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Dense coding scheme using superpositions of Bell-states and its NMR implementation

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Science china(Physics,Mechanics & Astronomy) 2005年第1期48卷 57-67页

作者： ZHANG Jingfu, XIE Jingyi, DENG Zhiwei & LU Zhiheng Key Laboratory for Quantum Information and Measurements, Department of Physics, Tsinghua University, beijing 100084, china {2. for Quantum Information, Tsinghua University, beijing 100084, china Department of Materials Science and Engineering, beijing Normal University, beijing 100875, china testing and analytical {2., beijing Normal University, beijing 100875, china Department of Physics, beijing Normal University, beijing 100875, china Key Laboratory for Quantum Information and Measurements Department of Physics Tsinghua University Beijing 100084 China center for Quantum Information Tsinghua University Beijing 100084 China Department of Materials Science and Engineering Beijing 100875 China testing and analytical {2. Beijing Normal University Beijing 100875 China Department of Physics Beijing Normal University Beijing 100875 China

Dense coding using superpositions of Bell-states is proposed. The generalized Grover's algorithm is used to prepare the initial entangled states, and the reverse process of the quantum algorithm is used to determine the entangled state in the decoding measurement. Compared with the previous schemes, the superpositions of two Bell-states are exploited. Our scheme is demonstrated using a nuclear magnetic resonance (NMR)quantum computer. The corresponding manipulations are obtained. Experimental results show a good agreement between theory and experiment. We also generalize the scheme to transmit eight messages by introducing an additional two-state system.

关键词： dense coding, superpositions of Bell-states, generalized Grover's algorithm, nuclear magnetic res-onance, quantum computer.

The study of two-color excitation upconversion of Pr(0.5)Yb(3.:ZBLAN

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Science china(Physics,Mechanics & Astronomy) 2006年第2期49卷 169-177页

作者： CHEN Xiaobo1 & SONG Zengfu2.1. Applied Optics beijing Area Major Laboratory, Analysis and testing {2., beijing Normal University, beijing 100875, china 2. Peking University, Physics School, beijing 100871, china Applied Optics beijing Area Major Laboratory Analysis and testing center Beijing Normal University Beijing China Physics School Peking University Beijing China

The excited state absorption upconversion of Pr(0.5)Yb(3.:ZBLAN glass material, under two-color excitation of the 960 nm semiconductor laser and the Xe lamp light simultaneously, is reported in this article. It was found that the upconversion emission spectra of 480.1, 519.0, 601.9 and 63..8 nm coincide with the common emission spectra. Meanwhile, the upconversion-excitation spectrum has three obvious peaks under two-color excitation, and they respectively correspond to the 856.0 nm upconversion ex-citation transition [1G4(Pr3.)→1I6(Pr3.) and 1G4(Pr3.)→3.1(Pr3.)], the 789.0 nm upconver-sion excitation transition 1G4(Pr3.)→3.2.Pr3.), and the 803.7 nm upconversion excitation transition 3.6(Pr3.)→1D2.Pr3.). The upconversion excitation transition 1G4(Pr3.)→1I6(Pr3.) is strong because its oscillator strength f = 2.0}040×10?6 is large, which results in a large peak appearing in the upconversion excitation spectrum. That is just the new interesting two-color excitation upconversion luminescence phenomenon of Pr(0.5)Yb(3.:ZBLAN induced by one laser and one continuous normal light simultaneously.

关键词： upconversion volumetric three-dimensional display two-color excitation.

Re-Os(ICP-MS)dating of the massive sulfide ores from the Jinchuan Ni-Cu-PGE deposit

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Science china Earth Sciences 2005年第10期48卷 1672-1677页

作者： YANG Gang1,2. DU Andao1, LU Jiren3. QU Wenjun1 & CHEN Jiangfeng2.1. National Research center of Geoanalysis, {2. 10003., china 2. Laboratory for Earth Material Cycling, School of Earth and Space Sciences, University of Science and Technology of china, Hefei 2.0}02., china 3. Institute of Mineral Resource, Chinese Academy of Geological Sciences, {2. 10003., china National Research center of Geoanalysis University of Science and Technology of china Chinese Academy of Geological Sciences

Massive sulfide ore from the Jinchuan Ni-Cu-PGE deposit was dated by Re-Os technique using Carius Tube digestion, Os distillation, Re extraction by acetone and ICP-MS measurement. An isochron giving an age of 83. ± 3. Ma, initial 187Os/188Os ratio of 0.2.9 ± 0.018 (MSWD = 1.7) and γOs = 13. ± 15 is obtained. The Re-Os age obtained agrees, within analytical uncertainties, with previous SHRIMP zircon U-Pb age of 82. ± 8 Ma (n=5, MSWD = 4.3.. The result suggests that the deposit was formed at Neoproterozoic and that the formation of the Jinchuan Ni-Cu-PGE sulfide deposit may be closely related to the plume activity, which were attributed to the breakup of the Rodinia supercontinent. The high γOs of the massive ores sug-gests that crustal material was involved in the formation of the Jinchuan deposit, however, the quantity of the added crustal material is less than 10%.

关键词： Jinchuan Ni-Cu-PGE deposit, Re-Os dating, ICP-MS.

Representation of microscale ocean wavenumber spectrum correct to the second order

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Science china Earth Sciences 2005年第4期48卷 549-554页

作者： YUAN Yeli2.& HUA Feng1,2.3.1. Institute of Oceanology, Chinese Academy of Sciences, Qingdao 2.6071, china 2. Key Laboratory of Marine Science and Numerical Modeling, State Oceanic Administration, Qingdao 2.6061, china 3. Graduate School of the Chinese Academy of Sciences, beijing 10003., china Key Laboratory of Marine Science and Numerical Modeling State Oceanic Administration Qingdao China Institute of Oceanology Chinese Academy of Sciences Qingdao China Graduate School of the Chinese Academy of Sciences Beijing China

In this paper, the analytical representations of four wave source functions in high-frequency spectrum range are given on the basis of ocean wave theory and dimensional analysis, and the perturbation method is used to solve the governing equations of ocean wave high-frequency spectrum on the basis of the temporally stationary and locally homogeneous scale relations of microscale wave. The microscale ocean wavenumber spectrum correct to the second order has an explicit structure, its first order part represents the equilibrium between dif- ferent source functions, and its second order part represents the contribution of microscale wave propagation.

关键词： temporally stationary and locally homogeneous, source function in high-frequency spectrum range, microscale ocean wavenumber spectrum.

A formal method to real-time protocol interoperability testing

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Science in china(Series F) 2008年第11期51卷 1723-1744页

作者： WANG ZhiLiang1,3.YIN Xia2.3.& JING ChuanMing2.3.1 Network Research center,Tsinghua University,beijing 100084,china 2.Department of Computer Science and Technology,Tsinghua University,beijing 100084,china 3.Tsinghua National Laboratory for Information Science and Technology(TNList) ,beijing 100084,china Network Research center Tsinghua University Beijing China Tsinghua National Laboratory for Information Science and Technology (TNList) Beijing China Department of Computer Science and Technology Tsinghua University Beijing China

Interoperability testing is an important technique to ensure the quality of implementations of network communication protocol. In the next generation Internet protocol, real-time applications should be supported effectively. However, time constraints were not considered in the related studies of protocol interoperability testing, so existing interoperability testing methods are difficult to be applied in real-time protocol interoperability testing. In this paper, a formal method to real-time protocol interoperability testing is proposed. Firstly, a formal model CMpTIOA （communicating multi-port timed input output automata） is defined to specify the system under test （SUT） in real-time protocol interoperability testing; based on this model, timed interoperability relation is then defined. In order to check this relation, a test generation method is presented to generate a parameterized test behavior tree from SUT model; a mechanism of executability pre-determination is also integrated in the test generation method to alleviate state space explosion problem to some extent. The proposed theory and method are then applied in interoperability testing of IPv6 neighbor discovery protocol to show the feasibility of this method.

关键词： protocol testing interoperability testing real-time testing test generation timed input output automata(TIOA)

Mechanisms of invasive population establishment and spread of pinewood nematodes in china

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Science china(Life Sciences) 2009年第6期52卷 587-594页

作者： XIE BingYan1,CHENG XinYue2.SHI Juan3.ZHANG QingWen4,DAI ShuMing1,CHENG Fei Xue2.& LUO YouQing3.1 Institute of Vegetables and Flowers,Chinese Academy of Agricultural Sciences,{2. 100081,china 2.{2. Normal University,{2. 100875,china 3.{2. Forestry University,{2. 100083.china 4 Chinese Agricultural University,{2. 100094,china Institute of Vegetables and Flowers Chinese Academy of Agricultural Sciences Beijing China beijing Normal University Beijing China beijing Forestry University Beijing China Chinese Agricultural University Beijing China

This paper summarizes the results of our study of the pinewood nematode(Bursaphelenchus xylophi-lus).By population genetic analysis,it was determined that there was no genetic bottle caused by the founder effect and genetic drift in the Chinese invasive *** invasions with large amounts of nematodes from different sources led to rich genetic diversity in the invasive *** high genetic diversity in the invasive process may be one of the genetic mechanisms in its successful *** testing interspecies competition,it was shown that,with high fecundity and a strong competitive ability,*** outcompeted the native species *** in the natural ecosystem during the invasion *** displacement may be one of the ecological mechanisms of ***'s *** addition,an unequal interspecific hybridization with intro-gress was in favor of the invasive species which also accelerated the replacement of *** by *** structures,functions and evolutions of a few important genes that are closely related to the ecological adaptation of pinewood nematodes were studied to explore the molecular mechanism of its ecological ***,the resistance and resilience mechanism of the pine ecosystem invaded by pinewood nematodes was also *** results of these studies uncovered a portion of the genetic and ecological mechanisms of PWN's successful invasion and laid a foundation for further study to obtain a comprehensive interpretation of the mechanisms of the nematode *** results also provided a scientific basis for effectively controlling the occurrence and spread of pine wilt disease which is caused by *** aspects requiring further investigation are considered.

关键词： pinewood nematode bioinvasion genetic diversity ecological adaptation resistance resilience

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 Department of Computer Science and Technology Tsinghua University Beijing China Tsinghua National Laboratory for Information Science and Technology (TNList) Beijing China Network Research center Tsinghua University Beijing 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

Physical analysis and numerical simulation for the dynamic behaviour of vehicles in pitching oscillations or rocking motions

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Science china(Technological Sciences) 2007年第4期50卷 385-401页

作者： ZHANG HanXin1,2.3. ZHANG Zhao1,3. YUAN XianXu1,2. LIU Wei1, XIE YuFei1,2.& YE YouDa1,2.1 {2. Aerodynamics Research and Development center, Mianyang 62.000, {2. 2.National Laboratory for Computational Fluid Dynamics, {3. University of Aeronautics and Astronautics, {3. 100083. {2. 3.School of Aerospace, Tsinghua University, {3. 100084, {2. china Aerodynamics Research and Development center Mianyan China National Laboratory for Computational Fluid Dynamics Beijing University of Aeronautics and Astronautics Beijing China School of Aerospace Tsinghua University Beijing China

analytical methods of nonlinear dynamics and numerical simulations for the cou-pling equations of Navier-Stokes and flight mechanics are used to study the dynamic behaviour of pitching motions of reentry capsules with the variation of Mach number, and rocking motions of swept wings with the variation of angle of attack. Conditions under which the dynamic instability, Hopf bifurcation and saddle-node bifurcation occur are obtained. The node-saddle-node topological structure in the phase portrait, i.e. the state of bi-attractors (attracting basins) is described. The evolving process of dynamic behaviour and flow fields are given. The theories are compared with some numerical simulations conducted by the authors. Besides, some verifiable experi-mental results are cited. The agreement between them is very well.

关键词： physical analysis numerical simulation pitching oscillation rocking motion bifurcation

PIXE and INAA studies on ancient potteries from Guangfulin relics in Shanghai

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Progress in Natural Science:Materials International 2007年第11期17卷 1348-1356页

作者： Lin Jiawei1, Cheng Huansheng1, Zhang Zhengquan1, Zhang Bin1, Feng Songlin2. Song Jian3. Gao Menghe4 and Zhu Dan1(1. Applied Ion Beam Physics Laboratory, Key Laboratory of the Ministry of Education, Institute of Modern Physics, Fudan University, Shanghai 2.043., {2. 2. Key Laboratory of Nuclear analytical Techniques, Institute of High Energy Physics, beijing 10003., {2. 3. Shanghai Museum, Shanghai 2.0003. {2. 4. Department of Cultural Heritage and Museology, Fudan University, Shanghai 2.043., {2.) Applied Ion Beam Physics Laboratory Institute of Modern Physics Fudan University Shanghai 200433 China Key Laboratory of Nuclear analytical Techniques Institute of High Energy Physics Beijing 100039 China Shanghai Museum Shanghai 200003 China Department of Cultural Heritage and Museology Fudan University Shanghai 200433 China

This paper reports the study of ancient potteries unearthed from the Guangfulin site in Shanghai. From the external features of these potteries, archeologists can classify them into two different cultural types: Liangzhu culture (local culture) and a new culture which might be derived elsewhere, but they can not recognize whether they were produced in the same place. Proton induced X-ray emission (PIXE) and instrumental neutron activation analysis (INAA) were used to measure the chemical compositions of the samples and the results were analyzed using multivariate statistics. We found that the two methods can complement each other and their database can be mutually referenced in the study of ancient potteries. Experimental results show that the compositions of the potteries from the two cultural types are different, which means that the materials for ancient potteries of new culture originate from elsewhere. This supports the archaeologists’ speculation that a group of ancient people migrated to Shanghai from some other places 4000 years ago.

关键词： PIXE INAA factor analysis Guangfulin ancient pottery