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CONDITIONAL EXPECTATIONS AND MARTINGALES IN NONCOMMUTATIVE Lp-SPACES ASSOCIATED WITH CENTER-VALUED TRACES
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作者 Inomjon GANIEV Farrukh MUKHAMEDO V 《Acta Mathematica Scientia》 SCIE CSCD 2017年第4期1019-1032,共14页
In this paper we prove the existence of conditional expectations in the noncom- mutative Lp(M, Ф)-spaces associated with center-valued traces. Moreover, their description is also provided. As an application of the ... In this paper we prove the existence of conditional expectations in the noncom- mutative Lp(M, Ф)-spaces associated with center-valued traces. Moreover, their description is also provided. As an application of the obtained results, we establish the norm convergence of weighted averages of martingales in noncommutative Lp(M, Ф)-spaces. 展开更多
关键词 noncommutative Lp (M Ф)-space Banach-Kantorovich space measurable con-ditional expectation measurable bundle MARTINGALE
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Dependence of the Accuracy of Precipitation and Cloud Simulation on Temporal and Spatial Scales 被引量:2
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作者 高守亭 Xiaofan LI 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2009年第6期1108-1114,共7页
Precipitation and associated cloud hydrometeors have large temporal and spatial variability, which makes accurate quantitative precipitation forecasting difficult. Thus, dependence of accurate precipitation and associ... Precipitation and associated cloud hydrometeors have large temporal and spatial variability, which makes accurate quantitative precipitation forecasting difficult. Thus, dependence of accurate precipitation and associated cloud simulation on temporal and spatial scales becomes an important issue. We report a cloud- resolving modeling analysis on this issue by comparing the control experiment with experiments perturbed by initial temperature, water vapor, and cloud conditions. The simulation is considered to be accurate only if the root-mean-squared difference between the perturbation experiments and the control experiment is smaller than the standard deviation. The analysis may suggest that accurate precipitation and cloud simulations cannot be obtained on both fine temporal and spatial scales simultaneously, which limits quanti- tative precipitation forecasting. The accurate simulation of water vapor convergence could lead to accurate precipitation and cloud simulations on daily time scales, but it may not be beneficial to precipitation and cloud simulations on hourly time scales due to the dominance of cloud processes. 展开更多
关键词 temporal and spatial scales cloud and rainfall simulations cloud-resolving model initial con-ditions
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LOWER BOUNDS OF DIRICHLET EIGENVALUES FOR A CLASS OF FINITELY DEGENERATE GRUSHIN TYPE ELLIPTIC OPERATORS 被引量:2
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作者 陈化 陈洪葛 +1 位作者 段忆芮 胡鑫 《Acta Mathematica Scientia》 SCIE CSCD 2017年第6期1653-1664,共12页
Let Ω be a bounded open domain in Rn with smooth boundary Ω, X =(X1,X2,... ,Xm) be a system of real smooth vector fields defined on Ω and the bound-ary Ω is non-characteristic for X. If X satisfies the HSrmande... Let Ω be a bounded open domain in Rn with smooth boundary Ω, X =(X1,X2,... ,Xm) be a system of real smooth vector fields defined on Ω and the bound-ary Ω is non-characteristic for X. If X satisfies the HSrmander's condition, then the vectorfield is finitely degenerate and the sum of square operator △X =m∑j=1 X2 j is a finitely de-generate elliptic operator. In this paper, we shall study the sharp estimate of the Dirichlet eigenvalue for a class of general Grushin type degenerate elliptic operators △x on Ω. 展开更多
关键词 Dirichlet eigenvalues finitely degenerate elliptic operators HSrmander's con-dition sub-elliptic estimate Grushin type operator
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Dynamics of fundamental and double-pole breathers and solitons for a nonlinear Schrodinger equation with sextic operator under non-zero boundary conditions
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作者 Luyao Zhang Xiyang Xie 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第9期268-280,共13页
We study the dynamics of fundamental and double-pole breathers and solitons for the focusing and defocusing nonlinear Schrodinger equation with the sextic operator under non-zero boundary conditions. Our analysis main... We study the dynamics of fundamental and double-pole breathers and solitons for the focusing and defocusing nonlinear Schrodinger equation with the sextic operator under non-zero boundary conditions. Our analysis mainly focuses onthe dynamical properties of simple- and double-pole solutions. Firstly, through verification, we find that solutions undernon-zero boundary conditions can be transformed into solutions under zero boundary conditions, whether in simple-pole ordouble-pole cases. For the focusing case, in the investigation of simple-pole solutions, temporal periodic breather and thespatial-temporal periodic breather are obtained by modulating parameters. Additionally, in the case of multi-pole solitons,we analyze parallel-state solitons, bound-state solitons, and intersecting solitons, providing a brief analysis of their interactions.In the double-pole case, we observe that the two solitons undergo two interactions, resulting in a distinctive “triangle”crest. Furthermore, for the defocusing case, we briefly consider two situations of simple-pole solutions, obtaining one andtwo dark solitons. 展开更多
关键词 double-pole solitons double-pole breathers Riemann-Hilbert problem non-zero boundary con-ditions nonlinear Schrodinger equation with sextic operator
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Concentration of Heavy Metals in Sediment and Seagrasses Tissue of the Red Sea Coastal Water of the Sudan
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作者 Abdelmoneim Karamalla Gaiballa 《Open Journal of Marine Science》 2023年第4期67-76,共10页
The study investigated the concentration of Lead, Cadmium, Nickels and Chromium in sediment and seagrass tissues at six selected sites along the Sudanese Red Sea coast. The findings of the study added some important a... The study investigated the concentration of Lead, Cadmium, Nickels and Chromium in sediment and seagrass tissues at six selected sites along the Sudanese Red Sea coast. The findings of the study added some important and necessary information about the status and condition of the coastal environment in the Sudanese Red Sea coast in terms of the extent of pollution with heavy metals. The study sites included: Marsa Bashayer, Marsa Dama Dama, Green Area, Shipyard, Marsa Halout and Dungonab Bay. The Atomic Absorption Spectrophotometer was used to measure Lead, Cadmium and Nickels. The colorimetric detection method was used for Chromium using the Spectrophotometer. Marsa Dama Dama site revealed high levels concentration of heavy metals in sediment for Lead (60.5) μg/g, Cadmium (0.22) μg/g and Chromium (146.65) μg/g. Marsa Halout showed the highest mean concentration of Nickel in sediment at 14 μg/g. The variation of concentration of metals in sediment between the sites was not significant. The mean concentration of metals in seagrass species tissues ranged from 3.9 to 26.25 μg/g for Lead, 0.1 to 0.90 μg/g for Cadmium, 0.38 to 5.96 μg/g for Nickel and 0.15 to 0.495 μg/g for Chromium. The differences of concentration of heavy metals in seagrass tissues among the sites were significant for Lead and not significant for Cadmium;Nickel and Chromium. 展开更多
关键词 Heavy Metals SEDIMENT SEAGRASS CONTAMINATION Coastal Environment con-dition
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Optimality conditions for sparse nonlinear programming 被引量:8
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作者 PAN LiLi XIU NaiHua FAN Jun 《Science China Mathematics》 SCIE CSCD 2017年第5期759-776,共18页
The sparse nonlinear programming (SNP) is to minimize a general continuously differentiable func- tion subject to sparsity, nonlinear equality and inequality constraints. We first define two restricted constraint qu... The sparse nonlinear programming (SNP) is to minimize a general continuously differentiable func- tion subject to sparsity, nonlinear equality and inequality constraints. We first define two restricted constraint qualifications and show how these constraint qualifications can be applied to obtain the decomposition properties of the Frechet, Mordukhovich and Clarke normal cones to the sparsity constrained feasible set. Based on the decomposition properties of the normal cones, we then present and analyze three classes of Karush-Kuhn- Tucker (KKT) conditions for the SNP. At last, we establish the second-order necessary optimality condition and sufficient optimality condition for the SNP. 展开更多
关键词 sparse nonlinear programming constraint qualification normal cone first-order optimality con-dition second-order optimality condition
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Weighted Oscillation and Variation Inequalities for Singular Integrals and Commutators Satisfying Hrmander Type Conditions 被引量:1
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作者 Jing ZHANG Huo Xiong WU 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2017年第10期1397-1420,共24页
This paper is devoted to investigating the weighted LP-mapping properties of oscillation and variation operators related to the families of singular integrals and their commutators in higher dimension. We establish th... This paper is devoted to investigating the weighted LP-mapping properties of oscillation and variation operators related to the families of singular integrals and their commutators in higher dimension. We establish the weighted type (p, p) estimates for 1 〈 p 〈 ∞ and the weighted weak type (1, 1) estimate for the oscillation and variation operators of singular integrals with kernels satisfying certain HSrmander type conditions, which contain the Riesz transforms, singular integrals with more general homogeneous kernels satisfying the Lipschitz conditions and the classical Dini's conditions as model examples. Meanwhile, we also obtain the weighted LP-boundeness for such operators associated to the family of commutators generated by the singular integrals above with BMO(Rd)-functions. 展开更多
关键词 OSCILLATION VARIATION singular integrals COMMUTATORS BMO functions HSrmander con-ditions Muckenhoupt weights
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ARTIFICIAL BOUNDARY CONDITIONS FOR "VORTEX IN CELL" METHOD
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作者 LijuanDing ZhenhuanTeng 《Journal of Computational Mathematics》 SCIE EI CSCD 2003年第1期5-14,共10页
This paper mainly designs artificial boundary conditions for 'vortex in cell' method in solving two-dimensional incompressible inviscid fluid under two conditions: one is with periodical initial value in one d... This paper mainly designs artificial boundary conditions for 'vortex in cell' method in solving two-dimensional incompressible inviscid fluid under two conditions: one is with periodical initial value in one direction and the other with compact supported initial value. To mimic the vortex motion, Euler equation is transformed into vorticity-stream function and the technique of vortex in cell is applied incorporating with the artificial boundary conditions. 展开更多
关键词 Incompressible inviscid flow Vortex in cell method Artificial boundary con-dition
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