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An SOR Implicit Time-accurate Scheme in Calculating Unsteady Flows

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Chinese Journal of Aeronautics 2007年第3期20卷 202-209页

作者： li Yue-jun yan Chao School of Aeronautic Science and Engineering Beijing University of 4eronautics andAstronautics Beijing 100083 China

A new time-accurate marching scheme for unsteady flow calculations is proposed in the present work. This method is the combination of classical Successive Over-Relaxation （SOR） iteration method and Jacobian matrix diagonally dominant splitting method of LUSGS. One advantage of this algorithm is the second-order accuracy because of no factorization error. Another advantage is the low computational cost because the Jacobian matrices and fluxes are only calculated once in each physical time step. And, the SOR algorithm has better convergence property than Gauss-Seidel. To investigate its accuracy and convergency, several unsteady flow computational tests are carded out by using the proposed SOR algorithm. Roe＇s FDS scheme is used to discritize the inviscid flux terms. Unsteady computational results of SOR are compared with the experiment results and those of Gauss-Seidel, Results reveal that the numerical results agree well with the experimental data and the second-order accuracy can be obtained as the Gauss-Seidel for unsteady flow computations. The impact of SOR factor is investigated for unsteady computations by using different SOR factors in this algorithm to simulate each computational test. Different numbers of inner iterations are needed to converge to the same criterion for different SOR factors and optimal choice of SOR factor can improve the computational efficiency greatly.

关键词： unsteady flow SOR algorithm SOR factor Gauss-Seidel

The Continuity of Barrier Function with Respect to the Parameter

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Chinese Annals of Mathematics,Series B 2009年第2期30卷 145-152页

作者： Xinxiang li jun yan School of Mathematical Sciences Fudan University Shanghai 200433 China

The authors study the continuity of barrier function Be（x） with respect to the parameter. A sufficient condition which makes Be（x） be continuous with respect to c is obtained, and an example of discontinuity when ... 详细信息

关键词： Lagrangian systera Average action Barrier function Minimal measure Uniquely ergodic

功能性电刺激联合新Bobath技术在脑卒中后肩痛患者康复中的效果观察

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吉林医学 2025年第1期46卷 20-24页

作者：李燕军蒋雪骏上海市第五康复医院康复医学科上海201600

目的:探讨功能性电刺激联合新Bobath技术在脑卒中后肩痛患者康复中的效果。方法:选取2022~2023年在上海市第五康复医院接受治疗的脑卒中后肩痛患者90例,采用随机数字表法分为试验组(功能性电刺激联合新Bobath技术治疗)和对照组(新Bobat... 详细信息

目的:探讨功能性电刺激联合新Bobath技术在脑卒中后肩痛患者康复中的效果。方法:选取2022~2023年在上海市第五康复医院接受治疗的脑卒中后肩痛患者90例,采用随机数字表法分为试验组(功能性电刺激联合新Bobath技术治疗)和对照组(新Bobath技术治疗)各45例,并比较二者的临床治疗效果、疼痛视觉模拟量表(VAS)评分和运动功能评分量表(Fugl-Meyer)评分、肩关节活动度评分、生活质量评分及患者治疗满意度,探讨其应用价值。结果:试验组治疗总有效率(84.44%)高于对照组(64.44%),差异有统计学意义(P<0.05)。治疗4周后,试验组VAS评分低于治疗前和对照组,Fugl-Meyer评分高于治疗前和对照组,差异均有统计学意义(P<0.05)。治疗4周后,试验组肩关节屈曲、外展、外旋的活动度均大于对照组,差异均有统计学意义(P<0.05)。治疗4周后,两组生活质量评分均高于治疗前,且试验组高于对照组,差异均有统计学意义(P<0.05)。试验组总满意度均高于对照组,差异有统计学意义(P<0.05)。结论:功能性电刺激联合新Bobath技术在脑卒中后肩痛患者康复中的效果较好,治疗后患者满意度较高。

关键词：功能性电刺激新Bobath技术脑卒中肩关节痛康复

Calibration of line structured light vision system based on camera’s projective center

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光学精密工程 2005年第5期13卷 584-591页

作者： ZHU Ji-gui li yan-jun YE Sheng-hua State Key Laboratory of Precision Measuring Technology and Instrument Tianjin Universality Tianjin 300072China

Based on the characteristics of line structured light sensor, a speedy method for the calibration was established. With the coplanar reference target, the spacial pose between camera and optical plane can be calibrated by using of the camera’s projective center and the light’s information in the camera’s image surface. Without striction to the movement of the coplanar reference target and assistant adjustment equipment, this calibration method can be implemented. This method has been used and decreased the cost of calibration equipment, simplified the calibration procedure, improved calibration efficiency. Using experiment, the sensor can attain relative accuracy about 0.5%, which indicates the rationality and effectivity of this method.

关键词：投影中心线性结构光传感器标度可视性系统

Radar target recognition based on micro-Doppler effect

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Optoelectronics Letters 2008年第6期4卷 456-459页

作者： DONG Wei-guang li yan-jun College of Astronautics Northwestern Polytechnical University Xi ＇an 710072 China

Mechanical vibration of target structures will modulate the phase function of radar backscattering,and will induce the frequency modulation of returned signals from the target. It generates a side bands of the target body Doppler frequency shift,which is helpful for target recognition. Based on this,a micro-Doppler atomic storehouse is built for the target recognition,and four kinds of common classifiers are used separately to perform the classified recognition. The simulation experimental results show that this method has high recognition rate above 90%.

关键词：雷达目标显微多普勒效应信息处理后向散射

Synthesis and Crystal Structure of a New Mononuclear Copper(Ⅱ) Complex with 4,4′,6,6′-Tetrabromo-2,2′- [ethylenedioxybis(nitrilomethylidyne)]diphenol

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Chinese Journal of Structural Chemistry 2008年第2期27卷 183-186页

作者： XU li ZHANG Yah-Ping WANG li SHI jun-yan DONG Wen-Kui School of Chemical and Biological Engineering Lanzhou Jiaotong University Lanzhou Gansu 730070 China

A new mononuclear Cu（II） complex, [Cu（L）] （H2L = 4,4′,6,6v-tetrabromo-2,2′- [ethylenedioxybis（nitrilomethylidyne）]diphenol）, has been synthesized and structurally characterized. X-ray crystal structure of the complex reveals that the Cu（Ⅱ） ion is four-coordinated by two oxygen atoms and two nitrogen atoms from L2- unit. Crystallographic data： monoclinic, space group P21/n with a = 14.076（2）, b = 6.9801（14）, c = 19.858 （2） A, β= 107.613（2）°, C16n10Br4CuN2O4, Mr = 677.44, V = 1859.6（5） A3, Dc = 2.420 g/cm3,μ = 9.796 mm^-1, F（000） = 1284, Z = 4, the final R = 0.0516 and wR = 0.0938 for 1879 observed reflections with I 〉 2σ（/）. The dihedral angel between the two coordination planes of Cu（1）-N（2）--O（4） and Cu（1 ）-N（ 1 ）-O（3）） is 30.08（6）°.

关键词： 4,4′,6,6′-tetrabromo-2,2′-[ethylenedioxybis(nitrilomethylidyne)]diphenol,copper(li) complex synthesis crystal structure

500 kV高压线下地铁车站围护结构技术研究与应用

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工程建设与设计 2025年第3期 95-97页

作者：李彦君赵浩然焉兆熙中交路桥建设有限公司重庆404100 中南大学资源与安全工程学院长沙410083

随着城市轨道交通的快速发展,高压线下地铁车站的施工已成为一个备受关注的难题。高压线会对地铁车站的施工造成一系列的困难。论文以重庆市某轨道交通车站工程为例,分析了500 kV高压线下地铁车站施工中遇到的问题,并提出了相应的围护... 详细信息

随着城市轨道交通的快速发展,高压线下地铁车站的施工已成为一个备受关注的难题。高压线会对地铁车站的施工造成一系列的困难。论文以重庆市某轨道交通车站工程为例,分析了500 kV高压线下地铁车站施工中遇到的问题,并提出了相应的围护结构方案选比。

关键词： 500 kV高压线地铁车站围护结构施工技术

Novel chiral thioureas for highly enantioselective Michael reactions of malonates to nitroalkenes

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Chinese Chemical Letters 2009年第3期20卷 310-313页

作者： li jun yan Quan Zhong liu Xue lian Wang Laboratory of Applied Chemistry and Pollution Control Technology College of Chemistry and Chemical Engineering China West Normal University Nanchong 637002 China

Highly efficient Michael addition reactions of malonates to nitroalkenes catalyzed by novel chiral thioureas derived from optically pure BINOL and amino acids are reported. Various trans-nitroalkenes reacted with malo... 详细信息

关键词： Michael addition Thiourea Enantioselectivities Nitroalkene and malonate

The optimal time-frequency atom search based on a modified ant colony algorithm

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Optoelectronics Letters 2008年第3期4卷 227-230页

作者： GUO jun-feng li yan-jun YU Rui-xing ZHANG Ke College of Astronautics Northwestern Polytechnical University Xi＇ an 710072China

this paper, a new optimal time-frequency atom search method based on a modified ant colony algorithm is proposed to improve the precision of the traditional methods. First, the discretization formula of finite length time-frequency atom is inferred at length. Second; a modified ant colony algorithm in continuous space is proposed. Finally, the optimal time- frequency atom search algorithm based on the modified ant colony algorithm is described in detail and the simulation experiment is carried on. The result indicates that the developed algorithm is valid and stable, and the precision of the method is higher than that of the traditional method.

关键词：最优化频率原子计算方法