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Journal of Systems Science & Complexity 2023年第1期36卷 273-293页

作者： chen juan ZHUANG Bo Aliyun School of Big Data Changzhou UniversityChangzhou 213164China School of Information Engineering Binzhou UniversityBinzhou 256600China

This paper addresses a boundary state feedback control problem for a coupled system of time fractional partial differential equations(PDEs)with non-constant(space-dependent)coefficients and different-type boundary conditions(BCs).The BCs could be heterogeneous-type or ***,this coupled system has different BCs at the uncontrolled side for heterogeneous-type and the same BCs at the uncontrolled side for *** main contribution is to extend PDE backstepping to the boundary control problem of time fractional PDEs with space-dependent parameters and different-type *** the backstepping transformation and the fractional Lyapunov method,the Mittag-Leffler stability of the closed-loop system is obtained.A numerical scheme is proposed to simulate the fractional case when kernel equations have not an explicit solution.

关键词： Boundary control coupled systems heterogeneous mittag-leffler stability time fractional PDEs with space-dependent coefficients

Powers of General Digital Sums

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Acta Mathematica Sinica,English Series 2010年第6期26卷 1133-1138页

作者： Feng juan chen School of Mathematical Sciences Nanjing Normal University Nanjing 210046 P. R. China and Department of Mathematics Suzhou University Suzhou 215006 P. R. China

Let m0,m1,m2,…be positive integers with mi〉 2 for all i. It is well known that each nonnegative integer n can be uniquely represented as n= a0 ＋ a1m0＋a2m0m1＋…＋atm0m1m2…mt-1,where 0≤ai≤mi-1 for all i and at≠*** each fi be a function defined on {0,1,2…,mi-1} with fi（0）=*** S（n）=i=0∑tfi（ai）.In this paper, we give the asymptotic formula for x^-1∑n≤xS（n）^k,where k is a positive integer.

关键词： digital sum arithmetic function asymptotic formula

Two 8-node quadrilateral spline elements by B-net method

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Acta Mechanica Sinica 2012年第6期28卷 1620-1629页

作者： juan chen Chong-Jun Li School of Mathematics and Quantitative Economics Dongbei University of Finance and Economics School of Mathematical Sciences Dalian University of Technology

Isoparametric quadrilateral elements are widely used in the finite element method, but the accuracy of the isoparametric quadrilateral elements will drop obviously deteriorate due to mesh distortions. Spline functions have some properties of simplicity and conformality. Two 8-node quadrilateral elements have been developed using the trian- gular area coordinates and the B-net method, which can ex- actly model the quadratic field for both convex and concave quadrangles. Some appropriate examples are employed to evaluate the performance of the proposed elements. The nu- merical results show that the two spline elements can obtain solutions which are highly accurate and insensitive to mesh distortions.

关键词： Spline finite element B-net method Quadri-lateral element - Bivariate spline interpolation The secondorder completeness

Development of quadrilateral spline thin plate elements using the B-net method

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Acta Mechanica Sinica 2013年第4期29卷 567-574页

作者： juan chen Chong-Jun Li School of Mathematics and Quantitative Economics Dongbei University of Finance and Economics School of Mathematical Sciences Dalian University of Technology

The quadrilateral discrete Kirchhoff thin plate bending element DKQ is based on the isoparametric element Q8, however, the accuracy of the isoparametric quadrilateral elements will drop significantly due to mesh distortions. In a previous work, we constructed an 8-node quadrilateral spline element L8 using the triangular area coordinates and the B- net method, which can be insensitive to mesh distortions and possess the second order completeness in the Cartesian co- ordinates. In this paper, a thin plate spline element is devel- oped based on the spline element L8 and the refined tech- nique. Numerical examples show that the present element indeed possesses higher accuracy than the DKQ element for distorted meshes.

关键词： Spline finite element ~ Refined quadrilateral el-ement ~ Discrete Kirchhoff plate element ~ Triangular areacoordinates ~ B-net method

Emerging roles of non-coding RNAs in epigenetic regulation

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Science China(Life Sciences) 2016年第3期59卷 227-235页

作者： juan chen Yuanchao Xue Key Lab of RNA biology Institute of Biophysics Chinese academy of Sciences

Recent deep sequencing surveys of mammalian genomes have unexpectedly revealed pervasive and complex transcription and identified tens of thousands of RNA transcripts that do not code for proteins. These non-coding RNAs(nc RNAs) highlight the central role of RNA in gene regulation. nc RNAs are arbitrarily divided into two main groups: The first includes small RNAs, such as mi RNAs, pi RNAs, and endogenous si RNAs, that usually range from 20 to 30 nt, while the second group includes long non-coding RNAs(lnc RNAs), which are typically more than 200 nt in length. These nc RNAs were initially thought to merely regulate gene expression at the post-transcriptional level, but recent studies have indicated that nc RNAs, especially lnc RNAs, are extensively associated with diverse chromatin remodeling complexes and target them to specific genomic loci to alter DNA methylation or histone status. These findings suggest an emerging theme of nc RNAs in epigenetic regulation. In this review, we discuss the wide spectrum of nc RNAs in the regulation of DNA methylation and chromatin state, as well as the key questions that needs to be investigated and acknowledging the elegant design of these intriguing macromolecules.

关键词： non-coding RNAs lncRNAs DNA methylation chromatin remodeling

A 3D pyramid spline element

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Acta Mechanica Sinica 2011年第6期27卷 986-993页

作者： juan chen Chong-Jun Li Wan-Ji chen School of Mathematics and Quantitative Economics Dongbei University of Finance and Economics 116025 Dalian China School of Mathematical Sciences Dalian University of Technology116024 Dalian China Key Laboratory of Liaoning Province for Composite Structural Analysis of Aerocraft and Simulation Shenyang Aerospace University 110136 Shenyang China State Key Laboratory for Structural Analysis of Industrial Equipment Dalian University of Technology 116024 Dalian China

In this paper,a 13-node pyramid spline element is derived by using the tetrahedron volume coordinates and the B-net method,which achieves the second order completeness in Cartesian *** appropriate examples were employed to evaluate the performance of the proposed *** numerical results show that the spline element has much better performance compared with the isoparametric serendipity element Q20 and its degenerate pyramid element P13 especially when mesh is distorted,and it is comparable to the Lagrange element *** has been demonstrated that the spline finite element method is an efficient tool for developing high accuracy elements.

关键词： Spline finite element Pyramid element The second order completeness B-net method

Construction of n-sided polygonal spline element using area coordinates and B-net method

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Acta Mechanica Sinica 2010年第5期26卷 685-693页

作者： juan chen Chong-Jun Li Wan-Ji chen School of Mathematical Sciences Dalian University of Technology 116024 Dalian China State Key Laboratory for Structural Analysisof Industrial Equipment Dalian University of Technology116024 Dalian China Institute for Structural Analysis of Aerocraft Shenyang Institute of Aeronautical Engineering110136 Shenyang China

In general, triangular and quadrilateral elements are commonly applied in two-dimensional finite element methods. If they are used to compute polycrystalline materials, the cost of computation can be quite significant. Polygonal elements can do well in simulation of the materials behavior and provide greater flexibility for the meshing of complex geometries. Hence, the study on the polygonal element is a very useful and necessary part in the finite element method. In this paper, an n-sided polygonal element based on quadratic spline interpolant, denoted by PS2 element, is presented using the triangular area coordinates and the B-net method. The PS2 element is conforming and can exactly model the quadratic field. It is valid for both convex and non-convex polygonal element, and insensitive to mesh distortions. In addition, no mapping or coordinate transformation is required and thus no Jacobian matrix and its inverse are evaluated. Some appropriate examples are employed to evaluate the performance of the proposed element.

关键词： Finite element method n-sided polygonalelement - Bivariate spline interpolation The second ordercompleteness

On the Largest Prime Factor of Shifted Primes

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Acta Mathematica Sinica,English Series 2017年第3期33卷 377-382页

作者： Feng juan chen Yong Gao chen School of Mathematical Sciences Soochow University School of Mathematical Sciences and Institute of Mathematics Nanjing Normal University

For any integer n ≥ 2, let P（n） be the largest prime factor of n. In this paper, we prove 1 This that the number of primes p 〈 x with P（p- 1） ≥ pC is more than （1 -c＋o（1））π（x） for 0 〈 c 〈 1/2 extends... 详细信息

关键词： Prime factor shifted prime

An Improved Cooperative Team Spraying Control of a Diffusion Process With a Moving or Static Pollution Source

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IEEE/CAA Journal of Automatica Sinica 2020年第2期7卷 494-504页

作者： juan chen Baotong Cui Yang Quan chen Bo Zhuang Key Laboratory of Advanced Process Control for Light Industry(Ministry of Education)and School of IoT Engineering Jiangnan UniversityWuxi 214122China Mechatronics Embedded Systems and Automation LaboratoryUniversity of CaliforniaMerced CA 95343 USA

This paper is concerned with a control problem of a diffusion process with the help of static mesh sensor networks in a certain region of interest and a team of networked mobile actuators carrying chemical *** major contribution of this paper can be divided into three parts:the first is the construction of a cyber-physical system framework based on centroidal Voronoi tessellations(CVTs),the second is the convergence analysis of the actuators location,and the last is a novel proportional integral(PI)control method for actuator motion planning and neutralizing control(e.g.,spraying)of a diffusion process with a moving or static pollution source,which is more effective than a proportional(P)control *** optimal spraying control cost function is ***,the minimization problem of the spraying amount is ***,a new CVT algorithm based on the novel PI control method,henceforth called PI-CVT algorithm,is introduced together with the convergence analysis of the actuators location via a PI control ***,a modified simulation platform called diffusion-mobile-actuators-sensors-2-dimension-proportional integral derivative(Diff-MAS2D-PID)is *** addition,a numerical simulation example for the diffusion process is presented to verify the effectiveness of our proposed controllers.

关键词： Centroidal Voronoi tessellations(CVTs) diffusion processes mobile actuator-sensor networks(MAS-Net) PI control

Two New Borates Built by Different Types of{B_(9)}Cluster Units

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Chemical Research in Chinese Universities 2022年第3期38卷 744-749页

作者： chen juan WANG Jiajia chen Chongan YANG Guoyu Key Laboratory of Cluster Science Ministry of EducationSchool of Chemistry and Chemical EngineeringBeijing Institute of TechnologyBeijing102488P.R.China

Two new belt-like borates Na_(4)[B_(9)O_(14)(OH)_(3)]·0.5H_(2)O(1)and Na_(5)[B_(9)O_(14)(OH)_(4)](2)have been synthesized under solvothermal *** compounds contain unprecedented B_(9)O_(16)(OH)_(n)^((n+5))−[n=3(1),4(2)]clusters,which are constructed from four B_(3)O_(3) rings via three BO_(4) *** 1 exhibits a rare 1D belt with two types of 8-membered ring(MR)windows based on B_(9)O_(16)(OH)_(3)^(8−) *** 2 features two different 1D belts built by different B_(9)O_(16)(OH)_(4)^(9−) units,which is first discovered in borate ***-Vis diffuse reflectance spectra reveal that compounds 1 and 2 have the cut-off edges below 190 nm,indicating that they may have potential application in deep UV(DUV)region.

关键词： Oxoboron cluster Synthesis Borate Supramolecular framework Structure