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Novel algorithm for communication signal blind separation-EASIBSA algorithm

Wuhan Ligong Daxue Xuebao/Journal of Wuhan University of technology 2008年第1期30卷 91-94页

作者： Fu, Wei-Hong Yang, Xiao-Niu Liu, Nai-An Zeng, Xing-Wen State Key Lab. of Integrated Service Networks Xidian University Xi'an 710071 China National Laboratory of Information Control Technology for Communication System Jiangnan Electronic Communications Research Institute Jiaxing 314033 China

Aim at the problem of the communication signal blind source separation, a novel blind separation algorithm based on step size adaptation (EASIBSA) to increase the convergence rate of the separation algorithm was present by using the idea of parameter adaptation optimization, which was based on Equivariant Adaptive Separation via Independent (EASI) algorithm. This algorithm related the learning rate with the object function and adapted it by using the stochastic gradient method, which avoided the selection of optimum learning rate and speed up the convergence rate. Simulation results showed that improved algorithm could increase the convergence rate of separation algorithm by two times without affecting the separation capability.

关键词： Blind source separation Convergence rate Digital communication Parameter adaptation

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Comparative study on preparation of biodiesel under microwave irradiation

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Yadian Yu Shengguang/Piezoelectrics and Acoustooptics 2008年第SUPPL. 2期30卷 42-43+45页

作者： Liu, Zuo-Hua Tao, Chang-Yuan Du, Jun Xu, Jiang-He Liu, Ren-Long State Key Lab. of Power Transmission Equipment and System Safety and New Technology College of Electrical Engineering Chongqing University Chongqing 400044 China College of Chemistry and Chemical Engineering Chongqing University Chongqing 400044 China College of Environmental and Biological Engineering Chongqing Technology and Business University Chongqing 400067 China

The interphase between the immiscible of oil and methanol leads to low reaction rate in biodiesel manufacturing. Comparative experiments were carried out to explore the different methods on yield of biodiesel based on the vegetable oil, methanol and ionic liquids. The routes for preparation of biodiesel were microwave-sulfuric acid-ionic liquid, microwave-alkaline-ionic liquid, conventional heating-sulfuric acid-ionic liquid. For the microwave-sulfuric acid-ionic liquid system with molar ratio of methanol to oil 12:1, 1.5% ionic liquid and 4, 0% sulfuric acid of mass of vegetable oil under microwave irradiation 800 W for 30 min at 65°C, the transesterification ratio was only 2.45%, while for the microwave-NaOH-ionic liquid system, the yield was 62.1% at 0.6 wt% NaOH of vegetable oil. Results indicated that for acid catalyst, microwave could inhibit the transesterification of biodiesel, but it could promote the yield of biodiesel and shorten the reaction time with alkaline catalyst.

关键词： Biodiesel Ionic liquid Microwave Transesterification

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A service-oriented priority-based resource scheduling scheme for virtualized utility computing 08

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Proceedings of the 15th international conference on High performance computing

作者： Ying Song Yaqiong Li Hui Wang Yufang Zhang Binquan Feng Hongyong Zang Yuzhong Sun Key Lab. of Computer System and Architecture Inst. of Computing Techn. Chinese Academy of Sciences China and National Research Center for Intelligent Computing Systems ICT China and Graduate Univ. of Chinese Academy of Sciences China Key Laboratory of Computer System and Architecture Institute of Computing Technology Chinese Academy of Sciences China and National Research Center for Intelligent Computing Systems ICT China

ISBN: (纸本)9783540898931

In order to provide high resource utilization and QoS assurance inutility computing hosting concurrently various services, this paper proposes aservice computing framework-RAINBOW for VM(Virtual Machine)-basedutility computing. In RAINBOW, we present a priority-based resourcescheduling scheme including resource flowing algorithms (RFaVM) to optimizeresource allocations amongst services. The principle of RFaVM is preferentiallyensuring performance of some critical services by degrading of others to someextent when resource competition arises. Based on our prototype, we evaluateRAINBOW and RFaVM. The experimental results show that RAINBOWwithout RFaVM provides 28%-324% improvements in service performance,and 26% higher the average CPU utilization than traditional service computingframework (TSF) in typical enterprise environment. RAINBOW with RFaVMfurther improves performance by 25%-42% for those critical services whileonly introducing up to 7% performance degradation to others, with 2%-8%more improvements in resource utilization than RAINBOW without RFaVM.

关键词： resource scheduling utility computing virtualization

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Mining the impact factors of threads and participators on usenet using link analysis

Mining the impact factors of threads and participators on us...

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11th Pacific-Asia Conference on Knowledge Discovery and Data Mining, PAKDD 2007

作者： Hongbo, Liu Jiaxin, Wang Yannan, Zhao Zehong, Yang State Key Lab. of Intelligent Technology and System Department of Computer Science and Technology Tsinghua University Beijing China

ISBN: (纸本)9783540717003

Usenet is a world-wide distributed discussion system, and it is one of the representative resources on Internet. The structure of newsgroup on Usenet forms gradually along with the evolution of the newsgroup and could provide helpful information for the users. In this paper, we present a method to evaluate the impact factors of participators and threads based on the structure of newsgroup. Some analysis and experimental results on real data sets are also provided. The impact factors could provide useful intrinsic information of the newsgroup and can be used in some applications to help access information more efficiently on the Usenet. The method can be also applied on other discussion systems, such as web forums, bulletin board systems, and so on. © Springer-Verlag Berlin Heidelberg 2007.

关键词： Data mining

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The feature and spatial covariant kernel: Adding implicit spatial constraints to histogram

The feature and spatial covariant kernel: Adding implicit sp...

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6th ACM International Conference on Image and Video Retrieval, CIVR 2007

作者： Liu, Xiaobing Wang, Dong Li, Jianmin Zhang, Bo State Key Lab. of Intelligent Technology and System Department of Computer Science and Technology Tsinghua University Beijing 100084 China

ISBN: (纸本)1595937331

In this paper, we are motivated to augment the holistic histogram representation with implicit spatial constrains. To be more concrete, we aim atending a good match function for the problem of object/scene categorization which considers the spatial constraints against heavy clutter and occlusion. Our solution is a partial match kernel under the histogram representation which varies simultaneously at both the feature and spatial resolutions, named as the Feature and Spatial Covariant (FESCO) kernel. Both the FESCO kernel and its late fusion alternative achieve better match accuracy than Spatial Pyramid Match[13] and Pyramid Match[11]. We also apply the keypoint features to video indexing. And on a large scale TRECVID data sets of over 300 hours videos, to our best knowledge, this approach achieves the state-of-the-art result for a single feature. Copyright 2007 ACM.

关键词： Image matching

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Adaptive multiple subtraction based on constrained independent component analysis 77

Adaptive multiple subtraction based on constrained independe...

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77th Society of Exploration Geophysicists International Exposition and Annual Meeting, SEG 2007

作者： Lu, Wen-Kai Liu, Lei Li, Yan-Dong Key State Lab. of Intelligent Technology and System Institute of Information Processing Department of Automation Tsinghua University China

ISBN: (纸本)9781604238976

Adaptive multiple subtraction is a critical and challenging procedure for the widely-used surface-related multiple attenuation (SRMA) techniques. The problem encountered in this field is that a good result is usually hard to obtain when primaries and multiples have overlap. In this paper, we propose a new adaptive multiple subtraction method based on constrained independent component analysis (CICA). In this method, the prediction error obtained by multidimensional prediction error filters (PEFs), which measure the lateral continuity of the primaries, is adopted as a constraint term in the objective function of CICA. The proposed method is demonstrated on two synthetic datasets. © 2007 Society of Exploration Geophysicists. All rights reserved.

关键词： Independent component analysis

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Random noise suppression based on discrete cosine transform 77

Random noise suppression based on discrete cosine transform

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77th Society of Exploration Geophysicists International Exposition and Annual Meeting, SEG 2007

作者： Lu, Wen-Kai Liu, Jun Key State Lab. of Intelligent Technology and System Institute of Information Processing Department of Automation Tsinghua University China

ISBN: (纸本)9781604238976

This paper illustrates the advantages of using the Discrete Cosine Transform (DCT) as compared to the standard Discrete Fourier Transform (DFT) for the purpose of removing random noise embedded in seismic data. The prediction filter is adopted in the DCT domain. Comparisons of the results between our method and the prediction filter in f-x domain show that the new method achieved better performance. © 2007 Society of Exploration Geophysicists. All rights reserved.

关键词： Discrete cosine transforms

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Video diver: Generic video indexing with diverse features

Video diver: Generic video indexing with diverse features

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International Multimedia Conference, MM'07 - 9th ACM SIG Multimedia International Workshop on Multimedia Information Retrieval, MIR'07

作者： Wang, Dong Liu, Xiaobing Luo, Linjie Li, Jianmin Zhang, Bo State Key Lab. of Intelligent Tech. and System Department of Computer Science and Technology Tsinghua University Beijing 100084 China

ISBN: (纸本)9781595937780

Semantic video indexing is critical for practical video retrieval systems and a generic and scalab.e indexing framework is a must for indexing a large semantic lexicon with over 1000 concepts present. This paper fully explores the idea of incorporating many kinds of diverse features into a single framework, combining them altogether to obtain larger degree of invariance which is absent in any of the component features, and thus achieves genericness and scalab.lity. We scale down the formidable computational expense with a clever design of the classification and fusion schemes. To be specific, ~20 kinds of diverse features are extracted to capture limited yet complementary variance in color, texture and edge with spatial constraints implicitly integrated, and over 100 classifiers are built subsequently and fused to produce a generic detector. The extensive experiments on a total of 310 hours of TRECVID news videos show that the proposed framework yields significantly improved performance over that of the best single feature across a variety of concepts. Moreover, a benchmark comparison demonstrates that this approach is state-of-the-art. Meanwhile, the proposed approach generalizes well over previously unseen programs and stations and scales well to a lexicon of over 300 concepts in the LSCOM [18] ontology. Copyright 2007 ACM.

关键词： Indexing (of information)

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Video search in concept subspace: A text-like paradigm 07

Video search in concept subspace: A text-like paradigm

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6th ACM International Conference on Image and Video Retrieval, CIVR 2007

作者： Li, Xirong Wang, Dong Li, Jianmin Zhang, Bo State Key Lab. of Intelligent Tech. and System Department of Computer Science and Technology Tsinghua University Beijing 100084 China

ISBN: (纸本)1595937331

Though both quantity and quality of semantic concept detection in video are continuously improving, it still remains unclear how to exploit these detected concepts as semantic indices in video search, given a specific query. In this paper, we tackle this problem and propose a video search framework which operates like searching text documents. Noteworthy for its adoption of the well-founded text search principles, this framework first selects a few related concepts for a given query, by employing a tf-idf like scheme, called c-tf-idf, to measure the informativeness of the concepts to this query. These selected concepts form a concept subspace. Then search can be conducted in this concept subspace, either by a Vector Model or a Language Model. Further, two algorithms, i.e., Linear Summation and Random Walk through Concept-Link, are explored to combine the concept search results and other baseline search results in a reranking scheme. This framework is both effective and efficient. Using a lexicon of 311 concepts from the LSCOM concept ontology, experiments conducted on the TRECVID 2006 search data set show that: when used solely, search within the concept subspace achieves the state-of-the-art concept search result;when used to rerank the baseline results, it can improve over the top 20 automatic search runs in TRECVID 2006 on average by approx. 20%, on the most significant one by approx. 50%, all within 180 milliseconds on a normal PC. Copyright 2007 ACM.

关键词： Semantics

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The importance of query-concept-mapping for automatic video retrieval

The importance of query-concept-mapping for automatic video ...

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15th ACM International Conference on Multimedia, MM'07

作者： Wang, Dong Li, Xirong Li, Jianmin Zhang, Bo State Key Lab. of Intelligent Tech. and System Department of Computer Science and Technology Tsinghua University Beijing 100084 China

ISBN: (纸本)9781595937025

A new video retrieval paradigm of query-by-concept emerges recently. However, it remains unclear how to exploit the detected concepts in retrieval given a multimedia query. In this paper, we point out that it is important to map the query to a few relevant concepts instead of search with all concepts. In addition, we show that solving this problem through both text and image inputs are effective for search, and it is possible to determine the number of related concepts by a language modeling approach. Experimental evidence is obtained on the automatic search task of TRECVID 2006 using a large lexicon of 311 learned semantic concept detectors. Copyright 2007 ACM.

关键词： Image retrieval

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