资源类型

期刊论文 32

年份

2023 2

2022 2

2021 2

2020 1

2019 2

2018 1

2017 1

2015 1

2014 3

2013 1

2012 1

2011 1

2009 5

2006 3

2005 3

2003 1

2002 1

2000 1

展开 ︾

关键词

应力波 2

消失波 2

GH位移 1

Maxwell方程组 1

Proca方程组 1

一维应力波 1

主动源面波 1

传播与演化 1

光子 1

光子的静止质量 1

光子静质量 1

光波 1

几率 1

可编程超表面 1

围岩增耦 1

地下工程结构 1

地震监测 1

声表面波 1

复杂地形 1

展开 ︾

检索范围：

排序： 展示方式：

Soil seismic analysis for 2D oblique incident waves using exact free-field responses by frequency-based

《结构与土木工程前沿（英文）》 2022年 第16卷 第12期   页码 1530-1551 doi: 10.1007/s11709-022-0900-7

摘要： The seismic analysis of a viscoelastic half-space under two-dimensional (2D) oblique incident waves is carried out by the finite/infinite element method (FIEM). First, the frequency-domain exact solutions for the displacements and stresses of the free field are derived in general form for arbitrary incident P and SV waves. With the present formulation, no distinction needs to be made for SV waves with over-critical incident angles that make the reflected P waves disappear, while no critical angle exists for P waves. Next, the equivalent seismic forces of the earthquake (Taft Earthquake 1952) imposed on the near-field boundary are generated by combining the solutions for unit ground accelerations with the earthquake spectrum. Based on the asymmetric finite/infinite element model, the frequency-domain motion equations for seismic analysis are presented with the key parameters selected. The results obtained in frequency and time domain are verified against those of Wolf’s, Luco and de Barros’ and for inversely computed ground motions. The parametric study indicated that distinct phase difference exists between the horizontal and vertical responses for SV waves with over-critical incident angles, but not for under-critical incident angles. Other observations were also made for the numerical results inside the text.

关键词： oblique incident waves     critical angle     half-space     finite/infinite element approach     seismic response analysis    

HTML PDF 收藏

波浪入射角及地形对浮体水动力学特性影响的有限元分析

刘荣,郑永红,游亚戈,孙晓燕,

《中国工程科学》 2005年 第7卷 第3期   页码 42-48

摘要：

利用有限元方法分析了二维情况下波浪入射角及地形对浮体水动力学特性的影响，计算了不同情况下浮体的水动力学系数；通过与简单地形情况下解析解的比较，验证了数值方法的正确性；并在分析中采用了BiCGStab算法，高效地求解离散形成的线性方程组，大大地提高了分析的效率。研究结果为海上结构物的设计提供了关键的水动力学数据。

关键词： 波浪     浮体     斜向波     复杂地形     有限元    

HTML PDF 收藏

Modeling oblique load carrying capacity of batter pile groups using neural network, random forest regression

Tanvi SINGH, Mahesh PAL, V. K. ARORA

《结构与土木工程前沿（英文）》 2019年 第13卷 第3期   页码 674-685 doi: 10.1007/s11709-018-0505-3

摘要： M5 model tree, random forest regression (RF) and neural network (NN) based modelling approaches were used to predict oblique load carrying capacity of batter pile groups using 247 laboratory experiments with smooth and rough pile groups. Pile length ( ), angle of oblique load ( ), sand density ( ), number of batter piles ( ), and number of vertical piles ( ) as input and oblique load ( ) as output was used. Results suggest improved performance by RF regression for both pile groups. M5 model tree provides simple linear relation which can be used for the prediction of oblique load for field data also. Model developed using RF regression approach with smooth pile group data was found to be in good agreement for rough piles data. NN based approach was found performing equally well with both smooth and rough piles. Sensitivity analysis using all three modelling approaches suggest angle of oblique load ( ) and number of batter pile ( ) affect the oblique load capacity for both smooth and rough pile groups.

关键词： batter piles     oblique load test     neural network     M5 model tree     random forest regression     ANOVA    

HTML PDF 收藏

On subsurface box-shaped lined tunnel under incident SH-wave propagation

《结构与土木工程前沿（英文）》 2021年 第15卷 第4期   页码 948-960 doi: 10.1007/s11709-021-0740-x

摘要： In this paper, a half-plane time-domain boundary element method is applied to obtain the seismic ground response, including a subsurface box-shaped lined tunnel deployed in a linear homogenous elastic medium exposed to obliquely incident SH-waves. Only the boundary around the tunnel is required to be discretized. To prepare an appropriate model by quadratic elements, a double-node procedure is used to receive dual boundary fields at corners as well as change the direction of the normal vector. After encoding the method in a previously confirmed computer program, a numerical study is carried out to sensitize some effective parameters, including frequency content and incident wave angle for obtaining a surface response. The depth and impedance ratio of the lining are assumed to be unvaried. The responses are illustrated in the time and frequency domains as two/three-dimensional graphs. The results showed that subsurface openings with sharp corners distorted the propagation path of the anti-plane waves to achieve the critical states on the ground surface. The present approach can be proposed to civil engineers for preparing simple underground box-shaped models with angular boundaries.

关键词： box-lined tunnel     half-plane BEM     surface response     SH-wave     time-domain    

HTML PDF 收藏

不同类型阴道斜隔综合征妊娠3例报告

陈秀娟,熊秀梅,林元

《中国工程科学》 2014年 第16卷 第5期   页码 90-95

摘要：

阴道斜隔综合征发病率低，Burgis 等曾报道发病率为0.1 %～3.8 %，其临床上有3 种分型，不同类型的斜隔综合征临床表现各不同，阴道斜隔综合征合并妊娠常因复杂的生殖道畸形造成人工流产困难。本文通过报告3 种类型的斜隔综合征患者终止非意愿性妊娠各一例，说明阴道斜隔综合征合并妊娠在诊断和处理上有一定的难度，存在误诊和漏诊，因此需要临床医师、超声医师共同提高对该病的认识，提高诊断准确性，从而指导临床治疗。

关键词： 阴道斜隔综合征     妊娠     超声     治疗    

HTML PDF 收藏

A numerical framework for underground structures in layered ground under inclined P-SV waves using stiffness

《结构与土木工程前沿（英文）》 2023年 第17卷 第1期   页码 10-24 doi: 10.1007/s11709-022-0904-3

摘要： A numerical framework was proposed for the seismic analysis of underground structures in layered ground under inclined P-SV waves. The free-field responses are first obtained using the stiffness matrix method based on plane-wave assumptions. Then, the domain reduction method was employed to reproduce the wavefield in the numerical model of the soil–structure system. The proposed numerical framework was verified by providing comparisons with analytical solutions for cases involving free-field responses of homogeneous ground, layered ground, and pressure-dependent heterogeneous ground, as well as for an example of a soil–structure interaction simulation. Compared with the viscous and viscous-spring boundary methods adopted in previous studies, the proposed framework exhibits the advantage of incorporating oblique incident waves in a nonlinear heterogeneous ground. Numerical results show that SV-waves are more destructive to underground structures than P-waves, and the responses of underground structures are significantly affected by the incident angles.

关键词： underground structures     seismic response     stiffness matrix method     domain reduction method     P-SV waves    

HTML PDF 收藏

Emergency drinking water treatment in source water pollution incident-technology and practice in China

Xiaojian ZHANG , Chao CHEN ,

《环境科学与工程前沿（英文）》 2009年 第3卷 第3期   页码 364-368 doi: 10.1007/s11783-009-0027-2

摘要： An investigation into emergency potable water treatment technologies was conducted to investigate China’s water pollution situation. In order to confirm optimum parameters, the technological efficiency of each pollutant was obtained. About 100 contaminants were tested to find the emergency treatment technologies, most of which were found to be positive. This paper presents the three largest and most significant water pollution incidents in China to date, analyzing cases such as the nitrobenzene pollution incident in the Songhua River in November 2005, the cadmium pollution incident in the Beijiang River in December 2005, and the water crisis with odorous tap water in Wuxi City in May 2007.

关键词： emergency drinking water treatment     water pollution     adsorption     oxidation     precipitation    

HTML PDF 收藏

Serum uric acid and risk of incident diabetes in middle-aged and elderly Chinese adults: prospective

Di Cheng, Chunyan Hu, Rui Du, Hongyan Qi, Lin Lin, Xueyan Wu, Lina Ma, Kui Peng, Mian Li, Min Xu, Yu Xu, Yufang Bi, Weiqing Wang, Yuhong Chen, Jieli Lu

《医学前沿（英文）》 2020年 第14卷 第6期   页码 802-810 doi: 10.1007/s11684-019-0723-7

摘要： The association between serum uric acid and the risk of incident diabetes in Chinese adults remains unknown. This study aimed to investigate this association in a community-dwelling population aged≥40 years in Shanghai, China. Oral glucose tolerance test was conducted during baseline and follow-up visits. Relative risk regression was utilized to examine the associations between baseline gender-specific serum uric acid levels and incident diabetes risk. A total of 613 (10.3%) incident diabetes cases were identified during the follow-up visit after 4.5 years. Fasting plasma glucose, postload glucose, and glycated hemoglobin A1c during the follow-up visit progressively increased across the sex-specific quartiles of serum uric acid (all s<0.05). The incidence rate of diabetes increased across the quartiles of serum uric acid (7.43%, 8.77%, 11.47%, and 13.43%). Multivariate adjusted regression analysis revealed that individuals in the highest quartile had 1.36-fold increased risk of diabetes compared with those in the lowest quartile of serum uric acid (odds ratio (95% confidence interval) = 1.36 (1.06−1.73)). Stratified analysis indicated that the association was only observed in women. Accordingly, serum uric acid was associated with the increased risk of incident diabetes among middle-aged and elderly Chinese women.

关键词： incident diabetes     prospective study     uric acid    

HTML PDF 收藏

Ribbon bridge in waves based on hydroelasticity theory

Cong WANG, Shixiao FU, Weicheng CUI

《结构与土木工程前沿（英文）》 2009年 第3卷 第1期   页码 57-62 doi: 10.1007/s11709-009-0005-6

摘要： For the design and operation of a floating bridge, the understanding of its hydroelastic behavior in waves is of great importance. This paper investigated the hydroelastic performances of a ribbon bridge under wave action. A brief introduction on the estimation of dynamic responses of the floating bridge and the comparisons between the experiments and estimation were presented. Based on the 3D hydroelasticity theory, the hydroelastic behavior of the ribbon bridge modeled by finite element method (FEM) was analyzed by employing the mode superposition method. And the relevant comparisons between the numerical results and experimental data obtained from one tenth scale elastic model test in the ocean basin were made. It is found that the present method is applicable and adaptable for predicting the hydroelastic response of the floating bridge in waves.

关键词： hydroelasticity     ribbon bridge     wave     finite element method (FEM)    

HTML PDF 收藏

非均质岩体中一维应力波演化过程分析

钟光复,王志亮,李永池

《中国工程科学》 2006年 第8卷 第5期   页码 58-62

摘要：

地下球形药包爆轰后将产生很强的地震波，其传播受到多种因素的影响。把岩石介质的弹塑性帽盖模型耦合到有限差分法程序中，对一维爆轰波在非均质岩石体中的传播、演化机理进行了数值模拟与分析；着重探讨了一维应力波从“硬”岩石层进入“软”岩石层、从“软”岩石层进入“硬”岩石层时，波在形状和强度等方面的变化规律；同时探讨了岩石介质中存在的“软弱夹层”对一维应力波传播的影响。

关键词： 岩石介质     一维应力波     帽盖模型     传播与演化    

HTML PDF 收藏

A novel light fluctuation spectrum method for in-line particle sizing

Shouxuan QIN, Xiaoshu CAI, Li MA

《能源前沿（英文）》 2012年 第6卷 第1期   页码 89-97 doi: 10.1007/s11708-012-0176-z

摘要： This paper discusses two problems in in-line particle sizing when using light fluctuation method. First, by retrieving the ratio of particle concentrations at different time, the intensity of incident light is obtained. There exists narrow error between the calculated and pre-detected value of the intensity of incident light. Secondly, by combining spectrum analysis with Gregory’s theory, a multi-sub-size zone model is proposed, with which the relationship between the distribution of turbidity and the particle size distribution (PSD) can be established, and an algorithm developed to determine the distribution of turbidity. Experiments conducted in the laboratory indicate that the measured size distribution of pulverized coal conforms well with the imaging result.

关键词： in-line measurement     particle size distribution (PSD)     incident light intensity     particle concentration     light fluctuation    

HTML PDF 收藏

Propagation characteristics of transient waves in low-strain integrity testing on cast-in-situ concrete

Hanlong LIU, Xuanming DING

《结构与土木工程前沿（英文）》 2009年 第3卷 第2期   页码 240-240 doi: 10.1007/s11709-009-0100-8

HTML PDF 收藏

利用人工源超低频电磁波监测地震的试验与分析

赵国泽,陆建勋

《中国工程科学》 2003年 第5卷 第10期   页码 27-33

摘要：

由人工产生大功率超低频（SLF）电磁波可以在地面很大范围的许多测点同时测量该信号，利用它可以研究地下电阻率结构和空间电磁场；研究地震等引起的电磁场异常变化；探测地壳结构和地下资源，具有广阔的应用前景和发展潜力。在北京等地区的观测表明,SLF信号的功率谱密度超过天然场源信号数倍以上，所得到的视电阻率数据精度远高于天然源方法，并有长时间的稳定性。在试验测量期间距测点约120 km发生的迁安4.2级地震与观测的电磁场异常和视电阻率的变化有较好的对应性,对产生这些变化的可能的成因机制进行了分析和探讨。

关键词： 超低频/极低频电磁波     电磁异常     电阻率     地震监测    

HTML PDF 收藏

Experimental verification of the interface wave method to detect interlaminar damage of a metal multilayer structure

Bing LI,Xu GENG,Tong LU,Lei QIANG,Minghang LI

《机械工程前沿（英文）》 2015年 第10卷 第4期   页码 380-391 doi: 10.1007/s11465-015-0365-7

摘要：

The interface wave traveling along the boundary of two materials has been studied for nearly a century. However, experiments, engineering applications, and interface wave applications to the non-destructive inspection of interlaminar composite have developed slowly. In this research, an experiment that applies Stoneley waves (a type of interfacial wave between two solid half-spaces) is implemented to detect the damage in a multilayer structure. The feasibility of this method is also verified. First, the wave velocity and wave structure of Stoneley waves at a perfectly bonded aluminum-steel interface are obtained by solving the Stoneley wave dispersion equation of two elastic half-spaces. Thereafter, an experiment is conducted to measure the Stoneley wave velocity of an aluminum-steel laminated beam and to locate interlaminar cracks by referring to the Stoneley wave velocity and echo wave time. Results indicate that the location error is less than 2%. Therefore, Stoneley waves show great potential as a non-destructive inspection method of a multilayer structure.

关键词： crack localization     interface waves     Stoneley waves     interlaminar damage     multilayer structure    

HTML PDF 收藏

波粒二象性理论的若干问题

黄志洵

《中国工程科学》 2002年 第4卷 第1期   页码 54-63

摘要：

论述了光波和物质波的波粒二象性理论的发展，讨论了该理论的存留问题。认为光子的静质量和光子的内部结构仍是科学中的关键性疑点。指出，虽然波粒二象性成立的前提是波长足够小，但在现有理论中却提不出一条清晰的界线。讨论了光波和电磁波是物质还是物质属性的问题。提出了对de Broglie波超光速相速的疑问。分析表明，如何建立电磁脉冲的粒子形象的问题仍需解决。此外，探讨了当电磁脉冲以超光速传播时相对论是否受破坏。最后，讨论了消失波的粒子性和虚光子问题。

关键词： 光子     光波     物质波     波粒二象性     孤子     电磁脉冲     超光速     消失波     虚光子    

HTML PDF 收藏

标题 作者 时间 类型 操作

Soil seismic analysis for 2D oblique incident waves using exact free-field responses by frequency-based

期刊论文

波浪入射角及地形对浮体水动力学特性影响的有限元分析

刘荣,郑永红,游亚戈,孙晓燕,

期刊论文

Modeling oblique load carrying capacity of batter pile groups using neural network, random forest regression

Tanvi SINGH, Mahesh PAL, V. K. ARORA

期刊论文

On subsurface box-shaped lined tunnel under incident SH-wave propagation

期刊论文

不同类型阴道斜隔综合征妊娠3例报告

陈秀娟,熊秀梅,林元

期刊论文

A numerical framework for underground structures in layered ground under inclined P-SV waves using stiffness

期刊论文

Emergency drinking water treatment in source water pollution incident-technology and practice in China

Xiaojian ZHANG , Chao CHEN ,

期刊论文

Serum uric acid and risk of incident diabetes in middle-aged and elderly Chinese adults: prospective

Di Cheng, Chunyan Hu, Rui Du, Hongyan Qi, Lin Lin, Xueyan Wu, Lina Ma, Kui Peng, Mian Li, Min Xu, Yu Xu, Yufang Bi, Weiqing Wang, Yuhong Chen, Jieli Lu

期刊论文

Ribbon bridge in waves based on hydroelasticity theory

Cong WANG, Shixiao FU, Weicheng CUI

期刊论文

非均质岩体中一维应力波演化过程分析

钟光复,王志亮,李永池

期刊论文

A novel light fluctuation spectrum method for in-line particle sizing

Shouxuan QIN, Xiaoshu CAI, Li MA

期刊论文

Propagation characteristics of transient waves in low-strain integrity testing on cast-in-situ concrete

Hanlong LIU, Xuanming DING

期刊论文

利用人工源超低频电磁波监测地震的试验与分析

赵国泽,陆建勋

期刊论文

Experimental verification of the interface wave method to detect interlaminar damage of a metal multilayer structure

Bing LI,Xu GENG,Tong LU,Lei QIANG,Minghang LI

期刊论文

波粒二象性理论的若干问题

黄志洵

期刊论文