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1.
2.
The behaviour of the flare in the period of enhancement and maximum of hard X-ray, microwave and decimetric type IV continuum is analysed. The elongation of the H ribbons and microwave source disclose that the energy release site was shifting through a system of loops with a velocity less than 200 km s-1, and that the energy was carried down the field lines with a velocity of about 1000 km s-1, implying the thermal conduction front mechanism of energy transport. Several processes of energy release are considered and it is concluded that an explanation in terms of succeeding interactions of neighbouring loops, involving fast reconnection of their poloidal components is in best agreement with the observations.Proceedings of the Second CESRA Workshop on Particle Acceleration and Trapping in Solar Flares, held at Aubigny-sur-Nère (France), 23–26 June, 1986. 相似文献
3.
On the coronograph spectrophotographic records taken on 31.372 UT, August 1979, some faint emission features were found which can be ascribed to Siii and Niii. These emissions were obviously a transient phenomena which were detected only 10 hr after the supposed fall of Comet 1979 XI in the Sun's photosphere. It cannot be excluded that the appearance of Si and Ni lines was triggered by the evaporation of dust particles with a high abundance of heavier elements in the solar corona. This assumption is also supported by intensity distribution of the Fex coronal line around the Sun's limb. The maximum coincide with the position angle of the projected path of the comet. 相似文献
4.
The underwater acoustic image transmission system based on the high-speed DSP device TMS320C549 has been studied.We use Goertzel algorithm for source decoding and MFSK for modulation.Turbo code is used for channel coding and decoding.The purpose is to implement underwater video image data transmission. 相似文献
5.
最近,由欧盟(则资助的研究项目(Parforce)研究人员发现了海洋藻类与气候变化之间的联系。项目研究人员发现,从海洋藻类及浮游生物释放的碘蒸汽,在海面上浓缩,形成对抗地球变暖的悬浮微粒。此悬浮微粒对地球气候变化及降 相似文献
6.
A comparative analysis of spotless and spot group flares recorded at Hvar and Kanzelhöhe Observatories during the 21st cycle of solar activity is presented. The rate of occurrence of two-ribbon flares was found to be significantly higher for the spotless flares. In comparison with spot group flares of corresponding H importance, the soft X-ray peak values have been systematically lower for the spotless flares. The highest peak values and the energy released in soft X-rays was found for flares with a H ribbon protruding over a major spot umbra. It was found that the effective plasma temperatures in spotless flares have been considerably lower than the temperatures in spot group flares. 相似文献
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以西安钟楼的精细测绘与三维建模为工程实例,利用三维激光扫描技术对钟楼进行精细扫描测量,构建了准确翔实的钟楼三维模型,绘制了楼体详尽的纵横剖面、立面等二维图,为钟楼修缮和存档提供了准确的测量数据、图形、图像及模型.此外,通过该案例,详细分析了三维激光扫描技术在中国古建筑测绘应用中的技术优势与不足. 相似文献
9.
The paper presents an analysis of the coronal data of emission line 530.3 nm. The analysis was carried out with data recorded at the coronal station of Lomnický tít for the period 1965–1976. Up till now the observed time and latitudal changes of the shape of the corona as well as the existence of two maxima have been fully proved. The development of intensities has, in many cases, different characters in the southern and northern hemispheres. Apart from this, the third increase of intensities in the course of the cycle was observed nearly at all latitudes in the coincidence with sunspot numbers in 1974–1975 years. The maximum of intensities of this impulse of activity was observed at latitudes around 60° in both hemispheres. 相似文献
10.
The interrelations of the latitudinal distribution of the coronal green emission maxima, maximal numbers and areas of prominences, magnetic fields, sunspots, and polar faculae in the 20th and 21st sunspot cycles have been investigated. It is again demonstrated how the behaviour of all studied data depends on their heliographic latitude. In the polar zone, well separated from the equatorial we observe following polarity magnetic fields transported only polewards, while the equatorial zone is occupied mostly by leading polarity fields, developed there, moving equatorwards, and crossing the equator to the other hemisphere with the new cycle during the minimum of sunspot activity.This magnetic field distribution is well emphasized by the places of maximal occurrence of prominences and by the distribution of coronal green emission maxima which also differ in dependence on latitude.The question of identifying the first and last evolutionary stages of an extended cycle of activity is discussed and the existence of a magnetic activity cycle lasting 15–17 years is suggested. 相似文献