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A New Three-Parameter Inverse Weibull Distribution with Medical and Engineering Applications
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作者 Refah Alotaibi Hassan Okasha +1 位作者 Hoda Rezk Mazen Nassar 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第5期1255-1274,共20页
The objective of this article is to provide a novel extension of the conventional inverse Weibull distribution that adds an extra shape parameter to increase its flexibility.This addition is beneficial in a variety of... The objective of this article is to provide a novel extension of the conventional inverse Weibull distribution that adds an extra shape parameter to increase its flexibility.This addition is beneficial in a variety of fields,including reliability,economics,engineering,biomedical science,biological research,environmental studies,and finance.For modeling real data,several expanded classes of distributions have been established.The modified alpha power transformed approach is used to implement the new model.The datamatches the new inverseWeibull distribution better than the inverse Weibull distribution and several other competing models.It appears to be a distribution designed to support decreasing or unimodal shaped distributions based on its parameters.Precise expressions for quantiles,moments,incomplete moments,moment generating function,characteristic generating function,and entropy expression are among the determined attributes of the new distribution.The point and interval estimates are studied using the maximum likelihood method.Simulation research is conducted to illustrate the correctness of the theoretical results.Three applications to medical and engineering data are utilized to illustrate the model’s flexibility. 展开更多
关键词 inverse weibull distribution modified alpha power transformation method MOMENTS order statistics
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Inverse Transformation of Elliptical Relative State Transition Matrix 被引量:1
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作者 Jianfeng Yin Yinrui Rao Chao Han 《International Journal of Astronomy and Astrophysics》 2014年第3期419-428,共10页
A new set of relative orbit elements (ROEs) is used to derive a new elliptical formation flying model in previous work. In-plane and out-of-plane relative motions can be completely decoupled, which benefits elliptical... A new set of relative orbit elements (ROEs) is used to derive a new elliptical formation flying model in previous work. In-plane and out-of-plane relative motions can be completely decoupled, which benefits elliptical formation design. In order to study the elliptical control strategy and perturbation effects, it is necessary to derive the inverse transformation of the relative state transition matrix based on relative orbit elements. Poisson bracket theory is used to obtain the linear transformations between the two representations: the relative orbit elements and the geocentric orbital frame. In this paper, the details of these transformations are presented. 展开更多
关键词 RELATIVE ORBIT Elements ELLIPTICAL Formation FLYING RELATIVE State Transition Matrix inverse transformation POISSON BRACKET
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~ Transform Demonstration of Dark Soliton Solutions Found by Inverse Scattering 被引量:2
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作者 LI Cun YANG Bai-Feng CAI Hao HUANG Nian-Ning 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第2X期244-248,共5页
关键词 逆散射变换 模糊孤立子 LIOUVILLE定理 理论物理
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Demonstration of Inverse Scattering Transform for DNLS Equation 被引量:1
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作者 YANG Chun-Nuan YU Jia-Lu WANG Qu-Quan HUANG Nian-Ning 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第2X期299-303,共5页
关键词 逆散射传输 单体解答方法 DNLS解答方法 物理数学
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Field measurement method for ultrasonic transducer based on inverse Abel transform
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作者 孔涛 徐春广 肖定国 《Journal of Beijing Institute of Technology》 EI CAS 2011年第2期211-215,共5页
A new reflection approach for field distribution measurement of ultrasonic transducers was investigated. Instead of a point-like reflection target (rigid sphere) or thin wires (line-like targets), a line response ... A new reflection approach for field distribution measurement of ultrasonic transducers was investigated. Instead of a point-like reflection target (rigid sphere) or thin wires (line-like targets), a line response function of experimental knife-edge distribution combined with the inverse Abel transforms was used to estimate the lateral beam distributions of ultrasonic transducers. The measurement steps were as follows:① A knife-edge was scanned perpendicularly to acoustic beam axis of the transducer using an ultrasonic C-scan system to obtain its ultrasonic image line response function, ② the transverse beam distribution was solved by the inverse Abel transforms, and ③ experiments were performed to obtain the lateral beam profiles of two transducers, with and without focus, and the results were compared with those from a hydrophone. The results showed that this method was effective for ultrasonic field measurement and could be as a substitute for hydrophone in most cases. 展开更多
关键词 ultrasonic filed measurement knife-edge distribution inverse Abel transforms
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The Role of High Precision Arithmetic in Calculating Numerical Laplace and Inverse Laplace Transforms
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作者 Zinovi Krougly Matt Davison Sid Aiyar 《Applied Mathematics》 2017年第4期562-589,共28页
In order to find stable, accurate, and computationally efficient methods for performing the inverse Laplace transform, a new double transformation approach is proposed. To validate and improve the inversion solution o... In order to find stable, accurate, and computationally efficient methods for performing the inverse Laplace transform, a new double transformation approach is proposed. To validate and improve the inversion solution obtained using the Gaver-Stehfest algorithm, direct Laplace transforms are taken of the numerically inverted transforms to compare with the original function. The numerical direct Laplace transform is implemented with a composite Simpson’s rule. Challenging numerical examples involving periodic and oscillatory functions, are investigated. The numerical examples illustrate the computational accuracy and efficiency of the direct Laplace transform and its inverse due to increasing the precision level and the number of terms included in the expansion. It is found that the number of expansion terms and the precision level selected must be in a harmonious balance in order for correct and stable results to be obtained. 展开更多
关键词 NUMERICAL LAPLACE transform NUMERICAL LAPLACE transform inversION Composite Simpson’s Rule Gaver-Stehfest Algorithm High Precision Computation
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Solving Non-Isospectral mKdV Equation and Sine-Gordon Equation Hierarchies with Self-Consistent Sources via Inverse Scattering Transform 被引量:2
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作者 李琪 张大军 陈登远 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第8期219-228,共10页
N-soliton solutions of the hierarchy of non-isospectral mKdV equation with self-consistent sources andthe hierarchy of non-isospectral sine-Gordon equation with self-consistent sources are obtained via the inverse sca... N-soliton solutions of the hierarchy of non-isospectral mKdV equation with self-consistent sources andthe hierarchy of non-isospectral sine-Gordon equation with self-consistent sources are obtained via the inverse scatteringtransform. 展开更多
关键词 逆散射变换 非等谱 源方程 自洽 层次结构 mKdV方程 方程族 孤子解
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A Regularization Method for Approximating the Inverse Laplace Transform
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作者 A. Al-Shuaibi (King Fahd University of Petroleum and Minerals, Saudi Arabia.) 《Analysis in Theory and Applications》 1997年第1期58-65,共8页
A new method for approximating the inerse Laplace transform is presented. We first change our Laplace transform equation into a convolution type integral equation, where Tikhonov regularization techniques and the Four... A new method for approximating the inerse Laplace transform is presented. We first change our Laplace transform equation into a convolution type integral equation, where Tikhonov regularization techniques and the Fourier transformation are easily applied. We finally obtain a regularized approximation to the inverse Laplace transform as finite sum 展开更多
关键词 A Regularization Method for Approximating the inverse Laplace transform
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A High-performance Low Cost Inverse Integer Transform Architecture for AVS Video Standard
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作者 李宇飞 王琴 付宇卓 《Journal of Shanghai Jiaotong university(Science)》 EI 2008年第1期116-121,共6页
A high-performance, low cost inverse integer transform architecture for advanced video standard (AVS) video coding standard was presented. An 8×8 inverse integer transform is required in AVS video system which is... A high-performance, low cost inverse integer transform architecture for advanced video standard (AVS) video coding standard was presented. An 8×8 inverse integer transform is required in AVS video system which is compute-intensive. A hardware transform is inevitable to compute the transform for the real-time application. Compared with the 4×4 transform for H.264/AVC, the 8×8 integer transform is much more complex and the coefficient in the inverse transform matrix T8 is not inerratic as that in H.264/AVC. Dividing the T8 into matrix S8 and R8, the proposed architecture is implemented with the adders and the specific CSA-trees instead of multipliers, which are area and time consuming. The architecture obtains the data processing rate up to 8 pixels per-cycle at a low cost of area. Synthesized to TSMC 0.18μm COMS process, the architecture attains the operating frequency of 300 MHz at cost of 34 252 gates with a 2-stage pipeline scheme. A reusable scheme is also introduced for the area optimization, which results in the operating frequency of 143 MHz at cost of only 19 758 gates. 展开更多
关键词 传输模式 电视 计算机技术 设计方案
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利用Inverse PCR快速筛选单个T-DNA拷贝转基因水稻植株的方法 被引量:7
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作者 章冰 黄健秋 卫志明 《实验生物学报》 CSCD 1999年第2期207-211,共5页
为了获得单个T-DNA插入拷贝的植株, 我们建立了一套利用Inverse PCR(IPCR)快速检测转基因水稻中T-DNA拷贝数的方法。用IPCR的方法可以扩增出与已知T-DNA序列相邻的水稻基因组DNA未知序列,由此推测转基因水稻植株中T-DNA的拷贝数。我们共... 为了获得单个T-DNA插入拷贝的植株, 我们建立了一套利用Inverse PCR(IPCR)快速检测转基因水稻中T-DNA拷贝数的方法。用IPCR的方法可以扩增出与已知T-DNA序列相邻的水稻基因组DNA未知序列,由此推测转基因水稻植株中T-DNA的拷贝数。我们共对15个转化株系20棵不同植株的DNA进行了IPCR检测。其中12株表现为T-DNA单拷贝插入,3株为双拷贝插入,1株为三拷贝插入。另外4株未检测到T-DNA插入拷贝。IPCR分析结果经过Southern杂交和测序的验证。 展开更多
关键词 水稻 转基因 T-DNA拷贝 inversePCR
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On Inversion of Continuous Wavelet Transform 被引量:2
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作者 Lintao Liu Xiaoqing Su Guocheng Wang 《Open Journal of Statistics》 2015年第7期714-720,共7页
This study deduces a general inversion of continuous wavelet transform (CWT) with timescale being real rather than positive. In conventional CWT inversion, wavelet’s dual is assumed to be a reconstruction wavelet or ... This study deduces a general inversion of continuous wavelet transform (CWT) with timescale being real rather than positive. In conventional CWT inversion, wavelet’s dual is assumed to be a reconstruction wavelet or a localized function. This study finds that wavelet’s dual can be a harmonic which is not local. This finding leads to new CWT inversion formulas. It also justifies the concept of normal wavelet transform which is useful in time-frequency analysis and time-frequency filtering. This study also proves a law for CWT inversion: either wavelet or its dual must integrate to zero. 展开更多
关键词 Continuous WAVELET transform Wavelet’s Dual inversION Normal WAVELET transform TIME-FREQUENCY FILTERING
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Cone-beam local reconstruction based on a Radon inversion transformation 被引量:1
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作者 汪先超 闫镔 +1 位作者 李磊 胡国恩 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第11期541-546,共6页
The local reconstruction from truncated projection data is one area of interest in image reconstruction for com- puted tomography (CT), which creates the possibility for dose reduction. In this paper, a filtered-bac... The local reconstruction from truncated projection data is one area of interest in image reconstruction for com- puted tomography (CT), which creates the possibility for dose reduction. In this paper, a filtered-backprojection (FBP) algorithm based on the Radon inversion transform is presented to deal with the three-dimensional (3D) local recon- struction in the circular geometry. The algorithm achieves the data filtering in two steps. The first step is the derivative of projections, which acts locally on the data and can thus be carried out accurately even in the presence of data trun- cation. The second step is the nonlocal Hilbert filtering. The numerical simulations and the real data reconstructions have been conducted to validate the new reconstruction algorithm. Compared with the approximate truncation resistant algorithm for computed tomography (ATRACT), not only it has a comparable ability to restrain truncation artifacts, but also its reconstruction efficiency is improved. It is about twice as fast as that of the ATRACT. Therefore, this work provides a simple and efficient approach for the approximate reconstruction from truncated projections in the circular cone-beam CT. 展开更多
关键词 computed tomography image reconstruction truncated data Radon inversion transform
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The Numerical Method of Inversion for the Interior Radon Transform 被引量:1
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作者 WANG Jin ping, DU Jin yuan College of Mathematics and Computer Science, Wuhan University ,Wuhan 430072, China 《Wuhan University Journal of Natural Sciences》 CAS 2000年第2期143-146,共4页
The interior Radon transform arises from a limited data problem in computerized tomography. The corresponding operator R is investigated as a mapping between wightedL 2-spaces. Our result is the explicit construction ... The interior Radon transform arises from a limited data problem in computerized tomography. The corresponding operator R is investigated as a mapping between wightedL 2-spaces. Our result is the explicit construction of a singular value decomposition for R. This immediately leads to an inversion formula by series expansion and range characterizations. 展开更多
关键词 Key words the interior Radon transform EIGENPROBLEM inversION
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A three-dimensional transient electromagnetic data inversion method based on a time–frequency transformation 被引量:1
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作者 Yang Yun-Jian Wang Xu-Ben +2 位作者 Liu Xue-Jun Mi Xiao-Li Mao Lifeng 《Applied Geophysics》 SCIE CSCD 2020年第3期361-376,共16页
Herein,a three-dimensional(3D)inversion method in the frequency domain based on a time–frequency transformation was developed to improve the efficiency of the 3D inversion of transient electromagnetic(TEM)data.The Fo... Herein,a three-dimensional(3D)inversion method in the frequency domain based on a time–frequency transformation was developed to improve the efficiency of the 3D inversion of transient electromagnetic(TEM)data.The Fourier transform related to the electromagnetic response in the frequency and time domains becomes a sine or cosine transform under the excitation of downward-step current.We established a transformation matrix based on the digital fi ltering calculation for the sine transform,and then the frequency domain projection of the TEM data was determined from the linear transformation system using the smoothing constrained least squares inversion method,in which only the imaginary part was used to maintain the TEM data transformation equivalence in the bidirectional projection.Thus,the time-domain TEM inversion problem was indirectly and effectively solved in the frequency domain.In the 3D inversion of the transformed frequency-domain data,the limited-memory Broyden–Fletcher–Goldfarb–Shannoquasi–Newton(L-BFGS)method was used and modifi ed with a restart strategy to adjust the regularization parameter when the algorithm tended to a local minimum.Synthetic data tests showed that our domain transformation method can stably project the TEM data into the frequency domain with very high accuracy;furthe rmore,the 3D inversion of the transformed frequency-domain data is stable,can be used to recover the real resistivity model with an acceptable effi ciency. 展开更多
关键词 Transient electromagnetic method TEM digital filtering time-frequency transformation 3D EM forward 3D EM inversion
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Gravity compression forward modeling and multiscale inversion based on wavelet transform 被引量:4
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作者 Sun Si-Yuan Yin Chang-Chun +2 位作者 Gao Xiu-He Liu Yun-He Ren Xiu-Yan 《Applied Geophysics》 SCIE CSCD 2018年第2期342-352,365,共12页
在三维的严肃倒置的主要问题是解决方案的非唯一和大数据集合的高计算的费用。最小化高计算的费用,我们建议一个新排序方法在使用小浪变换以前减少变化和敏感矩阵的高频率。因而,敏感矩阵的稀少和压缩比率象向前建模的精确性一样被改... 在三维的严肃倒置的主要问题是解决方案的非唯一和大数据集合的高计算的费用。最小化高计算的费用,我们建议一个新排序方法在使用小浪变换以前减少变化和敏感矩阵的高频率。因而,敏感矩阵的稀少和压缩比率象向前建模的精确性一样被改进。而且,记忆存储要求被减少,向前建模与未压缩的前面的建模相比被加速。向前当模特儿的结果建议敏感矩阵的压缩比率能是超过 300。而且,多尺度的倒置基于小浪变换被用于严肃倒置。由把严肃倒置分解成不同规模的 subproblems,当多尺度的数据被考虑,严肃倒置的非唯一和稳定性被改进。最后,我们在模仿并且测量的数据上使用了常规集中的倒置和多尺度的倒置表明建议严肃倒置方法的有效性。 展开更多
关键词 小浪变换 矩阵压缩 多尺度的倒置 向前当模特儿的严肃
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GENERALIZED WAVELETS AND INVERSION OF THE RADON TRANSFORM ON THE LAGUERRE HYPERGROUP 被引量:1
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作者 Bai Linglan He Jianxun (Nanjing Normal University, China) 《Approximation Theory and Its Applications》 2002年第4期55-69,共15页
Let X=Rn +×R denote the underlying manifold of polyradial functions on the Heisenberg group H n. We construct a generalized translation on X=Rn +×R, and establish the Plancherel formula on L2(X,dμ). Usin... Let X=Rn +×R denote the underlying manifold of polyradial functions on the Heisenberg group H n. We construct a generalized translation on X=Rn +×R, and establish the Plancherel formula on L2(X,dμ). Using the Gelfand transform we give the condition of generalized wavelets on L2(X,dμ). Moreover, we show the reconstruction formulas for wavelet packet trnasforms and an inversion formula of the Radon transform on X. 展开更多
关键词 MATH GENERALIZED WAVELETS AND inversION OF THE RADON transform ON THE LAGUERRE HYPERGROUP
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Inverse Computation and the Universal Resolving Algorithm
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作者 Sergei Abramov 1, Robert Glück 2 1 Program Systems Institute Russian Academy of Sciences, RU 152140 Pereslavl Zalessky, Russia 2 PRESTO,JST & Institute for Software Production Technology, Waseda University, Tokyo 169 8555, Japan 《Wuhan University Journal of Natural Sciences》 CAS 2001年第Z1期31-45,共15页
We survey fundamental concepts for inverse programming and then present the Universal Resolving Algorithm, an algorithm for inverse computation in a first order, functional programming language. We discuss the key co... We survey fundamental concepts for inverse programming and then present the Universal Resolving Algorithm, an algorithm for inverse computation in a first order, functional programming language. We discuss the key concepts of the algorithm, including a three step approach based on the notion of a perfect process tree, and demonstrate our implementation with several examples of inverse computation. 展开更多
关键词 inverse programming perfect process tree program transformation inverse interpretation program inversion functional languages
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Inversion of receiver function by wavelet transformation
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作者 吴庆举 田小波 +2 位作者 张乃铃 李桂银 曾融生 《Acta Seismologica Sinica(English Edition)》 CSCD 2003年第6期616-623,共8页
A new method for receiver function inversion by wavelet transformation is presented in this paper. Receiver func-tion is expanded to different scales with different resolution by wavelet transformation. After an initi... A new method for receiver function inversion by wavelet transformation is presented in this paper. Receiver func-tion is expanded to different scales with different resolution by wavelet transformation. After an initial model be-ing taken, a generalized least-squares inversion procedure is gradually carried out for receiver function from low to high scale, with the inversion result for low order receiver function as the initial model for high order. A neighborhood containing the global minimum is firstly searched from low scale receiver function, and will gradu-ally focus at the global minimum by introducing high scale information of receiver function. With the gradual ad-dition of high wave-number to smooth background velocity structure, wavelet transformation can keep the inver-sion result converge to the global minimum, reduce to certain extent the dependence of inversion result on the initial model, overcome the nonuniqueness of generalized least-squares inversion, and obtain reliable crustal and upper mantle velocity with high resolution. 展开更多
关键词 receiver function wavelet transformation waveform inversion
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NUMERICAL INVERSION OF MULTIDIMENSIONAL LAPLACE TRANSFORMS USING MOMENT METHODS 被引量:1
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作者 王泽文 徐定华 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 2005年第3期267-276,共10页
This paper develops a numerical method to invert multi-dimensional Laplace transforms. By a variable transform, Laplace transforms are converted to multi-dimensional Hansdorff moment problems so that the numerical sol... This paper develops a numerical method to invert multi-dimensional Laplace transforms. By a variable transform, Laplace transforms are converted to multi-dimensional Hansdorff moment problems so that the numerical solution can be achieved. Stability estimation is also obtained. Numerical simulations show the efficiency and practicality of the method. 展开更多
关键词 数字倒置 多维Laplace变换 病态问题 数字计算 矩问题
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The Numerical Inversion of the Laplace Transform in a Multi-Precision Environment
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作者 Colin L. Defreitas Steve J. Kane 《Applied Mathematics》 2022年第5期401-418,共18页
This paper examines the performance of five algorithms for numerically inverting the Laplace transform, in standard, 16-digit and multi-precision environments. The algorithms are taken from three of the four main clas... This paper examines the performance of five algorithms for numerically inverting the Laplace transform, in standard, 16-digit and multi-precision environments. The algorithms are taken from three of the four main classes of numerical methods used to invert the Laplace transform. Because the numerical inversion of the Laplace transform is a perturbed problem, rounding errors which are generated in numerical approximations can adversely affect the accurate reconstruction of the inverse transform. This paper demonstrates that working in a multi-precision environment can substantially reduce these errors and the resulting perturbations exist in transforming the data from the s-space into the time domain and in so doing overcome the main drawback of numerically inverting the Laplace transform. Our main finding is that both the Talbot and the accelerated Gaver functionals perform considerably better in a multi-precision environment increasing the advantages of using Laplace transform methods over time-stepping procedures in solving diffusion and more generally parabolic partial differential equations. 展开更多
关键词 Laplace transform PERTURBATION Numerical inversion Multi-Precision Stehfest Talbot
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