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改良鼻中隔成形术60例疗效分析

临床耳鼻咽喉头颈外科杂志 2018年第24期32卷 1890-1892页

作者：周毅波颜永毅于锋广州市第十二人民医院耳鼻咽喉头颈外科、广州市耳鼻咽喉头颈外科医院、广州医科大学耳鼻咽喉头颈外科研究所广州510620

目的:探讨改良鼻中隔成形术治疗鼻中隔偏曲患者的临床疗效及手术技巧。方法:回顾性分析60例接受鼻中隔手术患者的病例特征、手术方式、术后并发症以及手术前后VAS评分及鼻阻力值。结果:28例单纯行改良鼻中隔成形术患者术后VAS评分较术... 详细信息

目的:探讨改良鼻中隔成形术治疗鼻中隔偏曲患者的临床疗效及手术技巧。方法:回顾性分析60例接受鼻中隔手术患者的病例特征、手术方式、术后并发症以及手术前后VAS评分及鼻阻力值。结果:28例单纯行改良鼻中隔成形术患者术后VAS评分较术前明显降低,差异有统计学意义(P<0.01)。患者术后的偏曲侧鼻阻力与总鼻阻力较术前都有明显降低,差异有统计学意义(P<0.01或P<0.05)。结论:改良鼻中隔成形术是治疗鼻中隔偏曲患者的安全、有效的手术方法,值得临床推广。

关键词：鼻中隔鼻阻力鼻中隔成形术

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真空磁浮组合材料管道梁结构设计

真空科学与技术学报 2021年第2期41卷 145-151页

作者：杨国静颜永逸宋晓东中铁二院工程集团有限责任公司成都610031

针对现有钢结构真空管道梁造价高、运输条件受限且安装不便等问题,本文探讨了一种适用于未来长距离运输和车辆条件的组合材料管道梁结构,开展了三种常用跨度管道梁结构的试设计,分析了一联多跨方案对结构刚度和变形的影响。获得研究成果... 详细信息

针对现有钢结构真空管道梁造价高、运输条件受限且安装不便等问题,本文探讨了一种适用于未来长距离运输和车辆条件的组合材料管道梁结构,开展了三种常用跨度管道梁结构的试设计,分析了一联多跨方案对结构刚度和变形的影响。获得研究成果:①分层设计方案可充分发挥结构各自特点,降低施工和运输难度;②通过试设计获得了常用跨度管道梁的关键参数取值,并以某试验线为例,分析了合理跨度选取的各项因素,获得最优经济跨度;③一联多跨方案比选表明联长和跨数的增加可有效提高结构的横、竖向刚度,减小活载变形,对于提升结构运营性能、减少养护工作量有直接作用,但是随着联长的逐渐增加,结构的刚度提升效果将逐渐保持不变;④联长的增加会显著加大纵向温度变形,对轨道结构受力影响较大。研究成果可为真空磁浮高架桥梁的设计提供参考。

关键词：真空高速磁浮管道组合材料高架桥结构设计

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基于物联网的地铁隧道断面监测系统的设计

现代电子技术 2018年第18期41卷 182-186页

作者：曾熙鸿李富年颜永逸武汉科技大学信息科学与工程学院湖北武汉430081 华中科技大学土木工程与力学院湖北武汉430074

为了满足地铁隧道安全信息监测的需要,设计一种远程地铁隧道断面监测与预警系统。系统主要由分布在隧道断面上的监测点和云服务器监控中心两部分组成。监测点以CC2530芯片为核心,使用智能倾角传感器采集断面倾角变化数据,并结合Zig Bee... 详细信息

为了满足地铁隧道安全信息监测的需要,设计一种远程地铁隧道断面监测与预警系统。系统主要由分布在隧道断面上的监测点和云服务器监控中心两部分组成。监测点以CC2530芯片为核心,使用智能倾角传感器采集断面倾角变化数据,并结合Zig Bee无线传感技术和GPRS通信技术将数据上传至云服务器监控中心。通过定制通信协议实现倾角数据的收发存储和查询功能。实践证明,系统结构稳定可靠,具有一定的先进性和推广性,为准确预测地铁隧道的安全情况提供参考。

关键词：地铁隧道断面监测 ZigBee GPRS 云服务器 CC2530

国际合作视野下中国教育双重转型的问题与对策

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语言教育 2019年第1期 2-7页

作者：严永怡广东外语外贸大学

社会文明模式的变迁要求教育模式作出相应的转型。我国教育的现代性转型可以通过学习西方发达国家和地区的现代性教育模式、深化教育的国际合作来实现;后现代教育转型没有成型的模式可资借鉴。教育的现代性转型要求从传统的专重知识型... 详细信息

社会文明模式的变迁要求教育模式作出相应的转型。我国教育的现代性转型可以通过学习西方发达国家和地区的现代性教育模式、深化教育的国际合作来实现;后现代教育转型没有成型的模式可资借鉴。教育的现代性转型要求从传统的专重知识型向知识和技能并重转变,培养学生的自主学习能力等;后现代教育虽尚无成型的模式,但充分利用新媒体、信息技术,培养学生的审美意识和能力,契合互联网+、文化+特征,是目前可以确定的转型特点和方向。

关键词：教育模式教育转型双重转型国际合作创新能力

Towards Data-Driving Multi-View Evaluation Framework for Scratch

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Tsinghua Science and Technology 2024年第2期29卷 517-528页

作者： Xiaolin Chai yan Sun yan Gao Department of Computer Science Beijing University of Posts and TelecommunicationBeijing 100876China Intellectual Property Institute Shandong Polytechnic CollegeJining 272067China

As one of the most popular visual programming languages,Scratch has a lot of evaluation around *** evaluation can help programmers understand their projects *** the same time,it can also provide a reference for them to browse other projects in the online *** of the existing evaluations on Scratch are carried from three perspectives:Computational Thinking(CT)ability,visual presentation aesthetics,and code *** them,the assessment of CT and code quality is mainly carried out from the program script,while the evaluation of visual aesthetics is analyzed from the perspective of image sequences generated by project *** single-view evaluation focuses on the performance of a program in a certain aspect and is *** this paper,we propose a multi-view evaluation framework to integrate various evaluations using different *** quantitatively analyze the assessment of different views driven by *** with overall evaluations that represent human opinions,we analyze their differences and *** experiments,we determine the weights of different integration policies,the proposed multi-view evaluation method can generate evaluation results similar to human opinions.

关键词： Scratch Computational Thinking(CT) visual aesthetic static analysis integration policy machine learning

Forward to the Special Topic on“Solving Differential Equations with Deep Learning”

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Journal of Systems Science & Complexity 2024年第2期37卷 389-390页

作者： yan Zhenya Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing 100190China

The concept of artificial intelligence(AI)was first presented at the Dartmouth SummerResearch Project on AI hosted by McCarthy and Minsky in *** that,the developmentof AI has experienced ups and downs due to some limited conditions including intelligentcomputing techniques,computer and hardware and software^([1,2]).In particular,with the rapidof deep artificial neural networks,machine learning(ML)and deep learning(DL)techniques^([3,4])have been applied in many fields of science and engineering,including machine translation,image recognition,genomics,scientific computing and atmospheric science,etc^([5]).

关键词： has artificial hardware

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基于子结构的有限元模型修正方法

振动与冲击 2017年第4期36卷 99-104,138页

作者：翁顺左越朱宏平陈波赵会贤田炜颜永逸华中科技大学土木工程与力学学院控制结构湖北省重点实验室武汉430074 武汉理工大学土木工程与建筑学院武汉430070

提出了一种基于子结构的有限元模型修正方法。该方法将整体结构有限元模型划分为多个子结构模型,求解独立子结构的主模态特征解和特征灵敏度;通过位移协调条件和能量方程,约束相邻独立子结构,得到整体结构的特征解和特征灵敏度;并以整... 详细信息

提出了一种基于子结构的有限元模型修正方法。该方法将整体结构有限元模型划分为多个子结构模型,求解独立子结构的主模态特征解和特征灵敏度;通过位移协调条件和能量方程,约束相邻独立子结构,得到整体结构的特征解和特征灵敏度;并以整体结构模态和结构试验模态的残差为目标函数,通过调整子结构单元参数,完成有限元模型修正。当结构局部参数发生变化,通过分析某一个或几个子结构即可求解整体结构特征解和特征灵敏度,而不需要分析其他未发生变化的子结构。由于子结构模型尺寸远小于整体结构,该方法能够极大地提高有限元模型修正方法的精度和效率。

关键词：有限元模型修正损伤识别子结构特征解特征灵敏度

Large eddy simulation study of 3D wind field in a complex mountainous area under different boundary conditions

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第7期25卷 541-556页

作者： yan LI Lei yan Xuhui HE School of Civil Engineering Central South UniversityChangsha410075China National Engineering Research Center for High-speed Railway Construction Changsha410075China Hunan Provincial Key Laboratory for Disaster Prevention and Mitigation of Rail Transit Engineering Structures Changsha410075China

Large eddy simulations generally are used to predict 3D wind field characteristics in complex mountainous *** simulation boundary conditions,such as the height and length of the computational domain or the characteristics of inflow turbulence,can significantly impact the quality of *** this study,we examined these boundary conditions within the context of the mountainous terrain around a long-span cable-stayed bridge using a wind tunnel *** sizes of computational domains and turbulent incoming wind velocities were used in large eddy *** results show that when the height of the computational domain is five times greater than the height of the terrain model,there is minimal influence from the top wall on the wind field characteristics in this complex mountainous *** the length of the wake region of the computational domain has negligible effects on the wind *** in the inlet boundary reduces the length of the wake region on a leeward hill with a low slope,but has less impact on the mean wind velocity of steep hills.

关键词： Large eddy simulation(LES) Spectral representation method Recycling method High mountainous canyon Wind characteristics Atmospheric boundary layer Computational domain

Electromagnetic characteristic analysis and design of a linear motor used for ultra-high-speed EMS maglev train

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Science China(Technological Sciences) 2024年第6期67卷 1957-1973页

作者： GAO Han SHI TingNa GAO XinMai LEI yanXiao yan Dong GUO Liyan yan yan College of Electrical Engineering Zhejiang UniversityHangzhou310027China Zhejiang University Advanced Electrical Equipment Innovation Center Hangzhou311107China State Key Laboratory of High-speed Maglev Transportation Technology Qingdao266100China CRRC Qingdao Sifang Co.Ltd. Qingdao266111China

The operating speed of the commercial electromagnetic suspension(EMS)maglev train has been over 430 km/h,making it the fastest means of land *** the increasing demands of people traveling,it is necessary to further improve the operating speed of maglev *** to examine whether the existing EMS system can meet the requirements of ultra-highspeed operation(more than 600 km/h),the electromagnetic characteristics of an EMS linear motor under the operating speed of 600–1000 km/h fed by a square-wave voltage supply is investigated in this ***,an electromagnetic field model of the EMS system under the square-wave voltage supply is established to investigate its electromagnetic performance,e.g.,the characteristics of phase current,the magnetic flux density,and the electromagnetic ***,the relationship between the harmonic components of the air-gap magnetic flux density and electromagnetic force is investigated using the two-dimensional fast Fourier transform(2D-FFT)to reveal the mechanism of electromagnetic force ***,to address the issues of excessive armature current density and significant electromagnetic force ripple,the linear motor is re-designed by enlarging the stator slot area and reshaping the mover's main magnetic ***,the Taguchi method is used to further improve the electromagnetic characteristics of the linear electric ***,the effectiveness of the proposed optimal design is validated by the finite-element analysis(FEA)based co-simulation.

关键词： ultra-high-speed maglev transportation electromagnetic suspension(EMS) linear motor electromagnetic force ripple suppression