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Pricing power option under NIG model using fast Fourier transform
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作者 LI Cui-xiang WANG Meng-na +1 位作者 LIU Hui-li LI Wen-han 《Applied Mathematics(A Journal of Chinese Universities)》 2025年第2期327-342,共16页
The aim of this paper is to price power option with its underlying asset price following exponential normal inverse gaussian(NIG)process.We first find the risk neutral equivalent martingale measure Q by Esscher transf... The aim of this paper is to price power option with its underlying asset price following exponential normal inverse gaussian(NIG)process.We first find the risk neutral equivalent martingale measure Q by Esscher transform.Then,using the Fourier transform and its inverse,we derive the analytical pricing formulas of power options which are expressed in the form of Fourier integral.In addition,the fast Fourier transform(FFT)algorithm is applied to calculate these pricing formulas.Finally,Shangzheng 50ETF options are chosen to test our results.Estimating the parameters in NIG process by maximum likelihood method,we show that the NIG prices are much closer to market prices than the Black-Scholes-Merton(BSM)ones. 展开更多
关键词 power option NIG process Esscher transform fourier transform FFT algorithm
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Color Fourier single-pixel imaging with random color filter array
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作者 Jialiang Chen Wei Zhu +1 位作者 Le Wang Shengmei Zhao 《Chinese Physics B》 2025年第9期250-259,共10页
Color Fourier single-pixel imaging(FSI)enables efficient spectral and spatial imaging.Here,we propose a Fourier single-pixel imaging scheme with a random color filter array(FSI-RCFA).The proposed method employs a rand... Color Fourier single-pixel imaging(FSI)enables efficient spectral and spatial imaging.Here,we propose a Fourier single-pixel imaging scheme with a random color filter array(FSI-RCFA).The proposed method employs a random color filter array(RCFA)to modulate Fourier patterns.A three-step phase-shifting technique reconstructs the Fourier spectrum,followed by an RCFA-based demosaicing algorithm to recover color images.Compared to traditional color FSI based on Bayer color filter array schemes(FSI-BCFA),our approach achieves superior separation between chrominance and luminance components in the frequency domain.Simulation results demonstrate that the FSI-RCFA method achieves a lower mean squared error(MSE),a higher peak signal-to-noise ratio(PSNR),and superior noise resistance compared to FSI-BCFA,while enabling direct single-channel pixel measurements for targeted applications such as agricultural defect detection. 展开更多
关键词 color single-pixel imaging fourier single-pixel imaging random color filter array demosaicing algorithm noise resistance
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IMPROVED FOURIER ALGORITHM FOR CORRECTING POWER SYSTEM FREQUENCY DEVIATION 被引量:1
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作者 姜惠兰 杨维 +2 位作者 徐建强 刘梅 仇晓锋 《Transactions of Tianjin University》 EI CAS 2001年第3期192-196,共5页
On the basis of high precision requirement for input signals in the power system protection and control system,this paper,only for the influence of power system frequency deviation on extracting fundamental harmonic,s... On the basis of high precision requirement for input signals in the power system protection and control system,this paper,only for the influence of power system frequency deviation on extracting fundamental harmonic,studies the amplitude error of Fourier algorithm,presents a method of correcting frequency deviation,and further derives the formulas of improved Fourier algorithm.The simulation results verified the effectiveness of the algorithm,it not only can greatly weaken the influence of frequency deviation,but also increase the precision of the power system protection and control.As a result the study in this paper has practical application value. 展开更多
关键词 power system protection and control frequency deviation fourier algorithm
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Anti-aliasing nonstationary signals detecion algorithm based on interpolation in the frequency domain using the short time Fourier transform 被引量:7
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作者 Bian Hailong Chen Guangju 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第3期419-426,共8页
To eliminate the aliasing that appeared during the measurement of multi-components nonstationary signals, a novel kind of anti-aliasing algorithm based on the short time Fourier transform (STFT) is brought forward. ... To eliminate the aliasing that appeared during the measurement of multi-components nonstationary signals, a novel kind of anti-aliasing algorithm based on the short time Fourier transform (STFT) is brought forward. First the physical essence of aliasing that occurs is analyzed; second the interpolation algorithm model is setup based on the Hamming window; then the fast implementation of the algorithm using the Newton iteration method is given. Using the numerical simulation the feasibility of algorithm is validated. Finally, the electrical circuit experiment shows the practicality of the algorithm in the electrical engineering. 展开更多
关键词 nonstationary signal INTERPOLATION ANTI-ALIASING short time fourier transform (STFT) iterative algorithm.
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Fast Fourier single-pixel imaging based on Sierra–Lite dithering algorithm 被引量:4
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作者 Zhen-Yu Liang Zheng-Dong Cheng +2 位作者 Yan-Yan Liu Kuai-Kuai Yu Yang-Di Hu 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第6期189-194,共6页
The single-pixel imaging(SPI) technique is able to capture two-dimensional(2 D) images without conventional array sensors by using a photodiode. As a novel scheme, Fourier single-pixel imaging(FSI) has been proven cap... The single-pixel imaging(SPI) technique is able to capture two-dimensional(2 D) images without conventional array sensors by using a photodiode. As a novel scheme, Fourier single-pixel imaging(FSI) has been proven capable of reconstructing high-quality images. Due to the fact that the Fourier basis patterns(also known as grayscale sinusoidal patterns)cannot be well displayed on the digital micromirror device(DMD), a fast FSI system is proposed to solve this problem by binarizing Fourier pattern through a dithering algorithm. However, the traditional dithering algorithm leads to low quality as the extra noise is inevitably induced in the reconstructed images. In this paper, we report a better dithering algorithm to binarize Fourier pattern, which utilizes the Sierra–Lite kernel function by a serpentine scanning method. Numerical simulation and experiment demonstrate that the proposed algorithm is able to achieve higher quality under different sampling ratios. 展开更多
关键词 single-pixel IMAGING binary fourier basis pattern the dithering algorithm
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Adaptive split-step Fourier method for simulating ultrashort laser pulse propagation in photonic crystal fibres 被引量:3
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作者 李曙光 邢光龙 +5 位作者 周桂耀 韩颖 侯蓝田 胡明列 栗岩锋 王清月 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第2期437-443,共7页
In this paper, the generalized nonlinear Schrodinger equation (GNLSE) is solved by an adaptive split-step Fourier method (ASSFM). It is found that ASSFM must be used to solve GNLSE to ensure precision when the sol... In this paper, the generalized nonlinear Schrodinger equation (GNLSE) is solved by an adaptive split-step Fourier method (ASSFM). It is found that ASSFM must be used to solve GNLSE to ensure precision when the soliton selffrequency shift is remarkable and the photonic crystal fibre (PCF) parameters vary with the frequency considerably. The precision of numerical simulation by using ASSFM is higher than that by using split-step Fourier method in the process of laser pulse propagation in PCFs due to the fact that the variation of fibre parameters with the peak frequency in the pulse spectrum can be taken into account fully. 展开更多
关键词 photonic crystal fibre ultrashort laser pulse propagation adaptive split-step fourier method
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A Fourier Reconstruction Algorithm in π-Scheme Short-Scan SPECT 被引量:2
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作者 SHI Tingting WANG Jinping 《Wuhan University Journal of Natural Sciences》 CAS 2013年第2期97-101,共5页
In this paper, an approximate analytical algorithm in the form of direct Fourier reconstruction is obtained for the recon- struction of data functions arisen from ^-scheme short-scan sin- gle-photon emission computed ... In this paper, an approximate analytical algorithm in the form of direct Fourier reconstruction is obtained for the recon- struction of data functions arisen from ^-scheme short-scan sin- gle-photon emission computed tomography(SPECT) with uniform attenuation, and the modified central slice theorem is developed. Numerical simulations are conducted to demonstrate the effec- tiveness of the developed method. 展开更多
关键词 single-photon emission computed tomography(SPECT) inversion formula fourier reconstruction algorithm thecentral slice theorem n -scheme short-scan
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Fourier hologram method using Gerchberg-Saxton algorithm for parallel femtosecond laser processing
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作者 汪金礼 苏亚辉 +2 位作者 崔洪涛 杨亮 方志伟 《Journal of Measurement Science and Instrumentation》 CAS 2012年第3期304-306,共3页
In order to improve femtosecond laser throughput,a parallel processing system consisting of liquid crystal on silicon(LCOS)device as spatial light modulator is put forward.A method is described for displaying Fourier ... In order to improve femtosecond laser throughput,a parallel processing system consisting of liquid crystal on silicon(LCOS)device as spatial light modulator is put forward.A method is described for displaying Fourier hologram on LCOS,and a high uniformity of several diffraction peaks in the computer reconstruction is achieved.Application of this method to the parallel femtosecond laser processing is also demonstrated,and two intersecting rings and three tangent rings are fabricated respectively by one time in the photoresist. 展开更多
关键词 femtosecond laser parallel processing liquid crystal on silicon(LCOS) fourier hologram Gerchberg-Saxton(GS)algorithm
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Identification of Lubricating Oil Additives Using XGBoost and Ant Colony Optimization Algorithms 被引量:1
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作者 Xia Yanqiu Cui Jinwei +2 位作者 Xie Peiyuan Zou Shaode Feng Xin 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS CSCD 2024年第2期158-167,共10页
To address the problem of identifying multiple types of additives in lubricating oil,a method based on midinfrared spectral band selection using the eXtreme Gradient Boosting(XGBoost)algorithm combined with the ant co... To address the problem of identifying multiple types of additives in lubricating oil,a method based on midinfrared spectral band selection using the eXtreme Gradient Boosting(XGBoost)algorithm combined with the ant colony optimization(ACO)algorithm is proposed.The XGBoost algorithm was used to train and test three additives,T534(alkyl diphenylamine),T308(isooctyl acid thiophospholipid octadecylamine),and T306(trimethylphenol phosphate),separately,in order to screen for the optimal combination of spectral bands for each additive.The ACO algorithm was used to optimize the parameters of the XGBoost algorithm to improve the identification accuracy.During this process,the support vector machine(SVM)and hybrid bat algorithms(HBA)were included as a comparison,generating four models:ACO-XGBoost,ACO-SVM,HBA-XGboost,and HBA-SVM.The results showed that all four models could identify the three additives efficiently,with the ACO-XGBoost model achieving 100%recognition of all three additives.In addition,the generalizability of the ACO-XGBoost model was further demonstrated by predicting a lubricating oil containing the three additives prepared in our laboratory and a collected sample of commercial oil currently in use。 展开更多
关键词 lubricant oil additives fourier transform infrared spectroscopy type identification ACO-XGBoost combinatorial algorithm
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A Biproportional Construction Algorithm for Correctly Calculating Fourier Series of Aperiodic Non-Sinusoidal Signal
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作者 Zicheng Li Mingwei Ren +1 位作者 Zhaoling Chen Guohai Liu 《Engineering(科研)》 2021年第10期503-525,共23页
<span style="font-family:Verdana;">The </span><span style="font-family:Verdana;">Fourier series</span><span style="font-family:Verdana;"> (FS)</span>&l... <span style="font-family:Verdana;">The </span><span style="font-family:Verdana;">Fourier series</span><span style="font-family:Verdana;"> (FS)</span><span style="font-family:Verdana;"> applies to </span><span style="font-family:Verdana;">a </span><span style="font-family:Verdana;">periodic non-sinusoidal function</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">satisfying </span><span style="font-family:Verdana;">the </span><span style="font-family:Verdana;">Dirichlet conditions, whereas </span><span style="font-family:Verdana;">the</span><span style="font-family:Verdana;"> being-processed function</span><span style="font-family:;" "=""> <img src="Edit_5f802cf4-e7c1-43f0-9bf6-97cfac22ce08.png" alt="" style="white-space:normal;" /></span><span style="font-family:;" "=""></span><span style="font-family:;" "=""><span style="font-family:Verdana;"> in practical applications is usually an aperiodic non-sinusoidal signal. When </span><img src="Edit_5f802cf4-e7c1-43f0-9bf6-97cfac22ce08.png" alt="" /><span style="font-family:Verdana;"> is aperiodic, its calculated </span></span><span style="font-family:Verdana;">FS</span><span style="font-family:Verdana;"> is not correct, </span><span style="font-family:Verdana;">which is </span><span style="font-family:Verdana;">still a challenging problem. To overcome the problem, </span><span style="font-family:Verdana;">we</span><span style="font-family:Verdana;"> derive a direct calculation algorithm, a constant iterati</span><span style="font-family:Verdana;">on </span><span style="font-family:Verdana;">algorithm, and an optimal iterati</span><span style="font-family:Verdana;">on </span><span style="font-family:Verdana;">algorithm. The direct calculation algorithm correctly calculate</span><span style="font-family:Verdana;">s</span><span style="font-family:Verdana;"> its Fourier coefficients </span><span style="font-family:Verdana;">(FCs) </span><span style="font-family:;" "=""><span style="font-family:Verdana;">when </span><img src="Edit_5f802cf4-e7c1-43f0-9bf6-97cfac22ce08.png" alt="" style="white-space:normal;" /><span></span><span style="font-family:Verdana;"> is periodic</span></span><span style="font-family:Verdana;"> and </span><span style="font-family:Verdana;">satisf</span><span style="font-family:Verdana;">ies</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">the </span><span style="font-family:Verdana;">Dirichlet conditions</span><span style="font-family:Verdana;">.</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">B</span><span style="font-family:Verdana;">oth the constant iterati</span><span style="font-family:Verdana;">on</span><span style="font-family:Verdana;"> algorithm and the optimal</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">iterati</span><span style="font-family:Verdana;">on</span><span style="font-family:Verdana;"> algorithm provide </span><span style="font-family:Verdana;">an</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">idea</span><span style="font-family:;" "=""><span style="font-family:Verdana;"> of</span><span style="color:red;"> </span><span style="font-family:Verdana;">determining </span></span><span style="font-family:Verdana;">the </span><span style="font-family:;" "=""><span style="font-family:Verdana;">states of </span><img src="Edit_5f802cf4-e7c1-43f0-9bf6-97cfac22ce08.png" alt="" style="white-space:normal;" /><span></span></span><span style="font-family:Verdana;">.</span><span style="font-family:Verdana;"> From the </span><span style="font-family:Verdana;">idea</span><span style="font-family:Verdana;">, </span><span style="font-family:Verdana;">we obtain </span><span style="font-family:Verdana;">an algorithm for determining </span><span style="font-family:Verdana;">the </span><span style="font-family:;" "=""><span style="font-family:Verdana;">states of </span><img src="Edit_5f802cf4-e7c1-43f0-9bf6-97cfac22ce08.png" alt="" style="white-space:normal;" /><span></span><span style="font-family:Verdana;"> based on the optimal iterati</span></span><span style="font-family:Verdana;">on</span><span style="font-family:Verdana;"> algorithm. In the algorithm, </span><span style="font-family:Verdana;">the</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">variable</span><span style="font-family:Verdana;"> iterati</span><span style="font-family:Verdana;">on</span><span style="font-family:Verdana;"> step </span><span style="font-family:Verdana;">is</span><span style="font-family:Verdana;"> introduced</span><span style="font-family:Verdana;">;</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">t</span><span style="font-family:Verdana;">hus</span><span style="font-family:Verdana;">,</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">we present </span><span style="font-family:Verdana;">an algorithm for determining </span><span style="font-family:Verdana;">the </span><span style="font-family:;" "=""><span style="font-family:Verdana;">states of </span><img src="Edit_5f802cf4-e7c1-43f0-9bf6-97cfac22ce08.png" alt="" style="white-space:normal;" /><span></span><span style="font-family:Verdana;"> based on the </span></span><span style="font-family:Verdana;">variable</span><span style="font-family:Verdana;"> iterati</span><span style="font-family:Verdana;">on</span><span style="font-family:Verdana;"> step. </span><span style="font-family:Verdana;">The presented</span><span style="font-family:Verdana;"> algorithm accurately determine</span><span style="font-family:Verdana;">s</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">the </span><span style="font-family:;" "=""><span style="font-family:Verdana;">states of </span><img src="Edit_5f802cf4-e7c1-43f0-9bf6-97cfac22ce08.png" alt="" style="white-space:normal;" /><span></span></span><span style="font-family:Verdana;">. </span><span style="font-family:Verdana;">On the basis of the</span><span style="font-family:Verdana;">se</span><span style="font-family:Verdana;"> algorithms, </span><span style="font-family:Verdana;">we build </span><span style="font-family:Verdana;">a biproportional construction theory</span><span style="font-family:Verdana;">.</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">The </span><span style="font-family:Verdana;">theory</span><span style="font-family:Verdana;"> consists of a </span><span style="font-family:Verdana;">first </span><span style="font-family:Verdana;">and a second</span><span style="font-family:Verdana;"> proportional construction theory</span><span style="font-family:Verdana;">.</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">The</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">former</span><span style="font-family:Verdana;"> correctly </span><span style="font-family:Verdana;">calcula</span><span style="font-family:Verdana;">te</span><span style="font-family:Verdana;">s</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">the</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">FCs</span><span style="font-family:;" "=""><span style="font-family:Verdana;"> of </span><img src="Edit_5f802cf4-e7c1-43f0-9bf6-97cfac22ce08.png" alt="" style="white-space:normal;" /><span></span><span style="font-family:Verdana;"> at </span></span><span style="font-family:Verdana;">the present</span><span style="font-family:Verdana;"> samp</span><span style="font-family:Verdana;">ling time</span> 展开更多
关键词 fourier Coefficients (FCs) fourier Series (FS) Iteration algorithm Aperiodic Non-Sinusoidal Signal
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基于Fourier拟合的光伏跟踪系统设计 被引量:4
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作者 刘星宇 朱金荣 +1 位作者 盘瑶 张剑云 《南方能源建设》 2024年第1期54-63,共10页
[目的]为提高光伏支架的发电效率,以基于Fourier拟合算法的视日运动轨迹光伏跟踪器为研究设计对象。[方法]借助MATLAB分析了传统视日运动轨迹算法的跟踪精度情况,更进一步地在此基础上提出了精度更优的8阶傅里叶拟合视日运动轨迹跟踪算... [目的]为提高光伏支架的发电效率,以基于Fourier拟合算法的视日运动轨迹光伏跟踪器为研究设计对象。[方法]借助MATLAB分析了传统视日运动轨迹算法的跟踪精度情况,更进一步地在此基础上提出了精度更优的8阶傅里叶拟合视日运动轨迹跟踪算法,并结合GNSS定位技术,得出太阳实时运行轨迹。系统设计以STM32单片机作为微处理器,采用6轴加速度传感器,通过重力矢量在其轴上的投影确定光伏跟踪支架的实时倾斜度,以此二者建立跟踪支架三维运行模型,通过分析太阳光线在支架上的余弦效应即可得到电机需要运行的动作角。同时为解决晨昏时刻光伏组件间的阴影遮挡问题,系统增加逆跟踪算法。并考虑到大规模机组的应用,提出主从电机同步控制策略。[结果]傅-2里叶拟合算法拥有更高的跟踪精度,精度可达到10数量级,高于传统算法一个数量级。同时采用逆跟踪技术可节约24.3%光伏阵列用地面积,大幅提高了土地利用率。[结论]本研究采用更为精准的视日运动轨迹跟踪模型,较好地解决了太阳辐射利用的余弦效应,提升了电站的发电效率,实现了安全高效绿色能源体系的建设,促进了我国“双碳”目标的推进与达成。 展开更多
关键词 视日运动轨迹 光伏双轴 逆跟踪 fourier拟合算法 主从电机同步控制策略
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Calculation of Mass Concrete Temperature Containing Cooling Water Pipe Based on Substructure and Iteration Algorithm
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作者 Heng Zhang Chao Su +2 位作者 Zhizhong Song Zhenzhong Shen Huiguang Lei 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第1期813-826,共14页
Mathematical physics equations are often utilized to describe physical phenomena in various fields of science and engineering.One such equation is the Fourier equation,which is a commonly used and effective method for... Mathematical physics equations are often utilized to describe physical phenomena in various fields of science and engineering.One such equation is the Fourier equation,which is a commonly used and effective method for evaluating the effectiveness of temperature control measures for mass concrete.One important measure for temperature control in mass concrete is the use of cooling water pipes.However,the mismatch of grids between large-scale concrete models and small-scale cooling pipe models can result in a significant waste of calculation time when using the finite element method.Moreover,the temperature of the water in the cooling pipe needs to be iteratively calculated during the thermal transfer process.The substructure method can effectively solve this problem,and it has been validated by scholars.The Abaqus/Python secondary development technology provides engineers with enough flexibility to combine the substructure method with an iteration algorithm,which enables the creation of a parametric modeling calculation for cooling water pipes.This paper proposes such a method,which involves iterating the water pipe boundary and establishing the water pipe unit substructure to numerically simulate the concrete temperature field that contains a cooling water pipe.To verify the feasibility and accuracy of the proposed method,two classic numerical examples were analyzed.The results showed that this method has good applicability in cooling pipe calculations.When the value of the iteration parameterαis 0.4,the boundary temperature of the cooling water pipes can meet the accuracy requirements after 4∼5 iterations,effectively improving the computational efficiency.Overall,this approach provides a useful tool for engineers to analyze the temperature control measures accurately and efficiently for mass concrete,such as cooling water pipes,using Abaqus/Python secondary development. 展开更多
关键词 fourier equation cooling water pipe mass concrete iteration algorithm
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二阶Radon-Fourier变换与遗传算法结合的快速相参积累算法
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作者 范培毅 郭一帆 +2 位作者 景海涛 原浩娟 冀文辉 《电讯技术》 北大核心 2024年第11期1858-1865,共8页
针对匀加速运动的高速目标,可以用二阶Radon-Fourier变换(Second-order Radon-Fourier Transform,SRFT)完成对回波信号的相参积累。SRFT算法的原理是通过“速度-加速度”联合搜索来实现目标的运动参数估计,其计算量较大,不满足实时检测... 针对匀加速运动的高速目标,可以用二阶Radon-Fourier变换(Second-order Radon-Fourier Transform,SRFT)完成对回波信号的相参积累。SRFT算法的原理是通过“速度-加速度”联合搜索来实现目标的运动参数估计,其计算量较大,不满足实时检测的需求。针对这个问题,提出一种基于遗传算法(Genetic Algorithm,GA)的快速实现方法。首先对运动参数集进行编码,设置初始群体;然后通过遗传算法对群体更新迭代,使其能够自发快速地逼近全局最优解,减少不必要的搜索路径;最终快速实现待检测目标的相参积累。仿真结果表明,在保证检测性能的前提下,算法计算量得到有效改善,运算次数减少大约一个量级。 展开更多
关键词 目标检测 二阶Radon-fourier变换 相参积累 参数估计 遗传算法
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快速傅里叶算法在配网电能质量谐波智能监测中的应用 被引量:1
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作者 陈涛 刘超 蔡小鹏 《粘接》 2025年第3期142-145,共4页
新型配电网运行时,主要利用基于小波变换的频域方法进行谐波智能监测,忽略了电能信号的时域特征,导致监测结果存在很大的相对误差。因此,提出基于快速傅里叶算法的新型配电网电能质量谐波智能监测研究。运用以DSP芯片的谐波测试装置,采... 新型配电网运行时,主要利用基于小波变换的频域方法进行谐波智能监测,忽略了电能信号的时域特征,导致监测结果存在很大的相对误差。因此,提出基于快速傅里叶算法的新型配电网电能质量谐波智能监测研究。运用以DSP芯片的谐波测试装置,采集新型配电网电能质量谐波数据,并考虑A/D转换过程中存在的增益误差,对采集数据进行校正处理。依托于时域与频域相结合的思路,引入快速傅里叶算法和四谱线插值原理,对特征提取结果进一步检测,确定谐波信号的幅值和相位,得出电能质量谐波智能监测结果。结果表明:所提方法应用后得出的智能检测结果幅值、相位平均相对误差分别为10^(-6)%~10^(-8)%、10^(-8)%~10^(-10)%,且智能监测时间在10 ms以内。 展开更多
关键词 快速傅里叶算法 配电网 电能质量 谐波 数据特征 监测
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基于频域分析的热系统高效动态模拟算法
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作者 李航 滕润航 +1 位作者 赵甜 陈群 《工程热物理学报》 北大核心 2025年第1期217-225,共9页
换热器的高效、准确动态模拟是热系统性能动态分析的关键,然而基于时、空离散的有限差分/体积法难以兼顾模拟计算的精度与速度,不利于热系统的动态性能分析。本文提出一种频域热系统动态模拟高效算法,通过傅里叶变换导出系统内换热器的... 换热器的高效、准确动态模拟是热系统性能动态分析的关键,然而基于时、空离散的有限差分/体积法难以兼顾模拟计算的精度与速度,不利于热系统的动态性能分析。本文提出一种频域热系统动态模拟高效算法,通过傅里叶变换导出系统内换热器的频域控制方程,并将其分解为初始-扰动部分,分别解析和数值求解,叠加得到系统的动态响应。相比于有限差分法,本文所提出算法在保证精度(偏差<0.3 K)的同时可缩短计算时间约一个量级。 展开更多
关键词 换热器 频域分析 动态模拟 求解算法 傅里叶变换
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基于快速学习图卷积网络的滚动轴承故障诊断研究
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作者 宁少慧 董振才 +1 位作者 戎有志 周利东 《机床与液压》 北大核心 2025年第12期53-59,共7页
图神经网络跨层的递归邻域扩展为训练大型密集图带来时间方面的挑战,导致轴承故障诊断的训练效率不高。针对此问题,提出一种基于快速学习图卷积网络方法并将其应用于滚动轴承故障诊断中。利用快速傅里叶变换(FFT)将采集的轴承故障时域... 图神经网络跨层的递归邻域扩展为训练大型密集图带来时间方面的挑战,导致轴承故障诊断的训练效率不高。针对此问题,提出一种基于快速学习图卷积网络方法并将其应用于滚动轴承故障诊断中。利用快速傅里叶变换(FFT)将采集的轴承故障时域信号转化为频域数据,再利用K近邻(KNN)算法将频域信号转换为图数据,以图数据显示频域特征,极大丰富了输入信息;引入快速学习图卷积网络(Fast-GCN)模型,通过重要性采样对故障特征进行学习;最后,利用Log-Softmax函数输出最终分类结果,从而实现滚动轴承单一故障的分类。实验结果表明:所提模型在保证故障分类准确率的前提下,诊断速度显著提升,甚至比图卷积神经网络(GCN)的诊断速度增加了约1倍,且所提方法具有良好的半监督诊断性能与泛化能力。 展开更多
关键词 滚动轴承 故障诊断 K近邻(KNN)算法 快速傅里叶变换(FFT) 快速学习图卷积网络(Fast-GCN)
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一种基于频域内推理计算的长短期记忆神经网络硬件加速器设计
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作者 靳松 陈诗琪 《计算机学报》 北大核心 2025年第8期1781-1794,共14页
长短期记忆神经网络(Long Short-Term Memory,LSTM)可以捕捉到序列数据间长距离的依赖关系,因此在时间序列预测、自然语言分析和语音识别等领域得到广泛应用。然而,LSTM网络独特的门控机制和状态更新过程导致其推理计算的复杂度较高,参... 长短期记忆神经网络(Long Short-Term Memory,LSTM)可以捕捉到序列数据间长距离的依赖关系,因此在时间序列预测、自然语言分析和语音识别等领域得到广泛应用。然而,LSTM网络独特的门控机制和状态更新过程导致其推理计算的复杂度较高,参数量较大,对其在资源受限的边缘设备上的部署形成挑战。本文提出一种基于频域内推理计算的长短期记忆神经网络硬件加速器设计。采用循环分块矩阵对网络的权重参数进行压缩存储,结合快速傅里叶变换(Fast Fourier Transform,FFT)和频域激活函数实现频域内网络推理计算,避免在处理不同时间样本时频繁的时域-频域切换开销。采用坐标旋转数字计算机算法(Coordinate Rotation Digital Computer,CORDIC)替换频域内的乘法运算和超函数计算,实现LSTM的低功耗硬件部署。提出的硬件加速器在PYNQ-Z2开发板上进行了原型实现。面向开源时间序列数据集的实验结果表明,加速器实现了63.6μs的网络平均推理延迟,功耗1.743 W,相比时域LSTM推理计算延迟降低了44.2%,功耗降低6.4%。同时,BRAM和FIFO的资源占用率仅为5%和2%,相比时域LSTM推理计算分别降低了83%和91.2%。 展开更多
关键词 长短期记忆神经网络 分块循环矩阵 坐标旋转数字计算机 频域推理计算 快速傅里叶变换
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基于Fourier-Mellin算法的干涉图像配准 被引量:22
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作者 高莹莹 杨建峰 +1 位作者 马晓龙 陈浩锋 《光学精密工程》 EI CAS CSCD 北大核心 2007年第9期1415-1420,共6页
提出了采用Fourier-Mellin算法对大孔径静态干涉成像光谱仪的原始干涉图像进行配准的方法,用于校正由于推扫平台系统姿态不稳所造成的失真。采用Fourier-Mellin算法和相位相关算法求取干涉图像的旋转角度和缩放及平移参数,并通过多帧未... 提出了采用Fourier-Mellin算法对大孔径静态干涉成像光谱仪的原始干涉图像进行配准的方法,用于校正由于推扫平台系统姿态不稳所造成的失真。采用Fourier-Mellin算法和相位相关算法求取干涉图像的旋转角度和缩放及平移参数,并通过多帧未校正的图像和校正后的图像分别拼接成大面积地域图像来验证算法。实验结果表明,通过人眼判断,可以实现对图像的配准,配准精度达到1 pixel,基本满足将LASIS原始干涉图校正为不失真图像的要求。 展开更多
关键词 干涉图像 fourier-Mellin算法 图像配准
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复指数Fourier神经元网络隐神经元衍生算法 被引量:9
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作者 张雨浓 曾庆淡 +2 位作者 肖秀春 姜孝华 邹阿金 《计算机应用》 CSCD 北大核心 2008年第10期2503-2506,共4页
以平方可积空间上的复指数Fourier级数作为激励函数构造了新型Fourier神经元网络,并推导出采用加号逆表示的网络权值直接确定公式,克服了传统BP神经网络收敛速度慢、易陷于局部极小点、迭代学习易发生振荡等缺陷。并在此基础上构造了隐... 以平方可积空间上的复指数Fourier级数作为激励函数构造了新型Fourier神经元网络,并推导出采用加号逆表示的网络权值直接确定公式,克服了传统BP神经网络收敛速度慢、易陷于局部极小点、迭代学习易发生振荡等缺陷。并在此基础上构造了隐神经元衍生算法,克服了传统BP神经网络难以确定最优网络拓扑结构的缺点。理论分析及仿真实验表明,该复指数Fourier神经元网络能够一步计算网络最优权值且能自适应调整网络结构,对随机加性噪声具有抑制作用,并能高精度逼近非连续函数。 展开更多
关键词 fourier级数 前向神经网络 权值直接确定 衍生算法 复指数
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忆阻Fourier神经网络在图像复原中的应用 被引量:4
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作者 王丽丹 段书凯 段美涛 《西南大学学报(自然科学版)》 CAS CSCD 北大核心 2014年第1期1-6,共6页
将传统Fourier神经网络与忆阻器相结合,用忆阻器做突触,构建新型的忆阻Fourier神经网络.推导忆导变化与权值更新的关系,提出忆阻突触权值更新规则,构建单输入忆阻Fourier神经网络,提出忆阻BP算法对模糊二值图像和灰度进行处理.Matlab仿... 将传统Fourier神经网络与忆阻器相结合,用忆阻器做突触,构建新型的忆阻Fourier神经网络.推导忆导变化与权值更新的关系,提出忆阻突触权值更新规则,构建单输入忆阻Fourier神经网络,提出忆阻BP算法对模糊二值图像和灰度进行处理.Matlab仿真实验表明该算法可以有效实现图像复原,提高图像清晰度.忆阻Fourier神经网络有望用于解决复杂的图像处理问题. 展开更多
关键词 忆阻器 傅立叶神经网络 BP算法 图像复原
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