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Ergodic sum rate for uplink NOMA transmission in satellite-aerial-ground integrated networks

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Chinese Journal of Aeronautics 2022年第9期35卷 58-70页

作者： Huaicong KONG Min LIN Jian ZHANG Jian OUYANG jun-bo wang Prabhat K.UPADHYAY College of Telecommunications and Information Engineering Nanjing University of Posts and TelecommunicationsNanjing 210003China National Mobile Communications Research Laboratory Southeast UniversityNanjing 210096China Discipline of Electrical Engineering Indian Institute of Technology IndoreIndore 453552India

The application of Non-Orthogonal Multiple Access(NOMA) technology into satelliteaerial-ground integrated networks can meet the requirements of ultra-high rate and massive connectivity for the Sixth-Generation(6G) communication systems. We consider an uplink NOMA scenario for such a satellite-aerial-ground integrated network where multiple users communicate with satellite under the help of an Unmanned Aerial Vehicle(UAV) as an aerial relay equipped with a phased array. Supposing that buffer-aided decode-and-forward protocol is adopted at the UAV relay, we first formulate an optimization problem to maximize Ergodic Sum Rate(ESR) of the considered system subject to individual power constraint and quality-of-service constraint of each ***, with known imperfect channel state information of each user, we propose a joint power allocation and robust Beam Forming(BF) iterative algorithm to maximize ESR for the user-to-UAV link. Besides, to take the advantages of Free-Space Optical(FSO) and millimeter Wave(mmWave)communications, we present a switch-based hybrid FSO/mmWave scheme and a robust BF algorithm for the UAV-to-satellite link to achieve higher rate. Moreover, a closed-form ESR expression is derived. Finally, the effectiveness and correctness of the proposed solutions are verified by numerical simulations, and the performance evaluation results show that the proposed solutions not only achieve performance enhancement and robustness, but also outperform the orthogonal multiple access significantly.

关键词： BeamForming(BF) Ergodic Sum Rate(ESR) Hybrid FSO/mmWave Non-Orthogonal Multiple Access(NOMA) Satellite-aerial-ground integrated network The Sixth-Generation(6G)communication system

Exact Location of Linear B-cell Epitopes of VP3 Protein of Goose Parvovirus

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畜牧兽医学报 2011年第B12期42卷 34-39页

作者： GUO Lu JU Huan-yu YU Tian-fei JING Zhi-qiang MA bo wang jun-wei （College of Veterinary Medicine Northeast Agricultural University Harbin 150030 China）

Four monoclonal antibodies (MAbs) against Goose Parvovirus (GPV) VP3 protein already available were used to precisely locate linear B-cell epitopes in VP3 of GPV. The epitopes, recognized by four MAbs, had already been identified at low levels of resolution. Complementary oligonucleotides encoding ten amino acid fragments, with five amino acid overlaps were designed with suitable sticky ends for recombination with pET-32a and subsequent expression as small-fragment fusion proteins. Antigenicity of specific oligopeptides was determined by Western blotting with the MAbs. Using the same methods, amino acids were deleted one by one from the peptides of interest, enabling the two epitopes to be precisely located at amino acids 430-435 (-DRIMNP-) and 643-647 (-VFIKN-).

关键词： VP3基因鹅细小病毒 B细胞表位 VP3蛋白抗原表位线性单克隆抗体位置

The FAST Galactic Plane Pulsar Snapshot survey:*** design and pulsar discoveries

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Research in Astronomy and Astrophysics 2021年第5期21卷 5-42页

作者： J.L.Han Chen wang P.F.wang Tao wang D.J.Zhou Jing-Hai Sun Yi Yan Wei-Qi Su Wei-Cong Jing Xue Chen X.Y.Gao Li-Gang Hou jun Xu K.J.Lee Na wang Peng Jiang Ren-Xin Xu jun Yan Heng-Qian Gan Xin Guan Wen-jun Huang Jin-Chen Jiang Hui Li Yun-Peng Men Chun Sun bo-jun wang H.G.wang Shuang-Qiang wang Jin-Tao Xie Heng Xu Rui Yao Xiao-Peng You D.J.Yu Jian-Ping Yuan Rai Yuen Chun-Feng Zhang Yan Zhu National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China CAS Key Laboratory of FAST NAOCChinese Academy of SciencesBeijing 100101China School of Astronomy University of Chinese Academy of SciencesBeijing 100049China Kavli Institute for Astronomy and Astrophysics Peking UniversityBeijing 100871China Department of Astronomy Peking UniversityBeijing 100871China Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China Key Laboratory of Radio Astronomy Chinese Academy of SciencesNanjing 210008China Department of Astronomy Guangzhou UniversityGuangzhou 510006China School of Physical Science and Technology Southwest UniversityChongqing 400715China

Discovery of pulsars is one of the main goals for large radio *** Five-hundredmeter Aperture Spherical radio Telescope(FAST),that incorporates an L-band 19-beam receiver with a system temperature of about 20 K,is the most sensitive radio telescope utilized for discovering *** designed the snapshot observation mode for a FAST key science project,the Galactic Plane Pulsar Snapshot(GPPS)survey,in which every four nearby pointings can observe a cover of a sky patch of 0.1575 square degrees through beam-switching of the L-band 19-beam *** integration time for each pointing is 300 seconds so that the GPPS observations for a cover can be made in 21 *** goal of the GPPS survey is to discover pulsars within the Galactic latitude of±10∘from the Galactic plane,and the highest priority is given to the inner Galaxy within±5∘.Up to now,the GPPS survey has discovered 201 pulsars,including currently the faintest pulsars which cannot be detected by other telescopes,pulsars with extremely high dispersion measures(DMs)which challenge the currently widely used models for the Galactic electron density distribution,pulsars coincident with supernova remnants,40 millisecond pulsars,16 binary pulsars,some nulling and mode-changing pulsars and rotating radio transients(RRATs).The follow-up observations for confirmation of new pulsars have polarization-signals recorded for polarization profiles of the ***-detection of previously known pulsars in the survey data also leads to significant improvements in parameters for 64 *** GPPS survey discoveries are published and will be updated at http://***/GPPS/.

关键词： pulsars:general

FAST Observations of an Extremely Active Episode of FRB 20201124A.Ⅱ.Energy Distribution

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Research in Astronomy and Astrophysics 2022年第12期22卷 70-80页

作者： Yong-Kun Zhang Pei wang Yi Feng Bing Zhang Di Li Chao-Wei Tsai Chen-Hui Niu Rui Luo Ju-Mei Yao Wei-Wei Zhu Jin-Lin Han Ke-Jia Lee De-Jiang Zhou Jia-Rui Niu Jin-Chen Jiang Wei-Yang wang Chun-Feng Zhang Heng Xu bo-jun wang Jiang-Wei Xu National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Research Center for Intelligent Computing Platforms Zhejiang LaboratoryHangzhou 311100China Department of Physics and Astronomy University of NevadaLas VegasNV 89154USA Nevada Center for Astrophysics University of NevadaLas VegasNV 89154USA NAOC-UKZN Computational Astrophysics Centre University of KwaZulu-NatalDurban 4000South Africa CSIRO Space and Astronomy PO Box 76EppingNSW 1710Australia Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China Kavli Institute for Astronomy and Astrophysics Peking UniversityBeijing 100871China Department of Astronomy Peking UniversityBeijing 100871China

We report the properties of more than 800 bursts detected from the repeating fast radio burst(FRB)source FRB20201124A with the Five-hundred-meter Aperture Spherical radio Telescope(FAST)during an extremely active episode on UTC 2021 September 25–28 in a series of four *** this second paper of the series,we study the energy distribution of 881 bursts(defined as significant signals separated by dips down to the noise level)detected in the first four days of our 19 hr observational campaign spanning 17 *** event rate initially increased exponentially but the source activity stopped within 24 hr after the 4th *** detection of 542 bursts in one hour during the fourth day marked the highest event rate detected from one single FRB source so *** bursts have complex structures in the time-frequency *** find a double-peak distribution of the waiting time,which can be modeled with two log-normal functions peaking at 51.22 ms and 10.05 s,*** with the emission from a previous active episode of the source detected with FAST,the second distribution peak time is smaller,suggesting that this peak is defined by the activity level of the *** calculate the isotropic energy of the bursts using both a partial bandwidth and a full bandwidth and find that the energy distribution is not significantly *** find that an exponentially connected broken-power law function can fit the cumulative burst energy distribution well,with the lower and higher-energy indices being-1.22±0.01 and-4.27±0.23,*** a radio radiative efficiency ofη_(r)=10^(-4),the total isotropic energy of the bursts released during the four days when the source was active is already 3.9×10^(46)erg,exceeding~23%of the available magnetar dipolar magnetic *** challenges the magnetar models which invoke an inefficient radio emission(e.g.,synchrotron maser models).

关键词： (stars:)pulsars:general stars:individual(FRB 20201124A) methods:data analysis

Scintillation Arc from FRB 20220912A

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Science China(Physics,Mechanics & Astronomy) 2024年第1期67卷 134-142页

作者： Zi-Wei Wu Robert AMain Wei-Wei Zhu Bing Zhang Peng Jiang Jia-Rui Niu Jin-Lin Han Di Li Ke-Jia Lee Dong-Zi Li Yuan-Pei Yang Fa-Yin wang Rui Luo Pei wang Chen-Hui Niu Heng Xu bo-jun wang Wei-Yang wang Yong-Kun Zhang Yi Feng De-Jiang Zhou Yong-Hua Xu Can-Min Deng Yu-Hao Zhu National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China Max-Planck-Institut für Radioastronomie Bonn 53121Germany Institute for Frontier in Astronomy and Astrophysics Beijing Normal UniversityBeijing 102206China Nevada Center for Astrophysics and Department of Physics and Astronomy University of NevadaLas VegasNV 89154USA CAS Key Laboratory of FAST National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China School of Astronomy University of Chinese Academy of SciencesBeijing 100049China NAOC-UKZN Computational Astrophysics Centre University of KwaZulu-NatalDurban 4000South Africa Department of Astronomy Peking UniversityBeijing 100871China Kavli Institute for Astronomy and Astrophysics Peking UniversityBeijing 100871China Cahill Center for Astronomy and Astrophysics California Institute of TechnologyPasadena 91125USA South-Western Institute For Astronomy Research Yunnan UniversityKunming 650504China School of Astronomy and Space Science Nanjing UniversityNanjing 210093China Key Laboratory of Modern Astronomy and Astrophysics(Nanjing University) Ministry of EducationNanjing 210023China CSIRO Space and Astronomy Epping 1710Australia Department of Astronomy School of Physics and Materials ScienceGuangzhou UniversityGuangzhou 510006China Research Center for Intelligent Computing Platforms Zhejiang LaboratoryHangzhou 311100China Yunnan Observatories Chinese Academy of SciencesKunming 650011China Guangxi Key Laboratory for Relativistic Astrophysics Department of PhysicsGuangxi UniversityNanning 530004China

We present the interstellar scintillation analysis of fast radio burst(FRB)20220912A during its extremely active episode in 2022using data from the Five-hundred-meter Aperture Spherical Radio Telescope(FAST).We detect a scintillation arc in the FRB’s secondary spectrum,which describes the power in terms of the scattered FRB signals’time delay and Doppler *** arc indicates that the scintillation is caused by a highly localized *** analysis favors a Milky Way origin of the ionized interstellar medium(IISM)for the localized scattering medium but cannot rule out a host galaxy *** present our method for detecting the scintillation arc,which can be applied generally to sources with irregularly spaced bursts or *** methods could help shed light on the complex interstellar environment surrounding the FRBs and in our Galaxy.

关键词： fast radio burst scintillation FRB 20220912A

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The Analysis of the Phenomenon for ECRH Gyrotrons Test

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Southwestern Institute of Physics Annual Report

Southwestern Institute of Physics Annual Report 2005年第1期 49-51页

作者： RAO jun KANG Zihua LI bo ZHOU jun wang Mingwei FENG Kun XUAN Weimin YAO Lieying

in HL-2A tokamak the system of ECRH has been consisted of two gyrotrons that each is 500 kW of the microwave output power, the frequency is 68 ±0.1 GHz and the duration is 1 s. A set of appropriate parameters of the power supply and the control procedure are very important during the test of gyrotrons. Basing on analysis of the phenomenon observed, we conside that the troubles came from mainly the stability of the power supply, the sequence of control, the overcurrent protection and the grounding of the system. The solutions have been put forward and the system have been improved partly. The gyrotron has been adjusted one by one. This paper introduces the analysis of power supply for gyrotrons.

关键词： ECRH Gyrotron Test

FAST Observations of an Extremely Active Episode of FRB 20201124A.Ⅳ.Spin Period Search

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Research in Astronomy and Astrophysics 2022年第12期22卷 99-122页

作者： Jia-Rui Niu Wei-Wei Zhu Bing Zhang Mao Yuan De-Jiang Zhou Yong-Kun Zhang Jin-Chen Jiang J.L.Han Di Li Ke-Jia Lee Pei wang Yi Feng Dong-Zi Li Rui Luo Fa-Yin wang Zi-Gao Dai Chen-Chen Miao Chen-Hui Niu Heng Xu Chun-Feng Zhang Wei-Yang wang bo-jun wang Jiang-Wei Xu National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Institute for Frontier in Astronomy and Astrophysics Beijing Normal UniversityBeijing 102206China Department of Physics and Astronomy University of NevadaLas VegasNV 89154USA Department of Astronomy Peking UniversityBeijing 100871China NAOC-UKZN Computational Astrophysics Centre University of KwaZulu-NatalDurban 4000South Africa Kavli Institute for Astronomy and Astrophysics Peking UniversityBeijing 100871China Research Center for Intelligent Computing Platforms Zhejiang LaboratoryHangzhou 311100China Cahill Center for Astronomy and Astrophysics MC 249-17 California Institute of TechnologyPasadena CA 91125USA CSIRO Space and Astronomy PO Box 76EppingNSW 1710Australia School of Astronomy and Space Science Nanjing UniversityNanjing 210093China Key Laboratory of Modern Astronomy and Astrophysics Nanjing UniversityMinistry of EducationNanjing 210093China Department of Astronomy University of Science and Technology of ChinaHefei 230026China

We report the properties of more than 800 bursts detected from the repeating fast radio burst(FRB)source FRB 20201124A with the Five-hundred-meter Aperture Spherical radio Telescope during an extremely active episode on UTC 2021 September 25th-28th in a series of four *** this fourth paper of the series,we present a systematic search of the spin period and linear acceleration of the source object from both 996 individual pulse peaks and the dedispersed time *** credible spin period was found from this data *** rule out the presence of significant periodicity in the range between 1 ms and 100 s with a pulse duty cycleboxcar function)and linear acceleration up to 300 m s^(-2)in each of the four one-hour observing sessions,and up to 0.6 m s^(-2)in all 4 *** searches contest theoretical scenarios involving a 1 ms–100 s isolated magnetar/pulsar with surface magnetic field10 *** also perform a periodicity search of the fine structures and identify 53 unrelated millisecond-timescale“periods”in multicomponents with the highest significance of 3.9σ.The“periods”recovered from the fine structures are neither consistent nor harmonically *** they are not likely to come from a spin *** caution against claiming spin periodicity with significance below~4σwith multi-components from one-off *** discuss the implications of our results and the possible connections between FRB multi-components and pulsar microstructures.

关键词： pulsars:general methods:observational radio continuum:general

Relation between Starlight and Nebular Emission Lines of Star-Forming Galaxies

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Research in Astronomy and Astrophysics 2005年第3期5卷 221-228页

作者： Hong-Lin Lu, Hong-Yan Zhou, Ting-Gui wang, Zhen-Quan Zhuang, Xiao-bo Dong, jun-Xian wang and Cheng Li Department for Electronics of Science & technology, University of Science and Technology of China, Hefei 230026 Center for Astrophysics, University of Science and Technology of China, Hefei 230026 Center for Astrophysics University of Science and Technology of China Hefei 230026

We present an exercise that intends to establish a relationship between the strength of nebular emission lines and optical stellar features in the spectrum of a galaxy. After accurately subtracting the stellar continuum and the underlying stellar absorption, we made reliable measurements of the emission lines of all the galaxies in the Sloan Digital Sky Survey Data Release 2 (SDSS DR2). More than 4000 star-forming galaxies with high S/N ratio of both the stellar spectrum and the emission lines are selected. These galaxy spectra are fitted with the 10 PCs of Yip et al., after all the emission line regions have been filtered out. We find that the flux of hydrogen Balmer emission lines, Ha and Hβcan be well recovered from the PCs, while the metal lines are not well reproduced. The fluxes of Ha and Hβmeasured from the PC-reconstructed spectra and from the observed spectra agree well with an rms scatter of only - 0.1 dex. This result suggests that, with moderate spectral resolution and S/N ratio, the optica

关键词： galaxies: fundamental parameters - galaxies: starburst - radiation: lines continuum

Cooperative Interaction Between the Basic-helix-loop-helix Transcription Factor dHAND and Myocyte Enhancer Factor-2C Regulates Myocardial Gene Expression

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Cooperative Interaction Between the Basic-helix-loop-helix T...