We introduce in this paper cryptographic protocols which use combinatorial group theory. Based on a combinatorial distribution of shares we present secret sharing schemes and cryptosystems using Nielsen transformation...We introduce in this paper cryptographic protocols which use combinatorial group theory. Based on a combinatorial distribution of shares we present secret sharing schemes and cryptosystems using Nielsen transformations. Nielsen transformations are a linear technique to study free groups and general infinite groups. In addition the group of all automorphisms of a free group F, denoted by AUT (F), is generated by a regular Nielsen transformation between two basis of F, and each regular Nielsen transformation between two basis of F defines an automorphism of F.展开更多
为解决石油行业大数据高效安全传输难题,将图像转化为三通道矩阵数据并对矩阵进行奇异值分解,综合考虑Laplace算子、灰度方差函数、离散余弦变换系数、图像相关系数、熵函数、图像结构相似度和图像信噪比等7个评价因素,利用熵权逼近理...为解决石油行业大数据高效安全传输难题,将图像转化为三通道矩阵数据并对矩阵进行奇异值分解,综合考虑Laplace算子、灰度方差函数、离散余弦变换系数、图像相关系数、熵函数、图像结构相似度和图像信噪比等7个评价因素,利用熵权逼近理想解排序(technique for order preference by similarity to an ideal solution,TOPSIS)法对分解后的奇异值进行优选,在确保数据真实性的前提下用少量奇异值表征原始图像,进行图像压缩,降低数据大小,提高传输效率;提出多通道猫脸分割加密方法,分别对每个颜色通道的图像进行随机分割、随机加密和随机排序,解决了传统猫脸加密算法颜色通道线性相关度高,整体置乱度低的问题.结果表明:改进奇异值压缩技术在保证图像清晰的情况下仅利用15%的奇异值数据完成对图像的压缩,最大图像压缩比可达4.43,平均压缩后所占用的存储空间仅为原空间的26.29%,数据传输控制协议通信平均传输效率提高86.39%.在加密图像达到0相关的前提下,多通道猫脸分割加密算法加密图像在像素点处三通道颜色值完全不同,新方法颜色通道相关系数分别为0.20、0.22和0.25,对比传统猫脸加密方法,分别降低0.78、0.75和0.71.新方法加密效果好、难破解,可为石油行业数字化转型提供理论和技术支撑.展开更多
协议转换通常用于解决不同协议之间的数据交互问题,它的本质是寻找不同协议字段之间的映射关系。传统的协议转换方法存在以下缺点:转换大多是在特定协议的基础上设计的,因而这些转换是静态的,灵活性较差,不适用于多协议转换的场景;一旦...协议转换通常用于解决不同协议之间的数据交互问题,它的本质是寻找不同协议字段之间的映射关系。传统的协议转换方法存在以下缺点:转换大多是在特定协议的基础上设计的,因而这些转换是静态的,灵活性较差,不适用于多协议转换的场景;一旦协议发生改变,就需要再次分析协议的结构和字段语义以重新构建字段之间的映射关系,从而产生指数级的工作量,降低了协议转换的效率。因此,提出基于语义相似度的通用协议转换方法,旨在通过智能的方法发掘字段间的映射关系,进而提高协议转换的效率。首先,通过BERT(Bidirectional Encoder Representations from Transformers)模型分类协议字段,并排除“不应该”存在映射关系的字段;其次,通过计算字段之间的语义相似度,推理字段之间的映射关系,进而构建字段映射表;最后,提出基于语义相似度的通用协议转换框架,并定义相关协议以进行验证。仿真实验结果表明:所提方法的字段分类精准率达到了94.44%;映射关系识别精准率达到了90.70%,相较于基于知识抽取的方法提高了13.93%。以上结果验证了所提方法的有可行性,该方法可以快速识别不同协议字段之间的映射关系,适用于无人协同中多协议转换的场景。展开更多
Soybean is one of the world's most important oil and protein crops. Efficient transformation is a key factor for the improvement of soybean by genetic modification. We describe an optimized protocol for the Agroba...Soybean is one of the world's most important oil and protein crops. Efficient transformation is a key factor for the improvement of soybean by genetic modification. We describe an optimized protocol for the Agrobacterium rhizogenes-mediated transformation of soybean and the induction of hairy root development in vitro. Cotyledons with 0.5-cm hypocotyls were cut from 5-day-old seedlings and used as explants. After infection and co-cultivation,hairy roots were produced in induction culture medium after 10–12 days. Using this method, 90%–99% of the infected explants of five different cultivars produced hairy roots within one month. Observations using reporter constructs showed that 30%–60% of the hairy roots induced were transformed. Based on high transformation efficiency and short transformation period, this method represents an efficient and rapid platform for study of soybean gene function.展开更多
文摘We introduce in this paper cryptographic protocols which use combinatorial group theory. Based on a combinatorial distribution of shares we present secret sharing schemes and cryptosystems using Nielsen transformations. Nielsen transformations are a linear technique to study free groups and general infinite groups. In addition the group of all automorphisms of a free group F, denoted by AUT (F), is generated by a regular Nielsen transformation between two basis of F, and each regular Nielsen transformation between two basis of F defines an automorphism of F.
文摘为解决石油行业大数据高效安全传输难题,将图像转化为三通道矩阵数据并对矩阵进行奇异值分解,综合考虑Laplace算子、灰度方差函数、离散余弦变换系数、图像相关系数、熵函数、图像结构相似度和图像信噪比等7个评价因素,利用熵权逼近理想解排序(technique for order preference by similarity to an ideal solution,TOPSIS)法对分解后的奇异值进行优选,在确保数据真实性的前提下用少量奇异值表征原始图像,进行图像压缩,降低数据大小,提高传输效率;提出多通道猫脸分割加密方法,分别对每个颜色通道的图像进行随机分割、随机加密和随机排序,解决了传统猫脸加密算法颜色通道线性相关度高,整体置乱度低的问题.结果表明:改进奇异值压缩技术在保证图像清晰的情况下仅利用15%的奇异值数据完成对图像的压缩,最大图像压缩比可达4.43,平均压缩后所占用的存储空间仅为原空间的26.29%,数据传输控制协议通信平均传输效率提高86.39%.在加密图像达到0相关的前提下,多通道猫脸分割加密算法加密图像在像素点处三通道颜色值完全不同,新方法颜色通道相关系数分别为0.20、0.22和0.25,对比传统猫脸加密方法,分别降低0.78、0.75和0.71.新方法加密效果好、难破解,可为石油行业数字化转型提供理论和技术支撑.
文摘协议转换通常用于解决不同协议之间的数据交互问题,它的本质是寻找不同协议字段之间的映射关系。传统的协议转换方法存在以下缺点:转换大多是在特定协议的基础上设计的,因而这些转换是静态的,灵活性较差,不适用于多协议转换的场景;一旦协议发生改变,就需要再次分析协议的结构和字段语义以重新构建字段之间的映射关系,从而产生指数级的工作量,降低了协议转换的效率。因此,提出基于语义相似度的通用协议转换方法,旨在通过智能的方法发掘字段间的映射关系,进而提高协议转换的效率。首先,通过BERT(Bidirectional Encoder Representations from Transformers)模型分类协议字段,并排除“不应该”存在映射关系的字段;其次,通过计算字段之间的语义相似度,推理字段之间的映射关系,进而构建字段映射表;最后,提出基于语义相似度的通用协议转换框架,并定义相关协议以进行验证。仿真实验结果表明:所提方法的字段分类精准率达到了94.44%;映射关系识别精准率达到了90.70%,相较于基于知识抽取的方法提高了13.93%。以上结果验证了所提方法的有可行性,该方法可以快速识别不同协议字段之间的映射关系,适用于无人协同中多协议转换的场景。
基金supported by the Major Science and Technology Projects of China (2016ZX08010-004)the Ministry of Science and Technology of China (2016YFD0100504)the CAAS (Chinese Academy of Agriculture Sciences) Innovation Project
文摘Soybean is one of the world's most important oil and protein crops. Efficient transformation is a key factor for the improvement of soybean by genetic modification. We describe an optimized protocol for the Agrobacterium rhizogenes-mediated transformation of soybean and the induction of hairy root development in vitro. Cotyledons with 0.5-cm hypocotyls were cut from 5-day-old seedlings and used as explants. After infection and co-cultivation,hairy roots were produced in induction culture medium after 10–12 days. Using this method, 90%–99% of the infected explants of five different cultivars produced hairy roots within one month. Observations using reporter constructs showed that 30%–60% of the hairy roots induced were transformed. Based on high transformation efficiency and short transformation period, this method represents an efficient and rapid platform for study of soybean gene function.
