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991.
992.
TAN Zuowen 《武汉大学学报:自然科学英文版》2008,13(6):680-684
A group-oriented (t, n) threshold signature scheme employs the cryptographic techniques of secret share, allows any subset of t players out of n players to sign message on behalf of the group and disallows the creation of a valid signature if fewer than t players take part in the signature protocol. In this paper, we proposed a new group-oriented (t, n) threshold signature schemes with traceable signers based on Schnorr signature. The proposed scheme is proved traceable, robust and unforgeable against the "static" adversary with the discrete logarithm assumption in the random oracle model and existence of broadcast channel. The proofs of the strongest security (existential unforgeability against adaptively chosen message attacks under the discrete logarithm assumption) are provided in the random oracle model. 相似文献
993.
994.
995.
Traditional approach of design by contract, due to mixing the contract code with application code, is difficult for the extensibility
and reusability of software system. This paper presents a framework named JADBC for design by contract based on Aspect-Oriented
Programming (AOP) to resolve these problems. By providing a new modularized element, aspect, the framework successfully separates
the contracts in design by contract, from functional codes. The implementation of this framework is based on dynamic AOP which
can have the contract changed at runtime, consequently, enhancing program flexibility. JADBC framework modularizes the contracts
in a clear-cut fashion that is easier to design, implement, and maintain.
Biography: WEN Jing (1982–), female, Ph.D. candidate, research directions: software engineer, aspect-oriented software development. 相似文献
996.
CHEN Lihua 《武汉大学学报:自然科学英文版》2008,13(1):9-13
The singularly perturbed initial boundary value problems for the reaction diffusion system are raised. Firstly, under suitable conditions, using a iteration technique, the differential inequalities theorem is constructed and introducing two auxiliary functions the existence and uniqueness theorem of solution for the basic reaction diffusion system is proved. Using the singularly perturbed method the formal asymptotic expressions of the solution are constructed with power series theory. By using the comparison theorem the existence and its asymptotic behavior of solution for the original problem are studied. Finally, using method of estimate inequalities, the structure of solutions for the problem is discussed thoroughly in three cases and asymptotic solution of the original problem is given. The asymptotic behavior of solution in the three cases is proved. 相似文献
997.
文章主要完成两方面的工作:将特征匹配和极线几何估计有机的结合起来,给出一种基于组合优化的特征点匹配方法;以往两视角关系的校正方法是根据图像的亮度信息,对相邻两幅图像对应的亮度误差最小化,而图像的亮度信息会受到拍摄时的角度、光线及噪声的影响.文章提出一种基于边缘信息的校正方案对RANSAC算法进行改进.实验结果表明,利用边缘信息完全脱离了拍摄光线的影响,该方法很好的降低了噪声的影响. 相似文献
998.
OPTIMAL MAINTENANCE AND REPLACEMENT OF EXTRACTION MACHINERY 总被引:1,自引:1,他引:0
This paper considers a problem of optimal preventive maintenance and replacement schedule of equipment devoted to extracting resources from known deposits. Typical examples are oil drills, mine shovels, etc. At most one replacement of the existing machinery by a new one is allowed. The problem is formulated as an optimal control problem subject to the state constraint that the remaining deposit at any given time is nonnegative. We show that the optimal preventive maintenance, production rates, and the replacement and salvage times of the existing machinery and the new one, if required, can be obtained by solving sequentially a series of free-end-point optimal control problems. Moreover, an algorithm based on this result is developed and used to solve two illustrative examples. 相似文献
999.
GENG Nian XUE Ni RU Guobao 《武汉大学学报:自然科学英文版》2008,13(1):67-70
A new blind equalization algorithm based on the modified constant modulus algorithm (MCMA) and dithered signederror constant modulus algorithm (DSE-CMA) is proposed. This dithered signed-error MCMA (DSE-MCMA) can not only reduce the computational complexity, but also recover the phase rotation in the complex channel. Simulation results have verified the analysis and indicated the good property of DSE-MCMA. 相似文献
1000.
对载人航天安全性评价时,需要处理两类不同的数据,即随机性数据和可能性数据。本文根据载人航天过程,初步建立了功能的对象模型,在此基础上,基于模糊规划方法,将两类安全性数据进行了统一处理,并提出了载人航天系统安全性模糊评价的求解方法。 相似文献