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Steps Towards a Fully Automated Classification and Redshiftmeasurement Pipeline for LAMOST Spectra. I. Continuum level and wavelength estimation for galaxies

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chinese Journal of Astronomy and Astrophysics 2001年第6期1卷 563-572页

作者： A-li Luo and Yong-Heng Zhao national {2. Observatories, chinese academy of sciences, Beijing 100012 national astronomical Observatories Chinese Academy of Sciences Beijing 100012

The Large Sky-Area Multi-Object Spectroscopic Telescope (LAMOST) under construction by the national astronomical Observatories will yield up to four thousand multi-fiber spectra of stars and galaxies per field. The present series of papers describes the automated data-reduction pipe{2.ne currently being designed in order to cope with the anticipated flood of spectrographic data. In this pre{2.minary paper, we present an automated method for estimating the continuum level, the positions of strong {2.nes and the 4000 A break in galaxy spectra. In order to obtain detailed information on the continuum, we use a wavelet filter bank. After continuum fitting, our software searches for a 4000 A break and distinguishes between emission-{2.ne galaxies (ELGs) and non-ELGs according to whether the break is small or large. It then searches for strong {2.nes and measures the intensities of emission {2.nes and the equivalent widths of absorption {2.nes. For non-ELGs, the absorption {2.nes are identified automatically yielding redshift measurements.

关键词： methods: data analysis - techniques: spectroscopic - galaxies: emission lines - galaxies: absorption lines

Phylogeny of fireflies (Coleoptera: Lampyridae) inferred from mitochondrial 16S ribosomal DNA, with references to morphological and ethological traits

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Progress in Natural Science:Materials International 2006年第8期16卷 817-826页

作者： li Xueyan, YANG Shuang, XIE Meng and liANG Xingcai (Laboratory of Entomology, {2. Institute of Zoology, chinese academy of sciences, {2. 6502.3, china key Laboratory of Cellular and Molecular Evolution, {2. Institute of Zoology, chinese academy of sciences, {2. 6502.3, china Graduate School of the chinese academy of sciences, Beijing 100039, china) Laboratory of Entomology kunming Institute of Zoology chinese academy of sciences Kunming 650223 China Graduate School of the chinese academy of sciences Beijing 100039 China key Laboratory of Cellular and Molecular Evolution kunming Institute of Zoology Chinese Academy of Sciences Kunming 650223 China

We sequenced partial mitochondrial 16S ribosomal DNA (16S rDNA) of 18 firefly species from Southwest of china. Combined with homologous sequences previously reported, phylogenetic trees including Japanese, Korean and chinese species were reconstructed by neighbor-joining, maximum parsimony and Bayesian methods. All reconstructions agree on most nodes of the trees. Monophyly of Lampyridae is not supported because Rhagophthalmus ohbai in Rhagophthalmidae is included within it. Lamprigera, a genus placed unre{2.ably in Lampyrinae, shows a close relationship to Amydetinae. Monophyly of Lucio{2.nae is not supported because Pristolycus sagulatus (Lampyrinae) is included within it. In the Lucio{2.nae, monophyly of Curtos and Hotaria is well estab{2.shed, respectively, but both morphological and molecular data continue to indicate that Luciola is not monophyletic and its subdivision is indeed necessary. Within the Lampyrinae, both Pyrocoe{2.a and Diaphanes are not monophyletic, but monophyly of Pyrocoe{2.a + Diaphanes is well supported. Phylogeny of Diaphanes is discussed for the first time. Generic placement of a newly discovered species (Diaphanes pectinea{2.s {2. et {2.ang) sharing some characters of Pyrocoe{2.a and Diaphanes challenges the de{2.mitation of these two similar genera. With references to the firefly mating systems, we suggest that more emphases should be placed on those sexually selected characters such as antennal structure in taxonomy of Lampyridae.

关键词： Lampyridae mitochondrial 16S rDNA morphological and ethological traits phylogeny.

115GHz CO Emission from the IRAS Selected Star-Formation Regions

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天文研究与技术 1999年第S1期 358-362页

作者： Fu Haowen, Su Bumei, li Yongsheng (yunnan {2., The chinese academy of sciences,kunming 650011, china) (national astronomical Observatories, The chinese academy of sciences, Beijing 100012. china)

We report here on our search for CO emission in the direction of 70 IRAS sources with colours of star forming regions. CO emission was detected in 47 sources and 16 are newly detected. Emission line profiles that are non Gaussian (showing e. g. possible self absorption or wings) are identified. line parameters for detected sources and rms for non detections are presented. The data may serve as a basis for future research.

关键词： molecular clouds star formation young stellar objects

Model of Spectral Fluxes for Solar Spectrograph

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天文研究与技术 1999年第S1期 401-405页

作者： Cao Wenda, Song Qian (yunnan observatory, The {2., kunming 650011, china) (national astronomical Observatories, The {2., Beijing 100012. china)

Taking use of the solar spectrograph in yunnan observatory, we built a model to estimate the spectral fluxes of solar spectrograph with computer and confirmed the result by observations. The spectral fluxes in visible... 详细信息

关键词： Model of Spectral Fluxes for Solar Spectrograph

Magnetic Loop Oscillation Associated with a Large Type-Ⅳμ Burst and Millisecond Spike Emission

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天文研究与技术 1999年第S1期 424-427页

作者： Chen Xiaojuan, Ji Shuchen (Beijing astronomical observatory, The {2., Beijing 100080, china) (yunnan observatory, The {2., kunming 650011, china) (national astronomical Observatories, chinese {12. of S

A rare large Type Ⅳμ burst, appeared above active region NOAA/USAF 52.8 was observed at yunnan observatory with Phoenix Ⅱ Microwave Spectrometer at three frequencies (4 00, 2.84 and 1 42.GHz) on December 16, 1988. The burst consisted of 5 main peaks with a quasiperiod of 12.5 min, on which many complex mil{2.second spike emissions were superimposed. Within the first main peak there were 8 secondary peaks with a quasi period of 98s (at 4 00 GHz), 72. (2.84 GHz) and 60s (1 42.GHz). A semi quantitative explanation is given for the variation of the quasi period with frequency in terms of MHD modulated oscillations in the magnetic flux tube.

关键词： Type Magnetic Loop Oscillation Associated with a Large Burst and Millisecond Spike Emission

Observations of Microwave Ultra-Fast Absorption Phenomena Above Solar Active Region

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天文研究与技术 1999年第S1期 428-432页

作者： Chen Xiajuan, Ji Shuchen (Beijing astronomical observatory, The {2.,Beinjing 100080, china) (yunnan observatory, The {2., kunming 650011, china) (national astronomical Observatories, The chinese {12. o

While we process observational data of the Flares 2., two rare phenomena of microwave ultra fast absorption (MUFA) are found for the first time. They occurred at 3 67 GHz and 4 00 GHz in the atmospheric layers above both active regions of NOAA/USAF 4808 and 5060 in the interval 05 h50 m17 s～05 h50 m2. s UT on May 19, 1987 and 07 h38 m50 s～07 h38 m58 s UT on june 2., 1988, respectively. These absorption phenomena were observed with Phoenix Ⅱ Micowave Spectrometer at three frequencies (1 42. 2.84 and 3 67 GHz) and (1 42. 2.84 and 4 00 GHz) at yunnan {2.. Spike emissions appeared at both 2.84 GHz and 1 42.GHz. The notable observational characteristics of both absorption phenomena are given. A possible absorption mechanism of MUFA is discussed.

关键词： Observations of Microwave Ultra-Fast Absorption Phenomena Above Solar Active Region

Gyrosynchrotron Process of a Rare Large Type-Ⅳμ Burst Associated with Coronal Mass Ejection

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天文研究与技术 1999年第S1期 452-456页

作者： Ji Shuchen, Chen Xiaojuan (Beijing astronomical observatory, The {2., Beijing 100080, china) (yunnan observatory, The {2., kunming 650011, china) (national astronomical Observatories, The chinese {12.

A large Type Ⅳμ solar radio burst was observed at yunnan observatory on December 16, 1988. The burst was associated by a coronal mass ejection (CME) with the radio signature of Type Ⅱ and Type Ⅳ bursts. On the basis of Beijing Huairou magnetogram of AR52.8, power law distribution of electrons of the source region is calculated. It is suggested that the Type Ⅳμ burst associated with CME was due to the gyrosynchrotron radiation of high energy electrons trapped by magnetic field. Finally, some quantitative and qua{2.tative explanations are proposed.

关键词： Mass Associated with Coronal Mass Ejection Burst Gyrosynchrotron Process of a Rare Large Type

Observational Accuracy of Sunrise and Sunset Times in the Sixth Century china

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chinese Journal of Astronomy and Astrophysics 2006年第5期6卷 629-634页

作者： Yong li national astronomical Observatories Chinese Academy of Sciences Beijing 100012

The Daye Calendar was compiled in AD 597 in the Sui Dynasty. We investigate the records of sunrise and sunset times on the 2. solar-term days in the calendar. By converting the ancient chinese time units, Chen, ke and Fen to hour, minute and second, and carrying out a comparison between the ancient records and values computed with modem {2. theory, we find that the accuracy of solar measurements in the Sui period is remarkably high： for sunrise times, the average absolute deviation is 3.63 min （this value can be further reduced to 3.03 min when erroneous data are excluded）, and for sunset times it is 3.48 min. We also find that the observed sunrise and sunset times are strictly symmetrically distributed with respect to both the Winter Solstice and the Summer Solstice, with their deviations showing a similar symmetrical distribution as well. We give a discussion on the date of observation, the feature of the data, and possible reasons of the deviation.

关键词： history of astronomy -- astrometry -- solar-terrestrial relations -- methods statistical

Population information extraction in Chaohu watershed based on RS and GIS

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chinese Science Bulletin 2003年第2期48卷 181-183页

作者： liU Jianjun1,2.& li Chunlai3 1. Institute of Geochemistry, chinese academy of sciences, Guiyang 550002. china 2. Graduate School, chinese academy of sciences, Beijing 100039, china 3. national astronomical Observatories, chinese academy of sciences, Beijing 100012. china Correspondence should be addressed to liu Jianjun (e-mail: dhsliujj@ ***) Institute of Geochemistry Chinese Academy of Sciences Guiyang China Graduate School Chinese Academy of Sciences Beijing China national astronomical Observatories Chinese Academy of Sciences Beijing China

It is always difficult to extract population in-formation of small watershed during the region environment assessment. The report adopted compound areal interpola-tion to study the population in Chaohu watershed with the GIS technique and landuse interpretation data from remote sensing. The result indicated that the method is effective to extract population information of small watershed.

关键词：巢湖流域人口分布信息提取 RS GIS 小流域生态环境评价