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Normal Families and Uniqueness of Entire Functions and Their Derivatives

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Acta Mathematica Sinica,English Series 2007年第6期23卷 973-982页

作者： jiang ming CHANG Department of Mathematics Changshu Institute of Technology Changshu 215500 P. R. China Department of Mathematics Nanjing Normal University Nanjing 210097 P. R. China Department of Applied Mathematics South China Agricultural University Guangzhou 510642 P. R. China Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100800 P. R. China

Let f be a nonconstant entire function; let k ≥ 2 be a positive integer; and let a be a nonzero complex number. If f（z） = a→f′（z） = a, and f′（z） = a →f^（k）（z） = a, then either f = Ce^λz ＋ a or f = Ce^λz ＋ a（λ - 1）/）λ, where C and ）, are nonzero constants with λ^k-1 = 1. The proof is based on the Wiman-Vlairon theory and the theory of normal families in an essential way.

关键词： entire function normal family unicity theorem

IMAGE QUALITY ASSESSMENT BASED ON CONTOUR AND REGION

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Journal of Computational Mathematics 2016年第6期34卷 705-722页

作者： Chen Huang ming jiang Tingting jiang LMAM School of Mathematical Sciences Beijing International Center for Mathematical Research and Cooperative Medianet Innovation Center Peking University Beijing 100871 China NELVT National Engineering Laboratory for Video Technology School of Electronics Engineering and Computer Science and Cooperative Medianet Innovation Center Peking University Beijing 100871 China

Image Quality Assessment （IQA） is a fundamental problem in image processing. It is a common principle that human vision is hierarchical： we first perceive global structural information such as contours then focus on local regional details if necessary. Following this principle, we propose a novel framework for IQA by quantifying the degenerations of structural information and region content separately, and mapping both to obtain the objective score. The structural information can be obtained as contours by contour detec- tion techniques. Experiments are conducted to demonstrate its performance in comparison with multiple state-of-the-art methods on two large scale datasets.

关键词： Image quality assessment Contour detection Image segmentation.

Development of a filtered drag model considering effect of the solid shear rate

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Particuology 2022年第12期71卷 63-74页

作者： Lingxue Wang ming jiang Qiang Zhou School of Chemical Engineering and Technology Xi'an Jiaotong UniversityXi'an710049China Engineering Research Center of New Energy System Engineering and Equipment University of Shaanxi ProvinceXi'an710049China State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong UniversityXi'an710049China

This study investigates a 2D gas-solid fast fluidized bed of typical Geldart A particles using highly resolved simulations with two-fluid *** results show that the solid shear rate has a considerable impact on the orientation of the meso-scale structures and hence on the filtered drag *** the basis of the correlation for the filtered drag force established in the literature using the traditional markers(such as filtered solid volume fraction,filtered slip velocity and filter scale),a correction correlated with the solid shear rate in the direction of gravity is proposed for better prediction of the filtered drag *** corrected model is shown to produce improved results in posterior tests of flows in different fluidization regimes including bubbling,turbulent and fast fluidization.

关键词： Gas-solid flows Fluidization Two-fluid model Dimensionless solid shear rate Filtered drag force

Unprecedented self-assembly of precise molecular particles

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National Science Review 2016年第1期3卷 3-4页

作者： Lei Zhu ming jiang Department of Macromolecular Science and Engineering Case Western Reserve University Department of Macromolecular Science and The State Key Laboratory of Molecular Engineering of Polymers Fudan University

Atomic self-assembly in pure metals and metal alloys can lead into various conventional(cubic,hexagonal closepacked(hcp),and icosahedron)and non-conventional(Frank–Kasper and quasicrystal[1])*** nonconventional cryst... 详细信息

关键词： Unprecedented self-assembly of precise molecular particles

Investigation of Susceptibility to Intergranular Corrosion of Tin-Added Austenitic Stainless Steel

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Acta Metallurgica Sinica(English Letters) 2015年第9期28卷 1183-1189页

作者： Min Sun Yuan-Yuan Yang ming Luo Lai-Zhu jiang Yi-ming jiang Jin Li Department of Materials Science Fudan University Research and Development Center Baosteel Co. Ltd.

The intergranular corrosion （IGC） character of tin-added B316LX and the influence of tin addition on IGC susceptibility were investigated by DL-EPR, oxalic acid etch test and transmission electron microscopy. IGC susceptibility of B316LX is mainly caused by the precipitation of M23C6 carbide and intermetallic Laves phase. DL-EPR test is unsuitable to evaluate the IGC susceptibility of B316LX with long-time sensitization, because more carbides and inter- metallic phases are formed at grain boundaries and inside the grains, which induce more severe IGC and pits attacks. Tin addition increases the IGC susceptibility, maybe due to diffusion of tin toward grain boundaries.

关键词： Stainless steel Tin SEM TEM Intergranular corrosion

Landweber Iterative Methods for Angle-limited Image Reconstruction

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Acta Mathematicae Applicatae Sinica 2009年第2期25卷 327-334页

作者： Gang-rong Qu ming jiang School of Science Beijing Jiaotong University Beijing 100044 China LMAM School of Mathematical Sciences Peking University Beijing 100871 China

We introduce a general iterative scheme for angle-limited image reconstruction based on Landwebet＇s method. We derive a representation formula for this scheme and consequently establish its convergence conditions. Our results suggest certain relaxation strategies for an accelerated convergence for angle-limited image reconstruction in L^2-norm comparing with alternative projection methods. The convolution-backprojection algorithm is given for this iterative process.

关键词： The Landweber iteration angle-limited image reconstruction the selections of relaxation coefficients convolution-backprojection algorithm

Effects of Sequence Distribution and Physical Aging on Physical Properties of PES/PEES Random, Block, and Alternative Copolymers

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Chemical Research in Chinese Universities 2006年第6期22卷 787-791页

作者： ZHOU Xiao-ming jiang Zhen-hua Alan G. MacDiarmid Lab College of Chemistry Jilin University Changchun 130012 P. R. China

The random, block, and alternative copolymers of poly ether sulfone（PES） and poly ether ether sulfone（PEES） were synthesized v/a three kinds of methods. The chemical structures of the three kinds of copolymers were characterized by ^13C NMR. Three kinds of PES/PEES copolymers（ Tg =215 ℃ ）, which were almost identical in composition but different in sequence distribution, were used. Their physical aging process was studied by differential scanning calorimetry（DSC） at three aging temperatures ranging between Tg -15 ℃ and Tg -25℃. The experimental results reveal that the alternative copolymer shows a lower enthalpy relaxation time 〈T〉 and apparent activation energy when compared with the random and block copolymers. The result of the electron-microscopy investigation of the three copolymers that were treated at 200 ℃ for 96 h indicates that the molecular aggregation of the copolymers changed from a randomly coiled amorphous phase to an ordered phase, and the ordered structure of the alternative copolymer was more distinct than that of the random phase. The experimental results of this study suggest that the motion of the sagments is affected by the different molecular-chain sequence distribution.

关键词： Physical aging Apparent activation energy Sequence distribution

Simulation Study on Purification Efficiency for Nitrogen in Different Types of Wetlands in Sanjiang Plain, China

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Chinese Geographical Science 2010年第3期20卷 252-257页

作者： GUO Yue jiang ming LU Xianguo Northeast Institute of Geography and Agroecology Chinese Academy of Sciences Changchun 130012 China Graduate University of the Chinese Academy of Sciences Beijing 100049 China

The purification law of nitrogen in Deyeuxia angustifolia, Carex lasiocarpa and Deyeuxia angustifolia-Carex lasiocarpa combined wetland systems in the Sanjiang Plain, China was studied by field simulation experiment. The results indicate that the removal rates of TN, NH4^＋-N and NO3^--N in above three types of wetlands present an obvious logarithm growth trend along with the time. There are evident removal effects for NH4＋-N and NOa--N in water bodies of wetlands after the 30th day of experiment, with the removal rates over 80.0%, but the removal rate of TN is slightly low, being 63.1%-74.3%. NO3 -N is most quickly removed by the combined wetland, and NH4^＋-N by Deyeuxia angustifolia wetland. The removal speeds of TN by the three wetland systems are comparatively slow, of which the Deyeuxia angustifolia wetland is the fastest. In consideration of plant growth season, Deyeuxia angustifolia wetland has much more practical application value in purifying nitrogen. These results can provide references for the study on the purification function of wetlands and the control of non-point source pollution in Northeast China.

关键词： wetland Deyeuxia angustifolia Carex lasiocarpa nitrogen removal rate Sanjiang plain

An iterative BiGAMP-based receiver for coded massive MIMO systems with low-resolution ADCs

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Science China(Information Sciences) 2021年第11期64卷 247-248页

作者： Yi SUN ming jiang Chunming ZHAO National Mobile Communications Research Laboratory Southeast University Purple Mountain Laboratories

Dear editor,The hundreds of antennas deployed in massive multipleinput-multiple-output(MIMO) systems lead to an insupportable burden in terms of hardware costs and power consumption. This has motivated the research on... 详细信息

关键词： Information Systems and Communication Service