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All-Solid-State Near-Infrared and Blue Femtosecond Laser System

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Chinese Physics Letters 2002年第2期19卷 203-204页

作者： Bai jin-tao, Chen Guo-fu Institute of Photonics & Photo-technology Northwest University Provincial Key Laboratory of Photoelectronic Technology Northwest University State Key Laboratory of Transient Optics and Technology Xi"an Institute of Optics and Precision Mechanics Chi

We investigate an all-solid-state continuous wave (cw) green (532 nm), femtosecond near-infrared (823.1 nm) and blue (402 nm) laser system which is pumped by a diode-laser-pumped intracavity frequency-doubled and all-self-structuring cw Nd:YVO4/KTP 532 nm green laser. The cavity parameters of the Nd:YVO4/KTP laser have been optimized and the maximum 5.6 W TEM00 green laser is obtained at a 22 W pump power with an optical-optical conversion efficiency of 25.5%. A Ti:Sapphire laser and nonlinear second-harmonic generation by a crystal BBO is used to obtain different wavelengths. A femtosecond laser with an average output power of 300 mW at 823.1 nm and 73 mW at 402 nm is obtained when the green pump power is 2.5 W. The spectral full width at half maximum are 32.3 nm and 5.1 nm, which can sustain the pulses of 22 fs and 33.3 fs, respectively

关键词： Femtosecond lasers

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某室外景观钢拱桥设计

工程建设与设计 2018年第23期 102-104页

作者：陶劲夫陈柯成都基准方中建筑设计有限公司成都610017

某室外小区景观桥采用钢拱桥结构形式,拱桥跨度约为11m。采用Midas GEN进行建模、设计和截面校核,分别进行了强度验算、刚度验算以及舒适度验算。针对拱形结构会产生跳跃失稳问题,采用ABAQUS进行了特征值屈曲分析和非线性屈曲分析(材料... 详细信息

某室外小区景观桥采用钢拱桥结构形式,拱桥跨度约为11m。采用Midas GEN进行建模、设计和截面校核,分别进行了强度验算、刚度验算以及舒适度验算。针对拱形结构会产生跳跃失稳问题,采用ABAQUS进行了特征值屈曲分析和非线性屈曲分析(材料非线性和几何非线性)。针对拱形结构水平推力大的问题,进行了桩基抗水平力、抗倾覆验算。通过计算分析,该钢拱桥满足规范的强度、刚度、舒适度、稳定性、地基承载力要求。

关键词：钢拱桥特征值屈曲非线性屈曲桩基水平承载力

IAU2000和后IAU2000岁差-章动模型中岁差量的二历元表达式

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天文学报 2005年第1期46卷 27-36页

作者：任树林陶金河傅燕宁中国科学院紫金山天文台南京210008

IAU第24届大会决议从2003年起采用IAU 2000岁差-章动模型. IERS 规范(2003)给出了上述岁差-章动模型中7个常用岁差量的单历元表达式; 2003年, Capitaine等对上述模型进行了改进,改进后的新模型称为后IAU 2000(post IAU 2000) 岁差-章动... 详细信息

IAU第24届大会决议从2003年起采用IAU 2000岁差-章动模型. IERS 规范(2003)给出了上述岁差-章动模型中7个常用岁差量的单历元表达式; 2003年, Capitaine等对上述模型进行了改进,改进后的新模型称为后IAU 2000(post IAU 2000) 岁差-章动模型.在此基础上,分别得到了上述两种岁差-章动模型中相关岁差量的二历元表达式.应用到坐标变换中,该两种表达式与原模型的精度相当,在1800到2200年的时间范围内,分别达到-1毫角秒和-1微角秒.由于除展开阶数外所给出的岁差量表达式与IAU 1976岁差模型具有相同的形式,因此为实际应用提供了便利.结果已用于中国天文年历的编算.

关键词：岁差单历元年历精度坐标变换天文表达式阶数差模

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7.63m特大型焦炉砌筑施工技术及要点

安徽建筑工业学院学报（自然科学版） 2010年第1期18卷 30-34页

作者：陶金福伍昌国中国十七冶炉窑工程技术公司马鞍山243000

主要针对7.63m特大型焦炉砌筑施工技术,从工程实践效果分析其施工技术在质量、工期、成本等方面收到良好的经济效益和社会效益,现对7.63m特大型焦炉施工技术作简要介绍。

关键词： 7.63m特大型焦炉砌筑施工技术及要点

Reducing the measurement errors in nonadiabatic holonomic quantum computers

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 64-70页

作者： Guo-fu Xu Department of Physics Shandong University

Nonadiabatic holonomic quantum computers serve as the physical platform for nonadiabatic holonomic quantum *** quantum computation has entered the noisy intermediate-scale era, building accurate intermediate-scale nonadiabatic holonomic quantum computers is clearly necessary. Given that measurements are the sole means of extracting information, they play an indispensable role in nonadiabatic holonomic quantum computers. Accordingly, developing methods to reduce measurement errors in nonadiabatic holonomic quantum computers is of great importance. However, while much attention has been given to the research on nonadiabatic holonomic gates, the research on reducing measurement errors in nonadiabatic holonomic quantum computers is severely lacking. In this study, we propose a measurement error reduction method tailored for intermediate-scale nonadiabatic holonomic quantum computers. The reason we say this is because our method can not only reduce the measurement errors in the computer but also be useful in mitigating errors originating from nonadiabatic holonomic gates. Given these features,our method significantly advances the construction of accurate intermediate-scale nonadiabatic holonomic quantum computers.

关键词： quantum holonomy quantum computation measurement errors

红细胞分布宽度与老年非ST段抬高急性冠状动脉综合征的关系

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中国卫生检验杂志 2016年第23期26卷 3398-3400页

作者：李涛金先富刘志国浙江省台州医院心血管内科浙江台州317000 浙江省台州医院检验科浙江台州317000

目的探讨红细胞分布宽度（RDW）与老年非ST段抬高急性冠状动脉综合征（NSTE-ACS）的关系。方法选取老年NSTE-ACS患者和健康体检者各120例,分析RDW、主要临床及生化指标在老年NSTE-ACS患者中的变化。应用ROC曲线对RDW诊断NSTE-ACS效率进... 详细信息

目的探讨红细胞分布宽度（RDW）与老年非ST段抬高急性冠状动脉综合征（NSTE-ACS）的关系。方法选取老年NSTE-ACS患者和健康体检者各120例,分析RDW、主要临床及生化指标在老年NSTE-ACS患者中的变化。应用ROC曲线对RDW诊断NSTE-ACS效率进行分析,并确定RDW对预后判断的界值以评估RDW与远期不良事件的关系。结果老年NSTE-ACS患者组高血压患病率、LDL-C水平、WBC、RDW和NLR水平均高于对照组,经Logistic回归分析显示,高血压、LDL-C、RDW和NLR均为NSTE-ACS的独立危险因素。ROC曲线显示RDW的曲线下面积为0.651（95%CI：0.582~0.720）,且RDW〉13.45%时,远期心血管不良事件发生率较高。结论 RDW是老年NSTE-ACS的独立危险因素,且RDW与老年NSTE-ACS患者的远期不良事件发生有关。

关键词：红细胞分布宽度老年非ST段抬高急性冠状动脉综合征远期不良事件

Stability of the axial-auto-balanced impeller of centrifugal pump

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Journal of Hydrodynamics 2022年第4期34卷 665-680页

作者： Fa-ye jin Ran tao Di Zhu Ruo-fu Xiao College of Water Resources and Civil Engineering China Agricultural UniversityBeijing 100083China Beijing Engineering Research Center of Safety and Energy Saving Technology for Water Supply Network System Beijing 100083China College of Engineering China Agricultural UniversityBeijing 100083China

The pump is one of the most important energy consuming devices in an energy system. The axial force on a centrifugal pump is an important factor for improving the operation stability and the service life. Based on the Bernoulli’s equation, the formulas of the axial clearance are derived theoretically. The relationship between the impeller axial force, the clearance leakage flow rate and the axial clearance is obtained. The motion differential equation of the axial-auto-balanced impeller is established by the number axis modeling method. The asymptotic stability of the impeller is evaluated by the Lyapunov stability analysis. The transient simulation of the axial-auto-balanced impeller is carried out by the method of the computational fluid dynamics (CFD) with the dynamic mesh technology. The time required for the impeller to reach the stable state under different conditions is calculated. The effective values of the axial force are determined. This research is useful to improve the operation stability of the pump.

关键词： Canned motor pump impeller axial force auto-balanced impeller Lyapunov stability analysis

Successive Partial-Symmetric Rank-One Algorithms for Almost Unitarily Decomposable Conjugate Partial-Symmetric Tensors

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Journal of the Operations Research Society of China 2019年第1期7卷 147-167页

作者： tao-Ran fu jin-Yan Fan School of Mathematical Sciences Shanghai Jiao Tong UniversityShanghai 200240China School of Mathematical Sciences and MOE-LSCShanghai Jiao Tong UniversityShanghai 200240China

In this paper,we introduce the almost unitarily decomposable conjugate partial-symmetric tensors,which are different from the commonly studied orthogonally decomposable tensors by involving the conjugate terms in the decomposition and the perturbation *** not only show that successive rank-one approximation algorithm exactly recovers the unitary decomposition of the unitarily decomposable conjugate partial-symmetric *** perturbation analysis of successive rank-one approximation algorithm for almost unitarily decomposable conjugate partial-symmetric tensors is also provided to demonstrate the robustness of the algorithm.

关键词： Approximation algorithm Complex tensor Perturbation analysis

A bio-inspired optical imaging method for robotic perception in turbid water

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Science China Technological Sciences 2025年第1期 79-81页

作者： Xudong SUN Yafeng LI Peng LIN Xiaodi SHANG Xianping fu School of Information Science and Technology Dalian Maritime University College of Computer Science and Technology Qingdao University

In the realm of underwater robotics, optical imaging plays a pivotal role in many scientific researches. Due to the effects of absorption and scattering,images captured in turbid water are severely degraded. Therefore, enhancing the quality of underwater optical images stands paramount in ensuring the continued advancement and efficacy of underwater robots across its multifarious applications.

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