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Analytical Solutions for an Isotropic Elastic Half-Plane with Complete Surface Effects Subjected to a Concentrated/Uniform Surface Load

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Acta Mechanica Solida Sinica 2024年第3期37卷 371-384页

作者： Xia-Hui pan School of Civil Engineering Henan Polytechnic UniversityJiaozuo454003China

Within the context of Gurtin-Murdoch surface elasticity theory,closed-form analytical solutions are derived for an isotropic elastic half-plane subjected to a concentrated/uniform surface *** the effects of residual surface stress and surface elasticity are *** stress function method and Fourier integral transform technique are *** solutions are provided in a compact manner that can easily reduce to special situations that take into account either one surface effect or none at *** results indicate that surface effects generally lower the stress levels and smooth the deformation profiles in the *** elasticity plays a dominant role in the in-plane elastic fields for a tangentially loaded half-plane,while the effect of residual surface stress is fundamentally crucial for the out-of-plane stress and displacement when the half-plane is normally *** the remaining situations,combined effects of surface elasticity and residual surface stress should be *** results for a concentrated surface force serve essentially as fundamental solutions of the Flamant and the half-plane Cerruti problems with surface *** solutions presented in this work may be helpful for understanding the contact behaviors between solids at the nanoscale.

关键词： Surface effects Residual surface stress Surface elasticity Half-plane Analytical solutions

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国家语言能力建设视角下的个人多语能力

语言文字应用 2018年第1期 2-11页

作者：戴曼纯潘巍巍北京外国语大学中国语言文学学院北京100089 北京语言大学外国语学部北京100083

个人多语能力是一个值得探讨的理论概念。本文尝试从国家语言能力建设角度阐述个人发展多语能力的必然性及个人多语能力的构成,并根据语言的使用领域、社会分工和需求将个人多语能力发展分为三个层级。第一层级的多语能力满足一般大众... 详细信息

个人多语能力是一个值得探讨的理论概念。本文尝试从国家语言能力建设角度阐述个人发展多语能力的必然性及个人多语能力的构成,并根据语言的使用领域、社会分工和需求将个人多语能力发展分为三个层级。第一层级的多语能力满足一般大众的家庭和个人发展需求,第二层级增强国家语言能力基础建设,第三层级促进国家语言竞争力的提升。本文认为,个人多语能力不是理想化的同质语言能力,而是动态发展的模块系统,通常具有非平衡性和层级性。

关键词：国家语言能力个人多语能力语言多样性跨语言驾驭能力

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超快拉曼光纤激光器技术研究进展

中国激光 2019年第5期46卷 204-218页

作者：潘伟巍周佳琦张磊冯衍中国科学院上海光学精密机械研究所高功率光纤激光技术实验室上海201800 上海频准激光科技有限公司上海201800 中国科学院大学材料与光电研究中心北京100049

锁模和超短脉冲同步抽运是拉曼光纤激光器得到超短脉冲的主要方式。在锁模拉曼光纤激光器中,基于等效可饱和吸收体的结构可以实现较高性能的输出,但目前仍面临增益光纤过长带来的问题。超短脉冲同步抽运的方式可以有效解决这一问题,实... 详细信息

锁模和超短脉冲同步抽运是拉曼光纤激光器得到超短脉冲的主要方式。在锁模拉曼光纤激光器中,基于等效可饱和吸收体的结构可以实现较高性能的输出,但目前仍面临增益光纤过长带来的问题。超短脉冲同步抽运的方式可以有效解决这一问题,实现参数极佳的超快拉曼激光输出。超快拉曼光纤激光器发展潜力巨大,未来的研究将着眼于进一步提升各类超快拉曼光纤激光器的整体输出性能并探究其中的新现象。

关键词：非线性光学拉曼光纤激光器超快激光锁模同步抽运

Uncertainty Principles on Clifford Modules

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Acta Mathematica Sinica,English Series 2024年第10期40卷 2537-2570页

作者： pan LIAN School of Mathematical Sciences Tianjin Normal University

In this paper, we derive the optimal Cauchy–Schwarz inequalities on a class of Hilbert and Krein modules over a Clifford algebra, which heavily depend on the Clifford algebraic *** obtained inequalities further lead to very general uncertainty inequalities on these modules. Some new phenomena arise, due to the non-commutative nature, the Clifford-valued inner products and the Krein geometry. Taking into account applications, special attention is given to the Dirac operator and the Howe dual pair Pin(m) × osp(1|2). Moreover, it is surprisingly to find that the recent highly nontrivial uncertainty relation for triple observables is indeed a direct consequence of our Cauchy–Schwarz inequality. This new observation leads to refined uncertainty relations in terms of the Wigner–Yanase–Dyson skew information for mixed states and other generalizations. These show that the obtained uncertainty inequalities on Clifford modules can be considered as new uncertainty relations for multiple observables.

关键词： 30G35 81P45 Clifford algebra Fischer decomposition Krein space uncertainty principle Wigner–Yanase–Dyson skew information

非综合征型颅缝早闭症术后矫形头盔治疗45例病例系列报告

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中国循证儿科杂志 2023年第1期18卷 62-65页

作者：潘维伟童笑梅北京大学第三医院儿科北京100191

背景颅缝早闭手术后的矫形效果依赖于头盔矫形治疗。目的探讨非综合征型颅缝早闭术后患儿使用矫形头盔继续治疗的效果。设计病例系列报告。方法回顾性分析2019年1月至2021年12月北京大学第三医院儿童健康发展中心通过矫形头盔继续纠正... 详细信息

背景颅缝早闭手术后的矫形效果依赖于头盔矫形治疗。目的探讨非综合征型颅缝早闭术后患儿使用矫形头盔继续治疗的效果。设计病例系列报告。方法回顾性分析2019年1月至2021年12月北京大学第三医院儿童健康发展中心通过矫形头盔继续纠正治疗的非综合征型颅缝早闭术后患儿的临床资料。主要结局指标头围、头颅不对称指数(CVAI)和头颅比率(CR)。结果45例非综合征型颅缝早闭术后矫形头盔治疗患儿纳入分析,男24例,女21例。冠状缝早闭16例,矢状缝早闭18例,人字缝早闭9例,额缝早闭2例;佩戴矫形头盔前诊断斜头异常15例,短头异常6例,舟状头异常16例,不对称短头异常5例,正常颅形3例。12例行微创颅骨缝合术,33例行开颅颅骨重塑术,中位手术年龄8.5(6,12)月龄。开始佩戴矫形头盔中位时间为术后20(14,26)d,中位佩戴时间7(4.5,10)月。45例患儿均能按照要求佩戴矫形头盔,中位随访时间7.5(5,10.5)月。45例患儿佩戴矫形头盔前和结束佩戴后2周头围[(445±10.5)mm vs(469±6.5)mm]、斜头异常患儿CVAI[(6.1±2.5)vs(3.1±1.2)]、短头异常患儿CR[(0.95±0.08)vs(0.82±0.06)]和舟状头异常患儿CR[(0.72±0.02)vs(0.79±0.03)]均有明显改善。41例于12~24月龄完成神经运动心理发育评分,平均(97.9±7.5)分,均在正常范围。均未出现皮肤溃疡坏死、严重皮疹、皮肤过敏等并发症。结论非综合征型颅缝早闭术后矫形头盔治疗颅形异常的效果肯定,不会造成头颅生长受限,安全性好。

关键词：颅缝早闭矫形头盔婴儿

Aeroengine thrust estimation and embedded verification based on improved temporal convolutional network

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Chinese Journal of Aeronautics 2024年第1期37卷 106-117页

作者： Wanzhi MENG Zhuorui pan Sixin WEN pan QIN Ximing SUN Key Laboratory of Intelligent Control and Optimization for Industrial Equipment of Ministry of Education Dalian University of TechnologyDalian 116024China School of Control Science and Engineering Dalian University of TechnologyDalian 116024China

Thrust estimation is a significant part of aeroengine thrust control *** traditional estimation methods are either low in accuracy or large in *** further improve the estimation effect,a thrust estimator based on Multi-layer Residual Temporal Convolutional Network(M-RTCN)is *** solve the problem of dead Rectified Linear Unit(ReLU),the proposed method uses the Gaussian Error Linear Unit(GELU)activation function instead of ReLU in residual *** the overall architecture of the multi-layer convolutional network is adjusted by using residual connections,so that the network thrust estimation effect and memory consumption are further ***,the comparison with seven other methods shows that the proposed method has the advantages of higher estimation accuracy and faster convergence ***,six neural network models are deployed in the embedded controller of the micro-turbojet *** Hardware-in-the-Loop(HIL)testing results demonstrate the superiority of M-RTCN in terms of estimation accuracy,memory occupation and running ***,an ignition verification is conducted to confirm the expected thrust estimation and real-time performance.

关键词： Thrust estimation Temporal convolutional network Embedded deployment Hardware-in-the-loop testing Ignition verification

Shape optimisation of basin insulator for DC gas insulated switchgear/gas insulated transmission lines based on artificial bee colony algorithm

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High Voltage 2024年第2期9卷 275-286页

作者： Yi Luo Shiyi Mao Ju Tang Zijun pan Cheng pan State Key Laboratory of Power Grid Environmental Protection School of Electrical Engineering and AutomationWuhan UniversityWuhanChina

The surface charge accumulation on the basin insulator is a particular problem in high-voltage direct current(HVDC)gas insulated switchgears(GIS)and gas insulated trans-mission lines(GIL),which restricts the development and application of extra/ultra high-voltage(EHV/UHV)*** surface charge distribution and anti-flashover performance are closely related to the insulator *** obtain the optimal basin insulator,a shape optimisation model based on artificial bee colony algorithm was established,and the minimisation objective functions based on capacitive(initial)electric field distribution and resistive(steady-state)electric field distribution were respectively *** optimisation results of the two objective functions were calculated,and the electric field and charge distribution on the surface of the insulator before and after optimisation were evaluated and compared using the simulation *** results indicated that the optimisation based on the capacitive electric field can significantly inhibit the surface charge accumulation,and the optimised insulator can significantly reduce the surface normal electric field and make the distribution of the tangential electric field more uniform,and the maximum tangential electric field can be reduced by 10%;the optimisation based on resistive electric field can achieve similar results,but requires more computational *** on the results,the‘anti-charge’basin insulator structure suitable for the DC field was given.

关键词： insulator artificial charge

基于关键节点与关键路径的专利集群网络演进研究

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科技进步与对策 2020年第12期37卷 1-8页

作者：潘微微菅利荣刘涛南京航空航天大学经济与管理学院江苏南京211106 中国电子科技集团公司第五十五研究所江苏南京210016

专利作为技术和知识的重要载体,是研究技术演进和产业发展的重要信息源。目前缺乏针对专利集群网络中关键节点与关键路径中节点的比较分析和技术知识挖掘。构建基于关键节点和关键路径的专利集群网络演进模型,从两个层面综合分析技术演... 详细信息

专利作为技术和知识的重要载体,是研究技术演进和产业发展的重要信息源。目前缺乏针对专利集群网络中关键节点与关键路径中节点的比较分析和技术知识挖掘。构建基于关键节点和关键路径的专利集群网络演进模型,从两个层面综合分析技术演进特征。检索德温特数据库(Derwent Innovation Index)得到碳化硅肖特基势垒二极管(SiC-SBD)相关专利作为实证数据,时间跨度为1986-2017年。结果表明,SiC-SBD专利集群网络经历了萌芽期、成长期、成熟期和衰退期,其中,萌芽期专利主要涉及基础技术,成长期为器件结构,以完善器件结构、改进二极管性能为主要研究方向。近年来SiC-SBD专利年增长率下降,技术发展速度放缓,专利价值更多体现在其商业价值上。SiC-SBD专利集群网络关键节点与关键路径中节点重合度较高,核心专利识别可通过多视角分析得到。通过关键节点与关键路径分析专利集群网络演进过程,有助于更全面呈现技术演进过程,为决策者识别核心专利、预测技术发展提供参考。

关键词：专利集群网络技术演进中介中心性关键路径分析

New opportunities for ferroelectric deep-UV nonlinear optical crystals

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Science China Materials 2024年第3期67卷 1004-1005页

作者： Miriding Mutailipu Shilie pan Research Center for Crystal Materials Xinjiang Technical Institute of Physics and ChemistryChinese Academy of SciencesUrumqi 830011China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

Deep-ultraviolet(deep-UV)light with the wavelength below200 nm is one of the most crucial elements of both laser-driven industrial and scientific applications in recent years[1].DeepUV light has been produced using a variety of techniques,such as gas discharge lamps,synchrotron radiation,excimer lasers,free electron lasers,and nonlinear frequency conversion.

关键词： nonlinear optical ferroelectric