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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.
391

Geometrická teorie řízení na nilpotentních Lieových grupách / Geometric control theory on nilpotent Lie groups

Frolík, Stanislav January 2019 (has links)
This thesis deals with the theory of geometric control of the trident robot. The thesis describes the basic concepts of differential geometry and control theory, which are subsequently used for describing various mechanisms. Finally, the thesis proposes the management using inferred results.
392

Predikce koroze trubek pece s využitím provozních dat / Prediction of furnace tubes corrosion using operating data

Kolomazník, Milan January 2014 (has links)
The thesis deals with the modeling and prediction of corrosion of radiation tube snake in the heating furnace. Specifically it is focused on vertical cylindrical furnace which is included in the catalytic hydrocracking unit and serves for heating aggressive circulation gas which is the cause of high temperature corrosion. An important basis for the creation of computational models are available records about the operation of the furnace and about the corrosion and degradation mechanisms during the lifetime of the tube system in furnace. Such information enables the creation of a computational model which is based on the prediction of high-temperature corrosive damage of radiation tube snake. The computational model involving all relevant factors may serve as the basis for a predictive life management system of radiation snakes in the heating furnace.
393

Had jako prostředek reflexe v textech o umělcích z období německého romantismu / The Snake as Means of Reflection in the Texts about Artists from the German Romantic Period

Balcarová, Markéta January 2016 (has links)
The submitted doctoral thesis examines the function and performance of the motive of a snake in four selected texts about artists of the German romantic period and perceives the snake as an attribute reflecting the problems of the artistic existence and a way to the artistic work, possibly of the artistic work at all. When interpreting the single motives of the snake, three-phase procedure as applied by Erwin Panofsky in description of the motives in the pictures has been chosen by analogy for literary texts. The interpretation is based on the structural position of the motive of the snake in the text and its performance in the text. Subsequently, the principal role is revelation of contexts which updates the given motive of the snake - in particular they are biblical snakes, mythical snakes and a serpentine line as a line of beauty which was the subject of the period aesthetic discourse. The meaning of the motive of the snake in the texts is given primarily by the mutual interaction of theme contexts which is in the single texts realized by various ways. The motive of the snake as formed in the single interpreted texts is a highly complex motive in all the cases. Thanks to the possibility of connotation with the snakes from the sphere of the Bible and mythology the literary motive of the snake becomes a...
394

Fungal and Bacterial Populations on <i>Clemmys guttata</i> and <i>Chrysemys picta</i> in Clark County, Ohio, and <i>Kinosternon steindachneri</i> and <i>Virginia valeriae</i> in Lafayette County, Mississippi

Paazig, Josie 22 June 2022 (has links)
No description available.
395

Exploring Great Basin National Park using a high-resolution Embedded Sensor Network

Sambuco, Emily Nicole 28 August 2019 (has links)
No description available.
396

Habitat, ecology, and venom variation of cobras (genus Naja) and other venomous snakes of Bangladesh

Chowdhury, Mohammad Abdul Wahed 20 April 2022 (has links)
Im Fokus dieser Dissertation steht die Zerstörung des Lebensraumes von Schlangen durch anthropogene Einflüsse im Zusammenhang mit dem Auftreten von Schlangenbissen bei Menschen. Zum Schutz der Schlangen und dem Problem der Schlangenbisse wurden vier wesentliche Anforderungen erarbeitet. Mit Hilfe eines Artenverteilungsmodells wurden die ökologischen Nischen von 29 Giftschlangenarten aus Bangladesch und von zehn Kobraarten (Naja) aus Asien ermittelt. Auf lokaler Ebene wurde festgestellt, dass Überschwemmungen, Waldtypen, Ökosysteme und klimatische Parameter das Verbreitungsgebiet der Schlangenarten in Bangladesch beeinflussen. Auf regionaler Ebene sind anthropogene Faktoren wie die Zerstörung von Schlangenlebensräumen, Handel, Ausbeutung und Tötung von Schlangen wahrscheinlich die Hauptursachen für den Rückgang der Populationen der asiatischen Naja. Auf beiden Ebenen führt der Klimawandel zu einer Verkleinerung der ökologischen Nischen von Schlangenarten in Bangladesch und Asien. In Bangladesch könnten die untersuchten Arten innerhalb der nächsten 50 Jahre mehr als 90 % ihren derzeitigen Lebensraum verlieren (Asiatische Naja durchschnittlich 56 % (12 bis 100 %)). Wenn günstige Nischen nicht erhalten werden können, könnten viele Schlangenarten in einigen Ländern Asiens, darunter Bangladesch, in wenigen Jahrzehnten aussterben. Darüber hinaus wurde in der vorliegenden Studie geschätzt, dass die Zahl der jährlichen Schlangenbisse in Bangladesch mehr als doppelt so hoch sein könnte wie bisher angenommen. Da der Klimawandel zu einer geografischen Verschiebung günstiger Nischen führen kann, kann sich diese Veränderung auch auf die Häufigkeit von Schlangenbissen auswirken. Bei der Analyse von Giftvariationen und der Wirksamkeit von Antivenomen wurde festgestellt, dass isolierte Populationen deutliche intraspezifischere Giftvariationen zeigen. / Snakes are threatened by habitat degradation and anthropogenic impacts, while accidental encounters between humans and snakes may result in snakebite incidents. Thus, the conservation of snakes snakebite problem, a global public health emergency, are interconnected. I found four primary needs for a combined solution to satisfy both above causes. A species distribution model was employed to identify the ecological niches of 29 venomous snake species from Bangladesh and of ten cobra species (Naja) from Asia. At the local scale, flood events, forest types, ecosystems, and climatic parameters were found to shape the range of snake species in Bangladesh. At the regional scale, anthropogenic factors, like snake habitat destruction, trade, exploitation, and snake killings are likely to be the main causes for the decrease in populations of Asian Naja. At both levels, climate change causes shrinking and fragmenting the ecological niches of snake species in Bangladesh and Asia. In Bangladesh, the studied species may lose more than 90% of their current climatic niche within the next 50 years. In the same timeframe, Asiatic Naja may lose an average of 56% (12- 100%) of the area of suitable climatic niches. If favourable niches cannot be preserved, many snake species might go extinct from several countries in Asia in a few decades, including Bangladesh. In addition, the present study estimated that there might be more than double the amount of annual snakebite incidents in Bangladesh than previously estimated. As climate change may cause geographical shifting of favourable niches, this change may also have consequences for the frequency of snakebites, so snakebite should be considered a climate driven dynamic public health problem. While analysing venom variations and the efficacy of antivenom, I found that venom should be sampled from geographically or ecologically isolated populations of each venomous snake, because isolated populations have shown distinct intraspecific venom variations.
397

The serpent handlers from the Appalachian mountains in the southern states of the USA

Meister, Inga Maja 01 January 2002 (has links)
Text in English / The southern Appalachian mountain region is home to a sincere group of religious fundamentalists. They obey Jesus' last command that serpents should be taken up (Mark 16:17-18). They believe the Holy Ghost anoints them and gives them the power to handle serpents, drink poisons, handle fire, and to heal the sick. Nevertheless, they are fully aware that they may be bitten and may even die. Each church is autonomous. / Religious Studies and Arabic / M.A. (Religious Studies)
398

Marche aléatoire indexée par un arbre et marche aléatoire sur un arbre / Tree-indexed random walk and random walk on trees

Lin, Shen 08 December 2014 (has links)
L’objet de cette thèse est d’étudier plusieurs modèles probabilistes reliant les marches aléatoires et les arbres aléatoires issus de processus de branchement critiques.Dans la première partie, nous nous intéressons au modèle de marche aléatoire à valeurs dans un réseau euclidien et indexée par un arbre de Galton–Watson critique conditionné par la taille. Sous certaines hypothèses sur la loi de reproduction critique et la loi de saut centrée, nous obtenons, dans toutes les dimensions, la vitesse de croissance asymptotique du nombre de points visités par cette marche, lorsque la taille de l’arbre tend vers l’infini. Ces résultats nous permettent aussi de décrire le comportement asymptotique du nombre de points visités par une marche aléatoire branchante, quand la taille de la population initiale tend vers l’infini. Nous traitons également en parallèle certains cas où la marche aléatoire possède une dérive constante non nulle.Dans la deuxième partie, nous nous concentrons sur les propriétés fractales de la mesure harmonique des grands arbres de Galton–Watson critiques. On comprend par mesure harmonique la distribution de sortie, hors d’une boule centrée à la racine de l’arbre, d’une marche aléatoire simple sur cet arbre. Lorsque la loi de reproduction critique appartient au domaine d’attraction d’une loi stable, nous prouvons que la masse de la mesure harmonique est asymptotiquement concentrée sur une partie de la frontière, cette partie ayant une taille négligeable par rapport à celle de la frontière. En supposant que la loi de reproduction critique a une variance finie, nous arrivons à évaluer la masse de la mesure harmonique portée par un sommet de la frontière choisi uniformément au hasard. / The aim of this Ph. D. thesis is to study several probabilistic models linking the random walks and the random trees arising from critical branching processes.In the first part, we consider the model of random walk taking values in a Euclidean lattice and indexed by a critical Galton–Watson tree conditioned by the total progeny. Under some assumptions on the critical offspring distribution and the centered jump distribution, we obtain, in all dimensions, the asymptotic growth rate of the range of this random walk, when the size of the tree tends to infinity. These results also allow us to describe the asymptotic behavior of the range of a branching random walk, when the size of the initial population goes to infinity. In parallel, we treat likewise some cases where the random walk has a non-zero constant drift.In the second part, we focus on the fractal properties of the harmonic measure on large critical Galton–Watson trees. By harmonic measure, we mean the exit distribution from a ball centered at the root of the tree by simple random walk on this tree. If the critical offspring distribution is in the domain of attraction of a stable distribution, we prove that the mass of the harmonic measure is asymptotically concentrated on a boundary subset of negligible size with respect to that of the boundary. Assuming that the critical offspring distribution has a finite variance, we are able to calculate the mass of the harmonic measure carried by a random vertex uniformly chosen from the boundary.
399

Les récits persans en prose en Inde : exemple : Touti-Nâme / Persians narratives in India : example : Touti-Nâme

Shahbaz, Pegah 30 September 2014 (has links)
Ce travail de recherche vise à présenter une collection de récits traditionnels persans, soit tirés et traduits des ressources indiennes, soit écrits et composés directement en persan dans le sous-continent. Notre attention s'est portée sur les récits en prose qui détiennent plusieurs emprunts de la tradition et la culture indienne, et ceux qui sont enrichis par des éléments narratifs et imaginaires fabuleux. Ces spécificités apparaissent dans de divers aspects : la structure du récit-cadre, les thèmes principaux et les personnages des contes. Les récits indo-persans sélectionnés sont présentés en détail par des informations sur leurs auteurs / traducteurs, la date et le lieu de composition, leurs thématiques, leurs sources originales, les manuscrits disponibles et d'autres références. La recherche actuelle est également un effort pour la pratique et le développement de la perception symbolique dans les récits classiques. Touti-Nâme, choisi comme le corpus de notre étude, nous fournit des scènes sur la vie sociale, les relations intimes et conjugales dans les contextes individuels et sociaux. J’ai examiné les thèmes dominants de la ruse des femmes, du conflit entre le désir et la loi, du rêve et du rire à travers des approches mythiques et symboliques. Le rôle prépondérant des personnages féminins et des perroquets sont étudiés profondément dans les contes. J'ai aussi essayé d'analyser les aspects psychiques des personnages par le biais de l'approche psychanalytique jungienne. Des exemples concrets de l'autorité et des jeux de pouvoir entre les sexes sont donnés dans Touti-Nâme comme spécificité des sociétés traditionnelles patriarcales. / The present research aims to introduce a collection of Persian traditional narratives, either translated from Indian sources, or written and composed directly into Persian language in the sub-continent. Our focus has been on prose narratives which hold multiple specificities borrowed from Indian tradition and culture, and are enriched by fabulous and imaginary narrative elements. Such specificities appear in diverse aspects : the frame structure of the stories, the leading themes and the typical Indian characters. These stories are presented in detail by providing information about their authors / translators, date and place of composition, themes, original sources, available manuscripts and other references.The current research is also an endeavor to practice and develop symbolic perception in classical stories. Touti-Nâme, chosen as our target text, demonstrates social life, conjugal relationships and power-struggle in both individual and social contexts. The dominant themes of women’s guiles and tricks, love and law conflict, dream and laughter have been examined through mythical and symbolic approaches. Women characters and birds such as parrots have gone through profound studies due to their predominant roles within the tales. I have also tried to study psychological aspects of story characters and their role in the events by means of the Jungian psychoanalytical approach. Concrete examples of gender authority and power-games in traditional patriarchal societies have been given in Touti-Nâme.
400

Avaliação in vitro da permeabilidade cutânea da rutina em emulsões cosméticas / In vitro evaluation of rutin cutaneous permeability from cosmetic emulsions

Baby, André Rolim 10 September 2007 (has links)
A rutina é empregada como antioxidante e na prevenção da fragilidade capilar. Pode ser veiculada em emulsões tópicas adequadas para atingir o local de ação. Estudos de penetração in vitro através da pele humana seria a situação ideal, entretanto, há dificuldades de sua obtenção e manutenção de sua viabilidade. Entre os demais modelos de membrana, a muda de pele de cobra apresenta-se como estrato córneo puro, fornecendo barreira similar ao humano e é obtida sem a morte do animal. Os objetivos desta pesquisa foram: (1) desenvolver e avaliar a estabilidade de emulsões cosméticas, contendo rutina e promotores de penetração cutânea, tais como, uréia (U), isopropanol (IP) e propilenoglicol (PG); (2) avaliar a liberação da referida substância ativa das emulsões e; (3) avaliar a penetração e a retenção cutânea in vitro da rutina da formulação de melhor desempenho. Emulsões foram desenvolvidas com rutina a 5,0% p/p e U, IP e PG, associados ou não e em proporções distintas, segundo planejamento fatorial com dois níveis com ponto central. Quantificou-se a rutina das emulsões por espectrofotometria a 361,0 nm, método previamente validado. A liberação da rutina nas formulações foi realizada em células de difusão vertical com membrana de acetato de celulose e água destilada e álcool etílico absoluto 99,5% (1:1), como fluido receptor. O experimento foi conduzido em um período de seis horas, a 37,0 ±. 0,5 &#176;C e agitação constante de 300 rpm.>f. emulsão de melhor desempenho quanto à liberação foi estudada quanto à estabilidade (Testes de Estabilidade Acelerada). Para o estudo de penetração e retenção cutânea da rutina dessa formulação foi utilizada muda de pele de cobra de Crotalus durissus. Empregou-se o método espectrofotométrico validado a 410,0 nm para a quantificação da rutina após liberação, penetração e retenção cutânea. Todas as emulsões foram consideradas adequadas após desenvolvimento das formulações. A uréia (isolada e em associação com IP e PG) e o isopropanol (isolado e em associação com PG) influenciaram negativamente a liberação da rutina das emulsões em diversos parâmetros. A rutina liberada e acumulada da formulação contendo PG a 5,0% p/p possuiu valor de 648,80 ±. 53,01 &#181g/cm2. Fora do esperado, a preparação contendo o número maior de promotores (U 5,0% p/p, IP 5,0% p/p e PG 5,0% p/p) resultou em liberação de menor magnitude igual a 419,76 ±. 17,98 &#181g/cm2. A presença do PG apresentou-se mais eficiente na liberação da rutina, mas não na sua penetração através da muda de pele de C. durissus, retendo 0,931 ± 0,0391 &#181;g de rutina/mg de muda de pele de cobra. Nas condições de armazenamento a 25,0 ±2,0 &#176;C; 5,0 ±0,5 &#176;C e 45,0 ±. 0,5 &#176;C, a emulsão com PG e rutina apresentou-se quimicamente estável durante 30 dias. De acordo com os resultados, a emulsão contendo PG apresentou liberação mais expressiva da rutina, no entanto, não ocorreu a penetração cutânea, mas apenas sua retenção no estrato córneo de C. durissus. A preparação manteve-se estável em todas as condições de armazenamento. / Rutin is employed as antioxidant and to prevent the capillary fragility and, when incorporated in cosmetic emulsions, it must target the action site. In vitro cutaneous penetration studies through human skin is the ideal situation, however, there are difficulties to obtain and to maintain this tissue viability. Among the membrane models, the shed snake skin presents itself as pure stratum corneum, providing barrier function similar to human and it is obtained without the animal sacrifica. The objectives of this research were: (1) development and stability evaluation of cosmetic emulsions containing rutin and penetration enhancers, as urea (U), isopropanol (IP) and propylene glycol (PG); (2) release evaluation of the mentioned active substance from the emulsions and; (3) evaluation of rutin in vitro cutaneous penetration and retention from the emulsion of the best performance. Emulsions were developed with rutin 5.0% w/wand U, IP and PG, associated or not according to factorial design with two levels and central point. Active substance on the formulations was quantified by a validated spectrophotometric method at 361.0 nm. Rutin release from emulsions was performed in vertical diffusion cells with cellulose acetate membrane and distilled water and ethanol 99.5% (1:1), as receptor fluid. The experiment was conducted for six hours, at 37.0 ± 0.5 °c with constant stirring of 300 rpm. Formulation with best profile of rutin release had its stability studied by the Accelerated Stability Assays. Rutin cutaneous penetration and retention from the mentioned emulsion was performed with shed snake skin from Crotalus durissus. Spectrophotometry at 410.0 nm, previously validated, determined the active substance after release and cutaneous penetration/retention. Ali emulsions were considered apparently stables after development. Urea (isolated and associated with IP and PG) and isopropanol (isolated and associated with PG) have influenced negatively the rutin release in several parameters. Emulsion with PG 5.0% w/w presented rutin released and accumulated equal to 648.80 ± 53.01 &#181;g/cm2. Unexpectedly, the formulation containing all enhancers (U 5.0% w/w, IP 5.0% w/w and PG 5.0% w/w) has decreased the amount released of the active substance (419.76 ± 17.98 &#181;g/cm2). Emulsion with PG presented more adequate for rutin release, but PG did not provide rutin cutaneous penetration through C. durissus skin, retaining 0.931 ± 0.0391 &$181;g rutin/mg shed snake skin. The referred formulation was chemically stable for 30 days after they have been stored at 25.0 ± 2.0 &#176;c, 5.0 ± 0.5 &#176;c and 45.0 ± 0.5 &#176;C. In conclusion, emulsion with PG provided rutin release more expressively, although, it has not been verified the active cutaneous penetration, but only its retention on the Crotalus durissus stratum corneum. Formulation was stable in all storage conditions.

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