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Threshold proxy quantum signature scheme with threshold shared verification

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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 10004.,china 1. College of Computer Science and Technology Beijing University of Technology Beijing 100124 China 3. State Key Laboratory of Integrated Services Network Xidian University Xi’an 710071 China 4. State Key Laboratory of Information Security ({1. university of Chinese Academy of Sciences) Beijing 100049 China 2. State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing 100876 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

Threshold quantum secret sharing between multi-party and multi-party

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Science china(Physics,Mechanics & Astronomy) 2008年第9期51卷 1308-1315页

作者： YANG YuGuang1.2,3 & WEN QiaoYan4.1.College of Computer Science and Technology,{1. university of Technology,{1. 1.01.4.china 2 State Key Laboratory of Integrated Services Network,Xidian university,Xi’an 71.071.china 3 State Key Laboratory of Information Security (graduate university of Chinese Academy of Sciences),{1. 1.004.,china 4.State Key Laboratory of Networking and Switching Technology,{1. university of Posts and Tele-communications,{1. 1.0876,china College of Computer Science and Technology Beijing University of Technology Beijing 100124 China State Key Laboratory of Integrated Services Network Xidian University Xi’an 710071 China State Key Laboratory of Information Security (graduate {1. of Chinese Academy of Sciences) Beijing 100049 China State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing 100876 China

A threshold quantum secret sharing (TQSS) scheme between multi-party and multi-party was proposed using a sequence of single photons,which is useful and efficient when the parties of communication are not all present. We described the process of this TQSS scheme and discussed its security. It was shown that entan-glement is not necessary for quantum secret sharing. Moreover,the theoretic effi-ciency was improved to approach 1.0% as almost all the instances can be used for generating the private key,and each photon can carry one bit of information. This protocol is feasible with the present-day technique.

关键词： threshold quantum secret sharing quantum cryptography single photon multi-party and multi-party

A NOTE ON THE CONSISTENCY OF LS ESTIMATES IN LINEAR MODELS

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Chinese Annals of Mathematics,Series B 2001年第4期22卷 471-474页

作者： CHEN XIRU The graduate School at {1., university of Science and Technology of china,{4., china. The graduate School at {1. University of Science and Technology of China Beijing 100039 China

It is well known that when the random errors are iid. with finite variance, the week and the strong consiStency of LS estimate of multiple regression coefficients are equivalent. This note, by constructing a counter-example, shows that this equivalence no longer holds true in case that the random errors possess only the r-th moment with 1.5 T ＜ 2.

关键词： Linear regression model Consistency LS estimate

Biomass estimation and uncertainty analysis based on CBERS-02 CCD camera data and field measurement

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Science china(Technological Sciences) 2005年第S2期48卷 116-128页

作者： CHEN Liangfu1.2, GAO Yanhua1.3, CHENG Yu1.3, WEI Zheng1.3, XIAO Qing1.4. LIU Qinhuo1. YU Tao1. LIU Qijing5, GU Xingfa1.& TIAN Guoliang1.1. State Key Laboratory of Remote Sensing Science, Institute of Remote Sensing Applications, Chinese Academy of Sciences, {1. 1.01.1. china 2. Geography and Environment College, Jiangxi Normal university, Nanchang 330027, china 3. {4. university of Chinese Academy of Sciences, beijing 1.0039, china 4. {1. Research Institute of Uranium Geology, {1. 1.0875, china 5. Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, {1. 1.01.1. china 1. State Key Laboratory of Remote Sensing Science Institute of Remote Sensing Applications Chinese Academy of Sciences 100101 Beijing China 2. Geography and Environment College Jiangxi Normal University 330027 Nanchang China 3. graduate {1. of Chinese Academy of Sciences 100039 Beijing China 4. {1. Research Institute of Uranium Geology 100875 Beijing China 5. Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences 100101 Beijing China

The study site is located in Qianyanzhou experimental station and the surrounding area. Based on CBERS-02 satellite data and field measurement, we not only discussed the relationship between NDVI and biomass of two species of coniferous plantations, namely, Pinus massoniana Lamb and Pinus elliottii Engelm, but also introduced the biomass models based on NDVI. The comparison between measured biomass in Qianyanzhou and biomass derived from CBERS-02 CCD data showed that it is feasible to estimate biomass based on NDVI. But its limitations cannot be ignored. This kind of model depends on the dominant vegetation species. There are some effect factors in estimating biomass based on NDVI. This paper analyzes these factors based on fine-resolution CBERS-02 CCD data and some conclusions are drawn: In Qianyanzhou, the area with good vegetation coverage, the nonlinearity of NDVI has little influence on scaling-up of NDVI. As a result of surface heterogeneity, scaling-up can cause NDVI within each pixel to change. Because scaling-up can cause pixel attribute to change, the applicability of biomass model is one of the sources of error in estimating biomass.

关键词： NDVI biomass scaling effect scaling-up.

The regular representation and regular covariant representation of crossed products of Woronowicz C^(*)-algebras

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Science china Mathematics 2005年第9期48卷 1245-1259页

作者： ZHANG Xiaoxia~(1.2) & GUO Maozheng~(1.3) 1. School of Mathematical Sciences,Peking university,{1. 1.0871.china 2. Department of Mathematics,Yantai university,Yantai 264.05,china 3. LMAM,Peking university,{1. 1.0871.china 1. School of Mathematical Sciences Peking University 100871 Beijing China 2. Department of Mathematics Yantai University 264005 Yantai China 3. LMAM Peking University 100871 Beijing China

In this paper,it is shown that the regular representation and regular covariant representation of the crossed products A×α G correspond to the twisted multiplicative unitary operators,where A is a Woronowicz C~*-algebra acted upon by a discrete group ***,it is also shown that the regular covariant C~*-algebra is the Woronowicz C~*-algebra which corresponds to a multiplicative ***,an explicit description of the multiplicative unitary operator for C(SU_q(2) )×α (?) is given in terms of those of the Woronowicz C~*-algebra C(SU_q(2) ) and the discrete group G.

关键词： multiplicative unitary operator, Woronowicz C*-algebra, crossed product.

Point Groups and Single Forms of Quasicrystals with Eightfold and Twelvefold Symmetry

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Acta Geologica Sinica(English Edition) 1989年第1期63卷 39-43页

作者： Shi Nicheng and Liao Libing beijing {1. School, china university of Geosiences, beijing beijing {1. School China University of Geosiences Beijing

This paper mainly deals with the point groups and single forms of octagonal quasicrystals and the description of one-dimensional quasilattice. The authors present a new sequence for describing the arrangement of quasiperiods in one-dimensional quasilattice. The first ten numbers of quasiperiods of this sequence are 1. 1. 2, 5, 1., 29, 70, 1.9, 4.8 and 985. The arrangement of quasiperiods in the first five steps are a, b, ab. babab and babababbabab. Seven p(?)nt groups and nine single forms for the octagonal system have been deduced, They are as follows: Point groups: 8.8m, 82, 8/m, 8/mmm, 8 and 82m; single forms: octagonal prism, dioctagonal prism. octagonal pyramid. dioctagonal pyramid. octagonal dipyramid, dioctagonal dipyramid, octagonal scalenohedron, dioctagonal scalenohedron and octagonal trapezohedron. Besides seven point groups and nine single forms for the dodecahegonal system have also been deduced.

关键词： Point Groups and Single Forms of Quasicrystals with Eightfold and Twelvefold Symmetry

ORDER RESULTS FOR ALGEBRAICALLY STABLEMONO-IMPLICIT RUNGE-KUTTA METHODS

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Journal of Computational Mathematics 1999年第6期17卷 639-644页

作者： Ai-guo Xiao(1. Department of Mathematics, Xiangtan university, Xiangtan {1.1.05, china2. ICMSEC, Chinese Academy of Sciences, beijing 1.080, china) Xiangtan Univ Dept Math Poona 411005 Maharashtra India Chinese Acad Sci ICMSEC Beijing 100080 Peoples R China

It is well known that mono-implicit Runge-Kutta methods have been applied in the efficient numerical solution of initial or boundary value problems of ordinary differential equations. Burrage (1.94. has shown that the order of an s-stage monoimplicit Runge-Kutta method is at most s+1.and the stage order is at most 3. In this paper, it is shown that the order of an s-stage mono-implicit Runge-Kutta method being algebraically stable is at most min((s) over tilde, 4., and the stage order together with the optimal B-convergence order is at most min(s, 2), where [GRAPHICS]

关键词： ordinary differential equations mono-implicit Runge-Kutta methods order algebraical stability

Calculating soil moisture by remote sensing and analyzing hydrologic cycle process in the Yellow River basin

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Science china(Technological Sciences) 2004年第z1期47卷 1-13页

作者： YANG Shengtian1.& LIU Changming1. 2 1. School of Environmental Sciences, beijing Normal {1., beijing 1.0875, china 2. Institute of Geographic Science and Natural Resources Research, beijing 1.01.1. china beijing Normal Univ Sch Environm Sci Beijing 100875 Peoples R China Inst Geog Sci & Nat Resources Beijing 100101 Peoples R China

Based on the AVHRR pathfinder remote sensing data, soil moisture, precipitation and evaporation during the period of 1.82—1.98, soil moisture of all layers of soil-profile (0—1.m) in the Yellow River basin over the 1. years are calculated by the remote sensing model of calculating soil water. The Yellow River basin is divided into seven subcatchments as control sections at the location of six hydrologic stations (Lanzhou, Toudaoguai, Longmen, Sanmenxia, Huayuankou and Lijin). After calculating soil moisture and obtaining runoff data and precipitation data, the dynamical features of hydrological cycle in the Yellow River basin are analyzed for the period from 1.82 to 1.88 using water balance method. The conclusions are as follows: It is feasible to calculate the soil water on the macro-scale, in the soil profile with temporal continuity by means of remote sensing and survey in land. Some values of the key water cycle factors in the Yellow River are obtained, which include the annual precipitation of 4.00 km3, the evapotranspiration of 3000-3500 km3, and the soil moisture transformation of ?500- 500 km3. Consequently, we analyzed the process of the water cycle in the Yellow River over the 1. years, and the results show that the segment upstream of Lanzhou city is a relatively humid region, and the area of internal waters and the reaches of Shanshan is the most desiccated region. Therefore, the runoff in the depth process is intensive and the runoff-generating process is weak in more arid regions.

关键词： the Yellow River, soil moisture, remote sensing, hydrologic cycle.

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Science china Earth Sciences 2004年第10期47卷 886-895页

作者： TANG Liangjie1.2, JIA Chengzao3, PI Xuejun4. CHEN Suping1.2, WANG Zhiyu5, XIE Huiwen4.1. Key Laboratory for Hydrocarbon Accumulation of Education Ministry, beijing 1.224., china 2. Basin & Reservoir Research Center, university of Petroleum, beijing 1.224., china 3. Petrochina Company Limited, beijing 1.001., china 4. Tarim Oilfield Company, Petrochina Company Ltd., Kurle 84.000, china 5. Department of Geology, university of Petroleum, beijing 1.224., china 1. Key Laboratory for Hydrocarbon Accumulation of Education Ministry 102249 Beijing China 2. Basin & Reservoir Research Center University of Petroleum 102249 Beijing China 3. Petrochina Company Limited 100011 Beijing China 4. Tarim Oilfield Company PetroChina Company Ltd. 841000 Kurle China 5. Department of Geology University of Petroleum 102249 Beijing China

The salt beds of Lower Tertiary developed in the mid-segment of Kuqa foreland fold belt, northern Tarim basin. They considerably controlled structural deformation of the belt. Ac- cording to the field observation, seismic profile interpretation and drilling data, three different structural styles of supra-salt, intra-salt and sub-salt occurred in the Kuqa foreland fold belt. Su- pra-salt structural styles mainly include thrust faults and fault-related sags. Intra-slat structural styles essentially are salt-pillows, intra-salt faults and folds, and salt weld structures. Sub-salt structural styles mainly consist of imbricated thrust faults, duplex structures, pop-up and fault-related folds. It is indicated that great differences exist among supra-salt, intra-salt and sub-salt structures of Kuqa foreland fold belt. The salt-related structures were formed in the same structural stress field. The dynamic mechanism of the salt-related structures is mainly associated with gravitation, compression and plastic flow of salt beds.

关键词： salt-related structural style, supra-salt structure, intra-salt structure, sub-salt structure, Kuga foreland fold belt.