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SOLUTION OF A KIND OF LINEAR INTERNAL WAVE EQUATION

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Journal of Hydrodynamics 2005年第5期17卷 636-640页

作者： WANG Gang HOU yi-jun ZHENG quan-an Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China Graduate School of the Chinese Academy of Sciences Beijing 100039 China Department of Meteorology University of Maryland Maryland 20742-2425 USA

Considering the effect of horizontal Coriolis parameter and the density compactness of seawater, which were often neglected in internal waves discussion, the governing equation of linear internal waves presented by vertical velocity only will be proposed. Under the assumption that the Brunt- Vaeisaelae frequency is exponential, an accurate analytic solution of it is obtained. Finally, the expressions of wave functions are also given.

关键词： internal wave Boussinesq approximation,Coriolis parameter Brunt-Vaeisaelae frequency

Single link tracking scheme based on UWB localization

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Journal of Systems Engineering and Electronics 2009年第6期20卷 1207-1212页

作者： Xiao Zhu Xiong Hailiang Yu quan yi Kechu State Key Lab. of Integrated Service Networks Xidian Univ. Xi'an 710071 P. R. China School of Electronic Science and Engineering National Univ. of Defense Technology Changsha 410073 P. R. China Inst. of China Electronics Equipment System Engineering Corporation Beijing 100039 P. R. China

To investigate the low-complex and high-precise tracking method, a novel single link tracking scheme based on UWB localization is proposed. Two antenna arrays are settled at the fixed station （FS） to receive the UWB signal from mobile terminal （MT）, one FS is enough for the proposed scheme to track the MT. The UWB multipath detection algorithm for time difference of arrival （TDOA） estimation is presented and TDOA is thus adopted to estimate angle of arrival （AOA）, avoiding the synchronization and complicated beamforming for AOA. The impacts of localization errors, concluding multipath and non-line-of-sight （NLOS） errors are simulated for the proposed track scheme. It is demonstrated that the simulation curve can match the real target moving, and the feasibility of the proposed scheme is proved.

关键词： ultra-wide band localization single-link tracking angle of arrival estimation.

Monomer Migration and Annihilation Processes

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Communications in Theoretical Physics 2005年第5期43卷 953-956页

作者： KEJian-Hong LINZhen-quan ZHUANGYou-yi SchoolofPhysicsandElectronicInformation WenzhouNormalCollegeWenzhou325027China

We propose a two-species monomer migration-annihilation model, in which monomer migration reactions occur between any two aggregates of the same species and monomer annihilation reactions occur between two different species. Based on the mean-field rate equations, we investigate the evolution behaviors of the processes. For the case with an annihilation rate kernel proportional to the sizes of the reactants, the aggregation size distribution of either species approaches the modified scaling form in the symmetrical initial case, while for the asymmetrical initial case the heavy species with a large initial data scales according to the conventional form and the light one does not scale. Moreover,at most one species can survive finally. For the case with aconstant annihilation rate kernel, both species may scale according to the conventional scaling law in the symmetrical case and survive together at the end.

关键词： kinetic behavior migration annihilation scaling law

Generalized Synchronization of Time-Delayed Discrete Systems

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Communications in Theoretical Physics 2009年第6期51卷 1149-1152页

作者： JING Jian-yi MIN Le-quan Information Engineering School University of Science and Technology Beijing Beijing 100083 China Applied Science School University of Science and Technology Beijing Beijing 100083 China

This paper establishes two theorems for two time-delayed （chaotic） discrete systems to achieve timedelayed generalized synchronization （TDGS）. These two theorems uncover the genera/forms of two TDGS systems via a prescribed transformation. As examples, we convert the Lorenz three-dimensional chaotic map to an equal time-delayed system as the driving system, and construct the TDGS driven systems according to the Theorems 1 and 2. Numerical simulations demonstrate the effectiveness of the proposed theorems.

关键词： generalized synchronization time-delayed systems Lorenz three-dimensional chaotic map

New Three-Mode Squeezing Operators Gained via Tripartite Entangled State Representation

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Communications in Theoretical Physics 2008年第1期49卷 225-228页

作者： JIANG Nian-quan FAN Hong-yi College of Physics and Electric Information Wenzhou University Wenzhou 325035 China Department of Material Science and Engineering University of Science and Technology of China Hefei 230026 China

We show that the Agarwal-Simon representation of single-mode squeezed states can be generalized to find new form of three-mode squeezed states. We use the tripartite entangled state representations ｜p, y, z） and ｜x... 详细信息

关键词： tripartite entangled state three-mode squeezing operator IWOP technique

Bose Description of Pauli Spin Operators and Related Coherent States

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Communications in Theoretical Physics 2005年第1期43卷 17-21页

作者： JIANGNian-quan FANHong-yi LUHai-Liang DepartmentofPhysics WenzhouNormalCollegeWenzhou325027China／／DepartmentofMaterialScienceandEngineeringUniversityofScienceandTechnologyofChinaHefei230026China DepartmentofMaterialScienceandEngineering UniversityofScienceandTechnologyofChinaHefei230026China／／DepartmentofPhysicsShanghaiJiaoTongUniversityShanghai200030China DepartmentofPhysics ShanghaiJiaoTongUniversityShanghai200030China

Using both the fermionic-kike and the bosonic-like properties of the Paulispin operators σ_+, σ_-, and σ_z we discuss the derivation of Bose description of the Pauli spinoperators originally proposed by Shigefumi Naka, and deduce another new bosonic representation ofPauli operators. The related coherent states, which are nonlinear coherent state and coherent spinstates for two spins, respectively, are constructed.

关键词： bose description of pauli spin operators nonlinear coherent state coherentspin state

Recognition of hairpin DNA from coil DNA by electrospray mass spectrometry with annealing strategy

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Chinese Chemical Letters 2012年第4期23卷 500-503页

作者： Bo Zheng yi quan Liu Gu Yuan Beijing National Laboratory for Molecular Sciences Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of EducationDepartment of Chemical BiologyCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100086China Shanghai Research Institute of Chemical Industry Shanghai 200062China

This research presented an annealing strategy to identify hairpin DNA from coil DNA with the same base composition but different arrangements using electrospray mass spectrometry（ESI-MS）.A series of single-stranded DNA were annealed with their complementary sequences,*** the five pairs of hairpin DNA and coil DNA were unambiguously distinguished by ESIMS with annealing *** research offers a potential method to probe the DNA structure by comparing with mass spectral characteristics.

关键词： Hairpin DNA Annealing Mass spectrometry

WAMS-based monitoring and control of Hopf bifurcations in multi-machine power systems

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第6期9卷 840-848页

作者： Shao-bu WANG quan-yuan JIANG yi-jia CAO School of Electrical Engineering Zhejiang University Hangzhou 310027 China

A method is proposed to monitor and control Hopf bifurcations in multi-machine power systems using the information from wide area measurement systems (WAMSs). The power method (PM) is adopted to compute the pair of conjugate eigenvalues with the algebraically largest real part and the corresponding eigenvectors of the Jacobian matrix of a power system. The distance between the current equilibrium point and the Hopf bifurcation set can be monitored dynamically by computing the pair of con- jugate eigenvalues. When the current equilibrium point is close to the Hopf bifurcation set, the approximate normal vector to the Hopf bifurcation set is computed and used as a direction to regulate control parameters to avoid a Hopf bifurcation in the power system described by differential algebraic equations (DAEs). The validity of the proposed method is demonstrated by regulating the reactive power loads in a 14-bus power system.

关键词： Wide area measurement system (WAMS) Hopf bifurcations Monitoring of bifurcations Control of bifurcations

Adjusted Log-rank Test with Double Inverse Weighting under Dependent Censoring

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Acta Mathematica Sinica,English Series 2021年第10期37卷 1573-1585页

作者： yi Min GUO Jie ZHOU Liu quan SUN Institute of Applied Mathematics Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190P.R.China University of Chinese Academy of Sciences Beijing 100049P.R.China School of Mathematics of Sciences Capital Normal UniversityBeijing 100048P.R.China

It is a common issue to compare treatment-specific survival and the weighted log-rank test is the most popular method for group comparison. However, in observational studies, treatments and censoring times are usually not independent, which invalidates the weighted log-rank tests. In this paper, we propose adjusted weighted log-rank tests in the presence of non-random treatment assignment and dependent censoring. A double-inverse weighted technique is developed to adjust the weighted log-rank tests. Specifically, inverse probabilities of treatment and censoring weighting are involved to balance the baseline treatment assignment and to overcome dependent censoring, respectively. We derive the asymptotic distribution of the proposed adjusted tests under the null hypothesis, and propose a method to obtain the critical values. Simulation studies show that the adjusted log-rank tests have correct sizes whereas the traditional weighted log-rank tests may fail in the presence of non-random treatment assignment and dependent censoring. An application to oropharyngeal carcinoma data from the Radiation Therapy Oncology Group is provided for illustration.

关键词： Adjusted log-rank test dependent censoring double inverse weighting survival data