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The localization of 1-cohomology of transitive Lie algebroids

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science china Mathematics 2006年第2期49卷 277-288页

作者： CHEN Zhuo & LIU Zhangju Department of Mathematics, Capital normal university, beijing 100037, china School of Mathematical science, Peking university, beijing 100871, china 1. Department of Mathematics Capital Normal University Beijing 100037 China 2. School of Mathematical science Peking University Beijing 100871 China

For a transitive Lie algebroid A on a connected manifold M and its representation on a vector bundle F, we define a morphism of cohomology groups rk: Hk(A,F) → Hk(Lx,Fx), called the localization map, where Lx is the adjoint algebra at x ∈ M. The main result in this paper is that if M is simply connected, or H (LX,FX) is trivial, then T is injective. This means that the Lie algebroid 1-cohomology is totally determined by the 1-cohomology of its adjoint Lie algebra in the above two cases.

关键词： transitive Lie algebroid representation cohomology localization.

New fossil ommatid (Coleoptera:Archostemata:Ommatidae) from Jehol Biota of western Liaoning, china

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Progress in Natural science:Materials International 2006年第6期16卷 639-643页

作者： REN Dong, TAN Jingjing and GE Siqin (college of Life science, Capital normal university, beijing 100037, china Institute of Zoology, Chinese Academy of sciences, beijing 100080, china) [a]college of Life science Capital Normal University Beijing China [b]Institute of Zoology Chinese Academy of Sciences Beijing China

In this paper one new genus and one new species of fossil ommatid, Odontomma trachylaena gen. et sp. nov., is described and illustrated from the Late Jurassic or Early Cretaceous Yixian Formation of western Liaoning, china. Based on wide epipleural space of elytron with several rows of cells, the new taxa is attributed to tribe Brochocoleini of Ommatidae and compared with genus Bro-chocoleus. Due to the fact that most other Chinese Mesozoic ommatids are not complete, the complete preservation of the new specimens reported here enabled us to determine the characteristics of the body of these ancient ommatid. Moreover, based on the well-preserved individual of this new genus, we may suppose the affinities of the new species with extant and extinct groups.

关键词： Ommatidae Late Jurassic Early Cretaceous Liaoning Province.

Threshold quantum secure direct communication without entanglement

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science china(Physics,Mechanics & Astronomy) 2008年第2期51卷 176-183页

作者： YANG YuGuang1,3 & WEN QiaoYan2 1 college of Computer science and Technology, beijing university of Technology, beijing 100022, china 2 School of science, beijing university of Posts and Telecommunications, beijing 100876, china 3 State Key Laboratory of Information Security (Graduate School of Chinese Academy of sciences), beijing 100049, china 1. college of Computer science and Technology Beijing University of Technology Beijing 100022 China 3. State Key Laboratory of Information Security (Graduate School of Chinese Academy of sciences) Beijing 100049 China 2. School of science Beijing University of Posts and Telecommunications Beijing 100876 China

For the first time, a threshold quantum secure direct communication (TQSDC) scheme is presented. Similar to the classical Shamir's secret sharing scheme, the sender makes n shares, S1, …, Sn of secret key K and each receiver keeps a share secretly. If the sender wants to send a secret message M to the receivers, he en-codes the information of K and M on a single photon sequence and sends it to one of the receivers. According to the secret shares, the t receivers sequentially per-form the corresponding unitary operations on the single photon sequence and ob-tain the secret message M. The shared shares may be reusable if it can be judged that there is no eavesdropper in line. We discuss that our protocol is feasible with current technology.

关键词： quantum secure direct communication threshold secure direct communication quantum secret sharing

Implementation of a multiple round quantum dense coding using nuclear magnetic resonance

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science china(Physics,Mechanics & Astronomy) 2005年第6期48卷 706-715页

作者： ZHANG Jingfu1, XIE Jingyi2, WANG Chuan1, DENG Zhiwei3, LU Zhiheng4, & LONG Guilu1,5 1. Key Laboratory For Quantum Information and Measurements of MOE, Department of Physics, Tsinghua university, beijing 100084,china 2. Department of Materials science and Engineering, beijing normal university, beijing 100875, china 3. Testing and Analytical Center, beijing normal university, beijing 100875,china 4. Department of Physics, beijing normal university, beijing 100875, china 5. Key Laboratory For atomic and Molecular Nanosciences, Tsinghua university, beijing 100084,china 1. Key Laboratory For Quantum Information and Measurements of MOE Department of Physics Tsinghua University 100084 Beijing China 2. Department of Materials science and Engineering Beijing Normal University 100875 Beijing China 3. Testing and Analytical Center Beijing Normal University 100875 Beijing China 4. Department of Physics Beijing Normal University 100875 Beijing China 5. Key Laboratory For Atomic and Molecular Nanosciences Tsinghua University 100084 Beijing China

A multiple round quantum dense coding scheme based on the quantum phase estimation algorithm is proposed and implemented in a three qubit nuclear magnetic resonance (NMR) quantum computer. Using an m + 1 qubit system, Bob can transmit one of 2m+1 messages to Alice, through manipulating only one qubit and exchanging it between Alice and Bob for m rounds. The information capacity is enhanced to m + 1 bits as compared to m bits in a classical scheme. The scheme has been demonstrated in NMR system, and the experimental results show a good agreement between theory and experiment.

关键词： quantum dense coding, multiple round, nuclear magnetic resorance

Isolation, characterization and functional analysis of a cdc48 homologue from tobacco BY-2 cells

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Progress in Natural science:Materials International 2007年第2期17卷 156-162页

作者： CHEN Zhiling, YU Yi, LIU Lina and XIA Guixian ( college of Life science, Capital normal university, beijing 100037, china Institute of Microbiology, Chinese Academy of sciences, beijing 100080, china) [a]college of Life science Capital Normal University Beijing China [b]Institute of Microbiology Chinese Academy of Sciences Beijing China

The fission yeast Schizosaccharomyces pombe was used to identify genes from tobacco BY-2 cells that may play roles in cell cycle regulation. A cDNA encoding a protein homologous to the yeast CDC48 was isolated and the gene was designated as NtCDC48 . The cDNA contains an open reading frame coding for a predicted protein of 808 amino acids which comprises of two typical ATPase modules (aa 245-374 and aa 518-646) . Overexpression of NtCDC48 in tobacco BY-2 cells led to an increase in the mitotic index as well as to the formation of diffused mitotic spindles. NtCDC48-GFP fusion proteins are distributed ubiquitously through Gl to M phases, yet their subcellular localization varied regularly along with the cell cycle progression. These results indicate that NtCDC48 may play an important role in the regulation of cell cycle in BY-2 cells.

关键词： tobacco BY-2 suspension cells NtCDC48 spindle cell cycle.

Functional central limit theorem for super α-stable processes

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science china Mathematics 2004年第6期47卷 874-881页

作者： HONG WenmingDepartment of Mathematics, beijing normal university, beijing 100875, china 1. Department of Mathematics Beijing Normal University 100875 Beijing China

A functional central limit theorem is proved for the centered occupation time process of the super α-stable processes in the finite dimensional distribution sense. For the intermediate dimensions α < d < 2α (0 < α ≤ 2), the limiting process is a Gaussian process, whose covariance is specified; for the critical dimension d= 2α and higher dimensions d < 2α, the limiting process is Brownian motion.

关键词： super α-stable processes occupation time central limit theorem evolution equation

A new class of impulse stochastic control models with non-negative control quantity

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science china(Information sciences) 2011年第3期54卷 638-652页

作者： LIU XiaoPeng & LIU KunHui college of science, beijing Jiaotong university, beijing 100044, china 1. college of science Beijing Jiaotong University Beijing 100044 China

This paper advances and studies a new class of impulse stochastic control models. Its state structure is defined by a linear stochastic differential equation of the semi-martingale, its control cost function is a twovariable function of pre-control state quantity and control quantity, and its control quantity is kept non-negative. First this paper constructs a new type of variational equations and proves its solution exists. Using a series of stochastic analysis methods to research the solution function of this type of variational equations, this paper proves the existence of optimal control and analyzes its structure in depth. Because of the big difference between the model in this paper and stochastic control models in previous papers, the analysis method here is quite different from previous ones. It is expected that this paper will have important theoretical significance for stochastic control research, along with wide applicative value in finance control and security management.

关键词： impulse stochastic control control quantity variational equation optimal control semi-martingale

Theorems for Testing Local Activity of CNN and Application to Cardiac Purkinje Equations

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International Journal of Minerals,Metallurgy and Materials 2000年第2期14卷 139-146页

作者： Lequan Min(Applied science School, university of science and Technology beijing, beijing 100083, china) Applied science School University of Science and Technology Beijing Beijing 100083 China

The theorems for testing the local in one-port cellular neural/inear network (CNN) cells with four local state variables are presented. Using the theorems computes the bifurcation diagrams of the cardiac Purkinje fiber (CPE) equations Which describethe long-lasting action and pace-maker potentials of the Purkinje fiber of the heart. The computer simulation shows that periodic trajectories or convergent trajectories of the CPF Equations can be foun if the cormsponing cell Parameters are located in a positive domainbut nearby edge of chaos. In particular a heart with approximate normal frequency of heartbeat but non-normal electrocardiogram maysuddenly stop by slightly perturbing the parameters of the corresponding CPF Equations when the Paramders are located nearby the edge of chaos in the bifurcation diagrams. This research seems to interpret reasonbly the phenomena that patients with cardiac diseases might suddenly die without warning.

关键词： cellular neural network local activity cardiac Purkinje fiber heartbeat

A heuristic path-estimating algorithm for large-scale real-time traffic information calculating

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science china(Technological sciences) 2008年第S1期51卷 165-174页

作者： L WeiFeng1,ZHU TongYu1,WU DongDong2,DAI Hong3 & HUANG Jian1 1 State Key Laboratory for Software Development Environment,Beihang university,beijing 100083,china 2 beijing Transportation Information Center,beijing 100055,china 3.college of Arts & science,beijing Union university,beijing 100083,china 1. State Key Laboratory for Software Development Environment Beihang University Beijing 100083 China 2. beijing Transportation Information Center Beijing 100055 China 3. college of Arts & science Beijing Union University Beijing 100083 China

As the original Global Position System (GPS) data in Floating Car Data have the accuracy problem,this paper proposes a heuristic path-estimating algorithm for large-scale real-time traffic information calculating. It uses the heuristic search method,imports the restriction with geometric operation,and makes comparison between the vectors composed of the vehicular GPS points and the special road network model to search the set of vehicular traveling route candidates. Finally,it chooses the most optimal one according to weight. Experimental results indicate that the algorithm has considerable efficiency in accuracy (over 92.7%) and com-putational speed (max 8000 GPS records per second) when handling the GPS tracking data whose sampling rate is larger than 1 min even under complex road network conditions.

关键词： path-estimating floating car data (FCD) road network vector GPS