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In this dissertation, we develop the research work of the following three aspects based on existed work.First, using the scale-invariant property of multiscale model, i.e. Markovian among scales, a method of qth-order tree-based for multiscale representation of a class of 1-D stochastic process is presented. The multiscale stochastic model is established. The representation forms of parameter matrices, such as, the state transition matrix, the disturbance matrix, the initial state and the corresponding covariance matrix are deduced in detail. The multiscale sample paths based on distinctive order tree are presented by computer simulation.

本文在已有工作的基础上，开展了以下几个方面的研究工作： 1、根据多尺度模型尺度不变性，即利用尺度间的Markov性，给出了一类1-D随机过程基于一般q阶树的多尺度表示方法，建立了相应的多尺度动态模型，详细推导了多尺度模型中的状态转移阵、扰动阵、初始状态和相应的协方差阵，并通过计算机仿真给出了不同阶树的多尺度采样路径。

Firstly, the meaning of dynamic analysis on the steam turbine-generator set foundation is pointed out. Review and comment on the present research on dynamic analysis of domestic and international steam turbine-generator sets are presented Then a dynamic calculating model of the framed foundation of the steam turbine-generator set is set up based on finite element theory. Then dynamic analysis methods are put forward based on dynamics theory. The dynamic design of the foundation of the specific 12,000KW steam turbine-generator set is carried out.

论文首先指出汽轮发电机组基础动力分析的意义，并对国内外汽轮发电机组基础动力分析的研究现状进行了回顾及评述；其后，利用有限元原理建立了汽轮发电机组框架式基础的动力计算模型，根据动力学理论对该模型提出了自由振动分析和动力响应分析的方法，针对某工程12000KW汽轮发电机组的动力基础进行了动力设计。

This paper first analyses and summarizes the ststus quo and evolution trend of encryption, some common used cryptograph are introduced, including the algorithms used in symmetric cryptosystem and asymmetirc cryptosystem. We describe the theory of each algorithms and compare the elliptic curve cryptosystem with the other two asymmetric cryptosystems to show the advantages of this algorithm. Second, the principle of ECC is discussed, including the math foundation of ECC, basic conception of elliptic curves, constructiong idea of ECC, operation on the elliptic curve and so on. Third, the current attacks of ECC were analyzed deeply, and an algorithm based on limited prime number field was constructed. We analyzed its realizability in theory, and implement it by using certain function of MIRACL software package. Latter half in this paper, the implementation model of a simple elliptic curve encryption system which based on GF has been introduced. The paper also put a deep analysis on the algorithm of point addition and point multiplication.

本文首先对密码技术的发展现状及其发展趋势进行了分析和综述，详细的介绍了私钥密码系统和公钥密码系统的发展，说明各种算法的原理和优缺点，并给出了一些典型的密码体制的简要分析，重点将椭圆曲线算法与其它几种公钥密码算法比较，说明椭圆曲线算法的优势；其次，探讨了椭圆曲线密码体制的原理，包括椭圆曲线密码的数学基础、基本概念、椭圆曲线密码体制的构造思想等问题；第三作者对椭圆曲线的攻击现状作了详细的分析，针对所使用的大素数域F_p，设计了素数域上安全椭圆曲线产生的算法，从理论上做了可实施性分析，从软件上做了具体实现；在本文的后半部分，提出了一个简单的基于有限素数域上的椭圆曲线加密方按算实现模型，并对SECES中设计的点加和点乘运算进行了深入分析。

Moreover, solutions and strategies were proposed to solve the following crucial issues involved in conceptual process planning: product information identification based on key characteristics, multilevel resolution based manufacturing processes classification and selection, extensible core process planning, and producibility evaluation based on variation degree.

对概要工艺规划的关键技术，即基于关键特性的产品信息识别、具有多级分辨率的制造工艺分类与选择、具有可扩展性的核心工艺设计和基于差异度的可生产性评价，提出了解决方案。

As most of the present decision methods of propositional formulas are based on semantics and cannot give an important reference in many reasoning applications, namely deduction procedure, a deduction-based decision method that can give the deduction procedure during the decision procedure is presented based on the propositional calculus system L.

目前命题公式的判定方法大都是基于语义的，不能给出演绎过程，而演绎过程是许多推理性应用的重要依据。

In this paper,with respect to the ordinal variables,the definitions of attribute reduction of dominance-based rough set approach in ordered information systems and ordered decision tables are given.Then the approach of sorting objects comprehensively using rough set theory is brought in to obtain a series of ranks.Based on these ranks,nonparametric methods to analyze correlation between two attribute subsets are introduced,and Spearman rank correlation coefficient is used as a measure of attribute correlation.Based on this measure,a new method of attribute reduction of ordered information systems and ordered decision tables is presented without changing the ordinal information of the universe.

针对有序尺度变量，给出了有序信息系统与有序决策表在优势关系下的粗糙集约简定义；利用粗糙集方法将对象综合排序，进而得到一组秩；根据这些秩，运用非参数统计的思想研究了两个属性子集之间的相关性，并将Spearman秩相关系数作为属性相关性度量；在不改变总体序信息情况下，给出了基于此度量对有序信息系统与有序决策表进行约简的新方法。

So a novel content-based face image retrieval scheme is created based on this content feature-principle independent content feature. In this scheme, PICF based on higher order statistics is firstly extracted in the reduced space for effective representation of face images.

该方案首先在降维空间提取出基于高阶统计特性的主独立内容特征，应用提取的主独立内容特征进行有效的人脸图像描述。

Based on low satellites on orbit and STK platform, some parameters of space-based optical system such as observation direction, Right Ascension of the Ascending Node and True Anomaly are set and optimized in this paper, which will lay a foundation theoretically for the design of space-based optical system.

本文以在轨运行的低轨卫星为研究对象，以卫星工具包STK为平台对天基光学系统的观察方向、升交点赤经和真近点角等参数进行了优化设置，为天基光学系统的设计任务奠定理论基础。

However, Most vector-based algorithms of computing the Voronoi diagrams have difficulty while dealing with complex generators , and so author first discusses the properties of Voronoi diagram based on the Manhattan distance or supremum distance, the experimental result shows that Voronoi diagram based on the Manhattan distance or supremum distance or alternatively using these two distances is a rough approximation of Euclidean-metric Voronoi diagram.

鉴于构建Voronoi图的矢量方法存在一些问题及不足，首先分析了基于曼哈顿距离和上限距离的Voronoi图性质，进行了相应的实验，实验结果表明基于这两种距离或交替使用这两种距离所产生的Voronoi图与基于欧氏距离产生的Voronoi图之间存在较大的差异，属于精度较差的逼近方法。

Based on the traditional symbolic dynamic-based method, a novel algorithm based on a time-varying parameter of globally coupled map lattice is proposed.

本文在符号动力学方法的基础上，针对全局耦合映象模型，提出一种基于时变映象系数恢复信号初值的新方法。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。