查询词典 cryptographic

Second, in the viewpoint of crypto analysis, the practical requirement for the cryptographic function is to construct the function that can resist all the known crypto analysis and attacks. In advanced, the main cryptographic properties are compared, and the relation among these cryptographic properties is analyzed, including the trade-off ones. Get the conclusion that the construction of cryptographic Boolean function is to find out the proper Boolean function in the whole vector space under the restriction of several cryptographic properties required for the security system.

然后本文从密码分析的角度，讨论了密码函数的实际需求，即构造能够抵抗已有密码分析与攻击的布尔函数；分析了布尔函数的主要的密码学性质，并比较了这些性质之间的相互关系，包括制约的关系；得出了构造布尔函数的实质的结论，即在向量空间中构造全体布尔函数，以所需的若干密码学性质作为限制条件，用有限域上的多项式、Walsh谱、Hadamard矩阵等数学工具找出适当的布尔函数用于加密体制的设计。

In many fields related to information security, people use Hardware Cryptographic System, such as cryptographic processor、 cryptographic accelerator、smartcard or USB key, to provide high speed data operation and to improve the security of the whole system.

在很多涉及信息安全的系统中，人们采用了诸如高速数据密码卡、密码机、智能卡、USB KEY等硬件密码设备来提高密码运算速度和系统的安全性。

It is a new study direction of cryptograph that detecting potential flaws in cryptographic protocols using formal analysis of cryptographic protocol.

在通信网络中，身份认证是第一道安全屏障，也是实施访问控制的基础，通信安全几乎总是开始于身份认证握手过程。

Random Sequence is very important in cryptographic technology, just as the famous cryptograph ! st Bruce Schneier said: within the six elements of Cryptographic Technology, the generation of Random Sequence is seldom discussed, but it is also important as others.

随机序列在密码技术中是很重要的，正如著名的密码学家Bruce Schneier所说：在密码技术的六个要素中，随机序列的生成是谈论最少的加密要素，不过它也和其它要素一样重要。

In this thesis we study existing cryptographic tools and then use them to design more complex cryptographic systems.

在这论文中，我们研究基本的密码学工具，并使用它们来设计复杂的应用系统。

We provide a substitution box, exponential permutation which has much measurable security, and give a enumerating result and a fast algorithm of calculating such permutation. An almost perfect nonlinear exponential permutation with high algebric degree is proposed. with some discussion on how to select the parameters of such permutation. The experimental result shows us a conjecture that there exists no such permutation over even dimensional space. As a way of generating substitution boxes, we briefly point out the cryptographic weakness of the exponential functions derived from such permutation. We also present two new cryptographic indexes, fixed point and cyclic structure, on which we investigate the performance of such permutation. Finally, we give a viewpoint about the application of correlation immune functions in designing substitution boxes.

提供了一种可度量安全强度的代换盒－幂置换；详细阐述了幂置换的实现和计数问题；给出了一种计算幂置换的快速算法；从几乎完善非线性幂置换角度讨论了幂置换参数的选取，并提出了一种高次几乎完善非线性置换；通过试验给出了关于偶数维空间上几乎完善非线性幂置换的一个猜想；简要给出了由幂置换派生出的幂函数的密码局限性；针对幂置换，提出了两个密码安全指标：不动点和循环结构；证明了幂置换在这两个指标下的密码性能；简要讨论了相关免疫函数与代换盒设计的关系。

The main contributions of the second part of this dissertation are focused on the cryptographic properties of logical functions over finite field, with the help of the properties of trace functions, and that of p-polynomials, as well as the permutation theory over finite field: The new definition of Chrestenson linear spectrum is given and the relation between the new Chrestenson linear spectrum and the Chrestenson cyclic spectrum is presented, followed by the inverse formula of logical function over finite field; The distribution for linear structures of the logical functions over finite field is discussed and the complete construction of logical functions taking on all vectors as linear structures is suggested, which leads to the conception of the extended affine functions over finite field, whose cryptographic properties is similar to that of the affine functions over field GF (2) and prime field F〓; The relationship between the degeneration of logical functions and the linear structures, the degeneration of logical functions and the support of Chrestenson spectrum, as well as the relation between the nonlinearity and the linear structures are discussed; Using the relation of the logical functions over finite field and the vector logical functions over its prime field, we reveal the relationship between the perfect nonlinear functions over finite field and the vector generalized Bent functions over its prime field; The existence or not of the perfect nonlinear functions with any variables over any finite fields is offered, and some methods are proposed to construct the perfect nonlinear functions by using the balanced p-polynomials over finite field.

重新定义了有限域上逻辑函数的Chrestenson线性谱，考察了新定义的Chrestenson线性谱和原来的Chrestenson循环谱的关系，并利用一组对偶基给出了有限域上逻辑函数的反演公式；给出了有限域上随机变量联合分布的分解式，并利用随机变量联合分布的分解式对有限域上逻辑函数的密码性质进行了研究；给出了有限域上逻辑函数与相应素域上向量逻辑函数的关系，探讨了它们之间密码性质的联系，如平衡性，相关免疫性，扩散性，线性结构以及非线性度等；讨论了有限域上逻辑函数各类线性结构之间的关系，并给出了任意点都是线性结构的逻辑函数的全部构造，由此引出了有限域上的"泛仿射函数"的概念；考察了有限域上逻辑函数的退化性与线性结构的关系、退化性与Chrestenson谱支集的关系；给出了有限域逻辑函数非线性度的定义，利用有限域上逻辑函数的非线性度与相应素域上向量逻辑函数非线性度的关系，考察了有限域上逻辑函数的非线性度与线性结构的关系；利用有限域上逻辑函数与相应素域上向量逻辑函数的关系，揭示了有限域上的广义Bent函数与相应素域上的广义Bent函数的关系，以及有限域上的完全非线性函数与相应素域上向量广义Bent函数之间的关系；给出了任意有限域上任意n元完全非线性函数存在性与否的完整证明，并利用有限域上平衡的p-多项式的性质给出了有限域上完全非线性函数的一些基本构造方法。

For evaluating the security of cryptographic device in the risk environment full of electromagnetic analysis adversaries,by enhancing the adversary's ability in the classical cryptographic black box model, two novel adversaries,the key recover adversary and the indistinguishability determined adversary who takes the advantage of electromagnetic emissions,were defined within the framework of physical observable cryptography model.

为在充斥电磁分析旁路攻击敌手的危险环境下评估密码设备的安全性，通过将密码学标准黑盒模型中的敌手能力进行加强，在物理可观测密码术模型的框架内，定义了具有电磁泄漏信息分析能力的密钥恢复敌手与不可分辫性判定敌手。

In the end, by introducing the newest advances in both foreign and domestic cryptographic researches, this course also help students to feel the modern cryptographic algorithms on its impendency in current practical applications and its tendency in future development.

最后，通过对国内外密码学最新进展的介绍，使学生切实感受现代密码算法在实际应用中的迫切性以及今后发展的趋势。

Affine inverse function s derived from the inverse function composed with affine permutations possess good cryptographic properties.

有限域上的逆函数左右复合一个仿射置换而成的仿射逆函数具有很好的密码学性质。

The dissecting of samples in group2 were difficult. The root of pulmonary artery and ascending aorta failed to be unfolded because fibrous tissue was tough, right and left fibrous trigone were too firm to be solved by hand. Cardiac muscle fibers couldn't be stripped along myofibrillar trajectory since they were prone to break because of their friability.

组2的心脏解剖困难，表现为纤维组织坚韧，游离肺动脉非常困难；徒手无法松解左、右纤维三角，肺动脉和主动脉根部的游离非常困难；心肌纤维坚硬、质脆，解剖时容易断离成碎块，无法沿纤维走行方向剥离。

We have battled against the odds in a province that has become increasingly violent.

我们对在一个争夺日益激烈省的可能性。