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Timeliness evaluation of task-oriented networked space-based information system

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Journal of Systems Engineering and Electronics 2011年第4期22卷 621-627页

作者： Chen Chen 1,2,and Jie Chen 2,3.1.Department of Automation,tsinghua University,beijing 100084,P.R.China 2.School of Automation,beijing Institute of {3.,beijing 100081,P.R.China 3.Complex System Intelligent Control and Decision,Ministry of Education,beijing 100081,P.R.China Department of Automation Tsinghua University Beijing 100084 P. R. China School of Automation Beijing Institute of Technology Beijing 100081 P. R. China School of Automation Beijing Institute of Technology Beijing 100081 P. R. China Complex System Intelligent Control and Decision Ministry of Education Beijing 100081 P. R. China

Task-oriented networked information system is an integrated information system which builds on multi-satellite networking to accomplish one or more tasks. In the background of emer- gency relief for applications, system working flow and response process are analyzed, and a timeliness effectiveness evaluation index system is constructed at multi-task level. The effectiveness is a measurement of promptness of information return. In evalua- tion process, system performance and tasks are associated, then an evaluation model based on efficacy function is established, and different evaluation criteria are selected for different tasks. A distributed simulation system is constructed, and the execution of task is decomposed. The simulation platform provides a comprehensive data source for evaluation. The results are easy to compare with each other, which reflects system time efficiency in different satellites networks and provides actual systems with basis and reference for design and application.

关键词： timeliness efficacy function space-based informationsystem simulation system.

Effect of carbon source on the denitrification in constructed wetlands

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Journal of Environmental sciences 2009年第8期21卷 1036-1043页

作者： LU Songliu, HU Hongying, SUN Yingxue, YANG Jia ESPC State Key Joint laboratory, Department of Environmental science and Engineering, tsinghua University, {3., China. [a]ESPC State Key Joint laboratory Department of Environmental Science and Engineering Tsinghua University Beijing 100084 China

The ability of constructed wetlands with different plants in nitrate removal were investigated. The factors promoting the rates of denitrification including organic carbon, nitrate load, plants in wetlands, pH and water temperature in field were systematically investigated. The results showed that the additional carbon source （glucose） can remarkably improve the nitrate removal ability of the constructed wetland. It demonstrated that the nitrate removal rate can increase from 20% to more than 50% in summer and from 10% to 3.% in winter, when the nitrate concentration was 3.-40 rag/L, the retention time was 24 h and 25 mg/L dissolved organic carbon （DOC） was ploughed into the constructed wetland. However, the nitrite in the constructed wetland accumulated a little with the supply of the additional carbon source in summer and winter, and it increased from 0.15 to 2 mg/L in the effluent. It was also found that the abilities of plant in adjusting pH and temperature can result in an increase of denitrification in wetlands. The seasonal change may also impact the denitrification.

关键词： constructed wetland carbon source denitrification nitrate nitrite

Cloning and characterization of 3. kDa laminin receptor precursor in pearl oyster,Pinctada fucata

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Progress in Natural science:Materials International 2008年第2期18卷 233-238页

作者： Yaopeng Fu a,Liping Xie a,b,,Rongqing Zhang a,b,a Institute of Marine Biotechnology,Department of Biological sciences and Biotechnology,{3. University,beijing 100084,China b Protein science laboratory of the Ministry of Education,{3. University,beijing 100084,China Institute of Marine Biotechnology Department of Biological Sciences and Biotechnology Tsinghua University Beijing 100084 China Protein science laboratory of the Ministry of Education Tsinghua University Beijing 100084 China

A 1063.bp cDNA clone encoding a putative 3. kDa laminin receptor precursor (3. kDa LRP) is isolated from the mantle tissue of pearl oyster,Pinctada fucata. The amino acid sequence predicted from the cDNA sequence is 3.1 residues long,with a calculated molec-ular mass of 3..5 kDa. RT-PCR analysis shows that 3. kDa LRP mRNA is especially highly expressed in the mantle while widely expressed in several tissues. In situ hybridization analysis reveals that 3. kDa LRP is expressed in the outer epithelial cells of the mantle edge,suggesting its involvement in cell proliferation and secretion in P. fucata. The identification and characterization of 3. kDa LRP in the pearl oyster will help us to further understand the signal transduction in the processes of mantle epithelial cell proliferation and tissue formation.

关键词： 3. kDa laminin receptor precursor Mantle epithelial cell Pearl oyster

Absence of State Collapse and Revival in a Superconducting Charge Qubit

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Communications in Theoretical Physics 2007年第12期48卷 1029-1032页

作者： HUO Wen-Yi~1 and LONG Gui-Lu~(1,2,3.~1 Department of Physics amd Key laboratory for Quantum information and Measurements,tsinghua University,{3.100084,China~2 Key laboratory for Atomic and Molecular Nanosciences,tsinghua University,beijing 100084,China~3.national laboratory for information science and {13.,Hsinghua University,beijing 100084,China Department of Physics amd Key laboratory for Quantum information and Measurements Tsinghua University Key laboratory for Atomic and Molecular Nanosciences Tsinghua University national laboratory for information {3. and technology Hsinghua Univers

The Hamiltonian of a superconducting charge qubit with a configuration of dc SQUID contains an interac-tion between the LC oscillator part and charge *** interaction may leads to quantum state collapse and revivalwhich degrades the charge qubits and leads to serious *** analysis shows that the existing charge qubitparameters do not lead to this phenomenon,which is very good for the superconducting charge

关键词： quantum computer superconducting charge qubit absence and revival

Preparation of nanocrystalline BaTiO_3.ceramics

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science China(Technological sciences) 2009年第6期52卷 1730-1734页

作者： DENG XiangYun1,2,LI DeJun1,LI JianBao2,WANG XiaoHui3.& LI LongTu3.1 College of Physics and Electronic information,Tianjin Normal University,Tianjin 3.03.7,China 2 Materials and Chemical Engineering Institute,Key laboratory for Hainan Advantage Resources and Applied technology in Chemical Engineering Material of Ministry of Education,Hainan Provincial Key laboratory of Research on Utilization of Si-Zr-Ti,Hainan University,Haikou 570228,China 3.Department of Materials science and Engineering,tsinghua University,beijing 100084,China College of Physics and Electronic information Tianjin Normal University Tianjin 300387 China Materials and Chemical Engineering Institute Key Laboratory for Hainan Advantage Resources and Applied Technology in Chemical Engineering Material of Ministry of Education Hainan Provincial Key Laboratory of Research on Utilization of Si-Zr-Ti Hainan University Haikou 570228 China Department of Materials science and Engineering Tsinghua University Beijing 100084 China

The high-dense nanocrystalline BaTiO3.BT)ceramics with grain size smaller than 100nm have been successfully prepared by the two step sintering and the spark plasma sintering(SPS)*** successive transitions in nanograin BT ceramics from rhombohedral to orthorhombic,tetragonal and cubic transitions,similar to those in coarse BT ceramics,were revealed by in-situ temperature dependent Raman *** multiphase coexistence and the diffused phase transition character were demonstrated in the 8nm nanocrystalline BT ceramics.

关键词： nanocrystalline BaTiO3 ceramics preparation microstructure size effect

Cloning and characterization of cotton heteromeric acetyl-CoA carboxylase genes

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Progress in Natural science:Materials International 2007年第12期17卷 1412-1418页

作者： Qiao Zhixin and Liu Jinyuan(laboratory of Molecular Biology and Protein science laboratory of the Ministry of Education, Department of Biological sciences and Biotechnology, tsinghua University, beijing 100084, China) laboratory of Molecular Biology and Protein science laboratory of the Ministry of Education Department of Biological Sciences and Biotechnology Tsinghua University Beijing 100084 China

Heteromeric acetyl-coenzyme A (CoA) carboxylase (ACCase) catalyzes the formation of malonyl-CoA from acetyl-CoA. It plays an essential role in fatty acid synthesis in prokaryotes and most of plants. The heteromeric ACCase is composed of four subunits: biotin carboxylase (BC), biotin carboxyl carrier protein (BCCP), and α- and β-subunits of carboxyltransferase (α- and β-CT). In this study, we cloned five novel genes encoding the subunits of heteromeric ACCase (one BC, BCCP and β-CT, and two α-CTs) from cotton (Gossypium hirsutum cv. zhongmian 3.) by RACE-PCR. The deduced amino acid sequence of these cDNAs shares high similarity with other reported heteromeric ACCase subunits. The phylogenetic analysis indicated that the different subunits of heteromeric ACCase were grouped in a similar pattern. Southern blot analysis revealed the milti-copy patterns of these heteromeric ACCase genes in cotton genome. Semi-quantitative RT-PCR demonstrated that heteromeric ACCase genes were constitutively expressed in all of the cotton tissues, but the transcripts accumulated at a relatively low level in roots. To our knowledge, this is the first report about characterization of the heteromeric ACCase genes in cotton.

关键词： heteromeric ACCase cotton gene cloning fatty acid synthesis.

Fuzzy dynamic characteristic modeling and adaptive control of nonlinear systems and its application to hypersonic vehicles

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science China(information sciences) 2011年第3期54卷 460-468页

作者： LI HongBo , SUN ZengQi, MIN HaiBo & DENG JianQiu Department of Computer science and technology, tsinghua University, {3., China 1. Department of Computer science and technology Tsinghua University Beijing 100084 China

In this paper, a fuzzy dynamic characteristic modeling and adaptive control method is proposed for a class of nonlinear systems. By employing fuzzy dynamic characteristic model, the controlled plant is described as a slowly time-varying fuzzy system, wherein the parameters are estimated online by using recursive Least-Squares algorithm. Under this framework, a fuzzy adaptive controller is constructed, and the stability condition of the closed-loop system is also derived. The main advantage of the proposed method lies in no requirement for the prior knowledge of system model and less parameters to tune, which allows engineers to operate it in a simple, straightforward manner. The proposed method is applied to the control of hypersonic vehicle, and simulation results are given to demonstrate the effectiveness of the obtained results.

关键词： fuzzy control dynamic characteristic model adaptive control hypersonic vehicle

Black-box testing based on colorful taint analysis

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science China(information sciences) 2012年第1期55卷 171-183页

作者： CHEN Kai1,2,3.FENG DengGuo1,SU PuRui1&ZHANG YingJun1,2,3.1State Key laboratory of information Security,Institute of Software,Chinese Academy of science,{3. 100190,China 2State Key laboratory of information Security,Graduate University of Chinese Academy of sciences,{3. 100049,China 3.8} Engineering Research Center of information Security,{3. 100190,China 1. State Key laboratory of information Security Institute of Software Chinese Academy of Science Beijing 100190 China2. State Key Laboratory of Information Security Graduate University of Chinese Academy of Sciences Beijing 100049 China3. National Engineering Research Center of Information Security Beijing 100190 China

Software vulnerability detection is one of the most important methods for guaranteeing software *** main classes of methods can detect vulnerabilities in binary files:white-box testing and black-box *** former needs to construct and solve path constraints to detect *** has two main drawbacks:path exploding and complexity of *** latter often aimlessly exhausts various inputs to test binary *** paper combines both testing methods to detect vulnerabilities in binary *** analyzing the input elements that aect check condition corresponding to a certain check point,we can generate one class of inputs that get to the check point to increase fuzzing *** analyzing the relationship between guard conditions and check condition,the redundant check points are *** taint analysis method(CTAM)is proposed to compute guard conditions,which is more ecient than traditional taint analysis method(TTAM).We implemented a prototype and made several experiments on *** results showed that our method could increase the eciency of black-box testing.

关键词： software testing vulnerability detection dynamic testing black-box testing colorful taint analysis

ADAPTIVE VARIABLE STRUCTURE CONTROLLERS AND APPLICATION TO ENGINE IDLE SPEED CONTROL SIMULATION

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Chinese Journal of Mechanical Engineering 2003年第2期16卷 171-174页

作者： Hui Qing Quyang MinggaoState Key laboratory of AutomotiveSafety and Energy,tsinghua University,beijing 100084, China State Key laboratory of Automotive Safety and Energy Tsinghua University Beijing 100084 China

A neural-network-based adaptive variable structure control methodology isproposed for the tracking problem of nonlinear discrete-time input-output systems. The unknowndynamics of the system are approximated via radial basis function neural networks. The control lawis based on sliding modes and simple to implement. The discrete-time adaptive law for tuning theweight of neural networks is presented using the adaptive filtering algorithm with residueupper-bound compensation. The application of the proposed controller to engine idle speed controldesign is discussed. The results indicate the validation and effectiveness of this approach.

关键词： variable structure control adaptive control neural networks nonlineardiscrete-time systems idle speed control