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science.china(Information science.) 2012年第5期55卷 1151-1161页

作者： DONG Lin 1,WANG DaoShun 1,LI ShunDong 2 & DAI YiQi 1 1 department of computer science.and Technology,Tsinghua university,Beijing 100084,china 2 School of computer science.Shaanxi normal university,xi'an 710062,china department of computer science.and Technology Tsinghua University Beijing China School of computer science Shaanxi Normal University Xi’an China

Traditional secret sharing (SS) schemes can reconstruct the secret precisely,but have high com-putation *** secret sharing (VSS) schemes use human visual system to reconstruct the secret without cryptographic computation,but have pixel expansion and loss of *** et *** a (2,n)-SS scheme for binary images based on Boolean operation,which has low computation complexity,no pixel expansion and the contrast is 1/*** this paper,we first construct an r runs (2,n)-SS scheme to improve the contrast of Wang et al.'s binary (2,n)-SS *** we present two approaches to construct r runs (2,n)-SS schemes for grayscale image and color *** two approaches are both based on Boolean operation,while one approach uses halftone technology and the other uses bit level *** proposed schemes have low computation complexity and almost ideal contrast.

关键词： secret sharing scheme Boolean operation halftone contrast

Finite automata based on quantum logic and monadic second-order quantum logic

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science.china(Information science.) 2010年第1期53卷 101-114页

作者： LI YongMing College of computer science. Shaanxi normal university, xi’an 710062, china College of computer science Shaanxi Normal University Xi’an China

We introduce monadic second-order quantum logic and prove that the behaviors of finite automata based on quantum logic are precisely the quantum languages definable with sentences of our monadic secondorder quantum logic. This generalizes Büchi’s and Elgot’s fundamental theorems to quantum logic setting. We also consider first-order quantum logic and show that star-free quantum languages and aperiodic quantum languages introduced here coincide with the first-order quantum definable ones. This generalizes Schützenberger’s fundamental theorems to quantum logic setting. The determinazation of finite automata based on quantum logic is studied by introducing the generalized subset construction method. Then the Kleene theorem in the frame of quantum logic is presented here.

关键词： quantum logic finite automaton monadic second quantum logic quantum language quantum computation Kleene theorem

A note on the crossed product r(A, α) associated with pSL_2(r)

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science.china Mathematics 2008年第11期51卷 2081-2088页

作者： WU WenMing 1 School of Mathematical and computer science. Chongqing normal university, Chongqing 400047, china 2 department of Mathematical science. Tsinghua university, Beijing 100084, china School of Mathematical and computer science Chongqing Normal University Chongqing China department of Mathematical science Tsinghua University Beijing China

Given the hyperbolic measure dxdy/y2 on the upper half plane H, the rational actions of pSL2(r) on H induces a continuous unitary representation α of this group on the Hilbert space L2(H, dxdy/y2). Supposing that A = {Mf : f ∈ L∞(H, dxdy/y2)}, we show that the crossed product r(A,α) is of type I. In fact, the crossed product r(A,α) is *-isomorphic to the von Neumann algebra B(L2(p,ν))■LK, where LK is the abelian group von Neumann algebra generated by the left regular representation of K.

关键词： crossed product rational actions pSL2(r) von Neumann algebras

A secure multi-party computation solution to intersection problems of sets and rectangles

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progress in Natural science.Materials International 2006年第5期16卷 538-545页

作者： LI Shundong, DAI Yiqi, WANG Daoshun and LUO ping (department of computer science.and Technology, Beijing normal university, Beijing 100875, china department of computer science.and Technology, Tsinghua university, Beijing 100084, china) department of computer science.and Technology Beijing Normal University Beijing 100875 China department of computer science.and Technology Tsinghua University Beijing 100084 China

Secure multi-party computation (SMC) is a research focus in international cryptographic community. At present, there is no SMC solution to the intersection problem of sets. In this paper, we first propose a SMC solution to this problem. Applying Cantor encoding method to computational geometry problems, and based on the solution to set-intersection problem, we further propose solutions to points inclusion problem and intersection problem of rectangles and further prove their privacy-preserving property with widely accepted simulation paradigm. Compared with the known solutions, these new solutions are of less computational complexity and less communication complexity, and have obvious superiority in computational and communication complexity.

关键词： Cantor encoding secure multi-party computation set-intersection rectangle-intersection computational complexity.

randomization of classical inference patterns and its application

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science.in china(Series F) 2007年第6期50卷 867-877页

作者： WANG GuoJun1,2 & HUI xiaoJing1,31 Institute of Mathematics, Shaanxi normal university, xi’an 710062, china 2 research Center for science. xi’an Jiaotong university, xi’an 710049, china 3 College of Mathematics and computer science. Yan’an university, 716000, china Institute of Mathematics Shaanxi Normal University Xi’an China research Center for science Xi’an Jiaotong University Xi’an China College of Mathematics and computer science Yan’an University China

By means of randomization, the concept of D-randomized truth degree of formulas in two-valued propositional logic is introduced, and it is proved that the set of values of D-randomized truth degree of formulas has no isolated point in [0,1]. The concepts of D-logic pseudo-metric and D-logic metric space are also introduced and it is proved that there is no isolated point in the space. The new built D-randomized concepts are extensions of the corresponding concepts in quantified logic. Moreover, it is proved that the basic logic connectives are continuous operators in D-logic metric space. Lastly, three different types of approximate reasoning patterns are proposed.

关键词： D-randomized mapping D-randomized truth degree D-similarity D-logic metric space approximate reasoning

The counting series for (k+1)-uniform linear acyclic hypergraphs

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Chinese science.Bulletin 2001年第3期46卷 197-200页

作者： SHAN Zhilong & LIU Bolian department of Mathematics, South china normal university, Guangzhou 510631, china department of computer science. Guandong polytechnical normal university, Guangzhou 510633, china department of Mathematics South China Normal University Guangzhou China department of computer science Guandong Polytechnical Normal University Guangzhou China

The explicit formula for (k+l)-uniform linear acyclic hypergraphs and the counting series for unlabeled (k +1)-uniform linear acyclic hypergraphs are obtained.

关键词： hypergraph linear hypergraph hypertree bipartite tree polya’s Enumeration Theorem.

Transition from Metastablity to Instability in Dynamics for the precipitation of δ'(Al_3Li)

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rare Metals 2001年第4期20卷 240-247页

作者： xiaoling Li, Zheng Chen, Bing Liu, Yongxin Wang department of Materials science.and Engineering, Northwestern polytechnical university. xi’an, 710072. china 西北工业大学陕西西安 710072

A computer simulation study on dynamics for the precipitation of δ'(Al_3Li) ordered particles from a disor- dered matrix (α) in binary Al-Li alloys is performed using the microscopic Langevin equation. A unique precipitation mechanism is found near the ordering spinodal line. Different from the classical nucleation mechanism in the me- tastable region and the congruent ordering followed by spinodal decomposition in the instable region, a nonstoichi- ometric single ordered phase with composition fluctuations is formed by non-classical nucleation, and this ordered phase decomposes spinodally. It can be concluded that the precipitation dynamics of δ' phase from metastability to instability is gradual, and no sharp transition occurs near the mean-field spinodal line as the mean-field theory pre- dicts.

关键词： δ'(Al_3Li) precipitation dynamics non-classical nucleation gradual transition

AppLICATION OF NONLINEAr pID CONTrOLLEr IN AErODYNAMICS LOADING SYSTEM

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Chinese Journal of Aeronautics 1997年第2期10卷 155-160页

作者： Hu Fei Cai xiaobin Li Yanjun(department of computer science. Northwesternm polytechnicaluniversity, xi’an, 710072. china) department of computer science NW Polytechnical University Xi'an 710072 China

The design idea of tracking-differentiator and the nonlinear pID controllerare introduced, the applicable algorithm and its real result for distributed aerodynamicsloading control system are discussed, and the construction of the test & contro1 system arealso presented. The application shows that the nonlinear pID algorithm has the advan-tages of high reliability, short run time and strong stability.

关键词： aerodynamic loads nonlinearity proportional-integral-differential (controller) controllers test & control systems

EXACT EXpLICIT SOLUTIONS OF THE NONLINEAr SCHrDINGEr EQUATION COUpLED TO THE BOUSSINESQ EQUATION

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Acta Mathematica Scientia 2003年第4期23卷 453-460页

作者：姚若侠李志斌 department of computer science Weinan Teachers' College Weinan 714000 China department of computer science East China Normal University Shanghai 200062 China

A system comprised of the nonlinear Schrodinger equation coupled to the Boussinesq equation (S-B equations) which dealing with the stationary propagation of coupled non-linear upper-hybrid and magnetosonic waves in magnetized plasma is proposed. To examine its solitary wave solutions, a reduced set of ordinary differential equations are considered by a simple traveling wave transformation. It is then shown that several new solutions (either functional or parametrical) can be obtained systematically, in addition to rederiving all known ones by means of our simple and direct algebra method with the help of the computer algebra system Maple.

关键词： Coupled Schrodinger-Boussinesq equations traveling wave transformation riccati equations solitary wave solution