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Building a next generation Internet with source address validation architecture

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Science in china(Series F) 2008年第11期51卷 1681-1691页

作者： WU JianPing1,3,REN Gang1,3 & LI Xing2,3 1 department of Computer Science,Tsinghua university,beijing 100084.china 2 department of electronic engineering,Tsinghua university,beijing 100084.china 3 Tsinghua National Laboratory for information Science and Technology(TNList) ,beijing 100084.china department of Computer Science Tsinghua University Beijing 100084 China department of electronic engineering Tsinghua University Beijing 100084 China Tsinghua National Laboratory for information Science and Technology (TNList) Beijing 100084 China

The IP packet forwarding of current Internet is mainly destination based. In the forwarding process, the source IP address is not checked in most *** causes serious security, management and accounting problems. Based on the drastically increased IPv6 address space, a ＂source address validation architecture＂（SAVA） is proposed in this paper, which can guarantee that every packet received and forwarded holds an authenticated source IP address. The design goals of the architecture are lightweight, loose coupling, ＂multi-fence support＂ and incremental deployment. This paper discusses the design and implementation for the architecture, including inter-AS, intra-AS and local subnet. The performance and scalability of SAVA are described. This architecture is deployed into the CNGI-CERNET2 infrastructure a large-scale native IPv6 backbone network of the china Next Generation Internet project. We believe that the SAVA will help the transition to a new, more secure and dependable Internet.

关键词： IP source address validation network architecture network security

Computer simulation on reliability of retention index with FDG-PET and optimization of dual-time-point imaging protocol

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Progress in Natural Science:Materials International 2008年第8期18卷 931-937页

作者： Rui Jia a, Jing Bai a,*, Lingfeng Wenb,c, Dagan Fengb,c a department of Biomedical engineering, Tsinghua university, Room B209, Building of Medical Science, beijing 100084. {4. b School of information Technologies, university of Sydney, NSW 2006, Australia c department of electronic and information engineering, Hong Kong Polytechnic university, Hong Kong department of Biomedical engineering Tsinghua University Room B209 Building of Medical Science Beijing 100084 China School of information Technologies University of Sydney NSW 2006 Australia department of electronic and information engineering Hong Kong Polytechnic University Hong Kong

The inherent noise in positron emission tomography (PET) leads to the instability of quantitative indicators, which may affect the diagnostic accuracy for differentiating malignant and benign lesions in the management of lung cancer. In this paper, the reliability of retention index (RI) is systematically investigated by using computer simulation for the dual-time-point imaging protocol. The area under the receiver operating characteristic (ROC) curve is used to evaluate the optimal protocol. Results demonstrate that the reliability of RI is affected by several factors including noise level, lesion type, and imaging schedule. The RIs with small absolute values suffer from worse reliability than those larger ones. The results of ROC curves show that over delayed second scan cannot help to improve the diagnostic performance further, while an early first scan is expected. The method of optimization based on ROC analysis can be easily extended to comprise as many lesions as possible.

关键词： Reliability Retention index PET (positron emission tomography) Simulation ROC (receiver operating characteristic)

Fusing Global and Regional Features for Image Classification

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Fusing Global and Regional Features for Image Classification

Invasive mechanism and management strategy of Bemisia tabaci(Gennadius) biotype B:Progress report of 973 Program on invasive alien species in china

2009中国控制与决策会议

作者： Xiaohong Hu~(1,2),Xu Qian~2 1.School of information and management Science,Henan agricultural university,Zhengzhou,4.0002,{4. 2.School of Mechanical electronic and information engineering,{4. university of Mining and Technology,beijing,100083.{4.

＜正＞This paper presents a novel approach to image classification based on the fusion of global and regional features,which are helpful to describe image semantics to classification,in which vague sets for positive and negative evidences is applied to analyze and optimize the decisions obtained by *** integrating two sides of multiple classification decisions,the classification is optimized and synthesized,thus the processing and results will be both powerful and *** results show that the performance of the classification is greatly improved.

关键词： vague set decision fusion support vector machine

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Science china(Life Sciences) 2009年第1期52卷 88-95页

作者： WAN FangHao1,ZHANG GuiFen1,LIU ShuSheng2,LUO Chen3,CHU Dong4.ZHANG YouJun4.ZANG LianSheng2,JIU Min2,Lü ZhiChuang1,CUI XuHong1,ZHANG LiPing4.ZHANG Fan3,ZHANG QingWen5,LIU WanXue1,LIANG Pei5,LEI ZhongRen1 & ZHANG YongJun1 1 State Key Laboratory for Biology of Plant Diseases and Insect Pests,Institute of Plant Protection,Chinese Acadeny of Agriculture Sciences,beijing 100094.china 2 Institute of Applied Entomology,Zhejiang university,Hangzhou 310029,china 3 Institute of Plant and Environment Protection,beijing Academy of agricultural and Forestry Sciences,beijing 100089,china 4.Institute of Vegetables and Flowers,Chinese Acadeny of Agricullare Sciences,beijing 100081,china 5 department of Entomology,china Agriculture university,beijing 100094.china 1. State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant Protection Chinese Acadeny of Agriculture Sciences Beijing 100094 China 2. Institute of Applied Entomology Zhejiang University Hangzhou 310029 China 3. Institute of Plant and Environment Protection Beijing Academy of Agricultural and Forestry Sciences Beijing 100089 China 4. Institute of Vegetables and Flowers Chinese Acadeny of Agricullare Sciences Beijing 100081 China 5. department of Entomology China Agriculture University Beijing 100094 China

Bemisia tabaci(Gennadius) biotype B,called a "superbug",is one of the most harmful biotypes of this species complex *** this report,the invasive mechanism and management of *** biotype B,based on our 5-year studies,are *** *** biotypes,B,Q,ZHJ1,ZHJ2,ZHJ3 and FJ1,have been identified in *** B dominates the other biotypes in many regions of the *** diversity in biotype B might be induced by host plant,geographical conditions,and/or insecticidal *** activities of CarE(carboxylesterase) and GSTs(glutathione-S-transferase) in biotype B reared on cucumber and squash were greater than on other host plants,which might have increased its resistance to *** higher activities of detoxification enzymes in biotype B might be induced by the secondary metabolites in host *** adaptive ability of biotype B adults to adverse conditions might be linked to the expression of heat shock protein *** indigenous *** biotypes were displaced by the biotype B within 225 *** asymmetric mating interactions and mutualism between biotype B and begomoviruses via its host plants speed up widespread invasion and displacement of other *** biotype B displaced Trialeurodes vaporariorum(Westwood) after 4.7 generations under glasshouse *** adaptive ability of the biotype B to adverse conditions and its rapid population increase might be the reasons of its successful displacement of *** ability of the biotype B to switch to different host plants may enrich its host plants,which might enable it to better compete with *** predatory natural enemies possess greater ability to suppress *** under field *** kairomones in the 3rd and 4.h instars of biotype B may provide an important stimulus in host searching and location by its *** present results provide useful information in explaining the mechanisms of genetic diversity,e

关键词： National Basic Research and Development Program of china(973 Program) invasive alien species Bemisia tabaci biotype B ecological mechanisms genetic diversity sustainable management

A LOW POWER TIME-TO-DIGITAL CONVERTER FOR ALL-DIGITAL PHASE-LOCKED LOOP

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Journal of electronics(china) 2011年第3期28卷 402-408页

作者： Yu Guangming Wang Yu Yang Huazhong department of electronic engineering Tsinghua National Laboratory for Information Science and Technology （ TNList） Tsinghua University Beijing 100084 China

Time-to-Digital Converter (TDC) is a key block used as the phase/frequency detector in an All-Digital Phase-Locked Loop (ADPLL). Usually, it occupies a large proportion of ADPLL's total power consumption up to about 30% to 4.%. In this paper, the detailed power consumption of different components in the TDC is analyzed. A Power management Block (PMB) is presented for the TDC to reduce its power consumption. A 24.bits TDC core with the proposed PMB is implemented in HJTC 0.18 μm CMOS technology. Simulation results show that up to 84. power reduction is achieved using our proposed technique.

关键词： Low power Power management All-Digital Phase-Locked Loop (ADPLL) Time-to-Digital Converter (TDC)

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一种基于有限自动机的软件工作流开发模型

计算机工程与应用 2004年第28期40卷 208-211页

作者：敖丽敏王树大郭永洪中国农业大学信息与电气工程学院东北电力学院信息工程系吉林132012 东北电力学院信息工程系中国农业大学经济管理学院

软件开发模型很多,基于Web的三层结构的软件设计开发模型的关键是要考虑它的并发性。文章提出了一种基于有限自动机的Web软件开发模型。该模型对有限自动机进行了扩充;将扩充后的有限自动机转换成为分层状态图;根据分层状态图转换成为... 详细信息

软件开发模型很多,基于Web的三层结构的软件设计开发模型的关键是要考虑它的并发性。文章提出了一种基于有限自动机的Web软件开发模型。该模型对有限自动机进行了扩充;将扩充后的有限自动机转换成为分层状态图;根据分层状态图转换成为多功能视图;在此基础上进行软件开发。利用这个开发模型可以方便地进行需求分析和描述;只需开发子服务组件或模块,便可进行软件开发、系统扩充以及后来的系统重构。

关键词：软件开发模型有限自动机软件工作流分层状态图重构

Robust Image Annotation Refinement via Graph-Based Learning

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Robust Image Annotation Refinement via Graph-Based Learning

SPATIAL COMPATIBLE USER GROUPING ALGORITHM FOR MULTIUSER MIMO SYSTEMS

2009中国控制与决策会议

作者： Xiaohong Hu~(1,2),Xu Qian ~2,Lei Xi~1,Xinming Ma~1 1.School of information and management Science,Henan agricultural university,Zhengzhou,4.0002,{4. 2.School of Mechanical electronic and information engineering,{4. university of Mining and Technology,beijing,100083.{4.

＜正＞Image annotation has been an active research topic in recent ***,the state of art image annotation methods are often unsatisfactory,in this paper,we presented a novel image annotation refinement to improve the performance of automatic image ***,the initial pair-wise similarities of words is computed based on the co-occurrence of training sets,Then the topic relation is mined by generating the topic ***,the candidate annotations are re-ranked by embedding the refined word relation. The experiments over Corel images have shown that embedding topic relation is beneficial in image annotation.

关键词： image annotaion graph-based learning label propagation

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Journal of electronics(china) 2007年第2期24卷 257-260页

作者： Li Lei Niu Zhisheng department of electronic engineering Tsinghua University Beijing 100084 China

A spatial compatible user grouping algorithm is proposed to reduce CoChannel Interference (CCI) in Space Division Multiple Access (SDMA) multiuser Multiple Input Multiple Output (MIMO) systems. We evaluate the interferences among users by use of distances between row spaces spanned by users’ channel matrixes, then control frequency sharing according to the compatible user grouping algorithm. Results show that the row space distance algorithm outperforms others because it can fully utilize the information from users’ channel matrixes, especially the matrix structure information. The results also prove that the algorithm based on channel matrix structure analysis is a better candidate for spatial compatibility approximation.

关键词： Multiple Input Multiple Output (MIMO) Space Division Multiple Access (SDMA) Multiuser system Radio resource management

Fault Diagnosis System Based on Self-Adaption Test for Combined Logic Circuits

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Fault Diagnosis System Based on Self-Adaption Test for Combi...