|
|
|
题名
|
作者
|
年代
|
出处
|
被引量
|
| 1 | Orbit determination for Chang'E-2 lunar probe and evaluation of lunar gravity models显示文摘The Unified S-Band(USB) ranging/Doppler system and the Very Long Baseline Interferometry(VLBI) system as the ground tracking system jointly supported the lunar orbit capture of both Chang'E-2(CE-2) and Chang'E-1(CE-1) missions.The tracking system is also responsible for providing precise orbits for scientific data processing.New VLBI equipment and data processing strategies have been proposed based on CE-1 experiences and implemented for CE-2.In this work the role VLBI tracking data played was reassessed through precision orbit determination(POD) experiments for CE-2.Significant improvement in terms of both VLBI delay and delay rate data accuracy was achieved with the noise level of X-band band-width synthesis delay data reaching 0.2-0.3 ns.Short-arc orbit determination experiments showed that the combination of only 15 min's range and VLBI data was able to improve the accuracy of 3 h's orbit using range data only by a 1-1.5 order of magnitude,confirming a similar conclusion for CE-1.Moreover,because of the accuracy improvement,VLBI data was able to contribute to CE-2's long-arc POD especially in the along-track and orbital normal directions.Orbital accuracy was assessed through the orbital overlapping analysis(2 h arc overlapping for 18 h POD arc).Compared with about 100 m position error of CE-1's 200 km 200 km lunar orbit,for CE-2's 100 km 100 km lunar orbit,the position errors were better than 31 and 6 m in the radial direction,and for CE-2's 15 km 100 km orbit,the position errors were better than 45 and 12 m in the radial direction.In addition,in trying to analyze the Delta Differential One-Way Ranging(DOR) experiments data we concluded that the accuracy of DOR delay was dramatically improved with the noise level better than 0.1 ns and systematic errors better calibrated,and the Short-arc POD tests with DOR data showed excellent results.Although unable to support the development of an independent lunar gravity model,the tracking data of CE-2 provided evaluations of different lunar gravity models through POD.It is found that for the 100 km 100 km lunar orbit,with a degree and order expansion up to 165,JPL's gravity model LP165P did not show noticeable improvement over Japan's SGM series models(100×100),but for the 15 km×100 km lunar orbit,a higher degree-order model can significantly improve the orbit accuracy. | Li PeiJia Hu XiaoGong Huang Yong Wang GuangLi Jiang DongRong Zhang XiuZhong Cao JianFeng Xin Nan | 2012 | Science China(Physics,Mechanics & Astronomy)2012,55,3: | 30 |
| 2 | Orbit determination of Chang'E-3 and positioning of the lander and the rover显示文摘Chang’E-3 landed on the east of Sinus Iridum area on December 14,2013,performing China’s first successful soft landing on the lunar surface.We present the results on precision orbit determination and positioning of the lander and the rover.We describe the data,modeling,and methods used to achieve position knowledge over the period December 2–21,2014.In addition to the radiometric X-band range and Doppler tracking data,delta differential one-way ranging data are also used in the calculation,which show that they strongly improve the accuracy of the orbit reconstruction.Total position overlap differences are about 20 and 30 m for the 100 km 9 100 km and100 km9 15 km lunar orbit,respectively,increased by*50%with respect to CE-2 and at the same level as other lunar spacecrafts of recent era such as SELENE and lunar reconnaissance orbiter(LRO).The position error of the soft landing trajectory is less than 100 m.A kinematic statistical method is applied to determine the position of the lander and relative position of the rover with respect to the lander.The position difference of the lander is better than50 m compared to LRO photograph result.Compared with the delta very long baseline interferometry(VLBI)group delay between the lander and the rover,the delta VLBI phase delay can improve the relative position of the rover from*1,000 to*1 m. | Yong Huang Shengqi Chang Peijia Li Xiaogong Hu Guangli Wang Qinghui Liu Weimin Zheng Min Fan | 2014 | Chinese Science Bulletin2014,59,29: | 28 |
| 3 | Precise positioning of the Chang'E-3 lunar lander using a kinematic statistical method显示文摘A kinematic statistical method is proposed to determine the position for Chang'E-3(CE-3) lunar lander.This method uses both ranging and VLBI measurements to the lander for a continuous arc,combing with precise knowledge about the motion of the moon as provided by planetary ephemeris,to estimate the lander's position on the lunar surface with high accuracy.Accuracy analyses are carried out with simulation data using the software developed at Shanghai Astronomical Observatory in this study to show that measurement errors will dominate the position accuracy.Application of lunar digital elevation model(DEM) as constraints in the lander positioning is also analyzed.Simulations show that combing range/doppler and VLBI data,single epoch positioning accuracy is at several hundred meters level,but with ten minutes data accumulation positioning accuracy is able to be achieved with several meters.Analysis also shows that the information given by DEM can provide constraints in positioning,when DEM data reduce a 3-dimensional positioning problem to 2-dimensional.Considering the Sinus Iridum,CE-3 lander's planned landing area,has been observed with dedicated details during the CE-1 and CE-2 missions,and its regional DEM model accuracy may be higher than global models,which will certainly support CE-3's lander positioning. | HUANG Yong HU XiaoGong LI PeiJia CAO JianFeng JIANG DongRong ZHENG WeiMin FAN Min | 2012 | Chinese Science Bulletin2012,57,35: | 11 |
| 4 | SNR periodical variation of Chang'E-3 spacecraft orbiting the Moon显示文摘Chang'E-3 spacecraft was orbiting the Moon from December 6–14, 2013, and very long baseline interferometry(VLBI) observations were performed to improve the accuracy of its orbit determination. In the process of recording VLBI raw data, 2 bits quantization was implemented.Interesting phenomenon was that signal-to-noise ratio(SNR) of each VLBI station experienced periodical change and had large variation on amplitude while in the Moon's orbit, whereas SNR kept in a stable level after Chang'E-3 landed on the Moon. Influence of varying elevation angle on SNR was analyzed and compensation of 2 bits quantization harmonics to SNR calculation was investigated. Most importantly, telescope system noise temperature increase caused by the Moon was computed along the time of Chang'E-3 orbiting the Moon, and well matched SNR changing trend in terms of correlation coefficients. | he qingbao liu qinghui li peijia kawaguchi noriyuki wu yajun zheng xin zhang juan xu zhijun | 2016 | Chinese Journal of Aeronautics2016,29,2: | 2 |
| 5 | Qualitative and quantitative analysis of Arnebiae Radix and Dictamni Cortex and efficacy study of herbal extracts on allergic contact dermatitis using 3D human reconstructed epidermis显示文摘Objective:To evaluate the quality of Arnebiae Radix(AR)and Dictamni Cortex(DC)and study the efficacy of herbal extracts of these two herbs on the treatment of allergic contact dermatitis(ACD).Methods:Qualitative and quantitative analysis of effective components was performed using High Performance Thin Layer Chromatography(HPTLC),High Performance Liquid Chromatography(HPLC),and HPLC-Quadrupole Time of Flight-Mass Spectrometry(HPLC-QTOF-MS).In vitro allergic ACD 3D model was established by incubating 3D reconstructed human epidermis(RHE)with skin sensitizer,potassium dichromate.A total of 65 gene expression that were associated with ACD,which included 24 antioxidant responsive element(ARE)and 41 SENS-IS genes were quantified by q RT-PCR.More than or equal to 10 ARE genes and 18 SENN-IS genes were induced by 1.3-fold,demonstrating the successful establishment of in vitro ACD model.Oil extracts of AR and DC were applied on the in vitro ACD model to study the efficacy.Results:Batch 3 of AR and batch 2 of DC showed presence of all active ingredients with the highest concentrations.Active ingredients of the herbs were extracted using a special oil and formulated into herbal oil extracts.The herbal oil extracts were able to down regulate the induced genes in the in-vitro ACD skin model,bringing the tissue back to homeostatic status.Conclusion:The oil extracts showed the potent efficacy of using AR and DC in ACD treatment.The combination study will be done to optimize the formulation ratio which will be developed into a topical cream. | Huan Li Esther Lim Gladys Ang Zhi-qing Lim Martin Hui Cai Jo-anne Loh Celine Ng Peijia Seetoh Edmund Tian Lay Beng Goh | 2021 | Chinese Herbal Medicines2021,13,4: | 0 |