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A Separation Theorem for Stochastic Singular Linear Quadratic Control Problem with Partial Information

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Acta Mathematicae Applicatae Sinica 2013年第2期29卷 303-314页

作者： Hong-ji MA ting hou College of Science Shandong University of Science and Technology Department of Systems and Control Beijing University of Aeronautics and Astronautics

In this paper, we provide a separation theorem for the singular linear quadratic （LQ） control problem of ItS-type linear systems in the case of the state being partially observable. Above all, the Kalmam Bucy filtering of the dynamics is given by means of Girsanov transformation, by which the suboptimal feedback control of the LQ problem is determined. Furthermore, it is shown that the well-posedness of the LQ problem is equivalent to the solvability of a generalized differential Riccati equation （GDRE）.

关键词： singular optimal control Kalman-Bucy filtering separation theorem linear systems generalizeddifferential Riccati equation

Additive Maps Preserving Nilpotent Perturbation of Scalars

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Acta Mathematica Sinica,English Series 2019年第3期35卷 407-426页

作者： ting ZHANG Jin Chuan hou School of Mathematics Taiyuan University of Technology Department of Mathematics Shanxi University

Let X be a Banach space over F(= R or C) with dimension greater than 2. Let N(X) be the set of all nilpotent operators and B_0(X) the set spanned by N(X). We give a structure result to the additive maps on FI + B_0(X) that preserve rank-1 perturbation of scalars in both directions. Based on it, a characterization of surjective additive maps on FI + B_0(X) that preserve nilpotent perturbation of scalars in both directions are obtained. Such a map Φ has the form either Φ(T) = cAT A^(-1)+ φ(T)I for all T ∈ FI + B_0(X) or Φ(T) = cAT*A^(-1)+ φ(T)I for all T ∈ FI + B_0(X), where c is a nonzero scalar,A is a τ-linear bijective transformation for some automorphism τ of F and φ is an additive *** addition, if dim X = ∞, then A is in fact a linear or conjugate linear invertible bounded operator.

关键词： Banach spaces nilpotent operators perturbations additive preservers

Molecular Chaperone-Dependent Polymer Translocation through Nanopores: The Effects of Chaperone Concentration and Chaperone-Polymer Interaction

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Chinese Journal of Polymer Science 2024年第1期42卷 125-132,I0011页

作者： Chang-Sheng Zuo Kang Wang Li-zhen Sun ting-ting Sun Department of Physics Zhejiang University of Science and TechnologyHangzhou 310023China Department of Applied Physics Zhejiang University of TechnologyHangzhou 310014China

The polymer translocation through a nanopore from a donor space(or named cis side) to a receiver space(trans side) in the chaperone-induced crowded environment has attracted increasing attention in recent years due to its significance in biological systems and technological applications. In this work, we mainly focus on the effects of chaperone concentration and chaperone-polymer interaction on the polymer translocation. By assuming the polymer translocation to be a quasi-equilibrium process, the free energy F of the polymer can be estimated by Rosenbluth-Rosenbluth method and then the translocation time τ can be calculated by Fokker-Plank equation based on the obtained free energy landscape. Our calculation results show that the translocation time can be controlled by independently tuning the chaperone concentration and chaperone-polymer interaction at the cis side or the trans side. There exists a critical chaperone-polymer attraction ε~*=-0.2 at which the volume exclusion and interaction effects of the chaperone can balance each other. Additionally, we also find that at large chaperone-polymer attraction, the translocation time is mainly governed by the diffusion coefficient of the polymer.

关键词： Polymer translocation Rosenbluth-Rosenbluth method Fokker-Plank equation Free energy landscapes

A new meshless approach for bending analysis of thin plates with arbitrary shapes and boundary conditions

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Frontiers of Structural and Civil Engineering 2022年第1期16卷 75-85页

作者： Wei DU Xiaohua ZHAO Huiming hou zhen WANG Department of Civil and Environmental Engineering Shantou UniversityShantou 515063China Key Laboratory of Structure and Wind Tunnel of Guangdong Higher Education Institutes Shantou 515063China

An efficient and meshfree approach is proposed for the bending analysis of thin *** approach is based on the choice of a set of interior points,for each of which a basis function can be *** deflection is then approximated as the linear combination of those basis *** traditional meshless methods,present basis functions are defined in the whole domain and satisfy the governing differential equation for ***,no domain integration is needed,while the unknown coefficients of deflection expression could be determined through boundary conditions by using a collocation point *** efficiency and accuracy of the approach are shown through numerical results of plates with arbitrary shapes and boundary conditions under various loads.

关键词： plate bending meshless method collocation

Characteristics of coastline changes in China's Mainland since the early 1940s

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Science China Earth Sciences 2016年第9期59卷 1791-1802页

作者： hou XiYong WU ting hou Wan CHEN Qing WANG YuanDong YU LiangJu Yantai Institute of Coastal Zone Research Chinese Academy of Sciences Yantai 264003 China University of Chinese Academy of Sciences Beijing 100049 China

Based on multi-temporal topographic maps, remote sensing images and field surveys covering the entire coastal zone of China's Mainland, the coastlines of six periods since the early 1940s were extracted. Coastline changes over the last 70 years were then analyzed in terms of coastline structure, coastline fractals, coastline change rates, land-sea patterns, and bay areas. The results showed that mainland coastline structure changed dramatically, and due to the significant coastline artificialization mainly driven by sea reclamation and coastal engineering, the remaining natural coastline merely accounts for less than one third at present. Coastline fractal dimension represented an overall spatial pattern of ＂north 〈 entirety 〈 south＂; however, the discrepancy between the north and south coast was apparently narrowed due to dramatic coastline artificialization of northern China which in turn altered the whole pattern. Patterns and processes of land-sea interchange along the mainland coast were complex and varied spatially and temporally, with over 68% advancing toward sea and 22% retreating toward land. The net growth of land area was nearly 14.2 ×10^3 km2 with an average growth rate of 202.82 km2 al; and coast retreat was characterized by area decrease of 93 bays with a magnitude of 10.1 ×10^3 km2 and an average shrinking rate up to 18.19% or an average shrinking speed up to 144.20 km2 a-1, among which the total area of Bohai shrunk by 7.06%, with an average annual loss amounting to 82 km2. The dramatic coastline changes along China's Mainland have brought about kinds of challenges to the coastal environment, therefore the integrated management, effective environment protection and sustainable utilization of coastlines is urgent.

关键词： China Mainland coastline Coastline structure Coastline fractal dimension Coastline change rate Land-Sea change Bay area

A Study on Performance and Reliability of Urethral Valve Driven by Ultrasonic-vaporized Steam

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International Journal of Automation and computing 2020年第5期17卷 752-762页

作者： zhen Hu Xiao Li ting Guan School of Electromechanical Engineering Guangdong University of TechnologyGuangzhou 510006China Guangzhou General Hospital of Guangzhou Military Command Guangzhou 510006China

The aim of this study is to investigate the performance and reliability of urethral valve driven by ultrasonic-vaporized *** performance model of urethral valve is established to analyze the driving and opening/closing performances of urethral *** reliability model of urethral valve is obtained,and the reliability simulation algorithm is proposed to calculate the reliability index of urethral *** numerical simulation and experimental results show that urethral valve has a good opening/closing performance,the driving performance can be improved by increasing ultrasonic intensity,radiation area and ultrasonic frequency,and the corrosion and aging of driving bags are the weak links of urethral valve.

关键词： Urethral valve ultrasonic opening/closing performance driving performance reliability

Resonance-Enhanced Photon Excitation Spectroscopy of the Even-Parity Autoionizing Rydberg States of Xe

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Chinese Journal of Chemical Physics 2008年第5期21卷 401-406页

作者： Chun-yan Li ting-ting Wang Jun-feng zhen Qun Zhang Yang Chen Hefei National Laboratory for Physical Sciences at Microscale Department of Chemical Physics University of Science and Technology of China Hefei 230026 China

Xenon atoms were produced in their metastable states 5p^56s[3/2]2 and 5p^56s＇[1/2]0 in a pulsed DC discharge in a beam, and subsequently excited to the even-parity autoionizing Rydberg states 5p^5np＇ [3/2] 1,[1/2] 1, and 5p^5nf＇ [5/2] 3 using single photon excitation. The excitation spectra of the even-parity autoionizing resonance series from the metastable 129Xe were obtained by recording the autoionized Xe＋ with time-of-flight ion detection in the photon energy range of 28000-42000 cm-1. A wealth of autoionizing resonances were newly observed, from which more precise and systematic spectroscopic data of the level energies and quantum defects were derived.

关键词： Xe Pulsed DC discharge Resonance-enhanced photon excitation spectroscopy Autoionizing resonance

K3PO4-Promoted Cyclopropanation of Electron-deficient Alkenes with 2-Bromo-1,3-Propanedione Compounds

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Chemical Research in Chinese Universities 2019年第6期35卷 1002-1007页

作者： CHEN Zhanguo WEN ting hou Dan Key Laboratory for Macromolecular Science of Shaanxi Province School of Chemistry and Chemical EngineeringShaanxi Normal UniversityXi'an 710119P.R.China

An easy and efficient method for the synthesis of multisubstituted cyclopropane derivatives from electron-deficicent alkenes with 2-bromo-1,3-propanedione compounds was *** this method,ethylα-cyanocinnamate derivatives 1 andβ,β-dicyanostyrene derivatives 4 can all smoothly reacted with 2-bromo-1,3-propanedione compounds 2 to afford the corresponding multisubstituted cyclopropane derivatives 3 and 5 in good to excellent yields(up to 100%)promoted by anhydrous K3PO4 in DMF at room temperature,respectively.A possible mechanism of this reaction was *** of all the products were confirmed by ^1H NMR,^13C NMR and HRMS.

关键词： Cyclopropanation Multisubstituted cyclopropane derivative Electron-deficicent alkene 2-Bromo-l,3-propanedione compound

Fracture prediction in the tight-oil reservoirs of the Triassic Yanchang Formation in the Ordos Basin,northern China

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Petroleum Science 2017年第1期14卷 1-23页

作者： Wen-Tao Zhao Gui-ting hou The Key Laboratory of Orogenic Belts and Crustal Evolution of Ministry of Education School of Earth and Space SciencesPeking UniversityBeijing 100871China China Huaneng Clean Energy Research Institute Beijing 102209China Petro China Research Institute of Petroleum Exploration and Development Beijing 100083China

It is important to predict the fracture distribution in the tight reservoirs of the Ordos Basin because fracturing is very crucial for the reconstruction of the low-permeability reservoirs. Three-dimensional finite element models are used to predict the fracture orientation and distribution of the Triassic Yanchang Formation in the Longdong area, southern Ordos Basin. The numerical modeling is based on the distribution of sand bodies in the Chang 7a and 72 members, and the different forces that have been exerted along each boundary of the basin in the Late Mesozoic and the Cenozoic. The calculated results demonstrate that the fracture orientations in the Late Mesozoic and the Ceno- zoic are NW-EW and NNE-ENE, respectively. In this paper, the two-factor method is applied to analyze the distribution of fracture density. The distribution maps of predicted fracture density in the Chang 71 and 72 members are obtained, indicating that the tectonic movement in the Late Mesozoic has a greater influence on the fracture development than that in the Cenozoic. The average fracture densities in the Chang 71 and 72 members are similar, but there are differences in their distributions. Compared with other geological elements, the lithology and the layer thickness are the primary factors that control the stress distribution in the study area, which further determine the fracture distribution in the stable Ordos Basin. The predicted fracture density and the two-factor method can be utilized to guide future exploration in the tight-sand reservoirs.

关键词： Ordos Basin - Yanchang Formation Fractureprediction Finite element modeling Two-factor methodTight-sand reservoirs