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EXPONENTIAL CONVERGENCE OF SAMPLE AVERAGE APPROXIMATION METHODS FOR A CLASS OF STOCHASTIC MATHEMATICAL PROGRAMS WITH COMPLEMENTARITY CONSTRAINTS

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Journal of Computational Mathematics 2006年第6期24卷 733-748页

作者： Fan-wen Meng hui-fu Xu The Logistics Institute - Asia Pacific National University of Singapore 1 Law Link Singapore School of Mathematics University of Southampton Highfield Southampton S017 1B J UK School of Mathematics University of Southampton Highfield Southampton S017 1B J UK

In this paper, we propose a Sample Average Approximation （SAA） method for a class of Stochastic Mathematical Programs with Complementarity Constraints （SMPCC） recently considered by Birbil, G/irkan and Listes [3]. We study the statistical properties of obtained SAA estimators. In particular we show that under moderate conditions a sequence of weak stationary points of SAA programs converge to a weak stationary point of the true problem with probability approaching one at exponential rate as the sample size tends to infinity. To implement the SAA method more efficiently, we incorporate the method with some techniques such as Scholtes＇ regularization method and the well known smoothing NCP method. Some preliminary numerical results are reported.

关键词： Stochastic mathematical programs with complementarity constraints Sampleaverage approximation Weak stationary points Exponential convergence.

Uniqueness to Some Inverse Source Problems for the Wave Equation in Unbounded Domains

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Acta Mathematicae Applicatae Sinica 2020年第1期36卷 134-150页

作者： Guang-hui HU Yavar KIAN yue ZHAO Beijing Computational Science Research Center Beijing 100193China Aix Marseille Univ Universit’e de ToulonCNRSCPTMarseilleFrance School of Mathematics and Statistics Central China Normal UniversityWuhan 430079China

This paper is concerned with inverse acoustic source problems in an unbounded domain with dynamical boundary surface data of Dirichlet *** measurement data are taken at a surface far away from the source *** prove uniqueness in recovering source terms of the form f(x)g(t)and f(x1,x2,t)h(x3),where g(t)and h(x3)are given and x=(x1,x2,x3)is the spatial variable in three *** these a priori information,we prove that the boundary data of a family of solutions can be used to recover general source terms depending on both time and spatial *** moving point sources radiating periodic signals,the data recorded at four receivers are prove sufficient to uniquely recover the orbit *** determination of embedded obstacles and source terms was verified in an inhomogeneous background medium using the observation data of infinite time *** approach depends heavily on the Laplace transform.

关键词： Inverse source problems Laplace transform moving point source uniqueness

Nearly Uniform Design Construction on Flexible Region

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Acta Mathematicae Applicatae Sinica 2020年第3期36卷 557-565页

作者： Jian-hui NING wen-wen YIN Li PENG School of Mathematics and Statistics Center China Normal UniversityWuhan 430079China School of statistics Renmin University of ChinaBeijing 100872China Department of Statistics General Administration of Customs of the People's Republic of ChinaBeijing 100730China

In this paper,we deduced an iteration formula for the computation of central composite *** using the iteration formula,the computational complexity of uniform design construction in flexible region can be greatly *** we also made a refinement to threshold accepting algorithm to accelerate the algorithm's convergence *** show that the refined algorithm can converge to the lower discrepancy design more stably.

关键词： uniform design flexible region central composite discrepancy threshold accepting algorithm

One-year results for myopia control of orthokeratology with different back optic zone diameters: a randomized trial using a novel multispectral-based topographer

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International Journal of Ophthalmology(English edition) 2024年第2期17卷 324-330页

作者： wen-Ting Tang Xiang-Ning Luo wen-Jing Zhao Jia Liao Xin-yue Xu hui-Dan Zhang Li Zhang Department of Ophthalmology the First Affiliated Hospital of Chengdu Medical CollegeChengdu Medical CollegeChengdu 610500Sichuan ProvinceChina

AIM:To present the 1-year results of a prospective cohort study investigating the efficacy,potential mechanism,and safety of orthokeratology(ortho-k)with different back optic zone diameters(BOZD)for myopia control in ***:This randomized clinical study was performed between Dec.2020 and *** were randomly assigned to three groups wearing ortho-k:5 mm BOZD(5-MM group),5.5 mm BOZD(5.5-MM group),and 6 mm BOZD(6-MM group).The 1-year data were recorded,including axial length,relative peripheral refraction(RPR,measured by multispectral refractive topography,MRT),and visual *** contrast sensitivity(CS)was evaluated by CSV-1000 instrument with spatial frequencies of 3,6,12,and 18 cycles/degree(c/d);the corneal higher-order aberrations(HOAs)were measured by iTrace aberration *** one-way ANOVA was performed to assess the differences between the three *** correlation between the change in AL and RPR was calculated by Pearson’s correlation ***:The 1-year results of 20,21,and 21 subjects in the 5-MM,5.5-MM,and 6-MM groups,respectively,were *** were no statistical differences in baseline age,sex,or ocular parameters between the three groups(all P>0.05).At the 1-year visit,the 5-MM group had lower axial elongation than the 6-MM group(0.07±0.09 vs 0.18±0.11 mm,P=0.001).The 5-MM group had more myopic total RPR(TRPR,P=0.014),with RPR in the 15°–30°(RPR 15–30,P=0.015),30°–45°(RPR 30–45,P=0.011),temporal(RPR-T,P=0.008),and nasal area(RPR-N,P<0.001)than the 6-MM *** 15–30 in the 5.5-MM group was more myopic than that in the 6-MM group(P=0.002),and RPR-N in the 5-MM group was more myopic than that in the 5.5-MM group(P<0.001).There were positive correlations between the axial elongation and the change in TRPR(r=0.756,P<0.001),RPR 15–30(r=0.364,P=0.004),RPR 30–45(r=0.306,P=0.016),and RPR-N(r=0.253,P=0.047).The CS decreased at 3 c/d(P<0.001),and the corneal HOAs increased in the 5-MM group(P=0.030).CONCL

关键词： relative peripheral refraction orthokeratology myopia back optic zone diameter axial length multispectral refractive topography

Properties and effect of forming sewage sludge into lightweight ceramics

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Frontiers of Environmental Science & Engineering 2012年第1期6卷 117-124页

作者： Min yue Qinyan yue Yuanfeng QI Baoyu GAO hui YU Shandong Provincial Key Laboratory of Water Pollution Control and Resource Reuse School of Environmental Science and EngineeringShandong UniversityJinan 250100China

In this work we investigated the chemical, thermal and toxic properties of dried sewage sludge （DSS）, the preparation and properties of lightweight sludge ceramic （LSC） and the mechanisms of action of the organic and inorganic foaming agents （OFAs and IFAs）. The chemical components and thermal properties of the raw materials were studied by Energy Dispersive X-ray Detection （EDX） and Thermogravimetric Analysis and Differential Scanning Calorimetry （DSC/TGA）. The mineral phases of the raw materials and the formed ceramics were determined by X-ray Diffraction （XRD）. The leaching characteristics of heavy metals were investigated with inductively Coupled Plasma Atomic Emission Spectrometry （ICP-AES）. Different ratios of DSS and clay were mixed and pressed into raw pellets. After drying and preheating treatment, the raw pellets were sintered at 1150℃ for 10 rain. The physical properties of LSC （50 wt% DSS added） were tested. The results showed that when the addition of DSS was above 50 wt%, LSC began to shrink, and a maximum density occurred. The environmental safety of LSC was satisfactory. XRD showed that some new mineral phases formed in the LSC. Observation of the microstructure by Scanning Electron Microscope （SEM） indicated that the body of LSC was porous.

关键词： sludge foaming agents ceramics preheating process

Sulfonated Hollow Covalent Organic Polymer： Highly-Selective Adsorption toward Cationic Organic Dyes over Anionic Ones in Aqueous Solution

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Chinese Journal of Chemistry 2018年第9期36卷 826-830页

作者： Jian-Hong Wang yue Zhang Lian-dai An wen-He Wang Ying-hui Zhang Xian-He Bu College of Chemistry Key Laboratory of Advanced Energy Materials Chemistry (MOE) Nankai University Tianjin 300071 China TEDA Institute of Applied Physics Nankai University Tianjin 300457 China CSchool of Materials Science and Engineering National Institute for Ad- vanced Materials Tianjin Key Laboratory of Metal and Molecule-Based Material Chemistry Nankai University Tianjin 300350 China

A sulfonated hollow covalent organic polymer （sh-COP-P） was prepared by post sulfonation of hollow covalent organic polymer （h-COP-P） synthesized through poly-condensation of tetrabiphenylporphyrin （TBPP）. In comparison with h-COP-P, sh-COP-P exhibits significantly enhanced adsorp- tion capacity of organic cationic dyes in aqueous solutions accompanied with notably reduced adsorption capacity of anionic dyes. This gives sh-COP-P a satisfactory performance in selectively separating cationic organic dyes from anionic ones, mainly attributed to the electrostatic interaction between polymer backbone and the guest molecules.

关键词： dye adsorption sulfonated hollow COPs organic dyes selective separation

Equivalent model of close-packed film cooling holes in nickel-based single crystal cooled blade based on crystallographic theory

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Chinese Journal of Aeronautics 2019年第4期32卷 839-850页

作者： Yamin ZHANG Zhixun wen Haiqing PEI Zhufeng yue School of Mechanics Civil Engineering and ArchitectureNorthwestern Polytechnical University

The mechanical properties of nickel-based single crystal thin-walled plate with close-packed film cooling holes were studied based on the equivalent solid material concept. The effective plastic parameters inversion method based on crystallographic theory were proposed. A simplification method for close-packed film cooling hole plates with square and triangular penetration patterns was presented. A large number of finite element analysis results covering different ligament efficiencies and penetration patterns were provided to verify the feasibility of the plastic equivalent principle and simplification method. The results show that the stress–strain curve and resolved shear stresses of simplification models are in consistence with the plate models with close-packed film cooling holes. The equivalent errors of yield strength are all within the error band and the values of equivalent errors are all less than 10%. In addition, the equivalent errors of the positions where maximum resolved shear stress occurs are all less than 15°, indicating the accuracy of plastic equivalent model and simplification method.

关键词： Close-packed film cooling holes Crystallographic theory Equivalent Simplification Single crystal

Coupling dynamic analysis of spacecraft with multiple cylindrical tanks and flexible appendages

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Acta Mechanica Sinica 2016年第1期32卷 144-155页

作者： wen-Jun Wu Bao-Zeng yue Hua Huang School of Aerospace Engineering Beijing Institute of Technology School of Automobile and Traffic Engineering Guangxi University of Science and Technology Satellite Communication Department China Academy of Space Technology

This paper is mainly concerned with the coupling dynamic analysis of a complex spacecraft consisting of one main rigid platform, multiple liquid-filled cylindrical tanks, and a number of flexible appendages. Firstly, the carrier potential function equations of liquid in the tanks are deduced according to the wall boundary conditions. Through employ- ing the Fourier-Bessel series expansion method, the dynamic boundaries conditions on a curved free-surface under a low-gravity environment are transformed to general simple differential equations and the rigid-liquid coupled sloshing dynamic state equations of liquid in tanks are obtained. The state vectors of rigid-liquid coupled equations are composed with the modal coordinates of the relative potential func- tion and the modal coordinates of wave height. Based on the B ernoulli-Euler beam theory and the D＇Alembert＇s prin- ciple, the rigid-flexible coupled dynamic state equations of flexible appendages are directly derived, and the coordi- nate transform matrixes of maneuvering flexible appendages are precisely computed as time-varying. Then, the cou- pling dynamics state equations of the overall system of the spacecraft are modularly built by means of the Lagrange＇s equations in terms of quasi-coordinates. Lastly, the cou-piing dynamic performances of a typical complex spacecraft are studied. The availability and reliability of the presented method are also confirmed.

关键词： Multiple liquid-filled cylindrical tanks TheFourier-Bessel series expansion method Low-gravityenvironment Maneuvering flexible appendages TheLagrange's equations in terms of quasi-coordinates

EXPERIMENTAL STUDY OF 3-D TURBULENT BEND FLOWS IN OPEN CHANNEL

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Journal of Hydrodynamics 2005年第6期17卷 704-712页

作者： LIU yue-qin ZHENG Shao-wen WU Qiang School of Resource and Safety Engineering China University of Mining and Technology. Beijing 10083China College of Traffic and Communications South China University of Technology Guangzhou 510640 China

A generalized hend flow model, treating a 90° single bend and 60° continuous hends, was designed to quantitatively describe 3-D turhulenee mechanism of circulating notfully-developed flow in open channels with hends. The 3-D fluctuating veloeities of turbulent flow were measured and analyzed with a 3 D acoustic-Doppler velocimeter. Formula for 3 D turbulent intensity was derived using the dimension analysis approaeh. Expressions of vertical turbulent intensity distributions were obtained with the multivariant-rcgression theo ry, whieh agree with experiment data. Distrihutions of turbulent intensity and turbulent stress were characterized, and their relationships were concluded. In the bend-turbulent flow core region, longitudinal and lateral turbulent-intensity distri hutions are coincident with linear distribution, hut in nearwall region are coincident with the Gamma distribution. Verotical turbulent intensity distributions are coincident with the Rayleigh distribution. Herein, it is concluded that the bend turbulence is anisotropic.

关键词： Reynolds stress 3-D turbulent intensity,bend flow channel model