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81.
We describe the present status of the project of the Taiwan Oscillation Network (TON) and discuss a scientific result using
the TON data. The TON is a ground-based network to measure solar intensity oscillations for the study of the solar interior.
Four telescopes have been installed in appropriate longitudes around the world. The TON telescopes take K-line full-disk solar
images of diameter 1000 pixels at a rate of one image per minute. The data has been collected since October of 1993. The TON
high-spatial-resolution data are specially suitable for the study of local properties of the Sun. In 1997 we developed a new
method, acoustic imaging, to construct the acoustic signals inside the Sun with the acoustic signals measured at the solar
surface. From the constructed signals, we can form intensity map and phase-shift map of an active region at various depths.
The direct link between these maps and the subsurface wave-speed perturbation suffers from the poor vertical resolution of
acoustic imaging. Recently an inversion method has been developed to invert the measured phase travel time perturbation to
estimate the distribution of wave-speed perturbation based on the ray approximation. This technique of acoustic imaging has
been used to image the far-side of the Sun that could provides information on space weather prediction.
The TON Team includes: Antonio Jimenez (Instituto Astrofisica de Canarias, Spain); Guoxiang Ai and Honqi Zhang (Huairou Solar
Observing Station, P.R.C.); Philip Goode and William Marquette (Big Bear Solar Observatory, U.S.A.); Shuhrat Ehgamberdiev
and Oleg Ladenkov (Ulugh Beg Astronomical Institute, Uzbekistan)
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
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An important but untested aspect of the lithopanspermia hypothesis is that microbes situated on or within meteorites could survive hypervelocity entry from space through Earth's atmosphere. The use of high-altitude sounding rockets to test this notion was explored. Granite samples permeated with spores of Bacillus subtilis strain WN511 were attached to the exterior telemetry module of a sounding rocket and launched from White Sands Missile Range, New Mexico into space, reaching maximum atmospheric entry velocity of 1.2 km/s. Maximum recorded temperature during the flight was measured at 145 degrees C. The surfaces of the post-flight granite samples were swabbed and tested for recovery and survival of WN511 spores, using genetic markers and the unique DNA fingerprint of WN511 as recovery criteria. Spore survivors were isolated at high frequency, ranging from 1.2% to 4.4% compared with ground controls, from all surfaces except the forward-facing surface. Sporulation-defective mutants were noted among the spaceflight survivors at high frequency (4%). These experiments constitute the first report of spore survival to hypervelocity atmospheric transit, and indicate that sounding rocket flights can be used to model the high-speed atmospheric entry of bacteria-laden artificial meteorites. 相似文献
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It is becoming increasingly clear that space activities can benefit from international cooperation, but concerns about national interests remain. This article examines the experience of the Inter-Agency Consultative Group (IACG), which achieved striking success in coordinating the efforts of the USA, the USSR, the European Space Agency and Japan to study Halley's Comet. Subsequently the IACG has undertaken a new project, focused on solar-terrestrial science, and further expansion could follow. However, tje group's success has depended on scrupulous respect for members' national autonomy, and so it is unlikely to herald the formation of a supranational space agency in the near future. 相似文献
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任少红 《长沙航空职业技术学院学报》2002,2(1):27-29
对陶行知先生的“教学做合一“的教育思想,教育史学界历来褒贬不一.在大力发展高等职业教育的现实视野下,应如何认识和理解“教学做合一“?本文在分析“教学做合一“的内涵并与杜威的“从做中学“进行比较的基础上,论述了“教学做合一“对高等职业教育教学建设的现实指导意义. 相似文献
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