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Decoy-state quantum key distribution for the heralded pair coherent state photon source with intensity fluctuations

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Science china(information Sciences) 2010年第12期53卷 2485-2494页

作者： ZHOU Chun, BAO WanSu & FU XiangQun institute of electronic {2., The PLA information engineering University, zhengzhou 450004, china institute of electronic {2. The PLA Information Engineering University Zhengzhou China

This paper characterizes two important properties of the photon number distribution of the heralded pair coherent state (HPCS) photon source. The formula of secret key generation rates for the decoy-state quantum key distribution with intensity fluctuation source is proved to hold true for the HPCS photon source. By numerical simulations, we show that the three-intensity decoy-state protocols for the HPCS photon source is efficiently getting close to the ideal decoy-state method. Moreover, we find that the HPCS source is more robust against intensity fluctuation than the weak coherent photon (WCP) source, but less stable than the heralded single photon source (HSPS).

关键词： quantum key distribution decoy states heralded pair coherent state intensity fluctuations

The GPS-gravimetry boundary value problem

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Science china Earth Sciences 2005年第3期48卷 398-405页

作者： YU Jinhai1,2.& ZHANG Chuanding2.1. institute of Geodesy and Geophysics of Chinese Academy of Sciences, Wuhan 430077, china 2. {2. information engineering University, {2. 450052. china institute of Geodesy and Geophysics of Chinese Academy of Sciences Wuhan China zhengzhou information {2. University Zhengzhou China

How to determine the earth’s external gravity field with the accuracy of O(T2. by making use of GPS data and gravity values measured on the earth’s surface is dealt with in this paper. There are two main steps: to extend these measured values on the earth’s surface onto the reference ellipsoid at first and then to seek for the integral solution of the external Neumann problem outside the ellipsoid. In addition, the corresponding judging criteria of accuracy to solve the GPS-gravity boundary value problem are established. The integral solution given in the paper not only contains all frequency-spectral information of the gravity field with the accuracy of O(T 2., but is also easily computed. In fact, the solution has great significance for both theory and prac- tice.

关键词： Neumann boundary value problem, integral solution, gravity disturbance.

A fingerprint feature extraction algorithm based on curvature of Bezier curve

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Progress in Natural Science:Materials International 2007年第11期17卷 1376-1381页

作者： Yuan Huaqiang1, Ye Yangdong2. Deng Jianguang2. Chai Xiaoguang1 and Li Yong1(1. School of Software, Dongguan University of technology, Dongguan 52.808, china 2. {2. engineering institute, zhengzhou University, zhengzhou 450001, china) School of Software Dongguan University of Technology Dongguan 523808 China information engineering {2. Zhengzhou University Zhengzhou 450001 China

Fingerprint feature extraction is a key step of fingerprint identification. A novel feature extraction algorithm is proposed in this paper, which describes fingerprint feature with the bending information of fingerprint ridges. Ridges in the specific region of fingerprint images are traced firstly in the algorithm, and then these ridges are fit with Bezier curve. Finally, the point that has the maximal curvature on Bezier curve is defined as a feature point. Experimental results demonstrate that this kind of feature points characterize the bending trend of fingerprint ridges effectively, and they are robust to noise, in addition, the extraction precision of this algorithm is also better than the conventional approaches.

关键词： fingerprint identification feature extraction Bezier curve curvature

Effects of Al on Microstructure and High-Temperature Wear Properties of Austenitic Heat-Resistant Steel

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Journal of Iron and Steel Research International 2012年第3期19卷 62-66页

作者： ZHANG Yan1, SUN Yu-fu2. ZHAO Jing-yu2. GUAN Shao-kang2.(1. School of Materials engineering, Nanjing institute of {2., Nanjing 2.1167, Jiangsu, china 2. School of Materials Science and engineering, zhengzhou University, zhengzhou 450002. Henan, china) School of Materials engineering Nanjing Institute of Technology Nanjing Jiangsu China School of Materials Science and engineering Zhengzhou University Zhengzhou Henan China

Microstructure and high-temperature dry sliding wear at 600 ~C in ambient air of austenitic heat-resistant steel ZG40Cr2.Ni2. with different contents （mass percent） of AI （0 to 7.10~） have been investigated. The results show that microstructures of 4.68% and 7.10% A1 addition content consist of the matrix and reinforcement of inter- metallic compound y＇ and carbide, while microstructures of ZG40Cr2.Ni2. without A1 and with A1 of 1.68% are ab- sent of y＇. Higher wear resistance than the original ZG40Cr2.Ni2. alloy is achieved in alloys with higher content of A1 under the same high-temperature wear test condition. The wear rates of Fe-2.Cr-2.Ni-7.10A1 and Fe-2.Cr-2.Ni- 4.68A1 are only 2..83% and 45.83% of that of Fe-2.Cr-2.Ni, respectively. Heat-resistant steels with higher con- tents of AI （4.72. and 7.10%） have higher hardness than those with lower contents of AI （1.68% and 0）. Wear mechanisms of ZG40Cr2.Ni2. are considered as severe plough plastic deformation and slight adhesive. However, wear mechanisms of Fe-2.Cr-2.Ni 4.68A1 are light micro-cutting and oxidation-wear, while that of Fe-2.Cr-2.Ni- 7. 10A1 are severe adhesive transfer and oxidation-wear_

关键词： austenitic heat resistant steel Al microstructure high-temperature sliding wear mechanism

A new approach based on PSO algorithm to find good computational encoding sequences

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Progress in Natural Science:Materials International 2007年第6期17卷 712-716页

作者： Cui Guangzhao1, Niu Yunyun1, Wang Yanfeng1, Zhang Xuncai2.and Pan Linqiang2.1. School of Electrical and electronic engineering, {2. University of Light Industry, {2. 450002. china 2. Research institute of Biomolecular Computer, Huazhong University of Science and technology, Wuhan 430074, china) School of Electrical and electronic engineering Zhengzhou University of Light Industry Zhengzhou 450002 China Research institute of Biomolecular Computer Huazhong University of Science and Technology Wuhan 430074 China

Computational encoding DNA sequence design is one of the most important steps in molecular computation. A lot of research work has been done to design reliable sequence library. A revised method based on the support system developed by Tanaka et al. is proposed here with different criteria to construct fitness function. Then we adapt particle swarm optimization (PSO) algorithm to our encoding problem. By using the new algorithm, a set of sequences with good quality is generated. The result also shows that our PSO-based approach could rapidly converge at the minimum level for an output of the simulation model. The celerity of the algorithm fits our requirements.

关键词： DNA computing computational encoding DNA sequences PSO algorithm fitness function

Response of flood discharging capacity to the deterioration of the lower Yellow River

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Science china(Technological Sciences) 2004年第Z1期47卷 152-160页

作者： LI Wenxue1, LI Yong2. YAO Wenyi2. SU Yunqi2.& ZHANG Xiaohua2.1. Yellow River engineering Consulting Co. Ltd., zhengzhou 450003, {2. 2. Yellow River institute of Hydraulic Research, zhengzhou 450003, {2. Yellow River engineering Consulting Co. Ltd. Zhengzhou China Yellow River institute of Hydraulic Research Zhengzhou China

Based on the clarifications of the deterioration characteristics of the lower Yellow River (LYR), the influence of river deterioration on flood discharging capacity is studied through theoretical derivation and analysis of field data. This study indicates that response of flood discharging capacity to river deterioration is nonlinear. Sediment depositions in the main channel cause the reductions of dominant discharge and thus the increase of initial flood stage. Reductions in the channel width result in the increases of the rising rate of flood stage and the decrease of flood discharging capacity.

关键词： flood discharging capacity, boundary condition, deterioration, sediment, the lower Yellow River.

Multiparty simultaneous quantum identity authentication with secret sharing

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Science china(Physics,Mechanics & Astronomy) 2008年第3期51卷 321-327页

作者： YANG YuGuang1,2.WEN QiaoYan3 & ZHANG Xing4,5 1 College of Computer Science and technology,Beijing University of technology,Beijing 10002.,{2. 2.State Key Laboratory of information Security (Graduate University of the Chinese Academy of Sciences),Beijing 100049,{2. 3 School of Science,Beijing University of Posts and Telecommunications,Beijing 100876,{2. 4 institute of electronic technology,information engineering University,zhengzhou 450004,{2. 5 Trusted Computing Laboratory,Beijing University of technology,Beijing 10002.,{2. College of Computer Science and technology Beijing University of Technology Beijing China State Key Laboratory of information Security (Graduate University of the Chinese Academy of Sciences) Beijing China School of Science Beijing University of Posts and Telecommunications Beijing China institute of electronic {2. Information Engineering University Zhengzhou China Trusted Computing Laboratory Beijing University of Technology Beijing China

Two multiparty simultaneous quantum identity authentication (MSQIA) protocols based on secret sharing are presented. All the users can be authenticated by a trusted third party (TTP) simultaneously. In the first protocol,the TTP shares a random key K with all the users using quantum secret sharing. The ith share acts as the authentication key of the ith user. When it is necessary to perform MSQIA,the TTP generates a random number R secretly and sends a sequence of single photons encoded with K and R to all the users. According to his share,each user performs the corresponding unitary operations on the single photon sequence sequentially. At last,the TTP can judge whether the impersonator exists. The sec-ond protocol is a modified version with a circular structure. The two protocols can be efficiently used for MSQIA in a network. They are feasible with current technol-ogy.

关键词： quantum identity authentication secret sharing quantum cryptography

Using New Fusion Operations to Improve Trust Expressiveness of Subjective Logic

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Wuhan University Journal of Natural Sciences 2011年第5期16卷 376-382页

作者： ZHOU Hongwei1,2.3,SHI Wenchang1,2.LIANG Zhaohui1,2.LIANG Bin1,2.1.Key Laboratory of Data engineering and Knowledge engineering,Ministry of Education,Beijing 100872.{2. 2.School of information,Renmin University of {2.,Beijing 100872.{2. 3.institute of electronic technology,information engineering University of PLA,zhengzhou 450004,Henan,{2. Key Laboratory of Data engineering and Knowledge engineering Ministry of Education Beijing China School of information Renmin University of China Beijing China institute of electronic {2. Information Engineering University of PLA Zhengzhou Henan China

Subjective logic provides a means to describe the trust relationship of the realworld. However, existing fusion operations it offers Weal fused opiniotts equally, which makes it impossible to deal with the weighted opinions effectively. A. Jcsang presents a solution, which combines the discounting operator and the fusion operator to produce the consensus to the problem. In this paper, we prove that this approach is unsuitable to deal with the weighted opinions because it increases the uncertainty of the consensus. To address the problem, we propose two novel fusion operators that are capable of fusing opinions according to the weight of opinion in a fair way, and one of the strengths of them is improving the trust expressiveness of subjective logic. Furthermore, we present the justification on their definitions with the mapping between the evidence space and the opinion space. Comparisons between existing operators and the ones we proposed show the effectiveness of our new fusion operations.

关键词： trust subjective logic opinion fusion weizht

Constructing quantum error correcting code via logic function

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Science china(information Sciences) 2010年第3期53卷 515-523页

作者： ZHONG ShuQin, MA Zhi & XU YaJie zhengzhou institute of {2. engineering, University of {2. engineering of china, zhengzhou 450002. china zhengzhou institute of {2. engineering University of Information Engineering of China Zhengzhou China

We present a systematic way to construct p-ary quantum error correcting codes using logic functions. As a consequence, for a given function with APC distance d′ 2. we can construct quantum codes with parameters ((n, K, d))p and gain a lower bound of K for all 2.d d′. The basic states of the constructed quantum codes can be stated and the sufficient conditions for saturating quantum Singleton bound are also discussed. We give quantum codes [[5, 1, 3]]p with p prime, [[6, 0, 4]], [[6, 2. 3]]p with p > 2.prime and [[2., 2. - 2. 2.] as examples constructed in this way.

关键词： quantum error-correcting code logic states APC distance