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Eavesdropping in a quantum secret sharing protocol based on Grover algorithm and its solution

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science China(Physics,Mechanics & Astronomy) 2010年第3期53卷 491-495页

作者： HAO Liang1, LI JunLin1 & LONG GuiLu1,2 1Key laboratory for Atomic and Molecular Nanosciences and Department of Physics, tsinghua university, Beijing 100084, China 2tsinghua national laboratory for information science and technology, Beijing 100084, China 1. Key laboratory for Atomic and Molecular Nanosciences and Department of Physics Tsinghua University Beijing 100084 China2. Tsinghua National Laboratory for Information Science and Technology Beijing 100084 China

A detailed analysis has showed that the quantum secret sharing protocol based on the Grover algorithm (Phys Rev A, 2003, 68: 022306) is insecure. A dishonest receiver may obtain the full information without being detected. A quantum secret-sharing protocol is presents here, which mends the security loophole of the original secret-sharing protocol, and doubles the information capacity.

关键词： quantum secret sharing Grover algorithm quantum cryptography quantum search algorithm

A Feedback Scheme for Fountain Codes Based Transport Protocol in Space Communications

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China Communications 2015年第8期12卷 62-72页

作者： XING Yanling GE Ning tsinghua national laboratory for information science and technology Department of Electronic Engineering Tsinghua University Aerospace Communications and Terminal Application Technologies Engineering laboratory in Shenzhen

This paper proposed a practical- feedback scheme for fountain codes based transportprotocol in space communications. In the proposed scheme, the sender is signaled by two types of acknowledgment （ACK） *** decoding, packet loss probability isestimated on the receiver side and encapsulated intoa soft ACKand sent to the *** decoding,decoding results are encapsulated into hard ACKsandsent to the sender. There are two contributionsin the proposed scheme： 1. Empl layer calculation instead layer statistics to estimate oying physical of application the packet loss probability of space channel, which can improvethe accuracy and practicality. 2. A cascade overhead-failure probability relationship between the sender and the receiver has been analyzed to help determine the exact numberof packetsneeded byfountain *** show that for space communications,compared with the existing space transport protocols, fountain codes based transport protoeolwith the proposed schemecan not only ensure transmission reliability, but also greatly improvelink utilization.

关键词： fountain code feedback spacecommunication packet loss probabilityestimation transport protocol

Self-healing routing: failure,modeling and analysis

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science China(information sciences) 2011年第3期54卷 609-622页

作者： XU MingWei 1,2 , LI Qi 1,2 , YANG Yuan 1,2 , HOU MeiJia 1,2 & PAN LingTao 1,2 1 Department of Computer science, tsinghua university, Beijing 100084, China 2 tsinghua national laboratory for information science and technology (TNList), Beijing 100084, China 1. Department of Computer science Tsinghua University Beijing 100084 China2. Tsinghua National Laboratory for Information Science and Technology (TNList) Beijing 100084 China

Network failures occur frequently, and self-healing ability of existing routing protocols cannot guarantee fast route convergence under these failures without impacting packet forwarding. During routing convergence, network routes may be incorrect and even routing black holes and loops occur, which will result in extensive packet loss and thus influence network performance. To solve this problem, several improved routing solutions have been proposed. In this paper, we propose the concept and model of self-healing routing and analyze the key problems in current intra-domain and inter-domain self-healing routing protocols after briefly reviewing the characteristics of network failures. We classify the different self-healing solutions into two categories based on their design principles: routing restoration and routing protection, and systematically analyze these different typical solutions. Finally, we discuss several key issues in self-healing routing and propose a hybrid protection and restoration based routing scheme.

关键词： failure intra-domain routing inter-domain routing self-healing routing

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

A TTCN-3-based protocol testing system and its extension

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science in China(Series F) 2008年第11期51卷 1703-1722页

作者： YIN Xia1,3,WANG ZhiLiang2,3,JING ChuanMing1,3 & SHI XinGang2,3 1 Department of Computer science and technology,tsinghua university,Beijing 100084,China 2 Network Research Center,tsinghua university,Beijing 100084,China 3 tsinghua national laboratory for information science and technology(TNList) ,Beijing 100084,China 1. Department of Computer science and technology Tsinghua University Beijing 100084 China 3. ]tsinghua national laboratory for information science and technology (TNList) Beijing 100084 China 2. Network Research Center Tsinghua University Beijing 100084 China

The protocol testing technology used in the next generation Internet should satisfy some new challenges and requirements. This paper focuses on the test suite description and test implementation techniques. TTCN-3 is chosen as the test suite description language and extended in both syntax and semantics to satisfy the requirements of protocol robustness testing. PITSv3, a protocol integrated testing system based on TTCN-3, is developed, and the extensions for robustness testing are implemented. Finally, two practical test applications are presented.

关键词： protocol testing TTCN-3 PITSv3 robustness testing

Influence of magnetic current on the ground state entanglement in an isotropic transverse XY chain

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Progress in Natural science:Materials International 2007年第10期17卷 1147-1151页

作者： Liu Dan1,2 , Zhang Yong3 and Long Guilu1,2(1. Key laboratory for Atomic and Molecular Nanosciences, and Department of Physics, tsinghua university, Beijing 100084, China 2. Center of Quantum information science and technology, tsinghua national laboratory for information science and technology, Beijing 100084, China 3. Institute of Physics, School of sciences, Beijing university of Posts and Telecommunications, Beijing 100876, China) Key laboratory for Atomic and Molecular Nanosciences and Department of Physics Tsinghua University Beijing 100084 China Center of Quantum information science and technology Tsinghua National Laboratory for information Science and Technology Beijing 100084 China Institute of Physics School of Sciences Beijing University of Posts and Telecommunications Beijing 100876 China

We study the ground state entanglement in a three-qubit XY chain under the influence of a magnetization current. It is found that the ground state changes from a W state to a disentangled state as the magnetic field varies. When the Lagrange multiplier λ>3, namely under a strong magnetic current, the ground state holds onto a W state for a large range of the magnetic field strength. A phase transition to the magnetization-current phase occurs under a certain condition.

关键词： Heisenberg-XY chain magnetic-current phase transition.

Development of silicon-based microelectrode array

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science China(Technological sciences) 2009年第8期52卷 2391-2395页

作者： LIN JianHui1,2,3, WU XiaoMing1,2,3,4, HUANG PengSheng1,2, FENG Lei5, REN TianLing1,2 & LIU LiTian1,2 1 Institute of Microelectronics, tsinghua university, Beijing 100084, China 2 tsinghua national laboratory for information science and technology, Beijing 100084, China 3 Yangtze Delta Region Institute of tsinghua university, Jiaxing 314050, China 4 State Key laboratory of Transducer technology, Chinese Academy of sciences, Shanghai 200050 China 5 Department of Biomedical Engineering, tsinghua university, Beijing 100084, China 1. Institute of Microelectronics Tsinghua University Beijing 100084 China 2. tsinghua national laboratory for information science and technology Beijing 100084 China 3. Yangtze Delta Region Institute of tsinghua university Jiaxing 314050 China 4. State Key laboratory of Transducer technology Chinese Academy of Sciences Shanghai 200050 China 5. Department of Biomedical Engineering Tsinghua University Beijing 100084 China

This paper introduces in details a kind of silicon-based microelectrode array. MEMS (micro-electromechanical system) technology is used in the fabrication of the microelectrode array, which is designed to perform signal recording and electrical stimulation for nerves in neural engineering. A simple fabrication process is developed. An improved model of microelectrodes is brought forward and successfully validated by the excellent match between circuit simulations and electrical measurements, including both magnitude and phase of microelectrode impedance. Compared with the simple one that is usually used, the improved model is believed to be an advance and more accurate. This modeling helps to improve the design of microelectrodes and understand the behavior of interface between electrode and cell. Furthermore, the microelectrode is proved to be a feasible tool for researches in neural engineering by successfully recording neural activities of sciatic nerve of a bullfrog.

关键词： microelectrode array MEMS neural engineering

An N/4 fixed-point duality quantum search algorithm

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中国科学：物理学、力学、天文学英文版 2010年第9期53卷 1765-1768页

作者： HAO Liang1,LIU Dan2 & LONG GuiLu1,3 1Key laboratory for Atomic and Molecular Nanosciences and Department of Physics,tsinghua university,Beijing 100084,China 2School of sciences,Dalian nationalities university,Dalian 116600,China 3tsinghua national laboratory for information science and technology,Beijing 100084,China 1. Key laboratory for Atomic and Molecular Nanosciences and Department of Physics Tsinghua University Beijing 100084 China2. School of Sciences Dalian Nationalities University Dalian 116600 China3. Tsinghua National Laboratory for Information Science and Technology Beijing 100084 China

Here a fixed-point duality quantum search algorithm is *** algorithm uses iteratively non-unitary operations and measurements to search an unsorted *** the marked item is found,the algorithm stops *** algorithm uses a constant non-unitary operator,and requires N/4 steps on average(N is the number of data from the database) to locate the marked *** implementation of this algorithm in a usual quantum computer is also demonstrated.

关键词： fixed-point search algorithm duality quantum computing the N4 duality search algorithm

Online multiple instance regression

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Chinese Physics B 2013年第9期22卷 656-661页

作者：王志岗赵增顺张长水 Department of Automation Tsinghua UniversityState Key Laboratory of Intelligent Technologie and SystemsTsinghua National Laboratory for Information Science and Technology College of information and Electrical Engineering Shandong University of Science and Technology School of Control science and Engineering Shandong University

The multiple instance regression problem has become a hot research topic recently. There are several approaches to the multiple instance regression problem, such as Salience, Citation KNN, and MI-ClusterRegress. All of these solutions work in batch mode during the training step. However, in practice, examples usually arrive in sequence. Therefore, the training step cannot be accomplished once. In this paper, an online multiple instance regression method ＂OnlineMIR＂ is proposed. OnlineMIR can not only predict the label of a new bag, but also update the current regression model with the latest arrived bag. The experimental results show that OnlineMIR achieves good performances on both synthetic and real data sets.

关键词： mutiple instance regression online learning