• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 38
  • 25
  • 10
  • 6
  • 6
  • 4
  • 4
  • 2
  • 1
  • 1
  • 1
  • 1
  • Tagged with
  • 117
  • 15
  • 13
  • 13
  • 12
  • 12
  • 12
  • 12
  • 10
  • 10
  • 10
  • 10
  • 9
  • 9
  • 9
  • 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.
1

A comparative analysis of areal interpolation methods

Hawley, Kevin J. January 2005 (has links)
No description available.
2

Range border formation in the light of dispersal evolution / Die Ausbildung von Verbreitungsgrenzen unter Berücksichtigung der Evolution des Ausbreitungsverhaltens

Kubisch, Alexander January 2012 (has links) (PDF)
Understanding the emergence of species' ranges is one of the most fundamental challenges in ecology. Early on, geographical barriers were identified as obvious natural constraints to the spread of species. However, many range borders occur along gradually changing landscapes, where no sharp barriers are obvious. Mechanistic explanations for this seeming contradiction incorporate environmental gradients that either affect the spatio-temporal variability of conditions or the increasing fragmentation of habitat. Additionally, biological mechanisms like Allee effects (i.e. decreased growth rates at low population sizes or densities), condition-dependent dispersal, and biological interactions with other species have been shown to severely affect the location of range margins. The role of dispersal has been in the focus of many studies dealing with range border formation. Dispersal is known to be highly plastic and evolvable, even over short ecological time-scales. However, only few studies concentrated on the impact of evolving dispersal on range dynamics. This thesis aims at filling this gap. I study the influence of evolving dispersal rates on the persistence of spatially structured populations in environmental gradients and its consequences for the establishment of range borders. More specially I investigate scenarios of range formation in equilibrium, periods of range expansion, and range shifts under global climate change ... / Die Frage nach den Ursachen für die Ausbildung von Verbreitungsgrenzen ist ein zentrales Thema ökologischer Forschung. Dabei wurde die Bedeutung geographischer Barrieren als natürliche Grenzen der Ausbreitung von Populationen früh erkannt. Jedoch findet man oft auch in sich graduell ändernden Landschaften, in denen keine Barrieren zu finden sind, sehr scharfe Verbreitungsgrenzen. Mechanistische Erklärungen hierfür unterscheiden zwischen solchen Umweltgradienten, welche entweder die Variabilität der biotischen und abiotischen Umgebung in Raum und Zeit oder die Fragmentierung von Habitat beeinflussen. Dabei wird die spezifische Lage der Verbreitungsgrenze von weiteren Mechanismen beeinflusst, wie Allee-Effekten (d.h. verringerte Wachstumsraten bei kleiner Populationsgröße oder -dichte), zustands- bzw. kontextabhängigem Dispersal und biologischen Interaktionen. Dispersal, das heißt Ausbreitung im Raum mit potentiellen Konsequenzen für den Genaustausch zwischen Populationen, stand im Fokus vieler Studien, die sich mit der Ausbildung von Verbreitungsgrenzen beschäftigt haben. Es ist bekannt, dass das Ausbreitungsverhalten von Populationen sehr variabel ist und selbst innerhalb kurzer Zeit evolvieren kann. Trotzdem haben sich erst wenige Studien mit den Folgen der Evolution des Ausbreitungsverhaltens für biogeographische Muster befasst. Die vorliegende Dissertation verfolgt das Ziel, diese Lücke zu füllen. Ich untersuche den Einfluss evolvierender Emigrationsraten auf das Überleben von räumlich strukturierten Populationen, sowie dessen Konsequenzen für die Etablierung und Dynamik von Verbreitungsgebieten. Dafür ziehe ich verschiedene Szenarien heran. Diese bilden die Verbreitung von Arten im Gleichgewicht, während Phasen der Expansion des Verbreitungsgebietes, sowie im Kontext des globalen Klimawandels ab ...
3

VOWEL ALTERNATION IN DISYLLABIC REDUPLICATIVES: AN AREAL DIMENSION

Ido, Shinji January 2011 (has links)
No description available.
4

The geology of the Floras Creek area, Curry County, Oregon

Bounds, Jon Dudley 01 January 1982 (has links)
The Floras Creek area, east of the town of Langlois, near the southwest Oregon coast, includes Colebrooke Schist (a klippe of metamorphosed pelitic sediments of Jurassic age), Jurassic Otter Point Formation (a melange complex), and lower the middle Eocene Roseburg and Lookingglass Formations, part of a sandstone-shale sequence occurring more extensively in other areas. The Colebrooke Schist occurs in the south-central part of the area, bounded on the Otter Point and Roseburg. The Lookingglass is exposed as a small (1.5 sq. km) block in the north-north-west part of the area. Two major structural trends are found in the Floras Creek area; an older Mesozoic east-west normal fault trend which is truncated by younger serpentinitefilled, north-south shear zones. The younger fault trend was active into the Tertiary as the faults cut the Eocene. Detrital modal analyses of sandstones suggest that the Otter Point is related to the coeval Dothan Formation of the interior Klamath Mountains, in the same way that the Franciscan is related to the Great Valley sequence in California. The detrital modal analysis indicates that the Otter Point is trench-slope deposited sediments as is the Franciscan and the Dothan is forearc basin deposits similar to the Great Valley.
5

Comportas abertas para o risco: análise geográfica da inundação brusca ocorrida em Areal, RJ, em 12 de janeiro de 2011

Muniz, Emerson de Oliveira 31 October 2013 (has links)
Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-05-06T12:12:14Z No. of bitstreams: 1 emersondeoliveiramuniz.pdf: 8307586 bytes, checksum: 606af644defaa4b8c7ac04fed4b1bcbd (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2016-06-07T15:51:16Z (GMT) No. of bitstreams: 1 emersondeoliveiramuniz.pdf: 8307586 bytes, checksum: 606af644defaa4b8c7ac04fed4b1bcbd (MD5) / Made available in DSpace on 2016-06-07T15:51:16Z (GMT). No. of bitstreams: 1 emersondeoliveiramuniz.pdf: 8307586 bytes, checksum: 606af644defaa4b8c7ac04fed4b1bcbd (MD5) Previous issue date: 2013-10-31 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Numa contemporaneidade na qual as estatísticas apontam o incremento dos chamados desastres naturais em todo o mundo, sobretudo em nações como o Brasil, onde o crescente adensamento populacional nas cidades faz delas as áreas preferenciais para a realização das catástrofes, especialmente quando marcadas pela desigualdade social e pela baixa capacidade institucional de prevenção e gerenciamento desses fenômenos. A presente pesquisa faz uma interpretação geográfica do evento de inundação brusca ocorrido na cidade de Areal – RJ no dia 12 de janeiro de 2011, diretamente vinculado à catástrofe socioambiental que se processou na Região Serrana do estado naquela data. A partir da experiência vivenciada pelo próprio autor como testemunha e vítima do desastre em Areal, o trabalho registra como o evento se processou no tempo e no espaço e discute numa proposta integradora as condicionantes físicas e socioinstitucionais relacionadas ao fato da cidade ter tido a quase totalidade de sua área urbana fortemente impactada pela inundação. Dentre as condicionantes analisadas ressalta-se a presença e a operação da barragem Morro Grande, um reservatório para aproveitamento hidrelétrico a montante e próximo da área urbana do município. Duas paisagens são consideradas na interpretação, a da bacia hidrográfica do rio Piabanha e a da área urbana do município de Areal, cidade localizada no curso médio do rio que dá nome à bacia. As interações natureza-sociedade na geração do desastre, o mapeamento da área urbana afetada no evento de 2011, a análise da capacidade político-institucional de resposta à crise e o ordenamento urbano de Areal no engendramento de riscos são aspectos averiguados na pesquisa. Com base na proposta de Libaut (1971), a metodologia obedeceu quatro etapas seqüenciadas e empregou técnicas de trabalho de campo, entrevistas e mapeamento da área inundada. A pesquisa conclui que o evento na cidade foi de grande porte, deflagrado por um contexto de exceção na dinâmica flúvio-meteorológica regional, mas amplificado por fatores ligados à própria espacialidade local. / At the present times, the statistics are aiming to the increase of those called “global nature disasters”, particularly in nations like Brazil where the population of small and big cities are in constant development which contribute in addition to, the weakness of the administration and management of the prevention of disasters like the one that occurred at the city of Areal- RJ on January 12, 2011. The present work made a geographical interpretation of that event that might be the cause for that sudden flood that covered the city, located near at the highlands region of Rio de Janeiro. From that self-experience as a witness and victim the author, present a friendly proposition to discuss the construction and operation of the Morro Grande, located near that urban area and used as a Hydroelectric Reservoir to the enhancement of the region. At this point there are multiple factors to be analyzed like the area between the rivers, the urban area, the interaction nature-society, description of the area affected, the capacity political-institutional to respond to these type of events. This work is in according with Libaut (1971), this work follow the four steps and technical of work on the field. Interviews and description of the area object of this work. The paper concludes that the event in the city was large, triggered by an exception in the context of river dynamics and regional weather, but amplified by factors related to spatiality own site.
6

Characterization and improvement of copper/glass adhesion

He, Baofeng January 2012 (has links)
The development of glass substrates for use as an alternative to printed circuit boards (PCBs) attracts significant industrial attention, because of the potential for low cost but high performance interconnects and optical connection. Electroless plating is currently used to deposit conductive tracks on glass substrates and the quality of copper / glass adhesion is a key functional issue. Without adequate adhesive strength the copper plating will prematurely fail. Existing studies have covered the relationship between surface roughness and adhesion performance, but few of them have considered the detail of surface topography in any depth. This research is specifically considering the mechanical contribution of the glass surface texture to the copper / glass adhesive bond, and attempting to isolate new ISO 25178 areal surface texture parameters that can describe these surfaces. Excimer laser machining has been developed and used to create a range of micro pattern structured surfaces on CMG glass substrates. Excimer mask dimensions and laser operation parameters have been varied and optimized according to surface topography and adhesion performance of the samples. Non-contact surface measurement equipment (Zygo NewView 5000 coherence scanning interferometry) has been utilized to measure and parameterize (ISO 25178) the surface texture of the glass substrates before electroless copper metallization. Copper adhesion quality has been tested using quantitative scratch testing techniques, providing an identification of the critical load of failure for different plated substrates. This research is establishing the statistical quality of correlation between the critical load values and the associated areal parameters. In this thesis, the optimal laser processing parameter settings for CMG glass substrate machining and the topographic images of structured surfaces for achieving strong copper / glass plating adhesion are identified. The experimental relationships between critical load and areal surface parameters, as well as the discussions of a theoretical approach are presented. It is more significant to consider Sq, Sdq, Sdr, Sxp, Vv, Vmc and Vvc to describe glass substrate surface topography and the recommended data value ranges for each parameter have been identified to predict copper / plating adhesion performance.
7

Mechanical durability of hydrophobic surfaces fabricated by injection moulding of laser-induced textures

Romano, J.-M., Gulcur, Mert, Garcia-Giron, A., Martinez-Solanas, E., Whiteside, Benjamin R., Dimov, S.S. 23 January 2020 (has links)
Yes / The paper reports an investigation on the mechanical durability of textured thermoplastic surfaces together with their respective wetting properties. A range of laser-induced topographies with different aspect ratios from micro to nanoscale were fabricated on tool steel inserts using an ultrashort pulsed near infrared laser. Then, through micro-injection moulding the topographies were replicated onto polypropylene surfaces and their durability was studied systematically. In particular, the evolution of topographies on textured thermoplastic surfaces together with their wetting properties were investigated after undergoing a controlled mechanical abrasion, i.e. reciprocating dry and wet cleaning cycles. The obtained empirical data was used both to study the effects of cleaning cycles and also to identify cleaning procedures with a minimal impact on textured thermoplastic surfaces and their respective wetting properties. In addition, the use of 3D areal parameters that are standardised and could be obtained readily with any state-of-the-art surface characterisation system are discussed for monitoring the surfaces’ functional response. / The full-text of this article will be released for public view at the end of the publisher embargo on 23 Jan 2020.
8

Simulation study of areal sweep efficiency versus a function of mobility ratio and aspect ratio for staggered line-drive waterflood pattern

Guliyev, Ruslan 10 October 2008 (has links)
Pattern geometry plays a major role in determining oil recovery during waterflooding and enhanced oil recovery operations. Although simulation is an important tool for design and evaluation, the first step often involves rough calculations based upon areal sweep efficiencies of displacements in homogeneous, two-dimensional, scaled, physical models. These results are available as a function of the displacement pattern and the mobility ratio M. In this research I studied the effect of mobility ratios on five-spot and staggered waterflood patterns behavior for areal (2D) displacement in a reservoir that is homogeneous and isotropic containing no initial gas saturation. Simulation was performed using Eclipse 100 simulator. Simulation results are presented as graphs of areal sweep efficiency at breakthrough versus Craig mobility ratio for various staggered line drive aspect ratios. The main results of the study are presented in the form of a graph of areal sweep efficiency at breakthrough as a function of staggered line drive aspect ratio. This should enable engineers to utilize the results in a convenient manner.
9

The valuation of urban realty for purposes of taxation /

King, Willford Isbell. January 1014 (has links)
University of Wisconsin, 1913, Thesis (doctoral). / "April, 1914. - Also paged [135]-245. - Includes bibliographical references. - RLIN, CTRG96-B2505. - Reproduction of original from Harvard Law School Library.
10

Wuchsform, Wuchsrhythmus und Verbreitung der Arten der Zwergbinsengesellschaften : mit 9 Tab. /

Lampe, Maud von. January 1996 (has links) (PDF)
Zugl.: Halle, Univ., Diss., 1996.

Page generated in 0.0281 seconds