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61.
【】高效视频编码(HEVC)算法支持的帧内预测模式扩展到了35种,使之可实现更精准的预测,从而取得更高的压缩率。本文通过分析图像数据DCT系数的特性,研究了DCT系数与帧内预测模式的映射关系,提出了一种DCT系数的分布特征与帧内预测模式间的映射方法,该方法可用于提高HEVC的编码速度。 相似文献
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63.
一种新的快速混合聚类算法 总被引:1,自引:1,他引:1
在汲取了传统划分、层次聚类方法优点的基础上,结合图搜索技术,提出了一种新的快速混合聚类算法.该算法主要分为三个步骤:首先将整个数据集"压碎",生成固定数量的原子级聚类;然后处理孤立点;最后采用图搜索技术生成聚类.该算法只需一个参数,能识别任意形状、大小的聚类,时间复杂度在最坏情况下为nn~(1/2).实验表明该算法是有效的. 相似文献
64.
Sze-Yao Li Chun-Ming Chang Yuan-Yu Tsai Seth Chen Jonathan Tsai Wen-Lung Tsai 《中国电子科技》2013,11(2):169-175
For a transaction processing system to operate effectively and efficiently in cloud environments, it is important to distribute huge amount of data while guaranteeing the ACID (atomic, consistent, isolated, and durable) properties. Moreover, database partition and migration tools can help transplanting conventional relational database systems to the cloud environment rather than rebuilding a new system. This paper proposes a database distribution management (DBDM) system, which partitions or replicates the data according to the transaction behaviors of the application system. The principle strategy of DBDM is to keep together the data used in a single transaction, and thus, avoiding massive transmission of records in join operations. The proposed system has been implemented successfully. The preliminary experiments show that the DBDM performs the database partition and migration effectively. Also, the DBDM system is modularly designed to adapt to different database management system (DBMS) or different partition algorithms. 相似文献
65.
语音情感识别是人工智能的重要研究领域之一,特征参数提取的准确性直接影响识别的效果。分析了发音持续时间、平均振幅、基音频率,第一共振峰和Mel频率倒谱参数,并基于模糊熵理论提取了各参数的权重。再利用模糊熵进行有效的度量融合.最后通过改进后综合判决对情感语句做出识别判定。研究发现融合后的参数增强了情感识别的效果。 相似文献
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67.
HP4191A射频阻抗分析仪的测量原理是测量阻抗的反射系数,他具有自动校准功能,根据3个参考值的校准值自动修正反射系数的误差。首先介绍他的主要性能特点、测量原理、3个参考阻抗件的原理结构和标准值,然后通过公式推导重点介绍他的误差修正方法。 相似文献
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69.
In this paper, a four-stage method for synthesizing reconfigurable ASNoC topology is proposed for partially dynamically reconfigurable systems, where the topology is reconfigured dynamically at run-time along with the application's execution. Firstly, a simulated annealing based topology-aware integrated optimization framework is proposed to generate the proper schedule and floorplan of task modules. Secondly, based on the schedule and floorplan of task modules, an Integer Linear Programming (ILP)-based method and a heuristic method, are proposed to partition the communication requirements of the application into time intervals. Thirdly, we explore the proper positions of switches in the floorplan for global communications. Finally, considering the reconfiguration costs between adjacent time intervals, the routing path allocation problem is solved for time intervals in an iterative procedure to generate fine-grained dynamically reconfigurable ASNoC topologies. Experimental results show that, compared to the random partition of communication requirements, the proposed heuristic method and ILP-based method can achieve 5.4% and 10.0% power consumption improvement, respectively. And, the reconfigurable ASNoC can achieve 31.6% power consumption improvement when compared with static ASNoC. 相似文献
70.
In recent years, the light field (LF) as a new imaging modality has attracted wide interest. The large data volume of LF images poses great challenge to LF image coding, and the LF images captured by different devices show significant differences in angular domain. In this paper we propose a view prediction framework to handle LF image coding with various sampling density. All LF images are represented as view arrays. We first partition the views into reference view (RV) set and intermediate view (IV) set. The RVs are rearranged into a pseudo sequence and directly compressed by a video encoder. Other views are then predicted by the RVs. To exploit the four dimensional signal structure, we propose the linear approximation prior (LAP) to reveal the correlation among LF views and efficiently remove the LF data redundancy. Based on the LAP, a distortion minimization interpolation (DMI) method is used to predict IVs. To robustly handle the LF images with different sampling density, we propose an Iteratively Updating depth image based rendering (IU-DIBR) method to extend our DMI. Some auxiliary views are generated to cover the target region and then the DMI calculates reconstruction coefficients for the IVs. Different view partition patterns are also explored. Extensive experiments on different types LF images also valid the efficiency of the proposed method. 相似文献