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New Asymptotic Results on Fermat-Wiles Theorem
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作者 Kimou Kouadio Prosper Kouakou Kouassi Vincent Tanoé François 《Advances in Pure Mathematics》 2024年第6期421-441,共21页
We analyse the Diophantine equation of Fermat xp yp = zp with p > 2 a prime, x, y, z positive nonzero integers. We consider the hypothetical solution (a, b, c) of previous equation. We use Fermat main divisors, Dio... We analyse the Diophantine equation of Fermat xp yp = zp with p > 2 a prime, x, y, z positive nonzero integers. We consider the hypothetical solution (a, b, c) of previous equation. We use Fermat main divisors, Diophantine remainders of (a, b, c), an asymptotic approach based on Balzano Weierstrass Analysis Theorem as tools. We construct convergent infinite sequences and establish asymptotic results including the following surprising one. If z y = 1 then there exists a tight bound N such that, for all prime exponents p > N , we have xp yp zp. 展开更多
关键词 Fermat’s Last theorem Fermat-Wiles theorem Kimou’s Divisors Diophantine Quotient Diophantine Remainders Balzano Weierstrass Analysis theorem
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A hybrid method integrating Green's function Monte Carlo and projected entangled pair states
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作者 He-Yu Lin Rong-Qiang He +1 位作者 Yibin Guo Zhong-Yi Lu 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第11期75-81,共7页
This paper introduces a hybrid approach combining Green’s function Monte Carlo(GFMC)method with projected entangled pair state(PEPS)ansatz.This hybrid method regards PEPS as a trial state and a guiding wave function ... This paper introduces a hybrid approach combining Green’s function Monte Carlo(GFMC)method with projected entangled pair state(PEPS)ansatz.This hybrid method regards PEPS as a trial state and a guiding wave function in GFMC.By leveraging PEPS’s proficiency in capturing quantum state entanglement and GFMC’s efficient parallel architecture,the hybrid method is well-suited for the accurate and efficient treatment of frustrated quantum spin systems.As a benchmark,we applied this approach to study the frustrated J_(1)–J_(2) Heisenberg model on a square lattice with periodic boundary conditions(PBCs).Compared with other numerical methods,our approach integrating PEPS and GFMC shows competitive accuracy in the performance of ground-state energy.This paper provides systematic and comprehensive discussion of the approach of our previous work[Phys.Rev.B 109235133(2024)]. 展开更多
关键词 projected entangled pair states greens function Monte Carlo frustrated J_(1)-J_(2)Heisenberg model
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Implementation of the Integrated Green’s Function Method for 3D Poisson’s Equation in a Large Aspect Ratio Computational Domain
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作者 Ji Qiang Chad Mitchell +1 位作者 Remi Lehe Arianna Formenti 《Journal of Software Engineering and Applications》 2024年第9期740-749,共10页
The solution of Poisson’s Equation plays an important role in many areas, including modeling high-intensity and high-brightness beams in particle accelerators. For the computational domain with a large aspect ratio, ... The solution of Poisson’s Equation plays an important role in many areas, including modeling high-intensity and high-brightness beams in particle accelerators. For the computational domain with a large aspect ratio, the integrated Green’s function method has been adopted to solve the 3D Poisson equation subject to open boundary conditions. In this paper, we report on the efficient implementation of this method, which can save more than a factor of 50 computing time compared with the direct brute force implementation and its improvement under certain extreme conditions. 展开更多
关键词 greens Function Poisson Equation Particle Accelerator
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Small Modular Solutions to Fermat’s Last Theorem
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作者 Thomas Beatty 《Advances in Pure Mathematics》 2024年第10期797-805,共9页
The proof by Andrew Wiles of Fermat’s Last Theorem in 1995 resolved the existence question for non-trivial solutions in integers x,y,zto the equation xn+yn=znfor n>2. There are none. Surprisingly, there are infini... The proof by Andrew Wiles of Fermat’s Last Theorem in 1995 resolved the existence question for non-trivial solutions in integers x,y,zto the equation xn+yn=znfor n>2. There are none. Surprisingly, there are infinitely many solutions if the problem is recast in terms of modular arithmetic. Over a hundred years ago Issai Schur was able to show that for any n there is always a sufficiently large prime p0such that for all primes p≥p0the congruence xn+yn≡zn(modp)has a non-trivial solution. Schur’s argument wasnon-constructive, and there is no systematic method available at present to construct specific examples for small primes. We offer a simple method for constructing all possible solutions to a large class of congruences of this type. 展开更多
关键词 Fermat’s Last theorem Modular Arithmetic CONGRUENCEs Prime Numbers Primitive Roots Indices Ramsey Theory schur’s Lemma in Ramsey Theory
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THE GAUSS–GREEN THEOREM IN CLIFFORD ANALYSIS AND ITS APPLICATIONS
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作者 罗纬宇 杜金元 《Acta Mathematica Scientia》 SCIE CSCD 2015年第1期235-254,共20页
In this article, we establish the Gauss Green type theorems for Clifford-valued functions in Clifford analysis. The boundary conditions in theorems obtained are very general by using the geometric measure theoretic me... In this article, we establish the Gauss Green type theorems for Clifford-valued functions in Clifford analysis. The boundary conditions in theorems obtained are very general by using the geometric measure theoretic method. The Cauchy-Pompeiu formula for Clifford-valued functions under the weak condition will be derived as their simple application. Furthermore, Cauchy formula for monogenic functions under the weak condition is derived directly from the Cauchy-Pompeiu formula. 展开更多
关键词 Gauss green theorem Cauchy's theorem Cauchy-Pompeiu formula Clifford analysis Geometric measure theory
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Spectral Theorem of Many-Body Green's Functions When Complex Eigenvalues Appear
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作者 WANG Huai-Yu 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第5期931-937,共7页
In this paper, an extended spectral theorem is given, which enables one to calculate the correlation functions when complex eigenvalues appear. To do so, a Fourier transformation with a complex argument is utilized. W... In this paper, an extended spectral theorem is given, which enables one to calculate the correlation functions when complex eigenvalues appear. To do so, a Fourier transformation with a complex argument is utilized. We treat all the Matsbara frequencies, including Fermionic and Bosonic frequencies, on an equal footing. It is pointed out that when complex eigenvalues appear, the dissipation of a system cannot simply be ascribed to the pure imaginary part of the Green function. Therefore, the use of the name fluctuation-dissipation theorem should be careful. 展开更多
关键词 spectral theorem many-body greens functions correlation functions complex eigenvalues
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Whole Perfect Vectors and Fermat’s Last Theorem
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作者 Ramon Carbó-Dorca 《Journal of Applied Mathematics and Physics》 2024年第1期34-42,共9页
A naïve discussion of Fermat’s last theorem conundrum is described. The present theorem’s proof is grounded on the well-known properties of sums of powers of the sine and cosine functions, the Minkowski norm de... A naïve discussion of Fermat’s last theorem conundrum is described. The present theorem’s proof is grounded on the well-known properties of sums of powers of the sine and cosine functions, the Minkowski norm definition, and some vector-specific structures. 展开更多
关键词 Fermat’s Last theorem Whole Perfect Vectors sine and Cosine Functions Natural and Rational Vectors Fermat Vectors
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Existence of Monotone Positive Solution for a Fourth-Order Three-Point BVP with Sign-Changing Green’s Function
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作者 Junrui Yue Yun Zhang Qingyue Bai 《Open Journal of Applied Sciences》 2024年第1期63-69,共7页
This paper is concerned with the following fourth-order three-point boundary value problem , where , we discuss the existence of positive solutions to the above problem by applying to the fixed point theory in cones a... This paper is concerned with the following fourth-order three-point boundary value problem , where , we discuss the existence of positive solutions to the above problem by applying to the fixed point theory in cones and iterative technique. 展开更多
关键词 Fourth-Order Three-Point Boundary Value Problem sign-Changing greens Function Fixed Point Index Iterative Technique Monotone Positive solution EXIsTENCE
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Singularity-free Green's function for EM sources embedded in a stratified medium 被引量:3
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作者 翁爱华 刘云鹤 +1 位作者 殷长春 贾定宇 《Applied Geophysics》 SCIE CSCD 2016年第1期25-36,217,218,共14页
We present a method to unify the calculation of Green's functions for an electromagnetic(EM) transmitting source embedded in a homogeneous stratified medium.A virtual interface parallel to layer interfaces is intro... We present a method to unify the calculation of Green's functions for an electromagnetic(EM) transmitting source embedded in a homogeneous stratified medium.A virtual interface parallel to layer interfaces is introduced through the source location.The potentials for Green's function are derived by decomposing the partial wave solutions to Helmholtz's equations into upward and downward within boundaries.The amplitudes of the potentials in each stratum are obtained recursively from the initial amplitudes at the source level.The initial amplitudes are derived by coupling with the transmitting sources and following the discontinuity of the tangential electric and magnetic fields at the source interface.Only the initial terms are related to the transmitting sources and thus need to be modified for different transmitters,whereas the kernel connected with the stratified media stays unchanged.Hence,the present method can be easily applied to EM transmitting sources with little modification.The application of the proposed method to the marine controlled-source electromagnetic method(MCSEM) demonstrates its simplicity and flexibility. 展开更多
关键词 EM Marine EM greens function stratified medium sINGULARITY
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The Green's function of the harmonic horizontal force applied at the interior of the saturated half-space soil 被引量:10
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作者 陆建飞 王建华 沈为平 《地震学报》 CSCD 北大核心 2001年第2期185-191,共7页
By using integral transform methods, the Green(s functions of horizontal harmonic force applied at the interior of the saturated half-space soil are obtained in the paper. The general solutions of the Biot dynamic equ... By using integral transform methods, the Green(s functions of horizontal harmonic force applied at the interior of the saturated half-space soil are obtained in the paper. The general solutions of the Biot dynamic equations in frequency domain are established through the use of Hankel integral transforms technique. Utilizing the above- mentioned general solutions, and the boundary conditions of the surface of the half-space and the continuous conditions at the plane of the horizontal force, the solutions of the boundary value problem can be determined. By the numerical inverse Hankel transforms method, the Green(s functions of the harmonic horizontal force are obtainable. The degenerate case of the results deduced from this paper agrees well with the known results. Two numerical examples are given in the paper. 展开更多
关键词 BIOT理论 HANKEL变换 green函数 非轴对称 非饱和土 简谐水平力
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SYBR GreenⅠ实时荧光PCR检测食品中转基因成分方法的初步建立 被引量:2
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作者 王燕梅 刘衡川 梁疆莉 《江苏预防医学》 CAS 2009年第1期12-14,共3页
目的:建立SYBR GreenⅠ实时荧光PCR方法检测食品中转基因成分35S启动子和NOS终止子,并对样品进行检测。方法:以大豆Lectin基因为内源性基因,以转基因食品中常用的花椰菜花叶病毒启动子(Ca MV35S)和根癌农杆菌终止子(NOS)基因为目标基因... 目的:建立SYBR GreenⅠ实时荧光PCR方法检测食品中转基因成分35S启动子和NOS终止子,并对样品进行检测。方法:以大豆Lectin基因为内源性基因,以转基因食品中常用的花椰菜花叶病毒启动子(Ca MV35S)和根癌农杆菌终止子(NOS)基因为目标基因,设计并合成3对特异性引物,优化反应条件,使用SYBR GreenⅠ染料实时荧光PCR检测35S启动子和NOS终止子,并做熔解曲线分析。同时利用该方法对胡萝卜、青豆、玉米、马铃薯等实际样品进行检测。结果:运用该方法检测8份样品,有4份检出35S基因和NOS基因成分。结论:SYBR GreenⅠ实时荧光PCR方法能有效检测出35S和NOS两种转基因成分,简便、快速。 展开更多
关键词 转基因 sYBR green Ⅰ实时荧光PCR 35s NOs
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纳米分子器件量子传导中的Green's Function模型
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作者 王利光 李勇 +1 位作者 郁鼎文 Katsunori TAGAMI 《黑龙江大学自然科学学报》 CAS 北大核心 2005年第2期213-215,共3页
将纳米分子器件的电极和分子本体作为一个系统,考虑到入射电子在原子电极和分子本体中的传导,在电极与分子之间界面上的透射的量子状态,在满足Fisher-Lee关系式的基础上,一个新型的Green’sFunction被设计出来。这一理论模型把三个区域... 将纳米分子器件的电极和分子本体作为一个系统,考虑到入射电子在原子电极和分子本体中的传导,在电极与分子之间界面上的透射的量子状态,在满足Fisher-Lee关系式的基础上,一个新型的Green’sFunction被设计出来。这一理论模型把三个区域上的不同量子状态完整地表达在一个方程式里,符合物理学基本原理,可以系统地用来研究纳米分子器件的量子传导特性。 展开更多
关键词 纳米分子器件 量子传导 greens FUNCTION
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(S,T)-双系上的Green′s关系及其稳定性
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作者 高振林 赵根灵 《上海理工大学学报》 CAS 北大核心 2010年第4期385-390,共6页
建立(S,T)-双系M上的Green′s关系理论.利用其基本性质讨论M的稳定性.将M的稳定性应用到半群上使得半群理论中的平行经典结果成为其特例,而有些却成为半群理论中的新结果.
关键词 (s T)-双系 green′s关系 (s T)-子系 稳定(s T)-双系
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层次化的K.Fan’s Theorem
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作者 朱凤梅 李令强 孟广武 《聊城大学学报(自然科学版)》 2010年第2期1-3,89,共4页
在L-拓扑空间中,对任意LF集,我们利用层次化的K.Fan’s Theorem定义了一种层次连通并研究了其基本性质.
关键词 L-拓扑空间 层次连通 K.Fan’s theorem
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猪德尔塔冠状病毒SYBR Green Ⅰ实时荧光定量PCR方法的建立及应用 被引量:7
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作者 杜倩 汪伟 +7 位作者 韩知晓 孔子荣 辛佳亮 闭璟珊 曹亮 孙文超 胡传活 郑敏 《中国动物传染病学报》 CAS 北大核心 2021年第2期15-21,共7页
为建立一种猪德尔塔病毒(PDCoV)的快速检测方法,本研究根据NCBI公布的PDCoV序列设计了1对特异性引物,利用RT-PCR方法扩增PDCoV的S基因,将其连接至pMD19-T载体上,以构建正确的重组质粒作为标准品,建立SYBR Green Ⅰ实时荧光定量PCR检测方... 为建立一种猪德尔塔病毒(PDCoV)的快速检测方法,本研究根据NCBI公布的PDCoV序列设计了1对特异性引物,利用RT-PCR方法扩增PDCoV的S基因,将其连接至pMD19-T载体上,以构建正确的重组质粒作为标准品,建立SYBR Green Ⅰ实时荧光定量PCR检测方法,并对该方法的敏感性、特异性及重复性进行了验证分析。结果显示:该检测方法在标准品浓度为6.26×10^(1)~6.26×10^(8)copies/μL范围内呈良好线性关系,其相关性为0.999,斜率为-4.312;灵敏度良好,检测下限可达6.26×10^(1)copies/μL;特异性良好,对PEDV和TGEV两种猪常见病原均无特异性扩增;重复性好,组内和组间变异系数均小于2.0%;利用该方法对43份临床样品进行检测,PDCoV阳性率为4.6%。结果表明,本研究成功建立了PDCoV的SYBR GreenⅠ实时荧光定量PCR检测方法,为PDCoV快速灵敏的诊断奠定了坚实基础。 展开更多
关键词 猪德尔塔冠状病毒 s基因 sYBR greenⅠ实时荧光定量PCR
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基于S-R和分解定理的二维几何非线性问题的虚单元法求解
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作者 江巍 尹豪 +3 位作者 吴剑 汤艳春 李坤鹏 郑宏 《工程力学》 EI CSCD 北大核心 2024年第8期23-35,共13页
应变-旋转(Strain-Rotation,S-R)和分解定理为分析几何非线性问题提供了合理可靠的理论基础,但用有限元求解时会遇到大变形发生后的网格畸变问题。近年提出的虚单元法(Virtual element method,VEM)适用于一般的多边形网格,因此,该文尝... 应变-旋转(Strain-Rotation,S-R)和分解定理为分析几何非线性问题提供了合理可靠的理论基础,但用有限元求解时会遇到大变形发生后的网格畸变问题。近年提出的虚单元法(Virtual element method,VEM)适用于一般的多边形网格,因此,该文尝试使用一阶虚单元求解基于S-R和分解定理的二维几何非线性问题,以克服网格畸变的影响。基于重新定义的多项式位移空间基函数,推演获得一阶虚单元分析线弹性力学问题时允许位移空间向多项式位移空间的投影表达式;按照虚单元法双线性格式的计算规则,分析处理基于更新拖带坐标法和势能率原理的增量变分方程;进而建立离散系统方程及其矩阵表达形式,并编制MATLAB求解程序;采用常规多边形网格和畸变网格,应用该文算法分析均布荷载下的悬臂梁和均匀内压下的厚壁圆筒变形。结果与已有文献和ANSYS软件的对比表明:该文算法在两种网格中均可有效执行且具备足够数值精度。总体该文算法为基于S-R和分解定理的二维几何非线性问题求解提供了一种鲁棒方法。 展开更多
关键词 s-R和分解定理 虚单元法 几何非线性 网格畸变 多边形网格
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禽呼肠孤病毒SYBR Green Ⅰ荧光定量PCR检测方法的建立 被引量:9
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作者 李天芝 于新友 +1 位作者 王金良 沈志强 《家禽科学》 2015年第10期10-14,共5页
为了建立禽呼肠孤病毒(ARV)快速、敏感的检测方法。本研究利用RT-PCR技术扩增出ARV S1基因中298bp的保守序列,并克隆到p MD18-T载体中作为标准品制作标准曲线,建立了ARV的SYBR Green Ⅰ荧光定量PCR检测方法。该方法检测灵敏度可达4.8... 为了建立禽呼肠孤病毒(ARV)快速、敏感的检测方法。本研究利用RT-PCR技术扩增出ARV S1基因中298bp的保守序列,并克隆到p MD18-T载体中作为标准品制作标准曲线,建立了ARV的SYBR Green Ⅰ荧光定量PCR检测方法。该方法检测灵敏度可达4.8×101拷贝,与NDV、AIV、IBV、IBDV、ALV、REV均不发生交叉反应,具有良好的特异性和重复性。结果表明,建立的实时荧光定量PCR具有特异、敏感、快速、定量、重复性好等优点,可用于临床ARV的检测。 展开更多
关键词 禽呼肠孤病毒 s1基因 sYBR green 荧光定量PCR
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半环上的Green's-L关系 被引量:2
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作者 包强 梅永刚 邵海琴 《科学技术与工程》 2007年第7期1416-1418,共3页
由半环的理想出发,给出了半环上的Green’s-L关系L与其乘法半群的Green’s-L关系■相等的条件,探讨了满足■=L的半环的性质,并给出了单元素■-类的刻画。
关键词 半环 greens-关系 理想
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VECTORIAL EKELAND'S VARIATIONAL PRINCIPLE WITH A W-DISTANCE AND ITS EQUIVALENT THEOREMS 被引量:8
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作者 丘京辉 李博 贺飞 《Acta Mathematica Scientia》 SCIE CSCD 2012年第6期2221-2236,共16页
By using the properties of w-distances and Gerstewitz's functions, we first give a vectorial Takahashi's nonconvex minimization theorem with a w-distance. From this, we deduce a general vectorial Ekeland's variatio... By using the properties of w-distances and Gerstewitz's functions, we first give a vectorial Takahashi's nonconvex minimization theorem with a w-distance. From this, we deduce a general vectorial Ekeland's variational principle, where the objective function is from a complete metric space into a pre-ordered topological vector space and the perturbation contains a w-distance and a non-decreasing function of the objective function value. From the general vectorial variational principle, we deduce a vectorial Caristfs fixed point theorem with a w-distance. Finally we show that the above three theorems are equivalent to each other. The related known results are generalized and improved. In particular, some conditions in the theorems of [Y. Araya, Ekeland's variational principle and its equivalent theorems in vector optimization, J. Math. Anal. Appl. 346(2008), 9-16] are weakened or even completely relieved. 展开更多
关键词 Takahashi's minimization theorem Ekeland's variational principle Caristi'sfixed point theorem Gerstewitz's function w-distance
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Study on Characteristics of 3-D Translating-Pulsating Source Green Function of Deep-Water Havelock Form and Its Fast Integration Method 被引量:19
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作者 许勇 董文才 《China Ocean Engineering》 SCIE EI 2011年第3期365-380,共16页
The singularities, oscillatory performances and the contributing factors to the 3-'D translating-pulsating source Green function of deep-water Havelock form which consists of a local disturbance part and a far-field ... The singularities, oscillatory performances and the contributing factors to the 3-'D translating-pulsating source Green function of deep-water Havelock form which consists of a local disturbance part and a far-field wave-like part, are analyzed systematically. Relative numerical integral methods about the two parts are presented in this paper. An improved method based on LOBATTO rule is used to eliminate singularities caused respectively by infinite discontinuity and jump discontinuous node from the local disturbance part function, which makes the improvement of calculation efficiency and accuracy possible. And variable substitution is applied to remove the singularity existing at the end of the integral interval of the far-field wave-like part function. Two auxiliary techniques such as valid interval calculation and local refinement of integral steps technique in narrow zones near false singularities are applied so as to avoid unnecessary integration of invalid interval and improve integral accordance. Numerical test results have proved the efficiency and accuracy in these integral methods that thus can be applied to calculate hydrodynamic performance of floating structures moving in waves. 展开更多
关键词 translating-pulsating source greens function singularity highly oscillatory function integration method
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