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新型工业化的历史演进、时代特色与推进路径

北京师范大学学报（社会科学版） 2024年第3期 19-27页

作者：李婧王跃生华北电力大学马克思主义学院北京100096 北京大学经济学院北京100871

工业化是现代化的基础和前提,推进新型工业化是实现中国式现代化的必然要求。从历史维度看,新型工业化最初萌芽于社会主义工业化构想中,曲折演进于中国工业化的道路探索中,成熟于中国特色新型工业化道路建设中。从理论维度看,新型工业... 详细信息

工业化是现代化的基础和前提,推进新型工业化是实现中国式现代化的必然要求。从历史维度看,新型工业化最初萌芽于社会主义工业化构想中,曲折演进于中国工业化的道路探索中,成熟于中国特色新型工业化道路建设中。从理论维度看,新型工业化相较于西方工业化实现了五方面突破创新:价值基础是以人为本而非资本驾驭人本;动力机制是技术与制度协同创新而非技术创新单线引领;目标理念为区域和产业协同推进而非利润引导的失衡发展;发展模式为并联式协调发展而非串联式单维发展;对外关系为开放合作、互利共赢而非内向自利、零和博弈。从现实维度看,加快推进新型工业化,应在需求侧扩大人民有效需求,在供给侧培育壮大自主创新增长引擎,以“四化同步”畅通国内循环,以高水平开放推动国内国际双循环相互促进。

关键词：新型工业化中国式现代化中国特色实体经济

脓毒症伴急性肾损伤患者48h内有创通气风险的预测模型的建立与验证

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中华急诊医学杂志 2024年第4期33卷 549-557页

作者：王跃胜周晓莎陈剑平王斌温州医科大学附属东阳医院急诊科东阳322100

目的识别出48 h内有创通气风险大的脓毒症伴急性肾损伤患者,尽早进行干预,改善预后。方法收集2011年1月-2023年10月东阳市人民医院收治的脓毒症伴急性肾损伤患者的资料,分成建模及验证人群,在建模人群中分析与患者入院后48 h内需有创通... 详细信息

目的识别出48 h内有创通气风险大的脓毒症伴急性肾损伤患者,尽早进行干预,改善预后。方法收集2011年1月-2023年10月东阳市人民医院收治的脓毒症伴急性肾损伤患者的资料,分成建模及验证人群,在建模人群中分析与患者入院后48 h内需有创通气的独立危险因素,以此建立列线图预测模型。在建模人群和验证人群中用ROC曲线下面积(AUC)评估模型的判别能力,用GiViTI校准图评估模型的校准度,用决策曲线(DCA)评估预测模型的临床有效性。此外,用SOFA评分及NEWS评分建立的模型、多种机器学习(SVM、C5.0、XGBoos和集成方法)模型与诺模图模型进行比较(Delong检验)。结果共有773例患者纳入研究,住院期间出现呼吸衰竭的独立危险因素为乳酸、B型脑钠肽前体(pro-BNP)、D二聚体、经皮血氧饱和度和肺部感染。建模人群和验证人群中的AUC值分别为0.845和0.880,有良好的校准度和临床有效性。SOFA评分建立的模型在建模人群中AUC值为0.703,验证人群中为0.763,低于诺模图模型(P0.05)。结论基于乳酸、pro-BNP、D二聚体、经皮血氧饱和度和肺部感染的列线图模型可有效预测脓毒症伴急性肾损伤患者入院后48 h内有创通气的风险。

关键词：脓毒症急性肾损伤有创通气预测模型机器学习

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基于组合超表面的跨水空声波调控研究

力学学报 2024年第2期56卷 409-421页

作者：张少聪朱家辉李辰洋瓮佳轩王艳锋汪越胜天津大学力学系天津300350 北京交通大学力学系北京100044

现有声学超表面的研究多是针对空气或水等单一介质,有关跨介质声波调控的研究相对较少.文章主要基于组合超表面研究跨水空界面声波的调控特性.首先,利用遗传算法设计了可以调控波前的高透射空气声超表面.接着,通过复合离散型跨水空高透... 详细信息

现有声学超表面的研究多是针对空气或水等单一介质,有关跨介质声波调控的研究相对较少.文章主要基于组合超表面研究跨水空界面声波的调控特性.首先,利用遗传算法设计了可以调控波前的高透射空气声超表面.接着,通过复合离散型跨水空高透射超表面设计组合超表面实现了对跨水空界面声波的波前调控,并讨论了组合超表面间距对波控性能的影响.最后加工制作组合超表面试样,并对跨水空声波聚焦功能进行了实验验证.结果表明通过复合两种独立设计的超表面可以实现跨水空界面声波的异常折射和聚焦功能.组合超表面的间距会影响其对声波的调控效果.当间距较小时,组合超表面虽然可以实现对跨水空界面声波的调控,但是调控效果较差;随着间距的增加,组合超表面对跨水空声波的调控效果会迅速增强并趋于稳定.在实验中观察到了跨水空界面的声聚焦现象以及组合超表面间距对跨水空界面声波聚焦效果的影响,实验结果与仿真结果基本一致.研究工作为跨水空声学器件的设计提供了一定的数值和实验基础.

关键词：组合声学超表面水空气界面间距异常折射声聚焦

Dynamic Response of a Coated Half-Plane with Hysteretic Damping Under a Harmonic Hertz Load

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Acta Mechanica Solida Sinica 2020年第4期33卷 449-463页

作者： Xiaomin wang Liaoliang Ke yuesheng wang Institute of Engineering Mechanics Beijing Jiaotong UniversityBeijing 100044China School of Mechanical Engineering Tianjin UniversityTianjin 300350China

This paper investigates the dynamic response of a coated half-plane subjected to a harmonic Hertz load on the coating *** complex modulus is used to describe the hysteretic damping of the elastic homogeneous coating and *** the Helmholtz decomposition and Fourier integral transform technique,we derive the stresses and displacements of the coating and half-plane from Navier5s elasticdynamic equations in the form of complex ***,the global adaptive quadrature algorithm is exploited to solve the complex integrals *** effects of Young’s modulus ratio,density ratio,coating thickness,loss factor and external excitation frequency are *** is found that the dynamic response of displacements and stresses becomes increasingly oscillatory with the increase in excitation frequency.

关键词： Dynamic response Coating Hysteretic damping Harmonic Hertz load

Tunable three-dimensional nonreciprocal transmission in a layered nonlinear elastic wave metamaterial by initial stresses

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Applied Mathematics and Mechanics(English Edition) 2022年第2期43卷 167-184页

作者： Zhenni LI Yize wang yuesheng wang Institute of Engineering Mechanics Beijing Jiaotong UniversityBeijing100044China Department of Mechanics Tianjin UniversityTianjin300350China

In this work,the three-dimensional(3 D)propagation behaviors in the nonlinear phononic crystal and elastic wave metamaterial with initial stresses are *** analytical solutions of the fundamental wave and second harmonic with the quasilongitudinal(qP)and quasi-shear(qS_(1) and qS_(2))modes are *** on the transfer and stiffness matrices,band gaps with initial stresses are obtained by the Bloch *** transmission coefficients are calculated to support the band gap property,and the tunability of the nonreciprocal transmission by the initial stress is *** work is expected to provide a way to tune the nonreciprocal transmission with vector characteristics.

关键词： nonlinear elastic wave metamaterial nonreciprocal transmission three-dimensional(3D)elastic wave initial stress

Band structure calculations of in-plane waves in two-dimensional phononic crystals based on generalized multipole technique

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Applied Mathematics and Mechanics(English Edition) 2015年第5期36卷 557-580页

作者： Zhijie SHI yuesheng wang Chuanzeng ZHANG Institute of Engineering Mechanics Beijing Jiaotong University Department of Civil Engineering University of Siegen

A numerical method, the so-called multiple monopole（MMoP） method,based on the generalized multipole technique（GMT） is proposed to calculate the band structures of in-plane waves in two-dimensional phononic crystals, which are composed of arbitrarily shaped cylinders embedded in a solid host medium. To find the eigenvalues（eigenfrequencies） of the problem, besides the sources used to expand the wave fields, an extra monopole source is introduced which acts as the external excitation. By varying the excitation frequency, the eigenvalues can be localized as the extreme points of an appropriately chosen function. By sweeping the frequency range of interest and the boundary of the irreducible first Brillouin zone（FBZ）, the band structures can be obtained. Some typical numerical examples with different acoustic impedance ratios and with inclusions of various shapes are presented to validate the proposed method.

关键词： triangular validate impedance excitation collocation searching elliptical cylinders irreducible scattered

Wavelet-based method for computing elastic band gaps of one-dimensional phononic crystals

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Science China(Physics,Mechanics & Astronomy) 2007年第5期50卷 622-630页

作者： YAN ZhiZhong wang yuesheng Institute of Engineering Mechanics Beijing Jiaotong University Beijing 100044 China Institute of Engineering Mechanics Beijing Jiaotong University Beijing 100044 China

A wavelet-based method was developed to compute elastic band gaps of one-dimensional phononic crystals. The wave field was expanded in the wavelet basis and an equivalent eigenvalue problem was derived in a matrix form involving the adaptive computation of integrals of the wavelets. The method was then applied to a binary system. For comparison, the elastic band gaps of the same one-dimensional phononic crystals computed with the wavelet method and the well- known plane wave expansion (PWE) method are both presented in this paper. The numerical results of the two methods are in good agreement while the computation costs of the wavelet method are much lower than that of PWE method. In addition, the adaptability of wavelets makes the method possible for efficient band gap computation of more complex phononic structures.

关键词： phononic crystals, elastic band gap, wavelet method, plane wave expansion (PWE) method

国际运输通道对地区创业活跃度的影响研究——基于中欧班列开通的准自然实验

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新视野 2024年第2期 22-33页

作者：王跃生朱子阳李亚楠北京大学经济学院北京市100871 北京大学-中国银行欧盟经济与战略研究中心北京市100871 安徽省社会科学院经济研究所合肥市230601

中欧班列是“一带一路”互联互通的重要基础设施之一,也是中欧经贸合作的关键领域。通过构建2000—2021年中国地级市层面面板数据集,基于中欧班列开通这一政策冲击,使用渐进双重差分的方法,实证研究了以中欧班列为代表的国际运输通道对... 详细信息

中欧班列是“一带一路”互联互通的重要基础设施之一,也是中欧经贸合作的关键领域。通过构建2000—2021年中国地级市层面面板数据集,基于中欧班列开通这一政策冲击,使用渐进双重差分的方法,实证研究了以中欧班列为代表的国际运输通道对于地区创业活跃度的影响。研究发现,中欧班列开通显著促进了新企业的形成与地区创业活跃度的提高,且这一结论经过一系列稳健性检验仍然成立。进一步的机制分析表明,中欧班列主要通过提升外部市场可达性与促进区域创新高质量发展,进而提升了地区创业活跃度。此外,中欧班列对创业的积极影响存在显著异质性,在东部地区、市场化程度更高地区以及距港口较远地区,其作用更强。

关键词：国际运输通道中欧班列新企业形成创业活跃度

Boundary element method for calculation of elastic wave transmission in two-dimensional phononic crystals

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Science China(Physics,Mechanics & Astronomy) 2016年第6期59卷 58-67页

作者： FengLian Li yuesheng wang ChuanZeng Zhang School of Mechanical and Engineering Beijing Information Science and Technology University Institute of Engineering Mechanics Beijing Jiaotong University Department of Civil Engineering University of Siegen

A boundary element method(BEM) is presented to compute the transmission spectra of two-dimensional(2-D) phononic crystals of a square lattice which are finite along the x-direction and infinite along the *** cross sections of the scatterers may be circular or *** a periodic cell,the boundary integral equations of the matrix and the scatterers are *** the periodic boundary conditions and the interface continuity conditions,a linear equation set is formed,from which the elastic wave transmission can be *** the transmission spectra,the band gaps can be identified,which are compared with the band structures of the corresponding infinite *** is shown that generally the transmission spectra completely correspond to the band *** addition,the accuracy and the efficiency of the boundary element method are analyzed and discussed.

关键词： phononic crystals boundary element method elastic wave transmission spectra