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文章速递Interaction phenomena between lump and solitary wave of a generalized (3+1)-dimensional variable-coefficient nonlinear-wave equation in liquid with gas bubbles 认领
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作者 Jian-Guo Liu Wen-Hui Zhu +1 位作者 Yan He Ya-Kui Wu 《理论物理通讯:英文版》 SCIE CAS CSCD 2020年第8期18-26,共9页
In this paper, a generalized (3+1)-dimensional variable-coefficient nonlinear-wave equation is studied in liquid with gas bubbles. Based on the Hirota’s bilinear form and symbolic computation, lump and interaction so... In this paper, a generalized (3+1)-dimensional variable-coefficient nonlinear-wave equation is studied in liquid with gas bubbles. Based on the Hirota’s bilinear form and symbolic computation, lump and interaction solutions between lump and solitary wave are obtained,which include a periodic-shape lump solution, a parabolic-shape lump solution, a cubic-shape lump solution, interaction solutions between lump and one solitary wave, and between lump and two solitary waves. The spatial structures called the bright lump wave and the bright-dark lump wave are discussed. Interaction behaviors of two bright-dark lump waves and a periodic-shape bright lump wave are also presented. Their interactions are shown in some 3D plots. 展开更多
关键词 solitary wave lump wave variable-coefficient nonlinear-wave equation interaction behaviors
Simple Push-Type Wave Generating Method Using Digital Rotary Valve Control 认领
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作者 Yi Liu Jiafei Zheng +3 位作者 Ruiyin Song Qiaoning Xu Junhua Chen Fangping Huang 《中国机械工程学报:英文版》 SCIE EI CAS CSCD 2020年第1期221-231,共11页
The important parameters to describe waves are their amplitude and length.In order to make it easier to improve wave amplitude and facilitate wave experiment,a simple push-type wave generating method using digital rot... The important parameters to describe waves are their amplitude and length.In order to make it easier to improve wave amplitude and facilitate wave experiment,a simple push-type wave generating method using digital rotary valve control was proposed and different wave amplitudes were generated by the new method.After the mathematical model of the new method had been established,numerical analysis based on the linear wave theory was carried out by means of Matlab/Simulink software tools,and experiments were conducted on the push-type wave maker to ascertain the validity of the established model and the numerical simulation results.It shows that both experimental and theoretical results agree relatively well,and the plate motion frequency and amplitude of the push-type wave maker can be continuously adjusted and the various required regular waves can be obtained.Although the wave amplitude and length descends with the increasing of working frequency,the wave amplitude can be improved conveniently by setting the axial opening width of the valve and the oil supply pressure of system.The wave length remains unchanged with the axial opening width and the oil supply pressure change.The research indicates that different regular waves can be easily generated by the new method and the wave amplitude can be further improved in a certain plate motion frequency range. 展开更多
关键词 Push-type WAVE maker DIGITAL rotary valve CONTROL Mathematical modeling WAVE amplitude WAVE frequency
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Submillimeter wave communication versus millimeter wave communication 认领
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作者 Madhuprana Goswami Hyuck M.Kwon 《数字通信与网络:英文版》 2020年第1期64-74,共11页
This paper studies the performance of a submillimeter wave antenna operating between frequencies 0.1 THz and 10 THz with a 4-cyano-4-pentylbiphenyl[5CB]substrate.Since the size and shape of the antenna impact its gain... This paper studies the performance of a submillimeter wave antenna operating between frequencies 0.1 THz and 10 THz with a 4-cyano-4-pentylbiphenyl[5CB]substrate.Since the size and shape of the antenna impact its gain/directivity,resonant frequency,bandwidth,and efficiency,the two antenna types considered in this paper are:(a)Rectangular Patch Antenna(RPA),and(b)Cylindrical Dielectric Resonator Antenna(CDRA).Here a submillimeter wave antenna is compared with a millimeter wave(a few GHz to 100 GHz)antenna.These popular mmwave antennas are chosen for the submillimeter wave antenna in order to understand changes in their performance as the result of changes in their geometrical shape.FEldberechnung bei Korpern mit beliebiger Oberflache(FEKO)software is used for the design and calculation of the Three-Dimensional(3D)ElectroMagnetic(EM)patterns.This paper also concentrates on the design and analysis of a massive submillimeter wave Multiple-Input Multiple-Output(MIMO)(8 by 8)RPA and CDRA. 展开更多
关键词 SUBMILLIMETER WAVE ANTENNA MILLIMETER WAVE ANTENNA Rectangular MICRO-STRIP patch ANTENNA Cylindrical dielectric RESONATOR ANTENNA Massive SUBMILLIMETER WAVE MIMO ANTENNA Applications
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Nonlinear dynamical magnetosonic wave interactions and collisions in magnetized plasma 认领
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作者 M.ISHAQ Hang XU 《应用数学和力学:英文版》 SCIE EI CSCD 2020年第8期1139-1156,共18页
The one-dimensional nonlinear dynamical wave interactions in a system of quasineutral two-fluid plasma in a constant magnetic field are investigated.The existence of the travelling wave solutions is discussed.The modu... The one-dimensional nonlinear dynamical wave interactions in a system of quasineutral two-fluid plasma in a constant magnetic field are investigated.The existence of the travelling wave solutions is discussed.The modulation stability of linear waves and the modulation instability of weakly nonlinear waves are presented.Both suggest that the Korteweg-de Vries(KdV)system is modulationally stable.Besides,the wave interactions including the periodic wave interaction and the solitary wave interaction are captured and presented.It is shown that these interacting waves alternately exchange their energy during propagation.The Fourier spectrum analysis is used to depict the energy transformation between the primary and harmonic waves.It is known that the wave interactions in magnetized plasma play an important role in various processes of heating and energy transportation in space and astrophysical plasma.However,few researchers have considered such magnetohydrodynamic(MHD)wave interactions in plasma.It is expected that this work can provide additional insight into understanding of behaviors of MHD wave interactions. 展开更多
关键词 magnetosonic wave periodic wave solitary wave modulation instability Fourier spectrum dispersion relation
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Experimental study of wave propagation characteristics on a simplified coral reef 认领
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作者 Jia-yi Xu Shu-xue Liu +1 位作者 Jin-xuan Li Wei Jia 《水动力学研究与进展:英文版》 SCIE EI CSCD 2020年第2期385-397,共13页
The wave transformation over slope topography is widely studied,but most of studies are for common coastal slopes.This paper presents an experimental study of 2-D regular and irregular wave transformations on a simpli... The wave transformation over slope topography is widely studied,but most of studies are for common coastal slopes.This paper presents an experimental study of 2-D regular and irregular wave transformations on a simplified coral reef with a steep slope of 1:5 and a horizontal reef flat,focusing on the characteristics of the waves that break on the reef flat.The analyzed results show that the estimates of the wave breaking made by using the well-known previous formulae do not agree completely with the experimental results.When the waves break on a reef flat,the relative breaking wave height(H/d)b is related to the incident deep-water wave steepness and the relative water depth db/L0.Hence,a new criterion for breaking waves on a reef flat is proposed.Furthermore,in view of the fact that the local Ursell number is commonly used to parameterize the wave nonlinearity,the relationships among the skewness,the asymmetry,and the local Ursell number are also presented.Experimental data confirm that when the Ursell number is greater than 30,the absolute values of the skewness and the asymmetry on a reef flat are greater than those on a steep slope. 展开更多
关键词 Coral reef bathymetry wave breaking wave height attenuation representative wave parameter nonlinear parameters
An analytical study on the Rayleigh wave generation in a stratified structure 认领
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作者 A.MANDI S.KUNDU +1 位作者 P.PATI P.C.PAL 《应用数学和力学:英文版》 SCIE EI CSCD 2020年第7期1039-1054,共16页
In this paper,an analytical method is used to investigate the Rayleigh wave generation in a stratified structure and the wave generation in a dry sandy layer constrained between the couple stress and inhomogeneous ort... In this paper,an analytical method is used to investigate the Rayleigh wave generation in a stratified structure and the wave generation in a dry sandy layer constrained between the couple stress and inhomogeneous orthotropic half-spaces.This study is devoted to analyzing the impact of various effective parameters associated with the media on the phase velocities of the wave.The displacement components for each medium are derived by implementing the separable variable method.The frequency equa-tion is secured by using the displacement components in the boundary conditions,imposed at the interfaces between the layer and half-spaces.Moreover,the secured equation is the relation between the phase velocity and the wave number.Numerical computations are performed,and graphical representations are demonstrated between the phase velocity and the wave number for both phase velocities with different values of the parameters.The comparison between the phase velocities is observed for the same value of each pa-rameter. 展开更多
关键词 Rayleigh wave dry sandy layer couple stress ORTHOTROPIC phase velocity wave number
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The Characteristics of Storm Wave Behavior and Its Effect on Cage Culture Using the ADCIRC+SWAN Model in Houshui Bay, China 认领
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作者 YIN Chao HUANG Haijun +2 位作者 WANG Daoru LIU Yanxia GUO Ziyue 《中国海洋大学学报:英文版》 SCIE CAS CSCD 2020年第2期307-319,共13页
The current storm wave hazard assessment tends to rely on a statistical method using wave models and fewer historical data which do not consider the effects of tidal and storm surge.In this paper,the wave-current coup... The current storm wave hazard assessment tends to rely on a statistical method using wave models and fewer historical data which do not consider the effects of tidal and storm surge.In this paper,the wave-current coupled model ADCIRC+SWAN was used to hindcast storm events in the last 30 years.We simulated storm wave on the basis of a large set of historical storms in the North-West Pacific Basin between 1985 and 2015 in Houshui Bay using the wave-current coupled model ADCIRC+SWAN to obtain the storm wave level maps.The results were used for the statistical analysis of the maximum significant wave heights in Houshui Bay and the behavior of wave associated with storm track.Comparisons made between observations and simulated results during typhoon Rammasun(2014)indicate agreement.In addition,results demonstrate that significant wave height in Houshui Bay is dominated by the storm wind velocity and the storm track.Two groups of synthetic storm tracks were designed to further investigate the worst case of typhoon scenarios.The storm wave analysis method developed for the Houshui Bay is significant in assisting government's decision-making in rational planning of deep sea net-cage culture.The method can be applied to other bays in the Hainan Island as well. 展开更多
关键词 storm WAVE ADCIRC+SWAN maximum SIGNIFICANT WAVE height Houshui BAY deep sea net-cage
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基于UG的风扇叶片零件塑模分型设计 认领
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作者 陈起东 《机械工程师》 2020年第5期44-45,48,共3页
以风扇零件为例,运用UG软件对该塑件进行分模;风扇零件具有一定的特殊性,其分型方法与一般塑件分型方法有所不同,利用UG软件中MoldWizard模块对风扇进行分型面设计,并应用UG的WAVE技术,对模仁进行再设计,以实现模具型腔、型芯结构的设... 以风扇零件为例,运用UG软件对该塑件进行分模;风扇零件具有一定的特殊性,其分型方法与一般塑件分型方法有所不同,利用UG软件中MoldWizard模块对风扇进行分型面设计,并应用UG的WAVE技术,对模仁进行再设计,以实现模具型腔、型芯结构的设计合理性,满足风扇塑件生产的设计要求。该设计方法可为同类型塑件的分模设计提供参考。 展开更多
关键词 风扇叶片 UG MoldWizard WAVE 注塑模
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Dispersion-engineered wideband low-profile metasurface antennas 认领
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作者 Wei EILIU Zhi Ning CHEN Xianming QING 《信息与电子工程前沿:英文版》 SCIE EI CSCD 2020年第1期27-38,共12页
A metasurface(MTS)can be characterized in terms of dispersion properties of guided waves and surface waves.By engineering the rich dispersion relations,setting particular boundary conditions,and selecting proper excit... A metasurface(MTS)can be characterized in terms of dispersion properties of guided waves and surface waves.By engineering the rich dispersion relations,setting particular boundary conditions,and selecting proper excitation schemes,multiple adjacent resonance modes can be excited to realize the wideband operation of low-profile MTS antennas.We introduce the operating principles of typical dispersion-engineered MTS antennas,and review the recent progress in dispersion-engineered MTS antenna technology.The miniaturization,circular polarization,beam-scanning,and other functionalities of MTS antennas are discussed.The recent development of MTS antennas has not only provided promising solutions to the wideband and low-profile antenna design but also proven great potential of MTS in developing innovative antenna technologies. 展开更多
关键词 Metasurface ANTENNA Dispersion engineering Composite right/left-handed(CRLH) GUIDED WAVE Surface WAVE WIDEBAND Low profile
Shear wave velocity structure of the crust and upper mantle in Southeastern Tibet and its geodynamic implications 认领
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作者 Zhiqi ZHANG Huajian YAO Yan YANG 《中国科学:地球科学英文版》 SCIE EI CAS CSCD 2020年第9期1278-1293,共16页
Southeastern Tibet,which has complex topography and strong tectonic activity,is an important area for studying the subsurface deformation of the Tibetan Plateau.Through the two-station method on 10-year teleseismic Ra... Southeastern Tibet,which has complex topography and strong tectonic activity,is an important area for studying the subsurface deformation of the Tibetan Plateau.Through the two-station method on 10-year teleseismic Rayleigh wave data from 132 permanent stations in the southeastern Tibetan Plateau,which incorporates ambient noise data,we obtain the interstation phase velocity dispersion data in the period range of 5–150s.Then,we invert for the shear wave velocity of the crust and upper mantle through the direct 3-D inversion method.We find two low-velocity belts in the mid-lower crust.One belt is mainly in the SongPan-GangZi block and northwestern part of the Chuan-Dian diamond block,whereas the other belt is mainly in the Xiaojiang fault zone and its eastern part,the Yunnan-Guizhou Plateau.The low-velocity belt in the Xiaojiang fault zone is likely caused by plastic deformation or partial melting of felsic rocks due to crustal thickening.Moreover,the significant positive radial anisotropy(VSH>VSV)around the Xiaojiang fault zone further enhances the amplitude of low velocity anomaly in our VSVmodel.This crustal low-velocity zone also extends southward across the Red River fault and farther to northern Vietnam,which may be closely related to heat sources in the upper mantle.The two low-velocity belts are separated by a high-velocity zone near the Anninghe-Zemuhe fault system,which is exactly in the inner and intermediate zones of the Emeishan large igneous province(ELIP).We find an obvious high-velocity body situated in the crust of the inner zone of the ELIP,which may represent maficultramafic material that remained in the crust when the ELIP formed.In the upper mantle,there is a large-scale low-velocity anomaly in the Indochina and South China blocks south of the Red River fault.The low-velocity anomaly gradually extends northward along the Xiaojiang fault zone into the Yangtze Craton as depth increases.Through our velocity model,we think that southeastern Tibet is undergoing three different tectonic modes at t 展开更多
关键词 Southeastern Tibet Surface wave tomography Shear wave velocity structure Xiaojiang fault system Emeishan large igneous province Asthenospheric upwelling
Development of two-dimensional numerical wave tank based on lattice Boltzmann method 认领
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作者 Guang-wei Liu Qing-he Zhang Jin-feng Zhang 《水动力学研究与进展:英文版》 SCIE EI CSCD 2020年第1期116-125,共10页
A 2-D numerical wave tank(NWT)is developed using the lattice Boltzmann method(LBM)and a multi-relaxation-time(MRT)collision model coupled with an algebraic volume of fluid(VOF)scheme for free surface tracking.An exter... A 2-D numerical wave tank(NWT)is developed using the lattice Boltzmann method(LBM)and a multi-relaxation-time(MRT)collision model coupled with an algebraic volume of fluid(VOF)scheme for free surface tracking.An external force based on the momentum source function is used to generate the waves,and a zone of porous media is used to absorb the waves.Numerical simulations of the progressive and standing waves show that the NWT can generate stable wave trains in agreement with the analytical solutions and eliminate the re-reflection waves.The NWT is used to simulate two problems encountered in practice,namely:the wave transformation over a submerged breakwater and the wave runup on a sea dike.The numerical predictions are in good agreement with the measured data. 展开更多
关键词 Numerical wave tank(NWT) wave generation method volume of fluid(VOF) lattice Boltzmann method(LBM)
Hemispheric Distribution of Lower-band Chorus Waves Observed by Van Allen Probes 认领
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作者 CHENG Xiaowei GU Xudong +1 位作者 NI Binbin ZHANG Yang 《空间科学学报》 CAS CSCD 北大核心 2020年第2期186-196,共11页
Whistler mode chorus waves are important electromagnetic emissions due to their dual roles in acceleration and loss processes of Earth's radiation belt electrons.A detailed global survey of lower-band chorus is pe... Whistler mode chorus waves are important electromagnetic emissions due to their dual roles in acceleration and loss processes of Earth's radiation belt electrons.A detailed global survey of lower-band chorus is performed using EMFISIS data from Van Allen Probes in near-equatorial orbits.In addition to the confirmation of the positive correlation of chorus wave intensities to geomagnetic activity and dayside-nightside distribution asymmetry of wave amplitude and occurrence probability,the analysis results find that in statistics lower-band chorus emissions exhibit higher wave occurrence rates and larger normalized peak wave frequencies in the magnetically northern hemisphere but somehow stronger peak wave intensities in the magnetically southern hemisphere.While overall the differences between the two magnetically hemispheric distributions tend to be not significant,it is important to establish the magnetically hemispheric distribution profiles of lowerband chorus with respect to L-shell,magnetic local time,and geomagnetic latitude for improved understanding of chorus-induced dynamics of radiation belt electrons. 展开更多
关键词 Lower-band CHORUS HEMISPHERIC DISTRIBUTION WAVE intensities Occurrence rates Normalized peak WAVE frequency
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基于UG NX Wave和UDF的塔型井架参数化建模 认领
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作者 周小峰 雷振军 +1 位作者 王东 黄许澎 《机械工程师》 2020年第7期66-68,共3页
基于UG NX软件,根据塔型井架的结构特点,分析了装配式建模的缺点,提出基于Wave使用自顶向下设计,搭建线框式的控制结构。分析了基于UG NX管道模块的型材库的缺点,提出了基于UDF建型材库的新思路,解决型材的参数化,实现塔型井架参数化,... 基于UG NX软件,根据塔型井架的结构特点,分析了装配式建模的缺点,提出基于Wave使用自顶向下设计,搭建线框式的控制结构。分析了基于UG NX管道模块的型材库的缺点,提出了基于UDF建型材库的新思路,解决型材的参数化,实现塔型井架参数化,同类结构可实现尺寸驱动设计。 展开更多
关键词 WAVE UDF 塔型井架 参数化设计 控制结构
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Evolution characteristics and quantization of wave period variation for breaking waves 认领
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作者 Shu-xiu Liang Zhao-chen Sun +1 位作者 Yan-ling Chang Ying Shi 《水动力学研究与进展:英文版》 SCIE EI CSCD 2020年第2期361-374,共14页
The wave parameters(the wave height and period)are important environmental factors in the ocean engineering design.General numerical wave models,such as SWAN and WAVEWATCH,are widely employed to simulate the wave cond... The wave parameters(the wave height and period)are important environmental factors in the ocean engineering design.General numerical wave models,such as SWAN and WAVEWATCH,are widely employed to simulate the wave conditions.However,significant differences were observed between the measurement and the simulation for both the wave height and period,which asks for wave model improvements.The differences are mainly due to the uncertainty of parameterizing various physical processes,including the wave breaking.The energy transfer and loss during the wave breaking involves an important physical mechanism,and the energy dissipation and the period changes are not well studied.This paper studies the deep and shallow water wave breaking using the wave focusing and the slope platform random wave experiments.The characteristics of the wave periods under different conditions are studied in detail,including the period variation.The results show that the periods change during the wave propagation and breaking processes.The energy transfer caused by the strongly nonlinear interaction between the wave components,as well as the energy loss caused by the wave breaking,are the primary causes.The corresponding relationships are established by fitting the data.For the deep water breaking waves induced by the wave focusing,the spectrally averaged period(SAP)increases,and a positive correlation between the rate of change and the wave steepness is found.In the shallow water,the nonlinear interactions are stronger than in the deep water,the wave periods are significantly reduced,and a negative correlation between the rate of change and a nonlinear parameter is found.The inherent mechanism of the period variation is analyzed based on the energy spectrum distribution variations.The contributions of the nonlinear interactions and the wave breaking to the SAP evolution are discussed. 展开更多
关键词 Wave period wave breaking nonlinear interaction EXPERIMENT
基于ELM模型的SAR海浪有效波高反演方法研究 认领
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作者 王晓晨 贺东旭 刘冰宣 《中国激光》 EI CAS CSCD 北大核心 2020年第7期394-402,共9页
针对合成孔径雷达(SAR)海浪有效波高反演方法开展研究,提出了基于超限学习机(ELM)模型的SAR海浪有效波高经验反演方法。通过对ENVISAT ASAR波模式数据和ECMWF再分析数据进行数据时空匹配得到SAR图像与海浪有效波高的匹配数据集,分别在... 针对合成孔径雷达(SAR)海浪有效波高反演方法开展研究,提出了基于超限学习机(ELM)模型的SAR海浪有效波高经验反演方法。通过对ENVISAT ASAR波模式数据和ECMWF再分析数据进行数据时空匹配得到SAR图像与海浪有效波高的匹配数据集,分别在大匹配数据集和小匹配数据集两种情况下对SAR海洋有效波高反演算法进行经验建模,并与业务化CWAVE算法进行了对比验证。结果表明:大匹配数据集下,所提经验模型的精度为0.87,反演精度总体略逊于CWAVE算法(0.91),但在模型训练效率方面,所提经验算法(0.022 s)要优于CWAVE算法(0.514 s);在小匹配数据集下,所提经验算法反演精度为0.59,模型效率为0.008 s,均远优于CWAVE算法(-0.38和0.318 s)。基于ELM模型可以实现小匹配数据集下SAR海浪有效波高的较高精度反演。 展开更多
关键词 遥感 超限学习机 海浪 有效波#高 ENVISAT ASAR
A simple method of depressing numerical dissipation effects during wave simulation within the Euler model 认领
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作者 Zhe Hu Xiaoying Zhang +3 位作者 Weicheng Cui Fang Wang Xiaowen Li Yan Li 《海洋学报:英文版》 SCIE CAS CSCD 2020年第1期141-156,共16页
Numerical wave tanks are widely-acknowledged tools in studying waves and wave-structure interactions. They can generate waves under realistic scales and offers more information on the fluid field. However, most numeri... Numerical wave tanks are widely-acknowledged tools in studying waves and wave-structure interactions. They can generate waves under realistic scales and offers more information on the fluid field. However, most numerical wave tanks suffer from issues known as the numerical dissipation and numerical dispersion. The former causes wave energy to be slowly dissipated and the latter shifts wave frequencies during wave propagation. This paper proposes a simple method of depressing numerical dissipation effects on the basis of solving Euler equations using the finite difference method(FDM). The wave propagation solutions are solved analytically taking into account the influence of the damping terms. The main idea of the method is to append a source term to the momentum equation, whose strength is determined by how strong the numerical damping effect is. The method is verified by successfully depressing numerical effects during the simulation of regular linear waves, Stokes waves and irregular waves. By applying the method, wave energy is able to be close to its initial value after long distance of travel. 展开更多
关键词 NUMERICAL DISSIPATION NUMERICAL WAVE tank WAVE simulation NUMERICAL DAMPING reduction finite difference METHOD
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基于偏振特性的下孔法剪切波到时判别问题探讨 认领
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作者 苏杰 周正华 +3 位作者 李小军 董青 李玉萍 陈柳 《岩土力学》 EI CAS CSCD 北大核心 2020年第4期1420-1428,共9页
基于偏振特征的剪切波到时判别在下孔法波速测试中被广泛应用,然而实际测试中时有发现压缩波初动出现反相的现象,因此针对压缩波不偏振而剪切波偏振的理论基础进行论证很有必要。通过三维有限元分析模型模拟了地表敲击下孔法波速测试,... 基于偏振特征的剪切波到时判别在下孔法波速测试中被广泛应用,然而实际测试中时有发现压缩波初动出现反相的现象,因此针对压缩波不偏振而剪切波偏振的理论基础进行论证很有必要。通过三维有限元分析模型模拟了地表敲击下孔法波速测试,并基于时域逐步积分动力有限元方法求解了地表正反向水平敲击下不同深度观测点振动响应。结果表明:地表水平正反向激励下,各深度观测点中与激励方向平行的水平分量中压缩波也出现反相。为进一步探讨这与实际工程的认知相悖的现象,数值模拟了荷载倾斜、探头旋转、探头倾斜等实际测试可能出现的情形。结果显示:荷载倾斜与探头倾斜的综合影响会导致正反向敲击激励下压缩波的初动相位不反相。进一步,提出了一种剪切波旅时计算新方法以减少每次敲击之间敲击角度、探头偏转和倾斜变化带来的影响,数值计算得到基于新方法求解的剪切波速接近模型介质剪切波速值,其优于利用峰-峰法和互相关法确定旅时而得到的波速结果。 展开更多
关键词 下孔法 数值模拟 偏振效应 S波 P波
无线智能家居控制系统研究 认领
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作者 侯冉冉 《智能建筑电气技术》 2020年第1期47-50,共4页
本文介绍了智能家居控制系统的基本概念,论述了其功能和用途,并对当前广泛应用的无线智能家居控制系统进行了阐述。分析了当前主流的无线智能家居控制系统采用的通信协议及其优缺点。简要论述了5G对智能家居控制系统的影响。
关键词 智能家居控制系统 无线智能家居控制系统 无线通信协议 蓝牙 WiFi Halow ZigBee Z-WAVE LoRa Thread 5G
The Relationship Between Abnormal Meiyu and Medium-Term Scale Wave Perturbation Energy Propagation Along the East Asian Subtropical Westerly Jet 认领
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作者 金荣花 杨宁 +2 位作者 孙晓晴 刘思佳 尹姗 《热带气象学报:英文版》 SCIE 2020年第2期125-136,共12页
The East Asian subtropical westerly jet(EASWJ)is one of the most important factors modulating the Meiyu rainfall in the Yangtze-Huaihe River Basin,China.This article analyzed periods of the medium-term EASWJ variation... The East Asian subtropical westerly jet(EASWJ)is one of the most important factors modulating the Meiyu rainfall in the Yangtze-Huaihe River Basin,China.This article analyzed periods of the medium-term EASWJ variation,wave packet distribution and energy propagation of Rossby waves along the EASWJ during Meiyu season,and investigated their possible influence on abnormal Meiyu rain.The results showed that during the medium-term scale atmospheric dynamic process,the evolution of the EASWJ in Meiyu season was mainly characterized by the changes of3-8 d synoptic-scale and 10-15 d low-frequency Rossby waves.The strong perturbation wave packet and energy propagation of the 3-8 d synoptic-scale and 10-15 d low-frequency Rossby waves are mostly concentrated in the East Asian region of 90°-150°E,where the two wave trains of perturbation wave packets and wave-activity flux divergence coexist in zonal and meridional directions,and converge on the EASWJ.Besides,the wave trains of perturbation wave packet and wave-activity flux divergence in wet Meiyu years are more systematically westward than those in dry Meiyu years,and they are shown in the inverse phases between each other.In wet(dry)Meiyu year,the perturbation wave packet high-value area of the 10-15 d low-frequency variability is located between the Aral Sea and the Lake Balkhash(in the northeastern part of China),while over eastern China the wave-activity flux is convergent and strong(divergent and weak),and the high-level jets are strong and southward(weak and northward).Because of the coupling of high and low level atmosphere and high-level strong(weak)divergence on the south side of the jet over the Yangtze-Huaihe River Basin,the low-level southwest wind and vertically ascending motion are strengthened(weakened),which is(is not)conducive to precipitation increase in the Yangtze-Huaihe River Basin.These findings would help to better understand the impact mechanisms of the EASWJ activities on abnormal Meiyu from the perspective of medium-term scale Rossby wave energ 展开更多
关键词 East Asian subtropical westerly jet(EASWJ) medium-term scale Rossby wave wave packet distribution energy propagation abnormal Meiyu
Mitigation of the amplitude and celerity of dam break shock wave using combination of groyne and vertical pier 认领
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作者 FAN Ji-hui GALOIE Majid MOTAMEDI Artemis 《山地科学学报:英文版》 SCIE CSCD 2020年第6期1452-1461,共10页
This paper aims to numerically investigate the impact of the combination of groynes and vertical piers on mitigating the amplitude and celerity of dam break wave-front.First,a robust numerical model based on the Finit... This paper aims to numerically investigate the impact of the combination of groynes and vertical piers on mitigating the amplitude and celerity of dam break wave-front.First,a robust numerical model based on the Finite Volume Method(FVM)with the Harten,Lax and van Leer(HLL)approximate Reimann’s solver’s technique is developed and validated with other research studies.Then many different scenarios including group of piers,group of groynes with different shapes and combination of groynes and piers are considered for dam break flow modeling.The final results showed that group of piers alone or group of groynes alone have no significant effects on the wave-front depth and celerity but,combination of L-head groyne with piers can decrease the amplitude and celerity of the dam break wavefront or flood wave.In this case,a blockage zone between the groynes and intensive backwater effects behind them were observed. 展开更多
关键词 Dam break shock wave HLL(Harten Lax and van Leer) Finite Volume Method Groyne Flood wave damping Flood management
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