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Influence of the penetration of adjacent X-section cast-in-place concrete(XCC)pile on the existing XCC pile in sand

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Journal of Zhejiang university-Science A(applied Physics & Engineering) 2024年第7期25卷 557-572页

作者： Peng ZHOU Jianhui xu Changjie xu Guangwei CAO Jie CUP xuanming DING School of Civil Engineering and Architecture State Key Laboratory of Performance Monitoring and Protecting of Rail Transit InfrastructureEast China Jiaotong UniversityNanchang330013China Guangdong Key Laboratory of Earthquake Engineering and Application technology Earthquake Engineering Research&Test CenterGuangzhou UniversityGuangzhou510006China Key Laboratory of New technology for the Construction of Cities in Mountain Areas College of Civil EngineeringChongqing UniversityChongqing400045China Zijin School of Geology and Mining Fuzhou UniversityFuzhou350116China

A series of small-scale 1g X-section cast-in-place concrete(XCC)pile-penetration model tests were conducted to study the effects of soil density and pile geometry on the lateral responses of an existing pile and the variations in surrounding soil *** results showed that the bending patterns of existing XCC piles varied with penetration *** lateral response of the existing pile was sensitive to the change in relative density and pile *** example,the bending moment of the existing pile increased along with these *** development of the radial stressσ′r/σ′v0 of the soil around an existing pile showed different trends at various depths during the penetration of the adjacent ***,the change in radial stress during the penetration of the XCC pile did not exhibit the“h/R effect”that was observed in the free-field soil,due to the shielding effect of the existing *** peak value of radial stressσ′r_max/σ′v0 decreased exponentially as the radial distance r/R *** attenuation ofσ′r_max/σ′v0 with r/R in the loose sand was faster than in the medium-dense or dense ***σ′r_max/σ′v0 at the same soil location increased with the cross-section geometry parameter.

关键词： X-section cast-in-place concrete(XCC)pile Test Penetration Sand Lateral response Radial stress

Model-free method for LQ mean-field social control problems with one-dimensional state space

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Control Theory and technology 2024年第3期22卷 479-486页

作者： Zhenhui xu Tielong Shen School of Engineering Tokyo Institute of TechnologyTokyo 152-8550Japan department of Engineering and applied Sciences Sophia UniversityTokyo 102-8554Japan

This paper presents a novel model-free method to solve linear quadratic(LQ)mean-field control problems with one-dimensional state space and multiplicative *** focus is on the infinite horizon LQ setting,where the conditions for solution either stabilization or optimization can be formulated as two algebraic Riccati equations(AREs).The proposed approach leverages the integral reinforcement learning technique to iteratively solve the drift-coefficient-dependent stochastic ARE(SARE)and other indefinite ARE,without requiring knowledge of the system dynamics.A numerical example is given to demonstrate the effectiveness of the proposed algorithm.

关键词： Mean-field control Social optima Infinite horizon Reinforcement learning

Synthesis and characterization of iron clusters with an icosahedral [Fe@Fe12]16+ Core

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National Science Review 2024年第4期11卷 123-129页

作者： Gan xu Yun-Shu Cui xue-Lian Jiang Cong-Qiao xu Jun Li xu-Dong Chen Jiangsu Collaborative Innovation Center of Biomedical Functional Materials and Jiangsu Key Laboratory of New Power Batteries School of Chemistry and Materials Science Nanjing Normal University department of Chemistry and Guangdong Provincial Key Laboratory of Catalytic Chemistry Southern University of Science and Technology department of Chemistry and Engineering Research Center of Advanced Rare-Earth Materials of Ministry of Education Tsinghua University State Key Laboratory of Coordination Chemistry Nanjing University

Iron-metal clusters are crucial in a variety of critical biological and material systems,including metalloenzymes,catalysts,and magnetic storage ***,a synthetic high-nuclear iron cluster has been absent due to the extreme difficulty in stabilizing species with direct iron-iron *** this work,we have synthesized,crystallized,and characterized a（Tp*）4W4S12(Fe@Fe12) cluster(Tp*=tris（3,5-dimethyl-1-pyrazolyl）borate（1-）),which features a rare trideca-nuclear,icosahedral[Fe@Fe12] cluster core with direct multicenter iron-iron bonding between the interstitial iron（Fei） and peripheral irons（Fep）,as well as Fep…Fepferromagnetic *** chemistry studies reveal that the stability of the cluster arises from the 18-electron shell-closing of the [Fe@Fe12]16+core,assisted by its bonding interactions with the peripheral tridentate [（Tp*）WS3]4-ligands which possess both S→Fe donation and spin-polarized Fe-Wσ *** ground-state electron spin is theoretically predicted to be S=32/2 for the *** existence of low oxidation-state（OS～+1.23） iron in this compound may find interesting applications in magnetic storage,spintronics,redox chemistry,and cluster catalysis.

关键词： Fe13 cluster iron-sulfur cluster low-valence iron iron−iron bond high spin complex

On hydraulic falls of two-layer flow

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Acta Oceanologica Sinica 1996年第2期15卷 179-191页

作者： xu Zhaoting Lou Shunli Tian Jiwei and Samuel Shan pn Shen(Institute of Physical Deeanopaphy and Physical oceanography Laboratory, Ocean university Of Qngdao, Qngdao266003, china department of mathematics and applied mathematics institute, university of A Institute of Physical Oceanography Physical Oceanography Laboratory Ocean University of Qingdao Qingdao 266003 China department of mathematics Applied Mathematics Institute University of Alberta Edmonton Alta. T6G 2G1 Canada

Hydraulic falls and asymptotic mean levels of two-layer flow are determined by means of AfKdV equation in phase coordinate theoretically. By present theory, the hydraulic falls Hf depend on a characteristic value of the MfKdV equation at the subcritical cutoff points It is proved that the differences of the asymptotic mean levels upstream and downstream at the subcritical cutoff points are equal to 2 A relation between and the asymptotic mean levels at the subcritical cutoff points is also found in terms of the solution of the hydraulic falls. Because the AfKdV equation is derived based on the small topography assumption, for semicircular topography the valid region of this theory is α< 0. 35, in which α is radius of the semicircular topography. An experiment is carried out to examine the theory of the present paper. From comparisons between the theoretical and experimental results. it is shown that they are in better agreement. Under conditions of different stratified parameters, the hydraulic falls of two-layer flow are predicted theoretically. This work was supered by the Foundation of the State Education COmmission 'The dynamics of upper ocean'.

关键词： fKdV equation hydraulic fall two-layer flow subcritical cutoff point

A CIDNP STUDY OF THE PHOTOREACTIONS OF METHYLFURANS WITH CHLORANIL

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Chinese Chemical Letters 1993年第4期4卷 327-330页

作者： Ling jiang CHENG~(1,2) Han Cheng YUAN~3 Er Cheng LI~2 Bao Zhen YAN~3 Jian Hua xu~4 Guang Zhi xu~2 1 Institute of Photographic Chemistry,Chinese Academy Of Sciences,beijing 100101 2 Institute of Chemistry,Chinese Academy of Sciences,beijing 100080 3 department of applied Chemistry,beijing Institute of Chemical technology,beijing 100029 4 department of Chemistry,Nanjing university,Nanjing,Jiangsu 210008

The CIDNP observations indicated that photoreaction of methylfurans with chloranil resulted not only furylmethyl hydroxyphenyl ethers via radical pairs but induced furyl radical isomerization to the derivatives of cyc... 详细信息

关键词： CIDNP Th A CIDNP STUDY OF THE PHOTOREACTIONS OF METHYLFURANS WITH CHLORANIL

Bioinspired 3D flexible devices and functional systems

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National Science Review 2024年第3期11卷 271-295页

作者： xu Cheng Zhangming Shen Yihui Zhang applied Mechanics Laboratory Department of Engineering Mechanics Tsinghua University Laboratory of Flexible Electronics technology Tsinghua University

Flexible devices and functional systems with elaborated three-dimensional(3D) architectures can endow better mechanical/electrical performances, more design freedom, and unique functionalities, when compared to their two-dimensional(2D) counterparts. Such 3D flexible devices/systems are rapidly evolving in three primary directions, including the miniaturization, the increasingly merged physical/artificial intelligence and the enhanced adaptability and capabilities of heterogeneous *** challenges exist in this emerging research area, such as relatively poor controllability in the locomotion of soft robotic systems, mismatch of bioelectronic interfaces, and signal coupling in multi-parameter sensing. By virtue of long-time–optimized materials, structures and processes, natural organisms provide rich sources of inspiration to address these challenges, enabling the design and manufacture of many bioinspired 3D flexible devices/systems. In this Review, we focus on bioinspired 3D flexible devices and functional systems, and summarize their representative design concepts, manufacturing methods, principles of structure-function relationship and broad-ranging applications. Discussions on existing challenges, potential solutions and future opportunities are also provided to usher in further research efforts toward realizing bioinspired 3D flexible devices/systems with precisely programmed shapes,enhanced mechanical/electrical performances, and high-level physical/artificial intelligence.

关键词： bioinspired designs biomimetic 3D structures 3D flexible electronics 3D functional systems direct 3D manufacture 2D-to-3D assembly

Synthesis and characterization of three new solid polyoxometalates based on Wells-Dawson-derived sandwich-type polyanions [Co_(4)(H_(2)O)_(2)(P_(2)W_(15)O_(56))_(2)]^(16-)

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Journal of Zhejiang university-Science A(applied Physics & Engineering) 2024年第3期25卷 268-274页

作者： Jjijie YE xuan xu Chuande WU department of Chemistry Zhejiang UniversityHangzhou 310058China

Three polyoxometalate-based hybrid coordination materials,[Co_(8)(H_(2)O)_(34)(pz)_(2){Co_(4)(H_(2)O)_(2)P_(4)W_(30)O_(112)}]·16H_(2)O(compound 1),[H_(3)O]_(4)[Co_(6)(H_(2)O)_(22)(pz)_(2){Co_(4)(H_(2)O)_(2)P_(4)W_(30)O_(112)}]·21H_(2)(compound 2),and[H_(3)O]_(4)[Co_(6)(H_(2)O)_(22){Co_(4)(H_(2)O)_(2)P_(4)W_(30)O_(112)}]·29H_(2)O(compound 3)(pz-pyrazine),were built from the linkage of[Co_(4)(H_(2)O)_(2)(P_(2)W_(15)O_(56)_(2)]^(16-)-(abbreviated as{Co_(4)P_(4)W_(30})polyanions and pz and/or cobalt(II)*** compounds 1 and 2 consisted of the same components,their lamellar networks were quite *** inorganic lamellar network in compound 3 was constructed by connecting{Co_(4)P_(4)W_(30)}units with cobalt(I)*** work demonstrates that the coordination modes of{Co_(4)P_(4)W_(30)}are very sensitive to synthesis conditions,while the ring-belt tetrametals are easily substituted by different transition metal cations under mild reaction conditions.

关键词： Cobalt Crystal structure Cyclic voltammetry Hybrid Polyoxometalate

Discovery of Partial Differential Equations from Highly Noisy and Sparse Data with Physics-Informed Information Criterion

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Research 2024年第1期2023卷 247-259页

作者： Hao xu Junsheng Zeng Dongxiao Zhang BIC-ESAT EREand SKLTCSCollege of EngineeringPeking UniversityBeijing 100871P.R.China Institute of applied Physics and Computational mathematics Beijing 100088P.R.China Eastern Institute for Advanced Study Eastern Institute of TechnologyNingbo 315200ZhejiangP.R.China National Center for applied mathematics Shenzhen(NCAMS) Southern University of Science and TechnologyShenzhen 518055GuangdongP.R.China department of mathematics and Theories Peng Cheng LaboratoryShenzhen 518000GuangdongP.R.China

Data-driven discovery of partial differential equations(PDEs)has recently made tremendous progress,and many canonical PDEs have been discovered successfully for proof of ***,determining the most proper PDE without prior references remains challenging in terms of practical *** this work,a physics-informed information criterion(PIC)is proposed to measure the parsimony and precision of the discovered PDE *** proposed PIC achieves satisfactory robustness to highly noisy and sparse data on 7 canonical PDEs from different physical scenes,which confirms its ability to handle difficult *** PIC is also employed to discover unrevealed macroscale governing equations from microscopic simulation data in an actual physical *** results show that the discovered macroscale PDE is precise and parsimonious and satisfies underlying symmetries,which facilitates understanding and simulation of the physical *** proposition of the PIC enables practical applications of PDE discovery in discovering unrevealed governing equations in broader physical scenes.

关键词： process canonical proof

Semantic Session Analysis for Web Usage Mining

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Wuhan university Journal of Natural Sciences 2007年第5期12卷 773-776页

作者： ZHANG Hui SONG Hantao xu Xiaomei department of Computer Science and Engineering Beijing Institute of Technology Beijing 100081 China

A semantic session analysis method partitioning Web usage logs is presented. Semantic Web usage log preparation model enhances usage logs with semantic. The Markov chain model based on ontology semantic measurement is used to identifying which active session a request should belong to. The competitive method is applied to determine the end of the sessions. Compared with other algorithms, more successful sessions are additionally detected by semantic outlier analysis.

关键词： Web usage mining Web log preparation session analysis