• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 30
  • 8
  • 5
  • 5
  • 4
  • 4
  • 1
  • 1
  • Tagged with
  • 73
  • 13
  • 8
  • 8
  • 7
  • 6
  • 6
  • 5
  • 5
  • 5
  • 5
  • 5
  • 5
  • 5
  • 4
  • 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.
21

Vem, hur, vad och varför? : En narratologisk analys av Stephen Kings skräckroman Dimman

Andersson, Sofia January 2016 (has links)
This essays content is about a narratological analysis of “The Mist”, written by Stephen King, with a focus on who, how, and what in relationship with the story. It also contains a deeper analysis on chosen characters and the meaning behind them. The analysis also takes a look on why King has chosen to use them and their specific details. By mainly using Shlomith Rimmon-Kenan and Jimmy Vulovic I manage to find the voice of the story, how it’s told and what it contains. There is a deeper meaning behind the details that King has selected for his story, for example the colors is not randomly chosen but have a point and a deeper sense behind them. The characters all have a meaning, big and small. The three main characters becomes pillars of the story where they give it and eachother balance with the ir significant roles as hero, villain and helper. It also turns out that the extraterrestrial beings are not the biggest threat of the story, the humans are.
22

Hranice vyprávění: Poslední mlha - lyrický román Maríi Luisy Bombalové / The limits of narrative: La última niebla - lyrical novel by María Luisa Bombal

Bahnerová, Helena January 2011 (has links)
This work focuses on finding instruments which confer a lyrical character to the novel La última niebla of the Chilean writer María Luisa Bombal. The study is based on Emil Staiger's observations about basics concepts of poetic. Specifically, the work treats his concept of lyricism. B asically, the Swiss literary theorist underscored the role of the author, which must necesarilly cancel a distance between himself and his creation in order to achieve lyrical tone. All in all, this and other informations about the lyrical prose of the 20th century prove that lyricism depends especially on the representation of the entity of narrator. María Luisa Bombal as a cosmopolitan writer managed with her production to introduce new style of writing in backward Chilean literary scene. Obvisouly, the p resence of innovative elements such as a utilization of dream poetic or natural symbology takes part in final lyrical tone of the novel La última niebla, however, the most essential renovations within her production are the specific concept of narrator and narrative perspective.
23

Trvání padajících srážek, mlhy a kouřma jako faktor ovlinňující dobu prázdnin / Duration of faling precipitations, fog and mist as factor influencing the timing of vacances

Kothan, Filip January 2013 (has links)
The aim of this paper is to determine suitable term of summer holidays. It should be as long as current holidays in Czech republic, it means 62 days. The paper builds on the bachelor's thesis titled "Optimal timing of summer vacances with regard to climate". The convenient term has been evaluated on basis of characteristics of air temperature, duration of sunshine and the length of day there in the bachelor's thesis. This paper contains the analysis of duration of rain, showers, drizzle, fog and mist. Thus, several terms have been found in both papers. But these are suitable with regard to only one meteorological element or phenomenon. The summer holidays should undoubtedly provide days with the best possible values of more meteorological elements. So the final term was calculated as mean and weighted mean of several dates of the beginning of holidays with the highest values of daily average air temperature, length of day and with the shortest total duration of the complex of rain, showers and drizzle and the complex of fog and mist. The weights of individual elements have been determined in two ways, so we have obtained three terms of holidays: two as result of the weighted mean and one as result of the mean. The best periods for holidays, determined by the weighted mean, are 11th June - 11th...
24

Towards automating micropropagation: from cells to shoots to plants in one step

Fei, Liwen 27 April 2015 (has links)
A mist reactor was used to study plant growth and development under various environmental conditions towards the production of healthy plantlets ready for soil transplant in one step from inoculation. In addition, a 3D type of cultivation via surface attachment of explants to vertically hanging strips inside the mist reactor was also investigated to maximize productivity with minimal footprint. Using carrot as the model species, pre-embryogenic cell suspensions were successfully spray-inoculated onto hanging poly-L-lysine (PLL)-coated nylon mesh to which they then attached and remained for several weeks while they developed into rooted plantlets. To study single step micropropagation from shoot explants to fully acclimatized plantlets, Artemisia annua was used as the model species. Nodal cuttings of A. annua were inoculated onto PLL-coated mesh strips by briefly immersing the strips in the suspension of nodal cuttings. Investigation of medium, phytohormones, CO2, ventilation level and humidity ensued resulting in selection of a preferred final process that reduced physiological aberrations like hyperhydricity and was time efficient. The nodal cuttings that attached to the strips were first misted with half strength shooting medium for 7 days to develop new shoots. Then the new shoots were misted with the rooting medium supplemented with NAA for 12 days to develop roots. Rooted plantlets were acclimatized in the same rooting medium for 9 days to acquire fully functional stomata prior to planting into soil. Taken together this study suggested that fully developed plantlets ready for planting into soil could be obtained in a single step in a bioreactor from embryogenic cells or from nodal explants.
25

An Assessment of Moisture Induced Damage in Asphalt Pavements

Htet, Yar Zar Moe 29 April 2015 (has links)
Moisture-induced damage is one the major causes of deterioration of asphalt pavements and extensive research has been conducted on this topic. Theoretical and experimental results have led the researchers to believe that moisture-induced damages are caused mainly by the generation of pore water pressure in asphalt mixtures when traffic passes over a pavement. The Moisture Induced Sensitivity Tester (MIST) has been recently developed to simulate the phenomenon of repeated pore pressure generation and deterioration in the laboratory. The objective of this study was to evaluate moisture-induced damage in typical Maine Department of Transportation (DOT) asphalt mixes, with the use of MIST, pre and post testing, and analysis of data. The MIST was used to condition Hot Mix Asphalt (HMA) samples that were compacted from eight typical Maine DOT mixes, with different types of aggregates and asphalt binder. A modified Dynamic modulus test in Indirect Tensile Mode was used for the determination of damage. A layered elastic model, along with a fatigue-cracking criterion, was utilized to assess the total impact on the pavement lives. Monte Carlo analysis was conducted to determine the distribution of number of repetitions to failure of pavements that are subjected to moisture damage. The major conclusions are that most of the mixes are likely to experience a reduction in their life due to the effect of moisture and that the Micro-Deval and the fine aggregate absorption test results can be related to such damage. A composite factor, consisting of both of these test results, is recommended for regular use by the DOT to screen mixes with high moisture damage potential.
26

Avifauna em fragmentos de Mata Atl?ntica, Pira?, RJ / Avifauna in Atlantic Rainforest fragments, Pira?, RJ

SILVA, Tatiane Lima da 02 March 2018 (has links)
Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2018-11-12T20:44:46Z No. of bitstreams: 1 2018 - Tatiane Lima da Silva.pdf: 3356978 bytes, checksum: 814f934a7b82c576f5248ee783fb8c66 (MD5) / Made available in DSpace on 2018-11-12T20:44:46Z (GMT). No. of bitstreams: 1 2018 - Tatiane Lima da Silva.pdf: 3356978 bytes, checksum: 814f934a7b82c576f5248ee783fb8c66 (MD5) Previous issue date: 2018-03-02 / CAPES / The Atlantic Rainforest is currently one of the most threatened biomes, considered global priority of conservation. Most of its forest remnants are in the form of small fragments. Forest fragmentation processes can lead to negative consequences for avifauna, such as the loss of specialized species, and increase in the proportion of opportunistic species. This study aimed to survey birds in forest fragments located in three private properties: Ip? Grange (IG), Monumento Grange (MG) and Fortaleza Farm (FF), located in Cacaria, Pira?, RJ. In the first chapter, a comparison was performed for the bird communities of the three sites regarding richness, frequency of occurrence, composition, abundance, diversity, equability and trophic guilds. In the second chapter, the biology of birds captured in mist networks in terms of capture and effort rate, seasonality, morphometric variation, body mass, feather molting and incubation plate were analyzed. The mist nets survey was conducted between August 2015 and February 2017, in which ten mist nets were opened from 06:00 a.m. to 17:00 p.m. Eight, eleven and nine field days were dispensed in SI, SM and FF, respectively. Four points counts were sampled in each fragment monthly between May 2016 and April 2017. A total of 205 species were recorded, with FF displaying the highest richness (147 sp) and the second highest diversity (H' = 4.38), MG displayed the second highest richness (130 sp) and the highest diversity (H' = 4.42), followed by IG, with the lowest wealth (122 sp) and diversity (H' = 4.26). Species composition varied significantly among the three sampled areas (F = 5,15; p = 0,0002), with each site presenting a different composition in relation to the others. A predominance of insectivorous and omnivorous species was observed in the three fragments. A total of 252 individuals were captured, distributed between 77 bird species. The dry season presented a higher catch rate (10.5%) when compared to the rainy season (6.6%), revealing a seasonal pattern. The highest body mass was observed for Leptotila rufaxilla (187.4g ? 16.72; n = 7,) and the lowest for Hylocharis cyanus (0.6g; n = 1). Beak length and total length presented the highest and the lowest coefficient of variation, respectively. When analyzing morphometric variations between sexes, in Manacus manacus, only wing, tail and tarsal length were significantly different. Of the total number of captured individuals, 71 (28.3%) displayed a brood patch and 37 (14.6%) were molting. The brood patch and molting were associated with season (?2 = 20.627; p = 0.000005 and ?2 = 8.363; p = 0.0038, respectively). In 16 individuals (6.34%), a molt and brood patch overlap was found, with molt associated with the brood patch (?2 = 4.408; p = 0.035). Although the study area was represented by small forest fragments with a certain degree of environmental impact, a significant local diversity was found, with the presence of endemic and endangered species. / A Mata Atl?ntica ? um dos biomas mais amea?ados atualmente e considerada como prioridade mundial de conserva??o. A maior parte de seus remanescentes florestais encontra-se na forma de pequenos fragmentos. O processo de fragmenta??o florestal pode trazer consequ?ncias negativas para a avifauna, como a perda de esp?cies especializadas e aumento de esp?cies oportunistas. Este trabalho teve como objetivo o levantamento de aves em fragmentos florestais localizados em tr?s propriedades particulares: o S?tio Ip? (SI), o S?tio Monumento (SM) e a Fazenda Fortaleza (FF), situados em Cacaria, Pira?, RJ. No primeiro cap?tulo foi realizado uma compara??o da comunidade de aves entre estes tr?s locais quanto a riqueza, frequ?ncia de ocorr?ncia, composi??o, abund?ncia, diversidade, equabilidade e guildas tr?ficas. No segundo cap?tulo, foram analisados aspectos da biologia das aves capturadas em redes de neblina quanto a taxa e esfor?o de captura, sazonalidade, varia??o morfom?trica, massa corporal, muda de penas e placa de incuba??o. O levantamento por redes foi realizado entre agosto/2015 a fevereiro/2017, na qual dez redes de neblina foram abertas das 06:00h ?s 17:00h. Foram dispensados oito, 11 e nove dias em campo no SI, SM e FF, repectivamente. Quatro pontos de escuta foram amostrados em cada fragmento mesalmente, entre maio/ 2016 a abril/2017. Foram registradas 205 esp?cies, na qual a FF foi local com a maior riqueza (147 sp) e a segunda maior diversidade (H?= 4,38). O SM apresentou a segunda maior riqueza (130 sp) e a maior diversidade (H?= 4,42). J? o SI demonstrou a menor riqueza (122 sp) e diversidade (H? = 4,26). A composi??o de esp?cies variou significativamente entre as tr?s ?reas amostradas (F = 5,15; p = 0,0002), na qual cada local apresentou uma composi??o diferente em rela??o aos demais. Houve predomin?ncia de esp?cies inset?voras e on?voras nos tr?s fragmentos. Foram capturados 252 indiv?duos distribu?dos em 77 esp?cies de aves. A esta??o seca apresentou maior taxa de captura (10,5%) quando comparada ? esta??o chuvosa (6,6%), revelando um padr?o sazonal. A maior massa corp?rea foi encontrada em Leptotila rufaxilla (187,4g ? 16,72; n = 7) e a menor em Hylocharis cyanus (0,6g; n = 1). O comprimento do bico e comprimento total apresentaram o maior e o menor coeficiente de varia??o, respectivamente. Na an?lise de varia??o morfom?trica entre sexos em Manacus manacus, apenas o comprimento da asa, da cauda e do tarso apresentaram diferen?as significativas. Do total de indiv?duos capturados, 71 (28,3%) apresentaram placa de incuba??o e 37 (14,6%) estavam com muda de penas. A placa de incuba??o e a muda foram associadas ? esta??o do ano (?2 = 20,627; p = 0,000005 e ?2 = 8,363; p = 0,0038, respectivamente). Em 16 indiv?duos (6,34%) foi encontrado sobreposi??o da muda e placa, estando a muda associada a placa de incuba??o (?2 = 4,408; p = 0,035). Apesar da ?rea de estudo ser representada por pequenos fragmentos florestais com um certo grau de impacto ambiental, foi encontrado uma significativa diversidade local, com a presen?a de esp?cies end?micas e amea?adas.
27

Comparing avifauna communities and bird functional diversity of forest and farmland in southwest Ethiopia

Engelen, Dries January 2012 (has links)
Worldwide degradation and conversion of tropical forests affects many species and their provided ecosystem services. Among them are birds, responsible for pollination, seed dispersal, pest control and scavenging. This study, conducted in southwest Ethiopia, compares species composition and bird functional diversity between forest and homegardens close to and far from forest, both in terms of species numbers and bird abundances. Point counts and mist netting were used to obtain data. While the former method detected more species, abundance data from the latter revealed patterns not observed by just comparing species numbers. I found that species diversity was lower in forest compared to gardens and that the species composition of both communities was significantly distinct. Whereas forest had more forest specialists, gardens held more forest visitors and species of open country. Close and far gardens did not differ in any aspect, except that abundances of forest generalist birds were somewhat higher close to forest. Regarding bird feeding guilds, I found that granivores and nectarivores were more numerous in gardens, while frugivores were more common in forest. Carnivores and omnivores showed no effect. Insectivore proportions were the same for forest and farmland, but their numbers (including those of all sub-guilds) were higher in gardens. The Ethiopian forest avifauna is poor in comparison with other Afromontane regions, lacking several, mostly insectivorous genera. This could be the result of an extinction after which its geographic isolation made recolonization difficult, especially for dispersal-limited understory species. Nonetheless, and despite their impoverished state, the results suggest that forest remnants are important for forest-dependent species, being a stronghold for forest specialists and supporting higher numbers of forest generalists in nearby gardens. However, future forest regrowth might be at stake with ongoing agricultural encroachment, because gardens hold fewer frugivores, especially forest specialists, which might affect seed dispersal. / Många arter påverkas negativt av avskogning och annan mänsklig påverkan på tropiska skogar, vilket också kan få konsekvenser för de ekosystemtjänster dessa arter levererar. En viktig artgrupp i detta avseende är fåglar, som kan ha betydelse för pollination, fröspridning, naturlig skadedjurskontroll och som asätare. Denna studie, utförd i sydvästra Etiopien, jämför artsammansättning och funktionell diversitet hos fåglar i skogar och trädgårdar både nära och långt ifrån skogen. Både antal arter och antal individer har undersökts. Data materialet bygger både på observationer från punktinventering och fåglar fångade med slöjnät. Med den första metoden noterade jag fler arter, medan abundansvärden från den andra metoden gjorde att jag såg mönster som inte syntes vid endast jämförelser av artrikedom. Jag fann att artrikedomen var lägre i skogen i jämförelse med trädgårdarna, men att artsammansättningen var signifikant skiljd däremellan. Skogarna hade fler skogsspecialister medan trädgårdarna hade fler arter från öppna marker och tillfälliga skogsbesökande arter. Trädgårdar som låg nära eller långt ifrån skogen skiljde sig inte på något sätt utom att individtätheten av skogsgeneralister var något högre i trädgårdar nära skogen. När det gäller uppdelningen av fåglarna utifrån vad de äter så fann jag att fröätande och nektarätande arter var vanligare i trädgårdar medan fruktätande arter var vanligare i skogen. Rovfåglar och allätare uppvisade inget tydligt mönster. Proportionen insektsätande fåglelarter var samma i skogen och trädgårdarna, men det absoluta antalet arter (inklusive alla olika underkategorier) var högre i trädgårdarna. Den etiopiska skogsfågelfaunan är artfattig i förhållande till andra bergstrakter i Afrika och saknar flera släkten av framförallt insektsätande fåglar. Detta skulle kunna bero på ett tidigare utdöende varefter en senare återkolonisering varit svår på grund av den geografiska isoleringen, speciellt för insektsätande fåglar som huvudsakligen finns i undervegetationen. Trots den relativa artfattigdomen så visar resultatet från min studie hursomhelst på att skogarna är viktiga för skogsberoende fåglar. Den största betydelsen har de för skogsspecialister där, men även genom en positiv effekt på abundansen av skogsgeneralister i närliggande trädgårdar. Dock kan framtida återväxt av skogar bli problematisk på grund av en pågående omvandling av skogar till trädgårdar, eftersom trädgårdar hyser färre fruktätande fåglar, vilket kan påverka fröspridning över landskapet. / Examining mismatches between management and the supply of ecosystem services in Ethiopian agroecosystems across scales in space and time
28

Modelling of Tool Life and Micro-Mist flow for Effective Micromachining of 316L Stainless Steel.

Kajaria, Saurabh 2009 December 1900 (has links)
Recent technoligical advancement demands new robust micro-components made out of engineering materials. The prevalent methods of manufacturing at micro-nano level are established mostly for silicon structures. Therefore, there is interest to develop technologies for micro-fabrication of non silicon materials. This research studies microend-milling of 316L stainless steel. Machine tool requirement, tool modeling, cutting fluid evaluation, and effect of cutting parameters are investigated. A machine tool with high rigidity, high spindle speed, and minimal runout is selected for successful micro-milling. Cumulative tool wear and tool life of these micro-tools are studied under various cutting conditions. Ideal abrasive wear is observed when applying mist cooling whereas inter-granular shearing is the major failure mode while flood cooling or dry cutting during micro-machining. Various experiments and computational studies suggest an optimal position of the mist nozzle with respect to a tool that provides maximum lubrication at the cutting edge. Mist droplets effectively penetrate the boundary layer of a rotating tool and wet the cutting edge and significantly improve the tool life.
29

Alumina Nanofluid for Spray Cooling Heat Transfer Enhancement

Bansal, Aditya 23 March 2007 (has links)
Nanofluids have been demonstrated to be promising for heat transfer enhancement in forced convection and boiling applications. The addition of carbon, copper, and other high-thermal-conductivity material nanoparticles to water, oil, ethylene glycol, and other fluids has been determined to increase the thermal conductivities of these fluids. The increased effective thermal conductivities of these fluids enhance their abilities to dissipate heat in such applications. The use of nanofluids for spray cooling is an extension of the application of nanofluids for enhancement of heat dissipation. In this investigation, experiments were performed to determine the level of heat transfer enhancement with the addition of alumina nanoparticles to the fluid. Using mass percentages of up to 0.5% alumina nanoparticles suspended in water, heat fluxes and surface temperatures were measured and compare. Compressed nitrogen was used to provide constant spray nozzle pressures to produce full-cone sprays in an open loop spray cooling system. The range of heat fluxes measured were for single-phase and phase-change spray cooling regimes.
30

Etude expérimentale et numérique des rideaux d'eau pour la protection contre le rayonnement thermique / Experimental and numerical study of water curtains used as radiative shields

Lechêne, Sullivan 13 July 2010 (has links)
Les rideaux d'eau sont des milieux semi-transparents constitués de gouttelettes d'eau dispersées dans l'air. Le but de ces rideaux ici n’est pas d’interagir avec la flamme dans une optique d’extinction mais plutôt d’agir en tant que boucliers radiatifs contre une forte source de chaleur. En effet, placés entre une source radiative et une cible à protéger, ils permettent de limiter la propagation du rayonnement grâce notamment au caractère absorbant et diffusant des gouttelettes d’eau. L’intérêt du brouillard d’eau réside dans la présence de fines gouttelettes d'eau. Elles possèdent, à quantité d'eau égale, une capacité d'atténuation du rayonnement largement supérieure à celle des techniques de « sprinklage », utilisant une quantité d’eau abondante constituée de gouttes de gros diamètres. Nous avons travaillé expérimentalement (réalisation d'un pilote) et numériquement (code BERGAMOTE) sur le rôle des conditions d'injection : pulvérisation descendante, ascendante, impactante, jets mutualisés en rampe (avec des systèmes comprenant une seule rampe ou deux rampes associées), etc... pour quantifier et comprendre les phénomènes mis en jeu. On retiendra en particulier le fort couplage entre la dynamique des brouillards ou rideaux d'eau et leur propriété d'écran thermique. Il résulte également de ces travaux qu’une modification de la direction d’injection, tout en conservant la même quantité d’eau injectée, engendre de fortes variations sur la capacité d’atténuation du rideau, s’expliquant par la dynamique des sprays injectés. La taille et la concentration en gouttelettes d’eau (liée au temps de séjour des gouttes dans le domaine) apparaissent alors comme des paramètres cruciaux dans l’optique d’une optimisation de ces systèmes de protection / Water sprays, water curtains, or mists, are semi-transparent media made of droplets dispersed in air. Here, water sprays are not used for the extinction of the flame but for radiative shielding against infrared radiation coming from a hot surface. Indeed, placed between a radiative source and a target to be protected, they are able to limit the radiation propagation, due in particular to the ability of droplets to absorb and to scatter infrared radiation.The advantage of mists consists in the presence of fine water droplets. In fact, with the same water volume, they have a widely superior capacity of attenuation radiation compared to “sprinkler” systems which use much water involved as large droplets. A study has been carried out both experimentally (design of an experimental setup) and numerically (BERGAMOTE code) in order to better understand the role of injection conditions. Therefore downward pulverization, upward pulverization, “impinging” spray, several nozzles in a ramp (with systems including one ramp or two ramps), etc… were investigated in order to quantify and assess the implicated phenomena. In particular, a strong coupling appears between the dynamics of sprays and their property of thermal shield. It was also observed from these works that a modification of injection direction, while conserving the same quantity of injected water, results in a strong variation on the attenuation capacity of water curtain, explained by the dynamics of injected sprays. It is worth noting that diameter and concentration of water droplets (related to the residence time of droplets in the domain) are crucial parameters when optimizing these protection systems

Page generated in 0.3444 seconds