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Position and attitude determination by integrated GPS/SINS/TS for feed support system of FAST

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Research in Astronomy and Astrophysics 2020年第9期20卷 192-200页

作者： Ming-Hui Li Peng Jiang dong jun yul Jing Hai Sun National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

This paper presents a new measurement system based on integration method that can provide all-weather dependability and higher precision for the measurement of FAST's feed support *** measurement system consists of three types of measuring equipments,and a processing software with the core data fusion *** Strapdown Inertial Navigation System(SINS)can autonomously measure the position,speed and attitude of the *** own shortcoming is that the measurement data diverge rapidly over *** must combine the Global Positioning System(GPS)and the Total Station(TS)to obtain high-precision measurement *** Kalman filtering algorithm is adopted for the integration measurement system,which is an optimal algorithm to estimate the measurement errors.A series of tests are carried out to evaluate the *** the feed cabin,the maximum RMS of the position is 14.56 mm,the maximum RMS of the attitude is 0.095,these values are less than 15 mm and 0.1°as the precision for measuring the feed *** the Stewart manipulator,the maximum RMS of the position is 2.99 mm,the maximum RMS of the attitude is 0.093°,these values are less than 3 mm and 0.1°as the precision for measuring the Stewart *** a result,the new measurement meets the requirement of measurement precision for FAST's feed support system.

关键词： FAST Integration measurement system GPS/SINS/TS Kalman Filter

Simulation of FAST EM performance for both the axial and lateral feed defocusing

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Research in Astronomy and Astrophysics 2020年第5期20卷 127-131页

作者： Heng-Qian Gan Peng Jiang Kai Zhu Jing-Hai Sun Rui Yao dong-jun yu National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China

Five-hundred-meter Aperture Spherical radio Telescope(FAST)is the world’s largest single dish radio telescope,which is located in Guizhou Province,in southwest *** FAST feed cabin is supported and positioned by six steel *** deviation of the feed position and orientation would lead to loss in the telescope *** this paper,a series of electromagnetic(EM)simulations of the FAST facility with varying feed positions and orientation offsets was *** maximum gain of FAST is about 82.3 dBi and the sibelobe is–32 dB with respect to the main beam at 3 *** simulation results have demonstrated that the telescope efficiency loss is more sensitive to the lateral feed deviation compared with the axial *** telescope efficiency would decrease by 8.2%due to the FAST feed position deviation of 10 mm rms when the observing frequency is 3 *** FAST feed deviation basically has no effect on the sidelobes and cross polarization characteristic according to the simulations.

关键词： techniques:FAST Telescope telescope efficiency feed position error

A motion planning algorithm for the feed support system of FAST

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Research in Astronomy and Astrophysics 2020年第5期20卷 117-126页

作者： Rui Yao Peng Jiang Jing-Hai Sun dong-jun yu Chun Sun National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China CAS Key Laboratory of FAST National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China

The paper relates to a motion planning algorithm for the feed support system of the Five-hundred-meter Aperture Spherical radio Telescope(FAST).To enhance the stability of the feed support system,the start/termination planning segments are adopted with an acceleration and deceleration *** source switching planning adopts a combination of a line segment and focal segment to realize stable control of the feed support ***,during the observation trajectory,a transition segment which is not used for observation data is planned with a required *** an example simulation,a smooth change is realized via the motion planning algorithm and presented in this paper.

关键词： FAST radio telescope motion planning

TripletGO: Integrating Transcript Expression Profiles with Protein Homology Inferences for Gene Function Prediction

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Genomics, Proteomics & Bioinformatics 2022年第5期20卷 1013-1027页

作者： Yi-Heng Zhu Chengxin Zhang Yan Liu Gilbert S.Omenn Peter L.Freddolino dong-jun yu Yang Zhang School of Computer Science and Engineering Nanjing University of Science and TechnologyNanjing 210094China Department of Computational Medicine and Bioinformatics University of MichiganAnn ArborMI 48109USA Departments of Internal Medicine and Human Genetics and School of Public HealthUniversity of MichiganAnn ArborMI 48109USA Department of Biological Chemistry University of MichiganAnn ArborMI 48109USA

Gene Ontology(GO)has been widely used to annotate functions of genes and gene ***,we proposed a new method,Triplet GO,to deduce GO terms of protein-coding and noncoding genes,through the integration of four complementary pipelines built on transcript expression profile,genetic sequence alignment,protein sequence alignment,and naīve *** GO was tested on a large set of 5754 genes from 8 species(human,mouse,Arabidopsis,rat,fly,budding yeast,fission yeast,and nematoda)and 2433 proteins with available expression data from the third Critical Assessment of Protein Function Annotation challenge(CAFA3).Experimental results show that Triplet GO achieves function annotation accuracy significantly beyond the current state-of-the-art *** analyses show that the major advantage of Triplet GO lies in the coupling of a new triplet network-based profiling method with the feature space mapping technique,which can accurately recognize function patterns from transcript expression ***,the combination of multiple complementary models,especially those from transcript expression and protein-level alignments,improves the coverage and accuracy of the final GO annotation *** standalone package and an online server of Triplet GO are freely available at https://***/Triplet GO/.

关键词： Gene function annotation Gene Ontology Transcript expression profile Triplet network Protein-level alignment

The fundamental performance of FAST with 19-beam receiver at L band

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Research in Astronomy and Astrophysics 2020年第5期20卷 65-92页

作者： Peng Jiang Ning-yu Tang Li-Gang Hou Meng-Ting Liu Marko Krco Lei Qian Jing-Hai Sun Tao-Chung Ching Bin Liu Yan Duan You-Ling yue Heng-Qian Gan Rui Yao Hui Li Gao-Feng Pan dong-jun yu Hong-Fei Liu Di Li Bo Peng jun Yan FAST Collaboration National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China CAS Key Laboratory of FAST National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100101China

The Five-hundred-meter Aperture Spherical radio Telescope(FAST) has passed national acceptance and finished one pilot cycle of ‘Shared-Risk’ observations. It will start formal operation soon. In this context, this paper describes testing results of key fundamental parameters for FAST, aiming to provide basic support for observation and data reduction of FAST for scientific researchers. The 19-beam receiver covering 1.05–1.45 GHz was utilized for most of these observations. The fluctuation in electronic gain of the system is better than 1% over 3.5 hours, enabling enough stability for observations. Pointing accuracy,aperture efficiency and system temperature are three key parameters for FAST. The measured standard deviation of pointing accuracy is 7.9′′, which satisfies the initial design of FAST. When zenith angle is less than 26.4°, the aperture efficiency and system temperature around 1.4 GHz are ~0.63 and less than 24 K for central beam, respectively. The sensitivity and stability of the 19-beam backend are confirmed to satisfy expectation by spectral HI observations toward NGC 672 and polarization observations toward 3 C 286. The performance allows FAST to take sensitive observations for various scientific goals, from studies of pulsars to galaxy evolution.

关键词： instrumentation:detectors line:profiles

小梁切除巩膜层间隧道房水引流术与MMC治疗难治性青光眼分析

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中国实用眼科杂志 2010年第3期28卷 292-295页

作者：董玉君辽宁朝阳市中心医院眼科 122000

目的探讨小梁切除巩膜层间隧道房水引流术与MMC治疗难治性青光眼的临床效果。方法采用随机对照的方法，将103例108只眼难治性青光眼随机分为两组，隧道组51例53只眼，采用小梁切除巩膜层间隧道房水引流加MMC进行手术治疗；小梁组52例55... 详细信息

目的探讨小梁切除巩膜层间隧道房水引流术与MMC治疗难治性青光眼的临床效果。方法采用随机对照的方法，将103例108只眼难治性青光眼随机分为两组，隧道组51例53只眼，采用小梁切除巩膜层间隧道房水引流加MMC进行手术治疗；小梁组52例55只眼，采用传统的小梁切除术加MMC。观察术后视力、眼压、滤过泡、手术成功率、并发症等情况。术后随访1-24个月。结果两组术后1个月视力比较无统计学意义（P〉0．05），术后12个月时光感至0．1、0．7至1．0有统计学意义（P〈0．05）。两组各时段眼压比较差异有统计学意义（P〈0.05）。功能性滤过泡分布情况各时期均有统计学意义（P〈0．05）。手术成功率12个月、24个月时两种比较均有统计学意义（P〈0．05）。结论小梁切除巩膜层间隧道房水引流术加MMC治疗难治性青光眼，术式简单易行，效果稳定可靠，手术成功率高，是治疗难治性青光眼较为理想的术式。

关键词：小梁切除巩膜层间隧道 MMC 难治性青光眼

Pilot HI survey of Planck Galactic Cold Clumps with FAST

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Research in Astronomy and Astrophysics 2020年第5期20卷 181-192页

作者： Ning-yu Tang Pei Zuo Di Li Lei Qian Tie Liu yue-Fang Wu Marko Krco Meng-Ting Liu You-Ling yue Yan Zhu Hong-Fei Liu dong-jun yu Jing-Hai Sun Peng Jiang Gao-Feng Pan Hui Li Heng-Qian Gan Rui Yao Shu Liu FAST Collaboration National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China CAS Key Laboratory of FAST National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China Kavli Institute for Astronomy and Astrophysics Peking UniversityBeijing 100871China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China Shanghai Astronomical Observatory Chinese Academy of SciencesShanghai 200030ChinaShanghai 200030China East Asian Observatory HI 96720USA Department of Astronomy School of PhysicsPeking UniversityBeijing 100871China

We present a pilot HI survey of 17 Planck Galactic Cold Clumps(PGCCs)with the Five-hundred-meter Aperture Spherical radio Telescope(FAST).HI Narrow Self-Absorption(HINSA)is an effective method to detect cold HI being mixed with molecular hydrogen H2 and improves our understanding of the atomic to molecular transition in the interstellar *** was found in 58%PGCCs that we *** column density of HINSA was found to have an intermediate correlation with that of 13CO,following log(N(HINSA))=(0.52±0.26)log(N13CO)+(10±4.1).HI abundance relative to total hydrogen[HI]/[H]has an average value of 4.4×10-3,which is about 2.8 times of the average value of previous HINSA surveys toward molecular *** clouds with total column density NH>5×1020 cm-2,an inverse correlation between HINSA abundance and total hydrogen column density is found,confirming the depletion of cold HI gas during molecular gas formation in more massive *** line width of 13CO is about 0-0.5 kms-1 larger than that of *** possible explanation of narrower non-thermal width of HINSA is that HINSA region is smaller than that of *** on an analytic model of H2 formation and H2 dissociation by cosmic ray,we found the cloud ages to be within 106.7-107.0 yr for five sources.

关键词： ISM:clouds ISM:evolution ISM:molecules

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控股股东利益最大化与上市公司股利分配政策

科学．经济．社会 2006年第2期24卷 41-45页

作者：王宗军董育军华中科技大学管理学院武汉430074

在分析我国上市公司股权流通性割裂现状的基础上,得出上市公司的控股股东以每股净资产最大化和对上市公司经济资源的控制或索取为其主要目标这一结论,然后从我国上市公司的股利实践(分为不分配现金股利,为再融资而满足监管条件的低派现... 详细信息

在分析我国上市公司股权流通性割裂现状的基础上,得出上市公司的控股股东以每股净资产最大化和对上市公司经济资源的控制或索取为其主要目标这一结论,然后从我国上市公司的股利实践(分为不分配现金股利,为再融资而满足监管条件的低派现,和控股股东的高派现套现这三种),证明了上市公司的股利政策是控股股东从自己的利益最大化为出发点而制定的,是为控股股东的利益服务的。

关键词：现金股利控股股东上市公司股利政策

Study on effect of feed ratio on controlled cross-linking polymerization process

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Journal of Chemistry and Chemical Engineering 2007年第1期1卷 27-39页

作者： LI Fang-xing YANG Jin-dong SUN Rui-min REN Jin-yun ZHONG Lu-wei LIU dong-ping CHEN jun yu Fang-fei Department of Chemistry Nankai University Tianjin 300071 China

A controlled cross-linking polymerization containing intra- and intermolecular reactions was designed based on random coil morphology of macromolecules in solution. The soluble intramolecular cross-linked maeromolecule （ICM） was successfully synthesized in the system with PVA and MDI. We found an especial dissolving phenomenon, namely the semi-soluble phenomenon when some gels dissolved in DMF. The chain growth process of ICMs was investigated by Transmission electron microscopy （TEM） pictures of samples at different reacting times, in addition, TEM pictures show ICMs have three kinds of styles in structure, viz. ＂globule structure＂, ＂nubby structure＂ and the intervenient between the above two structures, and the efflux time of the ICMs was measured by an Ubbelohde viscosimeter, it was found that the efflux time decreases with the degree ofcrosslink increasing.

关键词： intramolecularly cross-linked macromolecule cross-linking solution behavior dynamic light scattering