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Error Analysis of MSAV Scheme for Two Phase Magnetohydrodynamic Diffuse Interface Model
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作者 HU Kun WANG Danxia +1 位作者 ZHANG Jianwen JIA Hongen 《应用数学》 北大核心 2025年第2期348-371,共24页
In this paper,we develop a multi-scalar auxiliary variables(MSAV)scheme for the Cahn-Hilliard Magnetohydrodynamics system by introducing two scalar auxiliary variables(SAV).This scheme is linear,fully decoupled and un... In this paper,we develop a multi-scalar auxiliary variables(MSAV)scheme for the Cahn-Hilliard Magnetohydrodynamics system by introducing two scalar auxiliary variables(SAV).This scheme is linear,fully decoupled and unconditionally stable in energy.Subsequently,we provide a detailed implementation procedure for full decoupling.Thus,at each time step,only a series of linear differential equations with constant coefficients need to be solved.To validate the effectiveness of our approach,we conduct an error analysis for this first-order scheme.Finally,some numerical experiments are provided to verify the energy dissipation of the system and the convergence of the proposed approach. 展开更多
关键词 Cahn-Hilliard Magnetohydrodynamics system Fully decoupled Stability in energy error analysis
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DEVELOPMENT AND ERROR ANALYSIS OF AN INSPECTING SYSTEM FOR MEASURING THE ROTATIONAL INERTIA OF BULLETS 被引量:15
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作者 车英 李占国 +3 位作者 陈礼华 白素平 马宏 韩文波 《兵工学报》 EI CAS CSCD 北大核心 2000年第1期-,共3页
介绍了一种用于测量弹丸转动惯量的高精度测量仪器,该仪器利用双悬丝扭摆机构、光电计时系统提取摆动周期信息,由MCS-51系列单片机组成的测量系统进行数据处理,并由LED显示器测量结果。文中阐述了仪器的工作原理, 推导了所需的计算... 介绍了一种用于测量弹丸转动惯量的高精度测量仪器,该仪器利用双悬丝扭摆机构、光电计时系统提取摆动周期信息,由MCS-51系列单片机组成的测量系统进行数据处理,并由LED显示器测量结果。文中阐述了仪器的工作原理, 推导了所需的计算公式,分析了产生测量误差的因素,进行了定量精度分析,给出了实验结果与测量精度。 展开更多
关键词 转动惯量 摆动周期 测量误差 DEVELOPMENT AND error analysis of AN INSPECTING
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Analysis and modeling of error of spiral bevel gear grinder based on multi-body system theory 被引量:4
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作者 陈书涵 严宏志 明兴祖 《Journal of Central South University of Technology》 EI 2008年第5期706-711,共6页
Six-axis numerical control spiral bevel gear grinder was taken as the object, multi-body system theory and Denavit-Hartenberg homogeneous transformed matrix (HTM) were utilized to establish the grinder synthesis err... Six-axis numerical control spiral bevel gear grinder was taken as the object, multi-body system theory and Denavit-Hartenberg homogeneous transformed matrix (HTM) were utilized to establish the grinder synthesis error model, and the validity of model was confirmed by the experiment. Additionally, in grinding wheel tool point coordinate system, the errors of six degrees of freedom were simulated when the grinding wheel revolving around C-axis, moving along X-axis and Y-axis. The influence of these six errors on teeth space, helix angle, pitch, teeth profile was discussed. The simulation results show that the angle error is in the range from -0.148 4 tad to -0.241 9 rad when grinding wheel moving along X, Y-axis; the translation error is in the range from 0.866 0 μm to 3.605 3μm when grinding wheel moving along X-axis. These angle and translation errors have a great influence on the helix angle, pitch, teeth thickness and tooth socket. 展开更多
关键词 six-axis GRINDER spiral bevel gear error model analysis
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3-D fracture network dynamic simulation based on error analysis in rock mass of dam foundation 被引量:5
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作者 ZHONG Deng-hua WU Han +2 位作者 WU Bin-ping ZHANG Yi-chi YUE Pan 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第4期919-935,共17页
Accurate 3-D fracture network model for rock mass in dam foundation is of vital importance for stability,grouting and seepage analysis of dam foundation.With the aim of reducing deviation between fracture network mode... Accurate 3-D fracture network model for rock mass in dam foundation is of vital importance for stability,grouting and seepage analysis of dam foundation.With the aim of reducing deviation between fracture network model and measured data,a 3-D fracture network dynamic modeling method based on error analysis was proposed.Firstly,errors of four fracture volume density estimation methods(proposed by ODA,KULATILAKE,MAULDON,and SONG)and that of four fracture size estimation methods(proposed by EINSTEIN,SONG and TONON)were respectively compared,and the optimal methods were determined.Additionally,error index representing the deviation between fracture network model and measured data was established with integrated use of fractal dimension and relative absolute error(RAE).On this basis,the downhill simplex method was used to build the dynamic modeling method,which takes the minimum of error index as objective function and dynamically adjusts the fracture density and size parameters to correct the error index.Finally,the 3-D fracture network model could be obtained which meets the requirements.The proposed method was applied for 3-D fractures simulation in Miao Wei hydropower project in China for feasibility verification and the error index reduced from 2.618 to 0.337. 展开更多
关键词 rock mass of dam foundation 3-D fracture network dynamic simulation fractal dimension error analysis relative absolute error(RAE) downhill simplex method
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Opto-mechanical-thermal integration analysis of Doppler asymmetric spatial heterodyne interferometer
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作者 WANG Jin-jiang JIANG Lun +3 位作者 TONG Shou-feng PEI Hui-yi CUI Yong GUO Ming-hang 《中国光学(中英文)》 EI CAS CSCD 北大核心 2024年第6期1489-1511,共23页
In order to improve the detection accuracy of Doppler asymmetric spatial heterodyne(DASH)interferometer in harsh temperatures,an opto-mechanical-thermal integration analysis is carried out.Firstly,the correlation betw... In order to improve the detection accuracy of Doppler asymmetric spatial heterodyne(DASH)interferometer in harsh temperatures,an opto-mechanical-thermal integration analysis is carried out.Firstly,the correlation between the interference phase and temperature is established according to the working principle and the phase algorithm of the interferometer.Secondly,the optical mechanical thermal analysis model and thermal deformation data acquisition model are designed.The deformation data of the interference module and the imaging optical system at different temperatures are given by temperature load simulation analysis,and the phase error caused by thermal deformation is obtained by fitting.Finally,based on the wind speed error caused by thermal deformation of each component,a reasonable temperature control scheme is proposed.The results show that the interference module occupies the main cause,the temperature must be controlled within(20±0.05)℃,and the temperature control should be carried out for the temperature sensitive parts,and the wind speed error caused by the part is 3.8 m/s.The thermal drift between the magnification of the imaging optical system and the thermal drift of the relative position between the imaging optical system and the detector should occupy the secondary cause,which should be controlled within(20±2)℃,and the wind speed error caused by the part is 3.05 m/s.In summary,the wind measurement error caused by interference module,imaging optical system,and the relative position between the imaging optical system and the detector can be controlled within 6.85 m/s.The analysis and temperature control schemes presented in this paper can provide theoretical basis for DASH interferometer engineering applications. 展开更多
关键词 Doppler asymmetric spatial heterodyne interferometer interference module imaging optical system opto-mechanical thermal integration analysis phase error temperature control
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Development of analysis model for geometric error in turning processes 被引量:1
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作者 LEE Mun-jae LEE Choon-man 《Journal of Central South University》 SCIE EI CAS 2011年第3期711-717,共7页
A finite element model was established for analyzing the geometric errors in turning operations and a two-step analyzing process was proposed. In the first analyzing step, the cutting force and the cutting heat for th... A finite element model was established for analyzing the geometric errors in turning operations and a two-step analyzing process was proposed. In the first analyzing step, the cutting force and the cutting heat for the cutting conditions were obtained using the AdvantEdge. Also, the deformation of a workpiece was estimated in the second step using the ANSYS. The deformation was analyzed for a 150 mm-long workpiece at three different measuring points, such as 10, 70 and 130 mm from a reference point, and the amounts of the deformation were compared through experiments. /n the results of the comparison and analysis, the values obtained from these comparison and analysis represent similar tendencies. Also, it is verified that their geometric errors increase with the increase in temperature. In addition, regarding the factors that affect the deformation of a workpiecc, it can be seen that the geometric error in the lathe is about 15%, the error caused by the cutting force is about 10%, and the deformation caused by the heat is about 75%. 展开更多
关键词 geometric error machining accuracy finite element analysis TURNING cutting force cutting temperature
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静态法测定WF6-MoF6体系汽液相平衡数据的误差分析与修正
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作者 拓振光 李荣亮 +7 位作者 康绍辉 牛玉清 周志全 叶开凯 马海桃 刘顺 李洪 高鑫 《化工学报》 北大核心 2025年第5期2270-2278,共9页
核纯级氟化铀及相关氟化物杂质的汽液相平衡数据缺乏,已成为我国干法铀纯化转化工艺开发的瓶颈。然而,该体系物性的复杂性与特殊性给数据的准确测定带来了极大困难。为此设计并研制了一种高压耐腐蚀静态法汽液相平衡测量装置,测定了纯组... 核纯级氟化铀及相关氟化物杂质的汽液相平衡数据缺乏,已成为我国干法铀纯化转化工艺开发的瓶颈。然而,该体系物性的复杂性与特殊性给数据的准确测定带来了极大困难。为此设计并研制了一种高压耐腐蚀静态法汽液相平衡测量装置,测定了纯组分VF_(5)和MoF_(6)的饱和蒸气压数据以及WF_(6)和MoF_(6)二元体系在不同温度下的恒温汽液相平衡数据。重点从装置设计、操作过程和分析检测三个角度进行了全面的误差分析与数据校正,结果表明气相取样对液相组成的影响不足万分之五;原料组成视为液相组成存在约0.5%的误差;降低气相取样吹扫气速和减小升温速率会减少误差等。基于误差分析与估算结果对实验数据进行修正后,通过了热力学一致性检验,为准确获取金属氟化物汽液相平衡热力学数据提供了支撑。 展开更多
关键词 汽液平衡 二元混合物 氟化物 静态法 误差分析
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Some of Advances on the Error Analysis in the Frequency Domain for a Digital Simulation Model
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作者 Fei, Jinggao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1994年第3期2-19,共18页
This paper surveys a number of recent advances in the error analysis in the frequency domain for a digital simulation model. It is emphasized to discuss the errors in characteristic roots and transfer funcnon of the d... This paper surveys a number of recent advances in the error analysis in the frequency domain for a digital simulation model. It is emphasized to discuss the errors in characteristic roots and transfer funcnon of the digital simulation model, the frequency domain errors of the data transfers between thesimulation submodels, and some compensation methods for the errors. Some of the questions to be answered are also presented. 展开更多
关键词 Digital simulation MODEL Frequency domain error analysis.
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Hyperbolic Error Analysis and Parametric Optimization of Round Body Form Tool
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作者 ZHENG You-yi 1, LI Xing 1, ZHAO Lai-fu 2, GAO Ai-hua 1 (1. Jiaozuo Institute of Technology, Jiaozuo 454000, China 2. China United Telecommunication Corporation Jiaozuo Branch, Jiaozuo 454000, China) 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期63-,共1页
with the merits of the easy manufacture and the long service life and the processing the inside or outside form surface, round body form tool is extensive use in large scales production. Its main demerit is the big hy... with the merits of the easy manufacture and the long service life and the processing the inside or outside form surface, round body form tool is extensive use in large scales production. Its main demerit is the big hyperbolic error which is caused in the process of processing cone, but about the discussion of hyperbolic error, there are two drawbacks in the current books and documents: (1) The error measuring plane is established on the rake face of tool, which doesn’t coincide with the actual measuring plane (axial plane) of work piece; (2) When the influential elements of error are analyzed, single parameter is only discussed. In order to overcome these demerits, the mathematical model of hyperbolic error on the axial plane of work piece is built in this paper when round body form tool processes cone. The fundamental reason which causes hyperbolic error when round body form tool processes cone is that the line profile replaces the curve profile of theory in the radial cut plane of tool in the design and manufacture of tool. In order to evaluate the mathematical formula of its error, firstly, the equation of cone of work piece must be established, secondly, the equation of cutting lip in the rake face is established, then, the profile equation of the radial plane of tool is evaluated on the condition that coordinate is changed, at last, the hyperbolic error is derived according to the equation and the substitutional line equation, and the error is converted to the axial plane of work piece which is coincided with the measuring plane. The actual calculation and the theory analysis indicated that if the cone length and the coning of the cone of work piece are fixed, the main elements which affect the hyperbolic error in the axial plane of work piece are the outside diameter R of round body form tool, the rake angle and the rear angle in "base point". If these three parameters are combined rationally, the hyperbolic error is minimum when round body form tool process cone, and the machining precision of work piece can be improved, on the condition that neither the work capacity of the tool design nor the manufacture cost of tool increases. 展开更多
关键词 round body form tool analysis of hyperbolic error parametric optimization
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Resolution performance analysis of cumulants-based rank reduction estimator in presence of unexpected modeling errors
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作者 王鼎 吴瑛 《Journal of Central South University》 SCIE EI CAS 2013年第11期3116-3130,共15页
Compared to the rank reduction estimator (RARE) based on second-order statistics (called SOS-RARE), the RARE employing fourth-order cumulants (referred to as FOC-RARE) is capable of dealing with more sources and... Compared to the rank reduction estimator (RARE) based on second-order statistics (called SOS-RARE), the RARE employing fourth-order cumulants (referred to as FOC-RARE) is capable of dealing with more sources and mitigating the negative influences of the Gaussian colored noise. However, in the presence of unexpected modeling errors, the resolution behavior of the FOC-RARE also deteriorate significantly as SOS-RARE, even for a known array covariance matrix. For this reason, the angle resolution capability of the FOC-RARE was theoretically analyzed. Firstly, the explicit formula for the mathematical expectation of the FOC-RARE spatial spectrum was derived through the second-order perturbation analysis method. Then, with the assumption that the unexpected modeling errors were drawn from complex circular Gaussian distribution, the theoretical formulas for the angle resolution probability of the FOC-RARE were presented. Numerical experiments validate our analytical results and demonstrate that the FOC-RARE has higher robustness to the unexpected modeling en'ors than that of the SOS-RARE from the resolution point of view. 展开更多
关键词 performance analysis rank reduction estimator (RARE) fourth-order cumulants (FOC) spatial spectrum angle resolution probability unexpected modeling errors
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Error Analysis in Foreign Language Teaching 被引量:1
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作者 薛俊梅 《陕西师范大学学报(哲学社会科学版)》 CSSCI 北大核心 1999年第S1期105-108,共4页
CLCnumber:H319Documentcode:AArticleID:1000-5293(1999)Sup.-0106-04Allanguageteachersandlearnersareawarethatle... CLCnumber:H319Documentcode:AArticleID:1000-5293(1999)Sup.-0106-04Allanguageteachersandlearnersareawarethatlearnersmakemistake... 展开更多
关键词 ENGLISH learning FOREIGN LANGUAGE TEACHING error analysis
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The Scientific Error Analysis在工程计算中的应用
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作者 汪超 《机床与液压》 北大核心 2005年第4期171-171,184,共2页
介绍了TheScientificErrorAnalysis软件包的使用以及基于该软件包的误差分析的原理, 给出了工程计算实例。该软件包编程容易, 结果正确, 值得在工程误差分析中推广应用。
关键词 MAPLE 工程计算 误差分析
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Error Analysis in Frequency Domain for Linear Multipass Algorithms
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作者 费景高 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2001年第4期77-84,共8页
Error analysis methods in frequency domain are developed in this paper for determining the characteristic root and transfer function errors when the linear multipass algorithms are used to solve linear differential eq... Error analysis methods in frequency domain are developed in this paper for determining the characteristic root and transfer function errors when the linear multipass algorithms are used to solve linear differential equations. The relation between the local truncation error in time domain and the error in frequency domain is established, which is the basis for developing the error estimation methods. The error estimation methods for the digital simulation model constructed by using the Runge-Kutta algorithms and the linear multistep predictor-corrector algorithms are also given. 展开更多
关键词 ALGORITHMS Computer simulation Differential equations error analysis Frequency domain analysis Runge Kutta methods
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Study of a New Method of Tracking Control with Zero Steady-State Error on Very-Low Frequency
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作者 肖卫国 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2001年第4期66-70,共5页
A servo control system is prone to low speed and unsteadiness during very-low-frequency follow-up. A design method of feedforward control based on intelligent controller is put foward. Simulation and test results show... A servo control system is prone to low speed and unsteadiness during very-low-frequency follow-up. A design method of feedforward control based on intelligent controller is put foward. Simulation and test results show that the method has excellent control characteristics and strong robustness, which meets the servo control needs with very-low frequency. 展开更多
关键词 Computer simulation error analysis Intelligent control Robustness (control systems)
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蛇形空间机械臂单个2-DOF关节的运动学标定 被引量:1
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作者 宋国庆 赵成浩 +2 位作者 袁俊杰 张忠海 何广平 《机床与液压》 北大核心 2024年第3期1-9,共9页
绳索驱动的分段式蛇形空间机械臂通常具有相同结构的模块化关节,能够在狭小空间中灵巧操作,其精度是制约机器人发展的主要因素。为了提高蛇形空间机械臂的位置精度,指导蛇形空间机械臂的精度设计,以单个2-DOF关节为对象,提出一种正则化... 绳索驱动的分段式蛇形空间机械臂通常具有相同结构的模块化关节,能够在狭小空间中灵巧操作,其精度是制约机器人发展的主要因素。为了提高蛇形空间机械臂的位置精度,指导蛇形空间机械臂的精度设计,以单个2-DOF关节为对象,提出一种正则化的运动学标定方法。首先,对具有多重映射关系的2-DOF关节的运动学进行分析,通过矩阵全微分理论建立包含所有几何误差参数的误差模型。然后,对2-DOF关节各部件的所有误差源进行灵敏度分析,依据3σ原则和理想的位置精度设计指标指导各部件的公差设计。最后,考虑所有的制造和装配误差,采用正则化方法对2-DOF关节进行误差辨识,用于补偿控制器中的名义运动学模型。结果表明,经过修正后的运动学模型的位置精度提高了50%,验证了运动学标定的有效性。 展开更多
关键词 运动学 误差分析 灵敏度分析 运动学标定 精度设计
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Complex geometric modeling and tooth contact analysis of a helical face gear pair with arc-tooth
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作者 MO Shuai SONG Wen-hao +3 位作者 ZHU Sheng-ping FENG Zhi-you TANG Wen-jie GAO Han-jun 《Journal of Central South University》 SCIE EI CAS CSCD 2022年第4期1213-1225,共13页
A complex geometric modeling method of a helical face gear pair with arc-tooth generated by an arc-profile cutting(APC)disc is proposed,and its tooth contact characteristics are analyzed.Firstly,the spatial coordinate... A complex geometric modeling method of a helical face gear pair with arc-tooth generated by an arc-profile cutting(APC)disc is proposed,and its tooth contact characteristics are analyzed.Firstly,the spatial coordinate system of an APC face gear pair is established based on meshing theory.Combining the coordinate transformation matrix and the tooth profile of the cutter,the equations of the curve envelope of the APC face gear pair are obtained.Then the surface equations are solved to extract the point clouds data by programming in MATLAB,which contains the work surface and the fillet surface of the APC face gear pair.And the complex geometric model of the APC face gear pair is built by fitting its point clouds.At last,through the analysis of the tooth surface contact,the sensitivity of the APC face gear to the different types of mounting errors is obtained.The results show that the APC face gear pair is the most sensitive to mounting errors in the tooth thickness direction,and it should be strictly controlled in the actual application. 展开更多
关键词 arc-tooth face gear complex geometric modeling point clouds mounting errors tooth contact analysis
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基于Web of Science的巩膜镜研究态势文献计量分析
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作者 徐浩 周万里 +2 位作者 翟晶 李旖旎 郭迎暄 《中华实验眼科杂志》 CAS CSCD 北大核心 2024年第2期152-158,共7页
目的通过文献计量方法分析Web of Science数据库中巩膜镜的研究现状。方法检索2013年1月至2022年12月Web of Science核心合集数据库收录的巩膜镜相关文献,采用CiteSpace工具对文献进行可视化分析,对文献发文量、国家及机构分布、核心作... 目的通过文献计量方法分析Web of Science数据库中巩膜镜的研究现状。方法检索2013年1月至2022年12月Web of Science核心合集数据库收录的巩膜镜相关文献,采用CiteSpace工具对文献进行可视化分析,对文献发文量、国家及机构分布、核心作者信息、刊文期刊分布及关键词聚类等方面进行综合分析。结果共检索到340篇文献,相关文献分别刊载在54种期刊,平均每种期刊约6.3篇,涉及301位作者;该研究领域覆盖35个国家或地区,共256个研究机构;学科发展主要集中在美国、印度、西班牙、澳大利亚,主要研究领域为巩膜镜(巩膜接触镜)、眼表疾病、角膜水肿、小型巩膜接触镜等方面。近10年来,巩膜镜的研究热点变化趋势为从最初的巩膜接触镜与眼表疾病相结合的研究,到后续的眼表人工置换研究,再到角膜间隙及形状方面的研究。2013—2021年主要关注的主题为眼表疾病、巩膜接触镜及角膜水肿,而在2021年后,眼表疾病和角膜移植术的相关研究有衰落趋势。2013年1月至2022年12月巩膜镜相关的突现词主要包括:第1阶段为巩膜接触镜、移植、抗宿主病、假体装置等研究;第2阶段为眼表生态系统人工置换、不规则角膜等研究;第3阶段为角膜间隙、特有形状等研究。光学相干断层扫描和角膜地形图是巩膜镜研究和验配的常用检查。结论目前巩膜镜主要应用于干眼、角膜扩张、角膜炎、角膜移植(特别是穿透角膜移植术后)和屈光不正;眼表人工置换、角膜间隙及形状是近年的研究热点。 展开更多
关键词 干眼 角膜疾病 角膜移植 屈光不正 巩膜镜 文献计量学 CiteSpace 综合分析
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面齿轮蜗杆砂轮磨削安装误差分析及补偿
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作者 李国龙 蒲峙杉 +3 位作者 何坤 王梓宇 宁行 张薇 《计算机集成制造系统》 北大核心 2025年第2期452-463,共12页
为了提高面齿轮的磨削加工精度,提出一种齿面误差补偿方法。基于普通蜗杆砂轮磨齿机的机械结构,分析其磨削原理,规划砂轮磨削运动轨迹,并分别建立含刀具同轴度误差和工件平面度误差的面齿轮齿面模型,分析各自对齿面误差的影响规律;提出... 为了提高面齿轮的磨削加工精度,提出一种齿面误差补偿方法。基于普通蜗杆砂轮磨齿机的机械结构,分析其磨削原理,规划砂轮磨削运动轨迹,并分别建立含刀具同轴度误差和工件平面度误差的面齿轮齿面模型,分析各自对齿面误差的影响规律;提出一种基于自适应完备集合经验模态分解的随机误差分离方法,消除齿面测量结果中的随机误差;研究齿面误差分布情况,分析可能造成误差的原因,并依据齿面误差影响规律对机床参数进行修正,以实现误差补偿。最后完成磨齿和测量,结果表明齿面最大法向误差减小79.8%,最大齿形和齿向误差分别减小67.6%和72.4%,齿面精度提高显著。 展开更多
关键词 面齿轮 蜗杆砂轮磨削 误差分析 误差分离 误差补偿
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基于核主成分分析的半监督日志异常检测模型 被引量:2
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作者 顾兆军 叶经纬 +2 位作者 刘春波 张智凯 王志 《江苏大学学报(自然科学版)》 CAS 北大核心 2025年第1期64-72,97,共10页
对于具有“组异常”和“局部异常”分布特点的系统日志数据,传统的ADOA(anomaly detection with partially observed anomalies)半监督日志异常检测方法存在为无标签数据生成的伪标签准确性不佳的问题.针对此问题,提出一种改进的半监督... 对于具有“组异常”和“局部异常”分布特点的系统日志数据,传统的ADOA(anomaly detection with partially observed anomalies)半监督日志异常检测方法存在为无标签数据生成的伪标签准确性不佳的问题.针对此问题,提出一种改进的半监督日志异常检测模型.对已知异常样本采用k均值聚类,采用核主成分分析计算无标签样本的重构误差;运用重构误差和异常样本相似分计算出样本的综合异常分,作为其伪标签;依据伪标签计算LightGBM分类器的样本权重,训练异常检测模型.通过参数试验探究了训练集样本比例变化对模型性能的影响.在HDFS和BGL这2个公开数据集上进行试验,结果表明该模型能够提高伪标签的准确性,相较于DeepLog、LogAnomaly、LogCluster、PCA和PLELog等已有模型,精确率和F 1分数均有提升.与传统的ADOA异常检测方法相比,该模型F 1分数在2类数据集上分别提高了0.084和0.085. 展开更多
关键词 系统日志 日志异常检测 组异常 局部异常 半监督 重构误差 核主成分分析 伪标签
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日本周边海域及西北太平洋重力数据分析
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作者 孔敏 刘玉龙 +2 位作者 王风帆 余佳 李维禄 《大地测量与地球动力学》 北大核心 2025年第6期640-648,共9页
收集日本在其周边海域及西北太平洋通过船载调查获取的227个航次海洋重力数据集,应用统计分析法、可视成图法、相关分析法等开展日本重力调查情况及数据质量情况分析,系统分析日本重力数据调查历史、时空分布特征及质量情况。结果显示,... 收集日本在其周边海域及西北太平洋通过船载调查获取的227个航次海洋重力数据集,应用统计分析法、可视成图法、相关分析法等开展日本重力调查情况及数据质量情况分析,系统分析日本重力数据调查历史、时空分布特征及质量情况。结果显示,船测重力数据与GEBCO地形数据、DTU重力模型数据具有良好的空间一致性,其中与DTU模型的相关系数为0.98,均方根误差为7.7 mGal。本文建立了航迹交点差值模型,并利用交点差误差进行数据测量精度的定量分析,总交点共73979个,误差为11.85 mGal,内部交点24822个,误差为9.56 mGal,外部交点49157个,误差为12.85 mGal,数据测量准确度总体较高,数据一致性较好。 展开更多
关键词 海洋重力 质量分析 交点差 日本周边海域
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