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WAVE SUPERPOSITION METHOD BASED ON VIRTUAL SOURCE BOUNDARY WITH COMPLEX RADIUS VECTOR FOR SOLVING ACOUSTIC RADIATION PROBLEMS 被引量:3
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作者 XiangYu HuangYuying MaXiaoqiang 《Acta Mechanica Solida Sinica》 SCIE EI 2004年第1期12-19,共8页
By virtue of the comparability between the wave superposition method and the dynamic analysis of structures, a general format for overcoming the non-uniqueness of solution induced by the wave superposition method at t... By virtue of the comparability between the wave superposition method and the dynamic analysis of structures, a general format for overcoming the non-uniqueness of solution induced by the wave superposition method at the eigenfrequencies of the corresponding interior problems is proposed. By adding appropriate damp to the virtual source system of the wave superposition method, the unique solutions for all wave numbers can be ensured. Based on this thought, a novel method-wave superposition method with complex radius vector is constructed. Not only is the computational time of this method approximately equal to that of the standard wave superposition method, but also the accuracy is much higher compared with other correlative methods. Finally, by taking the pulsating sphere and oscillating sphere as examples, the results of calculation show that the present method can effectively overcome the non-uniqueness problem. 展开更多
关键词 virtual boundary integral equation wave superposition method wave superposition method with complex radius vector acoustic radiation virtual damp
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Nonlinear Optimization Method of Ship Floating Condition Calculation in Wave Based on Vector 被引量:4
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作者 丁宁 余建星 《China Ocean Engineering》 SCIE EI CSCD 2014年第4期471-478,共8页
Ship floating condition in regular waves is calculated. New equations controlling any ship's floating condition are proposed by use of the vector operation. This form is a nonlinear optimization problem which can be ... Ship floating condition in regular waves is calculated. New equations controlling any ship's floating condition are proposed by use of the vector operation. This form is a nonlinear optimization problem which can be solved using the penalty function method with constant coefficients. And the solving process is accelerated by dichotomy. During the solving process, the ship's displacement and buoyant centre have been calculated by the integration of the ship surface according to the waterline. The ship surface is described using an accumulative chord length theory in order to determine the displacement, the buoyancy center and the waterline. The draught forming the waterline at each station can be found out by calculating the intersection of the ship surface and the wave surface. The results of an example indicate that this method is exact and efficient. It can calculate the ship floating condition in regular waves as well as simplify the calculation and improve the computational efficiency and the precision of results. 展开更多
关键词 ship floating condition vector operation regular wave nonlinear optimization DICHOTOMY accumulativechord length
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Kinetic Flux Vector Splitting Method for the Shallow Water Wave Equations 被引量:1
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作者 施卫平 Wei Shyy 耿爱芳 《Northeastern Mathematical Journal》 CSCD 2003年第1期57-67,共11页
Based on the analogy to gas dynamics, the kinetic flux vector splitting (KFVS) method is used to stimulate the shallow water wave equations. The flux vectors of the equations are split on the basis of the local equili... Based on the analogy to gas dynamics, the kinetic flux vector splitting (KFVS) method is used to stimulate the shallow water wave equations. The flux vectors of the equations are split on the basis of the local equilibrium Maxwell-Boltzmann distribution. One dimensional examples including a dam breaking wave and flows over a ridge are calculated. The solutions exhibit second-order accuracy with no spurious oscillation. 展开更多
关键词 shallow water wave kinetic flux vector splitting total variation diminution Maxwellian distribution
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Data-driven parity-time-symmetric vector rogue wave solutions of multi-component nonlinear Schrödinger equation
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作者 Li-Jun Chang Yi-Fan Mo +1 位作者 Li-Ming Ling De-Lu Zeng 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第6期137-144,共8页
Rogue waves are a class of nonlinear waves with extreme amplitudes,which usually appear suddenly and disappear without any trace.Recently,the parity-time(PT)-symmetric vector rogue waves(RWs)of multi-component nonline... Rogue waves are a class of nonlinear waves with extreme amplitudes,which usually appear suddenly and disappear without any trace.Recently,the parity-time(PT)-symmetric vector rogue waves(RWs)of multi-component nonlinear Schrödinger equation(n-NLSE)are usually derived by the methods of integrable systems.In this paper,we utilize the multi-stage physics-informed neural networks(MS-PINNs)algorithm to derive the data-driven symmetric vector RWs solution of coupled NLS system in elliptic and X-shapes domains with nonzero boundary condition.The results of the experiment show that the multi-stage physics-informed neural networks are quite feasible and effective for multi-component nonlinear physical systems in the above domains and boundary conditions. 展开更多
关键词 nonlinear Schrödinger equation vector rogue waves deep learning numerical simulations
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NORMAL AND ABNORMAL CYLINDRICAL VECTOR WAVE FUNCTIONS AND SOME IMPORTANT CONVERSION RELATIONS
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作者 黎志坚 周学松 《Journal of Electronics(China)》 1989年第4期367-372,共6页
The normal and abnormal cylindrical vector wave functions are constructed. Some impor-tant conversion relations in circular, elliptic and parabolic cylindrical coordinate systems are discussedin detail, where the resu... The normal and abnormal cylindrical vector wave functions are constructed. Some impor-tant conversion relations in circular, elliptic and parabolic cylindrical coordinate systems are discussedin detail, where the result in circular cylindrical coordinate system is the same as the one given bythe author (1984). 展开更多
关键词 CYLINDRICAL FUNCTIONS GENERATING FUNCTIONS Piloting vector vector wave FUNCTIONS
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Person Authentication Using a New Feature Vector of the Brain Wave
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作者 Isao Nakanishi Sadanao Baba Chisei Miyamoto Shignag Li 《通讯和计算机(中英文版)》 2012年第1期101-105,共5页
关键词 身份验证 特征向量 脑电波 生物识别技术 生物认证 光计算 用户管理 验证实验
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VECTOR WAVE FUNCTION EXPANSION FOR SOLVING ELECTROMAGNETIC SCATTERING BY BURIED OBJECTS
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作者 陈景养 徐鹏根 鲁述 《Journal of Electronics(China)》 1991年第3期239-246,共8页
An analysis of solving the electromagnetic scattering by buried objects using vectorwave function expansion is presented.For expanding the boundary conditions both on the planarair-earth interface and on the spherical... An analysis of solving the electromagnetic scattering by buried objects using vectorwave function expansion is presented.For expanding the boundary conditions both on the planarair-earth interface and on the spherical surface,the conversion relations between the cylindricaland spherical vector wave functions are derived.Hence the vector wave function expansion isconveniently applied to solve this complex boundary-value problem.For the excitation of the in-cident plane wave and the dipole above the earth,the scatterlng patterns of the buried conductingand dielectric spheres are presented and discussed. 展开更多
关键词 Electromagnetic scattering BURIED objects Boundary condition vector wave function EXPANSION wave transformation
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Lax pair and vector semi-rational nonautonomous rogue waves for a coupled time-dependent coefficient fourth-order nonlinear Schrodinger system in an inhomogeneous optical fiber
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作者 Zhong Du Bo Tian +1 位作者 Qi-Xing Qu Xue-Hui Zhao 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第3期55-61,共7页
Optical fibers are seen in the optical sensing and optical fiber communication. Simultaneous propagation of optical pulses in an inhomogeneous optical fiber is described by a coupled time-dependent coefficient fourth-... Optical fibers are seen in the optical sensing and optical fiber communication. Simultaneous propagation of optical pulses in an inhomogeneous optical fiber is described by a coupled time-dependent coefficient fourth-order nonlinear Schr?dinger system, which is discussed in this paper. For such a system, we work out the Lax pair, Darboux transformation, and corresponding vector semi-rational nonautonomous rogue wave solutions. When the group velocity dispersion(GVD) and fourth-order dispersion(FOD) coefficients are the constants, we exhibit the first-and second-order vector semirational rogue waves which are composed of the four-petalled rogue waves and eye-shaped breathers. Both the width of the rogue wave along the time axis and temporal separation between the adjacent peaks of the breather decrease with the GVD coefficient or FOD coefficient. With the GVD and FOD coefficients as the linear, cosine, and exponential functions, we respectively present the first-and second-order periodic vector semi-rational rogue waves, first-and second-order asymmetry vector semi-rational rogue waves, and interactions between the eye-shaped breathers and the composite rogue waves. 展开更多
关键词 inhomogeneous optical fiber Lax pair coupled time-dependent coefficient fourth-order nonlinear Schrodinger system vector semi-rational nonautonomous rogue waves breathers
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Reduced Vector Helmholtz Wave Equation Analysis on the Wave-Number Side
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作者 Randy Ott 《Journal of Electromagnetic Analysis and Applications》 2019年第9期161-172,共12页
The resolvent helps solve a PDE defined on all of wave-number space, . Almost all electromagnetic scattering problems have been solved on the spatial side and use the spatial Green’s function approach. This work is m... The resolvent helps solve a PDE defined on all of wave-number space, . Almost all electromagnetic scattering problems have been solved on the spatial side and use the spatial Green’s function approach. This work is motivated by solving an EM problem on the Fourier side in order to relate the resolvent and the Green’s function. Methods used include Matrix Theory, Fourier Transforms, and Green’s function. A closed form of the resolvent is derived for the electromagnetic Helmholtz reduced vector wave equation, with Dirichlet boundary conditions. The resolvent is then used to derive expressions for the solution of the EM wave equation and provide Sobolev estimates for the solution. 展开更多
关键词 HELMHOLTZ em vector wave Equation Closed form of RESOLVENT SOBOLEV ESTIMATES for Solution
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Photon Structure and Wave Function from the Vector Potential Quantization
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作者 Constantin Meis 《Journal of Modern Physics》 CAS 2023年第3期311-329,共19页
A photon structure is advanced based on the experimental evidence and the vector potential quantization at a single photon level. It is shown that the photon is neither a point particle nor an infinite wave but behave... A photon structure is advanced based on the experimental evidence and the vector potential quantization at a single photon level. It is shown that the photon is neither a point particle nor an infinite wave but behaves rather like a local “wave-corpuscle” extended over a wavelength, occupying a minimum quantization volume and guided by a non-local vector potential real wave function. The quantized vector potential oscillates over a wavelength with circular left or right polarization giving birth to orthogonal magnetic and electric fields whose amplitudes are proportional to the square of the frequency. The energy  and momentum are carried by the local wave-corpuscle guided by the non-local vector potential wave function suitably normalized. 展开更多
关键词 PHOTONS Photon wave Function vector Potential Quantization Photon Electric and Magnetic Fields Photon Structure wave-Corpuscle Representation Photon “Energy-vector Potential” Equation
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Conversion Technique of Vector Wave Functions:Formulas and Applications
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作者 Xu, Penggen Lu, Shu Xu, Ying 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1997年第3期6-15,共10页
The conversion theory of vector wave function is one of important problems in electromagnetic. This paper presents a systematic treatment of the conversion technique and some applications. In this paper, the conversio... The conversion theory of vector wave function is one of important problems in electromagnetic. This paper presents a systematic treatment of the conversion technique and some applications. In this paper, the conversion relations of standard and non-standard spherical vector wave functions, standard and non-standard cylindrical vector wave functions, and spherical and cylindrical vector wave functions are developed. As an example of application of vector wave function expansion, the expansion of plane wave and dipole field in two-medium half-spaces are given. As an example of application of vector wave function conversion, the scattering patterns of buried conducting and dielectric spheres are presented. Inspection on the numerical results shows that the technique and associated programs presented in this paper are efficient. 展开更多
关键词 Boundary conditions Boundary value problems Dielectric devices Electromagnetic wave scattering Mathematical transformations vectorS
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WAVELET ANALYSIS OF THE VECTOR MAGNITUDE WAVE FOR DETECTION OF VENTRICULAR LATE POTENTIALS
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作者 Wu shuicai Lin lan Lin Jiarui(Huazhong University of Science and technology, Wuhan 430074, China) 《Chinese Journal of Biomedical Engineering(English Edition)》 1999年第3期30-31,共2页
关键词 IEEE waveLET ANALYSIS OF THE vector MAGNITUDE wave FOR DETECTION OF VENTRICULAR LATE POTENTIALS
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On a Hypothetical Vector Field Associated with the Classic Electromagnetic Wave in a Space of Four Dimensions
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作者 Leonardo Simal Moreira 《Journal of Applied Mathematics and Physics》 2020年第12期2836-2845,共10页
In two previous papers <a href="#ref1">[1]</a> and <a href="#ref2">[2]</a>, a structure for vector products in <em>n</em> dimensions was presented, and at the sa... In two previous papers <a href="#ref1">[1]</a> and <a href="#ref2">[2]</a>, a structure for vector products in <em>n</em> dimensions was presented, and at the same time it was possible to propose the existence of a vector analogous to the curl of a vector field, for a space of four dimensions. In continuation of these works, the objective is to develop, through dimensional analogy, the idea of a hypothetical vector field, associated with the classical electromagnetic wave. This hypothetical field has a possible mathematical existence only when considering a space of four dimensions. The properties of the electromagnetic wave are preserved and equations with mathematical forms analogous to those of Maxwell’s equations are presented. 展开更多
关键词 Dimensional Analogy Electromagnetic wave Four-Dimensional Space vector Fields in Four Dimensions Analog of Maxwell’s Equations
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Explicit Kinetic Flux Vector Splitting Scheme for the 2-D Shallow Water Wave Equations
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作者 施卫平 黄明游 +1 位作者 王婷 张小江 《Northeastern Mathematical Journal》 CSCD 2004年第4期457-462,共6页
Originally, the kinetic flux vector splitting (KFVS) scheme was developed as a numerical method to solve gas dynamic problems. The main idea in the approach is to construct the flux based on the microscopical descript... Originally, the kinetic flux vector splitting (KFVS) scheme was developed as a numerical method to solve gas dynamic problems. The main idea in the approach is to construct the flux based on the microscopical description of the gas. In this paper, based on the analogy between the shallow water wave equations and the gas dynamic equations, we develop an explicit KFVS method for simulating the shallow water wave equations. A 1D steady flow and a 2D unsteady flow are presented to show the robust and accuracy of the KFVS scheme. 展开更多
关键词 Kinetic flux vector splitting shallow water wave Euler equation
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基于D-Wave Advantage量子退火算法的90比特RSA整数分解研究
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作者 洪春雷 裴植 王潮 《计算机学报》 北大核心 2025年第7期1733-1748,共16页
业内认为在当前量子计算攻击密码整体进展缓慢背景下,RSA整数分解进展每提升1比特都面临挑战。根据《Nature》文章报道,2019~2023年谷歌不断改进其量子芯片,但依旧不能用于密码破译。谷歌等公司近期的研究表明:尽管亚线性量子资源方法分... 业内认为在当前量子计算攻击密码整体进展缓慢背景下,RSA整数分解进展每提升1比特都面临挑战。根据《Nature》文章报道,2019~2023年谷歌不断改进其量子芯片,但依旧不能用于密码破译。谷歌等公司近期的研究表明:尽管亚线性量子资源方法分解RSA整数可以降低量子资源的消耗,但是即使“完美的量子优化算法+Babai算法”也不足以有效地分解80比特以上的RSA整数。量子退火算法凭借其独特的量子隧穿效应,可跳出传统智能优化算法极易陷入的局部极值,快速逼近全局最优解。鉴于D-Wave Advantage的量子资源已达到5000+量子比特,本文通过使用更多的量子资源,提出一种量子退火算法结合经典密码算法分解RSA整数的混合架构。通过提高最近向量问题(Closest Vector Problem,CVP)的规模,从而提升搜索用于分解80比特以上RSA整数光滑对的能力;本文使用Block Korkin-Zolotarev(BKZ)算法对CVP的格基进行约化,获得较LLL算法更优的归约基。利用更优的归约基,Babai算法可以获得更优的CVP的解。在此基础上,本文利用量子退火算法的隧穿效应进一步优化Babai算法对CVP的求解,获得较Babai算法更优的解,从而提高光滑对的搜索效率,加速RSA整数分解。最后,本文在D-Wave Advantage上首次完成量子计算分解80比特以上的RSA整数,最大分解90比特RSA整数:629367860625666765619139989=6398047085669×98368744743281,大幅度超出富士通、洛克希德马丁公司、普渡大学的实验指标。实验结果表明:研究量子智能算法和量子位数较多的量子计算机攻击密码是有意义的,未来需要重视量子隧穿推进CVP等NP难题求解的潜力,其全局寻优能力可能成为密码攻击的关键。 展开更多
关键词 RSA整数 Block Korkin-Zolotarev算法 Babai算法 最近向量问题 量子退火 D-wave Advantage
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Instantaneous frequency and wave mode identification in a magnetosheath using few spatial points 被引量:2
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作者 Nathaniel E U Beloff N George N J 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第8期496-501,共6页
Observational data such as those obtained from the magnetosheath in the downstream of Earth's bow shock have waveforms that differ from those of sinusoidal signals. In practice, they are not even aggregates of sinuso... Observational data such as those obtained from the magnetosheath in the downstream of Earth's bow shock have waveforms that differ from those of sinusoidal signals. In practice, they are not even aggregates of sinusoidal signals. Therefore, the frequency decomposition for the data requires technique that will account for the time-varying features of the data that will lead to deduction of physical meaning of the observations. The combination of empirical mode decompo- sition (EMD) and Hilbert transform has been used for extracting the various contributing oscillatory modes (EMDs) and the instantaneous frequency determination (Hilbert transform) of every physically meaningful mode called intrinsic mode func- tion (IMF). The resulting instantaneous frequencies are used to determine instantaneous wave vectors. The combination of the instantaneous frequencies and wave vectors is useful in the identification of wave modes based on the characteristics of the waves. The results show that EMD-Hilbert can be more reliable than simple Hilbert transform alone. 展开更多
关键词 EMD-Hilbert transform instantaneous frequency and wave vector
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Simulation on effect of poloidal power spectrum on lower hybrid wave propagation 被引量:1
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作者 秦永亮 丁伯江 +2 位作者 匡光力 贾华 张立智 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第6期398-403,共6页
The coupling of lower hybrid wave to the plasma is a crucial issue for efficient current drive in tokamaks. This paper establishes a new coupling model which assumes the antenna to be a curved face and the plasma to b... The coupling of lower hybrid wave to the plasma is a crucial issue for efficient current drive in tokamaks. This paper establishes a new coupling model which assumes the antenna to be a curved face and the plasma to be a cylinder. Power spectrum considering the coupling between wave-guides in both poloidal and toroidal direction is simply estimated and discussed. The effect of the poloidal wave vector on wave propagation, power deposition and driven current is also investigated with the help of lower hybrid current drive code. Results show that the poloidal wave vector affects the ray tracing, and also has effect on power deposition and driven current. The effect of the poloidal wave vector on power deposition and driven current profile depends on plasma parameters. Preliminary studies suggest that it seems possible to control the current profile by adjusting the poloidal phase difference between the waveguide in poloidal direction. 展开更多
关键词 SIMULATION lower hybrid wave poloidal wave vector wave coupling
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Density-wave tendency from a topological nodal-line perspective
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作者 赵天伦 张亿 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第5期627-636,共10页
The understanding of density waves is a vital component of our insight into electronic quantum matters. Here, we propose an additional mosaic to the existing mechanisms such as Fermi-surface nesting, electron–phonon ... The understanding of density waves is a vital component of our insight into electronic quantum matters. Here, we propose an additional mosaic to the existing mechanisms such as Fermi-surface nesting, electron–phonon coupling, and exciton condensation. In particular, we find that certain two-dimensional(2D) spin density-wave systems are equivalent to three-dimensional(3D) Dirac nodal-line systems in the presence of a magnetic field, whose electronic structure takes the form of Dirac-fermion Landau levels and allows a straightforward analysis of its optimal filling. The subsequent minimumenergy wave vector varies over a continuous range and shows no direct connection to the original Fermi surfaces in 2D.Also, we carry out numerical calculations where the results on model examples support our theory. Our study points out that we have yet to attain a complete understanding of the emergent density wave formalism. 展开更多
关键词 density waves Dirac nodal-line optimal wave vector
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Estimating significant wave height from SAR imagery based on an SVM regression model 被引量:9
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作者 GAO Dong LIU Yongxin +2 位作者 MENG Junmin JIA Yongjun FAN Chenqing 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2018年第3期103-110,共8页
A new method for estimating significant wave height(SWH) from advanced synthetic aperture radar(ASAR) wave mode data based on a support vector machine(SVM) regression model is presented. The model is established... A new method for estimating significant wave height(SWH) from advanced synthetic aperture radar(ASAR) wave mode data based on a support vector machine(SVM) regression model is presented. The model is established based on a nonlinear relationship between σ0, the variance of the normalized SAR image, SAR image spectrum spectral decomposition parameters and ocean wave SWH. The feature parameters of the SAR images are the input parameters of the SVM regression model, and the SWH provided by the European Centre for Medium-range Weather Forecasts(ECMWF) is the output parameter. On the basis of ASAR matching data set, a particle swarm optimization(PSO) algorithm is used to optimize the input kernel parameters of the SVM regression model and to establish the SVM model. The SWH estimation results yielded by this model are compared with the ECMWF reanalysis data and the buoy data. The RMSE values of the SWH are 0.34 and 0.48 m, and the correlation coefficient is 0.94 and 0.81, respectively. The results show that the SVM regression model is an effective method for estimating the SWH from the SAR data. The advantage of this model is that SAR data may serve as an independent data source for retrieving the SWH, which can avoid the complicated solution process associated with wave spectra. 展开更多
关键词 advanced synthetic aperture radar wave mode support vector machine significant wave height
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The Potential-Vortex Theory of Electromagnetic Waves
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作者 A. K. Tomilin 《Journal of Electromagnetic Analysis and Applications》 2013年第9期347-353,共7页
An electromagnetic wave is a complex vortex and a potential process. This allows us to omit the Lorentz gauge, formulate a mathematically precise theory, and avoid physics discordances. The mechanism of distribution o... An electromagnetic wave is a complex vortex and a potential process. This allows us to omit the Lorentz gauge, formulate a mathematically precise theory, and avoid physics discordances. The mechanism of distribution of complex waves in dielectric and electrical conductive environments was described. 展开更多
关键词 Maxwell’s EQUATIONS ELECTROMAGNETIC waveS Magnetic vector POTENTIAL
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