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11.
H. Noda T. Terasawa Y. Saito H. Hayakawa A. Matsuoka T. Mukai 《Space Science Reviews》2001,97(1-4):423-426
‘The Japanese Mars probe, NOZOMI, is staying in the interplanetary space (1–1.5 AU) until its Mars’ orbit insertion scheduled
in early 2004. Every 16 months on this interplanetary orbit the spacecraft crosses around 1 AU the ‘gravitational focusing
cone’ of the interstellar helium, which are penetrating into the inner heliosphere under the solar gravity. During the first
crossing of the cone in the season of March–May 2000, we observed these helium particles after the solar wind pickup process
with an E/q type ion detector aboard NOZOMI. We have estimated the original temperature of the interstellar helium as 11 000 K.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
12.
Hideo Hanada Takahiro Iwata Qinghui Liu Fuyuhiko Kikuchi Koji Matsumoto Sander Goossens Yuji Harada Kazuyoshi Asari Toshiaki Ishikawa Yoshiaki Ishihara Hirotomo Noda Seiitsu Tsuruta Natalia Petrova Nobuyuki Kawano Sho Sasaki Kaori Sato Noriyuki Namiki Yusuke Kono Kenzaburo Iwadate Osamu Kameya Katsunori M. Shibata Yoshiaki Tamura Shunichi Kamata Yukihiro Yahagi Wataru Masui Koji Tanaka Hironori Maejima Xiaoyu Hong Jinsong Ping Xian Shi Qian Huang Yusufu Aili Simon Ellingsen Wolfgang Schlüter 《Space Science Reviews》2010,154(1-4):123-144
The Japanese lunar explorer SELENE (Kaguya), which was launched on September 14th, 2007, was the target of VLBI observations over the period November 2007 to June 2009. These observations were made in order to improve the lunar gravity field model, in particular the lower degree coefficients and the model near the limb. Differential VLBI Radio sources, called VRAD instruments, were on-board the subsatellites, Rstar (Okina) and Vstar (Ouna), and the radio signals were observed by the Japanese VERA (VLBI Exploration of Radio Astrometry) network, and an international VLBI network. Multi-frequency and same-beam VLBI techniques were utilized and were essential aspects of the successful observing program. Multi-frequency VLBI was employed in order to improve the accuracy of the orbit determination obtained from the phase delay from the narrow-band satellite signals, while the same-beam VLBI method was used to resolve the cycle ambiguity which is inherent in the multi-frequency VLBI method. The observations were made at three S-band frequencies (2212, 2218 and 2287 MHz), and one X-band frequency (8456 MHz). We have succeeded in correlating the recorded signals from Okina/Ouna, and we obtained phase delays with an accuracy of several pico-seconds at S-band. 相似文献
13.
The motion of a lure in water is investigated experimentally and numerically. The lure motion in water of a passing water tank is observed, and the periodic motion is/ound. From the Fourier analysis, it is found that the frequency with the largest amplitude in the lateral direction depends on the lip width of the lure. To understand the lure dynamics, a numerical simulation of the flow field around the lure is performed. The shape is measured using an X-ray computer tomography and converted into a voxel model. From visualization, it is found that vortex sheds from its lip correspond to the vibration frequency of the lure. 相似文献