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关于N(2,2,0)代数的平移类 被引量:1
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作者 李旭东 《西北师范大学学报(自然科学版)》 CAS 2002年第2期19-22,共4页
作为可约化半群的推广,引入了半群左(右)可约化的概念,进一步讨论了N(2,2,0)代数的平移变换的性质,并讨论了某些平移类的代数结构.
关键词 N(2 2 0)代数 可约化半群 平移变换 同态 正则元 代数结构 平移类
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G(~ef)中序列的周期及平移等价类定理的证明
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作者 刘祥伟 吴永 罗中函 《重庆工学院学报》 2005年第8期76-78,共3页
阐述了线性移位寄存器序列的定义及其相关概念、证明定理所需的引理,给出了定理的内容.以不可约多项式f(x)的幂链的构造为基础,给出了G(fe)中序列的周期及平移等价类定理的完整证明过程.
关键词 线性移位寄存器序列 多项式的周期 平移等价 不可约多项式f(x)的幂链
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m—阵列的平移等价类
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作者 胡磊 《广州师院学报(自然科学版)》 1996年第2期47-50,共4页
本文研究线性递归m—阵列的平移等价类。
关键词 m-阵列 平移等价 周期 线性复杂度 数字通信 周期向量 Z-模
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一种基于Mean-Shift聚类算法的图像区域分割方法 被引量:2
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作者 尹美林 周咏梅 《计算机应用与软件》 CSCD 2009年第7期94-97,159,共5页
提出一种基于均值平移(Mean-Shift)聚类算法的图像区域分割方法。该方法首先选用适当的彩色空间对图像中的每个像素点抽取颜色、纹理及空间位置等特征,形成特征空间;然后,利用Mean-Shift聚类算法,在像素点特征空间中进行聚类,利用提出... 提出一种基于均值平移(Mean-Shift)聚类算法的图像区域分割方法。该方法首先选用适当的彩色空间对图像中的每个像素点抽取颜色、纹理及空间位置等特征,形成特征空间;然后,利用Mean-Shift聚类算法,在像素点特征空间中进行聚类,利用提出的方法,确定最佳窗口半径参数,进而确定聚类簇数、聚类中心等参数,将像素初步划归不同的组,并利用相邻像素之间的连接原理对图像区域进一步分割。分割方法提供了丰富的区域描述特征。实验结果表明这种方法具有图像分割速度快,分割效果好等特点。 展开更多
关键词 均值平移 图像区域分割 区域描述
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一类非自治时滞抛物方程的一致吸引子
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作者 王圆 黄建华 《数学杂志》 CSCD 北大核心 2010年第3期537-545,共9页
本文研究了一类具有平移有界非自治外力的时滞抛物方程的动力学性态,得到了其整体解的存在和唯一性.利用时间符号理论,并通过构造乘积空间中的紧吸收集,在时间符号空间非紧的情形下得到了一致吸引子的存在性.
关键词 一致吸引子 平移有界函数 非自治抛物方程 时滞
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Classification of Teleparallel Homothetic Vector Fields in Cylindrically Symmetric Static Space-Times in Teleparallel Theory of Gravitation
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作者 Ghulam Shabbir Suhail Khan 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第10期675-678,共4页
In this paper we classify cylindrically symmetric static space-times according to their teleparallel homothetic vector fields using direct integration technique. It turns out that the dimensions of the teleparallel ho... In this paper we classify cylindrically symmetric static space-times according to their teleparallel homothetic vector fields using direct integration technique. It turns out that the dimensions of the teleparallel homothetic vector fields are 4, 5, 7 or 11, which are the same in numbers as in general relativity. In case of 4, 5 or 7 proper teleparallel homothetic vector fields exist for the special choice to the space-times. In the case of 11 teleparallel homothetic vector fields the space-time becomes Minkowski with all the zero torsion components. Teleparallel homothetic vector fields in this case are exactly the same as in general relativity. It is important to note that this classification also covers the plane symmetric static space-times. 展开更多
关键词 teleparallel homothetic vector fields WeitzenbSck connections TORSION
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Two types of coaxial self-balancing robots 被引量:1
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作者 高学山 戴福全 李潮全 《Journal of Central South University》 SCIE EI CAS 2013年第11期2981-2990,共10页
Two types of coaxial self-balancing robots(CSBR)were proposed,one can be used as a mobile robot platform for parts transporting in unmanned factory or as an inspector in dangerous areas,and the other can be used as a ... Two types of coaxial self-balancing robots(CSBR)were proposed,one can be used as a mobile robot platform for parts transporting in unmanned factory or as an inspector in dangerous areas,and the other can be used as a personal transporter ridden in cities.Mechanical designing and control structures as well as control strategies were described and compared in order to get a general way to develop such robots.A state feedback controller and a fuzzy controller were designed for the robot using DC servo motors and the robot using torque motors,respectively.The experiments indicate that the robots can realize various desired operations smoothly and agilely at the velocity of 0.6 m/s with an operator of 65 kg.Furthermore,the robustness of the controllers is revealed since these controllers can stabilize the robot even with unknown external disturbances. 展开更多
关键词 mobile robots service robots mechatronic systems robot dynamics control of robotic systems
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Classification of Kantowski-Sachs and Bianchi Type Ⅲ Space-Times According to Their Killing Vector Fields in Teleparallel Theory of Gravitation
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作者 Ghulam Shabbir Suhail Khan 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第9期469-472,共4页
In this paper we classify Kantowski-Sachs and Bianchi type Ⅲ space-times according to their teleparallel Killing vector fields using direct integration technique. It turns out that the dimension of the telepaxallel K... In this paper we classify Kantowski-Sachs and Bianchi type Ⅲ space-times according to their teleparallel Killing vector fields using direct integration technique. It turns out that the dimension of the telepaxallel Killing vector fields are 4 or 6, which are the same in numbers as in general relativity. In case of 4 the teleparallel Killing vector fields are multiple of the corresponding Killing vector fields in general relativity by some function of t. In the case of 6 Killing vector fields the metric functions become constants and the Killing vector fields in this case are exactly the same as in general relativity. Here we also discuss the Lie algebra in each case. 展开更多
关键词 teleparallel killing vector fields Weitzenb5ck connections TORSION
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Trend in Coral-Algal Phase Shift in the Mandapam Group of Islands, Gulf of Mannar Marine Biosphere Reserve, India
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作者 M. Machendiranathan L. Senthilnathan +4 位作者 R. Ranith A. Saravanakumar T. Thangaradjou S. B. Choudhrys S. K. Sasama 《Journal of Ocean University of China》 SCIE CAS 2016年第6期1080-1086,共7页
The present study revealed proliferation of macro-algae modifying coral reef ecosystems in a different manner due to diseases and sedimentations in the Mandapam group of islands in the Gulf of Mannar. Benthic surveys ... The present study revealed proliferation of macro-algae modifying coral reef ecosystems in a different manner due to diseases and sedimentations in the Mandapam group of islands in the Gulf of Mannar. Benthic surveys were conducted with major attack of seven coral reefs diseases with high sedimentation rate, nine species of fleshy macro-algae(Turbinaria ornata, Turbinaria conaides, Caulerpa scalpelliformis, Caulerpa racemosa, Kappaphycus alvarezii, Padina gymnosphora, Sargassum wightii, Ulva reticulata and Calurpa lentillifera) proliferation against major corals life forms(Acropora branching, Acropora digitate, Acropora tabulate, coral massive, coral submassive, coral foliose and coral encrusting). The results confirm that diseased corals most favor to macro-algae growth(15.27%) rather than the sedimentation covered corals(8.24 %). In the degradation of coral life forms, massive corals were more highly damaged(7.05%) than any other forms. Within a short period of time(May to September), coral coverage shrank to 17.4% from 21.9%, macro-algae increased 23.51% and the average sedimentation rate attained 77.52 mg cm^(-2) d^(-1) with persisting coral reef diseases of 17.59%. The Pearson correlation showed that the coral cover decreased with increasing macro-algae growth, which was statistically significant(r =-0.774, n = 100, P < 0.0005). The proliferation of the various macro-algae C. scalpellifrmis, T. ornata, C. racemosa, T. conaides, U. reticulata, S. wightii, K. alvarezii, P. gymnosphora and C. lentillifera increased with percentages of 6.0, 5.8, 5.7, 4.9, 4.2, 3.7, 2.7 and 1.9, respectively. If this trend continues, the next generation of new recruit corals will undoubtedly lead to a phase shift in Gulf of Mannar corals. 展开更多
关键词 climate change SEDIMENTATION disease proliferation recovery MACROALGAE Mandapam Gulf of Mannar
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Expression of proto-oncogene Fra-1 in human neoplastic breast tissues
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作者 Yuhua Song Jing Wang +2 位作者 Xiaoyun Yu Santai Song Zefei Jiang 《The Chinese-German Journal of Clinical Oncology》 CAS 2012年第6期332-335,共4页
Objective: Invasion and metastasis are the most significant and intrinsic biological characteristics of cancers, also which are main factors of malignant tumor causing treatment failure and death. Recent studies have... Objective: Invasion and metastasis are the most significant and intrinsic biological characteristics of cancers, also which are main factors of malignant tumor causing treatment failure and death. Recent studies have found that Fra-1 plays an important role on cell migration, invasion, and maintaining malignant phenotype of transformed cells. But there are few stud- ies about the expression and location of Fra-1 in breast tissues and cells being reported .This study just aims to discuss the expression and location of transcription factor Fra-1 in benign and malignant human breast tissues. Methods: The expression of Fra-1 was investigated by immunohistochemistry in neoplastic breast diseases ranging from benign fibroadenoma to very aggressive undifferentiated carcinoma. The correlations of Fra-1 expression with other indicators of breast carcinoma prog- nosis (ER, PR and ErbB2 receptors) were analyzed. Results: All neoplastic breast tissues, either benign or malignant breast tissues, were nuclear immunoreactive for Fra-l-recognizing antibody. In 85% of benign tumors (17/20), the immunoreactive for Fra-l-recognizing antibody as exclusively restricted to the nuclei. In three cases (3/20, 15%), focal unequivocal cytoplas- mic staining was also exhibited. Strong positive nuclear staining for Fra-1 was easily seen in all types of breast carcinomas. However the nucleaflcytoplasmic concomitant immunoreactivity was observed in all types of breast carcinomas. A clear shift in Fra-1 immunoreactivity, from an exclusively nuclear to a simultaneous nuclear and cytoplasmic localization was noticed in 90.2% (37/41) of breast carcinomas. No inverse relationship between Fra-1 and ER and PR protein levels was noticed in malignant tumors. The relative expression level of Fra-1 was not correlated with the expression of ErbB2. Conclusion: The overall expression, pattern and intensity of Fra-1 proteins were correlated with breast oncogenesis. Overexpression of Fra-1, leading to a persistent high cytoplasmic accumulation, may play a role in the process of breast carcinogenesis. 展开更多
关键词 breast cancer Fra-1 transcription factor irnmunohistochernistry
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一类Smale空间上的C~*-代数自同构的熵
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作者 侯成军 《数学学报(中文版)》 CSCD 北大核心 2017年第1期149-158,共10页
Ian Putnam利用Smale空间上的渐近等价关系定义了广群C~*-代数及其典则自同构.本文在零维Smale空间的情形下,计算此类C~*-自同构的逼近熵,证明了相应C~*-动力系统关于CNT熵和逼近熵的"变分原理"成立.由此推演出此类Smale空间... Ian Putnam利用Smale空间上的渐近等价关系定义了广群C~*-代数及其典则自同构.本文在零维Smale空间的情形下,计算此类C~*-自同构的逼近熵,证明了相应C~*-动力系统关于CNT熵和逼近熵的"变分原理"成立.由此推演出此类Smale空间上的Bowen测度诱导的C~*-代数上的态是此典则自同构的唯一平衡态. 展开更多
关键词 拓扑熵 广群C*-代数 有限平移 变分原理
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Lipschitz区域上一类非自治时滞抛物方程的吸引子
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作者 王圆 黄建华 《应用数学学报》 CSCD 北大核心 2010年第6期1049-1060,共12页
本文研究了Ljpschitz区域上的一类非自治时滞抛物方程,得到其整体解的存在唯一性,并通过构造乘积空间中的紧吸收集,在时间符号空间非紧的情形下证明了一致吸引子的存在性.
关键词 一致吸引子 LIPSCHITZ区域 平移有界函数 非自治抛物方程 时滞
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VERTICAL HEREDITY VS. HORIZONTAL GENE TRANSFER: A CHALLENGE TO BACTERIAL CLASSIFICATION 被引量:3
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作者 HAO Bailin(Institute of Theoretical Physics, Academy of Chinese Sciences, Beijing 100080, China Senior International Fellow of the Santa Fe Institute T-Life Research Center, Fudan University,Shanghai 200433, China)QI Ji(Institute of Theoretical Physics, Beijing 100080, China) 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2003年第3期307-314,共8页
The diversity and classification of microbes has been a long-standing issue.Molecular phylogeny of the prokaryotes based on comparison of the 16S rRNA sequences of the small ribosomal subunit has led to a reasonable t... The diversity and classification of microbes has been a long-standing issue.Molecular phylogeny of the prokaryotes based on comparison of the 16S rRNA sequences of the small ribosomal subunit has led to a reasonable tree of life in the late 1970s. How-ever, the availability of more and more complete bacterial genomes has brought about complications instead of refinement of the tree. In particular, it turns out that different choice of genes may tell different history. This might be caused by possible horizontal gene transfer (HGT) among species. There is an urgent need to develop phylogenetic methods that make use of whole genome data. We describe a new approach in molecular phylogeny,namely, tree construction based on K-tuple frequency analysis of the genomic sequences.Putting aside the technicalities, we emphasize the transition from randomness to determin-ism when the string length K increases and try to comment on the challenge mentioned in the title. 展开更多
关键词 prokaryote phylogeny horizontal gene transfer FITNESS compositionaldistance
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通信枢纽楼能耗运行分析研究 被引量:1
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作者 樊春锋 伍建萍 《电信工程技术与标准化》 2016年第5期89-92,共4页
如何在业务量不断增加,电源容量无法扩容的情况下,更好地解决供电能力紧张、机房装机位不足、机房散热等问题,是本论文的研究意义所在。本文通过对S省通信枢纽楼能耗运行分析,给出以上难点的合理化建议和建设指导原则。
关键词 枢纽楼 变压器 能耗 红色预警 搬迁
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