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Journal of Computational Mathematics 2018年第2期36卷 183-201页

作者： Wanfang Shen liang ge School of Mathematic and Quantitative Economics Shandong University of Finance and Economics Jinan Shandong 250014 China School of Mathematical Sciences University of Jinan Jinan Shandong 250022 China

In this paper, we apply stochastic Galerkin finite element methods to the optimal control problem governed by an elliptic integral-differential PDEs with random field. The control problem has the control constraints of obstacle type. A new gradient algorithm based on the pre-conditioner conjugate gradient algorithm （PCG） is developed for this optimal control problem. This algorithm can transform a part of the state equation matrix and co-state equation matrix into block diagonal matrix and then solve the optimal control systems iteratively. The proof of convergence for this algorithm is also discussed. Finally numerical examples of a medial size are presented to illustrate our theoretical results.

关键词： Effective gradient algorithm Stochastic Galerkin method Optimal controlproblem Elliptic integro-differential equations with random coefficients.

A SPARSE GRID STOCHASTIC COLLOCATION AND FINITE VOLUME ELEMENT METHOD FOR CONSTRAINED OPTIMAL CONTROL PROBLEM GOVERNED BY RANDOM ELLIPTIC EQUATIONS

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Journal of Computational Mathematics 2018年第2期36卷 310-330页

作者： liang ge Tongjun Sun School of Mathematical Sciences University of Jinan Jinan Shandong 250022 China School of Mathematics Shandong University Jinan Shandong 250100 China

In this paper, a hybird approximation scheme for an optimal control problem governed by an elliptic equation with random field in its coefficients is considered. The random coefficients are smooth in the physical space and depend on a large number of random variables in the probability space. The necessary and sufficient optimality conditions for the optimal control problem are obtained. The scheme is established to approximate the optimality system through the discretization by using finite volume element method for the spatial space and a sparse grid stochastic collocation method based on the Smolyak approximation for the probability space, respectively. This scheme naturally leads to the discrete solutions of an uncoupled deterministic problem. The existence and uniqueness of the discrete solutions are proved. A priori error estimates are derived for the state, the co-state and the control variables. Numerical examples are presented to illustrate our theoretical results.

关键词： Optimal control problem Random elliptic equations Finite volume element,Sparse grid Smolyak approximation A priori error estimates.

How Does Tropical Cyclone Size Affect the Onset Timing of Secondary Eyewall Formation？

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Journal of Meteorological Research 2018年第1期32卷 124-134页

作者： liang GUAN Xuyang ge Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters/Key Laboratory of Meteorological Disaster Nanjing University of Information Science & Technology Nanjing 210044 Shanghai Meteorological Science and Technology Service Center Shanghai 200030

By using idealized numerical simulations, the impact of tropical cyclone size on secondary eyewall formation（SEF） is examined. Both unbalanced boundary layer and balanced processes are examined to reveal the underlying mechanism. The results show that a tropical cyclone（TC） with a larger initial size favors a quicker SEF and a larger outer eyewall. For a TC with a larger initial size, it will lead to a stronger surface entropy flux, and thus more active outer convection. Meanwhile, a greater inertial stability helps the conversion from diabatic heating to kinetic ***, the progressively broadening of the tangential wind field will induce significant boundary layer imbalances. This unbalanced boundary layer process results in a supergradient wind zone that acts as an important mechanism for triggering and maintaining deep convection. In short, different behaviors of balanced and unbalanced processes associated with the initial wind profile lead to different development rates of the secondary eyewall.

关键词： secondary eyewall formation tropical cyclone size surface entropy flux

Double resonance in star networks of bistable units with disordered signals

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Communications in Theoretical Physics 2020年第5期72卷 98-104页

作者： Yang ge Xiao-Ming liang School of Physics and Electronic Engineering Jiangsu Normal UniversityXuzhou 221116China

It has been found that a hub node is better able to amplify weak external signals than leaf nodes in star *** hub-enhanced amplification is only attained by a single hub node and is limited to weak coupling *** show here that random initial phases in external weak signals do not affect the hub-enhanced amplification at weak coupling ***,they can improve the responses of all the leaf nodes to external signals at large coupling strength,resulting in a double resonance-like signal *** use a reduced model to analyze the influence of the star structure and random initial phases on the emergence of double resonance.

关键词： signal amplification random initial phases star networks bistable units

Non-negative matrix factorization based modeling and training algorithm for multi-label learning

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Frontiers of Computer Science 2019年第6期13卷 1243-1254页

作者： liang SUN Hongwei ge Wenjing KANG College of Computer Science and Technology Dalian University of TechnologyDalian 116024China

Multi-label learning is more complicated than single-label learning since the semantics of the instances are usually overlapped and not *** effectiveness of many algorithms often fails when the correlations in the feature and label space are not fully *** this end,we propose a novel non-negative matrix factorization(NMF)based modeling and training algorithm that learns from both the adjacencies of the instances and the labels of the training *** the modeling process,a set of generators are constructed,and the associations among generators,instances,and labels are set up,with which the label prediction is *** the training process,the parameters involved in the process of modeling are ***,an NMF based algorithm is proposed to determine the associations between generators and instances,and a non-negative least square optimization algorithm is applied to determine the associations between generators and *** proposed algorithm fully takes the advantage of smoothness assumption,so that the labels are properly *** experiments were carried out on six set of *** results demonstrate the effectiveness of the proposed algorithms.

关键词： multi-label learning non-negative least square optimization non-negative matrix factorization smoothness assumption

On Coleman Automorphisms of Finite Nilpotent Groups by Cyclic Groups

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Acta Mathematica Sinica,English Series 2016年第12期32卷 1459-1464页

作者： Jin Ke hai Sheng Bo ge College of Mathematics and Statistics Qingdao University

Let G be a finite group and let N be a nilpotent normal subgroup of G such that G/N is cyclic. It is shown that under some conditions all Coleman automorphisms of G are inner. Interest in such automorphisms arose from... 详细信息

关键词： Coleman automorphism the normalizer property nilpotent group

Reverse modulation of defect density of Ce-MOF-808 by solventassisted ligand exchange for dicyclopentadiene hydrogenation

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Science China Chemistry 2025年

作者： Danfeng Zhao Fajie Hu Rushuo Li Xinmeng Xu Zhaokun Wang Zuoshuai Xi Jun Tong Xiubing Huang ge Wang Advanced Innovation Center for Materials genome Engineering Beijing Key Laboratory of Function Materials for Molecule & Structure Construction School of Materials Science and Engineering University of Science and Technology Beijing

Defect engineering is a pivotal strategy for tailoring the electronic structure and physicochemical properties of catalysts, yet the straightforward manipulation of defect density in porous materials presents a current challenge. In this work, we achieved precise control over the coordination unsaturated site（CUS） content and pore architecture of Ce-MOF-808 by employing 2-fluorobenzoic acid（2-FBA） as a modifier. Leveraging the p Kadisparities among three ligands（1,3,5-tricarboxylic benzoic acid,formic acid, and 2-FBA）, we preserved the spn topology of Ce-MOF within an aqueous system, while realizing partial substitution of the auxiliary ligands and saturation of the CUS. The amount of 2-FBA was negatively correlated with the number of ligand defects, and the consequent decrease in Ce3+content and the increase in the number of ligand linkages also induced crystal structure transformation. The modulation of the defect structure was correlated with the catalytic performance of dicyclopentadiene（DCPD） hydrogenation reaction, in which Ce-MMF0.15, constructed by the modulation of 0.15 mol amount of 2-fluorobenzoic acid, exhibited an optimal ligand defect density and micro-mesoporous structure, enabling almost complete conversion of DCPD at 100 ℃ and 2 MPa. This article also elucidates the correlation between the regulation of defect density and the accessibility of frustrated Lewis pair（FLP） active sites, guiding the application of novel porous intrinsic FLP materials in hydrogenation catalysis.

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Dependence Rayleigh competing risks model with generalized censored data

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Journal of Systems Engineering and Electronics 2020年第4期31卷 852-858页

作者： WANG liang MA Jin’ge SHI Yimin School of Mathematics and Statistics Xi’an Jiaotong UniversityXi’an 710049China School of Mathematics Yunnan Normal UniversityKunming 650500China School of Mathematics and Statistics Xidian UniversityXi’an 710071China Department of Applied Mathematics Northwestern Polytechnical UniversityXi’an 710072China

The inference for the dependent competing risks model is studied and the dependent structure of failure causes is modeled by a Marshall-Olkin bivariate Rayleigh distribution. Under generalized progressive hybrid censoring(GPHC), maximum likelihood estimates are established and the confidence intervals are constructed based on the asymptotic theory. Bayesian estimates and the highest posterior density credible intervals are obtained by using Gibbs sampling. Simulation and a real life electrical appliances data set are used for practical illustration.

关键词： dependence competing risks bivariate distribution generalized progressive hybrid censoring(GPHC) likelihood estimation Bayesian analysis

Highly active PtAu alloy surface towards selective formic acid electrooxidation

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Journal of Energy Chemistry 2019年第10期28卷 157-162页

作者： liang liang Fateev Vladimir Junjie ge Changpeng Liu Wei Xing Laboratory of Advanced Power Sources Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022JilinChina University of Chinese Academy of Sciences Beijing 100039China Jilin Province Key Laboratory of Low Carbon Chemical Power Sources Changchun 130022JilinChina State Key Laboratory of Electroanalytical Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022JilinChina National Research Center“Kurchatov Institute” Kurchatov sq.1MoscowRussia

The electrochemical oxidation of formic acid has been attracting significant attention in the past few years due to the great potential prospect of direct formic acid fuel cell (DFAFC) in applications, including high theoretical open circuit potential (1.48 V), low fuel crossover, high practical power densities at low temperature, facilitating of proton transport in catalyst layers and low toxicity [1-5].

关键词： Formic acid oxidation PtAu Electrocatalysis DFAFC Nanostructure

Circular RNAs remain peculiarly unclear in biogenesis and function

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Science China(Life Sciences) 2015年第6期58卷 616-618页

作者： CHEN liang SHAN ge School of Life Sciences & CAS Key Laboratory of Brain Function and Disease University of Science and Technology of China

The known complexity of eukaryotic transcriptomes has been greatly expanded due to the identification of a large family of circular RNAs in recent years [1-3]. As a special form of RNA compared to the ＂common＂ linear form, these molecules were first described in 1976, when it was discov- ered that several plant viroids were single-stranded and co- valently closed circular RNAs [4].

关键词： RNA 生物合成圆形线性形式复杂性类病毒家族转录