent en évidence que notre proposition nous permet d'obtenir des résultats supérieurs en comparaison avec les meilleures approches de la littérature pour traiter les problématiques de petits volumes.L'utilisation de paramètres introduit bien sur une complexité supplémentaire puisqu'il faut alors déterminer les valeurs optimales. Détecter les meilleurs paramètres et les meilleurs algorithmes est une tâche compliquée dont la difficulté est théorisée au travers du théorème du No-Free-Lunch. Nous traitons cette seconde problématique en proposant une nouvelle approche de méta-classification reposant sur les notions de distances et de similarités sémantiques. Plus précisément nous proposons de nouveaux méta-descripteurs adaptés dans un contexte de classification de documents. Cette approche originale nous permet d'obtenir des résultats similaires aux meilleures approches de la littérature tout en offrant des qualités supplémentaires.Pour conclure, les travaux présentés dans ce manuscrit ont fait l'objet de diverses implémentations techniques, une dans le logiciel Weka, une dans un prototype industriel et enfin une troisième dans le logiciel de la société ayant financé ces travaux. / Every day, classification is omnipresent and unconscious. For example in the process of decision when faced with something (an object, an event, a person), we will instinctively think of similar elements in order to adapt our choices and behaviors. This storage in a particular category is based on past experiences and characteristics of the element. The largest and the most accurate will be experiments, the most relevant will be the decision. It is the same when we need to categorize a document based on its content. For example detect if there is a children's story or a philosophical treatise. This treatment is of course more effective if we have a large number of works of these two categories and if books had a large number of words. In this thesis we address the problem of decision making precisely when we have few learning documents and when the documents had a limited number of words. For this we propose a new approach based on new weights. It enables us to accurately determine the weight to be given to the words which compose the document.To optimize treatment, we propose a configurable approach. Five parameters make our adaptable approach, regardless of the classification given problem. Numerous experiments have been conducted on various types of documents in different languages and in different configurations. According to the corpus, they highlight that our proposal allows us to achieve superior results in comparison with the best approaches in the literature to address the problems of small dataset. The use of parameters adds complexity since it is then necessary to determine optimitales values. Detect the best settings and best algorithms is a complicated task whose difficulty is theorized through the theorem of No-Free-Lunch. We treat this second problem by proposing a new meta-classification approach based on the concepts of distance and semantic similarities. Specifically we propose new meta-features to deal in the context of classification of documents. This original approach allows us to achieve similar results with the best approaches to literature while providing additional features. In conclusion, the work presented in this manuscript has been integrated into various technical implementations, one in the Weka software, one in a industrial prototype and a third in the product of the company that funded this work.
128

A Synopsis of the Canadian Thysanoptera

Chiasson, Hélène January 1985 (has links)
Note: page 74 is missing from archival and circulating copies / The present state af knowledge of the order Thysanaptera in Canada is reviewed. The aoder has been sorely neglected since Provenchar submitted a list af 35 eastern Canadian species in 1890. In contrast to the latest previaus estimate of 102 species (Heming, 1979), the number of species found in this study is 174 (143 described and 31 undescribed species). One new genus and five new species are reported as well as the European species Odontothrips biuncus which has been found for the first time in North America. Descriptions, illustrations and a dichatamaus key to the Canadian genera of the Thysanaptera ara given for the first time. Also included are lists of the species. hitherto found in Canada along with their localities•• and habitats•• In addition, an alternative computer-compatible key is presented for the suborder Tubullfera. The distribution and study af the order in Canada are discussed and notes on collection, classification, biology and economic importance are given. / Ce travail revise l’etat de nos cannais.ance. sur l’ordre de. Thysanopteres au Canada. Ce groupe a fait l’objet de peu d’etudes depuis la publication de Provencher (1890), qui enumerait 35 especes pour l’est du Canada. Dans la presente etude, nous rapportons . 174 especes (143 especes decrites, 31 especes non decrit••) alors qu’Heming (1979) n’en citait que 102 especes. pour ce pays. On y cree un nouveau genre et 5 nouvelles especes, en plus de recolter pour la premiere fois l’espece europeanne, Odonthrips biuncus en Amerique du Nord. L’auteur decrit et illustre pour la premiere fois. les. genres de Thvsanoptere. representes dans la fauna canadienne. De plus, on y trouve une liste des especes presentes au Canada, accompagnee de notes sur leur repartition geographique et leur habitat. On y inclut un tableau dichotomique conventionnel ainsi qu’un tableau de determination adape a l’ordinateur. pour Ie sous-ordre des Tubuliferes. Ce travail fournit egalemant, pour les Thysanopteres du Canada, une discussion sur leur repartition Geographique et des renseignements sur leur recolte et classification, leur biologie et importance economique.
129

The systematics, zoogeography and evolution of Dolly Varden and bull trout in British Columbia

Haas, Gordon Robert January 1988 (has links)
An analysis of the systematics, zoogeography and evolution of the Dolly Varden char species complex in British Columbia is presented. These features of this species complex and the morphometric statistical procedures used in these analyses have both long been the subjects of strong debate and also have recently seen much renewed interest and work. This thesis assesses both these areas and is divided into those two parts. The first section deals with these three biological topics, and the second section contains a synthesis and exploratory data assessment of the commonly used morphometric techniques and provides some new methodology for understanding their requirements and interpreting their results. PART I 1. The systematics of the Dolly Varden char species complex is examined by using principal component analysis (PCA) to designate typological species groupings and then employing linear discriminant function analysis on a reduced set of significant characters to classify the remaining specimens. This typological distinction is verified with distributional information that reveals no interbreeding of the species in areas of parapatry and sympatry, and with preliminary information regarding intra- and inter- specific crosses, spawning colouration, skull osteology, cytology and embryology. This data is also suggestive of competitive exclusion and character displacement. All these results indicate that the Dolly Varden char species complex in B.C. is composed of two species, Dolly Varden (Salvelinus malma) and bull trout (Salvelinus confluentus). 2. The zoogeography of these two species is analyzed using canonical trend surface analysis (CTS). CTS can potentially separate confounding non-geographic morphometric information from the data and thus could allow historical zoogeograpbic patterns to be inferred from that data which corresponds to geography. Such a reconstruction reveals the possible glacial refuge origins and post-glacial recolonization patterns of these two species for each of the major river drainages in B.C.. 3. The evolution of these two species is assessed through the implementation of PCA to fit the cross-sectional morphometric data to an ontogenetic model. The resultant PCA size and shape vectors effectively portray allometric trends which indicate that Dolly Varden could have evolved from bull trout through neotenic paedomorphosis. This result is supported with data on growth rates and developmental homeostasis. PART II 4. A synthesis of the available but widely scattered and disparate information on the data and statistical requirements for morphometric statistics reveals the analytical problems that can result from not approximating underlying test assumptions. These assumptions are important, but are not appreciated or often assessed. Simple recommendations and rarely used tests for dealing with these requirements are provided. 5. The effectiveness and compatability of four bivariate morphometric techniques (ratios, log₁₀ ratios, allometric regression, regression residuals) are assessed. All methods provide similar but ineffective individual ordination and group separation. Their effects on characters differ greatly and are often unrealistic. None of these methods effectively removes all the confounding allometric size information, but allometric regression will usually be the best bivariate procedure. 6. A similar assessment of four multivariate morphometric procedures (covariance matrix PCA, correlation matrix PCA, shear matrix PCA, size-constrained matrix PCA) is undertaken. Size-constrained PCA results in non-orthogonal vectors that also do not represent the traditional multivariate morphometric size and shape vectors. As well, the character and individual information it provides is unrealistic. The other three techniques result in similar and effective individual ordination, group separation and removal of confounding allometric size information. PCA on a covariance matrix is likely the best multivariate method since it provides the most realistic size adjustment and character information. 7. PCA is often carried out on data which has been previously adjusted through bivariate procedures. An examination of this method demonstrates that it results in no benefits since the multivariate morphometric size and shape vectors are lost, and the data variation is no longer synthesized into only two or three resultant significant vectors. 8. PCA is also performed on mixed character data sets (continuous and discontinuous data). An assessment of this procedure shows that it provides improved group separation, but the representation of characters, individuals and multivariate morphometric size and shape relationships is confounded and unrealistic. There also is a slight reduction in data synthesis. 9. A methodology for back-transforming PCA output into the original and more intuitively comprehensible data scale, format and dimensions is given. This back-transformation also verifies the traditional belief that the first resultant PCA morphometric vector is size and that the second is shape. Separate unconfounded matrices for size and shape information in which only the significant data variation is accounted for can thus be independently back transformed. / Science, Faculty of / Zoology, Department of / Graduate
130

A Synopsis of the Canadian Thysanoptera

Chiasson, Hélène January 1985 (has links)
Note: page 74 is missing from archival and circulating copies

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