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991.
近年来,支持多标准的LDPC译码器已逐渐成为研究的热点.与传统译码器相比,所设计的LDPC译码器具有以下优点:1.实现了一个码率、码长可配置结构,进而可以支持多种标准;2.采用了一种改进型TPMP算法,使译码器的存储器容量大大减少,避免了因分块LDPC码的非规则性所造成的数据冲突问题;3.采用基于SIMD处理器的硬件结构,实现了硬件的高度规整性,易于芯片布局布线;4.设计了一个6级可配置流水线,可分时构造校验节点处理单元和变量节点处理单元,提高了硬件利用率和系统数据吞吐率.用这种架构实现了一个同时支持CMMB和DTMB两个标准的多标准LDPC译码器;芯片规模为75万门,时钟频率为220MHz,数据吞吐率为300Mbps. 相似文献
992.
物联网环境下智能插座的设计 总被引:2,自引:0,他引:2
实时反馈机制被普遍认为是一种有效的节能方式,同时物联网技术使这种方式变得更为舒适便捷.提出在物联网环境下使用智能插座来实现电能的实时反馈.详细介绍了构成智能插座的电源模块、电能传感模块、电器通断模块、存储模块、处理器和无线通信模块的设计.此外还对电源模块、无线通信模块、电能传感模块、以及实际的节能效果方面进行了测试验证. 相似文献
993.
WSN中的质心定位算法研究 总被引:1,自引:0,他引:1
节点定位是无线传感器网络(WSN)中的关键技术之一。通过对质心定位算法的分析,提出了一种改进的质心算法(CSA)——以距离未知节点最近的锚节点为基准找出差异性最大的估计点,采用三角质心和多边质心计算估计点坐标提高定位精度。通过MATLAB仿真表明算法是有效可行的。 相似文献
994.
1958(2)
Manifold-ranking based topic-focused multi-document summarization
2007
An Introduction to Kolmogorov Complexity and Its Applications
1997
The use of MMR,diversity-based reranking for reordering documents and producing summaries
1998
Centroid-based summarization of multiple documents
2004(6)
A trainable document summarizer
1995
Impact of linguistic analysis on the semantic graph coverage and learning of document extracts
2005
Document summarization using conditional random fields
2007
Adasum:An adaptive model for summarization
2008
Lexpagerank:Prestige in multidocument text summarization
2004
Mihalcea R.Taran P
Textrank-Bring order into texts
2004
Mihalcea R.Tarau P
A language independent algorithm for single and multiple document summarization
2005
Wan X.Yang J.Xiao J
Towards an iterative reinforcement approach for simultaneous document summarization and keyword extraction
2007
Wan X
An exploration of document impact on graph-based multi-document summarization
2008
Bennett C H.Gács P.Li M.Vitányi P M,Zurek W H
Information distance
1998(4)
Li M.Badger J H.Chen X.Kwong S,Kearney P,Zhang H
An information-based sequence distance and its application to whole mitochondrial genome phylogeny
2001(2)
Li M.Chen X.Li X.Ma B Vitányi P M
The similarity metric
2004(12)
Long C.Zhu X.Li M.Ma B
Information shared by many objects
2008
Benedetto D.Caglioti E.Loreto V
Language trees and zipping
2002(4)
Bennett C H.Li M.Ma B
Chain letters and evolutionary histories
2003(6)
Cilibrasi R L.Vitányi P M
The Google similarity distance
2007(3)
Zhang X.Hao Y.Zhu X.Li M
Information distance from a question to an answer
2007
Ziv J.Lempel A
A universal algorithm for sequential data compression
1977(3)
Lin C Y.Hovy E
Automatic evaluation of summaries using n-gram co-occurrence statistics
2003
Nenkova A.Passonneau R.Mckeown K
The pyramid method:Incorporating human content selection variation in summarization evaluation
2007(2)
995.
UNIFAC-DMD法预测烷烃-氨的汽液相平衡 总被引:3,自引:0,他引:3
烷烃-氨的汽液相平衡模型是计算爱因斯坦制冷循环的重要数据.然而在设计氨-水-异戊烷的爱因斯坦制冷循环的过程中,从文献中查阅不到异戊烷一氨的相平衡数据.采用商业软件中基团贡献法UNIFAC-DMD自带的数据库所预测的结果也不尽人意,不能得到特征的蝶形相图.本文利用基团贡献法的原理,通过使用模拟软件,应用文献中得到的丙烷-氨和正丁烷-氨体系的相平衡数据,拟合基团贡献法uNIFAC-DMD中的CH2、NH3的含对温度修正的基团交互参数aCH2NH3,1/K,aCH2NH3,2,aCH2NH3,3/K-1和aNH3CH3,1/K,aNH3CH3,2,aNH3CH3,3/K-1..拟合得到上述基团交互参数值分别为-1 995.4,18.51,-0.037,11 565.3,-68.98,和0.111 4.将此组新参数替换原有基团贡献法的数据库参数,重新预测烷烃-氨的相平衡,成功预测得到了蝶形相图. 相似文献
996.
Based on the edge-based array representation of loops in the topological graphs of kinematic chains, this paper first proposes
three arithmetic operations of loops. Then the concept of the independent loop set as well as its determination rules is introduced,
and a new structure decomposition algorithm of kinematic chains is presented. Based on the algorithm, an automatic and efficient
method for rigid sub-chain detection and driving pair selection of kinematic chains is proposed. Finally, an index is proposed
to assess computation complexity of kinematic analysis with respect to different driving pair selections. 相似文献
997.
Jianhan Zhu Xiangji Huang Dawei Song Stefan Rüger 《Knowledge and Information Systems》2010,23(1):29-54
We argue that expert finding is sensitive to multiple document features in an organizational intranet. These document features
include multiple levels of associations between experts and a query topic from sentence, paragraph, up to document levels,
document authority information such as the PageRank, indegree, and URL length of documents, and internal document structures
that indicate the experts’ relationship with the content of documents. Our assumption is that expert finding can largely benefit
from the incorporation of these document features. However, existing language modeling approaches for expert finding have
not sufficiently taken into account these document features. We propose a novel language modeling approach, which integrates
multiple document features, for expert finding. Our experiments on two large scale TREC Enterprise Track datasets, i.e., the
W3C and CSIRO datasets, demonstrate that the natures of the two organizational intranets and two types of expert finding tasks,
i.e., key contact finding for CSIRO and knowledgeable person finding for W3C, influence the effectiveness of different document
features. Our work provides insights into which document features work for certain types of expert finding tasks, and helps
design expert finding strategies that are effective for different scenarios. Our main contribution is to develop an effective
formal method for modeling multiple document features in expert finding, and conduct a systematic investigation of their effects.
It is worth noting that our novel approach achieves better results in terms of MAP than previous language model based approaches
and the best automatic runs in both the TREC2006 and TREC2007 expert search tasks, respectively. 相似文献
998.
999.
Taiwan is famous for its personal computer (PC) products, and this success demonstrates that Taiwanese manufacturers have effective strategies in managing supply chains of PC-related products. Among various strategies of supply chain management, achieving leagility is the main goal. The purpose of this study is to illustrate how a PC original equipment manufacturer (OEM) in Taiwan achieves leagility through reengineering its supply chain. The case study shows how the company adjusts its production processes from build-to-order (BTO) to configuration-to-order (CTO) to achieve leagility. Through this case study, some experiences of operating global logistics could be shared. 相似文献
1000.
Mobile devices could facilitate human interaction and access to knowledge resources anytime and anywhere. With respect to wide application possibilities of mobile learning, investigating learners’ acceptance towards it is an essential issue. Based on activity theory approach, this research explores positive factors for the acceptance of m-learning systems. In the research, we developed an m-learning system for learners’ knowledge management and invited 152 participants who knew how to use the m-learning system then report on their experience. The results show that enhancing learners’ satisfaction, encouraging learners’ autonomy, empowering system functions, and enriching interaction and communication activities have a significant positive influence on the acceptance of m-learning systems. 相似文献