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china Communications 2024年第3期21卷 260-272页

作者： Zhang Mengjiao Liu yu Huang Jie He Ruisi Zhang Jingfan yu Chongyang wang Chengxiang School of Microelectronics Shandong UniversityJinan 250101China The State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong UniversityBeijing 100044China The National Mobile Communications Research Laboratory School of Information Science and EngineeringSoutheast UniversityNanjing 210096China The purple mountain Laboratories Nanjing 211111China

A large amount of mobile data from growing high-speed train(HST)users makes intelligent HST communications enter the era of big *** corresponding artificial intelligence(AI)based HST channel modeling becomes a *** paper provides AI based channel characteristic prediction and scenario classification model for millimeter wave(mmWave)HST ***,the ray tracing method verified by measurement data is applied to reconstruct four representative HST *** setting the positions of transmitter(Tx),receiver(Rx),and other parameters,the multi-scenarios wireless channel big data is ***,based on the obtained channel database,radial basis function neural network(RBF-NN)and back propagation neural network(BP-NN)are trained for channel characteristic prediction and scenario ***,the channel characteristic prediction and scenario classification capabilities of the network are evaluated by calculating the root mean square error(RMSE).The results show that RBF-NN can generally achieve better performance than BP-NN,and is more applicable to prediction of HST scenarios.

关键词： artificial intelligence channel characteristic prediction HST channel millimeter wave scenario classification

A Note on the Mixing Length Theory and Massive Star Evolution

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Chinese Journal of Astronomy and Astrophysics 2001年第1期1卷 50-56页

作者： Li-Cai deng and Da-Run Xiong ( Beijing Astronomical observatory, Chinese Academy of Sciences, Beijing 100012 purple mountain observatory, Chinese Academy of Sciences, nanjing210008 National Astronomical Observatories, Chinese Academy of Sciences, Beij Beijing Astronomical observatory Chinese Academy of Sciences Beijing 100012 National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 CAS-Peking University Joint Beijing Astrophysical Center Beijing 100871 purple mountain observatory Chinese Academy of Sciences Nanjing 210008

In this paper, we investigate the problem of supersonic convection caused by the application of the usual Mixing Length Theory (MLT), and give a modification to the original expression of the MLT. In the case of the usual MLT, a zone of supersonic convection exists when the stellar model goes into yellow-red supergiant phase. When the modification is applied, the models of late type supergiants possess shallower convective envelopes for a given temperature compared with the normal formalism of the MLT. Therefore the stellar models made with our new formalism move to lower effective temperature by 100-400 K depending on the luminosity of the star. Such a modification does not affect the convective envelope structure of lower luminosity late type stars, as both expressions of the MLT give the same result. In these stars.

关键词： convection - stars: supergiants - stars: massive stars - stars: evolution

Drifting bands of solar radio spikes

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Chinese Science Bulletin 2008年第4期53卷 638-640页

作者： XU FuYing1,2& WU HongAo1,2 1 purple mountain observatory,Chinese Academy of Sciences,nanjing 210008,china 2 National Astronomical Observatories,Chinese Academy of Sciences,Beijing 100012,china purple mountain observatory Chinese Academy of Sciences Nanjing China National Astronomical Observatories Chinese Academy of Sciences Beijing China

The solar flare(1N/C5.3) occurred in NOAA 8742 on October 27,1999,and the accompanied complex radio burst was observed by the spectrometer with both high temporal(5 ms) and frequency(10 MHz) resolutions at purple mountain observatory(PMO).It started at 04:27:42 UT,peaked at 04:28:42 UT and ended at 04:29:18 *** most significant feature of the event might be the sequential spikes in both time and frequency to form three slow drift bands over the frequency range of ～5 to ≥7.5 GHz with almost the same drift rate about 2.7 GHz/*** relative bandwidth for the individual spikes varied from 1.6% to 4.9%,typically 3.3%.Based on electron cyclotron maser action driven by loss-cone anisotropy,the rare phenomena of slow drift band consisting of spikes were interpreted by spike source moving back and forth along the magnetic ***,the estimations of the narrow bandwidths of spike given by electron cyclotron maser theory coincided well with the observations.

关键词：太阳耀斑微波爆裂太阳活动天文学

Simulations for terrestrial planets formation

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Science china(Physics,Mechanics & Astronomy) 2009年第5期52卷 794-803页

作者： ZHANG Niu 1,2 &JI JiangHui 2,3 1Graduate University of Chinese Academy of Sciences,Beijing 100049,china 2purple mountain observatory,Chinese Academy of Sciences,nanjing 210008,china 3 National Astronomical Observatories,Chinese Academy of Sciences,Beijing 100012,china Graduate University of Chinese Academy of Sciences Beijing China purple mountain observatory Chinese Academy of Sciences Nanjing China National Astronomical Observatories Chinese Academy of Sciences Beijing China

In this paper,the formation of terrestrial planets in the late stage of planetary formation is investigated using the two-planet *** that time,the protostar formed for about 3 Ma and the gas disk *** the model,the perturbations from Jupiter and Saturn are *** of the mass of outer planet,and the initial eccentricities and inclinations of embryos and planetesimals are also *** results show that,terrestrial planets are formed in 50 Ma,and the accretion rate is about 60%-80%.In each simulation,3-4 terrestrial planets are formed inside"Jupiter"with masses of 0.15 -3.6M⊕.In the 0.5-4 AU,when the eccentricities of planetesimals are excited,planetesimals are able to accrete material from wide radial *** plenty of water material of the terrestrial planet in the Habitable Zone may be transferred from the farther places by this *** could also happen a few times between two major planets only if the outer planet has a moderate mass and the small terrestrial planet could survive at some resonances over time scale of 10 8 *** one of our simulations,commensurability of the orbital periods of planets is very ***,a librating-circulating 3:2 configuration of mean motion resonance is found.

关键词： astrophysics exoplanet planetary formation n-body simulation

RAMAN SPECTRA OF SEVEN INTERPLANETARY DUST PARTICLES

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空间科学学报 1992年第1期 57-62页

作者： Xu Yin-lin yu Min(purple mountain observatory, nanjing)Chang-yun Fan(University of Arizona, USA)

The Raman Shift Spectra of seven interplanetary dust particles,U2034 (F10),U2034(F8),U2022(B1),W7074 18,W7074 C15,W7074 C3 and W7074 A7,were measured with a Spex-1403 Raman *** exciting radiations were the 488 nm and 514 nm line of a 5W argon ion *** seven spectra exhibit the 1350 and 1600 Acm-1 arbon bands,implying that the IDPS were coated with hydrocarbon and incompletely crystallized carbon,the part of which may be the residue of hydro-carbon contents in the particles after water loss by the heating during their entry into the earth’s atmosphere.A weak band structure in the 520-610 cm-1 range could be caused by cyclosilicates,and a weak band at 2900 cm-1 is tentatively identified as due to hydrocarbon molicules.

关键词： Interplanetary Dust Particles Raman Spectra Carbon

Discrepancy between infrared and optical emission in some Be stars

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Chinese Science Bulletin 2002年第18期47卷 1511-1513页

作者： LIU Qingzhong & WEI Jianyanpurple mountain observatory, Chinese Academy of Sciences, nanjing210008, china National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012, china purple mountain observatory Chinese Academy of Sciences Nanjing China National Astronomical Observatories Chinese Academy of Sciences Beijing China

An expanding ring model is put forward to investigate the original regions of Ha line emission and infrared excess emission in Be stars, by taking optical depth into account. We find that the two regions depend strongly on the physical properties of the envelope of Be stars such as the initial density and density structure. This model can be used to qualitatively interpret the disagreement between the near infrared excess and the equivalent width (EW) of Ha emission line, as observed in some Be stars.

关键词： Be star emission line near infrared excess.

High spectral efficiency 4-mode 400-km transmission using hybrid probabilistically and geometrically shaped 128QAM

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Science china(Technological Sciences) 2024年第5期67卷 1628-1630页

作者： DING JunJie yu JianJun wang Chen LONG Jianyu ZHU Min ZHANG Jiao Pervasive Communication Research Center Purple Mountain LaboratoriesNanjing 211111China Key Laboratory for Information Science of Electromagnetic Waves(MoE) Fudan UniversityShanghai 200433China

Wavelength division multiplexing(WDM)and space division multiplexing(SDM)based on few-mode fiber(FMF)and multi-core fiber(MCF)have been vigorously developed to increase the transmission capacity of optical communication networks[1–5].However,the mode crosstalk generated in the mode division multiplexing(MDM)system causes the correlation between different mode signals,which seriously damages the transmission ***,an effective multiple-input-multiple-output(MIMO)time domain or frequency domain equalizer should be used to eliminate the crosstalk between different mode signals.

关键词： crosstalk fiber multiplexing

Intelligent Dynamic Heterogeneous Redundancy Architecture for IoT Systems

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china Communications 2024年第7期21卷 291-306页

作者： Zhang Han wang yu Liu Hao Lin Hongyu Chen Liquan School of Cyber Science and Engineering Southeast UniversityNanjing 211102China purple mountain Laboratories Nanjing 211111China ZTE Corporation Nanjing 210012China Carbon Peaking&Carbon Neutrality Application Technology R&D Institute Nanjing University of Posts and TelecommunicationsNanjing 210002China

The conventional dynamic heterogeneous redundancy(DHR)architecture suffers from the security threats caused by the stability differences and similar vulnerabilities among the *** overcome these challenges,we propose an intelligent DHR architecture,which is more feasible by intelligently combining the random distribution based dynamic scheduling algorithm(RD-DS)and information weight and heterogeneity based arbitrament(IWHA)*** the proposed architecture,the random distribution function and information weight are employed to achieve the optimal selection of executors in the process of RD-DS,which avoids the case that some executors fail to be selected due to their stability difference in the conventional DHR ***,through introducing the heterogeneity to restrict the information weights in the procedure of the IWHA,the proposed architecture solves the common mode escape issue caused by the existence of multiple identical error output results of similar *** experimental results characterize that the proposed architecture outperforms in heterogeneity,scheduling times,security,and stability over the conventional DHR architecture under the same conditions.

关键词： dynamic heterogeneous redundancy heterogeneity IoT security security defense

THE MOTION PROPERTIES OF THE STARS CONFINED TO THE SYMMETRIC AXIS OF AN OSCILLATION KUZMIN DISK

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南京大学学报(自然科学) 1997年第4期 151-153页

作者： Fu Yanning 1,2) \ \ Sun Yisui 1) ( 1) department of Astronomy, nanjing University, 210008, nanjing, PRC 2) purple mountain observatory, Academia Sinica, 210008, nanjing, PRC)

ＴＨＥＭＯＴＩＯＮＰＲＯＰＥＲＴＩＥＳＯＦＴＨＥＳＴＡＲＳＣＯＮＦＩＮＥＤＴＯＴＨＥＳＹＭＭＥＴＲＩＣＡＸＩＳＯＦＡＮＯＳＣＩＬＬＡＴＩＯＮＫＵＺＭＩＮＤＩＳＫＦｕＹａｎｎｉｎｇ１，２）ＳｕｎＹｉｓｕｉ１）（１）Ｄ... 详细信息

ＴＨＥＭＯＴＩＯＮＰＲＯＰＥＲＴＩＥＳＯＦＴＨＥＳＴＡＲＳＣＯＮＦＩＮＥＤＴＯＴＨＥＳＹＭＭＥＴＲＩＣＡＸＩＳＯＦＡＮＯＳＣＩＬＬＡＴＩＯＮＫＵＺＭＩＮＤＩＳＫＦｕＹａｎｎｉｎｇ１，２）ＳｕｎＹｉｓｕｉ１）（１）ＤｅｐａｒｔｍｅｎｔｏｆＡｓｔｒｏｎ...

关键词： celestial mechanics galactic dynamics galaxy oscillation

THE FRAGMENTS OF COMET HYAKUTAKE (C/1996 B2)

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紫金山天文台台刊 1998年第2期 55-58页

作者： Chen Dao-han Zhao Ai-di Wu Qin-di Song Yi Fan Yi-xin(purple mountain observatory, Academia Sinica , nanjing 210008, china )Sun Shou-sheng Zhang Yan Sun Li-nan :(Qingdao Station of purple mountain observatory, Qingdao 266003, china)

Several fragments of Comet Hyakutake were observed in March and April of 1996. This leads to the impression that the splitting of Comet Hyakutake on a small scale occurred frequently. Data analysis points to a rotatio... 详细信息

关键词： Comet Hyakutake fragment rotation period.