SH Waves in a Transversely Isotropic Medium–II Transradial!? Isotropic Cylinder     

R. Sato  E. R. Lapwood 《Geophysical Journal International》1968,16(5):461-473

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Responses of the polar ionosphere to the Bastille Day solar event   总被引：1，自引：0，他引：1  

Liu  Rui-yuan  Hu  Hong-qiao  Liu  Yong-hua  Xu  Zhong-hua  Sato  N.  Fraser  B.J. 《Solar physics》2001,204(1-2):305-313

Simultaneous observations at Zhongshan Station, Antarctica, are presented for the interval of 13–17 July 2000 to show responses of the polar ionosphere to the Bastille Day (14 July 2000) solar event. The polar ionosphere was highly disturbed, as shown by frequently large deviations of the geomagnetic H-component, large riometer absorption events and strong ULF waves. Associated with the huge solar proton event produced by the X5/3B flare, a polar cap absorption (PCA) was observed. It began at ∼ 10:40 UT on 14 July and ended at ∼ 19:40 UT on 17 July. Superposed on it, there was a large absorption event with a peak of 26 dB, starting at ∼ 03:00 UT and ending at ∼ 11:10 UT on 15 July. This kind of absorption was probably produced by an intense `cloud of energetic electrons' during an auroral substorm. The ULF waves were very intense during the main phase and the recovery phase of the severe magnetic storm on 15 and 16 July. The ionospheric absorption was so strong that the digisonde signal was blacked out most of the time. The ionosphere returned to normal in the afternoon on 17 July.  相似文献   

A planetary companion orbiting the intermediate-mass G Giant HD 173416     

Yu-Juan Liu Bun＇ei Sato Gang Zhao Hiroyasu Ando 《中国天文和天体物理学报》2009,9(1)

The discovery of a planetary companion to the intermediate-mass late-type giant star HD173416 from precise Doppler surveys of G and K giants at Xingiong station and Okayama Astrophysical Observatory (OAO) is presented in this letter. The planet has a minimum mass of 2.7 MJ an eccentricity of 0.21, a semimajor axis of 1.16 AU and an orbital period of 324 days.  相似文献   

Automated cloud tracking system for the Akatsuki Venus Climate Orbiter data     

Kazunori Ogohara  Toru Kouyama  Hiroki Yamamoto  Naoki Sato  Masahiro Takagi  Takeshi Imamura 《Icarus》2012,217(2):661-668

Japanese Venus Climate Orbiter, Akatsuki, is cruising to approach to Venus again although its first Venus orbital insertion (VOI) has been failed. At present, we focus on the next opportunity of VOI and the following scientific observations.We have constructed an automated cloud tracking system for processing data obtained by Akatsuki in the present study. In this system, correction of the pointing of the satellite is essentially important for improving accuracy of the cloud motion vectors derived using the cloud tracking. Attitude errors of the satellite are reduced by fitting an ellipse to limb of an imaged Venus disk. Next, longitude–latitude distributions of brightness (cloud patterns) are calculated to make it easy to derive the cloud motion vectors. The grid points are distributed at regular intervals in the longitude–latitude coordinate. After applying the solar zenith correction and a highpass filter to the derived longitude–latitude distributions of brightness, the cloud features are tracked using pairs of images. As a result, we obtain cloud motion vectors on longitude–latitude grid points equally spaced. These entire processes are pipelined and automated, and are applied to all data obtained by combinations of cameras and filters onboard Akatsuki. It is shown by several tests that the cloud motion vectors are determined with a sufficient accuracy. We expect that longitude–latitude data sets created by the automated cloud tracking system will contribute to the Venus meteorology.  相似文献   

What motivates single women to migrate from northern Ghana to Accra?     

Theresa Tufuor  Chizu Sato 《Norsk geografisk tidsskrift. Norwegian journal of geography》2017,71(1):46-59

In recent decades there has been a large migration stream of single women from the north to Accra in Ghana. Existing studies have focused on young migrant women’s livelihood strategies in their place of destination. However, once-married women – divorced and widowed women and neglected wives – also migrate, and their motivations for migration are less known. Drawing on qualitative and quantitative methods, the authors investigate the effects of gender norms, age, marital status, socio-economic status, and position in households on women’s decisions to migrate. The results revealed that migrant women from resource-poor households, regardless of age, marital status and position in households, commonly cited a gain in autonomy as an important motivation for their migration. From a differentiated perspective, young unmarried women aspired to prepare themselves for often expensive religious marriage ceremonies, whereas once-married women invest in their children’s education and build their own housing. By paying attention to the effects of gender norms, age, marital status, socio-economic status, and position in households on women’s decisions to migrate, the study illuminates the contradictory ways in which their migration practices are both shaped by and shape gender ideologies in parts of contemporary northern Ghana.  相似文献   

土地利用变化研究中的细胞自动机与灰色局势决策     

贾华  祝国瑞  佐藤洋平 《武汉大学学报(信息科学版)》1999,(2)

把细胞自动机和灰色局势决策结合起来对土地利用变换机制进行模拟。实验证明,基于灰色局势决策规则的细胞自动机是对土地利用变换机制从宏观和微观角度进行模拟的有效方法。  相似文献   

满洲里-新巴尔虎右旗斑岩系列矿床石英流体包裹体液相组分的PIXE分析和地质应用   总被引：1，自引：0，他引：1  

王莉娟  石山大三  佐藤比奈子  世良耕一郎  王玉往 《地球化学》1999,(2)

ＰＩＸＥ（质子感应Ｘ射线分析）方法是目前国际上新的流体包裹体成分分析方法。在前人工作的基础上,尝试用ＰＩＸＥ方法分析了满洲里－新巴尔虎右旗斑岩系列多金属矿床石英流体包裹体的液相多元素化学组分,其结果反映了地质矿化规律。该方法对于多金属矿床石英流体包裹体成分研究非常有用。结合其他包裹体研究,提出甲乌拉与直干布拉根矿床流体组分和成矿物理化学条件均不同,初步认为不存在同一矿化中心;还提出了查干布拉根矿床西矿段深部可能存在乌奴格吐山式斑岩型Ｃｕ矿床,应引起注意。  相似文献   

Response of hybrid isolation system during a shake table experiment of a full‐scale isolated building          下载免费PDF全文

Keri L. Ryan  Taichiro Okazaki  Camila B. Coria  Eiji Sato  Tomohiro Sasaki 《地震工程与结构动力学》2018,47(11):2214-2232

A full‐scale 5‐story steel moment frame building was subjected to a series of earthquake excitations using the E‐Defense shake table in August, 2011. For one of the test configurations, the building was seismically isolated by a hybrid system of lead‐rubber bearings and low friction roller bearings known as cross‐linear bearings, and was designed for a very rare 100 000‐year return period earthquake at a Central and Eastern US soil site. The building was subject to 15 trials including sinusoidal input, recorded motions and simulated earthquakes, 2D and 3D input, and a range of intensities including some beyond the design basis level. The experimental program was one of the first system‐level full‐scale validations of seismic isolation and the first known full‐scale experiment of a hybrid isolation system incorporating lead‐rubber and low friction bearings. Stable response of the hybrid isolation system was demonstrated at displacement demands up to 550 mm and shear strain in excess of 200%. Torsional amplifications were within the new factor stipulated by the code provisions. Axial force was observed to transfer from the lead‐rubber bearings to the cross‐linear bearings at large displacements, and the force transfer at large displacements exceeded that predicted by basic calculations. The force transfer occurred primarily because of the flexural rigidity of the base diaphragm and the larger vertical stiffness of the cross‐linear bearings relative to the lead‐rubber bearings.  相似文献   

Submarine slope–fan sedimentation in an ancient forearc related to contemporaneous magmatism: The Upper Cretaceous Izumi Group,southwestern Japan          下载免费PDF全文

Atsushi Noda  Daisuke Sato 《Island Arc》2018,27(2)

The Izumi Group in southwestern Japan is considered to represent deposits in a forearc basin along an active volcanic arc during the late Late Cretaceous. The group consists mainly of felsic volcanic and plutonic detritus, and overlies a Lower to Upper Cretaceous plutono‐metamorphic complex (the Ryoke complex). In order to reconstruct the depositional environments and constrain the age of deposition, sedimentary facies and U–Pb dating of zircon grains in tuff were studied for a drilled core obtained from the basal part of the Izumi Group. On the basis of the lithofacies associations, the core was subdivided into six units from base to top, as follows: mudstone‐dominated unit nonconformably deposited on the Ryoke granodiorite; tuffaceous mudstone‐dominated unit; tuff unit; tuffaceous sandstone–mudstone unit; sandstone–mudstone unit; and sandstone‐dominated unit. This succession suggests that the depositional system changed from non‐volcanic muddy slope or basin floor, to volcaniclastic sandy submarine fan. Based on a review of published radiometric age data of the surrounding region of the Ryoke complex and the Sanyo Belt which was an active volcanic front during deposition of the Izumi Group, the U–Pb age (82.7 ±0.5 Ma) of zircon grains in the tuff unit corresponds to those of felsic volcanic and pyroclastic rocks in the Sanyo Belt.  相似文献   

Mechanical properties and stress–dilatancy relationships of unsaturated soil under various cyclic loading conditions     

Tun Tun  Win  Sato  Tomotaka  Saito  Hirotaka  Kohgo  Yuji 《Acta Geotechnica》2020,15(7):1799-1813

Acta Geotechnica - Most studies investigating the effect of cyclic loading on soil properties have been conducted for saturated soils. Embankments such as fill dams, roads and railways are usually...  相似文献