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    25 February 1993, Volume 13 Issue 01 Previous Issue    Next Issue
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    SPATIAL SPECTRUM ESTIMATION ALGORITHM AND CHANNEL MISMATCHING
    Luo Lichun (China Electronic System Engineering Company Special Electronic Division,Beijing)
    1993, 13 (01):  . 
    Abstract ( 2064 )   Save
    Channel mismatching has been regarded as a major obstacleon the way toward DF for spatial spectrum estimation by now.This paperproves the opinion wrong,Spatial spectrum estimation algorithm is ableto eliminate the effect of channel mismatching.A method of estimatingthe channel phase is given.The work of this paper shows that it is nottoo difficult or expensive for spatial spectum estimation to be a practicalDF method at present.
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    THE EFFECT OF THE REFLECTOR SHAPE PARAMETERS ON CROSS-POLARZATION
    Wang Wutu (Xi'an Space Radio Technology Institute)
    1993, 13 (01):  . 
    Abstract ( 1414 )   Save
    On the basis of design idea of mechanic-electrical unifica-tion for reflector antennas,this paper investigates the effects of the reflec-tor shape parameters on crosspolarization,and gives some reasonablecriteria of the structural design for reflector antennas.
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    A METHOD OF DETECTING NATURAL CALAMITIES ON EARTH
    Deng Zhenkun (Center for Space Science and Applied Research,Academia Sinica,Beijing)
    1993, 13 (01):  . 
    Abstract ( 1567 )   Save
    The purpose of this paper is to compare practically the dif-ferences of radiation temperatures between two methods,one is by recordingthe thermal status of the Earth and its atmosphere as a whole by a radia-tive spot source,and the other is by considering the Earth as a surfacesource by dividing it into several hundreds belts.We measure the tempe-rature changes of the sun and the cosmic environment respectively to get the knowledge of the thermal status of the Earth surface and its atmos-phere and also get the information about energy transpotation from the sunto the Earth or the cosmic space,thus we could study the thermal effectsreflected on the Earth by large scale terrestrial catastrophic events,such asvolcanic eruptions,earthquake calamities,climatic changes etc.,We detectthe dissipative structure of the Earth in space under the non-balancingthermal conditions(in the solar system,the solar temperature is 6000K;on the Earth the temperature is 300K and the temperature of the spacebackground is 3K)and study the auto-collected and auto-organizedphenomena under this status of physical mechanics events(the generationprocess of catastrophic events on the Earth),therefore we can establisha new branch of learning which is called non-balanced space thermody-namics and make it as an experiment science.The emphasis of this paperis to introduce the detecting methods used for above purposes and thefuture prospect of application.
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    DEGRADATION OF MATERIAL PROPERTIES AND DAMAGE ASSESSMENT FOR LARGE SPACE STRUCTURES
    Zhuo Shujun (National University of Defence Technology,Changsha)
    1993, 13 (01):  . 
    Abstract ( 1627 )   Save
    In this paper,the special themes which include effect ofdegradation of material properties on the dynamic response of largespace structures(LSS)and damage assessment for LSS have been dealtwith.This damage is usually observed in fibrous composite media.Delicatestudies implemented on representative space truss structures indicate thatdegradation of material properties will result in a reduction of naturalfrequencies and may have important effects on the mode shapes.A theoryfor assessing the occurrence,location,and extent of potential damageusing on-orbit response measurements is presented.A MAST truss is usedas an example.The damages to the structural system for the sampleproblem have been identified and the extent of the damage quantified.
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    EFFECTS OF Es ON OTHR PROPAGATION
    Li Yuhui (China Research Institute of Radiowave Propagation)
    1993, 13 (01):  . 
    Abstract ( 1539 )   Save
    The general characteristics of Es is described in this paper.By the calculation of Es field strength of the reflection midpoint betweenXinxiang and Jiuquan,the influence of Es on the skywave OTH-B radaris discussed.
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    MANAGEMENT OF INTERFACE DATA IN SATELLITE DEVELOPMENT
    Yang Weiyuan (CAST)
    1993, 13 (01):  . 
    Abstract ( 1667 )   Save
    In the process of satellite development,11 types of InterfaceData Sheets(IDS)may be used in order to improve the management ofinterface data of satellite equipment.They are.1.Machanical characte-ristics;2.Equipment scheme;3.Thermal characteristics;4.Thermalscheme;5.Electrical power;6.Interface electrical characteristics;7.Electrical block diagram;8.List of connectors;9.Pin assignments ofconnectors;10.List of telemetry;11.List of telecommands.They containall the data representing full interface characteristics of equipment.Bythem,strict configuration management may be reached.This paper presentsthe contents of these data sheets and the problems that may be encounteredin use.
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    TECHNIQUES OF REALIZING 3D MODELED ANIMATION FOR SPACE VEHICLE BASED ON CAD SYSTEMS
    Lin Baozhen (Beijing Institute of Satellite Information Engineering) Yang Siyi (The Institute of Computing Technology,Academia SINICA)
    1993, 13 (01):  . 
    Abstract ( 1568 )   Save
    This paper firstly demonstrates the possibility of realizing3D object motion control methods and their applications based on CADsystems,and then analyzes also the two 3D animation examples for spacevehicle,which are done by key frame technique and algorithms of con-trolling motion.Motion simulation on Euclid-IS system is also introduced.Finally a summary of works is presented.
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    EFFECTS OF SEVEL KINDS OF CHINESE HERB MEDICINES ON RABBIT EAR'S MICROCIRCULATION AND BLOOD RHEOLOGY DURING SIMULATED WEIGHTLESSNESS
    Shen Xianyun Xiang Qiulu Meng Jingrui (Institute of Space Medico-Engineering,Beijing)
    1993, 13 (01):  . 
    Abstract ( 1793 )   Save
    The changes of blood circulation during weightlessness(WL)are simular to the changes of blood-stasis called by Chinesemedicine.So it may be a good method to improve the state of blood cir-culation during WL by using Chinese herb medicine.In this experiment,the effects of four kinds of Chinese herb medicine,which are salviamiltiorrhiza bge+astragalus mongholicus bge(SM-AM),ligusticum walli-chii fanch(LWF),Guan Xin-2(GX-2)and anisodine(AS),on rabbit ear'smicrocirculation and blood rheology in simulated WL were compared.The results showed that the four kinds of Chinese medicines all hadthe effects to improve the blood circulation of rabbit under simulatedWL and the order was SM-AM>LWF>GX-2>AS,and also showed thatthe better dosage of SM-AM was 15g/kg,and the better dosage of LWFwas 10g/kg.
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    RESEARCH ON FRICTION TORQUE OF DISPIN ANTENNA MACHANISM BEARINGS
    Wang Ling Huang Kewei Yang Kunyuan (Lanzhou Institute of Physics)
    1993, 13 (01):  . 
    Abstract ( 1737 )   Save
    This paper describes that in atmosphere friction torque ofC7046112 bearings varied with axial load,rotational speeds,ball numberand lubricant.The test results showed that relations between bearingsaxial load and friction torque are not monotone increasing function.Theyare periodic function with maximam value and minimum value.Test re-sults are discussed also.The DZS—1 preload dynamic characteristic air-floating test equipmentis also introduced in this paper.
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    TWO DESIGNS OF TEST METHOD FOR MATERIALS OUTGASSING ACCELERATION PROCESS
    Wang Xianrong (Lanzhou Institute of Physics)
    1993, 13 (01):  . 
    Abstract ( 1590 )   Save
    In this paper,two concepts—spacecraft materials outgassing acceleration test and acceleration factor are described.The relationshipsbetween acceleration factor and different temperature outgassing state,between acceleration factor and outgassing time in different temperaturestate are discussed and given out.Two kinds of acceleration test methodsare designed.They are temperature changing test method and common testmethod.To verify the test designs,practical outgassing acceleration testswere taken using the former design upon some spacecraft materials,andthen their test results and gotten data were compared with 6500 hour non-acceleration test process of same materials.The conclusion confirms theoutgassing acceleration test methods designs.Some test data,experimentalprocess and results,concerned tables and figures are included in the paper.
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    STUDY ON WEIGHT-LIGHTENING MIRROR FOR SPACE REMOTE SENSING INSTRUMENTS
    Yang Bingxin (Beijing Institute of Space Machine and Electricity) Song Yougui Wang Youren (Changchun College of Optics and Fine Mechanics)
    1993, 13 (01):  . 
    Abstract ( 1617 )   Save
    The weigh-lightening of reflecting mirror is one of the impor-tant technical methods for the weigh-lightening of space remote sensinginstruments.This article expounded the significance of the weigh-lighteningof reflecting mirror,the selection of the reflecting mirror material,thestructural form and design requirements of the weigh-lightening of the glassreflecting mirror,the design scheme and the calculation.It also brieflyintroduced the results of temperature experiment.
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    TWO-WAY RANGING AND RANGING RATE SYSTEM USING THREE FREQUENCIES FOR PRECISE ORBIT DETERMINATION
    Tai Ping (Beijing Institute of Spacecraft System Engineering)
    1993, 13 (01):  . 
    Abstract ( 1600 )   Save
    To improve the precision of satellite tracking is an importantproblem,and people hope to research and resolve it for a long time.Thispaper,based on the developing of tracking system,presents a way whichcan be used for precise tracking and orbit determination of a satellite.
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