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Adaptive quasi-likelihood estimate in generalized linear models

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Science china Mathematics 2005年第6期48卷 829-846页

作者： CHEN Xia & CHEN Xiru School of Mathematics and Statistics, Wuhan university, Wuhan 43.072, china graduate School, {3. academy of Science, beijing 100049, china School of Mathematics and Statistics Wuhan University Wuhan China graduate School Chinese Academy of Science Beijing China

This paper gives a thorough theoretical treatment on the adaptive quasilikelihood estimate of the parameters in the generalized linear models. The unknown covariance matrix of the response variable is estimated by the sample. It is shown that the adaptive estimator defined in this paper is asymptotically most efficient in the sense that it is asymptotic normal, and the covariance matrix of the limit distribution coincides with the one for the quasi-likelihood estimator for the case that the covariance matrix of the response variable is completely known.

关键词： generalized linear models, quasi likelihood estimate, adaptive estimate.

Input function and simulated distributions of tritium in the North Pacific

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Science china Earth sciences 2010年第3期53卷 441-453页

作者： BA Qi1,2 & XU YongFu1 1 State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry, Institute of Atmospheric Physics, chinese academy of sciences, {3. 100029, china 2 graduate university of chinese academy of sciences, beijing 100049, china State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China graduate university of chinese {3. of sciences Beijing China

An ocean general circulation model (OGCM) of the North Pacific with a southern open boundary condition is used to simulate the distribution and transport of tritium in the North Pacific. First, the observed tritium in precipitation dataset of GNIP/ISOHIS is chosen, and used to develop an input function of tritium for the model domain from 1951 to 1997 in terms of the triangulation for interpolation. Then, the input function is used as an upper flux for the tritium model. The OGCM with tritium is integrated for 47 years with the initial condition of zero tritium concentrations. Compared with the observations from GEOSECS and WOCE, the model generates a meridional gradient of surface tritium concentrations and the high tritium concentrations in the subsurface layer, which is consistent with that indicated in the observations. The simulated time series of total tritium fluxes from the atmosphere to the ocean shows a spike in 1963. The total inventory of tritium in the ocean changes slowly with time after 1975. Tritium enters the higher-latitude region, and then is mainly transported by the subsurface process towards the equatorial region, which is well simulated in the model. However, the difference mainly occurs at 3.°N–40°N, which can be seen also in the simulation of CFCs. This difference may partly originate from the insufficient description of physical processes in the OGCM. Nevertheless, some uncertainties exist in the development of the tritium input function, which can also influence the simulated results.

关键词： North Pacific basin-wide ocean general circulation model tritium input function tritium distributions

Vertical adaptive radiation in ocean Prochlorococcus:Evolutionary implications of the Ch1 b/a ratio from molecular evidence

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Progress in Natural Science:Materials International 2009年第11期19卷 1561-1568页

作者： Song Qin~(a,*),Yinchu Wang~(a,b) a Yantai Institute of Coastal Zone Research for Sustainable Development,chinese academy of sciences,Yantai 264003.{3. b graduate university of chinese academy of sciences,beijing 100049,{3. Yantai Institute of Coastal Zone Research for Sustainable Development Chinese Academy of Sciences Yantai 264003 China graduate university of chinese {3. of sciences Beijing 100049 China

Prochlorococcus is a marine cyanobacterium of global *** ecotypes are adapted to either high-light(HL) or low-light (LL) *** ratio between chlorophyll(Chl) a and b is a distinguishing characteristic of these two ***,how this ratio evolved in Prochlorococcus during this ecotype differentiation remains *** analyses reveal that the ancestor of Prochlorococcus was typically low-light *** LL ecotype showed a stagnant evolution,and the HL ecotype was recently *** was an adaptive radiation after directional evolution in the Chl bla ratio *** in chlorophyllide a oxygenase(CAO) and positive selection on Clp protease contributed to the directional evolution of *** recombinant fragments of CAO were correlated with a large group of shared coevolving *** of positive selection was found in both subunits of *** bla ratio evolution,as annotated by molecular evidence,appears to be among the crucial reasons that explain how Prochlorococcus has become the dominant photosynthetic organism in the ocean.

关键词： Prochlorococcus Ch1 b/a ratio Adaptive evolution Trait evolution Ecotype differentiation

Observation constraints of the hard X-ray modulation telescope HXMT

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Science china(Physics,Mechanics & Astronomy) 2010年第S1期53卷 31-35页

作者： LU Yu1,2,ZHANG WenZhao3.QU JinLu1,SONG LiMing1,GAO Jian3.ZHANG HongMei4 & OU Ge4 1 Key Laboratory of Particle Astrophysics,Institute of High Energy Physics,chinese academy of sciences,{3. 100049,china 2 graduate university of chinese academy of sciences,{3. 100049,china 3.Department of Astronomy,{3. Normal university,{3. 100875,china 4 Computing Center,Institute of High Energy Physics,chinese academy of sciences,{3. 100049,china Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing China graduate university of chinese {3. of sciences Beijing China Department of Astronomy Beijing Normal University Beijing China Computing Center Institute of High Energy Physics Chinese Academy of Sciences Beijing China

The hard X-ray modulation telescope HXMT is a low orbit X-ray space telescope whose main science goals are to accomplish a hard X-ray all sky survey and to study timing and spectral characteristics of X-ray *** has three kinds of science instruments:the high energy X-ray detector(HE),the medium energy X-ray detector(ME) and the low energy X-ray detector(LE).The observation schedule of HXMT is a key to achieving the science goal of HXMT,and the analysis of the observation constraints is one of the first tasks in making the observation *** paper analyzes how the observation constraints influence the sky visibility and the visible time distribution of X-ray sources and discusses the schedule strategy with regard to the observation constraints.

关键词： HXMT observation constraints sky visibility

New universal matK primers for DNA barcoding angiosperms

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Journal of Systematics and Evolution 2011年第3期49卷 176-181页

作者： 1,2Jing YU 1Jian-Hua XUE 1Shi-Liang ZHOU* 1(State Key Laboratory of Systematic and Evolutionary Botany,Institute of Botany,chinese academy of sciences,{3. 100093.china) 2(graduate university of the chinese academy of sciences,{3. 100049,china) (State Key Laboratory of Systematic and Evolutionary Botany Institute of Botany Chinese Academy of Sciences Beijing 100093 China) (graduate university of the chinese {3. of sciences Beijing 100049 China)

The chloroplast maturase K gene(matK) is one of the most variable coding genes of angiosperms and has been suggested to be a "barcode" for land ***,matK exhibits low amplification and sequencing rates due to low universality of currently available primers and mononucleotide *** resolve these technical problems,we evaluated the entire matK region to find a region of 600-800 bp that is highly variable,represents the best of all matK regions with priming sites conservative enough to design universal primers,and avoids the mononucleotide *** careful evaluation,a region in the middle was chosen and a pair of primers named matK472F and matK1248R was designed to amplify and sequence the matK fragment of approximately 776 *** region encompasses the most variable sites,represents the entire matK region best,and also exhibits high amplification rates and quality of *** universality of this primer pair was tested using 58 species from 47 families of angiosperm *** primers showed a strong amplification(93.1%) and sequencing(92.6%) successes in the species *** propose that the new primers will solve,in part,the problems encountered when using matK and promote the adoption of matK as a DNA barcode for angiosperms.

关键词： angiosperm DNA barcoding matK primer.

Neogene eolian deposits within the West Qinling Mountains:Climatic and tectonic implications

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chinese Science Bulletin 2010年第15期55卷 1483-1487页

作者： GE JunYi 1,2 & GUO ZhengTang 3.1 State Key Laboratory of Loess and Quaternary Geology (SKLLQG),Institute of Earth Environment,chinese academy of sciences,Xi’an 710075,{3. 2 graduate university of chinese academy of sciences,beijing 100049,{3. 3.Key Laboratory of Cenozoic Geology and Environment,Institute of Geology and Geophysics,chinese academy of sciences,beijing 100029,{3. State Key Laboratory of Loess and Quaternary Geology (SKLLQG) Institute of Earth Environment Chinese Academy of Sciences Xi’an China graduate university of chinese {3. of sciences Beijing China Key Laboratory of Cenozoic Geology and Environment Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China

The Qinling Mountains constitute a key climate barrier between southern and northern *** recent investigations revealed widely spread eolian deposits of Neogene age mantling the piedmont highlands of the intermountain basins within West ***-mammalian fossils dated a 150.2 m section (NL-VI) near Xihe for the late Miocene to Pliocene (～10-4 Ma).Soil micromorphology,grain-size and geochemical analysis consistently define typical loess-soil alternations for the upper (0-66 m) and lower (98-150.2 m) parts of the section,with the middle section (66-98 m) having been affected by episodic slope *** results add important insights to the earlier studies about the widespread eolian deposition in northern china during the Miocene,prior to 8 *** also suggest that the basic configuration of the ridges and inter-ridge basins of West Qinling has already formed by ～10 *** well-preserved eolian deposits are unlikely to support intense substratum deformation and rapid uplift of West Qinling since the late Miocene.

关键词：秦岭山脉风尘堆积构造意义气候新近纪晚中新世地球化学分析风尘沉积

Simulation of aerodynamic performance affected by vortex generators on blunt trailing-edge airfoils

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Science china(Technological sciences) 2010年第1期53卷 1-7页

作者： YANG Ke1,2,ZHANG Lei1,3.& XU JianZhong1,2 1 Institute of Engineering Thermophysics,chinese academy of sciences,{3. 100190,china 2 Key Laboratory of Wind Energy Utilization,chinese academy of sciences,{3. 100190,china 3.graduate School of chinese academy of sciences,{3. 100190,china Institute of Engineering Thermophysics Chinese Academy of Sciences Beijing China Key Laboratory of Wind Energy Utilization Chinese Academy of Sciences Beijing China graduate School of chinese academy of {3. Beijing China

An investigation was carried out by numerical simulation on a wind turbine airfoil and a blunt trailing-edge airfoil with and without vortex generators (VGs), and the performance of the airfoils was analyzed. By the simulation of airfoil DU 91-W2-250 it was verified that the numerical method and model were credible. Based on this airfoil, a new one with a blunt trailing edge of 6% chord was blended by symmetrically adding thickness, and its characteristics curves were obtained through computing at key angles of attack. Additionally, the pressure distribution on blended airfoil was analyzed by comparing to the airfoil without blend. The interaction of streamwise vortices induced by VGs with trailing vortex or separation vortex was considered, followed by the uncovery of how VGs can suppress the boundary layer separation.

关键词： vortex generators airfoil blunt trailing-edge

fMRI time series analysis based on stationary wavelet and spectrum analysis

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Progress in Natural Science:Materials International 2006年第11期16卷 1171-1176页

作者： ZHI Lianhe~ 1,2,3., ZHAO Xia~4, SHAN Baoci~1**, PENG Silong~5, YAN Qiang~1, YUAN Xiuli~1 and TANG Xiaowei~ 1,6 (1. Key Laboratory of Nuclear Analysis Techniques, Institute of High Energy Physics, chinese academy of sciences,{3., china 2. graduate School of chinese academy of sciences,{3., china 3. Department of Physics, Zhoukou Normal university, Zhoukou 466100, china 4. Research Imaging Center, university of Texas Health Science Center, San Antonio, Texas 78229, USA 5. National ASIC Design and Engineering Center, Institute of Automation, chinese academy of sciences,{3., china 6. Department of Physics, Zhejiang university, Hangzhou 3.0027, china) Key Laboratory of Nuclear Analysis Techniques Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China graduate School of chinese academy of {3. Beijing 100049 China Department of Physics Zhoukou Normal University Zhoukou 466100 China Research Imaging Center University of Texas Health Science Center San Antonio TX 78229 United States National ASIC Design and Engineering Center Institute of Automation Chinese Academy of Sciences Beijing 100049 China Department of Physics Zhejiang University Hangzhou 310027 China

The low signal to noise ratio (SNR) of functional MRI (fMRI) prefers more sensitive data analysis methods. Based on stationary wavelet transform and spectrum analysis, a new method with high detective sensitivity was developed for analyzing fMRI time series, which does not require any prior assumption of the characteristics of noises. In the proposed method, every component of fMRI time series in the different time-frequency scales of stationary wavelet transform was discerned by the spectrum analysis, then the components from noises were removed using the stationary wavelet transform, finally the components of real brain activation were detected by cross-correlation analysis. The results obtained from both simulated and in vivo visual experiments illustrated that the proposed method has much higher sensitivity than the traditional cross-correlation method.

关键词： fMRI stationary wavelet transform spectrum analysis data analysis.

Relationship between precipitation and the infiltration depth over the middle and lower reaches of the Yellow River and Yangtze-Huaihe River Valley

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Progress in Natural Science:Materials International 2008年第9期18卷 1123-1128页

作者： Zhixin Hao a, Jingyun Zheng a, Quansheng Gea,, Xifeng Guoa,b a Institute of Geographical sciences and Natural Resources Research, chinese academy of sciences, 11A, Datun Road Anwai, Chaoyang District, beijing 100101, china b graduate university of chinese academy of sciences, beijing 100049, china Institute of Geographical sciences and Natural Resources Research Chinese Academy of Sciences 11A Datun Road Anwai Chaoyang District Beijing 100101 China graduate university of chinese {3. of sciences Beijing 100049 China

The purpose of the paper is to extract and make the best use of rainfall information contained in the chinese historical archives of Qing Dynasty, and reconstruct the precipitation series during *** study followed the Yu-Fen-Cun (rainfall infiltration depth) observation method in Qing Dynasty, to conduct soil infiltration experiment under the natural rainfall conditions during *** related parameters, such as precipitation, intensity, initial soil moisture content and infiltration depth have been measured at 10 stations (east of 105°E, 3.°-40°N) with representative climatic conditions and soil physical texture in the middle and lower reaches of the Yellow River and Yangtze-Huaihe River *** statistical results indicate that precipitation is the primary infiuencing factor to infiltration depth and is positively correlated with the infiltration ***, the efiects of every factor on infiltration depth are significantly difierent between the middle and lower reaches of the Yellow River and Yangtze-Huaihe River ***, the relationship equations of precipitation and infiltration depth are established for each site, most of which can pass over 60% of the variance explanations and provide quantitative models to reconstruct the precipitation series using Yu-Fen-Cun records in Qing Dynasty.

关键词： Middle and lower reaches of the Yellow River and Yangtze-Huaihe River Valley Precipitation Infiltration depth Yu-Fen-Cun Climate reconstruction