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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.
1

Aurora, Illinois a study in sequent land use,

Carlson, Carl Frederick, January 1940 (has links)
Thesis (Ph. D.)--University of Chicago, 1940. / The plates, maps, and plans are folded in pockets at each end. Lithoprinted. "Private edition, distributed by the University of Chicago libraries, Chicago, Illinois." Bibliography: p. 118-121.
2

Enhanced pitch angle diffusion due to stochastic electron-whistler wave-particle interactions

Wykes, William John January 2001 (has links)
No description available.
3

Fine-scale morphology and spectral characteristics of active aurora

Dahlgren, Hanna January 2008 (has links)
<p>Ground-based and in-situ observations of the aurora demonstrate an extreme richness in fine structure, with spatial scales down to tens of metres and time variations occurring on a fraction of a second. To further our understanding of the aurora, it is esssential to understand the mechanisms responsible for the small-scale structuring, since this is an intrinsic property of the auroral plasma. Still many questions about dynamics and structuring of aurora on small scales remain unanswered. In this thesis the low-light optical instrument ASK (Auroral Structure and Kinetics) is used to image small-scale structures in the aurora at very high spatial and temporal resolution. ASK is a multi-spectral instrument, imaging the aurora in three selected emission lines simultaneously. This provides information on the energy of the precipitating electrons. The SIF (Spectrographic Imaging Facility) instrument has been used in conjunction with ASK, to give a more complete picture of the spectral characteristics of the aurora, and to determine the contamination of the emission lines by other emissions. Data from ASK and SIF is used to study the relation between the morphology and dynamics of small-scale structures in the aurora and the energy of the precipitating electrons. By comparing electron density profiles provided by EISCAT (European Incoherent SCATter) measurements with modeling results, information on characteristic energy and energy flux of the precipitating electrons can be obtained. One of the ASK channels is imaging a metastable O+ emission, which has a lifetime of 5 s. By tracing the afterglow in this channel optically a direct measure of the E × B drift and thus of the local ionospheric electric fields is provided.</p>
4

Auroral and meteor applications of the EISCAT incoherent scatter radar

Pellinen-Wannberg, Asta January 1995 (has links)
<p>Diss. (sammanfattning) Umeå : Umeå universitet, 1995, härtill 5 uppsatser.</p> / digitalisering@umu
5

Cluster in situ studies of the auroral acceleration region

Li, Bin January 2014 (has links)
This thesis addresses a central topic in auroral physics, namely particle accelerationproducing intense aurora as well as energetic plasma outflow. Cluster satellitemeasurements of electric and magnetic fields, electrons and ions, collected across auroralfield lines, are used to study various aspects of the quasi-static auroral accelerationregion (AAR), its relation to the auroral density cavity, and the relative role of quasistaticand Alfvénic acceleration for producing aurora.The acceleration potential structures and electro-dynamical features of a large-scaleauroral surge is studied based on data from the Cluster satellites, crossing differentmagnetic local time (MLT) sectors of a surge-horn system. This allows snapshots of theacceleration potential structure and of the current systems to be provided, including thefield-aligned current closure for the different segments of the surge-horn aurora.The relative role of quasi-static and Alfvénic acceleration for producing auroral arcs isaddressed for the case of a large-scale substorm surge, crossed by the Cluster C2 satellite. Thetwo contributions to the downward electron energy flux is estimated for each of the smallerscalearc structures crossed by C2 within and adjacent to the large-scale surge. For these, thequasi-static acceleration typically dominates, except for the polar cap boundary arc, and in thesurge head, where the Alfvénic contribution is significant.The occurrence of intense electric fields and associated plasma densities versus altitude andMLT is the subject of a statistical study based on 9.5 years of Cluster data, collected ataltitudes between 2 and 4 RE. Intense arc-associated electric fields occur in two altituderegions, separated by a gap around 2.8 RE. The low-altitude fields are interpreted as mainlyquasi-static and the high-altitude fields as mainly Alfvénic. The results which are supportedby estimates of the (ΔE/ΔB)/VA ratio, indicate that, on the average, the quasi-static fieldsextend up to 2.6 RE, above which a transition to Alfvénic fields occur.The auroral density cavity, intimately associated with the auroral acceleration process, wasthe subject of a statistical study based on Cluster data, collected between 2002 and 2007, ataltitudes between 2.0 RE and 5.5 RE. Decreasing electron densities are observed between 2 and 3.3 RE, and between 4.6 and 5.5 RE, corresponding to climbing the parallel potential hillof the AAR. Furthermore, the density is found to decrease while ascending above the AAR,indicating that the cavities are not necessarily confined by it. / <p>QC 20141110</p>
6

Aurora: uma obra de transição na filosofia de Nietzsche? / Daybreak: a work of transition in the philosophy of the Nietzsche?

Dias, Geraldo Pereira [UNIFESP] 12 1900 (has links) (PDF)
Submitted by Andrea Hayashi (deachan@gmail.com) on 2016-06-24T13:01:06Z No. of bitstreams: 1 dissertacao-geraldo-pereira-dias.pdf: 757605 bytes, checksum: 723da0713683522d08f10bc80c2a9d3a (MD5) / Approved for entry into archive by Andrea Hayashi (deachan@gmail.com) on 2016-06-24T13:02:56Z (GMT) No. of bitstreams: 1 dissertacao-geraldo-pereira-dias.pdf: 757605 bytes, checksum: 723da0713683522d08f10bc80c2a9d3a (MD5) / Made available in DSpace on 2016-06-24T13:02:56Z (GMT). No. of bitstreams: 1 dissertacao-geraldo-pereira-dias.pdf: 757605 bytes, checksum: 723da0713683522d08f10bc80c2a9d3a (MD5) Previous issue date: 2013-12 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / No presente trabalho, temos por objetivo analisar a hipótese de que o livro Aurora, no conjunto dos escritos de Friedrich Nietzsche, mostra-se como uma obra de transição. Nesse livro, mostraremos que Nietzsche começa a criar um quadro teórico que lhe possibilitará desenvolver temas centrais de sua filosofia. Com essa interpretação, faremos ver que, justamente por causa desse caráter transitório, essa obra tem sido tão subestimada. Atualmente Aurora suscita um interesse renovado na pesquisa internacional sobre Nietzsche; ainda sim, muitas vezes nos depararmos com leituras que tendem a desconsiderar seu caráter transitório, e, por isso mesmo, acabam por obscurecê-la. Isso tem ocorrido sempre que os comentadores interpretam Aurora à luz de conceitos, projetos e doutrinas filosóficas posteriores ao livro. Para nos contrapor a essa literatura que tende a submeter Aurora à filosofia tardia de Nietzsche, pretendemos analisá-la em seu tempo próprio, única maneira de verificar em que sentido as ideias presentes no livro contribuíram para viabilizar a construção de conceitos tais como genealogia, vontade de potência e transvaloração dos valores. / In this work, we aim to examine the hypothesis that the book Daybreak, in all the writings of Friedrich Nietzsche, shows up as a transitional work. In this book, we will show that Nietzsche begins to create a theoretical framework that will enable you to develop the central themes of his philosophy. With this interpretation, we see that, precisely because of this character transitive, this work has been so underestimated. Currently Daybreak raises renewed interest in international research on Nietzsche; yet, often we encounter readings that tend to disregard their transitory character, and, therefore, end up obscuring it. This has occurred whenever the commentators interpret Daybreak through of the concepts, designs and philosophical doctrines after the book. To counter this in the literature tends to refer to the Daybreak later philosophy of Nietzsche, we intend to analyze it on your own time, the only way to check which way the ideas presented in the book contributed to enable the construction of the concepts such as genealogy, will to Power and Re-evaluation of Values.
7

Aurora: uma obra de transição na filosofia de Nietzsche? / Daybreak: a work of transition in the philosophy of the Nietzsche?

Dias, Geraldo Pereira [UNIFESP] 03 December 2013 (has links)
Submitted by Cristiane de Melo Shirayama (cristiane.shirayama@unifesp.br) on 2018-04-05T21:16:22Z No. of bitstreams: 1 Aurora.pdf: 757605 bytes, checksum: 723da0713683522d08f10bc80c2a9d3a (MD5) / Approved for entry into archive by Diogo Misoguti (diogo.misoguti@gmail.com) on 2018-04-06T11:54:37Z (GMT) No. of bitstreams: 1 Aurora.pdf: 757605 bytes, checksum: 723da0713683522d08f10bc80c2a9d3a (MD5) / Made available in DSpace on 2018-04-06T11:54:37Z (GMT). No. of bitstreams: 1 Aurora.pdf: 757605 bytes, checksum: 723da0713683522d08f10bc80c2a9d3a (MD5) Previous issue date: 2013-12-03 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / No presente trabalho, temos por objetivo analisar a hipótese de que o livro Aurora, no conjunto dos escritos de Friedrich Nietzsche, mostra-se como uma obra de transição. Nesse livro, mostraremos que Nietzsche começa a criar um quadro teórico que lhe possibilitará desenvolver temas centrais de sua filosofia. Com essa interpretação, faremos ver que, justamente por causa desse caráter transitório, essa obra tem sido tão subestimada. Atualmente Aurora suscita um interesse renovado na pesquisa internacional sobre Nietzsche; ainda sim, muitas vezes nos depararmos com leituras que tendem a desconsiderar seu caráter transitório, e, por isso mesmo, acabam por obscurecê-la. Isso tem ocorrido sempre que os comentadores interpretam Aurora à luz de conceitos, projetos e doutrinas filosóficas posteriores ao livro. Para nos contrapor a essa literatura que tende a submeter Aurora à filosofia tardia de Nietzsche, pretendemos analisá-la em seu tempo próprio, única maneira de verificar em que sentido as ideias presentes no livro contribuíram para viabilizar a construção de conceitos tais como genealogia, vontade de potência e transvaloração dos valores. / In this work, we aim to examine the hypothesis that the book Daybreak, in all the writings of Friedrich Nietzsche, shows up as a transitional work. In this book, we will show that Nietzsche begins to create a theoretical framework that will enable you to develop the central themes of his philosophy. With this interpretation, we see that, precisely because of this character transitive, this work has been so underestimated. Currently Daybreak raises renewed interest in international research on Nietzsche; yet, often we encounter readings that tend to disregard their transitory character, and, therefore, end up obscuring it. This has occurred whenever the commentators interpret Daybreak through of the concepts, designs and philosophical doctrines after the book. To counter this in the literature tends to refer to the Daybreak later philosophy of Nietzsche, we intend to analyze it on your own time, the only way to check which way the ideas presented in the book contributed to enable the construction of the concepts such as genealogy, will to Power and Re-evaluation of Values.
8

Study of fabric movement in garment architecture, facade materials, and building in the arctic

Hudacek, Kaija 07 February 2024 (has links)
This thesis documents the academic year progress of researching building in the Arctic circle, household material study in garments, building facade materials, and Arctic experiences with northern lights. This thesis is has many iterations and direction of study from chip board massing models to sewing fabrics to see their integrity. This document shows both design iterations and reflection of each work. The final project of this document is a design proposal for 'The Arctic Experience' - a full service experience for tourists to have a place to visit the arctic circle and view the northern lights. From the provided transportation to their stay in the building, and back they will get to experience the arctic. / Master of Architecture / This document contains thesis iterations and research from the fall and spring academic semesters. The fall semester was research and material study heavy, while the spring semester's project development lead to project design iterations. The fall was spent researching the arctic circle, building construction in that zone, and the aurora Borealis. Then there was a brief shift in ideas - moving toward material study and garment architecture - taking household items and seeing how they can be re-formed. By the end of the thesis, material on building facades was studied and then later a development for the arctic was proposed.
9

VHF radar aurora : statistics, fading and correlation with optical aurora

Mu, Jun 01 January 1996 (has links)
This thesis presents the studies of aurora using three observation instruments; the SAPPHIRE SOUTH VHF radar system, the ASC (All-Sky Camera) system at Rabbit Lake, Saskatchewan, and the 50-MHz CW (Continuous Wave) bistatic Doppler radars in the 1981 campaign. The SAPPHIRE SOUTH radar system, which has a high temporal and frequency resolution, is a multi-beam CW bistatic VHF Doppler radar system. Two transmitters, located at La Crete (Alberta), and Gillam (Manitoba), transmitted on four transmitter beams for each transmitter and intersected with four receiver beams from Saskatoon, Saskatchewan to form 32 radar target regions in the lower E-region of the ionosphere. The ASC system at Rabbit Lake provides digitized high resolution optical auroral images at several wavelengths (557.7 nm, 630.0 nm) and for the whole visible spectrum. The observing region of the ASC system covered all the radar target regions of the SAPPHIRE SOUTH radar system. The 50 MHz CW bistatic Doppler radars in the 1981 campaign had a special radar setup with three transmitters and two receivers to provide multiple radar beams with different aspect and flow angles. The AE index and Kp index data have been compared with the radar Doppler spectral characteristics extracted by using software designed for peak-finding and curve-fitting. The radar data received by the SAPPHIRE SOUTH radar system have been compared with the optical data obtained by the ASC: system in Rabbit Lake. The results showed that strong Type 1 and Type 3 radar auroral echoes were received along the auroral arc alignment while weak Type 2 echoes were observed in the direction perpendicular to the auroral arc alignment. The power of radar auroral echoes received along the auroral arc alignment was well correlated with the standard deviation of the optical auroral emission inside the radar target region. The non-linear theory of the Type 3 radar auroral echoes has also been examined. A fading analysis has been applied to the SAPPHIRE SOUTH radar data to examine whether the electromagnetic ion cyclotron (EMIC) wave caused the fading of VHF radar auroral signals. The results showed that fading frequency ranges of Type 3 and Type 4 echoes were consistent with electric field oscillation and primary particle modulation arising from EMIC waves. The results of statistical studies on the data obtained from the radars in the 1981 campaign showed that the power of radar auroral backscatter echoes received by the radar link with a large aspect angle (4.08°) and a small assumed flow angle (6.17°) correlated well with the AE index. Regardless of the AE index, strong radar auroral backscatter echoes were observed by the radar link with smallest aspect angle (1.57°). Type 1 and Type 5 radar auroral backscatter mostly occurred for large values of the AE index, while Type 2 and Type 3 radar auroral backscatter echoes were mostly observed for small values of the AE index.
10

AURORA-A, A POTENTIAL TARGET IN PANCREATIC CANCER AND ITS STRUCTURAL ROLE IN LOCALIZATION TO THE CENTROSOMES

Rojanala, Sangeeta January 2005 (has links)
Aurora-A kinase is overexpressed in many human cancers and leads to centrosome amplification resulting in multipolar spindles, chromosome segregation defects and aneuploidy. Aurora-A belongs to a family of serine/threonine mitotic kinases involved in centrosome separation, duplication and maturation as well as in bipolar spindle assembly. In this work, we demonstrate that Aurora-A is both amplified and overexpressed in human pancreatic cancer cell lines, with a 2-5 fold increase in gene copy number and a 3-4 fold increase in protein levels compared to controls. Aurora-A is also amplified and overexpressed in pancreatic cancers taken directly from patients. An immunohistochemistry of tissues taken directly from patients demonstrated an overexpression of Aurora-A in 26 of 28 pancreatic cancers compared to 0 of 18 normal pancreas samples. Antisense nucleotides specifically targeted at Aurora-A arrest the cell cycle in pancreatic cancer cells, indicating the potential of Aurora-A as a therapeutic target in pancreatic cancer. To understand the role of Aurora-A at the centrosome, we investigated the mechanism of how Aurora-A is targeted to the centrosome. We used deletion fragment analysis of Aurora-A to identify a specific region that is required to localize to the centrosome. We also show that subcellular localization of Aurora-A is independent of its intrinisic kinase activity and its phosphorylation states. These results show that Aurora-A is targeted to the centrosome by a mechanism that does not require its kinase activity and phosphorylation of T288 and T287. Furthermore, the region containing the catalytic domain, 131-333, is sufficient to localize Aurora-A to the centrosome.

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