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Journal of Computational Mathematics 1997年第4期15卷 365-384页

作者： Zhi-ming Chen (Institute of Mathematics, chinese academy of Sciences, Beijing, China) 中科院数学所北京

In this paper we seek the solutions of the time dependent Ginzburg-Landau model for type-Ⅱ superconductors such that the associated physical observables are spatially periodic with respect to some lattice whose basic lattice cell is not necessarily rectangular. After appropriately foring the gange, the model can be formulated as a system of nonlinear parabolic partial differential equations with quasi-periodic boundary conditions. We first give some results concerning the existence, uniqueness and regularity of solutions and then we propose a semiimplicit finite element scheme solving the system of nonlinear partial dmerential equations and show the optimal error estimates both in the L2 and energy *** also report on some numerical results at the end of the paper.

关键词： Math QT MODELLING AND NUMERICAL SOLUTIONS OF A GAUGE PERIODIC TIME DEPENDENT GINZBURG-LANDAU MODEL FOR TYPE SUPERCONDUCTORS

Subspace Search Method for Quadratic Programming With BoxConstraints

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Journal of Computational Mathematics 1999年第3期17卷 307-314页

作者： Zi-luan Wei(ICMSEC, chinese academy of Sciences, Beijing 100080, China) 中科院计算数学与科学工程计算所北京

A subspace search method for solving quadratic programming with box constraints is presented in this paper. The original problem is divided into many independent subproblem at an initial point, and a search direction is obtained by solving each of the subproblem, as well as a new iterative point is determined such that the value of objective function is decreasing. The convergence of the algorithm is proved under certain assumptions, and the numerical results are also given.

关键词： subspace search method quadratic programing matrix splitting

A NOTE ON THE CONSTRUCTION OF SYMPLECTIC SCHEMES FOR SPLITABLE HAMILTONIAN H = H^((1)) + H^((2)) + H^((3))

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Journal of Computational Mathematics 2002年第1期20卷 89-96页

作者： Yi-fa Tang (LSEC ICMSEC academy of Mathematics and System Sciences, chinese academy of Sciences, Beijing 100080, China) 中科院数学与系统科学院 LSEC ICMSEC CAS 北京 100080

In this note, we will give a proof for the uniqueness of 4th-order time-reversible sym- plectic difference schemes of 13.h-fold compositions of phase flows φtH(1) , φtH(2) , φtH(3) with different temporal parameter... 详细信息

关键词： Time-Reversible symplectic scheme Splitable hamiltonian.

SYMPLECTIC COMPUTATION OF HAMILTONIAN SYSTEMS (I)

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Journal of Computational Mathematics 2002年第3期20卷 267-276页

作者： Yi-fa Tang(LSEC,ICMSEC,academy of Mathematics and System Sciences, chinese academy of Sciences,Beijing 100080, China) 中科院数学与系统科学院 LSEC ICMSEC CAS 北京 100080

Presents information on a study which discussed a symplectic computation of hamiltonian systems. Terms of formal energy of mid-point rule; Analysis of the mathematical pendulum to test the convergence of the formal en... 详细信息

关键词： mid-point rule formal energy

RT Leonis Minoris:an Unstable W Ursae Majoris System with a Spotted Component

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chinese Journal of Astronomy and Astrophysics 2004年第6期4卷 553-562页

作者： Yu-Lan Yang and Qing-Yao LiuNational Astronomical Observatories, Yunnan Observatory, chinese academy of Sciences,Kunming 650011 United Laboratory of Optical Astronomy, chinese academy of Sciences National Astronomical Observatories Yunnan Observatory Chinese Academy of Sciences Kunming 650011

Complete BV light curves of the W UMa type binary RT LMi are presented. From the observations, four times of minimum light were determined. Based on the new times of minimum light and those collected from the literature, changes in the orbital period of the system were found and analyzed with Kalimeris et al.'s method. The result shows that the orbital period possibly oscillates with a cycle of about 64 years and an amplitude of 1.2 × 10-6 days. The present CCD photometric observations reveal that the light curves are obviously asymmetrical, and show a positive O'Connell effect, while the light curves obtained in 1982 exhibit a negative O'Connell effect. The present light curves were analyzed by means of the latest version of the Wilson-Devinney code, which was also used to correct the photometric effects, including the distortion on the radial-velocity curves obtained by Rucinski et al. The following absolute dimensions have been derived: MI -1.28 ±0.08 M⊙, M2 = 0.48 ±0.06 M⊙, R1 = 1.28 ±0.06 R⊙, R2 = 0.83 ±0.05 R⊙, L1 = 1.88±0.12 L⊙, L2 = 0.77±0.08 L⊙, and A = 2.64±0.02 R⊙. The asymmetry of the light curves can be explained by a model with a cool spot on the secondary component. The orbital period modulation can be reproduced by a magnetic activity cycle model of the secondary component with ΔJ = 5.6 × 1046 g cm2 s-1, ΔΩ/Ω = 8.8 × 10-4, and B = 5.1 × 103 G.

关键词： star: contact binary - star: individuals: RT LMi - star: magnetic activity

CONVERGENCE OF NONLINEAR CONJUGATE GRADIENT METHODS

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Journal of Computational Mathematics 2001年第5期19卷 539-548页

作者： Yu-hong Dai (LSEC, ICMSEC, academy of Mathematics and Systems Sciences, chinese academy of Sciences,Beijing 100080, China) 中科院计算数学与科学工程计算所北京 100080

Presents a study on methods for unconstrained optimization. Assumptions of the study; Main results; Convergence properties of the methods under simplified Armijo-type line search.

关键词： unconstrained optimization conjugate gradient (generalized) line search global convergence

The Kiloparsec-scale Structure of 3C 286

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chinese Journal of Astronomy and Astrophysics 2004年第1期4卷 28-36页

作者： Tao An, Xiao-Yu Hong and Wei-Hua WangShanghai Astronomical Observatory, chinese academy of Sciences, Shanghai 200030 National Astronomical Observatories, chinese academy of Sciences, Beijing 100012 Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 Wyatt Technology Corporation 6300 Hollister Avenue Santa Barbara CA 93117-3253

We present radio images of the compact steep spectrum (CSS) quasar 3C 286 acquired with the Very Large Array (VLA) at 8.4 and 22.5 GHz. The source exhibits a two-sided core-jet structure with a bright central component and two extended components one to the east (P.A. 100°) and another to the southwest (P.A. - 116°). From the compact core, an extension runs towards the southwest component up to - 0.7 arcsecond. The emission between the primary central component and the southwest component exhibits a knotty structure. A gradual change of the jet position angles from -13.° to -120° in the inner southwest jet suggests a local bend. The position angle changes of the major eastern components E2 and El suggest that the eastern jet likely follows a curved trace. The bends in the jet trace may be associated with a relativistic precession or some interaction between the jet and the ambient matter. A mean spectral index of a22.58.4- 0.76 (Xv Va) is estimated for the core component. Steep spectra are also obtained for the extended southwest component (2.6', P.A. -116°) and eastern component (0.8', P.A. 100°), with a22.58.4-0.88 and a22.58.4-1.79, respectively. The radio morphologies and spectral index distributions suggest that the core seen in our images is likely to be the beamed inner jet while the real nucleus is dimmed by it beaming away from us.

关键词： galaxy: quasar: individual - radio continuum: VLA

Transformations and non-degenerate maps

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Science China Mathematics 2005年第z1期48卷 195-205页

作者： LI Baokui & WANG Yuefei Institute of Mathematics, academy of Mathematics and System Sciences, chinese academy of Sciences, Beijing 100080, China Graduate School, chinese academy of Sciences, Beijing 100080, China Institute of Mathematics Academy of Mathematics and System Sciences Chinese Academy of Sciences Beijing China Graduate School Chinese Academy of Sciences Beijing China

We shall prove the equivalences of a non-degenerate circle-preserving map and a M(o)bius transformation in ^Rn, of a non-degenerate geodesic-preserving map and an isometry in Hn of a non-degenerate line-preserving map and an affine transformation in Rn. That a map is non-degenerate means that the image of the whole space under the map is not a circle, or geodesic or line respectively. These results hold without either injective or surjective, or even continuous assumptions, which are new and of a fundamental nature in geometry.

关键词： M(o)bius transformation, circle-preserving map, non-degenerate map.

Expert consensus on radiotherapy combined with immunotherapy for esophageal cancer(2024 edition)

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Radiation Medicine and Protection 2024年第2期5卷 59-67页

作者： Professional Committee of Radiation Oncology China Anti-Cancer Association Branch of Radiation Oncology chinese Medical Association Branch of Radiation Oncology TreatmentPhysician chinese Medical Doctor Association Qingsong Pang Jun Wang Zhouguang Hui Wencheng Zhang 不详 Tianjin Medical University Cancer Institute&Hospital Tianjin 300060China the Fourth Hospital of Hebei Medical University Shijiazhuang 050011China National Cancer Center National Clinical Research Center for CancerCancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100021China Tianjin Medical University Cancer Hospital China

Radiotherapy represents an essential treatment approach for esophageal *** recent years,immunotherapy combined with chemotherapy has become the first-line standard treatment for patients with advanced esophageal *** phase III studies on immunotherapy combined with radiotherapy for locally advanced esophageal cancer are currently *** evidence-based medical data are urgently needed to support the integration of immunotherapy and chemoradiotherapy as a new treatment strategy for patients with locally advanced esophageal *** consensus,formulated based on the latest study results,in-depth research,and thorough discussions,provides a comprehensive set of *** document extensively covers treatment strategies and evaluation methods for radiotherapy combined with immunotherapy across patients with operable esophageal cancer,inoperable locally advanced esophageal cancer,and advanced esophageal ***,common complications and radiation-related issues associated with radiotherapy combined with immunotherapy are discussed,serving as clinical *** expert group comprised members from the Professional Committee of Radiation Oncology,China Anti-Cancer Association,the Branch of Radiation Oncology,chinese Medical Association,and the Branch of Radiation Oncology Treatment Physician,chinese Medical Doctor Association.

关键词： Esophageal squamous cell carcinoma Esophageal adenocarcinoma Immunotherapy Chemoradiotherapy Radiotherapy Expert consensus

A NEW STABILIZED FINITE ELEMENT METHOD FOR SOLVING THE ADVECTION-DIFFUSION EQUATIONS

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Journal of Computational Mathematics 2002年第1期20卷 57-64页

作者： Huo-yuan Duan (Institute of Mathematics, academy of Mathematics and System Sciences, chinese academy of Sciences, Beijing 100080, China) Institute of Mathematics Academy of Mathematics and System Sciences Chinese Academy of Sciences 北京 100080

Focuses on a study on the development of a stabilized finite element method for solving the advection-diffusion equations with a zero Dirichlet boundary condition. Problem formulation; Error analysis.

关键词： advection-diffusion equation stabilized finite element method