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基于图像信息算法的2024年新疆乌什M_(S)7.1地震回溯性预测研究
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作者 袁伏全 黄浩 +2 位作者 徐玮阳 张晓清 刘兴盛 《地震研究》 北大核心 2026年第2期198-206,共9页
使用1970年以来新疆天山地震带及邻区的地震目录资料,基于图像信息(PI)算法,计算得到2016—2028年该地区逐年滑动的预测窗PI热点分布图像,并使用工作特征图表法(ROC)和R值评分法对PI算法的预测效能进行了检验。结果表明:①在2020—2024... 使用1970年以来新疆天山地震带及邻区的地震目录资料,基于图像信息(PI)算法,计算得到2016—2028年该地区逐年滑动的预测窗PI热点分布图像,并使用工作特征图表法(ROC)和R值评分法对PI算法的预测效能进行了检验。结果表明:①在2020—2024年回溯性预测图像中,2024年新疆乌什M_(S)7.1地震震中区域存在PI热点,具有较强的发震地点指示意义。②在5个回溯性预测时间窗(2016—2020年、2017—2021年、2018—2022年、2019—2023年、2020—2024年)内的PI热点图像演化过程中,乌什M_(S)7.1地震震中附近PI热点表现为“出现—逐步密集增强”,发震概率增大,该热点附近发震紧迫性和地震危险性增强。③ROC检验和R值评分显示,PI算法优于随机预测方法。④综合热点信息演化图像分析得到,南天山地震带的西南端强震危险性较高。 展开更多
关键词 乌什M_(s)7.1地震 PI算法 回溯性预测 地震热点 ROC检验
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Fast Mixture Distribution Optimization for Rain-Flow Matrix of a Steel Arch Bridge by REBMIX Algorithm
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作者 Yuliang He Weihong Lou +1 位作者 Da Hang Youhua Su 《Structural Durability & Health Monitoring》 2025年第4期887-902,共16页
The computational accuracy and efficiency of modeling the stress spectrum derived from bridge monitoring data significantly influence the fatigue life assessment of steel bridges.Therefore,determining the optimal stre... The computational accuracy and efficiency of modeling the stress spectrum derived from bridge monitoring data significantly influence the fatigue life assessment of steel bridges.Therefore,determining the optimal stress spectrum model is crucial for further fatigue reliability analysis.This study investigates the performance of the REBMIX algorithm in modeling both univariate(stress range)and multivariate(stress range and mean stress)distributions of the rain-flowmatrix for a steel arch bridge,usingAkaike’s Information Criterion(AIC)as a performance metric.Four types of finitemixture distributions—Normal,Lognormal,Weibull,and Gamma—are employed tomodel the stress range.Additionally,mixed distributions,including Normal-Normal,Lognormal-Normal,Weibull-Normal,and Gamma-Normal,are utilized to model the joint distribution of stress range and mean stress.The REBMIX algorithm estimates the number of components,component weights,and component parameters for each candidate finite mixture distribution.The results demonstrate that the REBMIX algorithm-based mixture parameter estimation approach effectively identifies the optimal distribution based on AIC values.Furthermore,the algorithm exhibits superior computational efficiency compared to traditional methods,making it highly suitable for practical applications. 展开更多
关键词 steel bridge stress spectrum finite mixture distribution REBMIX algorithm Akaike’s information criterion
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Advanced 3D Wind Farm Layout Optimization Framework via Power-Law Perturbation-Based Genetic Algorithm
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作者 Jiaru Yang Yaotong Song +3 位作者 Jun Tang Weiping Ding Zhenyu Lei Shangce Gao 《IEEE/CAA Journal of Automatica Sinica》 2025年第11期2314-2328,共15页
The modeling and optimization of wind farm layouts can effectively reduce the wake effect between turbine units,thereby enhancing the expected output power and avoiding negative influence.Traditional wind farm optimiz... The modeling and optimization of wind farm layouts can effectively reduce the wake effect between turbine units,thereby enhancing the expected output power and avoiding negative influence.Traditional wind farm optimization often uses idealized wake models,neglecting the influence of wind shear at different elevations,which leads to a lack of precision in estimating wake effects and fails to meet the accuracy and reliability requirements of practical engineering.To address this,we have constructed a three-dimensional 3D wind farm optimization model that incorporates elevation,utilizing a 3D wake model to better reflect real-world conditions.We aim to assess the optimization state of the algorithm and provide strong incentives at the right moments to ensure continuous evolution of the population.To this end,we propose an evolutionary adaptation degreeguided genetic algorithm based on power-law perturbation(PPGA)to adapt multidimensional conditions.We select the offshore wind power project in Nantong,Jiangsu,China,as a study example and compare PPGA with other well-performing algorithms under this practical project.Based on the actual wind condition data,the experimental results demonstrate that PPGA can effectively tackle this complex problem and achieve the best power efficiency. 展开更多
关键词 3D wake model China’s southeastern coast metaheuristic offshore wind farm power-law perturbation-based genetic algorithm(PPGA)
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一种基于PSO与OSTU的改进絮体分割算法 被引量:5
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作者 谢昕 王建宾 胡锋平 《传感器与微系统》 CSCD 2015年第1期131-134,共4页
介绍了图像分割中常用的直方图法、迭代法、经典大津法的阈值选取原理,然后对水处理混凝过程中的絮体图像进行分割对比实验,结合絮体运动特点和水处理实时性的要求,提出了一种基于粒子群优化(PSO)与OSTU的絮体图像分割的改进算法,即先... 介绍了图像分割中常用的直方图法、迭代法、经典大津法的阈值选取原理,然后对水处理混凝过程中的絮体图像进行分割对比实验,结合絮体运动特点和水处理实时性的要求,提出了一种基于粒子群优化(PSO)与OSTU的絮体图像分割的改进算法,即先通过灰度拉伸以增强图像灰度对比,再利用PSO算法的全局搜索能力来改善OSTU方法的阈值选取时间,求出分割阈值。实验表明:该算法能实现絮体图像的准确、快速分割,达到实时计算絮体等效粒径和数量的要求。 展开更多
关键词 粒子群优化 算法 絮体 图像分割 增强ostu
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基于细菌趋药性的Ostu双阈值图像分割算法 被引量:7
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作者 郭永芳 于明 黄凯 《计算机工程》 CAS CSCD 北大核心 2011年第22期8-11,共4页
双阈值或多阈值分割对于复杂图像具有较好的分割效果,但算法计算量较大,不适合实时应用。为此,提出一种基于细菌趋药性、利用域间最大方差的双阈值图像分割优化算法。仿真结果证明,与传统穷尽式搜索算法相比,该算法能在保证分割效果的... 双阈值或多阈值分割对于复杂图像具有较好的分割效果,但算法计算量较大,不适合实时应用。为此,提出一种基于细菌趋药性、利用域间最大方差的双阈值图像分割优化算法。仿真结果证明,与传统穷尽式搜索算法相比,该算法能在保证分割效果的前提下,降低时间复杂度。 展开更多
关键词 细菌趋药性 ostu算法 图像分割 双阈值 穷尽式搜索 优化算法
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Ostu算法的改进研究 被引量:17
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作者 梁金明 魏正曦 《四川理工学院学报(自然科学版)》 CAS 2010年第5期543-545,共3页
智能视频监控系统已经逐步应用到医院、商场等公共场合,运动目标检测算法是该智能系统的关键技术之一。文章首先从比较现有的典型运动目标检测算法出发,然后引入Ostu算法用于目标检测的图像处理过程中选取最佳阈值,最后针对其实际存在... 智能视频监控系统已经逐步应用到医院、商场等公共场合,运动目标检测算法是该智能系统的关键技术之一。文章首先从比较现有的典型运动目标检测算法出发,然后引入Ostu算法用于目标检测的图像处理过程中选取最佳阈值,最后针对其实际存在的问题,给出了一种改进方法及测试结果。 展开更多
关键词 视频智能监控 运动检测 ostu算法 运动目标
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基于麻雀算法优化的OSTU分割算法 被引量:28
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作者 李鹏 丁倩雯 《电子测量技术》 北大核心 2021年第19期148-154,共7页
针对传统最大类间差法(OSTU)在分割图像时计算量大、时间效率低的缺点,提出一种基于Singer混沌映射和随机游走策略的麻雀优化的OSTU分割方法(SRWSSA)。首先,利用Singer混沌映射改进初始化麻雀种群,增加初始麻雀种群的多样性,提高全局搜... 针对传统最大类间差法(OSTU)在分割图像时计算量大、时间效率低的缺点,提出一种基于Singer混沌映射和随机游走策略的麻雀优化的OSTU分割方法(SRWSSA)。首先,利用Singer混沌映射改进初始化麻雀种群,增加初始麻雀种群的多样性,提高全局搜索能力;其次,采用随机游走策略对更新后的最优麻雀进行扰动变异,进一步增加种群多样性,增强局部搜索能力;最后,使用提出的优化算法对标准图像进行二维OSTU分割,得到最优阈值分割图像。结果表明,所提出的SRWSSA算法在寻优能力和迭代时间上均得到了明显改善,迭代次数较PSO-OSTU、SSA-OSTU分别减少了83.3%、76%,图像峰值信噪比分别提高了8.2%、11.3%,运行时间上也有所提高,具有一定的可行性。 展开更多
关键词 麻雀搜索算法 图像分割 ostu算法 群智能优化算法
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双阈值Ostu算法的侧扫声纳图像分割 被引量:3
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作者 许枫 苏瑞文 +1 位作者 张纯 安旭东 《网络新媒体技术》 2015年第6期14-20,共7页
为了利用侧扫声纳进行水下目标的探测和识别,首先必须将声纳图像分为亮点、阴影和背景三部分。由于多数侧扫声纳图像各部分灰度对比较明显,所以适合采用阈值分割的方法进行图像分割。本文针对基本的Ostu阈值提取算法,提出了改进的双阈值... 为了利用侧扫声纳进行水下目标的探测和识别,首先必须将声纳图像分为亮点、阴影和背景三部分。由于多数侧扫声纳图像各部分灰度对比较明显,所以适合采用阈值分割的方法进行图像分割。本文针对基本的Ostu阈值提取算法,提出了改进的双阈值Ostu算法,从而满足将图像分为三部分的需求,得到分割阈值。在Ostu算法中,除了使用灰度均值,还使用了灰度方差作为特征量对阈值进行了自动提取。然后根据侧扫声纳图像的特征提出了一种快速分割的算法,将提取的阈值应用到该算法中,成功地将侧扫声纳的亮点和阴影在复杂的背景噪声中分割提取出来。并且发现方差比均值更适合用于Ostu算法进行图像分割,得到的分割效果更好,提高了算法的正确性和合理性。 展开更多
关键词 侧扫声纳图像 图像分割 ostu 快速分割算法
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基于改进Otsu算法的原油蒸馏塔金属腐蚀小目标检测仿真 被引量:1
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作者 李英波 刘凤花 李娜 《金属功能材料》 2025年第1期87-91,共5页
受到光照条件以及背景复杂度等多种因素的影响,金属腐蚀区域与背景区域混合,待检测区域较大,导致腐蚀检测质量不佳,信噪比较高,对此,提出基于改进Otsu算法的原油蒸馏塔金属腐蚀小目标检测方法。采用二维函数,对图像亮度进行描述,结合双... 受到光照条件以及背景复杂度等多种因素的影响,金属腐蚀区域与背景区域混合,待检测区域较大,导致腐蚀检测质量不佳,信噪比较高,对此,提出基于改进Otsu算法的原油蒸馏塔金属腐蚀小目标检测方法。采用二维函数,对图像亮度进行描述,结合双边滤波算法提取出光照分量,引入伽马因子以及亮度均值,对光照分量进行校正。在原有分割标准的基础上,加入颜色特征与以及纹理特征参数,结合类间方差构建出分割阈值,从而实现金属腐蚀区域与背景区域的分离处理。将金属区域分割结果划分为不同的子单元,结合疑似腐蚀检验系数对每个子单元进行判断,通过迭代,更新腐蚀区域聚类中心,结合光照分量,输出腐蚀区域检测结果。仿真结果表明,该方法应用后,金属腐蚀图像处理信噪比更高,可以在每个单元下识别出重度腐蚀区域,并具备更为精准的检测效果。 展开更多
关键词 蒸馏塔 金属腐蚀图像 检测方法 ostu算法 聚类中心 分割阈值
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基于正规基的大规模S盒FPGA设计与实现
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作者 张磊 李国元 +2 位作者 洪睿鹏 王建新 肖超恩 《密码学报(中英文)》 北大核心 2025年第4期854-869,共16页
传统上的分组密码S盒硬件实现采用查表法,其实现效果受到芯片资源的限制.针对16-bit大规模S盒在FPGA硬件实现中资源消耗大的问题,本文提出了基于复合域中正规基的S盒构造方法,研究使用较少的硬件资源实现16-bit S盒.首先,设计了基于复... 传统上的分组密码S盒硬件实现采用查表法,其实现效果受到芯片资源的限制.针对16-bit大规模S盒在FPGA硬件实现中资源消耗大的问题,本文提出了基于复合域中正规基的S盒构造方法,研究使用较少的硬件资源实现16-bit S盒.首先,设计了基于复合域的16-bit S盒构造实现方案,构建了线性的同构映射矩阵及其逆矩阵.其次,通过映射矩阵使有限域GF(2^(16))的乘法逆转换到复合域GF((((2^(2))^(2))^(2))^(2))上,进而将非线性的高维乘法逆简化为低维子域运算.然后,通过分析各级复合域不同参数对S盒实现的影响,筛选最优参数.最后,结合所提出的16-bit S盒构造实现框架,本文利用Xilinx公司的Vivado开发工具,以MK-3算法的16-bit S盒为例进行了FPGA仿真验证与性能分析.结果表明,本文构造方法实现的MK-3算法S盒需要186个LUT,时钟频率为114.129 MHz,在时钟频率/LUT的性能指标下达到了0.61360.同目前已公开文献同类方法中的最优实现性能0.43538相比,性能提升了40.93%.本文的16-bit S盒实现方案能够在降低硬件资源消耗的同时保持密码算法较高的运行频率,对有基于有限域构造的S盒的高效软硬件实现具有一定的参考价值. 展开更多
关键词 大规模s 复合域 正规基 MK-3算法 FPGA
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Smooth constraint inversion technique in genetic algorithms and its application to surface wave study in the Tibetan Plateau 被引量:3
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作者 吴建平 明跃红 曾融生 《Acta Seismologica Sinica(English Edition)》 EI CSCD 2001年第1期49-57,共9页
Smooth constraint is important in linear inversion, but it is difficult to apply directly to model parameters in genetic algorithms. If the model parameters are smoothed in iteration, the diversity of models will be g... Smooth constraint is important in linear inversion, but it is difficult to apply directly to model parameters in genetic algorithms. If the model parameters are smoothed in iteration, the diversity of models will be greatly suppressed and all the models in population will tend to equal in a few iterations, so the optimal solution meeting requirement can not be obtained. In this paper, an indirect smooth constraint technique is introduced to genetic inversion. In this method, the new models produced in iteration are smoothed, then used as theoretical models in calculation of misfit function, but in process of iteration only the original models are used in order to keep the diversity of models. The technique is effective in inversion of surface wave and receiver function. Using this technique, we invert the phase velocity of Raleigh wave in the Tibetan Plateau, revealing the horizontal variation of S wave velocity structure near the center of the Tibetan Plateau. The results show that the S wave velocity in the north is relatively lower than that in the south. For most paths there is a lower velocity zone with 12-25 km thick at the depth of 15-40 km. The lower velocity zone in upper mantle is located below the depth of 100 km, and the thickness is usually 40-80 km, but for a few paths reach to 100 km thick. Among the area of Ando, Maqi and Ushu stations, there is an obvious lower velocity zone with the lowest velocity of 4.2-4.3 km/s at the depth of 90-230 km. Based on the S wave velocity structures of different paths and former data, we infer that the subduction of the Indian Plate is delimited nearby the Yarlung Zangbo suture zone. 展开更多
关键词 genetic algorithm smooth constraint surface wave s wave velocity structure Tibetan Plateau
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A hybrid quantum encoding algorithm of vector quantization for image compression 被引量:4
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作者 庞朝阳 周正威 郭光灿 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第12期3039-3043,共5页
Many classical encoding algorithms of vector quantization (VQ) of image compression that can obtain global optimal solution have computational complexity O(N). A pure quantum VQ encoding algorithm with probability... Many classical encoding algorithms of vector quantization (VQ) of image compression that can obtain global optimal solution have computational complexity O(N). A pure quantum VQ encoding algorithm with probability of success near 100% has been proposed, that performs operations 45√N times approximately. In this paper, a hybrid quantum VQ encoding algorithm between the classical method and the quantum algorithm is presented. The number of its operations is less than √N for most images, and it is more efficient than the pure quantum algorithm. 展开更多
关键词 vector quantization Grover's algorithm image compression quantum algorithm
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Hydraulic Optimization of a Double-channel Pump's Impeller Based on Multi-objective Genetic Algorithm 被引量:12
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作者 ZHAO Binjuan WANG Yu +2 位作者 CHEN Huilong QIU Jing HOU Duohua 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2015年第3期634-640,共7页
Computational fluid dynamics(CFD) can give a lot of potentially very useful information for hydraulic optimization design of pumps, however, it cannot directly state what kind of modification should be made to impro... Computational fluid dynamics(CFD) can give a lot of potentially very useful information for hydraulic optimization design of pumps, however, it cannot directly state what kind of modification should be made to improve such hydrodynamic performance. In this paper, a more convenient and effective approach is proposed by combined using of CFD, multi-objective genetic algorithm(MOGA) and artificial neural networks(ANN) for a double-channel pump's impeller, with maximum head and efficiency set as optimization objectives, four key geometrical parameters including inlet diameter, outlet diameter, exit width and midline wrap angle chosen as optimization parameters. Firstly, a multi-fidelity fitness assignment system in which fitness of impellers serving as training and comparison samples for ANN is evaluated by CFD, meanwhile fitness of impellers generated by MOGA is evaluated by ANN, is established and dramatically reduces the computational expense. Then, a modified MOGA optimization process, in which selection is performed independently in two sub-populations according to two optimization objectives, crossover and mutation is performed afterword in the merged population, is developed to ensure the global optimal solution to be found. Finally, Pareto optimal frontier is found after 500 steps of iterations, and two optimal design schemes are chosen according to the design requirements. The preliminary and optimal design schemes are compared, and the comparing results show that hydraulic performances of both pumps 1 and 2 are improved, with the head and efficiency of pump 1 increased by 5.7% and 5.2%, respectively in the design working conditions, meanwhile shaft power decreased in all working conditions, the head and efficiency of pump 2 increased by 11.7% and 5.9%, respectively while shaft power increased by 5.5%. Inner flow field analyses also show that the backflow phenomenon significantly diminishes at the entrance of the optimal impellers 1 and 2, both the area of vortex and intensity of vortex decreases in the whole flow channel. This paper provides a promising tool to solve the hydraulic optimization problem of pumps' impellers. 展开更多
关键词 double-channel pump's impeller multi-objective genetic algorithm artificial neural network computational fluid dynamics(CFD) UNI
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Automatic Algorithm Programming Model Based on the Improved Morgan's Refinement Calculus 被引量:5
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作者 ZUO Zhengkang HU Ying +2 位作者 HUANG Qing WANG Yuan WANG Changjing 《Wuhan University Journal of Natural Sciences》 CAS CSCD 2022年第5期405-414,共10页
The automatic algorithm programming model can increase the dependability and efficiency of algorithm program development,including specification generation,program refinement,and formal verification.However,the existi... The automatic algorithm programming model can increase the dependability and efficiency of algorithm program development,including specification generation,program refinement,and formal verification.However,the existing model has two flaws:incompleteness of program refinement and inadequate automation of formal verification.This paper proposes an automatic algorithm programming model based on the improved Morgan’s refinement calculus.It extends the Morgan’s refinement calculus rules and designs the C++generation system for realizing the complete process of refinement.Meanwhile,the automation tools VCG(Verification Condition Generator)and Isabelle are used to improve the automation of formal verification.An example of a stock’s maximum income demonstrates the effectiveness of the proposed model.Furthermore,the proposed model has some relevance for automatic software generation. 展开更多
关键词 automatic algorithm programming model program refinement VCG IsABELLE Morgan’s refinement calculus
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DETERMINING THE STRUCTURES AND PARAMETERS OF RADIAL BASIS FUNCTION NEURAL NETWORKS USING IMPROVED GENETIC ALGORITHMS 被引量:1
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作者 Meiqin Liu Jida Chen 《Journal of Central South University》 SCIE EI CAS 1998年第2期68-73,共6页
The method of determining the structures and parameters of radial basis function neural networks(RBFNNs) using improved genetic algorithms is proposed. Akaike′s information criterion (AIC) with generalization error t... The method of determining the structures and parameters of radial basis function neural networks(RBFNNs) using improved genetic algorithms is proposed. Akaike′s information criterion (AIC) with generalization error term is used as the best criterion of optimizing the structures and parameters of networks. It is shown from the simulation results that the method not only improves the approximation and generalization capability of RBFNNs ,but also obtain the optimal or suboptimal structures of networks. 展开更多
关键词 RADIAL BAsIs function neural network GENETIC algorithms Akaike′s information CRITERION OVERFITTING
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Image Segmentation of Brain MR Images Using Otsu’s Based Hybrid WCMFO Algorithm 被引量:6
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作者 A.Renugambal K.Selva Bhuvaneswari 《Computers, Materials & Continua》 SCIE EI 2020年第8期681-700,共20页
In this study,a novel hybrid Water Cycle Moth-Flame Optimization(WCMFO)algorithm is proposed for multilevel thresholding brain image segmentation in Magnetic Resonance(MR)image slices.WCMFO constitutes a hybrid betwee... In this study,a novel hybrid Water Cycle Moth-Flame Optimization(WCMFO)algorithm is proposed for multilevel thresholding brain image segmentation in Magnetic Resonance(MR)image slices.WCMFO constitutes a hybrid between the two techniques,comprising the water cycle and moth-flame optimization algorithms.The optimal thresholds are obtained by maximizing the between class variance(Otsu’s function)of the image.To test the performance of threshold searching process,the proposed algorithm has been evaluated on standard benchmark of ten axial T2-weighted brain MR images for image segmentation.The experimental outcomes infer that it produces better optimal threshold values at a greater and quicker convergence rate.In contrast to other state-of-the-art methods,namely Adaptive Wind Driven Optimization(AWDO),Adaptive Bacterial Foraging(ABF)and Particle Swarm Optimization(PSO),the proposed algorithm has been found to be better at producing the best objective function,Peak Signal-to-Noise Ratio(PSNR),Standard Deviation(STD)and lower computational time values.Further,it was observed thatthe segmented image gives greater detail when the threshold level increases.Moreover,the statistical test result confirms that the best and mean values are almost zero and the average difference between best and mean value 1.86 is obtained through the 30 executions of the proposed algorithm.Thus,these images will lead to better segments of gray,white and cerebrospinal fluid that enable better clinical choices and diagnoses using a proposed algorithm. 展开更多
关键词 Hybrid WCMFO algorithm Otsu’s function multilevel thresholding image segmentation brain MR image
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A quantum search algorithm of two entangled registers to realize quantum discrete Fourier transform of signal processing 被引量:2
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作者 庞朝阳 胡本琼 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第9期3220-3226,共7页
The discrete Fourier transform (DFT) is the base of modern signal processing. 1-dimensional fast Fourier transform (1D FFT) and 2D FFT have time complexity O(N log N) and O(N^2 log N) respectively. Since 1965,... The discrete Fourier transform (DFT) is the base of modern signal processing. 1-dimensional fast Fourier transform (1D FFT) and 2D FFT have time complexity O(N log N) and O(N^2 log N) respectively. Since 1965, there has been no more essential breakthrough for the design of fast DFT algorithm. DFT has two properties. One property is that DFT is energy conservation transform. The other property is that many DFT coefficients are close to zero. The basic idea of this paper is that the generalized Grover's iteration can perform the computation of DFT which acts on the entangled states to search the big DFT coefficients until these big coefficients contain nearly all energy. One-dimensional quantum DFT (1D QDFT) and two-dimensional quantum DFT (2D QDFT) are presented in this paper. The quantum algorithm for convolution estimation is also presented in this paper. Compared with FFT, 1D and 2D QDFT have time complexity O(v/N) and O(N) respectively. QDFT and quantum convolution demonstrate that quantum computation to process classical signal is possible. 展开更多
关键词 Grover's algorithm entangled state DFT QDFT
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Comparative analysis of various modularization algorithms and species specific study of VEGF signaling pathways 被引量:2
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作者 Namrata Tomar Losiana Nayak Rajat K. De 《Journal of Biomedical Science and Engineering》 2010年第10期931-942,共12页
In biology, signal transduction refers to a process by which a cell converts one kind of signal or stimulus into another. It involves ordered sequences of biochemical reactions inside the cell. These cascades of react... In biology, signal transduction refers to a process by which a cell converts one kind of signal or stimulus into another. It involves ordered sequences of biochemical reactions inside the cell. These cascades of reactions are carried out by enzymes and activated by second messengers. Signal transduction pathways are complex in nature. Each pathway is responsible for tuning one or more biological functions in the intracellular environment as well as more than one pathway interact among themselves to carry forward a single biological function. Such kind of behavior of these pathways makes understanding difficult. Hence, for the sake of simplicity, they need to be partitioned into smaller modules and then analyzed. We took VEGF signaling pathway, which is responsible for angiogenesis for this kind of modularized study. Modules were obtained by applying the algorithm of Nayak and De (Nayak and De, 2007) for different complexity values. These sets of modules were compared among themselves to get the best set of modules for an optimal complexity value. The best set of modules compared with four different partitioning algorithms namely, Farhat’s (Farhat, 1998), Greedy (Chartrand and Oellermann, 1993), Kernighan-Lin’s (Kernighan and Lin, 1970) and Newman’s community finding algorithm (Newman, 2006). These comparisons enabled us to decide which of the aforementioned algorithms was the best one to create partitions from human VEGF signaling pathway. The optimal complexity value, on which the best set of modules was obtained, was used to get modules from different species for comparative study. Comparison among these modules would shed light on the trend of development of VEGF signaling pathway over these species. 展开更多
关键词 signal TRANsDUCTION PATHWAY VEGF PATHWAY Complexity Value KEGG Database MODULARIZATION Newman’s Community Finding algorithm Kernighan-Lin’s algorithm Farhat’s algorithm and GREEDY algorithm.
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Routing Protocol Based on Grover’s Searching Algorithm for Mobile Ad-hoc Networks 被引量:3
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作者 孟利民 宋文波 《China Communications》 SCIE CSCD 2013年第3期145-156,共12页
In Mobile Ad-hoc Networks (MANETs), routing protocols directly affect various indices of network Quality of Service (QoS), so they play an important role in network performance. To address the drawbacks associated wit... In Mobile Ad-hoc Networks (MANETs), routing protocols directly affect various indices of network Quality of Service (QoS), so they play an important role in network performance. To address the drawbacks associated with traditional routing protocols in MANETs, such as poor anti-fading performance and slow convergence rate, for basic Dynamic Source Routing (DSR), we propose a new routing model based on Grover's searching algorithm. With this new routing model, each node maintains a node vector function, and all the nodes can obtain a node probability vector using Grover's algorithm, and then select an optimal routing according to node probability. Simulation results show that compared with DSR, this new routing protocol can effectively extend the network lifetime, as well as reduce the network delay and the number of routing hops. It can also significantly improve the anti-jamming capability of the network. 展开更多
关键词 Grover's channel fading additive bit error rate searching algorithm noise network delay
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Design of quantum VQ iteration and quantum VQ encoding algorithm taking O(√N) steps for data compression 被引量:2
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作者 庞朝阳 周正威 +1 位作者 陈平形 郭光灿 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第3期618-623,共6页
Vector quantization (VQ) is an important data compression method. The key of the encoding of VQ is to find the closest vector among N vectors for a feature vector. Many classical linear search algorithms take O(N)... Vector quantization (VQ) is an important data compression method. The key of the encoding of VQ is to find the closest vector among N vectors for a feature vector. Many classical linear search algorithms take O(N) steps of distance computing between two vectors. The quantum VQ iteration and corresponding quantum VQ encoding algorithm that takes O(√N) steps are presented in this paper. The unitary operation of distance computing can be performed on a number of vectors simultaneously because the quantum state exists in a superposition of states. The quantum VQ iteration comprises three oracles, by contrast many quantum algorithms have only one oracle, such as Shor's factorization algorithm and Grover's algorithm. Entanglement state is generated and used, by contrast the state in Grover's algorithm is not an entanglement state. The quantum VQ iteration is a rotation over subspace, by contrast the Grover iteration is a rotation over global space. The quantum VQ iteration extends the Grover iteration to the more complex search that requires more oracles. The method of the quantum VQ iteration is universal. 展开更多
关键词 data compression vector quantization Grover's algorithm quantum VQ iteration
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