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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.
31

Red-Tailed Hawk Home Range, Habitat Use, and Activity Patterns in North-Central Puerto Rico

Llerandi-Roman, Ivan C 13 May 2006 (has links)
I determined abundance, movement and activity patterns of the Red-tailed Hawk (Buteo jamaicensis jamaicensis, RTHA) in Río Abajo Forest, Puerto Rico and surrounding lands during 2003-2004. Captive-reared Puerto Rican Parrots (Amazona vittata, PRPA) are scheduled for release in Rio Abajo Forest in 2006. Annual density of RTHAs (0.90 RTHAs/km2) was similar to the Caribbean National Forest (CNF; 1.29 RTHAs/ km2). RTHAs annual survival was high (0.89), and birds maintained compressed territories around the Rio Abajo Forest. Home ranges were 91% smaller than estimates reported for CNF, yet similar to those in North America. Approximately 98.3% of RTHA locations occurred outside the Río Abajo Forest boundaries. RTHAs exhibited random macrohabitat use patterns in north-central Puerto Rico. However, within their home ranges, RTHAs selected fragmented habitats with high patch and edge density, and avoided large tracts of dense closed canopy forest. Encounters between RTHAs and PRPAs may increase as parrots venture beyond the boundaries of Rio Abajo Forest.
32

[en] STUDY OF HIGH-SPEED STEELS OXIDATION UNDER DRY AND MOIST AIR ENVIRONMENTS AND UNDER CYCLIC OXIDATION CONDITION / [pt] ESTUDO DA OXIDAÇÃO DE AÇOS RÁPIDOS EM ATMOSFERA DE AR SECO E ÚMIDO E EM CONDIÇÃO DE CICLAGEM TÉRMICA

MAURICIO DE JESUS MONTEIRO 04 April 2005 (has links)
[pt] O desenvolvimento e a utilização de aços rápidos para a produção da casca externa de cilindros destinados à laminação de tiras a quente tiveram início no começo dos anos 90. A introdução deste material melhorou, significativamente, a resistência ao desgaste do cilindro, a qualidade da tira laminada e a duração da campanha de laminação. Representou, desta forma, o maior avanço tecnológico recentemente obtido no campo da laminação a quente. Entretanto, foi observado que o desprendimento da camada de óxido nestes aços possuía características diferentes daquelas obtidas nos cilindros de laminação convencionais. Este fenômeno foi atribuído ao processo de oxidação dos aços rápidos, que é cerca de quatro vezes maior do que o das ligas anteriormente utilizadas. Para que todo o potencial dos cilindros de laminação a quente, fabricados com este material, seja alcançado, torna-se necessário, portanto, o estudo da oxidação de aços rápidos. A presente tese estudou a oxidação de quatro composições químicas de aços rápidos. Foram realizados ensaios de termogravimetria em atmosfera de ar seco e úmido (12,5% H2O) assim como ciclagem térmica com resfriamento em água. Um aparelho de produção e controle de umidade e um mecanismo de ciclagem térmica foram construídos para este trabalho. As amostras oxidadas foram analisadas por difração de Raios - X, microscopia eletrônica de varredura e espectroscopia de dispersão de energia. A discussão dos resultados avaliou o efeito da composição química, da umidade e da ciclagem térmica no comportamento dos aços rápidos estudados quanto à oxidação. Como conclusões, verificou-se que o teor de cromo possui influência no ganho final de massa, que um teor elevado de molibdênio pode promover oxidação catastrófica em atmosfera de ar seco e que a variação do teor de tungstênio utilizada não influenciou o comportamento de oxidação. Foi verificado também que a presença de 12,5 % de H2O influenciou significativamente as características de oxidação e que a oxidação em condição de ciclagem térmica promoveu a formação de uma fina camada de óxidos ricos em vanádio na região externa da camada de óxido das amostras estudadas. / [en] Development and use of high-speed steel for manufacturing the roll outer shell of hot strip mills have started in the early 1990s. The introduction of this material has improved, significantly, the roll wear resistance, the surface quality of rolled products and the length of rolling campaign. It has represented, therefore, the major technological breakthrough recently introduced in the hot rolling field. However, it was observed that the oxide layer spalling of these steels had different behavior in comparison with that of conventional rolls. This phenomenon has been attributed to the high-speed steel oxidation, which is about four times higher than the alloys previously used. In order to achieve the full potential of high-speed rolls for hot strip mills, it is necessary, therefore, to study the oxidation behavior of this material. The present thesis studied the oxidation of four different chemical compositions of high-speed steels. Corrosion tests were carried out in a thermobalance under dry and moist (12.5 % H2O) environments. Oxidation under thermal cyclic conditions of specimens cooled in water was also carried out. A cyclic oxidation apparatus and an equipment for humidity production and control were constructed for this work. The corroded samples were examined by X - Ray diffraction, scanning electron microscopy and energy dispersive micro-analysis. The discussion of the results evaluated the effects of humidity, thermal cycling and chemical composition on the oxidation behavior of these high-speed steels. As conclusions, it was verified that the chromium content has influence on the final mass gain, the elevated molybdenum content can produce catastrophic oxidation under dry air environment and that the tungsten content variation did not influence the oxidation behavior. It was also verified that the presence of humidity had a significant effect on the oxidation behavior and that the cyclic oxidation promoted the formation of a thin layer composed of oxides rich in vanadium at the outer region of the scale.
33

Fuktförebyggande åtgärder för ett bättre klimat i den småländska stenkyrkans krypgrund / Moisture preventative actions, in order to ensure a better environment in the crawl space of thestonechurches of Småland

Ekelöf, Henrik, Hasselby, Fabian January 2010 (has links)
Fukt i kyrkans krypgrund är ett ”växande” problem som på senare tid uppmärksammats alltmer. I denna studie har flera möjliga lösningar undersökt, vidare har en allmän angreppsmodell formulerats för att underlätta framtida utredningar. Studien visar bland annat att styrning efter mögelrisken är önskvärt för att få ett energioptimerat och garanterat mögelfritt klimat. Åtgärdsförslag såsom sorptionsavfuktare samt värmning genom elradiator direkt i krypgrunden är möjliga lösningar som med ett litet energitillskott förbättrar klimatet i krypgrunden avsevärt.
34

Komparace ošetřování chronických ran v ambulanci praktického lékaře pro dospělé a ambulanci chirurgie / The comparison of chronic wound treatment in general physician's practice and in surgical outpatient treatment

ŠUPLEROVÁ, Michaela January 2014 (has links)
Current state: The treatment of chronic wounds is a complex process which is applied in the form of different interventions by nurses in the general practitioner's office for adults and nurses from the surgical outpatient clinic. The treatment is influenced by different equipment used in particular offices, by the presence or absence of the interest in implementing modern methods and, of course, by poor participation of health insurance companies as regards the problem in question. The treatment of chronic wounds should be accomplished by completing all the phases of the nursing process. It is necessary to seek for motivation towards further education in this field. Pursuing moist wound healing is mostly cheaper as it makes the treatment shorter, which leads to patient's satisfaction. Objectives: The objective of the thesis was to evaluate the nursing process applied during the treatment of chronic wounds in the general practitioner's office for adults and the surgical outpatient clinic, as well as observe the influence of education on the nurse's professional performance regarding this treatment. The research included the analysis of the competencies of nurses in the treatment of chronic wounds and the treatment methods chosen by the nurses to benefit the patient. Last but not least, we observed the circumstances of the admission of a nurse specialist as a GP's partner for chronic wounds treatment, and the obstacles to moist wound healing implementation in the GP's office for adults and the surgical outpatient clinic. Methods: To compare the treatment of chronic wounds in the general practitioner's office for adults and the surgical outpatient department we carried out qualitative research investigation. Data collection was based on in-depth interview with prepared open questions. The interviews were recorded by voice recorder, transcribed literally and subsequently analysed. When analysing the transcripts, we used the method of open coding, by the technique "pencil and paper". The text of the dialogues was reduced and segmented into individual codes. On the basis of similarity, the codes were classified in analytical units. The categories were classified into schemes by means of SmartArt programme in Microsoft Office Word. The results were interpreted with the use of the open cards technique. The first group of respondents consisted of nurses from a practitioner's office for adults and a private surgical outpatient department. The other group comprised practitioners for adults and surgeons treating outpatients. Research sample: The research sample consisted of 12 respondents from three medical facilities in České Budějovice. In the first set there were three nurses working in the practitioner's office for adults and three nurses working in the surgical outpatient department. The second set comprised three women MDs for adults, two surgeons treating outpatiens and a woman surgeon. The intentional selection was dependent on respondents' willingness to participate in the research and it ceased when the state of theoretical saturation was reached. Results: The research investigation showed that modern moist healing of chronic wounds is mostly implemented in the offices of practitioners rather than in surgical outpatient clinics. The surgical department is aseptic and they want to minimize the risk of possible infection. Apart from moist healing the surgeons use other modern healing methods such as laser biostimulation, biostimulatory polarized light and instrument-aided lymphatic drainage. The education of the nurses involved in chronic wounds treatment is not provided within academic courses. Just two nurses completed university education whereas the other nurses get acquainted with current information at commercial presentations provided by pharmaceutical representatives. These nurses lack the capability of objective assessment of basic and specific parameters of the wounds and of subsequent treatment.
35

Florística e padrões de distribuição da flora associada à áreas úmidas sazonais no Parque Estadual do Ibitipoca, Minas Gerais, Brasil

Cruz, Ludymila Viana Valadares 03 March 2017 (has links)
Submitted by Renata Lopes (renatasil82@gmail.com) on 2017-07-05T19:32:09Z No. of bitstreams: 1 ludymilavianavaladarescruz.pdf: 3523641 bytes, checksum: 53cbc1cd3b45523b858cf731334bd681 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2017-08-08T15:00:51Z (GMT) No. of bitstreams: 1 ludymilavianavaladarescruz.pdf: 3523641 bytes, checksum: 53cbc1cd3b45523b858cf731334bd681 (MD5) / Made available in DSpace on 2017-08-08T15:00:51Z (GMT). No. of bitstreams: 1 ludymilavianavaladarescruz.pdf: 3523641 bytes, checksum: 53cbc1cd3b45523b858cf731334bd681 (MD5) Previous issue date: 2017-03-03 / O Parque Estadual do Ibitipoca (PEIB), inserido na Serra da Mantiqueira, é a menor unidade de conservação do Estado de Minas Gerais com predomínio dos campos rupestres, sendo considerado uma área prioritária para conservação da flora do Estado. Durante a estação chuvosa, formam-se as áreas úmidas, campos úmidos e lagoa temporária, que compreendem uma flora singular, com espécies adaptadas aos solos ricos em matéria orgânica e com grande amplitude hídrica. O objetivo do presente trabalho foi conhecer a riqueza, diversidade, composição, estrutura e distribuição da vegetação associada às áreas úmidas do PEIB. Os resultados são apresentados em dois capítulos. Para o levantamento florístico foram realizadas expedições mensais de abril de 2015 a agosto de 2016. Foram encontradas 81 espécies nos campos úmidos, em sua maioria endêmicas do Brasil, incluídas em 55 gêneros e 21 famílias. Na lagoa temporária foram encontradas 27 espécies, grande parte com ampla distribuição geográfica, pertencentes a 23 gêneros e 11 famílias, sendo uma espécie nova para a ciência e considerada microendêmica. Em ambas as áreas a forma de vida predominante foi hemicriptófita. A composição florística mostrou uma grande importância para conservação com a presença de doze espécies endêmicas de Minas Gerais e cerca de 22% da riqueza específica presente em alguma categoria de ameaça de extinção. Para verificar a diversidade florística e compreender os padrões de distribuição da comunidade vegetal na lagoa temporária (Lagoa Seca) foram realizadas coletas fitossociológicas em novembro de 2015 e fevereiro, abril e junho de 2016. Foram amostrados 24 táxons: quatro briófitas e 20 angiospermas. As espécies anfíbias obtiveram maior predominância, seguida das emergentes. Juncus microcephalus (44,7) e Nymphoides indica (25,5) alcançaram os dois maiores VI’s na comunidade. A diversidade para a área de estudo como um todo foi considerada baixa (H’=1,83) em relação a outros estudos em áreas úmidas, enquanto a equitabilidade foi considerada alta (J=0,88). Não foi possível agrupar espécies preferenciais a ambientes úmidos ou ambientes secos, espacialmente e temporalmente. A umidade do solo medida não possui correlações significativas com as riquezas, sugerindo que a submersão das espécies tenha maior efeito como barreira de colonização. / The Parque Estadual do Ibitipoca (PEIB) is a smaller conservation unit in the state of Minas Gerais with campos rupestres as its main vegetation, being considered a priority area for conservation of the state's flora. Wetlands are formed during the rainy season, and are known as moist grasslands and seasonal pond, comprising a singular flora, with species adapted to organic matter richness of the soil and a great flooding amplitude. The main aim of the study was to know the richness, diversity, composition, structure and distribution of the vegetation of PEIB wetlands. The results are presented in two chapters. For the floristic survey, monthly expeditions were carried out from April 2015 to August 2016. At the moist grasslands were found 81 species, most endemics of Brazil, included in 55 genera and 21 families. At the Lagoa Seca 27 species were found, most with wild distribution, distributed in 23 genera and 11 families. In both wetlands, the hemicryptophytes were the most predominant Raunkiaer's life form. Floristics results showed a great importance for conservation with 22% of species in some threatness category, twelve species endemic to Minas Gerais state and a new Cyperaceae taxa. For the verification of the floristic diversity and for understanding the distribution patterns of plants community at the seasonal pond (Lagoa Seca) phytosociological collections were carried out in November 2015 and February, April and June 2016. Were found 24 species: 4 bryophytes and 20 angiosperms, with predominance of amphibian species, followed by the emergent ones. Juncus microcephalus (44.7) and Nymphoides indica (25.5) reached the two largest VI’s in the community. The values of diversity (H') did not vary temporally or spatially in the area. The diversity for the study area was considered low (H’= 1.83) in relation to other studies in wetlands, as equitability was considered high (J = 0.88). It has not been possible to observe a zonation of preferred species in wet or dry environments, both spatially and temporally. The measured soil moisture does not present a significant correlation with species richness, suggesting that the submersion could have a greater effect as a barrier of colonization.
36

Impact des processus humides sur les dépressions des latitudes tempérées / Impact of moist processes on midlatitude cyclones

Coronel, Benoît 25 November 2015 (has links)
Les objectifs de cette thèse sont d'analyser l'influence des processus humides sur les dépressions des moyennes latitudes en s'intéressant plus particulièrement aux déplacements des dépressions et à la formation des vents forts près de la surface. Ces recherches ont été effectuées à l'aide de simulations idéalisées du modèle de méso-échelle Méso-NH. La première étude s'est focalisée sur l'effet des processus humides sur le déplacement des dépressions dans la direction perpendiculaire à l'axe du courant-jet, c'est à dire principalement le déplacement vers les pôles. Le mécanisme expliquant ce déplacement est dû à l'advection non-linéaire de la dépression de surface par les anomalies cyclonique et anticyclonique d'altitude se trouvant de part et d'autre de la dépression de surface. En présence d'humidité, l'anomalie anticyclonique d'altitude se renforce du fait du dégagement de chaleur latente dans les zones d'ascendances, et ainsi le déplacement perpendiculairement à l'axe du jet et vers les pôles s'accélère. On montre aussi que le déplacement vers l'est des dépressions s'accélère en incluant les processus humides. La seconde étude porte sur la formation des vents forts près de la surface et notamment sur ce qu'on appelle les "sting jets". Les "sting jets" sont des jets dont les masses d'air associées descendent rapidement du milieu de la troposphère au niveau de la tête du nuage jusqu'au sommet de la couche limite et peuvent déclencher des vents dévastateurs en surface. Ceux-ci se forment lorsque le front chaud se déplace à l'arrière de la dépression et qu'une fracture frontale apparaît. Les simulations montrent que, lorsqu'une dépression traverse l'axe du courant-jet de son côté chaud à son côté froid, le retour en arrière du front chaud se produit tandis qu'une dépression naissant côté froid du courant-jet possède un front chaud beaucoup moins actif. Ainsi, la formation d'un " sting jet " n'apparaît que dans le premier cas , moyennant une résolution verticale élevée. C'est la présence d'un forçage géostrophique dans un environnement neutre vis-à-vis de l'instabilité symétrique qui facilite la descente des masses d'air et la formation du " sting jet ". / The objective of this thesis is to analyze the influence of moist processes on mid-latitude cyclones, and specifically the tracks of cyclones and the formation of strong winds near the surface. These researches have been made using idealized simulations of the mesoscale model Méso-NH. The first study focused on the effects of moist processes on the motion perpendicularly to the zonal jet axis, poleward. The main mechanism explaining this motion involves the nonlinear advection of the surface cyclone by the upper-level cyclonic and anticyclonic perturbations located on both sides of the surface cyclone. In the presence of humidity, the upper-level anticyclonic anomaly strengthens due to the latent heat release in the ascent zones, and the poleward motion is reinforced. The eastward motion of the cyclone is also reinforced with the inclusion of moist processes. The second study focuses on the formation of near-surface strong winds which are triggered by the so-called " sting-jets ". These jets correspond to descending air masses from the mid-troposphere near the cloud head down to the top of the boundary layer, and can trigger devastating surface winds. In the case where synoptic perturbations are initialized south of the baroclinic zonal jet, the bent-back warm front phase occurs, whereas when they are initialized on the zonal jet axis, the surface cyclone has a less active warm front. Thus, the formation of a sting-jet only occurs in the first case, and with a high vertical resolution. It is the geostrophic forcing in a globally neutral environment relative to conditional symmetric instability which facilitates the airstreams descent and the formation of the sting-jet.
37

Ytterväggar för nybyggnation av modulhus : Hur påverkar valet av yttervägg installation och kostnader för modulhus

Mohsin, Nooraldeen, Hardi, Bawan January 2017 (has links)
This work aims at identifying and proposing four prefabricated exterior wall elements to a company that will build small prefabricated houses where the house elements are produced in a Micro factory. The four wall elements are as follows: Corner wall units, wall elements with no cut-out for windows and doors, wall elements with cut-out for a window and door and wall elements with cut-out for a door. In this report four different prefabricated outer wall elements have been proposed for small housing project. A comparison study has been made between three different wall solutions (Outer wall solution two has been proposed by the students themselves as well as outer wall solution one and three from two different building suppliers, Isover and Paroc.) to ensure which of these walls fits the best for the four prefabrication element drawings. The main difference between the walls solutions mentioned above is that outer wall solution two has one thick layer of insulation with light beam rails and outer wall solution one and three has massive tree beams in them with separated insulation layers. The advantage of light rails compared to massive rails in outer walls is that the thermal bridges are minimized due to the fact that there are not as much exposed joints in the outer wall with light rails. One more big difference is that the U-value's differ between the three outer-wall solutions. Since the materials are different in the three outer-walls the sound insulation and fire protection characteristics also differ. The sound insulation and fire protection ability depends mainly on the amount of plaster boards and type of insulation in the wall. Outer wall solution two has been chosen for the house project and it will be the head characteristic wall ahead in this report. Outer wall Option Two) was chosen for the project. It was chosen due to following criteria's: low energy needs for active heating, low manufacturing costs, low U-value, low construction weight, good moist resistance, good sound reduction and high fire protection class.
38

Interaktivní grafický software pro výpočty stavů vlhkého vzduchu / The interactive graphical software for calculation of moist air states

Snášel, Pavel January 2010 (has links)
The aim of this thesis is to create an interactive graphical software intended for calculations of states of moist air and marking these states in Molliere’s i-x diagram. The branch of air-conditioning is considered to be the main field of application of this software, so the calculations of basic changes of moist air have been included to this software as well.
39

Characteristics of deep moist convection and rainfall in cut-off lows over South Africa

Muofhe, Tshimbiluni Percy 20 September 2019 (has links)
MENVSC / Department of Geography and Geo-Information Sciences / Out of all rain-producing weather systems, cut-off lows (COLs) are linked with the occurrence of high impact rainfall and in some cases short-lived floods which can last for 24 hours over South Africa. This study examined the characteristics associated with the present occurrence of the severe COL systems over South Africa from 2011 to 2017. The accuracy of the 4.4 km Unified Model (UM) which is currently in use for simulating areas of deep moist convection in South Africa was evaluated. The UM simulated geopotential height at 500 hPa as well as the associated 24 hours precipitation which were compared against the daily fields of geopotential height and 6-hourly precipitation from the European Centre for Medium-Range Weather Forecasts (ECMWF). COL events were categorized and analyzed according to the associated surface circulation patterns at 850 hPa. The seasonal distribution and duration of the systems over northern (10°E-33°E //22°-32°S) and southern (10°E-33°E //32°-35°S) regions of the study area were also analyzed. Results show COL systems shifting with season towards the north eastern parts of the country, with an increased number of events during the austral winter season during the study period. Systems which lasted for long time were observed during the austral winter and spring seasons. The UM tends to simulate areas of heavy precipitation accurately with poor simulation during the initial stages of the systems. The UM provided a more realistic-looking closed geopotential height and rainfall fields for systems which are coupled with a cold front at the surface. Application of the knowledge about the evolution in the characteristics of COL events from this study can improve the operational forecasting of these weather systems over the country. / NRF
40

Systemsimulation eines elektrischen Turboladers für Brennstoffzellenanwendungen unter Berücksichtigung von Kondensationsphänomenen in der Radialturbine

Lück, Sebastian, Wittmann, Tim, Göing, Jan, Bode, Christoph, Friedrichs, Jens 27 May 2022 (has links)
Das Betriebsverhalten eines elektrischen Turboladers zur Bedruckung des Kathodengassystems eines automobilen Brennstoffzellensystems wird unter Berücksichtigung der feuchten Brennstoffzellenabluft untersucht. Basierend auf den Komponentenkennfeldern von Elektromotor, Leistungselektronik, Lagerung und Turbomaschinenkomponenten werden stationäre und transiente Betriebslinien berechnet, anhand derer eine Betriebspunktverschiebung gezeigt wird. Diese kann auf die Einflüsse der Gaszusammensetzung und Kondensation in der Turbine zurückgeführt werden. Anhand von drei stationären Betriebspunkten wird die Zusammensetzung der Verluste innerhalb der Maschine gezeigt. Die Verzögerung wird zudem als kritisches Manöver im transienten Betrieb durch signifikante Abnahme des Pumpgrenzabstands identifiziert. / The performance of an electric turbocharger for the cathode gas supply system of an automotive fuel cell system is investigated considering moist air off gasses. Based on the component performance maps of electric motor, power electronics, bearings and turbomachinery, steady state and transient operating lines are calculated and a shift of operating points is shown. These can be traced back to the influence of gas composition and condensation within the turbine. Based on three operating points, losses inside the machine are characterized. Furthermore, deceleration is identified as the most critical transient operating scenario due to a significant decrease of the surge margin.

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