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31.
A common computing-core representation of the discrete cosine transform and discrete sine transform is derived and a reduced-complexity algorithm is developed for computation of the proposed computing-core. A parallel architecture based on the principle of distributed arithmetic is designed further for the computation of these transforms using the common-core algorithm. The proposed scheme not only leads to a systolic-like regular and modular hardware for computing these transforms, but also offers significant improvement in area-time efficiency over the existing structures. The structure proposed here is devoid of complicated input/output mapping and does not involve any complex control. Unlike the convolution-based structures, it does not restrict the transform length to be a prime or multiple of prime and can be utilized as a reusable core for cost-effective, memory-efficient, high-throughput implementation of either of these transforms 相似文献
32.
Analysis and architecture design of variable block-size motion estimation for H.264/AVC 总被引:1,自引:0,他引:1
Ching-Yeh Chen Shao-Yi Chien Yu-Wen Huang Tung-Chien Chen Tu-Chih Wang Liang-Gee Chen 《IEEE transactions on circuits and systems. I, Regular papers》2006,53(3):578-593
Variable block-size motion estimation (VBSME) has become an important video coding technique, but it increases the difficulty of hardware design. In this paper, we use inter-/intra-level classification and various data flows to analyze the impact of supporting VBSME in different hardware architectures. Furthermore, we propose two hardware architectures that can support traditional fixed block-size motion estimation as well as VBSME with less chip area overhead compared to previous approaches. By broadcasting reference pixel rows and propagating partial sums of absolute differences (SADs), the first design has the fewer reference pixel registers and a shorter critical path. The second design utilizes a two-dimensional distortion array and one adder tree with the reference buffer that can maximize the data reuse between successive searching candidates. The first design is suitable for low resolution or a small search range, and the second design has advantages of supporting a high degree of parallelism and VBSME. Finally, we propose an eight-parallel SAD tree with a shared reference buffer for H.264/AVC integer motion estimation (IME). Its processing ability is eight times of the single SAD tree, but the reference buffer size is only doubled. Moreover, the most critical issue of H.264 IME, which is huge memory bandwidth, is overcome. We are able to save 99.9% off-chip memory bandwidth and 99.22% on-chip memory bandwidth. We demonstrate a 720-p, 30-fps solution at 108 MHz with 330.2k gate count and 208k bits on-chip memory. 相似文献
33.
R. Urata R. Takahashi T. Nakahara K. Takahata H. Suzuki 《Photonics Technology Letters, IEEE》2006,18(1):67-69
We propose an optically clocked transistor array optoelectronic integrated circuit (OEIC) for both serial-to-parallel and parallel-to-serial conversion (demux/mux), enabling an interface between high-speed asynchronous burst optical labels and CMOS circuitry for optical label swapping. Dual functionality of the OEIC reduces size, power, and cost of the optical label swapper. The capability for greater than 20-Gb/s conversion operation is demonstrated. 相似文献
34.
对许多企业而言,不仅需要能够简单部署的安全远程访问解决方案,而且还需要能够紧密地与企业已投资的身份管理系统进行集成的解决方案。为了满足安全远程访问的实时需求,SafeNet最近推出了无边界安全企业级访问服务器(Borderless SecurityEnterprise Access Server)。该产品不仅具备SSL VPN功能,而且利用特殊配置及设定来满足大型企业的严苛要求(快速建立安全存取控制解决方案,并提供迅速的ROI)。该产品安装在稳固且高效能的1U装置中,将IPSec及SSL VPN、稳固的用户认证、多方授权、端点安全兼容检查以及广泛的认证功能整合在一起,… 相似文献
35.
基于ISO/IEC17799标准建立了一个综合的信息系统风险分析框架,并运用模糊多准则决策(FMCDM)方法计算信息安全风险,根据风险等级矩阵(RLM)对信息资产风险进行级别划分,最终建立评估信息资产相关风险的完整模型。 相似文献
36.
37.
A cell vertex finite volume method for the solution of steady compressible turbulent flow problems on unstructured hybrid
meshes of tetrahedra, prisms, pyramids and hexahedra is described. These hybrid meshes are constructed by firstly discretising
the computational domain using tetrahedral elements and then by merging certain tetrahedra. A one equation turbulence model
is employed and the solution of the steady flow equations is obtained by explicit relaxation. The solution process is accelerated
by the addition of a multigrid method, in which the coarse meshes are generated by agglomeration, and by parallelisation.
The approach is shown to be effective for the simulation of a number of 3D flows of current practical interest.
Sponsored by The Research Council of Norway, project number 125676/410
Dedicated to the memory of Prof. Mike Crisfield, a respected colleague 相似文献
38.
The catalytic activities of alumina prepared from an Al alkoxide-amine adduct monomer for the reaction of cyclopentene oxide with piperidine was determined after various pretreatments, including calcination and exposure to moisture. They were compared with the activity of alumina prepared by the conventional hydrolysis method. It was found that the as-prepared sample from the alkoxide-amine monomer preparation was five times more active than a conventional preparation, suggesting that it has a higher density of surface Lewis acid sites. However, its activity was much more severely suppressed by exposure to moisture. 相似文献
39.
A decision support system for interactive decision making - Part II: analysis and output interpretation 总被引:2,自引:0,他引:2
Liping Fang K.W. Hipel D.M. Kilgour Xiaoyong Peng 《IEEE transactions on systems, man and cybernetics. Part C, Applications and reviews》2003,33(1):56-66
For pt.I see ibid., p.42-55 (2003). The development of a comprehensive decision support system, GMCR II, for the systematic study of real-world interactive decision problems is presented. The companion paper (Part I), discusses how GMCR II elicits, stores, and manages conflict models; here (Part II), the focus is on GMCR IIs analysis and output interpretation subsystems. Specifically, this paper describes the powerful and efficient analysis engine contained in GMCR II, its informative output presentation and interpretation facilities, and a number of follow-up analyses. Furthermore, an illustrative case study is used to demonstrate how GMCR II can be conveniently applied in practice. 相似文献
40.
微制造平台微振动的最优控制 总被引:6,自引:0,他引:6
采用混合隔振技术建立了微制造平台隔振系统。该系统以空气弹簧和橡胶层作为被动隔振元件、超磁致伸缩致动器作为主动隔振元件,并采用最优控制理论设计其主动控制器。研究了在不同的性能指标加权阵的情况下,该主动振动控制系统对基础干扰和由微制造设备产生的直接干扰所引起的微制造平台振动的控制效果。研究表明性能指标加权阵对振动控制效果影响非常大。通过大量的仿真实验确定了一组性能指标加权阵,使所设计的主动控制系统能在较宽的频率范围对基础干扰和直接干扰所引起的微制造平台振动进行有效的控制。 相似文献