检索结果-南通市图书馆

Threshold proxy quantum signature scheme with threshold shared verification

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science China(Physics,Mechanics & Astronomy) 2008年第8期51卷 1079-1088页

作者： YANG YuGuang1,3,4 & WEN QiaoYan2 1 College of Computer Science and Technology,beijing University of Technology,beijing 100124,China 2 State Key Laboratory of Networking and Switching Technology,beijing University of Posts and Tele-communications,beijing 100876,China 3 State Key Laboratory of Integrated Services Network,Xidian University,Xi’an 710071,China 4 State Key Laboratory of Information Security(Graduate University of Chinese Academy of Sciences) ,beijing 100049,China College of Computer Science and Technology Beijing University of Technology Beijing China State Key Laboratory of Integrated Services Network Xidian University Xi’an China State Key Laboratory of Information Security (Graduate University of Chinese Academy of Sciences) Beijing China State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing China

A threshold proxy quantum signature scheme with threshold shared verification is proposed. An original signer could authorize a group as its proxy signers. Then only t or more of n persons in the proxy group can generate the proxy signature on behalf of the original signer and any t-1 or fewer ones cannot do that. When the proxy signature needs to be verified,any t or more of n persons belonging to the verification group can verify the message and any t-1 or fewer ones cannot verify the validity of the proxy signature.

关键词： quantum signature threshold proxy quantum group signature threshold shared verification

Differentiation transforming system

在线全文

学校读者我要写书评

暂无评论

Progress in Natural Science:Materials International 2009年第3期19卷 397-406页

作者： Qiang Chenga,b,c,*, Haibin Zhang d, Bin Wanga, Yonghua Zhao c a LASG, Institute of Atmospheric Physics, Chinese Academy of Sciences, beijing 100029, PR China b LSEC, Institute of Computing Mathematics, Chinese Academy of Sciences, beijing 100080, PR China c SC, Institute of Computer Network Information Center, Chinese Academy of Sciences, beijing 100190, PR China d College of Applied Sciences, beijing University of Technology, beijing 100124, PR China LASG Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 PR China LSEC Institute of Computing Mathematics Chinese Academy of Sciences Beijing 100080 PR China SC Institute of Computer Network Information Center Chinese Academy of Sciences Beijing 100190 PR China College of Applied Sciences Beijing University of Technology Beijing 100124 PR China

The differentiation transforming (DFT) system is developed to produce the tangent linear codes, which is used to calculate the Jaco- bian- and the Hessian-vector products with no truncation errors. This paper first gives the introduction of the functionality and features of the DFT system, and then discusses several techniques for the implementation of automatic differentiation tools, including data depen- dence analysis, singular differentiation and code optimization. Finally, the codes generated with DFT used in several applications have been demonstrated.

关键词： Jacobian Hessian Tangent linear model Automatic differentiation

SMOOTH CLASSIFICATION AND LINEARIZATION OF HYPERBOLIC VECTOR FIELDS ON R^3

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Annals of Differential Equations 2009年第3期25卷 343-347页

作者： Zhihua Ren (Dept. of Applied Math.,beijing University of Technology,beijing 100124 Dept.of Applied Math. Beijing University of TechnologyBeijing 100124

This paper is devoted to studying smooth normal form theory of hyperbolic vector fields. As a continuation of our previous work on smooth classification and linearization of vector fields near a hyperbolic singular point,in this paper,we deal with the case of hyperbolic vector fields on R3 by examining all possible resonant classes.

关键词： vector fields resonance smooth classification normal form

Young tableaux and crystal base for Uq(osp（1|2n）)

在线全文

学校读者我要写书评

暂无评论

Science China Mathematics 2010年第2期 291-305页

作者： LIU JunLi & YANG ShiLin College of Applied Sciences, beijing University of Technology, beijing 100124, China

Let Uq(osp(1|2n)) be the quantized enveloping superalgebra corresponding to the Lie superalgebra osp(1|2n). In terms of semistandard Young tableaux satisfying some additional conditions, a realization of crystal graph of finite-dimensional irreducible modules of Uq(osp(1|2n)) is given. Also, the generalized LittlewoodRichardson rule for tensor product of crystal graphs is established.

关键词： quantum group crystal base young diagram Young tableaux

A fast stereoscopic video coding algorithm based on JMVM

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science China(Information Sciences) 2011年第6期54卷 1218-1226页

作者： DENG ZhiPin 1,2 , JIA KeBin 1 , CHAN YuiLam 2 , FU ChangHong 2 & SIU WanChi 2 1 Department of Electronic Information & Control Engineering, beijing University of Technology, beijing 100124, China 2 Department of Electronic Information Engineering, Hong Kong Polytechnic University, Hong Kong, China Department of Electronic Information & Control Engineering Beijing University of Technology Beijing China Department of Electronic Information Engineering Hong Kong Polytechnic University Hong Kong China

In order to exploit the intra-view and inter-view dependencies in stereo video coding, a fast joint motion and disparity estimation algorithm is proposed in this paper. An efficient search strategy based on the motion-disparity constraint is developed, in which both the motion and disparity vectors can be obtained simultaneously with low complexity. Moreover, a credible initial predictive vector set is designed with the aid of the temporal and spatial neighboring blocks so that the coding efficiency can be further enhanced. The experimental results demonstrate that the proposed algorithm can reduce more than 96% coding time compared with the JMVM full search with a negligible quality drop.

关键词： H.264 stereoscopic video coding disparity estimation motion estimation

Systematic study of survival probability of excited superheavy nuclei

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science China(Physics,Mechanics & Astronomy) 2011年第S1期54卷 109-113页

作者： XIA ChengJun1, SUN BaoXi1, ZHAO EnGuang2,3 & ZHOU ShanGui2,3 1College of Applied Sciences, beijing University of Technology, beijing 100124, China 2Institute of Theoretical Physics, Chinese Academy of Sciences, beijing 100190, China 3Center of Theoretical Nuclear Physics, National Laboratory of Heavy Ion Accelerator, Lanzhou 730000, China College of Applied Sciences Beijing University of Technology Beijing China Institute of Theoretical Physics Chinese Academy of Sciences Beijing China Center of Theoretical Nuclear Physics National Laboratory of Heavy Ion Accelerator Lanzhou China

The stability of excited superheavy nuclei (SHN) with 100 Z 134 against neutron emission and fission is investigated by using a statistical model. In particular, a systematic study of the survival probability against fission in the 1n-channel of these SHN is made. The present calculations consistently take the neutron separation energies and shell correction energies from the calculated results of the finite range droplet model which predicts an island of stability of SHN around Z = 115 and N = 179. It turns out that this island of stability persists for excited SHN in the sense that the calculated survival probabilities in the 1n-channel of excited SHN at the optimal excitation energy are maximized around Z = 115 and N = 179. This indicates that the survival probability in the 1n-channel is mainly determined by the nuclear shell effects.

关键词： survival probability superheavy elements island of stability neutron emission fission

Molecular dynamics simulation of the transmembrane subunit of BtuCD in the lipid bilayer

在线全文

学校读者我要写书评

暂无评论

Science China(Life Sciences) 2010年第5期53卷 620-630页

作者： SUN TingGuang1,2,LIU Ming1,CHEN WeiZu1 & WANG CunXin1 1College of Life Science and Bioengineering,beijing University of Technology,beijing 100124,China 2Department of Biological and Chemical Engineering,Guangxi University of Technology,Liuzhou 545006,China College of Life Science and Bioengineering Beijing University of Technology Beijing China Department of Biological and Chemical Engineering Guangxi University of Technology Liuzhou China

Based on the crystal structure of the vitamin B12 transporter protein of Escherichia coli(BtuCD) a system consisting of the BtuCD transmembrane domain(BtuC) and the palmitoyloleoyl phosphatidylcholine(POPC) lipid bilayer was constructed in silica,and a more-than-57-nanosecond molecular dynamics(MD) simulation was performed on it to reveal the intrinsic functional motions of *** results showed that a stable protein-lipid bilayer was obtained and the POPC lipid bilayer was able to adjust its thickness to match the embedded BtuC which underwent relatively complicated *** results may help to understand the mechanism of transmembrane substrate transport at the atomic level.

关键词： BtuCD POPC functional motion principal component analysis

Improvement in the Oxidation Resistance of Tungsten by Sol-Gel Derived Al_2O_3 Coating

在线全文

学校读者我要写书评

暂无评论

稀有金属材料与工程 2012年第S1期41卷 303-305页

作者： Fan Ailing1,Meng Lingsheng1,Huang Lang1,2,Ma Jie1 1 College of Materials Science and Engineering,beijing University of Technology,beijing 100124,China 2 Department of Safety and Environment,Xinyu Iron&Steel Group Co.Ltd,Xinyu 338001,China beijing Univ Technol Coll Mat Sci & Engn Beijing 100124 Peoples R China Xinyu Iron & Steel Grp Co Ltd Dept Safety & Environm Xinyu 338001 Peoples R China

An Al2O3 coating was prepared from aluminum isopropoxide as precursor on tungsten *** dependences of crystalline and phase in Al2O3 coating on temperature were *** results show the coatings being compact,uniform and crack-free can be obtained by suitable *** main phase of coating is α-*** to the uncoated specimens,the ones with coatings synthesized by sol-gel process provide excellent oxidation resistance at high temperature.

关键词： sol-gel process tungsten filament Al2O3 coating

A Note on Shift-Invariant Spaces Admitting a Single Generator

在线全文

学校读者我要写书评

暂无评论

Journal of Mathematical Research and Exposition 2011年第1期31卷 123-128页

作者： Jun Jian ZHAO1,21.Department of Mathematics,Tianjin Polytechnic University,Tianjin 300160,P.R.China 2.College of Applied Sciences,beijing University of Technology,beijing 100124,P.R.China Department of Mathematics Tianjin Polytechnic University Tianjin 300160

In 2005, Garcia, Perez-Villala and Portal gave the regular and irregular sampling formulas in shift invariant space Vφ via a linear operator T between L^2（0, 1） and L^2（R）. In this paper, in terms of bases for L^... 详细信息

关键词： shift-invariant spaces sampling Riesz bases.