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Spatial distribution analysis on climatic variables in northeast China

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Journal of Environmental Sciences 2001年第2期13卷 247-251页

作者： SHANG Zong-Bo GAO Qiong YANG Dian-An YANG Zheng-Yu Laboratory of Quantitative Vegetation Ecology Institute of Botany The Chinese Academy of Sciences Beijing 100093 China

Information ecology is a new research area of modern ecology. Here describes the spatial distribution analysis methods of four sorts of climatic variables, i.e. temperature, precipitation, relative humidity and sunshine fraction in Northeast China. First, digital terrain models was built with large scale maps and vector data. Then trend surface analysis and interpolation method were used to analyze the spatial distribution of these four kinds of climatic variables at three temporal scale: (1) monthly data; (2) mean monthly data of thirty years, and (3) mean annual data of thirty years. Ecological information system were used for graphics analysis on the spatial distribution of these climatic variables.

关键词： spatial distribution analysis climatic variables trend surface analysis information ecology

Experimental test of error-disturbance uncertainty relation with continuous variables

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Photonics Research 2019年第11期7卷 I0012-I0016页

作者： Yang Liu Haijun Kang Dongmei Han Xiaolong Su Kunchi Peng State Key Laboratory of Quantum Optics and Quantum Optics Devices Institute of Opto-ElectronicsShanxi UniversityTaiyuan 030006China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China

The uncertainty relation is one of the fundamental principles in quantum mechanics and plays an important role in quantum information science. We experimentally test the error-disturbance uncertainty relation(EDR) with continuous variables for Gaussian states. Two incompatible continuous-variable observables, amplitude and phase quadratures of an optical mode, are measured simultaneously using a heterodyne measurement *** EDR values with continuous variables for coherent, squeezed, and thermal states are verified *** experimental results demonstrate that Heisenberg’s EDR with continuous variables is violated, while Ozawa’s and Branciard’s EDRs with continuous variables are validated.

关键词： continuous relation variables

Complete f-moment Convergence for Widely Orthant Dependent Random variables and Its Application in Nonparametric Models

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Acta Mathematica Sinica,English Series 2019年第12期35卷 1917-1936页

作者： Chao LU Zhuang CHEN Xue Jun WANG School of Mathematical Sciences Anhui University

In this paper,we study the complete f-moment convergence for widely orthant dependent(WOD,for short)random variables.A general result on complete f-moment convergence for arrays of rowwise WOD random variables is *** applications,we present some new results on complete f-moment convergence for WOD random *** also give an application to nonparametric regression models based onWOD errors by using the complete convergence that we ***,the choice of the fixed design points and the weight functions for the nearest neighbor estimator are proposed,and a numerical simulation is provided to verify the validity of the theoretical result.

关键词： Widely orthant dependent random variables complete f-moment convergence complete convergence complete consistency

Variable binaries and variables in binaries in the Binary star DataBase

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Research in Astronomy and Astrophysics 2019年第3期19卷 7-12页

作者： Dana Kovaleva Oleg Malkov Pavel Kaygorodov Institute of Astronomy Russian Academy of Sciences

The Binary star DataBase(BDB, http://***) combines data from catalogs of binary and multiple stars of all observational types. There is a number of ways for variable stars to form or to be a part of binary or multiple... 详细信息

关键词： astronomical data bases-stars binaries general-stars variables general

Mid-infrared Period-Luminosity Relations of Gaia DR3 Long Period variables

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Research in Astronomy and Astrophysics 2024年第7期24卷 56-70页

作者： Xiaohan Chen Xiaodian Chen Licai Deng Shu Wang Tianlu Chen Department of Physics College of ScienceTibet UniversityLhasa 850000China Key Laboratory of Cosmic Rays(Tibet University) Ministry of EducationLhasa 850000China CAS Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China School of Astronomy and Space Science University of the Chinese Academy of SciencesBeijing 100049China Department of Astronomy China West Normal UniversityNanchong 637009China Institute for Frontiers in Astronomy and Astrophysics Beijing Normal UniversityBeijing 102206China

Long period variable(LPV)stars are very promising distance indicators in the infrared *** selected asymptotic giant branch(AGB)stars in the Large and Small Magellanic Cloud(LMC and SMC)from the Gaia Data Release 3 LPV catalog,and classified them into oxygen-rich(O-rich)and carbon-rich(C-rich)AGB *** the Wide-field Infrared Survey Explorer database,we determined the W1-and W2-band period-luminosity relations(PLRs)for each pulsation-mode sequence of AGB *** dispersion of the PLRs of O-rich AGB stars in sequences C'and C is relatively small,around 0.14 *** PLRs of LMC and SMC are consistent in each *** the W2 band,the PLR of large-amplitude C-rich AGB stars is steeper than that of small-amplitude C-rich AGB stars,due to their more circumstellar *** two methods,we find that some PLR sequences of O-rich AGB stars in the LMC are dependent on *** coefficients of the metallicity effect areβ=-0.533±0.213 mag dex~1andβ=-0.767±0.158 mag dex~1for sequence C in W1 and W2 bands,*** significance of the metallicity effect in W1 band for the four sequences is 2.2-3.5σ.Both of these imply that distance measurements using O-rich Mira may need to take the metallicity effect into account.

关键词： stars variables general-stars distances-infrared stars

Seasonal Variation of Environmental variables and Phytoplankton Community Structure and Their Relationship in Liaodong Bay of Bohai Sea,China

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Journal of Ocean University of China 2018年第4期17卷 864-878页

作者： YANG Guojun WU Zhongxin SONG Lun LU Xiaoqian College of Fisheries and Life Science Dalian Ocean UniversityDalian 116023China Center for Marine Ranching Engineering Science Research of Liaoning Province Dalian Ocean UniversityDalian 116023China College of Marine Science and Environment Dalian Ocean UniversityDalian 116023China Liaoning Ocean and Fisheries Science Research Institute Dalian 116023China

In this paper, systematic studies on the changes in concentrations of the environmental factors and the net-phytoplankton community, and the relationship between them in the Liaodong Bay, Bohai Sea during 2013 are presented. The PCA results showed that higher levels of nutrients and dissolved heavy metals in the river-estuary-bay system were closely related to the river runoff. Since the influences of industrial and anthropogenic activities, the Liaodong Bay coastal areas are facing a huge environmental challenge of nutrients and heavy metal pollution. Net-phytoplankton community structure showed obvious seasonal succession, among which the dominant and(or) key species were the main factors affecting community structure change and stability. Under certain environmental conditions, the dominant species and(or) key species dominated the phytoplankton community structure succession. The Bio-ENV results suggested that the seawater temperature, nutrient, Cu, Pb, Zn, and Cd in Liaodong Bay are important environmental variables that affect the phytoplankton community structure. Anthropogenic activities have significantly contributed to the changes in concentrations of environmental factors and the net-phytoplankton community structure and stability, and the relationship between them.

关键词： Liaodong Bay environmental variables eutrophication trace metals phytoplankton community ecological stability

Sharp L^p decay of oscillatory integral operators with certain homogeneous polynomial phases in several variables

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Science China Mathematics 2019年第4期62卷 649-662页

作者： Shaozhen Xu Dunyan Yan School of Mathematical Sciences University of Chinese Academy of Sciences

In this paper, we obtain the L^p decay of oscillatory integral operators T_λ with certain homogeneous polynomial phase functions of degree d in(n + n)-dimensions; we require that d > 2 n. If d/(d-n) < p < d/n,the decay is sharp and the decay rate is related to the Newton distance. For p = d/n or d/(d-n), we obtain the almost sharp decay, where "almost" means that the decay contains a log(λ) term. For otherwise, the L^p decay of T_λ is also obtained but not sharp. Finally, we provide a counterexample to show that d/(d-n) p d/n is not necessary to guarantee the sharp decay.

关键词： oscillatory integral operators sharp L^p decay several variables Newton distance

variables and Constants in Literature:A Discussion of “Extrinsic Research” and “Intrinsic Research”

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Social Sciences in China 2023年第3期44卷 74-89页

作者： Chen Zhongyi Li Guanghui Foreign Studies College Hunan Normal University

The variables and constants in literature are as difficult to separate and understand as the intricacies of quantum *** is the basic mode of literary existence and also an important precondition for the longevity of literary ***,since the late 19th century,literary currents have been turbulent,and wave upon wave of critical theory has evinced a discord between“the intrinsic and the extrinsic,”even amounting to mutual exclusion,with the result that literary constants or common sense have been intentionally or unintentionally *** is not only clear evidence of the accelerated development of human society,but also the result of the interaction of many complex *** this reason,a dialectical analysis of the relationship between variables and constants or“extrinsic research”and“intrinsic research”has long been a major issue not easily avoided.

关键词： literary principle variables constants extrinsic research intrinsic research

A Note on the Transformation of variables of KP Equation, Cylindrical KP Equation and Spherical KP Equation

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Communications in Theoretical Physics 2019年第2期71卷 170-174页

作者： Chun-Ping Liu Institute of Mathematics Yangzhou UniversityYangzhou 225002China

In a recent article(Commun. Theor. Phys. 67(2017) 207), three(2+1)-dimensional equations — KP equation, cylindrical KP equation and spherical KP equation, have been reduced to the same Kd V equation by using different transformation of variables, respectively. In this short note, by adding an adjustment item to original transformation, three more general transformation of variables corresponding to above three equations have been *** the solutions of the Kd V equation into our transformation of variables, more new exact solutions of the three(2+1)-dimensional equations can be obtained.

关键词： transformation of variables KP equation cylindrical KP equation spherical KP equation