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The Testing Strength Curves of Lightweight Aggregate Concrete by Rebound Method and Ultrasonic-rebound Combined Method

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Journal of Wuhan university of Technology(Materials {1.) 2011年第5期26卷 1010-1017页

作者：荣辉 school of Materials {1. and Engineering Southeast University

The strength curves of lightweight aggregate concrete （LWAC） were tested based on detecting LWAC with density of 1.400-1.900 kg/m3 and LWAC with strength grade of LC1.-LC50 by rebound method and ultrasonic-rebound combined *** results show that the common measured strength curves tested by above two methods can not satisfy the required accuracy of LWAC strength *** addition,specified compressive strength curves of testing LWAC by rebound method and ultrasonic-rebound combined method are obtained,respectively.

关键词： lightweight aggregate concrete compressive strength rebound method testing-strength curve ultrasonic-rebound combined method

以“千万工程”为指引打造“青农飞地”引育新农人助力乡村振兴

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中国共青团 2024年第7期 62-65页

作者： 1.团金华市委 2.团婺城区委团金华市委团婺城区委

习近平总书记在义乌李祖村考察调研时指出“乡村振兴为年轻人提供了展现才华的用武之地,希望更多的年轻人为乡村振兴发挥积极作用”。为深入学习贯彻习近平总书记关于实施乡村振兴战略的重要论述,共青团金华市委以“千万工程”为指引,... 详细信息

习近平总书记在义乌李祖村考察调研时指出“乡村振兴为年轻人提供了展现才华的用武之地,希望更多的年轻人为乡村振兴发挥积极作用”。为深入学习贯彻习近平总书记关于实施乡村振兴战略的重要论述,共青团金华市委以“千万工程”为指引,着力破解青年投身农创“不愿回、留不下、干不好”三个痛点、难点问题,率先在婺城区探索建设“青农飞地”省级共富试点,旨在建立政府主导、多方协同、市场化运作的青年农创枢纽平台,推动城乡之间各类创业资源和要素高效流通。

关键词：乡村振兴创业资源共富婺城区新农人飞地多方协同市场化运作

On conformal measures for infinitely renormalizable quadratic polynomials

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science China {1. 2005年第10期48卷 1411-1420页

作者： HUANG Zhiyong~1.JIANG Yunping~(2,3) & WANG Yuefei~3 1. school of Information,Renmin {1. of China,Beijing 1.0872,China 2. Department of mathematics,Queens College,City {1. of New York,NY 1.367,USA Department of mathematics,Graduate school,City {1. of New York,New York,NY 1.01.,USA 3. Academy of mathematics and Systems science,Chinese Academy of sciences,Beijing 1.0080,China 1. school of Information Renmin University of China 100872 Beijing China 2. Department of mathematics Queens College City University of New York 11367 NY USA 3. Department of mathematics Graduate School City University of New York 10016 New York NY USA 4. Academy of mathematics and Systems {1. Chinese Academy of Sciences 100080 Beijing China

We study a conformal measure for an infinitely renormalizable quadratic polynomial. We prove that the conformal measure is ergodic if the polynomial is unbranched and has complex bounds. The main technique we use in t... 详细信息

关键词： Julia set, conformal measure, three-dimensional puzzle, infinitely renormalizable quadratic polynomial.

Minimal symmetric submanifolds in compact Riemannian symmetric spaces

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Chinese science Bulletin 1998年第21期43卷 1786-1789页

作者： LIANG Ke 1.and JIN Quanqin 1.2 1. Department of mathematics, Nankai {1., Tianjin 300071. China 2. Department of mathematics, Hebei {1., Baoding 071.02, China Department of mathematics Nankai University Tianjin China Department of mathematics Hebei University Baoding China

A necessary and sufficient condition for a symmetric submanifold to be minimal in its ambient compact Riemannian symmetric space is given. By this condition a complete classification of non- minimal symmetric submanif... 详细信息

关键词： symmetric space symmetric submanifold mean curvature vector.

MAXIMUM PRINCIPLE FOR FORWARD-BACKWARD STOCHASTIC CONTROL SYSTEM WITH RANDOM JUMPS AND APPLICATIONS TO FINANCE

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Journal of Systems science & Complexity 2010年第2期23卷 219-231页

作者： Jingtao SHI·Zhen WU school of {1.,shandong university,Jinan 2501.0,China. school of {1. Shandong University

Both necessary and sufficient maximum principles for optimal control of stochastic systemwith random jumps consisting of forward and backward state variables are *** control variableis allowed to enter both diffusion and jump *** result is applied to a mean-varianceportfolio selection mixed with a recursive utility functional optimization *** expressionof the optimal portfolio selection strategy is obtained in the state feedback form.

关键词： Forward-backward stochastic control system maximum principle Poisson random measure recursive utility stochastic optimal control.

Finite groups in which elements of the same order outside the center are conjugate

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science China {1. 2007年第10期50卷 1493-1500页

作者： Xing-zhong YOU~1.Guo-hua QIAN~2 Wu-jie SHI~(3+) ~1.school of {1. and Computing science,Changsha university of science and Technology,Changsha 41.076,China ~2 Department of {1.,Changshu Institute of Technology,Changshu 21.500,China ~3 school of {1.,Suzhou university,Suzhou 21.006,China 1. school of {1. and Computing science Changsha University of Science and Technology Changsha 410076 China 2. Department of mathematics Changshu Institute of Technology Changshu 215500 China 3. school of {1. Suzhou University Suzhou 215006 China

We prove that if G is a finite group in which the elements of the same order outside the center are conjugate, then either G is abelian or G ≌ S3.

关键词： finite group, rational group, conjugacy class

A study of two-dimensional magnetic polaron

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science China(Physics,Mechanics & Astronomy) 2006年第4期49卷 421-429页

作者： LIU Tao1. ZHANG Huaihong1. FENG Mang1.2 & WANG Kelin1.3 1. school of {1., Southwest university of {1. and Technology, Mianyang 621.1., China 2. Wuhan Institute of Physics and mathematics, Chinese Academy of {1.s, Wuhan 430070, China 3. Department of Modern Physics, university of {1. and Technology of China, Hefei 230026, China school of {1. Southwest University of Science Technology Mianyang 621010 China Wuhan Institute of Physics mathematics Chinese Academy of Sciences Wuhan 430070 China Department of Modern Physics University of Science Technology of China Hefei 230026 China

By using the variational method and anneal simulation, we study in this paper the self-trapped magnetic polaron (STMP) in two-dimensional anti-ferromagnetic material and the bound magnetic polaron (BMP) in ferromagnetic material. Schwinger angular momentum theory is applied to changing the problem into a coupling problem of carriers and two types of Bosons. Our calculation shows that there are single-peak and multi-peak structures in the two-dimensional STMP. For the ferromagnetic material, the properties of the two-dimensional BMP are almost the same as that in one-dimensional case; but for the anti-ferromagnetic material, the two-dimensional STMP structure is much richer than the one-dimensional case.

关键词： self-trapped magnetic polaron, bound magnetic polaron, impurity potential, anti-ferromagnet.

Recurrence spectra of He atoms in strong external fields

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science China(Physics,Mechanics & Astronomy) 2004年第4期47卷 477-484页

作者： LIN Shenglu1. LI Hongyun1. WANG Dehua2, ZHAO Wenli1.& GAO Feng1.1. Department of Physics, shandong Normal {1., Jinan 25001., China 2. Department of mathematics and Physics, shandong Institute of Architecture and Engineering, Jinan 25001., China 1. Department of Physics Shandong Normal University 250014 Jinan China 2. Department of mathematics and Physics Shandong Institute of Architecture and Engineering 250014 Jinan China

By employing a model potential including the electron exchange energy, we extend the semiclassical closed orbit theory to study the multielectron atoms. Using special region-splitting consistent and iterative method, we figure out the closed orbits in the corresponding classical system and calculate the recurrence spectra of triplet helium atoms in parallel electric and magnetic fields at scaled energy ε=?0.03,n≈40,n=0. The core-scattering effects have been taken into account, which lead to more peaks in the spectra. It has also been confirmed by means of the direct comparison between the spectral portrait in such a plot and those of hydrogen case. In order to compare the theoretic results with experiment, we investigate the closed orbits and recurrence spectra of helium atoms for the similar exchange potential but applied only by single electric field at scaled energy ε=?2.7 case. The spectra are in good agreement with the experimental observation. We conclude that our model is correct and it is necessary to consider the exchange effect for determining the photoabsorption spectra of multielectron atoms in strong external fields.

关键词： exchange potential, recurrence spectra, semiclassical closed orbit theory, core-scattering.

Howe duality in Dunkl superspace

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science China {1. 2010年第12期53卷 3153-3162页

作者： REN GuangBin 1.2 1.Department of mathematics, {1. of science and Technology of China, Hefei 230026, China 2 Department of mathematics, {1. of Aveiro, Aveiro 381.-1.3, Portugal 1. Department of mathematics University of Science and Technology of China Hefei 230026 China2. Department of Mathematics University of Aveiro Aveiro 3810-193 Portugal

In the framework of superspace in Clifford analysis for the Dunkl version, the Fischer decomposition is established for solutions of the Dunkl super Dirac operators. The result is general without restrictions on multiplicity functions or on super dimensions. The Fischer decomposition provides a module for the Howe dual pair G × osp(1.2) on the space of spinor valued polynomials with G the Coxeter group, while the generators of the Lie superspace reveal the naturality of the Fischer decomposition.

关键词： Dunkl operators superspace Fischer decomposition Dirac operator