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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.
261

Desenvolvimento de um aplicativo computacional para dimensionamento técnico e econômico de biodigestores tipo tubular / Development of an computacional application for technical and economical sizing of tubular type biodigesters

Alves , Anelisiane Maria 23 March 2017 (has links)
Submitted by Rosangela Silva (rosangela.silva3@unioeste.br) on 2017-09-04T19:21:36Z No. of bitstreams: 2 Anelisiane Maria Alves.pdf: 2439673 bytes, checksum: fd370a11122ff19c0d83073490e93fb3 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-09-04T19:21:36Z (GMT). No. of bitstreams: 2 Anelisiane Maria Alves.pdf: 2439673 bytes, checksum: fd370a11122ff19c0d83073490e93fb3 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-03-23 / Technological and economic development occurred through the extraction of the environment and industrialization in a globalized model of society. This model is now fully dependent on sources of energy to continue to function. However, due to the environmental politicization and the problematization of the use of fossil sources, the search for an alternative energy model has been the subject of academic research and public policies for some years. The present work focuses on the development of a computational program that will provide the user, often unaware of the research in development, with the access and the necessary guidance for the implantation of a tubular rural biodigester. The application was developed in Java language, where the technical and economical sizing methodology used takes into account data such as the type and number of animals and the user's monthly electricity consumption. After the program processes the calculation routine, the user is presented the results in 3 different screens, one containing a generic image with the nomenclature adopted for the estimated dimensions, a screen with technical information of the design and a final screen with information of economic projection. This work is expected to disseminate and democratize alternative research and technologies through the use of digital technology. / O desenvolvimento tecnológico e econômico ocorreu através do extrativismo do meio ambiente e da industrialização em um modelo globalizado de sociedade. Esse modelo encontra-se hoje plenamente depende de fontes de energias para continuar funcionando. Entretanto, em decorrência da politização ambiental e da problematização quanto ao uso de fontes fósseis, a busca por um modelo energético alternativo tem sido tema de pesquisas acadêmicas e políticas públicas há alguns anos. O presente trabalho tem como foco o desenvolvimento de um programa computacional o qual proporcionará ao usuário, muitas vezes alheio às pesquisas em desenvolvimento, o acesso e o direcionamento necessários para a implantação de um biodigestor rural tubular, devendo ser informados apenas alguns dados bases. O aplicativo foi desenvolvido em linguagem Java, onde a metodologia de dimensionamento técnico e econômico utilizada levam em conta dados como o tipo e número de animais e o consumo mensal de energia elétrica do usuário. Após o programa processar a rotina de cálculos, é apresentado ao usuário os resultados em 3 telas diferentes, uma contendo uma imagem genérica com a nomenclatura adotada para as dimensões estimadas, uma tela com informações técnicas do dimensionamento e uma tela final com informações de projeção econômica. Espera-se com esse trabalho a difusão e a democratização de pesquisas e tecnologias alternativas através do uso da tecnologia digital.
262

Influência do tratamento térmico de alívio de tensões pós-soldagem na microestrutura e comportamento mecânico de soldas produzidas com arame tubular rutílico / Influence of Postweld Heat Treatment in Microstructure and Mechanical Behavior of Weld Obtained by Rutile Flux-Cored Wire

José Mauro Moraes Junior 02 September 2008 (has links)
O objetivo desta Dissertação foi analisar o efeito do tratamento térmico de alívio de tensões pós-soldagem sobre a microestrutura e comportamento mecânico de soldas produzidas com arame tubular rutílico AWS E-81T1 Ni1. Foi soldada uma junta com 60 mm de espessura, na posição vertical e progressão ascendente. Esta junta foi dividida em três partes, sendo uma mantida como soldada e as outras duas tratadas termicamente por 6 horas em diferentes temperaturas, 585 °C e 650 °C. Avaliou-se o efeito do tratamento térmico sobre as propriedades mecânicas por meio de ensaio de dureza, tração e impacto Charpy-V. A caracterização microestrutural foi realizada por microscopia óptica e microscopia eletrônica de varredura. As observações experimentais mostraram uma diminuição da tenacidade ao impacto no material tratado termicamente, com uma tendência para uma queda maior com o aumento da temperatura do tratamento térmico. Este comportamento pode ser atribuído principalmente à precipitação e crescimento de carbonetos. Não foi observada a presença de mecanismos de fratura intergranular. Provavelmente o metal de solda estudado não possuía nível de impurezas suficiente para a ativação deste mecanismo. / The objective of this Dissertation was to analyze the effect of postweld heat treatment on microstructure and mechanical behavior of welds obtained by flux cored wire AWS E-81T1 Ni1. It was welded a joint with 60 mm thickness, on vertical position and ascendant progress. This joint was divided in three parts, one maintained as welded and two others heat treated for 6 hours on different temperatures, 585 °C and 650 °C. The effect of the heat treatment on mechanical properties was evaluated by means of hardness, tensile and impact Charpy-V tests. The characterization of the microstructure was undertaken utilizing optical and scanning electron microscopy. The experimental results revealed a decrease of impact toughness in heat treated material, with a tendency to a low impact toughness for high heat treatment temperature. This behavior may principally be attributed to an increase precipitation and growth of carbides. No intergranular fracture mechanism was observed. Probably the level of impurities in the weld metal studied was not high enough to provoke such phenomena.
263

Caractérisation géométrique d’organes tubulaires / Geometrical analysis of tubular organs

Grelard, Florent 04 December 2017 (has links)
Cette thèse s’inscrit dans un contexte d’analyse d’images médicales et s’attache plus particulièrement à l’étude des organes tubulaires (vaisseaux, bronches, neurones...). De nombreuses pathologies, telles que les bronchopneumopathies chroniques obstructives (BPCO) pour les bronches, affectent la structure des organes tubulaires. Des outils automatiques sont nécessaires afin d’effectuer des mesures précises, reproductibles et permettant un suivi dans le temps. L’objectif de la thèse est de proposer de nouveaux outils facilitant la caractérisation automatique de ces organes. Cette caractérisation se base le plus souvent sur l’analyse de la géométrie de l’organe segmenté. Il existe de nombreuses méthodes permettant d’effectuer des mesures géométriques, mais certaines nécessitent d’extraire des sous-représentations de l’organe. Dans le cadre de cette thèse, nous nous intéressons à deux de celles-ci : le squelette curvilinéaire et les plans de coupe 2D reconstruits orthogonalement à l’axe de l’organe. Notre première contribution est une méthode d’estimation précise des plans orthogonaux. Nous avons également proposé un algorithme de squelettisation spécifique aux organes tubulaires, ainsi que des outils d’amélioration de squelettes existants. De plus, nous présentons à la fin de ce document, un travail en cours sur une méthode de filtrage de structures tubulaires à partir d’images en niveaux de gris. / This thesis is dedicated to the study of tubular organs, such as blood vessels, bronchii, or neurons. Several diseases, such as chronic obstructive pulmonary disease (COPD) for bronchii, distort the structure of tubular organs. Several tools are necessary in order to make precise and reproducible measurements and to track the organ over time. The main goal of this thesis is to define new tools for the automatic characterization of tubular organs. This characterization is based on the geometrical analysis from a segmentation. There are various state-of-the-art methods to perform geometrical measurements, but some of them require to extract alternative representations from the organ. In this thesis, we focus on two of these : curvilinear skeletons and 2D planes computed from the axis of the tube. Our first contribution is a method for the precise estimation of orthogonal planes. In addition, we propose a skeletonization algorithm as well as methods to improve existing skeletons. At the end of this manuscript, we introduce a method from a work in progress which allows to filter tubular structures in grayscale images.
264

Physiologie et Physiopathologie du transport de chlore dans le canal collecteur rénal : caractérisation d’un modèle murin d’Acidose tubulaire rénale distale et Étude des mécanismes de régulation du canal ClC-Kb/Barttin / Physiology and Pathophysiology of the chloride transport in renal collecting duct : characterization of a mouse model of distal renal tubular acidosis and Study of the mechanisms of regulation of ClC-Kb/Barttin channel

Serbin, Bettina 24 June 2016 (has links)
Le rein joue un rôle crucial dans de multiples processus biologiques, tels que le maintien de l’homéostasie acide-base et de la balance sodée. Le transport de chlore dans le néphron distal est un élément majeur de ces deux fonctions physiologiques. Au cours de ma thèse, j’ai travaillé sur deux projets relatifs à la physiologie et la physiopathologie du transport de chlore dans le néphron distal. Le premier travail concerne la caractérisation fonctionnelle et moléculaire d’un modèle murin dont le gène Slc4a1 codant pour l’échangeur d’anion de type 1 (AE1) a été modifié, pour introduire une mutation ponctuelle (R589H) dans la séquence protéique. Cette mutation est la plus fréquente des mutations de cette protéine responsable d’acidose tubulaire rénale distale chez l’Homme. Comme les patients, ces souris présentent une acidose tubulaire distale. Nos résultats ont montré que la diminution de l’activité d’échange Cl-/HCO3-, due à la baisse drastique de l’expression d’AE1 dans les cellules -intercalaires du canal collecteur, affecte l’expression et la distribution apicale de la pompe à protons, ce qui altère de ce fait la fonction d’acidification de l’urine. Le second travail porte sur l’étude de la régulation du transport de chlore par le complexe protéique ClC-Kb/Barttin, par phosphorylation de la Barttin. Ce travail démontre que la phosphorylation de la Barttin stimule le transport de chlore du canal ClC-Kb, en augmentant la distribution et la stabilité du complexe ClC-Kb/Barttin à la membrane. Ainsi, la phosphorylation de la Barttin pourrait représenter un mécanisme d’adaptation du transport de chlore en réponse à des variations des apports alimentaires en NaCl. / Kidney plays a major role in several biological fonctions as sodium balance or acid-base homeostasis. Chloride transport in the distal nephron is a key element of these two processes. During my thesis, i have worked on two projects related to physiology and pathophysiology of chloride transport in distal nephron. The first study is the functionnal and molecular characterization of a mouse model bearing the most common dominant dRTA mutation in human AE1, R589H, which corresponds to R607H in the mouse. R607H knock-in mice display incomplete dRTA. Our results showed that reduced basolateral anion exchange activity in type A intercalated cells inhibits trafficking and regulation of V-type ATPase, compromising luminal H+ secretion. In the second study, we investigated the role of a phosphorylation site in the regulation of chloride transport by the ClC-Kb/Barttin channels complex. Our results indicates that Barttin phosphorylation stimulates chloride transport by ClC-Kb channels by increasing the number of active channels in the membrane and hence are involved in the mechanisms of adaptation of renal chloride absorption in response to changes in dietary NaCl intake.
265

Pure-injective modules over tubular algebras and string algebras

Harland, Richard James January 2011 (has links)
We show that, for any tubular algebra, the lattice of pp-definable subgroups of the direct sum of all indecomposable pure-injective modules of slope r has m-dimension 2 if r is rational, and undefined breadth if r is irrational- and hence that there are no superdecomposable pure-injectives of rational slope, but there are superdecomposable pure-injectives of irrational slope, if the underlying field is countable.We determine the pure-injective hull of every direct sum string module over a string algebra. If A is a domestic string algebra such that the width of the lattice of pp-formulas has defined breadth, then classify "almost all" of the pure-injective indecomposable A-modules.
266

Řešení systému chlazení odplynů pro odstranění obsažených rozpouštědel / Solving of off-gas cooling system for removing contained solvents

Blažek, Pavel January 2011 (has links)
Diploma thesis deals with searching of the most appropriate solution of air mass cooling to clear away contained solvents. The solution is based on real and operated pharmaceutical unit. The cooling system is solved as systém of three tubular heat exchangers. In the first heat exchanger the air mass is cooled down by water, in the second by ice-cold water and brine R32 is used for cooling in the third heat exchanger. Heat exchanger system is solved for cooling the air mass which results in condensation of contained solvent – acetone.
267

Návrh nové evoluce trubkového rámu vozidla Formule Student / Formula Student Tubular Frame New Evolution Design

Slimařík, Dušan January 2012 (has links)
Design of new evolution steel welded tubular frame specified for Formula Student series is the main goal of this thesis. In the first instance, type of frame designs is described. Next part of thesis is devote to rules, which must be respected in designing of new evolution of tubular frame. In main part, construction design and calculations of torsional stiffness using MKP analysis are mentioned. Interesting point of this work is located at penultimate part, which deals with preparation of tubular frame production. This is integral part of the construction process at all. Thesis ends with project summary.
268

Rám formulového vozu s návrhem upevňovacích prvků karosérie / Formula Frame Design with Bodywork Fastening Solution

Trněný, Pavel January 2013 (has links)
This masters thesis concernes with design of formula student frame. Part of masters thesis is to a overview of possible solutions. The main criterion in frame design is final torsional stiffness. Another part of frame design is too solution of suspension attachement to frame. In next part of masters thesis is solved bodywork design and it´s fastening to frame. Final part has few informations about frame manufacturing.
269

Trubkový držák lyžiny rally vozu Škoda Fabia Super 2000 / Tubular Skid Holder of Skoda Fabia Super 2000 Rally Car

Ondruch, Marek January 2013 (has links)
This diploma thesis “Tubular Skid Holder of Skoda Fabia Super 2000 Rally Car” is aimed to engineering design of tubular skid holder of rally car Skoda Fabia Super 2000. There is used FEM software for analysis s evaluation of current variant and following variants of engineering design. The most relevant final variant design, which is consistent with asked stiffness and reduction of weight, was chosen based on findings.
270

Morphology of the female reproductive organs of the African lion (Panthera leo)

Hartman, Marthinus Jacobus January 2012 (has links)
The objectivie of this study was to describe the splanchnology and topography of the female reproductive organs of the African lion. The reproductive organs of three embalmed cadavers from three-year-old known aged nulliparous lionesses weighing between 120 kg and 140 kg were studied. Two fresh carcasses from another study were used for some of the topographical photos since these rendered better quality images. The project was approved by the Animal Use and Care Committee and Research Committee of the University of Pretoria (protocol number V038-09). The topography and splanchnology of the reproductive organs were studied and described in situ and after removal. The kidneys were located far caudally in relation to the thirteenth ribs with the left kidney further caudal. The suspensory ligament was very well developed. It originated in a fan-like manner from the dorso-lateral abdominal wall lateral to the kidney extending up to a few centimetres cranial to the kidney. The proper ligament of the ovary was well developed and consisted of several clearly distinguishable bands. The broad ligament resembled that of the cat with the exeption of the cranial part of the mesovarium being very well developed. The round ligament was well developed and inserted on the medial femoral fascia. It therefore did not extend to the vulva as in other canine and feline species. The left ovary was longer, wider and heavier than its right counterpart and the ovaries were relatively small in relation to body weight. The ovarian bursa had a short mesosalpinx that did not cover any part of the ovary and the fimbriae extended the entire length of the ovary. The urethral tuberculum as well as the urethral crest was very well developed. The left uterine horn was longer than the right and the tip of the uterine horn was located dorsal to the proper ligament. The uterine tube was prominently convoluted, situated entirely on the lateral aspect of the ovary and was found to open directly into the tip of the uterine horn and not onto a papilla. The female reproductive organs of the African lion resemble that of the domestic cat and dog with some major differences especially to the size and development of certain structures. The clinical relevance of these differences has to be debated and some thoughts might include the following: 1) does the suspensory and proper ligaments of the gravid uterus contract to suspend the entire uterus closer to the body wall during hunting since the lioness is the primary hunter in the pride? 2) does the lioness have to roll on her back and extend her back legs after mating to facilitate sperm entering the dorsally located tip of the uterine horn while the round ligament stabilises the terminal part of the uterine horn, and does this have a bearing on the fact that multiple copulations are required over a prolonged period for conception by lions? 3) do more ovulations take place from the bigger left ovary and? 4) are more conceptusses borne by the longer left uterine horn? The anatomical information obtained during this study was subsequently applied in a surgical study on sixteen lionesses using laparoscopy to perform laparoscopic ovariectomy and salpingectomy. The availability of these two laparoscopic procedures subsequently led to a wider interest to its application in population control of lions in the smaller national parks of South Africa. / Dissertation (MMedVet)--University of Pretoria, 2012. / gm2014 / Companion Animal Clinical Studies / unrestricted

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