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An initial study on left ventricular diastolic function in patients with hypertrophy cardiomyopathy using single-beat, real-time, three-dimensional echocardiography

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Journal of Geriatric Cardiology 2012年第3期9卷 220-227页

作者： Bei zhao Juan Li Yong Xu hong-Wei Zhu guang Zhi Department of Cardiology Chinese PLA General Hospital28 Fuxing Road100853 BeijingChina

Objectives To assess the regional diastolic function in patients with hypertrophic cardiomyopathy （HCM） by using single-beat, real-time, three-dimensional echocardiography （RT-3DE）. Methods Sixty-five patients with HCM in sinus rhythm together with fifty age- and gender-matched normal controls were studied by two dimensional echocardiography （2DE） and RT-3DE. The parameters analyzed by RT-3DE included： left ventrieular （LV） volumes, left ventricular ejection fraction （LVEF）, end diastolic sphericity index （EDSI）, diastolic dyssynchrony index （DDI）, dispersion end diastole （DISPED）, and normalized 17 segmental volume-time curves. Results Evaluated by RT-3DE, LVEF was slightly lower compared with 2DE （63.2 ± 6.8% vs. 59.1 ± 6.4%, P 〈 0.0001）. Normal subjects had relatively uniform volumetric curves for all LV segments. In HCM patients, the segmental volumetric curves were dyssynchronous. Increased DDI and DISPED in end diastole were observed in patients with HCM （9.95 ± 3.75, 41.76 ± 17.19, P 〈 0.0001）, and not all abnormal volumetric segments occurred in the hypertrophic regions. Conclusions Patients with HCM have presented regional diastolic dyssynchrony in the diastole phase, and this preclinical lesion can be recognized by single-beat RT-3DE.

关键词： Echocardiography Hypertrophic cardiomyopathy Diastolic dyssynchrony

PLS-CCA Heterogeneous Features Fusion-based Low-resolution Human Detection Method for Outdoor Video Surveillance

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International Journal of Automation and computing 2017年第2期14卷 136-146页

作者： hong-Kai Chen Xiao-guang zhao Shi-Ying Sun Min Tan State Key Laboratory of Management and Control for Complex Systems Institute of Automation Chinese Academy of Sciences Beijing 100190 China

In this paper, we focus on low-resolution human detection and propose a partial least squares-canonical correlation analysis （PLS-CCA） for outdoor video surveillance. The analysis relies on heterogeneous features fusion-based human detection method. The proposed method can not only explore the relation between two individual heterogeneous features as much as possible, but also can robustly describe the visual appearance of humans with complementary information. Compared with some other methods, the experimental results show that the proposed method is effective and has a high accuracy, precision, recall rate and area under curve （AUC） value at the same time, and offers a discriminative and stable recognition performance.

关键词： Low-resolution human detection partial least squares canonical correlation analysis heterogeneous features outdoorvideo surveillance.

Ground-state phase diagram of the dimerizedspin-1/2 two-leg ladder

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Chinese Physics B 2021年第8期30卷 496-501页

作者： Cong Fu Hui zhao Yu-guang Chen Yong-hong Yan School of Physics Science and Engineering Tongji UniversityShanghai 200092China School of Mathematical Information Shaoxing UniversityShaoxing 312000China

Dimerized spin-1/2 ladders exhibit a variety of phase structures,which depend on the intra-chain and inter-chain spin exchange energies as well as on the dimerization pattern of the *** the density matrix renormalization group(DMRG)algorithm,we study critical properties of the bond-alternating two-leg Heisenberg spin ladder with diagonal interaction J_(×).Two types of spin systems,staggered dimerized antiferromagnetic ladder and columnar dimerized ferro-antiferromagnetic couplings ladder,are *** clarify the phase transition behaviors,we simultaneously analyze the string order parameter(SOP),the twisted order parameter(TOP),as well as a measurement of the quantum information *** on measuring this different observables,we establish the phase diagram accurately and give the fitting functions of the phase *** addition,the phase transition of cross-coupled spin ladder(in the absence of intrinsic dimerization)is also discussed.

关键词： spin ladder density matrix renormalization group Heisenberg model quantum phase transition

Numerical Simulation and Experimental Study on Interlock Deformation for Roll Formed U-Section Steel Piling

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Journal of Iron and Steel Research International 2013年第11期20卷 41-45页

作者： FENG guang-hong ZHANG Pei ZHANG hong-liang ZHOU Xu-chang zhao Yong Metallurgical Technology Institute Central Iron and Steel Research Institute Taian Kenuo Profile Steel Co. Ltd.

The interlock of a roll formed U-section sheet steel piling under loading was analyzed by means of numeri- cal simulation, and meanwhile the tensile failure experiment was conducted. The results indicated that under the same load, the interlock corners of roll formed steel piling are not only the regions with the lowest safety factor, but also the regions with the highest stress; there are two slippages in the tensile instability process of interlock, Each slippage can be regarded as a failure, and different types of failure mode should be used to evaluate the performance of steel pilings according to different applications. Due to the work hardening effect during the roll forming process, the hardness of the interlock material increases by 16% compared with that of the original sheet steel. It was also found that the instability strength obtained in tensile failure test is only 15.6 % of the tensile strength of the original sheet steel.

关键词： roll formed sheet steel piling interlock numerical simulation instability

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模型间歇振荡器的混沌特性分析

系统仿真学报 2005年第1期17卷 249-251页

作者：马红光韩崇昭孔祥玉王国华朱小菲许剑锋西安交通大学电信学院西安710049 第二炮兵工程学院101教研室陕西西安710025

建立了雷达发射机中的间歇振荡器的非线性数学模型,利用相空间图、功率谱分析法、平均位移法和Lyapunov指数对该模型仿真产生的时间序列和实测信号进行了分析,理论和实验结果表明,间歇振荡器所产生的高频脉冲序列具有混沌特性,所推导的... 详细信息

建立了雷达发射机中的间歇振荡器的非线性数学模型,利用相空间图、功率谱分析法、平均位移法和Lyapunov指数对该模型仿真产生的时间序列和实测信号进行了分析,理论和实验结果表明,间歇振荡器所产生的高频脉冲序列具有混沌特性,所推导的数学模型和分析结果具有普适性。

关键词：间歇振荡器混沌时间序列相空间 Lyapunov指数

Fully Actuated System Approach for 6DOF Spacecraft Control Based on Extended State Observer

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Journal of Systems Science & Complexity 2022年第2期35卷 604-622页

作者： zhao Qin DUAN guang-Ren Center for Control Science and Technology Southern University of Science and TechnologyShenzhen 518055China Center for Control Theory and Guidance Technology Harbin Institute of TechnologyHarbin 150001China

This paper deals with the problem of position and attitude tracking control for a rigid spacecraft.A fully actuated system(FAS)model for the six degree-of-freedom(6DOF)spacecraft motion is derived first from the state-space model by variable *** the uncertainties from external disturbance,unknown motion information,and uncertain inertia properties,an extended state observer(ESO)is designed to estimate the total ***,a tracking controller based on FAS approach is designed,and this makes the closed-loop system a constant linear one with an arbitrarily assignable *** solution to the parameter matrices of the observer and controller is given *** is proved via the Lyapunov stability theory that the observer errors and tracking errors both converge into the neighborhood of the ***,numerical simulation demonstrates the effectiveness of the proposed controller.

关键词： Constant linear closed-loop system extended state observer fully actuated system approach relative position and attitude control

New Feedback Control Model in the Lattice Hydrodynamic Model Considering the Historic Optimal Velocity Difference Effect

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Communications in Theoretical Physics 2018年第12期69卷 803-807页

作者： guang-Han Peng Shu-hong Yang hong-Zhuan zhao College of Physics and Electronics Hunan University of Arts and Science College of Physical Science and Technology Guangxi Normal University School of Computer Science and Communication Engineering Guangxi University of Science and Technology College of Architecture and Transportation Engineering Guilin University of Electronic Technology

A feedback control model of lattice hydrodynamic model is proposed by taking the information of the historic optimal velocity into account for the traffic system. The modern control theory is applied for the linear stability condition with feedback control signal. The result shows that the stability of traffic flow is closely related to the information of the historic optimal velocity. Furthermore, numerical simulations conform that the new feedback control did increase the stability of traffic flow efficiently, which is in accord with theoretical analysis.

关键词： traffic flow lattice hydrodynamic model control method traffic jam

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利脉胶囊对小鼠学习记忆的影响

咸宁学院学报（医学版） 2008年第4期22卷 279-281页

作者：王帮华陈红光赵骥郑敏武汉大学基础医学院湖北武汉430071 咸宁学院中心实验室

目的观察利脉胶囊对东莨菪碱致小鼠学习记忆障碍及正常小鼠空间学习记忆的影响。方法采用跳台实验观察利脉胶囊(140mg/kg ig qd×14)对东莨菪碱所致小鼠学习记忆障碍的改善作用,以触电潜伏期及单位时间内错误次数作为学习记忆成绩;采用M... 详细信息

目的观察利脉胶囊对东莨菪碱致小鼠学习记忆障碍及正常小鼠空间学习记忆的影响。方法采用跳台实验观察利脉胶囊(140mg/kg ig qd×14)对东莨菪碱所致小鼠学习记忆障碍的改善作用,以触电潜伏期及单位时间内错误次数作为学习记忆成绩;采用Morris水迷宫实验观察利脉胶囊(140mg/kg,ig qd×20)对正常小鼠空间学习记忆的影响,以定位航行实验小鼠逃避潜伏期及空间探索实验小鼠经过目标平台次数作为学习记忆成绩。结果①跳台试验。第1d跳台训练,利脉胶囊组3m in内跳台错误次数少于模型组(P0.05)。第2d跳台检测,东莨菪碱模型组触电潜伏期较正常对照组明显缩短;利脉胶囊治疗组触电潜伏期显著长于模型组(P<0.01),而与正常对照组接近,5m in错误次数有减少趋势。②水迷宫试验。利脉胶囊治疗组逃避潜伏期小于正常组,经过目标平台次数有增加趋势。结论利脉胶囊对东莨菪碱所致小鼠学习记忆障碍有一定的改善作用,并具有一定的促智作用。

关键词：利脉胶囊东莨菪碱跳台实验学习记忆 Morris水迷宫实验

Effect of Al22Si/ZL102 bimetal interface fabricated by extrusion at neareutectic temperature

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Journal of Iron and Steel Research International 2017年第4期24卷 469-474页

作者： Jun-feng zhao Shan-guang Liu Xiao-guang Yuan Jian-fei Sun hong-jun Huang Fu-yang Cao hong-xian Shen Yu-long Wang School of Materials Science and Engineering Shenyang University of TechnologyShenyang 110178LiaoningChina Beijing Institute of Aeronautical Materials Beijing 100095China School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001HeilongjiangChina

The Al22Si/ZL102 bimetal was designed and prepared by extrusion at near-eutectic *** properties and fracture behaviors of different surface treatments between oxide film and zinc coating were compared between the Al22 Si and ZL102 *** average bonding strength of bimetal with intermittent oxide film interface was about 89.3MPa,which is higher than that of the bimetal fabricated by zinc coating method（about 76.3MPa）.During the process of extrusion,the oxidation film was extruded to crush and the metal was extruded through the micro-cracks of the oxidation film,then the two surfaces were joined ***,the results showed that extrusion at near-eutectic temperature is favorable for achieving a high-quality metallurgical bonded interface.

关键词： Bimetal Oxide film Interface bonding strength Zinc coating