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The correlation of flare's location on solar disc and the sudden increase of total electron content

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chinese Science Bulletin 2002年第1期47卷 82-85页

作者： ZHANG Donghe, XIAO Zuo & CHANG QingDepartment of Geophysics, Peking University, Beijing 100871, china qingdao research center, china research Insitute of radio-wave propagation, qingdao 266071, china Department of Electronic Engineering, Beijing Universit Department of Geophysics Peking University Beijing China qingdao research center China Research Insitute of Radio-wave Propagation Qingdao China Department of Electronic Engineering Beijing University of Aeronautics and Astronautics Beijing China

The correlation of flare’s location on solar disc with the value of sudden increase of total electron content is analyzed with flare’s parameters observed by GOES satellite from 1997 to 1999 and total electron content derived from GPS data observed by international GPS Service for Geo-dynamics. It is found that, besides the flare’s maximum X-ray flux, flare’s location on solar disc has some relation with the value of SITEC during the flare. The ionospheric response to a flare with a smaller maximum X-ray flux and nearer angular distance to the Sun’s central meridian line may be stronger than that of the flare with a larger maxi-mum X-ray flux and far angular distance. To the flares with the same class of maximum X-ray flux, the nearer the angu-lar distance to the Sun’s meridian, the stronger the ionospheric response.

关键词： flare SITEC GPS.

SAR IMAGING SIMULATION OF HORIZONTAL FULLY TWO-DIMENSIONAL INTERNAL waveS

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Journal of Hydrodynamics 2006年第3期18卷 294-302页

作者： SHEN Hui HE Yi-Jun institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China Graduate School of the chinese Academy of Sciences Beijing 100039 China

Based on the research of Lynett and Liu, a new horizontal fully two-dimensional internal wave propagation model with rotation effect was deduced, which can be used to simulate the characteristics of internal waves in a horizontal fully two-dimensional plane. By combining the imaging mechanism of Synthetic Aperture Radar（SAR）, a simulation procedure was fatherly acquired, which can simulate the propagation characteristics of oceanic internal waves into SAR images. In order to evaluate the validity of the proposed simulation procedure, case studies are performed in South china Sea and results from simulation procedure are analyzed in detail. A very good consistency was found between the simulation results and satellite images. The proposed simulation procedure will be a possible foundation for the quantitative interpretation of internal waves from fully two-dimensional satellite images.

关键词： oceanic internal waves imaging simulation,Synthetic Aperture Radar (SAR)

Representation of microscale ocean wavenumber spectrum correct to the second order

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Science china Earth Sciences 2005年第4期48卷 549-554页

作者： YUAN Yeli2 & HUA Feng1,2,3 1. institute of Oceanology, chinese Academy of Sciences, qingdao 266071, china 2. Key Laboratory of Marine Science and Numerical Modeling, State Oceanic Administration, qingdao 266061, china 3. Graduate School of the chinese Academy of Sciences, Beijing 100039, china Key Laboratory of Marine Science and Numerical Modeling State Oceanic Administration Qingdao China institute of Oceanology Chinese Academy of Sciences Qingdao China Graduate School of the chinese Academy of Sciences Beijing China

In this paper, the analytical representations of four wave source functions in high-frequency spectrum range are given on the basis of ocean wave theory and dimensional analysis, and the perturbation method is used to solve the governing equations of ocean wave high-frequency spectrum on the basis of the temporally stationary and locally homogeneous scale relations of microscale wave. The microscale ocean wavenumber spectrum correct to the second order has an explicit structure, its first order part represents the equilibrium between dif- ferent source functions, and its second order part represents the contribution of microscale wave propagation.

关键词： temporally stationary and locally homogeneous, source function in high-frequency spectrum range, microscale ocean wavenumber spectrum.

EXPERIMENT OF SHORT wave COMMUNICATION AND THE INVESTIGATION OF THE propagation BEARINGS BETWEEN THE GREAT WALL STATION AND XINXIANG

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chinese Journal of Polar Science 1990年第1期1卷 67-74页

作者： Sun Xianru and Li Zhongqin china research institute of radio wave propagation, Xinxiang 453003

The distance from the Great Wall Station (62.2°S, 58.9°W) to Xinxiang (35.3°N, 113.8°E) is 16981 km. The path passes through the polar cap absorption region and the auroral absorption zone, and it is across the equator.In this paper firstly the effects of short wave communication and usable time blocks and frequency ranges between the Antarctic Great Wall Station and Xinxiang from December 1985 to March 1986 are introduced. The comparison between the usable frequency ranges with the estimated MUF is made. The upper limit of frequency ranges of communication along the short great circle path basically agrees with the MUF but there is difference between them along the long great circle path.Secondly, the result of the propagation bearings experiment in January to February 1986 is introduced in more detail, The propagation along the great circle path from the Great Wall Station to Xinxiang is the main propagation mode. But the propagation along non great circle paths occurs at times between Great Wall Station and Xinxiang. The non great circle path propagation varies with time because the ionospheric absorption and other conditions which support the non great circle path propagation are the function of the time. So the courses of the non great circle path propagation may be different in the different time. The mechanism of the constructing non great circle path propagation has been analysed. We preliminarily think the main cause of propagation along non great circle path is the ground scatter. The stronger radialization of the side lobes of the antenna and the less absorption of the ionosphere contribute to forming non great circle path propagation.

关键词： Communication experiment Great Wall Station Xinxiang Station propagation bearings.

Statistical analysis and model of spread F occurrence in china

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Science china(Technological Sciences) 2010年第6期53卷 1725-1731页

作者： XU Tong1,WU ZhenSen2,HU YanLi1,WU Jian1,SUO YuCheng1 & FENG Jian1 1 National Key Laboratory of Electromagnetic Environment,china research institute of radiowave propagation,qingdao 266107,china 2 School of Science,Xidian University,Xi’an 710071,china National Key Laboratory of Electromagnetic Environment China Research Institute of Radiowave Propagation Qingdao China School of Science Xidian University Xi’an China

The spread F data obtained over Lanzhou (36.1°N,103.9°E),Chongqing (29.5°N,106.4°E) and Haikou (20.0°N,110.3°E) of china during the period from 1978 to 1997 are used to analyze the occurrence *** statistical results show that the post midnight spread F occurrence is maximum during the summer solstice months of the lower solar activity period,while post sunset spread F is dominant in equinoxes of higher solar activity period over Haikou *** Chongqing and Lanzhou stations,spread F mostly occurs at post midnight and relates negatively with solar *** regression method and Fourier expansion,the preliminary single-station model of spread F occurrence is established and the accuracy of the model is evaluated.

关键词： spread F solar cycle variation seasonal variation empirical model

Response characteristics of array lateral logs and their primary inversion in reservoirs with fracture-induced anisotropy

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Petroleum Science 2011年第1期8卷 11-16页

作者： Deng Shaogui Fan Yiren Li Zhiqiang Sun Qingtao School of Geo-resources ＆ Information China University of PetroleumShandong 266555China china research institute of radio wave propagation Henan 453003China

In order to identify fractured reservoirs and determine their fracture parameters with a high definition array laterolog,we built a fracture-induced anisotropic formation model with a parallel fracture *** three-dimensional finite element method is used to simulate the responses of the array laterolog,and then the primary inversion method is *** simulation shows that when the fracture spacing is small,the array laterolog response of the fracture group is the same as that of a formation with macroscopic electrical *** apparent resistivity of the array laterolog is approximately inversely proportional to fracture *** anisotropy depends on the fracture porosity in the fractured formation,which accordingly results in response variation of the array *** higher the fracture dip,the larger the apparent *** the fracture dip is low the difference between the deep and shallow apparent resistivities is small,and when the dip is high the difference turns out to be *** fracture parameters were inverted using the Marquardt non-linear least squares *** results,both fracture porosity and dip show a good match with parameters in the actual formation *** will promote the application of the array laterolog in evaluating fractured reservoirs.

关键词： Fracturing anisotropic reservoir fracture dip fracture porosity array laterolog

Incoherent Scatter Radar in china

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Incoherent Scatter Radar in China

Technology study of foF2 forecasting in the ionospheric disturbance

第十一届全国日地空间物理学术讨论会

作者： Wu Yong-hong Wu Jian Huang Chang-li Wu Zhen-sen (china research institute of radiowave propagation qingdao 266071, National Key Lab of Electromagnetic Environment Beijing 102206, Xidian Universiy Xi''an 710071) (china research institute of radiowave propagation qingdao 266071, National Key Labortory of Electromagnetic Environment Beijing 102206) (china research institute of radiowave propagation qingdao 266071) (Xidian Universiy Xi''an 710071)

＜正＞Incoherent scatter radar is a very powerful ground measurement device which can measure upper atmosphere parameters such as electron temperature, electron density, ion temperature, ion mass, etc. The reflection signal of the ionosphere is much stronger than the scatter signal of it, so the working frequency of the incoherent scatter radar is above VHF. There is no incoherent scatter radar in Asia and the Pacific at present. Constructing an incoherent scatter radar in low latitude of our country will make our country become one of several counties in the world which have this kind of radars. And it is very important to accelerate space physics research in our country.

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Technology study of foF2 forecasting in the ionospheric dist...

第十一届全国日地空间物理学术讨论会

作者： Danjun Chen, Jian Wu, Xianyi Wang (china research institute of radiowave propagation, qingdao, 266071) (National Key Laboratory of Electromagnetic Enviroment, china research institute of radiowave propagation, Beijing 102206)

＜正＞The ionosphere of the Earth is an especially complicated and nonlinear system, which is controlled by the solar activities and the conditions of the geo-space. The ionosphere is important to the Earth-space communication systems, especially the ionospheric disturbances leads to deterioration or invalidation of the operational performance of the HF or Earth-space communication systems. Based on the ionosonde foF2 data and Ap index, The Artificial Neural Network （ANN） Technique will be applied to the ionospheric foF2 forecast during periods of the disturbance happens. To optimize input of network and obtain better forecasting result, this paper analyze first relative correlations between the ionospheric parameter foF2 and the geomagnetic activity indices Ap to reflect better relations. Then the BP algorithm will be used to train the network and ionospheric critical frequency foF2 will be forecasted one hour in advance.

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短波电路最高可用频率准实时预报方法

通信学报 1991年第6期12卷 103-105页

作者：黄德耀中国电波传播研究所

本文提出了利用MUF自身的变化规律来作准实时预报的方法。

关键词：短波电路频率准实时预报法 MUF