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71.
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A fast intra skip detection algorithm based on the rate‐distortion (RD) cost for an inter frame (P‐slices) is proposed for H.264/AVC video encoding. In the H.264/AVC coding standard, a robust rate‐distortion optimization technique is used to select the best coding mode and reference frame for each macroblock (MB). There are three types of intra predictions according to profiles. These are 16×16 and 4×4 intra predictions for luminance and an 8×8 intra prediction for chroma. For the high profile, an 8×8 intra prediction has been added for luminance. The 4×4 prediction mode has 9 prediction directions with 4 directions for 16×16 and 8×8 luma, and 8×8 chrominance. In addition to the inter mode search procedure, an intra mode search causes a significant increase in the complexity and computational load for an inter frame. To reduce the computational load of the intra mode search at the inter frame, the RD costs of the neighborhood MBs for the current MB are used and we propose an adaptive thresholding scheme for the intra skip extraction. We verified the performance of the proposed scheme through comparative analysis of experimental results using joint model reference software. The overall encoding time was reduced up to 32% for the IPPP sequence type and 35% for the IBBPBBP sequence type. 相似文献
73.
采用低界面张力的正丁醇-丁二酸-水体系,在塔径为0.1m的新型规整填料(FG型)萃取塔中,研究了两相流体力学和相间传质特性。试验结果表明,这种塔型具有较高的传质效率和较大的通量。将它用于糖醛精制转盘萃取塔的技术改造获得成功,取得了显著的经济效益。 相似文献
74.
介绍了一种利用8098单片机的HSIO口直接实现多路可控硅调功调压的新方法,其特点是调整精度高,方法简单;导通角范围为1~179°,占空比为0.5%~99.5%,最大触发功率为5W. 相似文献
75.
Qinliang Su Aiping Huang Jing Li Hsiao‐Hwa Chen 《International Journal of Communication Systems》2009,22(11):1427-1443
In this paper, we propose an approach to reduce the multi‐user detection (MUD) complexity based on user grouping and signal replica classification by exploiting the correlation characteristics of spreading sequences in multipath fading channels. The spreading sequences are constructed from inter‐group complementary codes with a sparse and regular correlation matrix and inherit its attractive auto/cross‐correlation properties. Users are first partitioned into independent user groups according to whether or not there is interference among them, and then the replicas of user signals from the same user group are further classified into independent replica classes. The MUD is carried out within each low‐dimensional user group or replica class, respectively, reducing the MUD complexity substantially. This approach can be applied to most of the existing MUD algorithms for complexity reduction, and in this paper optimal MUD and multi‐stage MUD are exemplified. The analytical and simulated results demonstrate that this approach can reduce the MUD complexity significantly under any load conditions without performance loss. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
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77.
提出了一种适用于数字音视频编解码标准(AVS)的视频解码帧间运动矢量预测的解码方法,根据AVS宏块模式的特点,以统一的基本运算单元处理所有的解码模式,模块化流水计算,降低了硬件实现的复杂度。采用ASIC结构并使用Verilog语言进行设计、模拟,并成功通过了现场可编程门阵列验证。模块的每个功能块均为专用的VLSI结构,通过系统控制器控制各部分的运行,能有效地提高时钟频率,减小芯片的面积。使用0.18μmCMOS工艺库综合,在50MHz的时钟频率下工作时电路规模仅需1.6万门左右。 相似文献
78.
Haci A. Mantar Ibrahim T. Okumus Junseok Hwang Steve J. Chapin 《International Journal of Communication Systems》2008,21(8):843-861
Bandwidth brokers (BBs) have been proposed for providing end‐to‐end quality of services (QoS) in differentiated services (Diffserv) networks. As a single entity in each domain, a BB aims at performing both intra‐ and inter‐domain resource management on behalf of its domain. There have been plenty of BB studies for intra‐domain resource management. However, how a BB can perform inter‐domain resource management in a scalable and deployable manner is still an open issue. In this work, we present the design, implementation and evaluation of an inter‐BB communication protocol that is used by each BB to communicate with its neighboring BBs for inter‐domain QoS resource management. The proposed model uses a destination‐based aggregation scheme in which reservations are aggregated as they merge through the destination region. The destination‐based aggregation improves inter‐domain state and signaling scalability. The protocol also performs traffic engineering to increase inter‐domain resource utilization. The implementation and simulation results verify the achievements of our model. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
79.
80.
The dynamic cellular facility layout problem (DCFLP) is a well-known NP-hard problem. It has been estimated that the efficient design of DCFLP reduces the manufacturing cost of products by maintaining the minimum material flow among all machines in all cells, as the material flow contributes around 10–30% of the total product cost. However, being NP hard, solving the DCFLP optimally is very difficult in reasonable time. Therefore, this article proposes a novel similarity score-based two-phase heuristic approach to solve the DCFLP optimally considering multiple products in multiple times to be manufactured in the manufacturing layout. In the first phase of the proposed heuristic, a machine–cell cluster is created based on similarity scores between machines. This is provided as an input to the second phase to minimize inter/intracell material handling costs and rearrangement costs over the entire planning period. The solution methodology of the proposed approach is demonstrated. To show the efficiency of the two-phase heuristic approach, 21 instances are generated and solved using the optimization software package LINGO. The results show that the proposed approach can optimally solve the DCFLP in reasonable time. 相似文献