A pairing-free identity-based authenticated key agreement protocol with minimal message exchanges

Based on the computational Diffie-Hellman problem, this paper proposes an identity-based authenticated key agreement protocol which removes bilinear pairings. Compared with previous protocols, the new protocol minimizes message exchange time with no extra cost. The protocol provides strong security guarantees including key compromise impersonation resilience, perfect forward secrecy, and master key forward secrecy. A security proof with the modular approach in the modified Bellare-Rogaway model is also provided.     

多元智能理论在任职教育中的应用初探

多元智能理论强调人类智能在性质与结构上的多元性。针对新形势下军队任职教育的特点与需求,以提高岗位任职能力和创新实践能力为目标,考虑学员在个体需求和智能结构上的差异,探讨了任职教育在教学方法、教学环境和资源保障需求与应对策略,分析了相应的教学评估手段。     

Master‐slave synchronization for delayed Lur'e systems using time‐delay feedback control

This paper deals with the problem of designing delayed feedback controllers of master‐slave synchronization for Lur'e systems with time‐variant delay (0≤τ₀≤τ(t)≤τ_m). Through partitioning the intervals [0, τ₀] and [τ₀, τ_m], respectively, and choosing two augmented Lyapunov‐Krasovskii functionals(LKFs), two delay‐dependent synchronization criteria are formulated in the form of linear matrix inequalities (LMIs), in which the conservatism can be greatly reduced by thinning the partitioning of delay intervals and employing convex combination. Thus the sufficient conditions can be derived for the existence of delayed feedback controllers, and the controller gain matrices can be achieved by solving the established LMIs. Finally, three numerical examples are given to illustrate the presented synchronization schemes. Copyright © 2010 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society     

Classical and variational multiscale LES of the flow around a circular cylinder on unstructured grids

The effects of numerical viscosity, subgrid scale (SGS) viscosity and grid resolution are investigated in LES and VMS-LES simulations of the flow around a circular cylinder at Re=3900 on unstructured grids. The separation between the largest and the smallest resolved scales in the VMS formulation is obtained through a variational projection operator and finite-volume cell agglomeration. Three different non-dynamic eddy-viscosity SGS models are used both in classical and in VMS-LES. The so-called small-small formulation is used in VMS-LES, i.e. the SGS viscosity is computed as a function of the smallest resolved scales. Two different grid resolutions are considered. It is found that, for each considered SGS model, the amount of SGS viscosity introduced in the VMS-LES formulation is significantly lower than in classical LES. This, together with the fact that in the VMS formulation the SGS viscosity only acts on the smallest resolved scales, has a strong impact on the results. However, a significant sensitivity of the results to the considered SGS model remains also in the VMS-LES formulation. Moreover, passing from classical LES to VMS-LES does not systematically lead to an improvement of the quality of the numerical predictions.     

基于OpenCV的改进两步法摄像机标定

采用改进两步法实现了摄像机的标定,并给出基于OpenCV算法,充分发挥了OpenCV的函数库功能。对两步标定法的改进是在原两步法得到摄像机参数值的基础上,用非线性优化算法对所有参数进一步优化,得到最终参数值,既提高了摄像机标定精度和计算效率,又无需对摄像机像面中心预标定,简化了标定过程。     

高职院校非计算机专业计算机课教学方法浅议

计算机技术已成为21世纪高素质、具有国际竞争力人才必备的技能和素质。该文对目前高职院校中非计算机专业的学生的计算机基础应用能力的状况进行分析。介绍了在计算机文化基础课程的理论教学中,学习兴趣的培养、教学内容的选择、教学方法的采用以及在实验教学中应注意的方面。对计算机基础教学改革提出设想,引入“项目教学法”,不断促进高职计算机基础教育的发展。     

离散数学课程教学改革探索与实践

离散数学是计算机科学的核心基础理论课,该课程不但为学生学好后续课程提供数学理论基础,而且学好该课程有利于培养学生的数学思维。本文结合教学实践,分析了当前离散数学教学中存在的问题,针对该课程的特点,从教学内容、教学手段和教学方法3个方面对离散数学的教学改革进行了探讨,力求使该课程的教学上一个新的台阶。     

机制主义方法与人工智能统一理论——人工智能的新方法与新进展

报导人工智能研究的一项重要进展:由于发现了人工智能研究的"机制主义"模拟方法和"知识的生态学结构",使原来"鼎足三分"的3个主流学说(结构模拟、功能模拟和行为模拟学说)在"机制主义方法"的基础上实现了和谐的统一,形成了统一理论,从而为人工智能的发展提供了新的基础。     

计算机类课程小班教学模式研究

本文阐述了计算机类课程开展小班教学的基本理念,提出小班教学具体实施原则。针对推广小班教学面临的各种障碍,结合国内高校计算机教学实际情况,提出了若干建设性意见与措施方法。