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Energy principle and material removal sequence optimization method in machining of aircraft monolithic parts

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Chinese Journal of Aeronautics 2020年第10期33卷 2770-2781页

作者： Yinfei YANG Longxin fan liang LI guolong ZHAO Ning HAN Xiaoyue LI hui TIAN Ning HE College of Mechanical&Electrical Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China AVIC Xi’an Aircraft Industry(Group)Company LTD Xi’an 710089China

In the machining process of aircraft monolithic parts,the initial residual stress redistribution and structural stiffness evolution often lead to unexpected *** the other hand,the stress redistribution and stiffness reduction during the machining process depend on the material removal *** essence of the stress redistribution is releasing the initial elastic strain *** the present study,the influence of the material removal sequence on the energy release is ***,a novel optimization method is proposed for the material removal *** order to evaluate the performance of the proposed method,the mechanism of the machining distortion is firstly analyzed based on the energy *** a calculative model for the machining distortion of long beam parts is established ***,an energy parameter related to the bending distortion and the procedure of the material removal sequence optimization is ***,the bending distortion analysis and material removal sequence optimization are performed on a long beam with a Z-shaped ***,simulation and experiments are carried *** obtained results indicate that the optimized sequence results in a low distortion fluctuation and decreases the bending distortion.

关键词： Aircraft monolithic part Distortion Initial residual stress Material removal sequence Strain energy

Constant modulus sequence set design with low weighted integrated sidelobe level in spectrally crowded environments

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Science China(Information Sciences) 2022年第5期65卷 287-288页

作者： Yi BU hui QIU Tao fan Xianxiang yu guolong CUI Lingjiang KONG School of Information and Communication Engineering University of Electronic Science and Technology of China

Dear editor,Radar waveform design with desired correlation properties has received considerable attention because of its performance improvement in the detection of a weak target [1,2].Moreover, owing to the increasin... 详细信息

关键词： Weighted Integrated Sidelobe Level Finite Alphabet Case Inexact Alternating Direction Penalty Method Spectral Congestion Constant Modulus Sequence Set

Study on forming directivity with constant beam widthin low frequency based on small sensor

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Chinese Journal of Acoustics 2001年第1期20卷 25-29页

作者： hui junying,liu hong,yu huabing,liang guolong (Underwater Acoustic Enyineering Dept. Harbin Engineering University Harbin 150001) Underwater Acoustic Engineering Dept. Harbin Engineering University Harbin 150001

Based on a combined sensor with the size of 10 cm, a narrow beam with a constant receiving beam width of 20 degree has been formed in low frequency from several Hz to thousands of Hz by using simple adaptive algorithm. The results of theoretical simulation, laboratory experiment and lake experiment with one-dimension and two-dimension combined sensors have been given.

关键词： underwater narrow sized sonar detecting dipole distinguish favorable rotating circles

Machining deformation of single-sided component based on finishing allowance optimization

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Chinese Journal of Aeronautics 2020年第9期33卷 2434-2444页

作者： Xiaoyue LI liang LI Yinfei YANG guolong ZHAO Ning HE Xiaocen DING Yaowen SHI Longxin fan hui LAN Muhammad JAMIL National Key Laboratory of Science and Technology on Helicopter Transmission Nanjing University of Aeronautics and AstronauticsNanjing 210016China AVIC Jiangxi hongdu A viation Industry Group Company Ltd Nanchang 330000China

Owing to reliability and high strength-to-weight ratio,large thin-walled components are widely used in the aviation and aerospace *** to the complex features and sequence involved in the machining process of large thin-walled components,machining deformation of component is easy to exceed the *** order to address the problem,it is important to retain the appropriate finishing *** find the overall machining deformation,finishing allowance-induced deformation(web finishing allowance,sidewall finishing allowance)and initial residual stress-induced deformation were considered as major ***,machined surface residual stress-induced deformation,clamping stress-induced deformation,thermal deformation,gravity-induced deformation and inertial force-induced deformation were neglected in the optimization ***-peak Gaussian function was introduced to fit the initial residual *** upon the obtained function of initial residual stress,a deformation prediction model between initial residual stress and finishing allowance was established to attain the finishing allowanceinduced *** addition,linear programming optimization model based on the simplex algorithm was developed to optimize the overall machining *** have concluded that the overall machining deformation reached the minimum value when sidewall finishing allowance and web finishing allowance varied between 1 and 2 ***,web finishing allowance-induced deformation and sidewall finishing allowance-induced deformation were1.05 mm and 0.7 ***,the machining deformation decreased to 0.3–0.38 mm with the application of optimized finishing allowance allocation strategy,which made 39–56%reduction of the overall machining deformation compared to that in conventional method.

关键词： Finishing allowance Linear programming Machining deformation Residual stresses Simplex algorithm

声压振速信息联合处理应用于声场的相干性分析

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哈尔滨工程大学学报 2000年第1期21卷 48-50页

作者：梁国龙余华兵刘宏惠俊英哈尔滨工程大学水声工程系黑龙江哈尔滨150001

声场声压与振速的相干性是声压、振速信息联合处理的重要物理基础之一 ,本文对其进行了初步的分析 .在新型组合传感器湖试的基础上 ,把环境噪声场分解为不相干的各向同性分量和相干的各向异性分量 ,初步分析环境噪声场的构成 ;

关键词：声压振速声场环境噪声水下噪声

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一种汽车智能换挡体系的研究

中国机械工程 2001年第5期12卷 585-588页

作者：葛安林金辉张洪坤范巨新尹华兵吉林大学北京北方车辆研究所

智能换挡是汽车自动变速技术的发展方向。在分析驾驶员—汽车—环境闭环系统各部分之间关系的基础上 ,研究了驾驶员类型、意图、汽车行驶环境与驾驶员操纵特征参数、汽车行驶状态参数之间的关系 ,提出并建立了基于驾驶员操纵推理的汽车... 详细信息

智能换挡是汽车自动变速技术的发展方向。在分析驾驶员—汽车—环境闭环系统各部分之间关系的基础上 ,研究了驾驶员类型、意图、汽车行驶环境与驾驶员操纵特征参数、汽车行驶状态参数之间的关系 ,提出并建立了基于驾驶员操纵推理的汽车智能换挡系统体系结构 ,并进行了转弯过程的汽车智能换挡与通常自动换挡对比实验验证。

关键词：智能换挡驾驶员类型驾驶意图驾驶环境汽车驾驶自动变速器

基于CiteSpace软件的绞股蓝研究文献可视化分析

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井冈山大学学报（自然科学版） 2023年第1期44卷 97-106页

作者：温秀萍蔡煜娟徐惠龙许文范世明徐伟林羽福建中医药大学药学院福建福州350122 福建中医药大学生物医药研发中心福建福州350122

目的分析绞股蓝的研究现状,以发现其研究热点及变化趋势,为今后研究提供参考。方法检索中国知网(CNKI)、万方、维普、中国生物医学文献数据库和Web of science中1991年1月1日至2021年12月31日绞股蓝的相关文献,采用CiteSpace.5.7.R5软... 详细信息

目的分析绞股蓝的研究现状,以发现其研究热点及变化趋势,为今后研究提供参考。方法检索中国知网(CNKI)、万方、维普、中国生物医学文献数据库和Web of science中1991年1月1日至2021年12月31日绞股蓝的相关文献,采用CiteSpace.5.7.R5软件对文献作者、研究机构、关键词等内容构建知识图谱的可视化分析。结果共筛选纳入中文文献2491篇、英文文献510篇。中、英文文献发文量总体呈波浪式上升趋势;研究机构和作者的共现知识图谱显示,研究机构和作者主要集中在各大高校和科研院所;论文发文量最多的作者分别是谭华炳和朴香兰;发文量最多的机构是吉首大学生物资源与环境科学学院和中国科学院,各研究机构间合作较少;高频关键词知识图谱显示“绞股蓝总皂苷”、“绞股蓝皂苷”、“绞股蓝多糖”关键词中心性排在前3位。中英文文献分析显示绞股蓝的研究主要集中在药理作用和临床实验等方面,成分分析、药效物质作用机制、临床应用、开发利用是今后的研究热点。结论目前绞股蓝的研究仍处于发展阶段,科学合作网络分布松散,未来作者、研究机构之间需跨团体、跨区域增强团队间交流合作,为进一步研究提供借鉴。

关键词：绞股蓝文献计量 CiteSpace 知识图谱可视化