1998 Vol. 18, No. 3

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INTERACTION BETWEEN MHD INTERMEDIATE SHOCKS
HU Xiaolong, HU Youqiu
1998, 18(3): 193-199. doi: 10.11728/cjss1998.03.193
Abstract(1893) PDF 424KB(805)
Abstract:
This paper discusses the interaction between MHD intermediate shocks. The main conclusions are as follows. The outcome of MHD intermediate shock merging consists of a reverse fast simple wave,a reverse slow simple wave or shock,a contact surface,a forward slow shock, and a forward fast shock, in which the reverse waves and the contact surface very weak.The outcome of MHD intermediate shock collision depends on the relative strength of the left and right shocks before collision. When the left shock is stronger,the outcome consists of a reverse fast shock,a reverse slow simple wave or shock,a negative contact surface,a forward slow simple wave, and a forward fast shock. On the contrary, the outcome becomes a reverse fast shock, a reverse slow simple wave, a positive contact surface,a forward slow simple wave or shock, and a forward fast shock.
THE HEMISPHERIC POWER INPUT AND HEIGHTINTEGRATED CONDUCTANCE
SHEN Changshou, ZI Minyun
1998, 18(3): 200-205. doi: 10.11728/cjss1998.03.200
Abstract(1872) PDF 395KB(1050)
Abstract:
An empirical model of height-integrated Pedersen and Hall conductance inferred from the TIROS-NOAA satellite dare are introduced and reviewed.The contours of both Pedersen and Hall conductance are drawn with the magnetic latitude-magnetic local time coordinates between 45°-90°GM and 0-24 MLT for discrete levels of particle precipitation. Similar contours of conductance controlled by solar irradiation in different seasons are also shown with same coordinates but for 9°-90°GM and 0-24 MLT. The internal relationship between the magnetosphere-ionosphere coupling and conductance model is investigated too.
OPTICAL-THERMAL EFFECT OF NOx EXHAUST PLUME IN LOCAL IONOSPHERE
MA Yanhua, ZHAO Hua
1998, 18(3): 206-212. doi: 10.11728/cjss1998.03.206
Abstract(1824) PDF 468KB(852)
Abstract:
A spherical expansion approximation is used to simulate transient maximal radiance of NO gas cloud release and it is time-dependence under a pressure-balancing condition.It is found that if NO gas of 5mol was released at an altitude of 110km the cloud produces luminescent spherical trails as medium intensive aurora However, the cloud brightness descends hastily at 140km. The temperature's decline in the local atmosphere due to a NO2 gas release in F-region was also simulated.The simulation is completed for 190 and 250km altitudes, 50 and 500mol released amount for both day and night time. A distinct cooling effect is perceptible or bulk of NO2 release at lower F-region at night
THE NONLINEAR PROPAGATION OF GRAVITY WAVE PACKETS IN A NONISOTHERMAL AND COMPRESSIBLE ATMOSPHERE
ZHANG Shaodong, YI Fan
1998, 18(3): 213-21. doi: 10.11728/cjss1998.03.213
Abstract(2125) PDF 453KB(1105)
Abstract:
By using two-dimentional Full-Implicit-Continuous-Eulerian(FICE)scheme,a numerical simulation of nonlinear propagation of a Gaussian gravity-wave-packet in the compressible and nonisothermal atmosphere is carried out,and a quantitative comparison with the propagation in an isothermal atmosphere and the linear gravity wave theory under the WKB approximation is also presented.The numerical analysis shows that for an initially given upgoing gravity-wave-packet although affected by the nonlinear interaction and the inhomogeneity of background temperature, during the propagation, the whole wave packet and the wave-associated energy keep moving upward,while the wave front moving downward. Affected by the inhomogeneity of the background temperature, the shape of the wave packet alters more significantly than in isothermal case, and there occurs wave breaking at the downstream region of the wave packet. The nonlinear energy propagation path of the gravity-wave-packet shows evident difference from the ray path derived from the linear ray theory under the WKB approximation,this indicates that it is not feasible to describe quantitatively the nonlinear propagation of gravity-wave-packet in a nonisothermal atmosphere by using the linear gravity wave theory under the WKB approximation.
THE SUN-EARTH CONNECTION EVENT OF JANUARY 6-11, 1997
GAO Yufen, WANG Jialong, XIAO Zuo
1998, 18(3): 222-227. doi: 10.11728/cjss1998.03.222
Abstract(2225) PDF 418KB(658)
Abstract:
The Paper presents the features of disturbances of solar wind and interplanetary as well as the magnetic storm recorded at the geomagnetic network in China during the Sun-Earth connection event of January 6-11, 1997. The magnetic storm-rin currentconvection electic fields are sturdied using the data. Results show that the beginning of the main phase is formed maily by convection electric field driven by IMF Bs. The convection electric fields play very important roles during the main phase evolution, but the effects are different at different stages.
PREDICTION OF MAJOR STORMS BY USING NEURAL NETWORKS
ZHOU Xiaoyan, PAN Xinping, YANG Yiping
1998, 18(3): 228-234. doi: 10.11728/cjss1998.03.228
Abstract(2077) PDF 467KB(1698)
Abstract:
Good prediction results for geomagnetic indices have been obtained with the use of artificial intelligent(AI)technique,especially by the neural networks.While a common Problem is how to increase the advance time of the prediction.It is true that the earlier of the prediction, the less possibility to predict the detail of an impending event.Therefore threshold prediction should be also a very helpful and useful method for early time prediction when forecasting the occurrence of the events which bring disaster on the cormmunication,power transmission and satellite life etc. Threshold prediction means the predicted events are over a threshold,such as-120nT. In this paper BP model of neural networks is used to predict the major storms 4 hours ahead, with the minimum of Dst less than-120nT. The inputs are 13 solar wind parameters and geomagnetic AE and Dst.The ought is I for major storms or 0 for non major storms. The results show that the threshold prediction by neural networks can give accurate prediction for major storm occurrence.
THE ORIGIN OF EXTRATERRESTRIAL IMPACT SPHERULES──WITH THE REFERENCE TO KTB SPHERULES
ZOU Yongliao, OUYANG ziyuan, WANG Shijie, LI Chunlai
1998, 18(3): 235-241. doi: 10.11728/cjss1998.03.235
Abstract(2024) PDF 494KB(1112)
Abstract:
The chemical, mineralogical,structural, morphological characteristics of KTB spinelbearing spherules,and the experimental results of meteorite ablation,are suggestive of that some of KTB spherules derived from projectile ablation debris,some from condensates of impact vapor.More than these,some KTB spherules are of the characteristics in compositions similar to that of condensates of impact vapor but in structures similar to that of projectile ablation debris suggesting that these spherules might be derived from another mechanism.
AUTOMATIC OUT-SIGHT TRACING FOR BALLOON-BORNE HIGH ENERGY ASTRONOMICAL TELESCOPE
LIN Baojun, QU Weizhen, WU Bobing, ZHANG Xiyuan, LI Tipei, XUE Jingxuan
1998, 18(3): 242-246. doi: 10.11728/cjss1998.03.242
Abstract(2101) PDF 267KB(1365)
Abstract:
Based on the previous HAPI-4 control system,a balloon-borne attitude pointing control system digitalization is implemented by using 16 bits 80C196 single-chip processor for the first time. Meanwhile, by means of Global Positioning System(GPS), high precision Positioning and absolute time calibration is fulfilled. Also,a small,high density tape recorder is used as the balloon-borne data flow storage,and out-sight telemetry and teleconmmand is implemented by using INMARSAT system.Thus,a new balloonborne high energy astronomical telescope control system is brought about.
OBSERVATION OF IONOSPHERIC DISTURBANCES WITH GPS BEACONS
WAN Weixing, NING Baiqi, YUAN Hong, LI Jingnian, LIANG Jun, LI Libin
1998, 18(3): 247-252. doi: 10.11728/cjss1998.03.247
Abstract(2177) PDF 363KB(1207)
Abstract:
The GPS method is rarely used in the investigation of ionospheric disturbances because of the movement of the observation point which leads to the mixture of both spatial and temporal changes of the observed total electron content(TEC). The present work proposes a new experiment method to modify the effects of the montion of observation points by the observation of a short baseline array of GPS receivers.The experimental results show that the wave parameters of the ionospheric disturbances derived from the observation of a short baseline GPS array are of high precision and reliable. The main advantage of the new experiment method is that the short baseline GPS array may used to observe ionospheric disturbances in a large range.
STUDY ON SEU OCCURRED ON BOARD OF SEVERAL SPACE SHUTTLES
GU Shifeng, ZANG Zhenqun, SHI Liqin, WU Zhonghua
1998, 18(3): 253-260. doi: 10.11728/cjss1998.03.253
Abstract(2170) PDF 466KB(1508)
Abstract:
In this paper, Single Events Upset(SEU) encountered by five low altitude orbit space shuttles with different inclinations and different altitudes launched in 1991 are investigated.The result shows that a number of SEUs can occur even in auroral area or south Atlantic abnormal area,threatening the security of space shuttles. Some Pertinent results and conclusions are obtained.
EFFECT OF -6°HEAD-REST ON THE T LYMPHOCYTE AND ENDOCRINE SYSTEM
WANG Tao, WEN Xiulan, YANG Guanghua, HU Ring, SI Shaoyan, XIANG Ciulu
1998, 18(3): 261-264. doi: 10.11728/cjss1998.03.261
Abstract(2192) PDF 298KB(634)
Abstract:
This paper is to investigate the effects of the simulated weightlessness in a minus 6°head-down bed-rest condition(SW) on the T lymphocyte proliferation stimulated with PHA and on the T lymphocyte subsets.The changes of growth factor(GH), adrenocoticotrophic hormone(ACTH),cotisol(CT)are also observed.The results show that the T lymphocyte proliferation decreased significantly (P<0.05) two days after SW,and recover to normal six days after SW. The CD3, CD4, and CD8 positive T lymphocyte appeared no obvious depression after SW.The GH concentration in plasma increased significandy(P<0.01) two days after SW,and recover tO normal six days after SW.The ACTH concentration in plasma tend to increase tWo days after SW,it seem to decrease six days after SW.The CT concentration in plasma increase significantly(P<0.05) and recover to normal six days after SW.The conclusion is that the dysfunction of T lymphocyte may be caused by the perturbations of endocrine system.
SOME ADVANCES IN SMALL SATELLITE TECHNOLOGY
YU Dejiang
1998, 18(3): 265-270. doi: 10.11728/cjss1998.03.265
Abstract(1912) PDF 363KB(1548)
Abstract:
Some advances in structure,power supply and operation system of small satellites are reported and reviewed.The emphasis is put on new materials,devices and techniques in the stature,and new conceptions and schemes for the autonomous operation system.
THE ASSOCIATIVE PROCESSES OF SOLAR MICROWAVE BURSTS WITH ENERGETIC PROTONS
LI Chunsheng, FU Qijun
1998, 18(3): 271-278. doi: 10.11728/cjss1998.03.271
Abstract(1971) PDF 535KB(835)
Abstract:
In the paper,it is shown that neither type Ⅱ nor meter-wave type Ⅳ but intense microwave bursts are nearly always associated with energetic protons by data analysis of recent observations of solar radio bursts and associated γ-ray emissions/proton events.The result is contrary to the previous long-held views.The microwave bursts associated with energetic protons can be divided into two classes:impulsive and type Ⅳμ bursts.The former is associated with much more happed or interacting protons than the escaping ones,but the latter often associated with more escaping protons. Furthermore,the efficient acceleration processes for the different cases in solar microwave bursts and the reasons why the intense microwave bursts are nearly always associated with energetic protons are also discussed.
THE TIME VARIATION CHARACTERISTICS OF SOLAR MICROWAVE IMPULSIVE EVENT
XU Fuying, WU Hongao
1998, 18(3): 279-283. doi: 10.11728/cjss1998.03.279
Abstract(1831) PDF 312KB(870)
Abstract:
During the Periods of January 1988-December 1989,fifteen solar impulsive events reported by Berne University, Switzerland are analysed in this paper.And three main characteristics,impulsiveness,asymmetry and variation of width at half power maximum with frequency on the bine profiles of events are found.They may be interpreted qualitatively by means of continuous injection of nonthermal electrons and a nonuniform source region model.
THE ASYMMETRICAL DISTRIBUTION OF THE X-RAY FLARES WITH Imp≥M1.0 AT THE MAXIMUM PERIOD OF THE 22nd SOLAR CYCLE
LI Kejun
1998, 18(3): 284-288. doi: 10.11728/cjss1998.03.284
Abstract(1939) PDF 400KB(690)
Abstract:
The data of the X-ray flare events with importance≥M1.0 at the maximum period of the 22nd solar cycle are used to investigate the feature of their spatial distribution. The results show that there is a north-south asymmetry in their spatial distribution and the sign of asymmetry may be changed at the maximum year or one year before or after. Although one solar hemisphere totally dominates in a solar cycle, the other may dominates in the maximum year of the solar cycle or one year before or after. Correlation between asymmetry and solar activities are discussed too.

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