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Bi-extrapolated subgradient projection algorithm for solving multiple-sets split feasibility problem 被引量:3
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作者 DANG Ya-zheng GAO Yan 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2014年第3期283-294,共12页
This paper deals with a bi-extrapolated subgradient projection algorithm by intro- ducing two extrapolated factors in the iterative step to solve the multiple-sets split feasibility problem. The strategy is intend to ... This paper deals with a bi-extrapolated subgradient projection algorithm by intro- ducing two extrapolated factors in the iterative step to solve the multiple-sets split feasibility problem. The strategy is intend to improve the convergence. And its convergence is proved un- der some suitable conditions. Numerical results illustrate that the bi-extrapolated subgradient projection algorithm converges more quickly than the existing algorithms. 展开更多
关键词 Multiple-sets split feasibility problem SUBGRADIENT accelerated iterative algorithm convergence.
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Comparison of Cloud Type Classification with Split Window Algorithm Based on Different Infrared Band Combinations of Himawari-8 Satellite 被引量:1
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作者 Babag Purbantoro Jamrud Aminuddin +4 位作者 Naohiro Manago Koichi Toyoshima Nofel Lagrosas Josaphat Tetuko Sri Sumantyo Hiroaki Kuze 《Advances in Remote Sensing》 2018年第3期218-234,共17页
Cloud detection and classification form a basis in weather analysis. Split window algorithm (SWA) is one of the simple and matured algorithms used to detect and classify water and ice clouds in the atmosphere using sa... Cloud detection and classification form a basis in weather analysis. Split window algorithm (SWA) is one of the simple and matured algorithms used to detect and classify water and ice clouds in the atmosphere using satellite data. The recent availability of Himawari-8 data has considerably strengthened the possibility of better cloud classification owing to its enhanced multi-band configuration as well as high temporal resolution. In SWA, cloud classification is attained by considering the spatial distributions of the brightness temperature (BT) and brightness temperature difference (BTD) of thermal infrared bands. In this study, we compare unsupervised classification results of SWA using the band pair of band 13 and 15 (SWA13-15, 10 and 12 μm bands), versus that of band 15 and 16 (SWA15-16, 12 and 13 μm bands) over the Japan area. Different threshold values of BT and BTD are chosen in winter and summer seasons to categorize cloud regions into nine different types. The accuracy of classification is verified by using the cloud-top height information derived from the data of Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO). For this purpose, six different paths of the space-borne lidar are selected in both summer and winter seasons, on the condition that the time span of overpass falls within the time ranges between 01:00 and 05:00 UTC, which corresponds to the local time around noon. The result of verification indicates that the classification based on SWA13-15 can detect more cloud types as compared with that based on SWA15-16 in both summer and winter seasons, though the latter combination is useful for delineating cumulonimbus underneath dense cirrus 展开更多
关键词 CLOUD Type Detection Himawari-8 split WINDOW algorithm BRIGHTNESS Temperature
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Generation and Analysis of Hybrid-Electric Vehicle Transmission Shift Schedules with a Torque Split Algorithm 被引量:1
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作者 Nicholas J. Connelly Derek I. George +1 位作者 Andrew C. Nix W. Scott Wayne 《Journal of Transportation Technologies》 2020年第1期21-49,共29页
The increased concern over global climate change and lack of long-term sustainability of fossil fuels in the projected future has prompted further research into advanced alternative fuel vehicles to reduce vehicle emi... The increased concern over global climate change and lack of long-term sustainability of fossil fuels in the projected future has prompted further research into advanced alternative fuel vehicles to reduce vehicle emissions and fuel consumption. One of the primary advanced vehicle research areas involves electrification and hybridization of vehicles. As hybrid-electric vehicle technology has advanced, so has the need for more innovative control schemes for hybrid vehicles, including the development and optimization of hybrid powertrain transmission shift schedules. The hybrid shift schedule works in tandem with a cost function-based torque split algorithm that dynamically determines the optimal torque command for the electric motor and engine. The focus of this work is to develop and analyze the benefits and limitations of two different shift schedules for a position-3 (P3) parallel hybrid-electric vehicle. a traditional two-parameter shift schedule that operates as a function of vehicle accelerator position and vehicle speed (state of charge (SOC) independent shift schedule), and a three-parameter shift schedule that also adapts to fluctuations in the state of charge of the high voltage batteries (SOC dependent shift schedule). The shift schedules were generated using an exhaustive search coupled with a fitness function to evaluate all possible vehicle operating points. The generated shift schedules were then tested in the software-in-the-loop (SIL) environment and the vehicle-in-the-loop (VIL) environment and compared to each other, as well as to the stock 8L45 8-speed transmission shift schedule. The results show that both generated shift schedules improved upon the stock transmission shift schedule used in the hybrid powertrain comparing component efficiency, vehicle efficiency, engine fuel economy, and vehicle fuel economy. 展开更多
关键词 Hybrid-Electric Vehicles TORQUE split algorithm SHIFT SCHEDULE SHIFT Map COST Function SOC Dependent
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A single diffractive optical element implementing spectrum-splitting and beam-concentration functions simultaneously with high diffraction efficiency 被引量:2
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作者 叶佳声 王进泽 +3 位作者 黄庆礼 董碧珍 张岩 杨国桢 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第3期44-49,共6页
In this paper,a novel method is proposed and employed to design a single diffractive optical element(DOE) for implementing spectrum-splitting and beam-concentration(SSBC) functions simultaneously.We develop an opt... In this paper,a novel method is proposed and employed to design a single diffractive optical element(DOE) for implementing spectrum-splitting and beam-concentration(SSBC) functions simultaneously.We develop an optimization algorithm,through which the SSBC DOE can be optimized within an arbitrary thickness range according to the limitations of modern photolithography technology.Theoretical simulation results reveal that the designed SSBC DOE has a high optical focusing efficiency.It is expected that the designed SSBC DOE should have practical applications in high-efficiency solar cell systems. 展开更多
关键词 diffractive optical element spectrum-splitting and beam-concentration functions thickness optimization algorithm solar cell systems
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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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Self-Adaptive Algorithms for the Split Common Fixed Point Problem of the Demimetric Mappings
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作者 Xinhong Chen Yanlai Song +1 位作者 Jianying He Liping Gong 《Journal of Applied Mathematics and Physics》 2019年第10期2187-2199,共13页
The split common fixed point problem is an inverse problem that consists in finding an element in a fixed point set such that its image under a bounded linear operator belongs to another fixed-point set. In this paper... The split common fixed point problem is an inverse problem that consists in finding an element in a fixed point set such that its image under a bounded linear operator belongs to another fixed-point set. In this paper, we present new iterative algorithms for solving the split common fixed point problem of demimetric mappings in Hilbert spaces. Moreover, our algorithm does not need any prior information of the operator norm. Weak and strong convergence theorems are given under some mild assumptions. The results in this paper are the extension and improvement of the recent results in the literature. 展开更多
关键词 HILBERT Space Demimetric Mapping split Common Fixed Point PROBLEM SELF-ADAPTIVE algorithm
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On a New Analysis Framework for the Linear Convergence of Relaxed Operator Splitting Methods
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作者 Qingjing LI Ke GUO 《Journal of Mathematical Research with Applications》 CSCD 2022年第2期199-205,共7页
In this paper,we propose a new analysis framework to study the linear convergence of relaxed operator splitting methods,which can be viewed as an extension of the classic Krasnosel'skii-Mann iteration and Banach-P... In this paper,we propose a new analysis framework to study the linear convergence of relaxed operator splitting methods,which can be viewed as an extension of the classic Krasnosel'skii-Mann iteration and Banach-Picard contraction.As applications,we derive the linear convergence of the generalized proximal point algorithm and the relaxed forward-backward splitting method in a simple and elegant way. 展开更多
关键词 averaged operator negatively averaged operator relaxed forward-backward splitting method proximal point algorithm
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Splitting of Gaussian Models via Adapted BML Method Pertaining to Cry-Based Diagnostic System
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作者 Hesam Farsaie Alaie Chakib Tadj 《Engineering(科研)》 2013年第10期277-283,共7页
In this paper,we make use of the boosting method to introduce a new learning algorithm for Gaussian Mixture Models (GMMs) called adapted Boosted Mixture Learning (BML). The method possesses the ability to rectify the ... In this paper,we make use of the boosting method to introduce a new learning algorithm for Gaussian Mixture Models (GMMs) called adapted Boosted Mixture Learning (BML). The method possesses the ability to rectify the existing problems in other conventional techniques for estimating the GMM parameters, due in part to a new mixing-up strategy to increase the number of Gaussian components. The discriminative splitting idea is employed for Gaussian mixture densities followed by learning via the introduced method. Then, the GMM classifier was applied to distinguish between healthy infants and those that present a selected set of medical conditions. Each group includes both full-term and premature infants. Cry-pattern for each pathological condition is created by using the adapted BML method and 13-dimensional Mel-Frequency Cepstral Coefficients (MFCCs) feature vector. The test results demonstrate that the introduced method for training GMMs has a better performance than the traditional method based upon random splitting and EM-based re-estimation as a reference system in multi-pathological classification task. 展开更多
关键词 Adapted Boosted MIXTURE Learning GAUSSIAN MIXTURE Model splitting of GAUSSIANS Expected-Maximization algorithm CRY SIGNALS
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SPLIT-RADIX ALGORITHMS FOR LENGTH-p^m DHT
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作者 茅一民 《Journal of Electronics(China)》 1991年第2期97-103,共7页
The split-radix 2/4 algorithm for discrete Hartley transform(DHT)of length-2~m isnow very popular.In this paper,the split-radix approach is generalized to length-p^m DHT.It isshown that the radix-p/p^2 algorithm is su... The split-radix 2/4 algorithm for discrete Hartley transform(DHT)of length-2~m isnow very popular.In this paper,the split-radix approach is generalized to length-p^m DHT.It isshown that the radix-p/p^2 algorithm is superior to both the radix-p and the radix-p^2 algorithmsin the number of multiplications.As an example,a radix-3/9 fast algorithm for length-3~m DHTis developed.And its diagram of butterfly operation is given. 展开更多
关键词 ORTHOGONAL TRANSFORM Hartley TRANSFORM split-radix algorithm
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Variational Models for Color Image Inpainting and Their Split Bregman Algorithms
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作者 Jisheng Zhou Zhenkuan Pan Weibo Wei Guohao Liang 《科技信息》 2011年第6期153-156,共4页
Image inpainting is an important part of image science,but in the past,researches were focused on gray value image inpainting.In this paper,we investigate the inpainting effects of some variational models of color ima... Image inpainting is an important part of image science,but in the past,researches were focused on gray value image inpainting.In this paper,we investigate the inpainting effects of some variational models of color image diffusion.Five variational models for color image inpainting are proposed and their Split Bregman algorithms are designed.Their regularizers are LTV(Layered Total Variation) regularizer,CTV(Color Total Variation) regularizer,MTV(Multichannel Total Variation) regularizer,PA(Polyakov Action) regularizer and RPA(Reduced Polyakov Action) regularizer respectively.In order to compare their performances,we use the same data term...Some numerical experiments show the differences of the above mentioned models for color image inpainting. 展开更多
关键词 图像修复 色彩 图像处理 分层全变差
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一种改进的Split-Merge图像分割算法 被引量:4
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作者 谢钧 俞璐 吴乐南 《计算机应用》 CSCD 北大核心 2008年第7期1744-1746,共3页
图像分割的经典算法Split-Merge算法思路简洁、运算效率高,但存在边界定位不准确和过分割等问题。针对过分割问题提出了一种改进的Split-Merge算法,在合并过程中引入全局目标函数,并在目标函数中定义了长度项,使用贪心法完成合并过程。... 图像分割的经典算法Split-Merge算法思路简洁、运算效率高,但存在边界定位不准确和过分割等问题。针对过分割问题提出了一种改进的Split-Merge算法,在合并过程中引入全局目标函数,并在目标函数中定义了长度项,使用贪心法完成合并过程。长度项以及贪心法的使用促使相邻区域充分合并,有效地克服了过分割等问题,取得了较好的分割效果。 展开更多
关键词 图像分割 split—Merge算法 贪心法
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Split Bregman算法在遥感图像边缘检测中的应用研究 被引量:2
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作者 景雨 刘建鑫 +1 位作者 刘朝霞 李绍华 《计算机科学》 CSCD 北大核心 2017年第12期310-315,共6页
针对基于水平集的边缘检测方法抗噪性能差,处理模糊边界和灰度不均匀性的能力弱,计算效率低,边缘检测结果的精确性极大程度上依赖于初始轮廓的位置且曲线演化易陷入极小值等问题,提出一种基于全局最优凸函数变分模型和Split Bregman数... 针对基于水平集的边缘检测方法抗噪性能差,处理模糊边界和灰度不均匀性的能力弱,计算效率低,边缘检测结果的精确性极大程度上依赖于初始轮廓的位置且曲线演化易陷入极小值等问题,提出一种基于全局最优凸函数变分模型和Split Bregman数字最小化的边缘检测方法。该方法首先根据CV模型的构造原理,并利用Chan的全局最优化思想,构造了一个通用的可以获得全局最优解的凸函数变分模型;在曲线演化和数字最小化迭代过程中,引入了基于Split Bregman的快速迭代算法,可以使曲线在克服噪声等问题的影响下快速、准确、稳定地演化到目标的边界处。实验结果证明了提出的边缘检测方法既具有较高的计算效率,能够满足遥感图像边缘检测对实时性的要求,同时也具有较高的边缘检测精度和良好的普适性。 展开更多
关键词 边缘检测 主动轮廓模型 遥感图像 split Bregman算法
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New rank learning algorithm
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作者 刘华富 潘怡 王仲 《Journal of Southeast University(English Edition)》 EI CAS 2007年第3期447-450,共4页
To overcome the limitation that complex data types with noun attributes cannot be processed by rank learning algorithms, a new rank learning algorithm is designed. In the learning algorithm based on the decision tree,... To overcome the limitation that complex data types with noun attributes cannot be processed by rank learning algorithms, a new rank learning algorithm is designed. In the learning algorithm based on the decision tree, the splitting rule of the decision tree is revised with a new definition of rank impurity. A new rank learning algorithm, which can be intuitively explained, is obtained and its theoretical basis is provided. The experimental results show that in the aspect of average rank loss, the ranking tree algorithm outperforms perception ranking and ordinal regression algorithms and it also has a faster convergence speed. The rank learning algorithm based on the decision tree is able to process categorical data and select relative features. 展开更多
关键词 machine learning rank learning algorithm decision tree splitting rule
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基于Split Bregman算法的MRI图像重建参数分析 被引量:1
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作者 刘梅 廖柏林 《吉首大学学报(自然科学版)》 CAS 2015年第5期39-44,56,共7页
压缩感知理论已应用在MRI成像中,作为压缩感知的非线性重建算法的重要分支,以Split Bregman算法为代表的凸松弛法将信号重建问题转化为凸优化问题求解,其计算效率高.对Split Bregman算法的正则化参数功能和调节机制进行了理论研究,分析... 压缩感知理论已应用在MRI成像中,作为压缩感知的非线性重建算法的重要分支,以Split Bregman算法为代表的凸松弛法将信号重建问题转化为凸优化问题求解,其计算效率高.对Split Bregman算法的正则化参数功能和调节机制进行了理论研究,分析了正则化参数对该算法收敛精度和收敛速度的影响.仿真结果表明了3个正则化参数对MRI图像重建效率和精度的影响程度. 展开更多
关键词 压缩感知 磁共振图像重建 非线性求逆 凸松弛 split Bregman 算法
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基于Split-Bregman方法的稀疏角度CT重建算法研究 被引量:1
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作者 张丹丹 《商丘师范学院学报》 CAS 2016年第3期13-16,共4页
离散梯度变换已被广泛地用作稀疏算子,相应的全变差(TV)最小化方法也被用于基于压缩感知(CS)的CT重建中.与此同时Split-Bregman算法在求解L1正则化问题方面引起了很大关注,此方法对原来的L1正则化问题引入一个分裂变量后利用Bregman迭... 离散梯度变换已被广泛地用作稀疏算子,相应的全变差(TV)最小化方法也被用于基于压缩感知(CS)的CT重建中.与此同时Split-Bregman算法在求解L1正则化问题方面引起了很大关注,此方法对原来的L1正则化问题引入一个分裂变量后利用Bregman迭代求解.本文将Split-Bregman方法用于稀疏角度CT重建,并与传统的SART和基于SART的软阈值算法(STF-SART)进行比较,最后用Head模型作为测试模型进行仿真实验,实验结果表明:对于稀疏角度CT重建问题,TV正则化(STF-SART和Split-Bregman)算法明显优于传统的SART算法,且Split-Bregman算法在收敛速度和重建图像质量方面又优于STF-SART算法. 展开更多
关键词 离散梯度变化 压缩感知 稀疏角度CT TV最小化 split-Bregman算法
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在Split-Merge框架下进行基于图的图像分割
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作者 俞璐 吴乐南 谢钧 《数据采集与处理》 CSCD 北大核心 2009年第3期300-303,共4页
Split-Merge算法是图像分割领域的经典算法,思路简洁、运算效率高,但因分裂位置和形状固定,导致出现方块效应和边界定位不准确等问题。现有的各种改进算法不能从根本上解决这些问题,为此本文将基于图的分割算法纳入到Split-Merge框架中... Split-Merge算法是图像分割领域的经典算法,思路简洁、运算效率高,但因分裂位置和形状固定,导致出现方块效应和边界定位不准确等问题。现有的各种改进算法不能从根本上解决这些问题,为此本文将基于图的分割算法纳入到Split-Merge框架中来,提出了在Split-Merge框架下进行基于图的分割。新算法把传统的基于图割值的算法作为分裂阶段的处理手段,在合并阶段采用本文提出的一种与访问次序无关的合并算法。新算法既解决了Split-Merge算法中因分裂位置和形状固定而带来的各种问题,也有效地消除了在基于图的分割中常见的"过分割"现象,取得了满意的分割效果。 展开更多
关键词 图像分割 split—Merge算法 基于图的分割
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基于Split Bregman算法的图像处理 被引量:1
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作者 石国良 《中国传媒大学学报(自然科学版)》 2017年第2期32-37,共6页
在本文中,我们介绍了图像去噪的经典模型-TV去噪模型,TV去噪能更好地保留图像的边缘细节。我们通过实验使用Split Bregman迭代算法对TV模型进行图像去噪,最终我们得出Split Bregman算法收敛速度快,处理TV去噪模型时也能保留图像的细节。
关键词 图像去噪 TV模型 split Bregman迭代算法 保留图像细节
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基于非局部正则化的乘性噪声去除模型及Split-Bregman算法
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作者 高冉 程东旭 《中原工学院学报》 CAS 2016年第4期18-22,共5页
针对全变分去噪模型会模糊图像边缘和纹理部分的问题,提出一种改进的去除乘性噪声的非局部正则化模型,并利用Split-Bregman算法进行求解。对观测图像取对数变换,将乘性噪声转化为加性噪声,利用全变分思想,以非局部TV范数作为正则项,通... 针对全变分去噪模型会模糊图像边缘和纹理部分的问题,提出一种改进的去除乘性噪声的非局部正则化模型,并利用Split-Bregman算法进行求解。对观测图像取对数变换,将乘性噪声转化为加性噪声,利用全变分思想,以非局部TV范数作为正则项,通过图像区域与区域的灰度相似性来确定权重系数,进而更好地保持图像的纹理结构;在模型中加入紧凑项来保证去噪图像的紧凑性。对模型求解并进行数值仿真实验,结果表明:改进的去除乘性噪声的非局部正则化模型能够去除图像噪声且较好地保持其纹理部分。 展开更多
关键词 全变差 非局部正则化 乘性噪声 分裂算法
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基于Split-Bregman方法的CT内重建算法研究
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作者 张丹丹 张煜林 《商丘师范学院学报》 CAS 2016年第6期26-29,共4页
基于压缩感知(CS)理论,可证明只要感兴趣区域(ROI)可以表示为分段常数或多项式,CT内重建问题就可得到精确稳定的解.问题的关键是如何在截断投影数据的约束下最小化感兴趣区域的全变差(TV).与此同时,Split-Bregman方法在求解CT图像重建T... 基于压缩感知(CS)理论,可证明只要感兴趣区域(ROI)可以表示为分段常数或多项式,CT内重建问题就可得到精确稳定的解.问题的关键是如何在截断投影数据的约束下最小化感兴趣区域的全变差(TV).与此同时,Split-Bregman方法在求解CT图像重建TV最小化方面引起了很大关注.本文基于CS理论将Split-Bregman方法用于一个分段常数成像模型的ROI重建,并与传统的SART和基于SART的软阈值算法(STF-SART)进行比较.最后经Shepp-Logan模型数值模拟表明:该方法适用、有效. 展开更多
关键词 压缩感知 CT内重建 全变差最小化 split-Bregman算法 分段常数成像模型
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多相图像分割的交替凸松弛优化及其Split Bregman算法 被引量:1
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作者 王丽娅 潘振宽 +3 位作者 魏伟波 刘存良 张志梅 王钰 《山东大学学报(工学版)》 CAS 北大核心 2011年第2期40-45,共6页
变分水平集模型已成为多相图像分割的基本框架,其求解过程通常为计算水平集函数演化方程的稳态解,计算效率不高。为提高计算效率,本研究采用n个水平集函数划分n个区域的分段常值多相图像分割变分模型,将对水平集函数的优化问题转化为对... 变分水平集模型已成为多相图像分割的基本框架,其求解过程通常为计算水平集函数演化方程的稳态解,计算效率不高。为提高计算效率,本研究采用n个水平集函数划分n个区域的分段常值多相图像分割变分模型,将对水平集函数的优化问题转化为对离散的二值水平集函数的优化问题;然后将其转化为凸优化问题,再通过对结果阈值化得到原问题的解,并且本研究设计了相应的Split Bregman算法;最后通过多个平面图像分割实例说明了本文模型与传统模型相比在计算效率上的提升,并且通过三维多相图像分割实例验证了本文方法的有效性。 展开更多
关键词 多相图像分割 变分方法 凸优化方法 split Bregman算法
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