一种基于FPGA的实时NPR系统

在进行非真实感渲染(NPR)处理时需要大量的计算,这对高帧率、高分辨率的视频做实时的NPR渲染是一个难题。根据FPGA以并行运算为主的特点,对传统的NPR算法做了改进和简化,最终设计了一种基于FPGA的实时NPR系统。实验结果表明,该系统对高帧率、高分辨率的视频做实时NPR处理具有运算速度快、系统稳定等特点,同时还具有体积小、便于携带等优点。     

一种改进的分层路网的路径规划算法应用

为了提高路径规划效率,提出一种改进的分层路网的路径规划算法。首先,城市路网进行分层处理,以经典A*算法为核心,在高层路网上使用改进机制,评估函数做相应调整,然后,对其权值设置上下限阈值,提高算法的搜索精度及搜索效率。实验结果表明,规划的路径并非Dijkstra算法的最短,但是改进的算法使快速路段所占比例达90%以上,实际运行最优。     

基于Hyperworks的平衡轴支架拓扑优化设计

拓扑优化是一种根据载荷、约束及优化目标寻求结构材料最佳分配的优化方法,既可用于全新产品的概念设计,又可用于已有产品的改进设计;基于Hyperworks平台采用变密度法进行重卡平衡轴支架的拓扑优化设计,对优化后的重卡平衡轴支架进行有限元分析,将其应力分布、质量与原设计做比较;研究表明,经拓扑优化后的重卡平衡轴悬轴支架,应力大小大幅度减少,应力分布更加均匀,质量大幅度减少,实现了轻量化,为平衡轴支架结构的改进设计提供了重要的技术信息。     

The ring authenticated encryption scheme – How to provide a clue wisely

Though cryptography is being used more and more widely in reality, it seems that there exists no scheme or a concatenation of some existing schemes that could deal soundly with such practical situations as providing a clue, where the provider of the clue may want to reserve his beneficial rights while keeping his identity secret. To address this problem, inspired by the two notions of the ring signature and the authenticated encryption signature, we propose a new type of authenticated encryption scheme, which we call the ring authenticated encryption scheme, which can enable any member of a group of persons to provide a clue to some designated recipient wisely.     

一种统一的资源预留策略

资源预留可以保证任务在开始执行时获得资源,而这在网格这样资源动态性很强的环境中是很可贵的,因而资源预留是网格任务调度中一种普遍采用的策略。当前资源预留的研究主要集中在计算资源预留的情况,文中提出了一个网格环境中资源预留的统一策略,该策略对其它资源的预留和计算资源的预留一起加以考虑,经过模拟验证,该策略能够很好地和我们先前设计的一种基于资源预留的任务映射算法结合起来,适用于网格的动态、异构性环境。     

A Hybrid Learning Method for the Data-Driven Design of Linguistic Dynamic Systems

In lots of data based prediction or modeling applications, uncertainties and/or noises in the observed data cannot be avoided. In such cases, it is more preferable and reasonable to provide linguistic (fuzzy) predicted results described by fuzzy memberships or fuzzy sets instead of the crisp estimates depicted by numbers. Linguistic dynamic system (LDS) provides a powerful tool for yielding linguistic (fuzzy) results. However, it is still difficult to construct LDS models from observed data. To solve this issue, this paper first presents a simplified LDS whose inputoutput mapping can be determined by closed-form formulas. Then, a hybrid learning method is proposed to construct the data-driven LDS model. The proposed hybrid learning method firstly generates fuzzy rules by the subtractive clustering method, then carries out further optimization of centers of the consequent triangular fuzzy sets in the fuzzy rules, and finally adopts multiobjective optimization algorithm to determine the left and right end-points of the consequent triangular fuzzy sets. The proposed approach is successfully applied to three real-world prediction applications which are: prediction of energy consumption of a building, forecasting of the traffic flow, and prediction of the wind speed. Simulation results show that the uncertainties in the data can be effectively captured by the linguistic (fuzzy) estimates. It can also be extended to some other prediction or modeling problems, in which observed data have high levels of uncertainties.      

一种隐藏访问结构的文件层次属性加密研究

基于文件层次结构的属性加密方案在云存储环境下是高效率、低存储的,但访问结构本身包含敏感信息,存在用户信息泄露、文件易被窃取的风险,针对这一问题提出了一种隐藏访问结构的文件层次属性加密方案。该方案在不影响加密解密效率的前提下提高了加密算法的安全性,并采用双因子身份认证机制实现了更安全高效的访问控制。该研究成果基于判定性双线性Diffie-Hellman假设,在标准模型下被证明是安全的。     

一种基于TTL的主动队列管理算法

文章提出了一种新颖的主动队列管理算法TRED——基于TTL(TimetoLive)的ECN及BECN的综合。ECN和BECN在指示拥塞的过程中各有优缺点,二者的综合可望提高拥塞指示的效率。TTL是在网络上传输的分组必需的属性,且每一次转发都要经过检测,以决定该分组的处理方式——转发或丢弃。通过对TTL的判断来决定网络拥塞指示的方式——ECN或BECN。该机制可利用ECN及BECN的优势,同时不会对反向链路造成很大的压力。仿真结果显示算法在队列长度以及吞吐量方面都取得了不错的效果。     

Multimedia cloud transmission and storage system based on internet of things

For the issues of large space and storage security of multimedia files, we analyzed the impact of access control and cloud storage on multimedia file, and proposed a mixed security cloud storage framework based on Internet of Things. This paper introduced the concept of multimedia protection into the method based on role access control. Moreover, we also adopted a scheme based on the combination of multimedia data state and role access control. At the same time, all input and output devices were connected to this system. Internet of Things is used to judge whether circuits are connected and whether the devices are normally operated, so as to improve the access efficiency. On this basis, we also described in detail the complete process of registration, role assignment, multimedia file owner’s request for data encryption, and user login and access to multimedia file. According to the result, this scheme can be used to resist the known attacks. It guarantees security of multimedia files.