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一种基于距离变换的不规则区域匹配算法
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作者 霍占强 朱婷 +1 位作者 刘红敏 王志衡 《计算机工程与科学》 CSCD 北大核心 2016年第7期1471-1478,共8页
针对不规则区域难以直接匹配的问题,提出了一种新颖的不规则区域匹配算法,即基于距离变换的不规则区域描述子DTIRD。为了避免椭圆拟合误差和主方向不准确产生的匹配错误,该算法采用区域边界附近纹理和区域内部纹理确定不规则区域的支撑... 针对不规则区域难以直接匹配的问题,提出了一种新颖的不规则区域匹配算法,即基于距离变换的不规则区域描述子DTIRD。为了避免椭圆拟合误差和主方向不准确产生的匹配错误,该算法采用区域边界附近纹理和区域内部纹理确定不规则区域的支撑区域;然后给出了一种基于距离变换的子区域划分方法,与传统方法相比,能够减少图像亮度变化带来的匹配错误;最后针对区域存在形状、尺寸大小不一且具有不同像素点数的问题,采用均值标准差MS构造描述算法。实验结果表明,该算法对旋转、光照、模糊以及压缩变化图像具有更好的匹配性能。 展开更多
关键词 不规则区域 支撑区域 距离变换 子区域划分 区域匹配 均值标准差算法
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测量精度约束的模糊度搜索定位算法
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作者 鲜炜 杨杰 吴绩伟 《计算机应用研究》 CSCD 北大核心 2023年第7期2053-2059,共7页
为了快速且准确地固定整周模糊度,针对LAMBDA算法存在整周模糊度搜索范围过广、搜索效率低等问题,提出一种基于测量精度约束的模糊度搜索算法。该算法在最小二乘问题得到最佳加权的情况下,以标准差分进化(DE)算法为基础、载波相位测量... 为了快速且准确地固定整周模糊度,针对LAMBDA算法存在整周模糊度搜索范围过广、搜索效率低等问题,提出一种基于测量精度约束的模糊度搜索算法。该算法在最小二乘问题得到最佳加权的情况下,以标准差分进化(DE)算法为基础、载波相位测量精度为约束条件进行模糊度固定解的检验。该算法解决了不同卫星高度角产生的影响,在解算三维整周模糊度时能够达到99%的解算成功率。相比于MLAMBDA、DE、自适应加权的差分进化(AWDE)算法,该算法进一步提高了模糊度的解算效率和成功率。 展开更多
关键词 整周模糊度 测量精度约束 模糊度搜索算法 最小二乘 标准差分进化算法
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差分进化算法的改进研究
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作者 蒋兵兵 《信息记录材料》 2022年第4期210-213,共4页
标准差分进化算法在算法精度等方面存在缺陷,需要结合实际应用需求完成算法改进。在把握差分进化算法原理和流程的基础上,从控制参数调整、操作算子改进等方面提出了算法的改进方法,并结合约束优化问题进行了实践探索,提出了基于广义反... 标准差分进化算法在算法精度等方面存在缺陷,需要结合实际应用需求完成算法改进。在把握差分进化算法原理和流程的基础上,从控制参数调整、操作算子改进等方面提出了算法的改进方法,并结合约束优化问题进行了实践探索,提出了基于广义反向学习策略和自适应权衡模型改进算法,最终通过测试验证了算法的有效性,以供参考。 展开更多
关键词 标准差分进化算法 控制参数调整 操作算子改进 种群结构优化
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激光散斑的亚像素位移法计算及比较 被引量:10
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作者 王希军 《中国光学》 EI CAS 2012年第6期652-657,共6页
根据激光散斑相关测量中采用的插值法、梯度算法和牛顿-拉夫森迭代法3种亚像素位移算法的特点,逐一在亚像素尺度计算出磁流体干燥过程中的同一激光散斑图的偏均值和标准差变化曲线。基于得到的偏差均值和标准差讨论了3种算法处理激光散... 根据激光散斑相关测量中采用的插值法、梯度算法和牛顿-拉夫森迭代法3种亚像素位移算法的特点,逐一在亚像素尺度计算出磁流体干燥过程中的同一激光散斑图的偏均值和标准差变化曲线。基于得到的偏差均值和标准差讨论了3种算法处理激光散斑图的特点,比较了3种算法处理散斑图的计算精度、稳定性和计算用时。结果显示,在小变形的亚像素位移测量时,梯度算法的精度较高,且较为稳定,计算效率也较牛顿-拉夫森算法快约9倍。因此,在进行小变形亚像素位移测量时,采用梯度算法计算激光散斑是有效的。 展开更多
关键词 激光散斑 亚像素计算 算法标准差
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Automatically detecting auditory P300 in several trials 被引量:1
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作者 莫少锋 汤井田 陈洪波 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第6期2201-2206,共6页
A method was demonstrated based on Infomax independent component analysis(Infomax ICA) for automatically extracting auditory P300 signals within several trials. A signaling equilibrium algorithm was proposed to enhanc... A method was demonstrated based on Infomax independent component analysis(Infomax ICA) for automatically extracting auditory P300 signals within several trials. A signaling equilibrium algorithm was proposed to enhance the effectiveness of the Infomax ICA decomposition. After the mixed signal was decomposed by Infomax ICA, the independent component(IC) used in auditory P300 reconstruction was automatically chosen by using the standard deviation of the fixed temporal pattern. And the result of auditory P300 was reconstructed using the selected ICs. The experimental results show that the auditory P300 can be detected automatically within five trials. The Pearson correlation coefficient between the standard signal and the signal detected using the proposed method is significantly greater than that between the standard signal and the signal detected using the average method within five trials. The wave pattern result obtained using the proposed algorithm is better and more similar to the standard signal than that obtained by the average method for the same number of trials. Therefore, the proposed method can automatically detect the effective auditory P300 within several trials. 展开更多
关键词 independent component analysis (ICA) auditory P300: fixed temporal patltern several trials event-related potentials
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A new heuristic for task scheduling in heterogeneous computing environment
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作者 Ehsan Ullah MUNIR Jian-zhong LI +2 位作者 Sheng-fei SHI Zhao-nian ZOU Qaisar RASOOL 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2008年第12期1715-1723,共9页
Heterogeneous computing (HC) environment utilizes diverse resources with different computational capabilities to solve computing-intensive applications having diverse computational requirements and constraints. The ta... Heterogeneous computing (HC) environment utilizes diverse resources with different computational capabilities to solve computing-intensive applications having diverse computational requirements and constraints. The task assignment problem in HC environment can be formally defined as for a given set of tasks and machines, assigning tasks to machines to achieve the minimum makespan. In this paper we propose a new task scheduling heuristic, high standard deviation first (HSTDF), which considers the standard deviation of the expected execution time of a task as a selection criterion. Standard deviation of the ex- pected execution time of a task represents the amount of variation in task execution time on different machines. Our conclusion is that tasks having high standard deviation must be assigned first for scheduling. A large number of experiments were carried out to check the effectiveness of the proposed heuristic in different scenarios, and the comparison with the existing heuristics (Max-min, Sufferage, Segmented Min-average, Segmented Min-min, and Segmented Max-min) clearly reveals that the proposed heuristic outperforms all existing heuristics in terms of average makespan. 展开更多
关键词 Heterogeneous computing Task scheduling Greedy heuristics High standard deviation first (HSTDF) heuristic
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基于异窗宽GTWR模型的商品住宅价格影响因素研究 被引量:1
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作者 侯健 王芝皓 +1 位作者 田茂再 窦燕 《数理统计与管理》 CSSCI 北大核心 2022年第6期1003-1014,共12页
随着数据可获得性的增强,时空数据被广泛地应用在各个领域。以中国西部干旱区代表城市乌鲁木齐为研究对象,本文根据标准差椭圆加权算法与时空地理加权回归模型(GTWR)提出异窗宽GTWR模型对房屋价格变动影响因素的时空变化进行研究。结果... 随着数据可获得性的增强,时空数据被广泛地应用在各个领域。以中国西部干旱区代表城市乌鲁木齐为研究对象,本文根据标准差椭圆加权算法与时空地理加权回归模型(GTWR)提出异窗宽GTWR模型对房屋价格变动影响因素的时空变化进行研究。结果表明乌鲁木齐市住房价格的变动存在着明显的空间异质性,异窗宽GTWR模型对其的解释能力较好,标准差椭圆加权算法有效的减少了计算量,房价变动在空间上受交通便利性和绿化率等因素的影响较大,时间上受建筑年龄因素影响较大。 展开更多
关键词 时空数据 干旱区商品住宅 空间异质性 标准差椭圆算法 异窗宽时空地理加权回归模型
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Simultaneous and interference-free determination of eleven nonsteroidal anti-inflammatory drugs illegally added into Chinese patent drugs using chemometrics-assisted HPLC-DAD strategy 被引量:2
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作者 Tong Wang Hai-Long Wu +5 位作者 Li-Xia Xie Zhi Liu Wan-Jun Long Li Cheng Yu-Jie Ding Ru-Qin Yu 《Science China Chemistry》 SCIE EI CAS CSCD 2018年第6期739-749,共11页
In this work, a smart strategy that combines three-way high performance liquid chromatography-diode array detection(HPLCDAD) data with second-order calibration method based on alternating trilinear decomposition(ATLD)... In this work, a smart strategy that combines three-way high performance liquid chromatography-diode array detection(HPLCDAD) data with second-order calibration method based on alternating trilinear decomposition(ATLD) algorithm was proposed for simultaneous determination of eleven non-steroidal anti-inflammatory drugs(NSAIDs) illegally added into Chinese patent drugs and health products. All target analytes were rapidly eluted out within 14.5 min under a simple gradient elution. With the aid of the prominent "second-order advantage" of the ATLD algorithm, three HPLC problems, i.e. peak overlaps, unknown interferences and baseline drift, could be mathematically calibrated, and pure signals of target analytes could be extracted out from heavy-interference but information-rich HPLC-DAD data. The average spiked recoveries for all target analytes were in the range of 95.9%–106.4% with standard deviations lower than 7.5%. Validation parameters including sensitivity(SEN), selectivity(SEL), limit of detection(LOD), limit of quantitation(LOQ) and precisions of intra-day and inter-day were calculated to validate the accuracy of the proposed method, quantitative results were further confirmed by the classic HPLC method, which proved that chemometrics-assisted HPLC-DAD analytical strategy was highly efficient, accurate and green for drug-abuse monitoring of NSAIDs in Chinese patent drugs and health products. 展开更多
关键词 non-steroidal anti-inflammatory drugs Chinese patent drugs high performance liquid chromatography-diode array detection second-order calibration alternating trilinear decomposition
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