• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 6
  • 1
  • 1
  • Tagged with
  • 12
  • 12
  • 4
  • 4
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 1
  • 1
  • 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

On the origin of sporadic neutral sodium layers

Cox, Rachel Mary January 2001 (has links)
No description available.
2

Tropical dynamics and transport associated with stratospheric warmings

Iwi, Alan Michael January 1998 (has links)
No description available.
3

Inter-university Upper atmosphere Global Observation NETwork (IUGONET) project

Hashiguchi, N.O., Yatagai, Akiyo, Kaneda, Naoki, Umemura, Norio, UeNo, Satoru, Yagi, Manabu, Koyama, Yukinobu, Sato, Yuka, Shinbori, Atsuki, Tanaka, Yoshimasa, Abe, Shuji, Hori, Tomoaki 25 June 2013 (has links)
International Living With a Star Workshop 2013, 2013/06/24-6/28, Irkutsk, Russia
4

Upper atmosphere tides and gravity waves at mid- and low-altitudes /

Ball, Susan Margaret. January 1981 (has links) (PDF)
Thesis (Ph.D.) -- University of Adelaide, Dept. of Physics, 1982. / Typescript (photocopy).
5

Diatomic collision models used in the Monte-Carlo direct simulation method applied to rarefied hypersonic flows

Macrossan, M. N. January 1984 (has links)
No description available.
6

Comparison of the Martian thermospheric density and temperature from IUVS/MAVEN data and general circulation modeling

Medvedev, Alexander S., Nakagawa, Hiromu, Mockel, Chris, Yiğit, Erdal, Kuroda, Takeshi, Hartogh, Paul, Terada, Kaori, Terada, Naoki, Seki, Kanako, Schneider, Nicholas M., Jain, Sonal K., Evans, J. Scott, Deighan, Justin I., McClintock, William E., Lo, Daniel, Jakosky, Bruce M. 16 April 2016 (has links)
Newly released Imaging Ultraviolet Spectrograph/Mars Atmosphere and Volatile EvolutioN (IUVS/MAVEN) measurements of CO2 density in the Martian thermosphere have been used for comparison with the predictions of the Max Planck Institute Martian General Circulation Model (MPI-MGCM). The simulations reproduced (within one standard deviation) the available zonal mean density and derived temperature above 130 km. The MGCM replicated the observed dominant zonal wave number 3 nonmigrating tide and demonstrated that it represents a nonmoving imprint of the topography in the thermosphere. The comparison shows a great dependence of the simulated density and temperature to the prescribed solar flux, atomic oxygen abundances and gravity wave effects, with the former two being especially important in the thermosphere above 130 km and the latter playing a significant role both in the mesosphere and thermosphere.
7

Non-migrating tides in the Martian thermosphere

Kumar, Aishwarya S. 02 August 2018 (has links)
Previous studies have identified longitudinal structures associated with non-migrating tides in observations of the upper neutral atmosphere of Mars. MAVEN’s Imaging Ultraviolet Spectrometer (IUVS) observations of the upper atmosphere reveal variations in density with longitude at altitudes of 130 – 200 km, and can be used to identify non-migrating tides. These observations cover higher latitudes and allow for studying the local time variations of tides. The analysis presented here shows that the longitudinal structure attributed to non-migrating tides is dominated by wavenumber 2 and wavenumber 3 harmonics during the periods studied. Comparison with the Neutral Ion and Gas Mass spectrometer (NGIMS) shows a good agreement in wave amplitudes observed for the first two cases studied. The temperatures and 𝑂/𝐶𝑂# ratios from the IUVS L2 data files revealed an anti-correlation with the densities which confirms the theoretical interpretation from the linear wave theory. / Master of Science / There are waves internal to all fluids in our surroundings and daily lives, such as sound waves. Waves in the atmosphere are also fluid in nature. In planetary atmospheres, the scale sizes of some of these waves become comparable to the size of the planet itself. The waves interact with the structure of the surface of Mars to form a certain type of wave called “Non-migrating tides”. These waves have been observed in multiple previous studies in the upper atmosphere of Mars (~130 km and above). These waves cause the atomic and molecular content of the upper atmosphere to be displaced in a particular manner to form a unique structure. The structures formed are observed on a scale that covers the entire planet. It is by studying these structures in the upper atmosphere that it is possible to characterize the waves that control them and thereby understand their nature and impact. Understanding how these waves vary helps spacecraft to gain better control over mechanisms required to swing them into the desired orbit (location). This study uses the observations from an instrument aboard the MAVEN mission and compares it to the observations from another instrument aboard the same mission. The results of this study demonstrate that these “Non-migrating” tides play a vital role in controlling the behavior of the upper atmosphere.
8

Study on dynamics in the mesosphere, thermosphere and ionosphere with optical observations from the International Space Station / 国際宇宙ステーションからの光学観測を用いた中間圏、熱圏、電離圏のダイナミクスの研究

Hozumi, Yuta 23 March 2017 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第20186号 / 理博第4271号 / 新制||理||1614(附属図書館) / 京都大学大学院理学研究科地球惑星科学専攻 / (主査)准教授 齊藤 昭則, 教授 田口 聡, 教授 塩谷 雅人 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DGAM
9

Variações nas marés atmosféricas e nos ventos meteóricos observados em São João Do Cariri-PB e em Cachoeira Paulista-SP. / Variations in atmospheric tides and winds meteoric observed in São João do Cariri-PB and Cachoeira Paulista-SP

Borges, Fabricio Batista 04 April 2010 (has links)
Made available in DSpace on 2015-09-25T12:23:41Z (GMT). No. of bitstreams: 1 Fabricio Batista Borges.pdf: 1546340 bytes, checksum: 1d8be2583a092a34d256d749548325ef (MD5) Previous issue date: 2010-04-04 / Meteor wind measurements obtained from São João do Cariri B and Cachoeira Paulista SP, Brazil, obtained during the period from August 2004 to July 2006 were used to examine Variations in atmospheric tides and winds in the mesopause region of the equatorial and low Latitudes in the southern hemisphere. The results for the mean wind were compared with the HWM 93 and HWM 07 models (Horizontal neutral wind model) and the results of Atmospheric tides with GSWM 02 model (Global Scale Wave Model). From the analysis of These data it was observed that the mean wind, as well as diurnal fluctuations, showed Temporal and in altitude variations for both the zonal and to the south for both the localities investigated. Mean zonal winds for the region of the S. J. do Cariri show a structure that is characterized by a semi annual oscillation, with a flow westward most of the time, in accordance with HWM 07 model. The mean zonal wind at C. Paulista is eastward in the most time and presents a semi annual variation in the 80 90 km altitude range and an annual variation in the altitudes above, in which some aspects are in accordance with HWM 93 and 07 models. The amplitudes of the mean meridional winds were weaker than zonal and present An annual variation for both sites, which are in accordance with HWM 93 model, however the HWM 07 do not reproduce the observed behavior. The meridional diurnal tide amplitudes Showed semi annual variation with maximum of the up to 65 m/s during February April and August September. The vertical wavelength estimated reached values between 21.2 and 27.5 Km at S. J. do Cariri, smaller than the GSWM 02, whereas to C. Paulista the vertical Wavelength were determined between 24 and 31.9 km, near of the GSWM 02 model, but More than the diurnal tide meridional wavelength for Cariri. / Medidas de vento meteóricos obtidos em São João do Cairi-PB e Cachoeira Paulista-SP Brasil, realizadas durante o período compreendido entre agosto de 2004 a julho de 2006, foram usadas para investigar as variações nas marés atmosféricas e nos ventos meteóricos na região da mesopausa equatorial e de baixas latitudes do hemisfério sul. Os resultados obtidos para os ventos médios foram comparados com os modelos HWM 93 e HWM 07 (Horizontal Neutral Wind Model) e os resultados das marés atmosféricas com GSWM 02 (Global Scale Wave Model). A partir da análise destes dados, foi possível observar que os ventos médios, Assim como as oscilações diurnas, apresentaram variação temporal e em função da altura, tanto para a componente zonal como para a meridional para ambas as localidades investigadas. Os ventos médios na direção zonal para região de S. J. do Cariri mostram uma estrutura que é Caracterizada por uma oscilação semi anual, apresentando um escoamento para oeste na maior Parte do tempo, semelhante com o modelo HWM 07. Já o vento médio zonal verificado na Região de C. Paulista é predominante para leste com variação semi anual entre 80 e 90 km e Anual nas altitudes acima, semelhante em alguns aspectos com os modelos HWM 93 e 07. O Escoamento médio na direção meridional apresenta amplitudes menores do que as do zonal e Oscilação anual para ambas as localidades, a qual é semelhante com o modelo HWM 93, Porém o modelo HWM 07 não reproduz o comportamento observado. As amplitudes da maré Diurna para a componente meridional mostraram variação semi anual com máximos de até 65 m/s em fevereiro abril e agosto setembro. Comprimentos de onda vertical para a componente meridional foram estimados entre 21,2 e 27,5 km para S. J. do Cariri, menores do que as observadas pelo modelo GSWM 02, enquanto que para C. Paulista os comprimentos de onda assumiram valores entre 24 e 31,9 km, próximos aos previstos, porém maiores do que os de Cariri.
10

Robust adaptive beamforming for clutter rejection on atmospheric radars / 大気レーダーのための適応的クラッター抑圧手法

Hashimoto, Taishi 23 September 2016 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(情報学) / 甲第20034号 / 情博第629号 / 新制||情||109(附属図書館) / 33130 / 京都大学大学院情報学研究科通信情報システム専攻 / (主査)教授 佐藤 亨, 教授 守倉 正博, 教授 山本 衛 / 学位規則第4条第1項該当 / Doctor of Informatics / Kyoto University / DFAM

Page generated in 0.0631 seconds