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基于中心投影形状特征的车载移动测量系统交通标志自动识别

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仪器仪表学报 2010年第9期31卷 2101-2108页

作者：张卡盛业华叶春李志英南京师范大学虚拟地理环境教育部重点实验室南京210046

针对车载移动测量系统所拍摄图像中的交通标志的自动识别问题,提出了一种基于中心投影特征的交通标志自动识别算法。文中详细研究了基于自适应图像分割和中心投影变换的交通标志图像的形状特征计算方法,利用信息熵解决了中心投影变换的... 详细信息

针对车载移动测量系统所拍摄图像中的交通标志的自动识别问题,提出了一种基于中心投影特征的交通标志自动识别算法。文中详细研究了基于自适应图像分割和中心投影变换的交通标志图像的形状特征计算方法,利用信息熵解决了中心投影变换的最佳投影个数确定问题。在中心投影特征计算的基础上,利用训练后的概率神经网络实现了交通标志具体含义的自动识别。使用车载移动测量系统所拍摄的实际交通标志图像对本文算法进行了实验,并将中心投影形状特征和不变矩特征及SIFT特征的识别效果进行了对比,实验结果表明基于中心投影特征的识别方法具有最高的识别准确率。

关键词：道路交通标志识别车载移动测量系统中心投影变换形状特征概率神经网络

甘蓝型油菜REVEILLE家族鉴定及诱导表达分析

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生物技术通报 2024年第6期40卷 161-171页

作者：刘蓉田闵玉李光泽谭成方阮颖刘春林作物代谢调控与代谢工程实验室、湖南农业大学农学院长沙410128 作物表观遗传调控与发育湖南省重点实验室、湖南农业大学生物科技学院长沙410128

【目的】REVEILLE家族基因具有重要生物学功能,而在甘蓝型油菜(Brassica napus L.)中该家族基因研究较少,深入认识甘蓝型油菜中RVE家族基因功能及其与非生物胁迫的关系。【方法】利用生物信息学方法,在甘蓝型油菜、白菜(Brassica rapa)... 详细信息

【目的】REVEILLE家族基因具有重要生物学功能,而在甘蓝型油菜(Brassica napus L.)中该家族基因研究较少,深入认识甘蓝型油菜中RVE家族基因功能及其与非生物胁迫的关系。【方法】利用生物信息学方法,在甘蓝型油菜、白菜(Brassica rapa)和甘蓝(***)中分别鉴定到33、16和16个RVE基因,并对其系统进化、染色体定位、基因结构和理化性质以及启动子顺式元件进行分析。【结果】所有的RVE蛋白被分为两个亚家族。33个BnaRVE分别定位在18条A亚基因组的染色体和15条C亚基因组的染色体上。大部分成员属于较稳定的疏水蛋白;多数ka/Ks值小于1,说明该家族受到强烈的纯化选择作用。基因结构变异较大,内含子数目在4-11之间。共线性分析结果表明,甘蓝型油菜和拟南芥、白菜、甘蓝存在大量的同源基因。大部分甘蓝型油菜RVE家族成员在子叶和叶都有表达且表达量最多。BnaRVE启动子上含有大量与激素和生物逆境相关的元件,通过定量PCR分析,4个BnaRVE在ABA与MeJA诱导和低温胁迫下的表达量显著上调。【结论】在甘蓝型油菜基因组中鉴定出33个BnaRVE家族成员。不同基因在不同发育时期和不同组织中表现出不同的表达模式。不同基因对各种胁迫存在响应,且表达模式不一。RVE家族成员对ABA、MeJA和冷胁迫具有正向响应功能。

关键词：甘蓝型油菜 RVE基因家族生物信息学分析逆境植物激素表达分析表达谱

Double-authentication-preventing signatures revisited:new definition and construction from chameleon hash

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Frontiers of Information Technology & Electronic Engineering 2019年第2期20卷 176-186页

作者： Fei LI Wei GAO Gui-lin WANG Ke-fei CHEN chun-ming TANG School of Mathematics and Statistics Ludong University Key Laboratory of Information Security Guangzhou University China-USA Computer Science Research Center Nanjing University of Information Science and Technology Shield Lab Singapore Research Center of Huawei Department of Mathematics Hangzhou Normal University

Double-authentication-preventing signature(DAPS) is a novel signature notion proposed at ESORICS2014. The double-authentication-preventing property means that any pair of signatures on two different messages with the same subject will result in an immediate collapse of the signature system. A few potential applications of DAPS have been discussed by its inventors, such as providing a kind of self-enforcement to discourage certificate authority(CA) from misbehaving in public key infrastructure and offering CA some cryptographic arguments to resist legal coercion. In this study, we focus on some fundamental issues on DAPS. We propose a new definition,which is slightly weakened but still reasonable and strong enough to capture the DAPS concept. We develop the new notion of invertible chameleon hash functions with key exposure. Then we propose a generic DAPS scheme, which is provably secure if the underlying invertible chameleon hash function with key exposure is secure. We instantiate this general construction to obtain the DAPS schemes respectively based on the well-known assumptions of integer factorization, Rivest-Shamir-Adleman(RSA), and computational Diffie-Hellman(CDH). They are more efficient than previous DAPS schemes. Furthermore, unlike previous constructions, the trusted setup condition is not needed by our DAPS schemes based on RSA and CDH.

关键词： Double-authentication-preventing signatures Chameleon hash function Digital signature Provable security Authority trust level

Low-cost Sm0.7Y0.3Co5 sintered magnet produced by traditional powder metallurgical techniques

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Rare Metals 2020年第4期39卷 421-428页

作者： Dong-Tao Zhang Nai-Xing Cai Rong-chun Zhu Wei-Qiang Liu Ming Yue College of Materials Science and Engineering Key Laboratory of Advanced Functional MaterialsMinistry of Education of ChinaBeijing University of TechnologyBeijing 100124China

RCo5(R=rare earth)sintered magnets have good temperature stability,so it is still widely used in high temperature *** this paper,by the method of adding liquid phase SmCo1.7 to the main phase,Sm0.7Y0.3Co5 magnet was prepared by traditional powder metallurgical *** results show the presence of a main phase RCo5,a minor phase R2 Co7,and a R-rich phase in the *** the results of the XRD(X-ray diffraction)in random and oriented directions,the magnet has a well-aligned(00l)orientated texture,which is consistent with the result of the electron backscattered diffraction(EBSD).The Sm0.7Y0.3Co5 sintered magnet has good magnetic properties as remanence(Br)is 0.96 T,the coercivity(Hcj)is 1201.96 ka·m-1,and maximum magnetic energy product((BH)max)is 175.16 kJ m-3.

关键词： Sm0.7Y0.3Co5 Sintered magnets Low-cost Magnetic properties RCo5

HYPOPIGMENTATION AND HEALTHY SKIN PROMOTING EFFECT OF A MODIFIED QI BAI SAN

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World Journal of Traditional Chinese Medicine 2016年第2期 81-82页

作者： Elaine Wat Yau Tsz Chan Tiffany Hoi ka Tso chun Fai Ng Ching Po Lau Wing Sum Siu chun Hay Ko ka Keung Lau Raymond Hu Clara Bik-San Lau Ping chung Leung Institute of Chinese Medicine and State Key Laboratory of Phytochemistry and Plant Resources in West China The Chinese University of Hong Kong 5100 Cosmetic Company Ltd.

Introduction:Qi Bai San(QBS,七白散)is a traditional Chinese herbal formula used by ancient ladies for healthy skin and *** it is a popular product in the market,it contains animal drug and toxic herbs which

关键词： MSH HYPOPIGMENTATION AND HEALTHY SKIN PROMOTING EFFECT OF A MODIFIED QI BAI SAN

Early-onset primary torsional dystonia in a 4-generation Chinese family with a mutation in the DYT1 gene

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Chinese Medical Journal 2005年第10期118卷 873-876页

作者： YEUNG Wai Lan LAM Ching Wan CHENG Wai Tsoi SIN Ngai Chuen WONG Wing Kin WONG chun Nei TSE ka Ming FOK Tai Fai Departments of Paediatrics Prince of Wales HospitalThe Chinese University of Hong KongHong KongChina Chemical Patholog Prince of Wales HospitalThe Chinese University of Hong KongHong KongChina Department of Paediatrics and Adolescent Medicine Queen Mary HospitalUniversity of Hong Kong Nuclear Medicine&PET Division Scanning DepartmentSt.Teresa’s HospitalHong KongChina

Primary torsion dystonia(PTD)is a clinically and genetically heterogeneous movement *** least thirteen different types of dystonia can be distinguished on a genetic basis.~1 The DYT1 gene was first mapped by Ozelius et al in 1989.~2(Kramer et)al^3 linked the same locus to PTD in 12 Ashkenazi Jewish families in *** patients with early-onset generalized PTD were caused by the same three base pair(GAG)deletion in the DYT1 gene on chromosome 9q34.^(1,4,5)The product of the gene is a protein called torsinA.~5(Although the)function of this protein is as yet uncertain,it is widely distributed throughout the brain with high levels in the substantia nigra compacta dopamine neurones.

关键词： DYT1 gene dystonia positron emission tomography

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卫星影像定位方位元素相关性影响仿真

中国矿业大学学报 2009年第4期38卷 488-493页

作者：程春泉邓喀中张继贤张力中国矿业大学环测与测绘学院江苏徐州221116 中国测绘科学研究院摄影测量与遥感研究所北京100039

以地心直角系下航天遥感影像严密定位模型为基础,运用模拟和仿真的手段,研究在不同成像条件下,遥感影像外方位元素存在误差时,导致的定位误差经修正其相关性元素进行补偿后残差存在的规律,并通过图形表示出来.该方法为不同条件下遥感影... 详细信息

以地心直角系下航天遥感影像严密定位模型为基础,运用模拟和仿真的手段,研究在不同成像条件下,遥感影像外方位元素存在误差时,导致的定位误差经修正其相关性元素进行补偿后残差存在的规律,并通过图形表示出来.该方法为不同条件下遥感影像的纠正、定位、区域网平差、方位元素相关性和去相关性研究提供一种新的误差定量分析工具,通过仿真得出的方位元素相关性补偿残差分布图,能为这些研究提供直观的理论指导.

关键词：相关性误差分析仿真摄影测量严密模型

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基于灰度投影的数字近景摄影立体影像匹配

光学学报 2005年第12期25卷 1623-1628页

作者：盛业华张卡叶春牛芩涛韩冰南京师范大学地理信息科学江苏省重点实验室南京210097

根据数字近景摄影测量的特点,针对建筑物三维建模的需要,提出了基于灰度投影的影像匹配算法。该算法将影像行、列两个方向上的一维灰度投影,拓展为行、列、主对角线和次对角线四个方向上的一维灰度投影,计算左右影像的四个一维投影向量... 详细信息

根据数字近景摄影测量的特点,针对建筑物三维建模的需要,提出了基于灰度投影的影像匹配算法。该算法将影像行、列两个方向上的一维灰度投影,拓展为行、列、主对角线和次对角线四个方向上的一维灰度投影,计算左右影像的四个一维投影向量间的相似性测度的加权平均值作为最后的匹配测度。利用相对定向线性变换(RLT)算法来确定同名核线,以改进的动态定界法来控制待匹配点序列中后续点沿核线匹配的搜索范围,以减少匹配的搜索空间并提高匹配的准确度。利用该算法对建筑物数字近景摄影影像进行了实验,结果表明该算法具有较高的匹配速度和匹配准确率。

关键词：光学测量遥感近景摄影测量影像匹配灰度投影相对定向线性变换算法

Non-vesicle-bound free microRNAs could enter cells and affect gene expression

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Advances in Bioscience and Biotechnology 2012年第3期3卷 181-185页

作者： Gang Wang ka-Bik Lai Bonnie Ching-Ha Kwa kai-Ming Chow Philip kam-Tao Li Cheuk-chun Szeto Department of Medicine & Therapeutics The Chinese University of Hong Kong Hong Kong China

Background: Cell-free microRNAs (miRNAs) exist in body fluid. Previous studies showed that cell-free mi-RNAs are partly bound in microvesicles, and could transfer between cells via fusion with cell membrane. Methods: We quantified the amount of a panel of mi-RNA targets in and outside microvesicles in human proximal tubular epithelial cell (HK2) medium by microarray and real-time quantitative polymerase chain reaction (RT-QPCR). Intercellular miRNA transfer was explored by medium transfer experiments. Results: We identified a portion of cell-free miRNAs that exists as non-vesicle bound, truly naked form. More importantly, these non-vesicle bound free miRNA could transfer between cells and exert biological effects. By miRNA microarray, we showed that the expression of many miRNA targets in HK-2 cells were altered, either up- or down-regulated, after exposure to extrinsic free miRNAs. The miRNA-200 family was the most affected in our model, with a corresponding alteration in the messenger RNA expression of down-stream targets including ZEB1 and vimentin. Conclusion: Our results suggest that free miRNA may serve as an intercellular messenger, a phenomenon that needs further exploration.

关键词： Cell Signaling Fibrosis Cytokine