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A new algorithm of retrieving a petroleum substances absorption coefficient in sea water based on a remote sensing image 被引量:7
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作者 HUANG Miaofen XING Xufeng +2 位作者 SONG Qingjun LIU Yang DONG Wentong 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2016年第11期97-104,共8页
Establishing the remote sensing algorithm of retrieving the absorption coefficient of seawater petroleum substances is an efficient way to improve the accuracy of retrieving a seawater petroleum concentration using a ... Establishing the remote sensing algorithm of retrieving the absorption coefficient of seawater petroleum substances is an efficient way to improve the accuracy of retrieving a seawater petroleum concentration using a remote sensing technology. A remote sensing reflectance is a basic physical parameter in water color remote sensing. Apply it to directly retrieve the absorption coefficient of seawater petroleum substances is of potential advantage. The absorption coefficient of waters containing petroleum [ACWCP, a_o(λ)], consists of the absorption coefficient of pure water [ACPW, a_w(λ)], plankton [ACP, a_(ph)(λ)], colored scraps [ACCS, a_(d,g)(λ)], and petroleum substance [ACPS, a_(oil)(λ)]. Among those, ACCS consists of the absorption coefficient of nonalgal particle [ACNP, a_d(λ)] and colored dissolved organic matter [ACCDOM, a_g(λ)]. For waters containing petroleum, the retrieved ACCS using the existing method is a combination absorption coefficient of ACNP,ACCDOM and ACPA [CAC, a_(d,g,oil)(λ)]. Therefore, the principle question is how to extract ACPS from CAC.Through the analysis of the three proportion tests conducted between the year of 2013 and 2015 and the corresponding remote sensing data, an algorithm of retrieving the absorption coefficient of petroleum substances is proposed based on remote sensing reflectance. First of all, ACPS and CAC are retrieved from the reflectance using the quasi-analytical algorithm(QAA), with some parameter modified. Secondly, given the fact that the backscatter coefficient [BC, b_(bp)(555)] of total particles at 555 nm can be obtained completely from the reflectance, the relation between BC and ACNP in petroleum contaminated water can be established. As a result, ACNP can be calculated. Then, combining the remote sensing retrieving algorithm of a_g(440), the method of achieving the spectral slope of the absorption coefficient can be established, from which ACCDOM,can be calculated. Finally, ACPS can be computed as the residual. The accuracy of ACPS based on this algorithm is 86% compared with the in situ measurements. 展开更多
关键词 petroleum substances in sea water remote sensing technology absorption coefficient retrieval algorithm
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Up-Sampled Cross-Correlation Based Object Tracking & Vibration Measurement in Agriculture Tractor System
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作者 R.Ganesan G.Sankaranarayanan +1 位作者 M.Pradeep Kumar V.K.Bupesh Raja 《Intelligent Automation & Soft Computing》 SCIE 2023年第4期667-681,共15页
This research introduces a challenge in integrating and cleaning the data,which is a crucial task in object matching.While the object is detected and then measured,the vibration at different light intensities may influ... This research introduces a challenge in integrating and cleaning the data,which is a crucial task in object matching.While the object is detected and then measured,the vibration at different light intensities may influence the durability and reliability of mechanical systems or structures and cause problems such as damage,abnormal stopping,and disaster.Recent research failed to improve the accuracy rate and the computation time in tracking an object and in the vibration measurement.To solve all these problems,this proposed research simplifies the scaling factor determination by assigning a known real-world dimension to a predetermined portion of the image.A novel white color sticker of the known dimensions marked with a color dot is pasted on the surface of an object for the best result in the template matching using the Improved Up-Sampled Cross-Correlation(UCC)algorithm.The vibration measurement is calculated using the Finite-Difference Algorithm(FDA),a machine vision systemfitted with a macro lens sensor that is capable of capturing the image at a closer range,which does not affect the quality of displacement measurement from the video frames.Thefield test was conducted on the TAFE(Tractors and Farm Equipment Limited)tractor parts,and the percentage of error was recorded between 30%and 50%at very low vibration values close to zero,whereas it was recorded between 5%and 10%error in most high-accelerations,the essential range for vibration analysis.Finally,the suggested system is more suitable for measuring the vibration of stationary machinery having low frequency ranges.The use of a macro lens enables to capture of image frames at very close-ups.A 30%to 50%error percentage has been reported when the vibration amplitude is very small.Therefore,this study is not suitable for Nano vibration analysis. 展开更多
关键词 Vibration measurement object tracking up-sampled cross-correlation finite difference algorithm template matching macro lens machine vision
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Optimization of Submarine Hydrodynamic Coefficients Based on Immune Genetic Algorithm 被引量:1
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作者 胡坤 徐亦凡 《Defence Technology(防务技术)》 SCIE EI CAS 2010年第3期200-205,共6页
Aiming at the demand for optimization of hydrodynamic coefficients in submarine's motion equations,an adaptive weight immune genetic algorithm was proposed to optimize hydrodynamic coefficients in motion equations... Aiming at the demand for optimization of hydrodynamic coefficients in submarine's motion equations,an adaptive weight immune genetic algorithm was proposed to optimize hydrodynamic coefficients in motion equations.Some hydrodynamic coefficients of high sensitivity to control and maneuver were chosen as the optimization objects in the algorithm.By using adaptive weight method to determine the weight and target function,the multi-objective optimization could be translated into single-objective optimization.For a certain kind of submarine,three typical maneuvers were chosen to be the objects of study:overshoot maneuver in horizontal plane,overshoot maneuver in vertical plane and turning circle maneuver in horizontal plane.From the results of computer simulations using primal hydrodynamic coefficient and optimized hydrodynamic coefficient,the efficiency of proposed method is proved. 展开更多
关键词 fluid mechanics SUBMARINE hydrodynamic coefficient adaptive weight immune genetic algorithm OPTIMIZATION
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Terrain Rendering LOD Algorithm Based on Improved Restrictive Quadtree Segmentation and Variation Coefficient of Elevation 被引量:2
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作者 Zhenwu Wang Xiaohua Lu 《Journal of Beijing Institute of Technology》 EI CAS 2018年第4期617-622,共6页
Aiming to deal with the difficult issues of terrain data model simplification and crack disposal,the paper proposed an improved level of detail(LOD)terrain rendering algorithm,in which a variation coefficient of eleva... Aiming to deal with the difficult issues of terrain data model simplification and crack disposal,the paper proposed an improved level of detail(LOD)terrain rendering algorithm,in which a variation coefficient of elevation is introduced to express the undulation of topography.Then the coefficient is used to construct a node evaluation function in the terrain data model simplification step.Furthermore,an edge reduction strategy is combined with the improved restrictive quadtree segmentation to handle the crack problem.The experiment results demonstrated that the proposed method can reduce the amount of rendering triangles and enhance the rendering speed on the premise of ensuring the rendering effect compared with a traditional LOD algorithm. 展开更多
关键词 terrain data model simplification crack disposal level of detail(LOD)terrain rendering algorithm variation coefficient of elevation node evaluation function restrictive quadtree segmentation
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Estimation of Mutual Coupling Coefficient of the Array by Simulated Annealing Algorithm 被引量:1
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作者 GAO Huo-tao ZHENG Xia LI Yong-xu 《Wuhan University Journal of Natural Sciences》 CAS 2005年第6期1000-1004,共5页
We propose a method for estimating the mutual coupling coefficient among antennas in this paper which is based on the principle of signal subspace and the simulated annealing (SA) algorithm. The computer simulation ... We propose a method for estimating the mutual coupling coefficient among antennas in this paper which is based on the principle of signal subspace and the simulated annealing (SA) algorithm. The computer simulation has been conducted to illustrate the' excellent performance of this method and to demonstrate that it is statistically efficient. The benefit of this new method is that calibration signals and unknown signals can be received simultaneously, during the course of calibration. 展开更多
关键词 mutual coupling coefficient from array estimation of mutual coupling coefficient simulated annealing(SA) algorithm
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Method for electromagnetic detection satellites scheduling based on genetic algorithm with alterable penalty coefficient 被引量:1
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作者 Jun Li Hao Chen +2 位作者 Zhinong Zhong Ning Jing Jiangjiang Wu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2014年第5期822-832,共11页
The electromagnetic detection satellite (EDS) is a type of earth observation satellites (EOSs). The Information collected by EDSs plays an important role in some fields, such as industry, science and military. The... The electromagnetic detection satellite (EDS) is a type of earth observation satellites (EOSs). The Information collected by EDSs plays an important role in some fields, such as industry, science and military. The scheduling of EDSs is a complex combinatorial optimization problem. Current research mainly focuses on the scheduling of imaging satellites and SAR satellites, but little work has been done on the scheduling of EDSs for its specific characteristics. A multi-satellite scheduling model is established, in which the specific constrains of EDSs are considered, then a scheduling algorithm based on the genetic algorithm (GA) is proposed. To deal with the specific constrains of EDSs, a penalty function method is introduced. However, it is hard to determine the appropriate penalty coefficient in the penalty function. Therefore, an adaptive adjustment mechanism of the penalty coefficient is designed to solve the problem, as well as improve the scheduling results. Experimental results are used to demonstrate the correctness and practicability of the proposed scheduling algorithm. 展开更多
关键词 electromagnetic detection satellite (EDS) scheduling genetic algorithm (GA) constraint handling penalty function method alterable penalty coefficient.
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Coupled Cross-correlation Neural Network Algorithm for Principal Singular Triplet Extraction of a Cross-covariance Matrix 被引量:2
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作者 Xiaowei Feng Xiangyu Kong Hongguang Ma 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI 2016年第2期149-156,共8页
This paper proposes a novel coupled neural network learning algorithm to extract the principal singular triplet(PST)of a cross-correlation matrix between two high-dimensional data streams. We firstly introduce a novel... This paper proposes a novel coupled neural network learning algorithm to extract the principal singular triplet(PST)of a cross-correlation matrix between two high-dimensional data streams. We firstly introduce a novel information criterion(NIC),in which the stationary points are singular triplet of the crosscorrelation matrix. Then, based on Newton's method, we obtain a coupled system of ordinary differential equations(ODEs) from the NIC. The ODEs have the same equilibria as the gradient of NIC, however, only the first PST of the system is stable(which is also the desired solution), and all others are(unstable)saddle points. Based on the system, we finally obtain a fast and stable algorithm for PST extraction. The proposed algorithm can solve the speed-stability problem that plagues most noncoupled learning rules. Moreover, the proposed algorithm can also be used to extract multiple PSTs effectively by using sequential method. 展开更多
关键词 Singular value decomposition(SVD) coupled algorithm cross-correlation neural network(CNN) speed-stability problem principal singular subspace(PSS) principal singular triplet(PST)
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A research on statistical retrieval algorithms and spectral characteristics of the total absorption coefficients in the Yellow Sea and the East China Sea 被引量:4
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作者 王晓梅 唐军武 +2 位作者 宋庆君 丁静 马超飞 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2006年第3期236-242,共7页
This paper suggests a group of statistical algorithms for calculating the total absorption co- efficients based on in situ data of apparent optical property and inherent optical property collected with strict quality ... This paper suggests a group of statistical algorithms for calculating the total absorption co- efficients based on in situ data of apparent optical property and inherent optical property collected with strict quality assurance according to NASA ocean bio-optic protocols in the Yellow Sea and the East China Sea in spring 2003. The band-ratios of Rrs412/Rrs555, Rrs490/Rrs555 are used in the algorithms to derive the total absorption coefficients (at) at 412, 440, 488, 510, 532 and 555nm bands, respectively. The aver- age relative errors between inversed and measured values are less than 25.8%, with the correlative coeffi- cients (R2) being 0.75–0.85. Error sensitivity analysis shows that the maximum retrieval error is less than 24.0% at ±5% error in Rrs’s. So the statistical algorithms of this paper are practicable. In this paper, the relations between the total absorption coefficients at 412, 488, 510, 532, 555 nm and that of 440nm are also studied. The results show that the relations between the total absorption coefficients of 400–600 nm and that of 440 nm are correlated well and all of their correlative coefficients R2 are greater than 0.99. Furthermore, a regression analysis is also done for the slope of the linear relations and wavelengths, and the R2 is also 0.99. Thus it is possible to retrieve other bands’ total absorption coefficients with only one band absorption value, which significantly reduce the number of unknown parameters in studying other ocean color related problems. 展开更多
关键词 吸收系数 黄河 光谱 东海 沉积物
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Improving the Cellular Characteristics of Aluminum Foam for Maximum Sound Absorption Coefficient Using Genetic Algorithm
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作者 Mohammad Javad Jafari Mohsen Niknam Sharak +3 位作者 Ali Khavanin Touraj Ebadzadeh Mahmood Fazlali Rohollah Fallah Madvari 《Sound & Vibration》 EI 2021年第2期117-130,共14页
Fabricating of metal foams with desired morphological parameters including pore size,porosity and pore opening is possible now using sintering technology.Thus,if it is possible to determine the morphology of metal foa... Fabricating of metal foams with desired morphological parameters including pore size,porosity and pore opening is possible now using sintering technology.Thus,if it is possible to determine the morphology of metal foam to absorb sound at a given frequency,and then fabricate it through sintering,it is expected to have optimized metal foams for the best sound absorption.Theoretical sound absorption models such as Lu model describe the relationship between morphological parameters and the sound absorption coefficient.In this study,the Lu model was used to optimize the morphological parameters of aluminum metal foam for the best sound absorption coefficient.For this purpose,the Lu model was numerically solved using written codes in MATLAB software.After validating the proposed codes with benchmark data,the genetic algorithm(GA)was applied to optimize the affecting morphological parameters on the sound absorption coefficient.The optimization was carried out for the thicknesses of 5 mm to 40 mm at the sound frequency range of 250 Hz–8000 Hz.The optimized parameters ranged from 50%to 95%for porosity,0.1 mm to 4.5 mm for pore size,and 0.07 mm to 0.6 mm for pore opening size.The result of this study was applied to fabricate the desired aluminum metal foams for the best sound absorption.The novel approach applied in this study,is expected to be successfully applied in for best sound absorption in desired frequencies. 展开更多
关键词 Acoustic model Genetic algorithm(GA) metal foam optimization Sound Absorption coefficient(SAC)
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Algorithm and Design Methodology to Develop a PIFA with Optimized Reflection Coefficient for the ISM 868 MHz Band
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作者 Bouchta Hajjine Christophe Escriba +1 位作者 Daniel Medale Jean-Yves Fourniols 《Open Journal of Antennas and Propagation》 2016年第4期166-175,共10页
This paper presents a methodological approach to design a printed Inverted F antenna for the ISM 868 MHz band. For this design, the ground plane dimensions were kept fixed and the meandered radiating arm was modified ... This paper presents a methodological approach to design a printed Inverted F antenna for the ISM 868 MHz band. For this design, the ground plane dimensions were kept fixed and the meandered radiating arm was modified to obtain the best compromise integration/performances. This approach was then generalized to design meandered printed inverted F antennas. 展开更多
关键词 Design algorithm Meandered Antenna PIFA ISM Integration Reflection coefficient
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Calibration of Pipe Roughness Coefficient Based on Manning Formula and Genetic Algorithm
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作者 于志强 田一梅 +1 位作者 郑毅 赵新华 《Transactions of Tianjin University》 EI CAS 2009年第6期452-456,共5页
This paper presents a method to calibrate pipe roughness coefficient (i.e., Manning n-factor) with genetic algorithm (GA) under multiple loading conditions. Due to the old pipe age as well as deleting valves and blend... This paper presents a method to calibrate pipe roughness coefficient (i.e., Manning n-factor) with genetic algorithm (GA) under multiple loading conditions. Due to the old pipe age as well as deleting valves and blends in the skeleton of distribution network, most of the pipes in hydraulic model of practical water distribution system (WDS) are rough. The commonly used Hazen-Williams C-factor is therefore replaced by Manning n-factor in calibrating WDS hydraulic model. Adjustment to GA is designed, and the program efficiency is improved. A case study shows that the adjustment can save 60% of the total runtime. About 90% of the relative differences between simulated and observed pressures at monitoring locations are lower than 3%, which suggests that the proposed adjustment to the calibration is efficient and effective. 展开更多
关键词 遗传算法 曼宁公式 糙率系数 标定 粗糙系数 水工模型 旧管道 佐治亚州
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THEORETICAL MODEL OF EFFECTIVE STRESS COEFFICIENT FOR ROCK/SOIL-LIKE POROUS MATERIALS 被引量:5
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作者 Kai Zhang Hui Zhou Dawei Hu Yang Zhao Xiating Feng 《Acta Mechanica Solida Sinica》 SCIE EI 2009年第3期251-260,共10页
Physical mechanisms and influencing factors on the effective stress coefficient for rock/soil-like porous materials are investigated, based on which equivalent connectivity index is proposed. The equivalent connectivi... Physical mechanisms and influencing factors on the effective stress coefficient for rock/soil-like porous materials are investigated, based on which equivalent connectivity index is proposed. The equivalent connectivity index, relying on the meso-scale structure of porous material and the property of liquid, denotes the connectivity of pores in Representative Element Area (REA). If the conductivity of the porous material is anisotropic, the equivalent connectivity index is a second order tensor. Based on the basic theories of continuous mechanics and tensor analysis, relationship between area porosity and volumetric porosity of porous materials is deduced. Then a generalized expression, describing the relation between effective stress coefficient tensor and equivalent connectivity tensor of pores, is proposed, and the expression can be applied to isotropic media and also to anisotropic materials. Furthermore, evolution of porosity and equivalent connectivity index of the pore are studied in the strain space, and the method to determine the corresponding functions in expressions above is proposed using genetic algorithm and genetic programming. Two applications show that the results obtained by the method in this paper perfectly agree with the test data. This paper provides an important theoretical support to the coupled hydro-mechanical research. 展开更多
关键词 rock/soil-like porous materials generalized model for effective stress coefficient tensor equivalent connectivity index of pore genetic algorithm
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A Correlation Coefficient Approach for Evaluation of Stiffness Degradation of Beams Under Moving Load 被引量:1
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作者 Thanh Q.Nguyen Thao T.D.Nguyen +1 位作者 H.Nguyen-Xuan Nhi K.Ngo 《Computers, Materials & Continua》 SCIE EI 2019年第7期27-53,共27页
This paper presents a new approach using correlation and cross-correlation coefficients to evaluate the stiffness degradation of beams under moving load.The theoretical study of identifying defects by vibration method... This paper presents a new approach using correlation and cross-correlation coefficients to evaluate the stiffness degradation of beams under moving load.The theoretical study of identifying defects by vibration methods showed that the traditional methods derived from the vibration measurement data have not met the needs of the actual issues.We show that the correlation coefficients allow us to evaluate the degree and the effectiveness of the defects on beams.At the same time,the cross-correlation model is the basis for determining the relative position of defects.The results of this study are experimentally conducted to confirm the relationship between the correlation coefficients and the existence of the defects.In particular,the manuscript shows that the sensitivity of the correlation coefficients and cross-correlation is much higher than the parameters such as changes in stiffness(EJ)and natural frequency values(Δf).This study suggests using the above parameters to evaluate the stiffness degradation of beams by vibration measurement data in practice. 展开更多
关键词 Correlation coefficient cross-correlation vibration signal vibration amplitude FREQUENCY
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Effects of signal modulation and coloured cross-correlation of coloured noises on the diffusion of a harmonic oscillator
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作者 刘立 张良英 曹力 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第10期4182-4186,共5页
The diffusion in a harmonic oscillator driven by coloured noises ξ(t) and η(t) with coloured cross-correlation in which one of the noises is modulated by a biased periodic signal is investigated. The exact expre... The diffusion in a harmonic oscillator driven by coloured noises ξ(t) and η(t) with coloured cross-correlation in which one of the noises is modulated by a biased periodic signal is investigated. The exact expression of diffusion coefficient d as a function of noise parameter, signal parameter, and oscillator frequency is derived. The findings in this paper are as follows. 1) The curves of d versus noise intensity D and d versus noises cross-correlation time z3 exist as two different phases. The transition between the two phases arises from the change of the cross-correlation coefficient A of the two Ornstein-Uhlenbeck (O-U) noises. 2) Changing the value of T3, the curves of d versus Q, the intensity of colored noise that is modulated by the signal, can transform from a phase having a minimum to a monotonic phase. 3) Changing the value of signal amplitude A, d versus Q curves can transform from a phase having a minimum to a monotonic phase. The above-mentioned results demonstrate that a like noise-induced transition appears in the model. 展开更多
关键词 coloured cross-correlation cross-correlation coefficient diffusion coefficient signal modulated noise noise-induced transition
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Stochastic back analysis of permeability coefficient using generalized Bayesian method
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作者 Zheng Guilan Wang Yuan +1 位作者 Wang Fei Yang Jian 《Water Science and Engineering》 EI CAS 2008年第3期83-92,共10页
Owing to the fact that the conventional deterministic back analysis of the permeability coefficient cannot reflect the uncertainties of parameters, including the hydraulic head at the boundary, the permeability coeffi... Owing to the fact that the conventional deterministic back analysis of the permeability coefficient cannot reflect the uncertainties of parameters, including the hydraulic head at the boundary, the permeability coefficient and measured hydraulic head, a stochastic back analysis taking consideration of uncertainties of parameters was performed using the generalized Bayesian method. Based on the stochastic finite element method (SFEM) for a seepage field, the variable metric algorithm and the generalized Bayesian method, formulas for stochastic back analysis of the permeability coefficient were derived. A case study of seepage analysis of a sluice foundation was performed to illustrate the proposed method. The results indicate that, with the generalized Bayesian method that considers the uncertainties of measured hydraulic head, the permeability coefficient and the hydraulic head at the boundary, both the mean and standard deviation of the permeability coefficient can be obtained and the standard deviation is less than that obtained by the conventional Bayesian method. Therefore, the present method is valid and applicable. 展开更多
关键词 permeability coefficient stochastic back analysis generalized Bayesian method variable metric algorithm
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Parallel Processing Based on Ship Maneuvering in Identification of Interaction Force Coefficients 被引量:2
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作者 刘小健 黄国樑 邓德衡 《Journal of Shanghai Jiaotong university(Science)》 EI 2008年第3期352-356,共5页
The parallel processing based on the free running model test was adopted to predict the interac-tion force coefficients (flow straightening coefficient and wake fraction) of ship maneuvering. And the multi-population ... The parallel processing based on the free running model test was adopted to predict the interac-tion force coefficients (flow straightening coefficient and wake fraction) of ship maneuvering. And the multi-population genetic algorithm (MPGA) based on real coding that can contemporarily process the data of free running model and simulation of ship maneuvering was applied to solve the problem. Accordingly the optimal individual was obtained using the method of genetic algorithm. The parallel processing of multi-population solved the prematurity in the identification for single population, meanwhile, the parallel processing of the data of ship maneuvering (turning motion and zigzag motion) is an attempt to solve the coefficient drift problem. In order to validate the method, the interaction force coefficients were verified by the procedure and these coefficients measured were compared with those ones identified. The maximum error is less than 5%, and the identification is an effective method. 展开更多
关键词 船舶操纵 相互作用力系数 遗传算法 并行处理 参数辨识
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Remote sensing retrieval of total absorption coefficient in the Bohai Sea 被引量:1
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作者 青松 张杰 +1 位作者 崔廷伟 包玉海 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2012年第5期806-813,共8页
Temporal and spatial patterns of inherent optical properties in the Bohai Sea are very complex.In this paper,we used 77 groups of field data of AOPs(apparent optical properties) and IOPs(inherent optical properties) c... Temporal and spatial patterns of inherent optical properties in the Bohai Sea are very complex.In this paper,we used 77 groups of field data of AOPs(apparent optical properties) and IOPs(inherent optical properties) collected in June,August,and September of 2005 in the Bohai Sea,to retrieve the spectral total absorption coefficient a(λ) with the quasi-analytical algorithm(QAA).For QAA implementation,different bands in the region 680-730 nm(in 5 nm intervals) were selected and compared,to determine the optimal band domain of the reference wavelength.On this basis,we proposed a new algorithm(QAA-Com),a combination of QAA-685 and QAA-715,according to turbidity characterized by a(440).The percentage difference of model retrievals in the visible domain was between 4.5%-45.1%,in average of 18.8% for a(λ).The QAA model was then applied to Medium Resolution Imaging Spectrometer(MERIS) radiometric products,which were temporally and spatially matched with in-situ optical measurements.Differences between MERIS retrievals and in-situ values were in the range 9.2%-27.8% for a(λ) in the visible domain.Major errors in satellite retrieval are attributable to uncertainties of QAA model parameters and in-situ measurements,as well as imperfect atmospheric correction of MERIS data by the European Space Agency(ESA).During a storm surge in April 2009,time series of MERIS images together with the QAA model were used to analyze spatial and temporal variability of the total absorption coefficient pattern in the Bohai Sea.It is necessary to collect more independent field data to improve this algorithm. 展开更多
关键词 光谱吸收系数 遥感反演 渤海 中分辨率成像光谱仪 时间序列 光学特性 欧洲航天局 域模型
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Hybrid Global Optimization Algorithm for Feature Selection 被引量:1
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作者 Ahmad Taher Azar Zafar Iqbal Khan +1 位作者 Syed Umar Amin Khaled M.Fouad 《Computers, Materials & Continua》 SCIE EI 2023年第1期2021-2037,共17页
This paper proposes Parallelized Linear Time-Variant Acceleration Coefficients and Inertial Weight of Particle Swarm Optimization algorithm(PLTVACIW-PSO).Its designed has introduced the benefits of Parallel computing ... This paper proposes Parallelized Linear Time-Variant Acceleration Coefficients and Inertial Weight of Particle Swarm Optimization algorithm(PLTVACIW-PSO).Its designed has introduced the benefits of Parallel computing into the combined power of TVAC(Time-Variant Acceleration Coefficients)and IW(Inertial Weight).Proposed algorithm has been tested against linear,non-linear,traditional,andmultiswarmbased optimization algorithms.An experimental study is performed in two stages to assess the proposed PLTVACIW-PSO.Phase I uses 12 recognized Standard Benchmarks methods to evaluate the comparative performance of the proposed PLTVACIWPSO vs.IW based Particle Swarm Optimization(PSO)algorithms,TVAC based PSO algorithms,traditional PSO,Genetic algorithms(GA),Differential evolution(DE),and,finally,Flower Pollination(FP)algorithms.In phase II,the proposed PLTVACIW-PSO uses the same 12 known Benchmark functions to test its performance against the BAT(BA)and Multi-Swarm BAT algorithms.In phase III,the proposed PLTVACIW-PSO is employed to augment the feature selection problem formedical datasets.This experimental study shows that the planned PLTVACIW-PSO outpaces the performances of other comparable algorithms.Outcomes from the experiments shows that the PLTVACIW-PSO is capable of outlining a feature subset that is capable of enhancing the classification efficiency and gives the minimal subset of the core features. 展开更多
关键词 Particle swarm optimization(PSO) time-variant acceleration coefficients(TVAC) genetic algorithms differential evolution feature selection medical data
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Damage Identification in Beam-Type Structures Using Pseudo Strain Energy Density and Grey Relation Coefficient
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作者 陈晓强 朱宏平 +1 位作者 张俊兵 李林 《Transactions of Tianjin University》 EI CAS 2010年第2期96-103,共8页
Based on pseudo strain energy density (PSED) and grey relation coefficient (GRC), an index is proposed to locate the damage of beam-type structures in time-domain. The genetic algorithm (GA) is utilized to identify th... Based on pseudo strain energy density (PSED) and grey relation coefficient (GRC), an index is proposed to locate the damage of beam-type structures in time-domain. The genetic algorithm (GA) is utilized to identify the structural damage severity of confirmed damaged locations. Furthermore, a systematic damage identification program based on GA is developed on MATLAB platform. ANSYS is employed to conduct the finite element analysis of complicated civil engineering structures, which is embedded with interface technique. The two-step damage identification is verified by a finite element model of Xinxingtang Highway Bridge and a laboratory beam model based on polyvinylidens fluoride (PVDF). The bridge model was constructed with 57 girder segments, and simulated with 58 measurement points. The damaged segments were located accurately by GRC index regardless of damage extents and noise levels. With stiffness reduction factors of detected segments as variables, the GA program evolved for 150 generations in 6 h and identified the damage extent with the maximum errors of 1% and 3% corresponding to the noise to signal ratios of 0 and 5%, respectively. In contrast, the common GA-based method without using GRC index evolved for 600 generations in 24 h, but failed to obtain satisfactory results. In the laboratory test, PVDF patches were used as dynamic strain sensors, and the damage locations were identified due to the fact that GRC indexes of points near damaged elements were smaller than 0.6 while those of others were larger than 0.6. The GA-based damage quantification was also consistent with the value of crack depth in the beam model. 展开更多
关键词 灰色关联系数 能量密度 损伤识别 应变 结构
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基于特征融合和B-SVM的鸟鸣声识别算法 被引量:1
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作者 陈晓 曾昭优 《声学技术》 CSCD 北大核心 2024年第1期119-126,共8页
为了实现在野外通过低成本嵌入式系统识别鸟类,提出了基于特征融合和B-SVM的鸟鸣声识别方法。对鸟鸣声信号提取梅尔频率倒谱系数、翻转梅尔频率倒谱系数、短时能量和短时过零率组成特征参数,通过线性判别算法对特征参数进行特征融合。... 为了实现在野外通过低成本嵌入式系统识别鸟类,提出了基于特征融合和B-SVM的鸟鸣声识别方法。对鸟鸣声信号提取梅尔频率倒谱系数、翻转梅尔频率倒谱系数、短时能量和短时过零率组成特征参数,通过线性判别算法对特征参数进行特征融合。利用黑寡妇算法通过测试集对支持向量机模型的核参数和损失值进行优化得到B-SVM模型。利用Xeno-canto鸟鸣声数据集对本文算法进行了测试,结果表明该方法的识别准确率为93.23%。算法维度参数的大小和融合特征维度的高低是影响算法识别效果的重要因素。在相同条件下,文中所提的基于特征融合和B-SVM模型的鸟鸣声识别算法相较于其他特征参数和模型,识别的准确率更高,为野外鸟类识别提供了参考。 展开更多
关键词 鸟鸣声识别 梅尔频率倒谱系数 线性判别算法 黑寡妇优化算法 支持向量机
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