Research Advance on Rockburst Theory and Its Engineering Application in Collieries

This paper summarizes and describes the progress in coal rockmass outburst theory in resent decades both at home and abroad,discusses the tendency of mechanism of rockburst,and gives a fullier review about the presently adopted prediction methods and preventive measures,simultaneously looks into the prospective development on the study of prediction and preventive measures and its practical applications.     

Chen＇s混沌系统的同步控制

主要对非线性复杂动力系统——Chen＇s系统的同步控制作出了研究,主要利用驱动-响应同步原理,设计了4种不同的非线性反馈控制器来控制2个初始条件不同的Chen＇s系统达到同步。     

public-key Encryption Based on Torus Automorphisms

Chaotic maps with its characteristic are very useful in cryptography, however, compared with wide application in symmetric system, the research about chaos in public-key encryption system is still few. Through analysing the period of toms automorphisms which is a prototype of chaotic map, and making use of the framework of the traditional public-key algorithm RSA, the authors propose a chaotic public-key encryption algorithm based on toms automorphisms. Its security is based on the intractability of the integer factorization problem as RSA, and it is able to resist the chosen-ciphertext attack against RSA and easy to be implemented.     

An algorithm of image processing based on discrete wavelet transform compression and chaotic scrambling

An algorithm was proposed in view of the combination of image compression and encryption. We got the approximate part and three detail parts after transforming the image with discrete wavelet transform (DWT), and compressed the image by modifying the detail parts by a given threshold value based on human visual systems. And then, we encrypted the image by scrambling the approximate part because this part held mostly of the energy. Last, a compressed and encrypted image can be achieved after DWT. Simulation result shows a good effect on the combination of compression and encryption.     

基于混合混沌信息加密的农业信息传输的设计与分析

文章研究了在农业信息传输过程中确保信息安全的重要性,根据混沌密码研究的现状提出一种新的复合混沌密钥设计,使其能在保留原混沌性质的基础上复杂性、有效性能进一步提高,更好的满足信息加密的需要.对加密模型模块进行设计、仿真、测试,对输出序列进行分析,从理论设计及实验分析上讨论由该模块产生的混沌序列的输出特性,使该设计能在实际中得到更好的应用     

灌溉用水量混沌演变特性分析

运用混沌理论分析灌溉用水量的演变趋势,通过灌溉用水量序列相空间重构在高维空间中恢复演变规律,考虑时间延迟与嵌入维数的相关性,利用C-C法计算相空间重构参数,通过最大Lyapunov指数来判别系统混沌特性。进行了实例研究,通过不同方法相互补充和验证,结果都说明了灌溉用水量演变存在混沌特性,为灌溉用水量的混沌预测和控制奠定了基础。     

植物茎干水分系统混沌动力学特性分析

植物水分系统由于与周围环境的非线性相互作用,通常表现出复杂的时空格局。为了探究植物水分系统中的混沌特性,该研究以相空间重构、相关维数（correlation dimension,CD）、最大李雅普诺夫指数（largest Lyapunov exponent,LLE）为基础,研究了植物茎干水分时间序列中可能存在的混沌行为,研究树种包括海棠、花楸、黄丁香、铅笔柏和杨树。结果表明,植物水分系统存在混沌现象,且植物水分动态特性由控制变量数量有限的确定性系统决定。不同种类植物的茎干水分混沌参数普遍存在差异,同种植物生长状态相近时茎干水分的混沌参数相近,当生长状态出现差异时混沌参数随之发生变化。对不同生长状态的植物茎干水分混沌参数分析发现,杨树在干旱胁迫下LLE不高于0.006,而对照组平均值为0.010,木质部破坏胁迫后LLE不高于0.007,而对照组平均值为0.019,表明混沌参数可有效表征植物茎干水分数据变化趋势,并与植物生长状态存在联系,可以尝试利用这一规律对植物生长状态进行预测与回溯。该研究尝试从混沌理论的角度分析植物水分系统的复杂性,可为理解植物水分动力学的混沌行为提供新的途径。