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The best quadrature based on given Hermite information for the Sobolev class KW^r[a,b]

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Science china mathematics 2006年第8期49卷 1146-1152页

作者： WANG Xinghua & YANG Shijun Department of mathematics, Zhejiang university, Hangzhou 310028, china Department of mathematics, Hangzhou Normal college, Hangzhou 310036, china Department of mathematics Zhejiang University Hangzhou China Department of mathematics Hangzhou Normal College Hangzhou China

As usual, denote by KWr[a,b] the Sobolev class consisting of every function whose (r-1)th derivative is absolutely continuous on the interval [a,b] and rth derivative is bounded by K a.e. In [a,b]. For a function f ∈ KWr[a,b], its values and derivatives up to r-1 order at a set of nodes x are known. These values are said to be the given Hermite *** work reports the results on the best quadrature based on the given Hermite information for the class KWr[a,b]. Existence and concrete construction issue of the best quadrature are settled down by a perfect spline interpolation. It turns out that the best quadrature depends on a system of algebraic equations satisfied by a set of free nodes of the interpolation perfect spline. From our another new result, it is shown that the system can be converted in a closed form to two single-variable polynomial equations, each being of degree approximately r/2. As a by-product,the best interpolation formula for the class KWr[a,b] is also obtained.

关键词： Sobolev class, Hermite information, perfect spline, optimal recovery, best quadrature.

Series-based approximate approach of optimal tracking control for nonlinear systems with time-delay

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Progress in Natural Science:Materials International 2008年第12期18卷 1571-1576页

作者： Gongyou Tang~a Mingqu Fan~(a,b) a college of information Science and Engineering,Ocean university of china,Qingdao 266100,china b college of information and Engineering,Shandong university of Science and Technology,Jinan 250031,china college of information Science and Engineering Ocean University of China Qingdao 266100 China college of information and Engineering Shandong University of Science and Technology Jinan 250031 China

The optimal output tracking control (OTC) problem for nonlinear systems with time-delay is *** a series-based approx- imate approach,the original OTC problem is transformed into iteration solving linear two-point boundary value problems without time- *** OTC law obtained consists of analytical linear feedback and feedforward terms and a nonlinear compensation term with an infinite series of the adjoint *** truncating a finite sum of the adjoint vector series,an approximate optimal tracking control law is obtained.A reduced-order reference input observer is constructed to make the feedforward term physically *** exam- ples are used to test the validity of the series-based approximate approach.

关键词： Nonlinear systems Time-delay Tracking control Optimal control Observer

Weighted norm inequalities for the multilinear Calderón-Zygmund operators

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Science china mathematics 2010年第7期53卷 1859-1872页

作者： HU GuoEn Department of Applied mathematics, Zhengzhou information sciences and Technology Institute,Zhengzhou 450002, china Department of Applied mathematics Zhengzhou Information Sciences and Technology Institute Zhengzhou China

In this paper, by proving some suitable weighted endpoint estimates, and then by multilinear interpolation and a new multilinear extrapolation lemma, the author establishes some weighted estimates for the multilinear ... 详细信息

关键词： multilinear Calderón-Zygmund operator commutator weighted norm inequality interpolation extrapolation

A computational investigation of boron-doped chromium and chromium clusters by density functional theory

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Science china(Physics,Mechanics & Astronomy) 2010年第5期53卷 812-817页

作者： GE GuiXian1,JING Qun1 & LUO YouHua2,3 1 Key Laboratory of Ecophysics and Department of Physics,Normal college,Shihezi university,Xinjiang 832003,china 2 School of Science,East china university of Science and Technology,Shanghai 200237,china 3 Institute of Theoretical Physics,School of Physics and information Optoelectronics,henan university,kaifeng 475004,china Key Laboratory of Ecophysics and Department of Physics Normal College Shihezi University Xinjiang China School of Science East China University of Science and Technology Shanghai China Institute of Theoretical Physics School of Physics and Information Optoelectronics Henan University Kaifeng China

The geometries,stabilities and electronic properties of Crn and CrnB(n=2-9) clusters have been systematically investigated by density functional *** results suggest that the lowest energy structures for CrnB clusters can be obtained by substituting one Cr atom in Crn+1 clusters with B *** geometries of CrnB clusters are similar to that of Crn+1 clusters except for local structural *** second-order difference and fragmentation energy show Cr4,Cr6,Cr8,Cr3B,Cr5B and Cr8B cluster are the most stable among these studied *** impurity B increases the stabilities of chromium *** B is doped on the Crn clusters,cluster geometry does dominate positive role in enhancing their *** doped B atom does not change the coupling way of the Cr site in Crn clusters,but breaks the symmetry and the Cr atoms are no longer *** doped B atom increases the total magnetic moments of Crn in most cases.

关键词： Crn and CrnB clusters geometries electronic properties

Study on north boundary of subtropical zone in Funiu Mountain according to soil geochemistry

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Journal of Geographical sciences 2003年第3期13卷 299-304页

作者： MA Jianhua,XU Shuming,HAN Jinxian,ZHU Lianqi,ZHAO Qingliang(college of Environment and Planning, henan university, kaifeng 475001, china) college of Environment and Planning Henan University Kaifeng 475001

The boundary between subtropical zone and temperate zone is not only important in physical geography, but also attractive in agricultural production. Seven soil profiles studied in this paper are placed along the southern slope of Funiu Mountain at different heights above sea level. Many compositions and properties of these soils have been determined in laboratory. In this paper, the laws of migration and accumulation of soil materials on the southern slope of Funiu Mountain are discussed first, then the division of the boundary between subtropical zone and temperate zone in this area according to soil geochemistry is discussed with qualitative methods and mathematical classification method in which twelve selected indexes such as K m , Saf, Ba, β, Feo/Fet, Mno/Mnt and so on are used. The result indicates that the boundary between subtropical zone and temperate zone on the southern slope of Funiu Mountain is about 950 m above sea level.

关键词： Funiu Mountain subtropical zone migration and accumulation of soil materials

Heart failure in china:epidemiology and current management

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Journal of Geriatric Cardiology 2024年第6期21卷 631-641页

作者： Sheng-Shou HU the Writing Committee of the Report on Cardiovascular Health and Diseases in china Fuwai Hospital National Center for Cardiovascular DiseasesChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina

The Annual Report on Cardiovascular Health and Diseases in china(2022)intricate landscape of cardiovascularhealth in *** connection with the previous section,this sixth section of the report offers a comprehensive analysis of heart failure(HF)in *** is one of the most important cardiovascular disease in the 21st *** mortality is equivalent to that of *** is an important public health problem that seriously affects the health of Chinese *** recent years,with the deepeningof understanding,the change of treatment principles,the innovation of treatment methods and the update of treatment guidelines,the in-hospital mortality of HF patients has declined,and the long-term prognosis is also ***,there are stilldifferences in the management level of HF among different hospitals in *** to improve the standardized diagnosis andtreatment level of HF in china remains an important challenge.

关键词： epidemiology diagnosis treatment

Transition of Growth Mode in Homoepitaxy on Metal Surface

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Communications in Theoretical Physics 2007年第7期48卷 175-178页

作者： WU Li-Li LU Hang-Jun WU Feng-Min college of mathematics and Physics,information Engineering,Zhejiang Normal university,Jinhua 321004,china college of mathematics and Physics Information Engineering Zhejiang Normal University Jinhua 321004 China

The process of the multilayer growth of Pt on Pt(111)is studied by using a Monte Carlo model with realisticphysical *** effects of the substrate temperature,the ES barrier,and the deposition rate on the growthmode have been *** transitions of the surface roughness from oscillatory to non-oscillatory behaviorand then back to oscillatory behavior are observed while increasing the substrate temperature from 270 K to 620 *** found that the growth mode depends strongly on ES barrier over the whole temperatures and the deposition rate ofatoms effectively affects the growth *** simulation results are consistent with many experimental observationsfor homoexpitaxy on a Pt(111)substrate.

关键词： growth mode transition Monte Carlo simulation surface roughness oscillation

Continued Fraction Algorithm for Matrix Exponentials

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Journal of Shanghai university(English Edition) 2001年第1期5卷 11-14页

作者： GU Chuan qing Department of mathematics, college of sciences, Shanghai university, Shanghai 200436, china Department of mathematics College of Sciences Shanghai University Shanghai China

A recursive rational algorithm for matrix exponentials was obtained by making use of the generalized inverse of a matrix in this paper. On the basis of the n th convergence of Thiele type continued fraction expansion, a new type of the generalized inverse matrix valued Padé approximant (GMPA) for matrix exponentials was defined and its remainder formula was proved. The results of this paper were illustrated by some examples.

关键词： matrix exponentials generalized inverse continued fraction algorithm Padé approximant

Piecewise-Koszul algebras

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Science china mathematics 2007年第12期50卷 1795-1804页

作者： Jia-feng L■~1 Ji-wei HE~2 Di-ming LU~(1+) ~1 Department of mathematics,Zhejiang university,Hangzhou 310027,china ~2 Department of mathematics,Shaoxing college of Arts and sciences,Shaoxing 312000,china Department of mathematics Zhejiang University Hangzhou China Department of mathematics Shaoxing College of Arts and Sciences Shaoxing China

It is a small step toward the Koszul-type *** piecewise-Koszul algebras are, in general,a new class of quadratic algebras but not the classical Koszul ones,simultaneously they agree with both the classical Koszul and higher Koszul algebras in special *** give a criteria theorem for a graded algebra A to be piecewise-Koszul in terms of its Yoneda-Ext algebra E(A),and show an A_∞-structure on E(A).Relations between Koszul algebras and piecewise-Koszul algebras are *** particular,our results are related to the third question of Green-Marcos.

关键词： (d-)Koszul algebras A_∞-algebras Yoneda-Ext algebras