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Gray code based gradient-free optimization algorithm for parameterized quantum circuit
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作者 张安琪 武春辉 赵生妹 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期189-194,共6页
A Gray code based gradient-free optimization(GCO)algorithm is proposed to update the parameters of parameterized quantum circuits(PQCs)in this work.Each parameter of PQCs is encoded as a binary string,named as a gene,... A Gray code based gradient-free optimization(GCO)algorithm is proposed to update the parameters of parameterized quantum circuits(PQCs)in this work.Each parameter of PQCs is encoded as a binary string,named as a gene,and a genetic-based method is adopted to select the offsprings.The individuals in the offspring are decoded in Gray code way to keep Hamming distance,and then are evaluated to obtain the best one with the lowest cost value in each iteration.The algorithm is performed iteratively for all parameters one by one until the cost value satisfies the stop condition or the number of iterations is reached.The GCO algorithm is demonstrated for classification tasks in Iris and MNIST datasets,and their performance are compared by those with the Bayesian optimization algorithm and binary code based optimization algorithm.The simulation results show that the GCO algorithm can reach high accuracies steadily for quantum classification tasks.Importantly,the GCO algorithm has a robust performance in the noise environment. 展开更多
关键词 gradient-free optimization gray code genetic-based method
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Optimization of short-circuit transition parameters of Q235B steel GMAW based on orthogonal gray relational analysis
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作者 陈昌荣 唐宝林 +2 位作者 叶宇杰 练国富 黄旭 《China Welding》 CAS 2024年第2期39-49,共11页
In gas metal arc welding(GMAW)process,the short-circuit transition was the most typical transition observed in molten metal droplets.This paper used orthogonal tests to explore the coupling effect law of welding proce... In gas metal arc welding(GMAW)process,the short-circuit transition was the most typical transition observed in molten metal droplets.This paper used orthogonal tests to explore the coupling effect law of welding process parameters on the quality of weld forming under short-circuit transition,the design of 3 factors and 3 levels of a total of 9 groups of orthogonal tests,welding current,welding voltage,welding speed as input parameters:effective area ratio,humps,actual linear power density,aspect ratio,Vickers hardness as output paramet-ers(response targets).Using range analysis and trend charts,we can visually depict the relationship between input parameters and a single output parameter,ultimately determining the optimal process parameters that impact the single output index.Then combined with gray the-ory to transform the three response targets into a single gray relational grade(GRG)for analysis,the optimal combination of the weld mor-phology parameters as follows:welding current 100 A,welding voltage 25 V,welding speed 30 cm/min.Finally,validation experiments were conducted,and the results showed that the error between the gray relational grade and the predicted value was 2.74%.It was observed that the effective area ratio of the response target significantly improved,validating the reliability of the orthogonal gray relational method. 展开更多
关键词 short-circuit transition orthogonal test gray relational forming quality
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顺应论视域下The Picture of Dorian Gray中译本的对比研究
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作者 滕璐 《现代语言学》 2024年第6期265-271,共7页
The Picture of Dorian Gray是王尔德唯一一部长篇小说,小说语言唯美自然。本文从顺应论的角度出发,从语境顺应、结构顺应以及动态顺应三个方面分析孙宜学译本与荣如德译本的差异。文章发现,两译者对于自己的定位不同,即前者是源语文化... The Picture of Dorian Gray是王尔德唯一一部长篇小说,小说语言唯美自然。本文从顺应论的角度出发,从语境顺应、结构顺应以及动态顺应三个方面分析孙宜学译本与荣如德译本的差异。文章发现,两译者对于自己的定位不同,即前者是源语文化的传播者,后者则是文学作品的传播者,译者的意识程度以及自身定位影响着译者采取的翻译方法,只有找准定位才能更好地翻译,获得更大的阅读价值以及参考价值。 展开更多
关键词 The Picture of Dorian gray 英汉对比 顺应论 翻译对比
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ANALYSIS ON GRAY NODES AND GRAYNESS DEGREE IN COMPLEX NETWORK 被引量:1
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作者 崔博 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2012年第2期125-130,共6页
Based on the theory of complex network and gray system, the sugesstion that there exist two types of gray nodes in complex networks, Gray Node I and Gray Node II, is concluded. The first one refers to the existent unk... Based on the theory of complex network and gray system, the sugesstion that there exist two types of gray nodes in complex networks, Gray Node I and Gray Node II, is concluded. The first one refers to the existent unknown gray nodes, and the second the evolution gray nodes. The relevant definitions are also given. Further- more, grayness degree in complex networks is described and divided into two forms--the relative grayness degree (RGD) and the absolute grayness degree (AGD), which are proved respectively. 展开更多
关键词 gray system complex network gray nodes grayness degree
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Characterization and Pathogenicity of Pseudopestalotiopsis vietnamensis Causing Gray Blight of Wuyi Rock Tea(Camellia sinensis)in China and Specific Mechanisms of Disease Infection 被引量:1
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作者 Guangheng Wu Lu Rui +6 位作者 Xiang Lu Libo Han Gan Lv Xianyu Fu Jinxian Liu Nong Zhou Chuanhai Zhang 《Phyton-International Journal of Experimental Botany》 SCIE 2023年第1期131-147,共17页
Gray blight disease(GBD)causes significant losses in tea production in China.Although genes and biological processes involved in resistance to fungal disease in tea plants have been identified,specific mechanisms of t... Gray blight disease(GBD)causes significant losses in tea production in China.Although genes and biological processes involved in resistance to fungal disease in tea plants have been identified,specific mechanisms of the GBD infection process remain unknown.In this study,morphological and multi-gene(TEF-TUB-ITS)phylogenetic characteristics were used to identify isolate CLBB1 of Pseudopestalotiopsis vietnamensis.Pathogenicity tests confirmed that isolate CLBB1 from tea leaves caused GBD in the susceptible tea cultivar Wuyi Rock(Camellia sinensis var.sinensis cv.Shuixian).Spores began to germinate 24 h after infection(hai),and after 48 h,elongated fungal hyphae formed from a single conidium.Transcriptome analysis revealed that 482,517,and 369 genes were differentially expressed at 24,48,and 72 hai,respectively,in Wuyi Rock tea leaves.Isolate CLBB1 infection elicited phenotype-related responses and activated defense-related pathways,including plant–pathogen interaction,MAPK signaling,and plant hormone signal transduction,suggesting a possible mechanism underlying phenotype-based susceptibility to CLBB1.Thus,a new Ps.vietnamensis strain causing GBD in the tea cultivar‘Shuixian’was discovered in this study.Transcriptome analysis indicated that pathogen invasion activated chitin-related MAPK pathways and that tea plants required a hormone to restrict CLBB1. 展开更多
关键词 Chitin-related MAPK pathways gray blight disease Pseudopestalotiopsis TEA transcriptional analysis
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一种广义Gray码及其在数字图像置乱中的应用 被引量:1
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作者 王广超 罗来鹏 《赣南师范学院学报》 2007年第3期41-44,共4页
以图像的信息安全问题为背景,提出了一种新的广义Gray码,讨论了该码在数字图像置乱中的应用.实验表明该序码变换在数字图像置乱方面效果明显.
关键词 gray 广义gray 置乱广义gray 置乱变换 信息安全
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Analysis of the Relationship between Mechanical Properties and Pore Structure of MSW Incineration Bottom Ash Fine Aggregate Concrete after Freeze-Thaw Cycles Based on the Gray Theory
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作者 Peng Zhang Dongsheng Shi +1 位作者 Ping Han Wenchao Jiang 《Journal of Renewable Materials》 SCIE EI 2023年第2期669-688,共20页
The destruction of concrete building materials in severely cold regions of the north is more severely affected by freeze-thaw cycles,and the relationship between the mechanical properties and pore structure of concret... The destruction of concrete building materials in severely cold regions of the north is more severely affected by freeze-thaw cycles,and the relationship between the mechanical properties and pore structure of concrete with fine aggregate from municipal solid waste(MSW)incineration bottom ash after freeze-thaw cycles is analyzed under the degree of freeze-thaw hazard variation.In this paper,the gray correlation method is used to calculate the correlation between the relative dynamic elastic modulus,compressive strength,and microscopic porosity parameters to speculate on the most important factors affecting their changes.The GM(1,1)model was established based on the compressive strength of the waste incineration ash aggregate concrete,the relative error between the simulated and actual values in the model was less than 5%,and the accuracy of the model was level 1,indicating that the GM(1,1)model can well reflect the change in the compressive strength of the MSW incineration bottom ash aggregate concrete during freeze-thaw cycles.Using the gray correlation method,the correlation between the relative dynamic elastic modulus,compressive strength,air content,specific surface area,pore spacing coefficient,and pore average chord length was calculated,and the pore spacing coefficient and pore average chord length were determined to be highly correlated with each other.This determination can help analyze and infer the deterioration mechanism of concrete subject to freeze-thaw cycles.These results can provide a theoretical basis for guiding the engineering practice of concrete with fine aggregates of household bottom ash in the northern cold region. 展开更多
关键词 Municipal solid waste incineration bottom ash CONCRETE gray system theory mechanical properties pore structure
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Welding Effect at the Heat Affected Zone by Joining a Gray Cast Iron with Stainless Steel E308-16
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作者 Yajaira Curiel-Razo Enrique Curiel-Reyna +2 位作者 Minerva Robles-Agudo Alberto Lara-Guevara Ignacio Rojas-Rodríguez 《Materials Sciences and Applications》 2023年第6期336-345,共10页
Different investigations of the union of dissimilar materials such as stainless steel and different castings have been carried out, but rapid cooling immediately after welding has not been considered, in this work it ... Different investigations of the union of dissimilar materials such as stainless steel and different castings have been carried out, but rapid cooling immediately after welding has not been considered, in this work it was investigated how rapid cooling affects the metallurgical microstructure and consequently the mechanical properties. The effect of welding parameters on the microstructure and mechanical properties of the joint between dissimilar metals, an E-308-16 austenitic stainless steel and Gray Cast Iron was also analyzed. Gray cast iron samples (GCI) were fabricated, welded and cooled. The main welding parameters studied in this work are the welding technique and the type of filler electrodes. Flux-coated electrode E-308-16 was applied for this different joint. An experimental study was carried out for the analysis of welded joints of similar and dissimilar steels. The microstructure of the welded joints was analyzed using an optical microscope, in the base metals, heat affected zone (HAZ) and filler metal. The mechanical properties of the welded joints were evaluated by Vickers microhardness and tensile strength tests. The hardness profile showed differences in hardness between the base metals, the heat affected zone and the filler metal. The metallurgical microstructures observed along the welded areas corresponded to the profile. The hardness differences determined the effect on the mechanical and metallurgical characteristics of the welded samples as a result of the cooling rate differences. This research work is important because it allows us to analyze the possibility of reworking pieces of dissimilar materials by welding or, failing that, to determine if this may or may not be possible. 展开更多
关键词 gray Iron WELDING Hot Affected Zone Filler Metal Microstructure Dissimilar Metals
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Henry Vandyke Carter (1831-1897): the forgotten co-author of Gray’s Anatomy
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作者 Rafael Romero-Reverón 《History & Philosophy of Medicine》 2023年第4期10-12,共3页
Henry Vandyke Carter(1831–1897),physician and illustrator from Saint George’s Hospital in London,England.He worked with Henry Williamson Gray(1827–1861)on anatomical dissections and Carter’s illustrations contribu... Henry Vandyke Carter(1831–1897),physician and illustrator from Saint George’s Hospital in London,England.He worked with Henry Williamson Gray(1827–1861)on anatomical dissections and Carter’s illustrations contributed significantly to the success of the Treaty of Anatomy,Descriptive and Surgical.Henry Carter never achieved any credit or royalty for his work.This book is currently regarded as one of the most influential human anatomy textbooks.The paper aims to present a brief review of Henry Carter’s contributions to the medical field. 展开更多
关键词 ANATOMY ENGLAND Henry Vandyke Carter gray’s Anatomy medical education PROFESSOR
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环F_4+uF_4上线性码及其对偶码的Gray像 被引量:1
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作者 刘修生 刘花璐 《通信学报》 EI CSCD 北大核心 2012年第8期134-137,共4页
研究了环F4+uF4与域F4上的线性码,利用环F4+uF4上码C的Gray重量wG,Gray距离d G和(F4+uF4)n到F4 2n的Gray映射φ,证明了环F4+uF4上线性码C及其对偶码的Gray像φ(C)为F4上的线性码和对偶且dH G(φ(C))dG(C)。同时,给出了F4+uF4上循环码C的... 研究了环F4+uF4与域F4上的线性码,利用环F4+uF4上码C的Gray重量wG,Gray距离d G和(F4+uF4)n到F4 2n的Gray映射φ,证明了环F4+uF4上线性码C及其对偶码的Gray像φ(C)为F4上的线性码和对偶且dH G(φ(C))dG(C)。同时,给出了F4+uF4上循环码C的Gray像φ(C)为F4上的2-拟循环码。 展开更多
关键词 线性码 对偶码 gray重量 gray映射
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基于Anti-Gray映射的4D-QPSK星座设计
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作者 郭常盈 梁云英 方伟伟 《通信技术》 2015年第7期776-779,共4页
多维映射通过增加星座的维度数而使得符号间的平均欧式距离大大增加,这可以大程度地提高数字通信系统的可靠性。然而已有的基于Gray映射的4D-QPSK星座在设计上,并没有充分利用四维星座的空间优势,对于相邻星座点的汉明距离并未达到最大... 多维映射通过增加星座的维度数而使得符号间的平均欧式距离大大增加,这可以大程度地提高数字通信系统的可靠性。然而已有的基于Gray映射的4D-QPSK星座在设计上,并没有充分利用四维星座的空间优势,对于相邻星座点的汉明距离并未达到最大。提出一种基于Anti-Gray映射的4D-QPSK星座设计方案,该方案中的比特映射方式按照相邻星座点汉明距离最大,汉明距离为1的星座点欧式距离最大的设计原则,使星座点间具有最大的分集度。仿真结果表明,该方案可以提高抵抗衰落信道的能力。 展开更多
关键词 gray映射 Anti-gray映射 多维映射 4D-QPSK
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基于Gray近似的弹性波阻抗方程及反演 被引量:65
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作者 王保丽 印兴耀 张繁昌 《石油地球物理勘探》 EI CSCD 北大核心 2007年第4期435-439,共5页
为得到更准确的岩石物理参数数据体,减小计算误差的累积效应,人们希望通过某种方法直接提取岩石物理参数。用Connolly的弹性阻抗(EI)公式进行反演只能直接得到纵、横波速度和密度的信息,再通过计算得到相应的弹性参数,而且不同角度的弹... 为得到更准确的岩石物理参数数据体,减小计算误差的累积效应,人们希望通过某种方法直接提取岩石物理参数。用Connolly的弹性阻抗(EI)公式进行反演只能直接得到纵、横波速度和密度的信息,再通过计算得到相应的弹性参数,而且不同角度的弹性阻抗的量纲不统一。本文针对Connolly方法的不足,通过Gray近似把佐普里兹方程表示为反射系数是剪切模量μ、拉梅系数λ和密度ρ的函数,提出了以Gray的AVO近似方程为基础的一种新的弹性波阻抗反演公式,并对该公式进行了标准化以实现不同角度的弹性波阻抗间量纲的统一。文中用标准化后的弹性波阻抗反演公式对A地区的实际地震数据进行了反演,从反演得到的弹性阻抗数据体中可直接提取剪切模量μ、拉梅系数λ,表明用文中方法提取弹性参数更加稳定、准确。 展开更多
关键词 gray近似 弹性阻抗反演 标准化 拉梅参数
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广义Gray码及其在数字图像置乱中的应用 被引量:74
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作者 邹建成 李国富 齐东旭 《高校应用数学学报(A辑)》 CSCD 北大核心 2002年第3期363-370,共8页
以图像信息安全问题为背景 ,讨论了广义 Gray码及其在数字图像中的置乱作用 ,推广了丁玮等人 ( 1 999年 )的相关结果 .给出了图像置乱变换的周期 。
关键词 广义gray 数字图像 信息安全 置乱变换 周期性
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环F_p+vF_p上的v-常循环码及其Gray象 被引量:3
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作者 王敏 李捷 《大学数学》 2015年第6期87-91,共5页
定义了F_p+vF_p到F^2_p的Gray映射,其中v^2=1,证明了F_p+vF_p上长为n的v-常循环码在定义的Gray映射下的象是F_p上长为2n的距离不变的线性循环码,并进一步定义了F_p+vF_p上的广义Gray象,证明了其上线性码的广义Gray象是F_p上距离不变的... 定义了F_p+vF_p到F^2_p的Gray映射,其中v^2=1,证明了F_p+vF_p上长为n的v-常循环码在定义的Gray映射下的象是F_p上长为2n的距离不变的线性循环码,并进一步定义了F_p+vF_p上的广义Gray象,证明了其上线性码的广义Gray象是F_p上距离不变的线性码、循环码的广义Gray象是F_p上长为4n的4-准循环码. 展开更多
关键词 常循环码 准循环码 gray映射 广义gray映射
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紧致的Hilbert曲线Gray码索引算法 被引量:6
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作者 曹雪峰 万刚 张宗佩 《测绘学报》 EI CSCD 北大核心 2016年第B12期90-98,共9页
Hilbert曲线具有良好的聚簇性,使其成为设计全球立体网格多维数据索引的重要工具。但当数据集在不同维度上的分布密度存在较大差异时,常规Hilbert曲线索引会出现大量的冗余。对此,本文基于Gray码推导分析了Hilbert曲线索引的构造特点,... Hilbert曲线具有良好的聚簇性,使其成为设计全球立体网格多维数据索引的重要工具。但当数据集在不同维度上的分布密度存在较大差异时,常规Hilbert曲线索引会出现大量的冗余。对此,本文基于Gray码推导分析了Hilbert曲线索引的构造特点,进而设计实现了紧致Hilbert曲线索引算法,在保持Hilbert曲线良好聚簇性的同时,避免了数据维度分布差异带来的索引冗余问题。试验结果表明,相比常规Hilbert索引,紧致Hilbert曲线索引计算复杂度相当,在实例数据测试中编码耗时减少约40%,索引存储空间减少约46%,排序速度约为Hilbert排序的4.3倍。 展开更多
关键词 HILBERT曲线 gray 空间索引 全球离散网格
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改进的Gray World-Retinex图像自动白平衡方法 被引量:8
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作者 张钰 姚素英 +1 位作者 张娜 金则群 《数据采集与处理》 CSCD 北大核心 2008年第6期673-677,共5页
提出了一种改进的白平衡方法,改善了Gray World-Retinex算法对色彩丰富度低、近白(灰)点数量较少的图像白平衡后仍然偏色的缺点。使用图像Cb和Cr分量的样本标准差分析图像色彩丰富度,并改进了确定图像近白(灰)点数量的方法,最终定量地... 提出了一种改进的白平衡方法,改善了Gray World-Retinex算法对色彩丰富度低、近白(灰)点数量较少的图像白平衡后仍然偏色的缺点。使用图像Cb和Cr分量的样本标准差分析图像色彩丰富度,并改进了确定图像近白(灰)点数量的方法,最终定量地给出适合采用Gray World-Retinex白平衡法的图像特征,对于样本标准差极低而且近白(灰)点很少的图像,给出一种求极大值增益的方法进行白平衡。对40幅色彩丰富度和近白(灰)点数量不同的偏色图像进行验证,并与Gray World-Retinex算法作了对比。结果表明,本文算法对于具有不同色彩丰富程度和近白(灰)点数量的偏色图像,都可以获得较理想的白平衡效果。该算法复杂度低,对图像实时处理具有很大吸引力。 展开更多
关键词 自动白平衡 样本标准差 gray World—Retinex算法 CMOS图像传感器
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基于Gray码和线移条纹的结构光3D测量技术 被引量:11
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作者 于晓洋 吴海滨 《仪器仪表学报》 EI CAS CSCD 北大核心 2008年第4期701-704,共4页
结构光3D测量的关键问题之一是准确地确定图像采样点并求其投射角。提出一种以时序向被测表面投射Gray码和线移条纹进行编码,以亚像素定位技术提取Gray码条纹边缘和线移条纹中心,将其上点作为图像采样点进行解码的方法。消除了Gray码固... 结构光3D测量的关键问题之一是准确地确定图像采样点并求其投射角。提出一种以时序向被测表面投射Gray码和线移条纹进行编码,以亚像素定位技术提取Gray码条纹边缘和线移条纹中心,将其上点作为图像采样点进行解码的方法。消除了Gray码固有的一位解码误差对投射角求取的影响,同时提高了采样密度。文中具体介绍该方法的编码解码原理,分析了编码图案正交投射对测量准确度的影响,给出了仿真实验结果。测量误差约为0.04%。 展开更多
关键词 3D测量 结构光 gray 线移
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位平面与Gray码相结合的图像置乱方法 被引量:10
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作者 谭永杰 马苗 《计算机工程与应用》 CSCD 北大核心 2010年第16期174-177,共4页
针对数字图像的传输安全问题,提出一种将位平面分解与Gray码相结合的图像置乱方法。该方法首先将图像分解成8个位平面,通过位异或操作改变携带图像有用信息的高4位位平面的值,然后对得到的初步置乱图像的灰度值进行Gray码变换,进一步置... 针对数字图像的传输安全问题,提出一种将位平面分解与Gray码相结合的图像置乱方法。该方法首先将图像分解成8个位平面,通过位异或操作改变携带图像有用信息的高4位位平面的值,然后对得到的初步置乱图像的灰度值进行Gray码变换,进一步置乱图像,从而得到加密图像。初步实验结果显示,该方法置乱效果明显优于Arnold法、Hilbert法等现有置乱方法,且实现简单。 展开更多
关键词 图像置乱 位平面 gray
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广义GRAY码棒位测量研究 被引量:3
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作者 蒋跃元 王文然 +1 位作者 杨念祖 李德重 《核电子学与探测技术》 CAS CSCD 北大核心 1996年第3期197-201,共5页
在分析了控制棒棒位测量的特点后,本文提出了广义GRAY码的概念,此外,针对现役堆用棒位指示系统线圈太多、结构复杂的缺点研制了一种新型棒位测量系统——GRAY码棒位测量系统并进一步详细地介绍了该系统的编码原理。
关键词 控制棒 棒位测量 gray 芯棒
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环F_p+uF_p+…+u^kF_p上的线性码和常循环码的Gray像 被引量:4
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作者 朱士信 吴波 《合肥工业大学学报(自然科学版)》 CAS CSCD 北大核心 2006年第8期1049-1052,共4页
定义了环(Fp+uFp+…+ukFp)n到Fppkn的一个Gray映射;给出Gray映射的几个性质,证明环Fp+uFp+…+ukFp上的长为n的线性码的Gray像仍是线性码;及该环上长为n的(1-uk)-循环码的Gray像是域Fp上的长为pkn、指数为pk-1的准循环码。
关键词 gray映射 线性码 常循环码 准循环码
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