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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.
321

Human eosinophils and their activation by allergens via danger receptors

Redvall, Elin, January 2010 (has links)
Diss. (sammanfattning) Göteborg : Univ. , 2010.
322

Aspects of regional planning & rural development affected by factors of physical environment dust storms and desert creep : a case study suggesting various remedies to the ecological degradation affecting the eastern Sudan /

Tewfik, Magdy, January 1900 (has links)
Thesis--Lund. / Bibliography: p. 221-228.
323

Microwave observations of the Southern sky from the TopHat experiment : the cosmic microwave background and the Magellanic clouds /

Bezaire, Jeffery J. January 2003 (has links)
Thesis (Ph. D.)--University of Chicago, Dept. of Physics, June 2003. / Includes bibliographical references. Also available on the Internet.
324

Aerosol scattering phase function retrieval from polar orbiting satellites /

Wunder, Daniel P. January 2005 (has links) (PDF)
Thesis (M.S. in Meteorology)--Naval Postgraduate School, March 2005. / Thesis Advisor(s): Philip A. Durkee. Includes bibliographical references (p. 77-78). Also available online.
325

Nitrogen, phosphorus and particulate matter budgets of five coniferous forest ecosystems in the western Cascades Range, Oregon /

Fredriksen, R. L. January 1975 (has links)
Thesis--Oregon State University. / Bibliography: p. 117-122. Also available on the World Wide Web.
326

Predictors of indoor dust mite and cockroach levels

Brooks, J. Mark. January 2007 (has links) (PDF)
Thesis (Ph. D.)--University of Alabama at Birmingham, 2007. / Title from first page of PDF file (viewed June 30, 2007). Includes bibliographical references (p. 94-101).
327

Detecção automática de rastros de Dust Devils na superfície de Marte

Statella, Thiago [UNESP] 17 May 2012 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:30:31Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-05-17Bitstream added on 2014-06-13T18:40:48Z : No. of bitstreams: 1 statella_t_dr_prud.pdf: 3750237 bytes, checksum: 5e7d05a021f74eef1040300825e464e5 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Dust Devils são vórtices convectivos formados por correntes de ar quente instáveis, próximas à superfície planetária. Inúmeros pesquisadores têm estudado dust devils marcianos na tentativa de melhor entender o fenômeno. Em geral, as áreas de pesquisa compreendem a simulação numérica e mecânica de dust devils em laboratório, metodologias para reconhecimento de vórtices por robôs pousados na superfície de Marte e a detecção de vórtices e rastros em imagens orbitais. A despeito do grande número de artigos relacionados ao assunto, nenhum deles aborda a detecção automática de rastros de dust devils, tarefa que ganha especial importância quando a quantidade de imagens da superfície de Marte cresce a uma taxa maior que a capacidade humana de analisá-las em um curto período de tempo. Esta Tese descreve um método inédito para detecção automática de rastros de dust devils. O banco de imagens utilizado contém 200 imagens (90 MOC e 110 HiRISE), distribuídas pelas regiões Aeolis, Noachis, Argyre, Eridania e Hellas. O método é fortemente baseado na Morfologia Matemática e usa transformações como abertura e fechamento por área morfológicos, fechamento por caminho morfológico, método de Otsu... / Dust devils are vortices caused by unstable wind convection processes near the planetary surfaces, due to solar heat. Many researchers have being studying Martian dust devils in an attempt to better understand the phenomena. Generally, the research fields comprise mechanic and numerical simulation of dust devils in laboratories, methodologies for recognition of dust devils plumes from rovers on Mars surface, detection of plumes and tracks from orbital images. Despite the number of papers regarding the subject, none of them addresses the automatic detection of dust devil tracks which is an important issue as the amount of images taken grows at a rate greater than the human capability to analyze them. This Thesis describes a novel method to detect Martian dust devil tracks automatically. The dataset comprises 200 images (90 MOC and 110 HiRISE), distributed over the regions of Aeolis, Noachis, Argyre, Eridania and Hellas. The method is strongly based on Mathematical Morphology and uses transformations such as morphological surface area closing and opening, morphological path closing and Otsu's method for automatic image binarization, among others. The method was applied to the dataset and results were compared... (Complete abstract click electronic access below)
328

Active Dust Devils on Mars: A Comparison of Six Spacecraft Landing Sites

January 2011 (has links)
abstract: Dust devils have proven to be commonplace on Mars, although their occurrence is unevenly distributed across the surface. They were imaged or inferred by all six successful landed spacecraft: the Viking 1 and 2 Landers (VL-1 and VL-2), Mars Pathfinder Lander, the Mars Exploration Rovers Spirit and Opportunity, and the Phoenix Mars Lander. Comparisons of dust devil parameters were based on results from optical and meteorological (MET) detection campaigns. Spatial variations were determined based on comparisons of their frequency, morphology, and behavior. The Spirit data spanning three consecutive martian years is used as the basis of comparison because it is the most extensive on this topic. Average diameters were between 8 and 115 m for all observed or detected dust devils. The average horizontal speed for all of the studies was roughly 5 m/s. At each site dust devil densities peaked between 09:00 and 17:00 LTST during the spring and summer seasons supporting insolation-driven convection as the primary formation mechanism. Seasonal number frequency averaged ~1 dust devils/ km2/sol and spanned a total of three orders of magnitude. Extrapolated number frequencies determined for optical campaigns at the Pathfinder and Spirit sites accounted for temporal and spatial inconsistencies and averaged ~19 dust devils/km2/sol. Dust fluxes calculated from Pathfinder data (5x10-4 kg/m2/s and 7x10-5 kg/m2/s) were well with in the ranges calculated from Spirit data (4.0x10-9 to 4.6x10-4 kg/m2/s for Season One, 5.2x10-7 to 6.2x10-5 kg/m2/s during Season Two, and 1.5x10-7 to 1.6x10-4 kg/m2/s during Season Three). Based on the results a campaign is written for improvements in dust devil detection at the Mars Science Laboratory's (MSL) site. Of the four remaining candidate MSL sites, the dusty plains of Gale crater may potentially be the site with the highest probability of dust devil activity. / Dissertation/Thesis / M.S. Geological Sciences 2011
329

Emise tuhých znečišťujících látek v chovu drůbeže

JANOUŠEK, Tomáš January 2016 (has links)
Agricultural activities produce a number of dangerous wastes affecting the environment. One is powder produced in livestock production, in particular in stables factory farms. Particulate emissions from livestock buildings are particularly important for the closest neighborhood stables. It is the subject of conflicts between farmers and their neighbors. The source of dust in livestock buildings are mainly food (fine particles modified cereals and dried plants) renegade animal skin particles, urine crystals and particles of feces. The aim of this work is to determine the concentration of dust in the factory farming of chickens for meat. Secondly, the aim is to compare BAT (Best Available Technique - Best Available Technology) technology used in stables with the reference document BREF (Integrated Pollution Prevention and Control - Integrated Pollution Prevention and Control). Measurements were carried out on a Farma U lesa in Sudoměřice u Bechyně on a poultry farm in Horní Miletín.
330

Sklízecí mlátičky z hlediska hlučnosti a prašnosti

LÍKAŘ, Ondřej January 2016 (has links)
The thesis is focused on the combine harvester in terms of noise and dust in the cabin, but also outside. The literature search is the basic data and concepts from areas combine harvesters, noise and dust. The actual measurements were carried out on the land at the four farmers. Measured the machines were different dates of manufacture. These are machines Fortschritt E 512 (1983), Fortschritt E 514 (1989), IH 2188 (1998) and Claas Avero 240 (2011). The results of measurement were graphically displayed and compared each other. The measured values were compared with the current legislation. These measurements showed that the noise does not just limit oldest machine. Dustiness been in this job for guidance only. Thanks dust measurements but we get a more complete view of the work environment in which the operator is exposed.

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