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Stellar Populations of AGN-host Dwarf Galaxies Selected with Different Methods

Research in Astronomy and Astrophysics 2024年第6期24卷 52-67页

作者： Xiejin Li 赵应和 jinming bai Yunnan Observatories Chinese Academy of SciencesKunming 650216China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Radio Astronomy and Technology Chinese Academy of SciencesBeijing 100101China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of SciencesKunming 650011China

In this paper we investigate the stellar populations and star formation histories of 235 active galactic nucleus(AGN)-host dwarf galaxies,consisting of four samples identified separately with different methods(i.e.,radio,X-ray,mid-IR and variability),utilizing the synthesis code STARLIGHT and spectra from the Sloan Digital Sky Survey Data Release *** results show that the variability sample is the oldest,while the mid-IR sample is the youngest,for which the luminosity at 4020?is dominated(>50%)by the young population(t<10~8yr).The light-weighted mean stellar age of the whole sample is in general about 0.7 dex younger than the optical sample studied in Cai et *** compare the population results between fitting models with and without a power-law(PL)component and find that the neglect of a PL component would lead to an under-and over-estimation by 0.2 and0.1 dex for the light-and mass-weighted mean stellar age,respectively,for our sample of dwarf galaxies,which has a mean fractional contribution of~16%from the *** addition,we obtain further evidence for a possible suppression of star formation in the host galaxy by the central *** also find that there exists an anticorrelation between the extinction-corrected[O III]luminosity and light-weighted mean stellar age,confirming our previous finding that there is a physical connection between AGN and star-forming activities in AGN-host dwarfs.

关键词： galaxies:dwarf galaxies:active galaxies:stellar content

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Prospects of the Multi-channel Photometric Survey Telescope in the Cosmological Application of Type Ia Supernovae

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Research in Astronomy and Astrophysics 2024年第4期24卷 183-191页

作者： Zhenyu Wang Jujia Zhang Xinzhong Er jinming bai Yunnan Observatories Chinese Academy of SciencesKunming 650216China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of SciencesKunming 650216China International Centre of Supernovae Yunnan Key LaboratoryKunming 650216China South-Western Institute for Astronomy Research Yunnan UniversityKunming 650500China

The Multi-channel Photometric Survey Telescope(Mephisto)is a real-time,three-color photometric system designed to capture the color evolution of stars and transients *** telescope system can be crucial in cosmological distance measurements of low-redshift(low-z,z■0.1)Type Ia supernovae(SNe Ia).To optimize the capabilities of this instrument,we perform a comprehensive simulation study before its official operation is scheduled to *** considering the impact of atmospheric extinction,weather conditions,and the lunar phase at the observing site involving the instrumental features,we simulate light curves of SNe Ia obtained by *** best strategy in the case of SN Ia cosmology is to take the image at an exposure time of 130 s with a cadence of 3 *** this condition,Mephisto can obtain hundreds of high-quality SNe Ia to achieve a distance measurement better than 4.5%.Given the on-time spectral classification and monitoring of the Lijiang 2.4 m Telescope at the same observatory,Mephisto,in the whole operation,can significantly enrich the well-calibrated sample of supernovae at low-z and improve the calibration accuracy of high-z SNe Ia.

关键词： (stars:)supernovae:general (cosmology:)cosmological parameters telescopes

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基于RC-LSTM的雷达回波外推方法

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计算机集成制造系统 2024年第8期30卷 2962-2967页

作者：王友宁白金明刘琦南京信息工程大学计算机与软件学院教育部数字取证工程研究中心江苏南京210044 南京信息工程大学应用气象学院江苏南京210044

雷达回波外推是降水临近预报的重要手段,所用的方法分为数值预报与数据驱动预报。前者依托数学与物理模型,后者依托深度学习技术总结历史规律。尽管深度学习在气象预报中研究活跃,但实际应用仍面临挑战,尤其是精度问题。因此设计了一种... 详细信息

雷达回波外推是降水临近预报的重要手段,所用的方法分为数值预报与数据驱动预报。前者依托数学与物理模型,后者依托深度学习技术总结历史规律。尽管深度学习在气象预报中研究活跃,但实际应用仍面临挑战,尤其是精度问题。因此设计了一种雷达回波外推系统,应用所提出的残参卷积长短期记忆(RC-LSTM)模型,在使用规划采样的同时,为每一层堆叠的ConvLSTM单元添加了残差连接,使得模型在更深的同时保留原有小模型的学习能力,保证网络最大限度降低空间维度的历史信息损耗,从而提高长时效雷达回波外推的精度。

关键词：气象业务降水临近预报残参卷积长短期记忆雷达回波外推

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The correlation between the Doppler factor and broad line region luminosity in blazars

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Science China(Physics,Mechanics & Astronomy) 2012年第10期55卷 1938-1944页

作者： DU LeiMing bai jinming National Astronomical Observatories/Yunnan Observatory Chinese Academy of SciencesKunming 650011China Graduate University of Chinese Academy of Sciences Beijing 100049China Physics Department Yunnan Normal UniversityKunming 650050China

The disk-jet symbiosis is a fundamental problem in our understanding of the Active Galactic Nuclei （AGN）. We explore the relation between the Doppler factors d of the jet of blazars and their broad line region luminosity LBLR. Since different methods measuring δ might differ substantially, we use data obtained from 3 independent methods and compile 3 samples of sources for each of them, respectively. Two samples consist of blazars, that is, Flat Spectrum Radio Quasars （FSRQs） and BL Lacertae objects （BL Lacs）, and the other consists of BL Lacs. dis one of the most important jet properties and LBLR is thought to be the proxy of the accretion power. Correlation analysis to these samples shows that there exists a significant correlation between δ and LBLR, which supports the idea that the jet powering process is closely linked with the accretion process and provides new evidence for disk-jet connection. Furthermore, the results are consistent with the idea that the Blandford-Znajek mechanism is sufficient for BL Lacs and a hybrid model is needed for FSRQs.

关键词： Doppler factor broad line region luminosity jet power accretion power

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Discovery of two broad absorption line quasars at redshift about 4.75 using the Lijiang 2.4 m telescope

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Science China(Physics,Mechanics & Astronomy) 2015年第9期58卷 90-94页

作者： YI WeiMin WU XueBing WANG FeiGe YANG JinYi YANG Qian bai jinming Yunnan Observatories Chinese Academy of Sciences University of the Chinese Academy of Sciences Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of Sciences Department of Astronomy School of Physics Peking University Kavli Institute for Astronomy and Astrophysics Peking University

The ultraviolet broad absorption lines have been seen in the spectra of quasars at high redshift, and are generally considered to be caused by outflows with velocities from thousands kilometers per second to one tenth of the speed of light. They provide crucial implications for the cosmological structures and physical evolutions related to the feedback of active galactic nuclei(AGNs).Recently, through a dedicated program of optically spectroscopic identifications of selected quasar candidates at redshift 5 by using the Lijiang 2.4 m telescope, we discovered two luminous broad absorption line quasars(BALQSOs) at redshift about 4.75. One of them may even have the potentially highest absorption Balnicity Index(BI) ever found to date, which is remarkably characterized by its deep, broad absorption lines and sub-relativistic outflows. Further physical properties, including the metal abundances,variabilities, evolutions of the supermassive black holes(SMBH) and accretion disks associated with the feedback process, can be investigated with multi-wavelength follow-up observations in the future.

关键词： high-redshift active galactic nuclear(AGN) broad absorption line quasar(BALQSO) outflow

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Research on Problems and Countermeasures in the Cooperation between Higher Vocational Colleges and Enterprises

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International English Education Research 2017年第3期 4-6页

作者： bai jinming Zhengzhou University of Science and Technology No. 1 Xueyuan Road Mazhai TownErqi District Zhengzhou City Henan Province China 450064

As practical teaching receives higher value in the cultivation of college talents, the cooperation between higher vocational colleges and enterprises becomes a necessity to practice practical teaching. The successful cooperation bases on its management and operation. Establishing and perfecting the relevant laws and regulations and the inspection appraisal system can ensure the cooperation go smoothly. The government should coordinate the relationship among the government functional departments, colleges and enterprises, clarify the dominant and main body status of college-enterprise cooperation, improve the initiative and enthusiasm of all parties, as to ensure the coordinated development of college-enterprise cooperation. The old system,mechanism and conventions should be broken to promote talents＇ cooperation. The building of ＂double type＂ teachers should be intensified to finally achieve the great goal that cultivating the qualified builders and successors for the socialist country.

关键词： higher vocational colleges college-enterprise cooperation problems and countermeasures

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CYP17 T27C polymorphism and prostate cancer risk: a meta-analysis based on 31 studies

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The Journal of Biomedical Research 2010年第3期24卷 233-241页

作者： Bingbing Wei Yunyun Zhang Bo Xi Junkai Chang jinming bai Jiantang Su Department of Urology the First Affiliated Hospital of Nanjing Medical University Nanjing 210029 Jiangsu Province China Department of Neurology the First Affiliated Hospital of Nanjing Medical University Nanjing 210029 Jiangsu Province China Graduate School Peking Union Medical College Beijing 100730 China Department of Epidemiology Capital Institute of Pediatrics Beijing 100020 China

Objective：The cytochrome P450 17α-hydroxylase（CYP17）plays a vital role in androgen biosynthesis.A T-to-C polymorphism in the 5＇promoter region of CYP17 has been implicated as a risk factor for prostate cancer,but the results of individual studies are inconclusive or *** derive a more precise estimation of the relationship,we performed an updated meta-analysis from 31 studies based on 27 ***：A comprehensive search was conducted to examine all the eligible studies of CYP17 polymorphism and prostate cancer *** used odds ratios（ORs）with 95%confidence intervals（CIs）to assess the strength of the ***：Overall,individuals with CC/CT genotype were not associated with prostate cancer risk （CC ***：OR=1.03,95%CI=0.86-1.24,P=0.72,P heterogeneity 〈0.0001;CT ***：OR=0.99,95%CI=0.87- 1.12,P=0.88,P heterogeneity =0.0006）.In the stratified analysis by ethnicity,there was a significantly increased risk of prostate cancer among individuals of African descent under the recessive model（OR=1.56,95%CI=1.01- 2.39,P=0.04,P heterogeneity =0.65）.Conclusion：This meta-analysis suggested that CYP17 polymorphism might be associated with prostate cancer risk among individuals of African descent.

关键词： CYP17 prostate cancer meta-analysis

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The relationship of extended radio power and broad emission line luminosity in blazars

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Science China(Physics,Mechanics & Astronomy) 2010年第S1期53卷 240-243页

作者： LIU HongTao & bai jinming National Astronomical Observatories/Yunnan Observatory,Chinese Academy of Sciences,Kunming 650011,China National Astronomical Observatories/Yunnan Observatory Chinese Academy of Sciences Kunming China

The relationship between broad line luminosity LBLR and extended radio power PE is *** the log PE-log LBLR diagram,FSRQs populate the region of higher luminosity relative to BL Lacs,and FR II BL Lacs are between FSRQs and FR I BL *** these blazars,there is a significant correlation between LBLR and *** regression line scales as PE ∝ L0B.L87R ± *** slope of this scaling relation is consistent with that derived from the simple theoretical ***,the unification of BL Lacs and FRSQs into a single population finds a statistical basis,and a disk-jet symbiosis in blazars is *** II BL Lacs are probably at an intermediate stage in the sequence from FSRQs to BL Lacs with FR I BL Lacs at the end of this sequence.

关键词： accretion black hole physics BL Laceratae objects:general galaxies:nuclei quasars:general

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多群落粒子群优化供应链数据中心任务调度

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应用科学学报 2023年第3期41卷 419-430页

作者：曾磊白金明刘琦南京信息工程大学计算机学院江苏南京210044 南京信息工程大学应用气象学院江苏南京210044 南京信息工程大学数字取证工程研究中心江苏南京210044

针对数据中心规模和任务需求不断增加带来的服务效率降低等问题,提出了一种负载均衡多群落粒子群优化任务调度方法。通过改进的适应度函数对任务的最大完工时间和各机器完工时间方差进行组合优化以提升集群的负载均衡性;利用新的自适应... 详细信息

针对数据中心规模和任务需求不断增加带来的服务效率降低等问题,提出了一种负载均衡多群落粒子群优化任务调度方法。通过改进的适应度函数对任务的最大完工时间和各机器完工时间方差进行组合优化以提升集群的负载均衡性;利用新的自适应惯性权重函数改进粒子搜索效率,提升算法收敛速率;采取新的粒子初始化方法提高初始解的质量和多样性,并利用多群落粒子协同搜索使得最终结果更加接近最优解。在阿里巴巴数据中心的公开数据集上对算法性能进行了验证和对比,实验结果表明,该方法能够提高数据中心在多样化供应链环境下的任务调度效率。

关键词：粒子群优化供应链管理数据中心任务调度负载均衡

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A puzzle of the radio-quiet quasar PG 1407+265:Are optical and X-ray emissions produced from a relativistic jet?

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Science China(Physics,Mechanics & Astronomy) 2011年第1期54卷 183-186页

作者： CHEN Liang 1,2,3 & bai jinming 1,2 1 National Astronomical Observatories/Yunnan Observatory,Chinese Academy of Sciences,Kunming 650011,China 2 Key Laboratory for the Structure and Evolution of Celestial Objects,Chinese Academy of Sciences,Kunming 650011,China 3 Graduate University of Chinese Academy of Sciences,Beijing 100049,China Chinese Academy of Sciences National Astronomical Observatories/Yunnan Observatory Kunming China (GRID:grid.9227.e) (ISNI:***) Chinese Academy of Sciences Key Laboratory for the Structure and Evolution of Celestial Objects Kunming China (GRID:grid.9227.e) (ISNI:***) Graduate University of Chinese Academy of Sciences Beijing China (GRID:grid.458514.9) Chinese Academy of Sciences National Astronomical Observatories/Yunnan Observatory Kunming China (GRID:grid.9227.e) (ISNI:***) Chinese Academy of Sciences Key Laboratory for the Structure and Evolution of Celestial Objects Kunming China (GRID:grid.9227.e) (ISNI:***)

PG 1407+265 is a radio quiet quasar that has a relativistic *** this report,we show some peculiar properties of its optical and X-ray emissions,which indicate possible non-thermal origins produced from the *** use a simple synchrotron + synchrotron self Compton (SSC) model to fit the emissions with different ratios of energy densities between the magnetic field and electrons (η≡U B/U e),which predicts a different γ-ray *** First LAT AGN Catalog (1LAC) did not include PG 1407+265,which indicates an upper limit of γ-ray *** upper limit constrains the ratio to be unreasonably large (η≥10 4-5).This inversely indicates that the optical and X-ray emissions may not be produced from the beaming *** discuss the physical implications of these results.

关键词： active galactic nuclei jet non-thermal emission PG 1407+265

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