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New hybrid inertial CQ projection algorithms with line-search process for the split feasibility problem
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作者 DANG Ya-zheng WANG Long YANG Yao-heng 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2023年第1期144-158,共15页
In this paper, we propose two hybrid inertial CQ projection algorithms with linesearch process for the split feasibility problem. Based on the hybrid CQ projection algorithm, we firstly add the inertial term into the ... In this paper, we propose two hybrid inertial CQ projection algorithms with linesearch process for the split feasibility problem. Based on the hybrid CQ projection algorithm, we firstly add the inertial term into the iteration to accelerate the convergence of the algorithm, and adopt flexible rules for selecting the stepsize and the shrinking projection region, which makes an optimal stepsize available at each iteration. The shrinking projection region is the intersection of three sets, which are the set C and two hyperplanes. Furthermore, we modify the Armijo-type line-search step in the presented algorithm to get a new algorithm.The algorithms are shown to be convergent under certain mild assumptions. Besides, numerical examples are given to show that the proposed algorithms have better performance than the general CQ algorithm. 展开更多
关键词 split feasible problem INERTIAL Armijo-type line-search technique projection algorithm CONVERGENCE
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Low side lobe pattern synthesis using projection method with genetic algorithm for truncated cone conformal phased arrays 被引量:7
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作者 Guoqi Zeng Siyin Li +1 位作者 Yan Zhang Shanwei L 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2014年第4期554-559,共6页
A hybrid method for synthesizing antenna's three dimensional (3D) pattern is proposed to obtain the low sidelobe feature of truncated cone conformal phased arrays. In this method, the elements of truncated cone con... A hybrid method for synthesizing antenna's three dimensional (3D) pattern is proposed to obtain the low sidelobe feature of truncated cone conformal phased arrays. In this method, the elements of truncated cone conformal phased arrays are projected to the tangent plane in one generatrix of the truncated cone. Then two dimensional (2D) Chebyshev amplitude distribution optimization is respectively used in two mutual vertical directions of the tangent plane. According to the location of the elements, the excitation current amplitude distribution of each element on the conformal structure is derived reversely, then the excitation current amplitude is further optimized by using the genetic algorithm (GA). A truncated cone problem with 8x8 elements on it, and a 3D pattern desired side lobe level (SLL) up to 35 dB, is studied. By using the hybrid method, the optimal goal is accomplished with acceptable CPU time, which indicates that this hybrid method for the low sidelobe synthesis is feasible. 展开更多
关键词 conformal phased array low side lobe pattern synthe-sis projection method genetic algorithm optimization.
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Optimization of Multi-Execution Modes and Multi-Resource-Constrained Offshore Equipment Project Scheduling Based on a Hybrid Genetic Algorithm
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作者 Qi Zhou Jinghua Li +2 位作者 Ruipu Dong Qinghua Zhou Boxin Yang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第2期1263-1281,共19页
Offshore engineering construction projects are large and complex,having the characteristics of multiple execution modes andmultiple resource constraints.Their complex internal scheduling processes can be regarded as r... Offshore engineering construction projects are large and complex,having the characteristics of multiple execution modes andmultiple resource constraints.Their complex internal scheduling processes can be regarded as resourceconstrained project scheduling problems(RCPSPs).To solve RCPSP problems in offshore engineering construction more rapidly,a hybrid genetic algorithmwas established.To solve the defects of genetic algorithms,which easily fall into the local optimal solution,a local search operation was added to a genetic algorithm to defend the offspring after crossover/mutation.Then,an elitist strategy and adaptive operators were adopted to protect the generated optimal solutions,reduce the computation time and avoid premature convergence.A calibrated function method was used to cater to the roulette rules,and appropriate rules for encoding,decoding and crossover/mutation were designed.Finally,a simple network was designed and validated using the case study of a real offshore project.The performance of the genetic algorithmand a simulated annealing algorithmwas compared to validate the feasibility and effectiveness of the approach. 展开更多
关键词 Offshore project multi-execution modes resource-constrained project scheduling hybrid genetic algorithm
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Approximate subgradient projection algorithm for convex feasibility problem 被引量:1
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作者 Li Li Yan Gao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第3期527-530,共4页
An ε-subgradient projection algorithm for solving a convex feasibility problem is presented.Based on the iterative projection methods and the notion of ε-subgradient,a series of special projection hyperplanes is est... An ε-subgradient projection algorithm for solving a convex feasibility problem is presented.Based on the iterative projection methods and the notion of ε-subgradient,a series of special projection hyperplanes is established.Moreover,compared with the existing projection hyperplanes methods with subgradient,the proposed hyperplanes are interactive with ε,and their ranges are more larger.The convergence of the proposed algorithm is given under some mild conditions,and the validity of the algorithm is proved by the numerical test. 展开更多
关键词 ε-subgradient projection algorithm convex feasibility problem.
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The continuous wavelet projections algorithm: A practical spectral-feature-mining approach for crop detection 被引量:1
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作者 Xiaohu Zhao Jingcheng Zhang +3 位作者 Ruiliang Pu Zaifa Shu Weizhong He Kaihua Wu 《The Crop Journal》 SCIE CSCD 2022年第5期1264-1273,共10页
Spectroscopy can be used for detecting crop characteristics. A goal of crop spectrum analysis is to extract effective features from spectral data for establishing a detection model. An ideal spectral feature set shoul... Spectroscopy can be used for detecting crop characteristics. A goal of crop spectrum analysis is to extract effective features from spectral data for establishing a detection model. An ideal spectral feature set should have high sensitivity to target parameters but low information redundancy among features.However, feature-selection methods that satisfy both requirements are lacking. To address this issue,in this study, a novel method, the continuous wavelet projections algorithm(CWPA), was developed,which has advantages of both continuous wavelet analysis(CWA) and the successive projections algorithm(SPA) for generating optimal spectral feature set for crop detection. Three datasets collected for crop stress detection and retrieval of biochemical properties were used to validate the CWPA under both classification and regression scenarios. The CWPA generated a feature set with fewer features yet achieving accuracy comparable to or even higher than those of CWA and SPA. With only two to three features identified by CWPA, an overall accuracy of 98% in classifying tea plant stresses was achieved, and high coefficients of determination were obtained in retrieving corn leaf chlorophyll content(R^(2)= 0.8521)and equivalent water thickness(R^(2)= 0.9508). The mechanism of the CWPA ensures that the novel algorithm discovers the most sensitive features while retaining complementarity among features. Its ability to reduce the data dimension suggests its potential for crop monitoring and phenotyping with hyperspectral data. 展开更多
关键词 HYPERSPECTRAL Crop parameters Crop phenotyping Continuous wavelet analysis Successive projections algorithm
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Application of Projection Pursuit Evaluation Model Based on Real-Coded Accelerating Genetic Algorithm in Evaluating Wetland Soil Quality Variations in the Sanjiang Plain, China 被引量:34
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作者 FUQIANG XIEYONGGANG WEIZIMIN 《Pedosphere》 SCIE CAS CSCD 2003年第3期249-256,共8页
A new technique of dimension reduction named projection pursuit is applied to model and evaluatewetland soil quality variations in the Sanjiang Plain, Helongjiang Province, China. By adopting the im-proved real-coded ... A new technique of dimension reduction named projection pursuit is applied to model and evaluatewetland soil quality variations in the Sanjiang Plain, Helongjiang Province, China. By adopting the im-proved real-coded accelerating genetic algorithm (RAGA), the projection direction is optimized and multi-dimensional indexes are converted into low-dimensional space. Classification of wetland soils and evaluationof wetland soil quality variations are realized by pursuing optimum projection direction and projection func-tion value. Therefore, by adopting this new method, any possible human interference can be avoided andsound results can be achieved in researching quality changes and classification of wetland soils. 展开更多
关键词 改进遗传算法 沼泽土 土壤改良 土质评价 三江平原 投影追踪评价模型
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An algorithm for computed tomography image reconstruction from limited-view projections 被引量:5
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作者 王林元 李磊 +3 位作者 闫镔 江成顺 王浩宇 包尚联 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第8期642-647,共6页
With the development of the compressive sensing theory, the image reconstruction from the projections viewed in limited angles is one of the hot problems in the research of computed tomography technology. This paper d... With the development of the compressive sensing theory, the image reconstruction from the projections viewed in limited angles is one of the hot problems in the research of computed tomography technology. This paper develops an iterative algorithm for image reconstruction, which can fit the most cases. This method gives an image reconstruction flow with the difference image vector, which is based on the concept that the difference image vector between the reconstructed and the reference image is sparse enough. Then the l1-norm minimization method is used to reconstruct the difference vector to recover the image for flat subjects in limited angles. The algorithm has been tested with a thin planar phantom and a real object in limited-view projection data. Moreover, all the studies showed the satisfactory results in accuracy at a rather high reconstruction speed. 展开更多
关键词 limited-view problem computed tomography image reconstruction algorithms reconstruction-reference difference algorithm adaptive steepest descent-projection onto convex sets algorithm
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Hybrid alternate projection algorithm and its application for practical conformal array pattern synthesis
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作者 Fei Zhao Shunlian Chai +2 位作者 Huiying Qi Ke Xiao Junjie Mao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2012年第5期625-632,共8页
Based on the fabricated 12-element cavity-backed microstrip sector cylinder array,a novel hybrid alternate projection algorithm(HAPA),which combines analytical method with numerical techniques effectively,is propose... Based on the fabricated 12-element cavity-backed microstrip sector cylinder array,a novel hybrid alternate projection algorithm(HAPA),which combines analytical method with numerical techniques effectively,is proposed for synthesizing the pattern of practical conformal array.The algorithm applies the variable direction aperture projection method with mutual coupling correction techniques to provide the good initial excitations of elements to the enhanced alternate projection algorithm(EAPA).In order to do further optimization,which improves the convergent speed of the algorithm significantly.Finally,the HAPA has been applied to the fabricated sector cylinder array with mutual coupling considered.The results of synthesized patterns,such as low sidelobe with null points formed pattern,beam scanning with low sidelobe pattern and the shaped beam pattern are presented.It demonstrates the validity of HAPA in practical conformal array synthesis. 展开更多
关键词 conformal array alternate projection algorithm aperture projection method pattern synthesis mutual coupling
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Research and Implementation for License Plate Recognition Based on Improved Projection Algorithm 被引量:1
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作者 LI Xiu-juan Yimamu' aishan.Abudoulikemu 《Computer Aided Drafting,Design and Manufacturing》 2013年第2期53-56,75,共5页
This paper analyzes and dissertates the discrete wavelet transform and improved projection algorithm in four kernel stages (image preprocessing, license plate localization, character segmentation, license plate recog... This paper analyzes and dissertates the discrete wavelet transform and improved projection algorithm in four kernel stages (image preprocessing, license plate localization, character segmentation, license plate recognition, i.e.) of license plate recognition system in detail. At last, it gives some conclusions and suggestions on future research. 展开更多
关键词 license plate recognition wavelet transform improved projection algorithm
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Comparison of Microwave Imaging Algorithms for Short-Range Scenarios
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作者 Zhengyue Dong Ning Xu Kuiwen Xu 《Journal of Beijing Institute of Technology》 EI CAS 2024年第3期227-236,共10页
Three dimensional(3-D)imaging algorithms with irregular planar multiple-input-multiple-output(MIMO)arrays are discussed and compared with each other.Based on the same MIMO array,a modified back projection algorithm(MB... Three dimensional(3-D)imaging algorithms with irregular planar multiple-input-multiple-output(MIMO)arrays are discussed and compared with each other.Based on the same MIMO array,a modified back projection algorithm(MBPA)is accordingly proposed and four imaging algorithms are used for comparison,back-projection method(BP),back-projection one in time domain(BP-TD),modified back-projection one and fast Fourier transform(FFT)-based MIMO range migration algorithm(FFT-based MIMO RMA).All of the algorithms have been implemented in practical application scenarios by use of the proposed imaging system.Back to the practical applications,MIMO array-based imaging system with wide-bandwidth properties provides an efficient tool to detect objects hidden behind a wall.An MIMO imaging radar system,composed of a vector network analyzer(VNA),a set of switches,and an array of Vivaldi antennas,have been designed,fabricated,and tested.Then,these algorithms have been applied to measured data collected in different scenarios constituted by five metallic spheres in the absence and in the presence of a wall between the antennas and the targets in simulation and pliers in free space for experimental test.Finally,the focusing properties and time consumption of the above algorithms are compared. 展开更多
关键词 multiple-input-multiple-output(MIMO) short-range imaging back projection modi-fied back propagation range migration algorithm(RMA) through-wall imaging
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Novel method for extraction of ship target with overlaps in SAR image via EM algorithm
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作者 CAO Rui WANG Yong 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第4期874-887,共14页
The quality of synthetic aperture radar(SAR)image degrades in the case of multiple imaging projection planes(IPPs)and multiple overlapping ship targets,and then the performance of target classification and recognition... The quality of synthetic aperture radar(SAR)image degrades in the case of multiple imaging projection planes(IPPs)and multiple overlapping ship targets,and then the performance of target classification and recognition can be influenced.For addressing this issue,a method for extracting ship targets with overlaps via the expectation maximization(EM)algorithm is pro-posed.First,the scatterers of ship targets are obtained via the target detection technique.Then,the EM algorithm is applied to extract the scatterers of a single ship target with a single IPP.Afterwards,a novel image amplitude estimation approach is pro-posed,with which the radar image of a single target with a sin-gle IPP can be generated.The proposed method can accom-plish IPP selection and targets separation in the image domain,which can improve the image quality and reserve the target information most possibly.Results of simulated and real mea-sured data demonstrate the effectiveness of the proposed method. 展开更多
关键词 expectation maximization(EM)algorithm image processing imaging projection plane(IPP) overlapping ship tar-get synthetic aperture radar(SAR)
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A PROJECTION-TYPE ALGORITHM FOR SOLVING GENERALIZED MIXED VARIATIONAL INEQUALITIES 被引量:2
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作者 涂凯 夏福全 《Acta Mathematica Scientia》 SCIE CSCD 2016年第6期1619-1630,共12页
We propose a projection-type algorithm for generalized mixed variational in- equality problem in Euclidean space Rn. We establish the convergence theorem for the pro- posed algorithm, provided the multi-valued mapping... We propose a projection-type algorithm for generalized mixed variational in- equality problem in Euclidean space Rn. We establish the convergence theorem for the pro- posed algorithm, provided the multi-valued mapping is continuous and f-pseudomonotone with nonempty compact convex values on dom(f), where f : Rn --RU{+∞} is a proper func- tion. The algorithm presented in this paper generalize and improve some known algorithms in literatures. Preliminary computational experience is also reported. 展开更多
关键词 projection-type algorithm generalized mixed variational inequality f-pseudo-monotone mapping
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The application of projection pursuit classification in the process of strategy selection and evaluation based on the real coded accelerating genetic algorithm 被引量:1
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作者 JIANG Fa-zhu YANG Xiu-feng 《Chinese Business Review》 2008年第1期40-44,64,共6页
关键词 投影追踪 战略评估 遗传算法 中国 经济发展
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BEAM BROADENING SYNTHESIS FOR SAR ANTENNA ARRAY BASED ON PROJECTION MATRIX ALGORITHM
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作者 Jiao Junjun Sun Huifeng 《Journal of Electronics(China)》 2014年第5期433-440,共8页
A new beam broadening synthesis technique for Synthetic Aperture Radar(SAR) antenna array, namely Projection Matrix Algorithm(PMA) is presented. The theory of PMA is introduced firstly, and then the iterative renewed ... A new beam broadening synthesis technique for Synthetic Aperture Radar(SAR) antenna array, namely Projection Matrix Algorithm(PMA) is presented. The theory of PMA is introduced firstly, and then the iterative renewed manner is improved to resolve the unbalance problem under amplitude and phase control. In order to validate the algorithm correct and effective, an actual engineering application example is investigated. The beam synthesis results of 1.0~4.5 times broadening under the phase only control and the amplitude and phase control using improved PMA are given. The results show that the beam directivity, the beam broadening, and the side-lobe level requirements were met. It is demonstrated that the improved PMA was effective and feasible for SAR application. 展开更多
关键词 Synthetic Aperture Radar(SAR) antenna array Beam broadening synthesis projection Matrix algorithm(PMA) Phase only control Amplitude and phase control
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New Methodology for Direct Algorithms in Russell Projection "Stereographic Projection"
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作者 Mohammed Sabri Akresh 《Journal of Earth Science and Engineering》 2012年第4期253-256,共4页
关键词 直接算法 立体投影 罗素 偏微分方程 坐标测量 使用系统 测量工作 统计分析
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A GEOMETRIC ALGORITHM FOR TILTED-CAMERA PERSPECTIVE PROJECTION AND THE COMPARISON WITH EXTERNAL PERSPECTIVE PROJECTION
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作者 SHI Xiaoyan HU Yuju LU Xiangdong 《Geo-Spatial Information Science》 1998年第1期79-84,共6页
A geometric algorithm for Tilted-Camera Perspective(TCP)projec-tion is proposed in this paper based on the principle of perspective projection.Ac-cording to that,the difference between TCP projection and External Pe... A geometric algorithm for Tilted-Camera Perspective(TCP)projec-tion is proposed in this paper based on the principle of perspective projection.Ac-cording to that,the difference between TCP projection and External Perspective(EXP)projection is analyzed.It is put forward prerequisites making these twoprojections were compatible,and some examples are given. 展开更多
关键词 space PERSPECTIVE projection TCP projection EXP projection gemoetric algorithm compatible CONDITION
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求解粒子群粒度分布的改进Projection算法 被引量:2
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作者 葛宝臻 马云峰 魏耀林 《光学精密工程》 EI CAS CSCD 北大核心 2012年第1期197-203,共7页
针对在激光粒度分布反演中由于迭代算法的迭代步长选取不当致使反演结果存在严重展宽和拖尾的问题,提出一种调整迭代步长的方法应用于Projection算法来提高测量精度。该方法首先基于测距相似度原理得到光能分布列向量与光能系数矩阵行... 针对在激光粒度分布反演中由于迭代算法的迭代步长选取不当致使反演结果存在严重展宽和拖尾的问题,提出一种调整迭代步长的方法应用于Projection算法来提高测量精度。该方法首先基于测距相似度原理得到光能分布列向量与光能系数矩阵行向量之间的相似度曲线,经滤波和归一化处理后得到被测粒子群的预测粒度分布;然后根据预测粒度分布结果确定迭代步长的大小。使用本文提出的改进Projection算法测量国家标准物质GWB(E)120046的D50误差为-0.6%、D10误差为-1.1%、D90误差为-0.6%,测量GWB(E)120041与GWB(E)120049混合标准物质的光能对数误差为2.167。测量结果表明,该算法可有效地提高算法的抗噪声能力、测量精度和分辨率。 展开更多
关键词 激光粒度仪 粒度分布测量 projection算法 迭代步长
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Projection算法在粒子尺寸测量中的实验研究 被引量:3
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作者 王建萍 张以谟 李贺桥 《天津大学学报(自然科学与工程技术版)》 CSCD 2000年第4期460-463,共4页
提出了 projection迭代算法在激光粒度测量中的算法停止迭代条件 ,提高了 Projec-tion算法在实际粒子尺寸测量中的适用性 .通过对国家标准物质研究中心提供的微粒标准物质及其混合液的实际测试实验 ,证实了
关键词 激光粒度测量 迭代算法 粒子尺寸 实验
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Projection算法在光谱法检测上皮组织发育异常中的应用
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作者 王清华 李振华 +1 位作者 来建成 贺安之 《光电工程》 EI CAS CSCD 北大核心 2008年第2期21-24,共4页
由散射光谱推知上皮组织发育异常属于一类反问题,此问题可转化为反演上皮组织细胞核的粒径变化。对上皮组织细胞核的单次散射偏振光谱进行数值模拟,并采用Projection迭代算法反演细胞核的粒径分布信息。Projection迭代算法将方程组的解... 由散射光谱推知上皮组织发育异常属于一类反问题,此问题可转化为反演上皮组织细胞核的粒径变化。对上皮组织细胞核的单次散射偏振光谱进行数值模拟,并采用Projection迭代算法反演细胞核的粒径分布信息。Projection迭代算法将方程组的解看成是多维空间的一个点,通过不断求解各超平面上的投影点而逼近真值。数值计算表明,Projection算法对于粒径呈单峰、双峰分布细胞核均有良好的反演精度,采用该法有望增加光谱法上皮组织发育异常诊断的灵敏度。 展开更多
关键词 projection算法 散射光谱 反问题 上皮组织
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基于Projection算法的激光粒度测试反演算法研究
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作者 王雪艳 刘缠牢 《应用光学》 CAS CSCD 北大核心 2011年第2期367-372,共6页
针对Projection迭代反演算法对噪声极其敏感,及在实际应用中造成粒度测量失真的问题,引入Vondrak数据平滑算法对Projection反演进行平滑处理。借助Visual C++6.0开发平台,编写测试软件对算法应用进行了仿真研究。通过分析比较平滑处理... 针对Projection迭代反演算法对噪声极其敏感,及在实际应用中造成粒度测量失真的问题,引入Vondrak数据平滑算法对Projection反演进行平滑处理。借助Visual C++6.0开发平台,编写测试软件对算法应用进行了仿真研究。通过分析比较平滑处理前后的反演结果,得出Vondrak数据平滑处理算法的引入有效提高了Projection反演的抗干扰性能。实验结果表明:基于Vondrak数据平滑处理的Projection反演结果能够反映粒度的真实分布,满足现代粉体工业粒度测量的稳定可靠、精度高、抗干扰能力强的要求。 展开更多
关键词 粒度反演算法 projection迭代反演算法 光能误差 Vondrak平滑
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