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A Novel Approach in Hydrogeochemical Exploration for Uranium Mineralization:an Example from West Central Sinai,Egypt 被引量:1
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作者 Ahmed E.EL-RAYES Mohamed O.ARNOUS 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2015年第6期1895-1913,共19页
Groundwater in contact with ore deposits may acquire a chemical composition that could be used as a guide for exploration. Eight well-water samples are collected from a known uraniummineralized area near Abu Zenima, w... Groundwater in contact with ore deposits may acquire a chemical composition that could be used as a guide for exploration. Eight well-water samples are collected from a known uraniummineralized area near Abu Zenima, west central Sinai to examine the applicability of using the hydrogeochemical technique in the search for uranium mineralization in similar arid areas. The analytical chemical data of the ground water is compared with ground radiometric measurements. The obtained results indicate that groundwater affected by uranium mineralization has a specific relativity of major anions expressed essentially as SO_4〉Cl〉HCO_3 and to a lesser extent as Cl〉SO_4〉HCO_3, associated as a rule with low magnesium content. This association constitutes a signature of uranium mineralization on the composition of groundwater in west central Sinai and could be used as an important exploration guide in the search for uranium deposits in similar areas. Anomalies in Ni, Fe, Zn and Cr and other pathfinder elements in groundwater can furnish geochemical guides to uranium ores. The immobile trace element anomalies, including Zn, Ni and Fe are strongly distributed near the orebody; whereas the relatively mobile trace elements, including Co, U, V and Cr, constitute the dispersion haloes away from the orebody. A new hydrogeochemical discrimination diagram is constructed to be used as a quick and cost effective exploration tool in the search for uranium occurrences in environmentally similar arid areas. Based on the obtained results, a new site for uranium occurrence, west of W. Baba, is delineated and recommended for future detailed geological and geochemical surveying. 展开更多
关键词 Hydrogeochemical exploration Uranium ores geospatial mapping graphical explorationtool remote sensing sinai
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基于一类二维混沌映射的数字图像置乱方法 被引量:4
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作者 张小红 黄剑 谢斐 《南昌大学学报(理科版)》 CAS 北大核心 2003年第4期399-402,共4页
利用混沌系统中的二维Sinai映射,将两组初始参数不同的混沌映射产生两队不同的伪随机的混沌时间序列,并利用混沌映射伪随机性非常好的特点,针对数字图像的特点进行随机空间置乱操作,并对保密性及算法的复杂性进行分析,程序用VC++6.0编... 利用混沌系统中的二维Sinai映射,将两组初始参数不同的混沌映射产生两队不同的伪随机的混沌时间序列,并利用混沌映射伪随机性非常好的特点,针对数字图像的特点进行随机空间置乱操作,并对保密性及算法的复杂性进行分析,程序用VC++6.0编写完成。 展开更多
关键词 二维混沌映射 数字图像 置乱 sinai映射 保密性 复杂性 多媒体通信 加密
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基于二维混沌映射的数字图像置乱方法 被引量:1
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作者 张小红 黄剑 谢斐 《华中科技大学学报(自然科学版)》 EI CAS CSCD 北大核心 2003年第S1期177-179,共3页
利用混沌系统中的二维Sinai映射 ,采用两组初始参数不同的混沌映射来产生两组不同的伪随机的混沌时间序列 ,基于混沌映射伪随机性优良特性 ,并针对数字图像的特点进行随机空间置乱操作实验 。
关键词 混沌 图像置乱 sinai映射
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基于语音信号和混沌序列的非对称图像隐藏方案 被引量:1
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作者 张小红 闵乐泉 《北京科技大学学报》 EI CAS CSCD 北大核心 2005年第6期754-759,共6页
基于广义混沌同步系统(GS)和广义离散Sinai映射,提出了具有非对称密钥的数字图像安全通讯方案.方案能通过一个常规的语音信号隐藏几乎所有计算机所能识别的图像文件,以实现信息的伪装与隐藏,且含有24个密钥数并能无损恢复隐藏图像... 基于广义混沌同步系统(GS)和广义离散Sinai映射,提出了具有非对称密钥的数字图像安全通讯方案.方案能通过一个常规的语音信号隐藏几乎所有计算机所能识别的图像文件,以实现信息的伪装与隐藏,且含有24个密钥数并能无损恢复隐藏图像,密钥空间可达到10^(360).该方案能使接收方利用非对称密钥对收到的密文进行数据源真伪性认证和解密,适用于网络数字通讯语音伪装中的图像传输.对密钥空间、密钥参数敏感性和加密图像的相关性等分析表明该方案具有较高的安全性. 展开更多
关键词 广义混沌同步 sinai映射 图像处理 语音伪装 图像加密 数据源认证
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A Non-symmetric Digital Image Secure Communication Scheme Based on Generalized Chaos Synchronization System
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作者 ZHANG Xiao-Hong MIN Le-Quan 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第6X期1115-1124,共10页
Based on a generalized chaos synchronization system and a discrete Sinai map, a non-symmetric true color(RGB) digital image secur e communication scheme is proposed. The scheme first changes an ordinary RGB digital im... Based on a generalized chaos synchronization system and a discrete Sinai map, a non-symmetric true color(RGB) digital image secur e communication scheme is proposed. The scheme first changes an ordinary RGB digital image with 8 bits into unrecognizable disorder codes and then transforms the disorder codes into an RGB digital image with 16 bits for transmitting. A receiver uses a non-symmetric key to verify the authentication of the received data origin,and decrypts the ciphertext. The scheme can encrypt and decrypt most formatted digital RGB images recognized by computers, and recover the plaintext almost without any errors. The scheme is suitable to be applied in network image communications. The analysis of the key space, sensitivity of key parameters, and correlation of encrypted images imply that this scheme has sound security. 展开更多
关键词 广义混沌同步 图像混乱 数据原点鉴别 网络通讯
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基于混沌复合映射的数字图像加解密仿真研究
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作者 戴晶平 《电脑开发与应用》 2005年第5期55-57,共3页
利用连续Lorenz方程与离散的Sinai映射复合产生的序列,将常规的8位真彩图像和索引图像RGB三色置乱,该设计方案能对计算机所能识别的几乎所有图像格式进行快速加密和完整还原,同时从密钥参数、统计特性、运行速度分析了系统的保密性,实... 利用连续Lorenz方程与离散的Sinai映射复合产生的序列,将常规的8位真彩图像和索引图像RGB三色置乱,该设计方案能对计算机所能识别的几乎所有图像格式进行快速加密和完整还原,同时从密钥参数、统计特性、运行速度分析了系统的保密性,实验仿真结果用Matlab实现。 展开更多
关键词 计算机仿真 加密 解密 数字图像 混沌复合映射 LORENZ方程 sinai映射
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