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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 1. institute of electronic {2. The PLA Information Engineering University Zhengzhou 450004 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

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, {2. 2. Information engineering institute, zhengzhou university, zhengzhou 450001, {2.) School of Software， Dongguan university of technology， Dongguan 52.808， {2. Information engineering institute， {2. university， {2. 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) [a] School of Materials engineering Nanjing Institute of Technology Nanjing 211167 Jiangsu China [b] School of Materials Science and engineering Zhengzhou University Zhengzhou 450002 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) [a]School of Electrical and electronic engineering Zhengzhou University of Light Industry Zhengzhou China [b]Research institute of Biomolecular Computer Huazhong University of Scienc and Technology Wuhan 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

Main chemical ingredients of the celadon glaze from Qingliangsi kiln and Zhanggongxiang kiln

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Science china(Physics,Mechanics & Astronomy) 2006年第4期49卷 487-495页

作者： ZHAO Weijuan1, LU Xiaoke1, LI Guoxia1, GUO Min1, XIE Jianzhong1, GAO Zhengyao1, SUN Xinmin2. GUO Musen2. CHENG Huansheng3 & ZHANG Bin3 1. Faculty of Physical engineering, zhengzhou {2., zhengzhou 450052. china 2. Research institute of Cultural Relic and Archaeology, Henan Province, zhengzhou 450004, china 3. Research institute of Modern Physics, Fudan {2., Shanghai 2.0433, china 1. Faculty of Physical engineering Zhengzhou University Zhengzhou 450052 China 2. Research institute of Cultural Relic and Archaeology Henan Province Zhengzhou 450004 China 3. Research institute of Modern Physics Fudan University Shanghai 200433 China

The proton induced X-ray emission (PIXE) is used to determine the chemical ingredients of seven main elements in the samples of Ru Guan porcelain glazes and Ru Civil porcelain from Qingliangsi kiln in Baofeng County and the samples of celadon glaze from Zhanggongxiang kiln in Ruzhou City. The PIXE data are then analyzed by scatter analysis and fuzzy cluster method for determining their classification and provenance. The results show that there are obvious differences between the ingredients of glaze material of Ru Guan porcelain and Ru Civil porcelain from Qingliangsi kiln, of which the former ingredients are stable and its source is localized, and that the sources and ingredients of the glaze of Ru Guan porcelain and those of celadon glaze from Zhanggongxiang kiln are not wholly the same, of which the latter sources are much scattering.

关键词： Zhanggongxiang kiln, Qingliangsi kiln, the source of raw material, the proton induced X-ray emission.

Tribological Properties of SiC/Cu Composite at High Temperature

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Journal of Wuhan university of technology(Materials Science) 2009年第6期24卷 888-891页

作者：范冰冰张锐 zhengzhou institute of Aeronautical Industry Management School of Materials Science & engineering Zhengzhou University

SiC/Cu composites were prepared by hot pressing. The high temperature tribological properties of the composites were investigated. XRD, SEM techniques were carried out to characterize the samples. It is found that the friction coefficient of SiC/Cu composites increases with the increasing SiC content. The SiC reinforcement particles are worn down other than removed by pulling out during the wear test. Oxidation of Cu debris leads to the smooth contacting surface. Ring crack is formed under the cyclic wear test. The crack propagates through the damaged matrix and along the brittle interface between SiC particles and Cu matrix.

关键词： SiC/Cu composite tribological properties high temperature wear ring crack

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.,china 2.State Key Laboratory of Information Security (Graduate university of the Chinese Academy of Sciences),Beijing 100049,china 3 School of Science,Beijing university of Posts and Telecommunications,Beijing 100876,china 4 institute of electronic technology,Information engineering university,zhengzhou 450004,china 5 Trusted Computing Laboratory,Beijing university of technology,Beijing 10002.,china College of Computer Science technology Beijing University of Technology Beijing 100022 China State Key Laboratory of Information Security [Graduate university of the Chinese Academy of Sciences] Beijing 100049 China School of Science Beijing University of Posts Telecommunications Beijing 100876 China institute of electronic {2. Information Engineering University Zhengzhou 450004 China Trusted Computing Laboratory Beijing University of Technology Beijing 100022 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

Early Hydration of Composite Cement with Thermal Activated Coal Gangue

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Journal of Wuhan university of technology(Materials Science) 2010年第1期25卷 162-166页

作者：郭伟 Department of Material engineering Yancheng Institute of Technology institute of Material Science and engineering Nanjing University of Technology

Composite cement samples were prepared by mixing clinker, gypsum with burnt coal gangues which was calcined at various temperatures. The mechanical strength and Ca（OH）2.content in the cement paste were tested, and the paste composition and microstructure were analyzed by thermogravimetry-differential thermal analysis （TG-DSC）, X-ray diffraction（XRD）, scanning electronic microscopy （SEM） and pore structure analysis. Results demonstrate that the thermal activated coal gangue could accelerate the early hydration of cement clinker obviously, which promotes the gangue hydration itself. The early hydrated products of the cement are C-S-H gel, Ca（OH）2.and AFt. The cement with 30% （in mass） the gangue exhibits higher mechanical strength, and among all the cement samples the one with the gangue burnt at 700 ℃ displays the highest hydration rate, mechanical strength, the most gel pores and the lowest total porosity.

关键词： blended cement hydration microstructure hydration product

Effect of Post-spinning Modification on the PAN Precursors and Resulting Carbon Fibers

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Journal of Wuhan university of technology(Materials Science) 2006年第3期21卷 44-48页

作者：张旺玺 Department of Mechanics engineering Zhongyuan Institute of TechnologyZhengzhou 450070China

The impregnation of a special grade PAN precursor,fibers wus carried out in a 8 wt% KMnO4 aqueous solution to obtain modified PAN precursor fibers. The effects of modification on the chemical stncture and the mechanical properties of precursor fibers thermally stabilized and their resulting carbon fibers u＇ere characterized by the combiination use of densities, wide-angle X-ray diffraction （WAXD）, X-ray photoelectron speetroscopy （XPS）, elemental analysis （ EA ）, Fourier traasform infrared spectroscopy （FT-IR） and scanning electron microscope （SEM）, ***4 as a strong oxidizer can swell, oxidize and corrode the skin of a ***, and transform C≡N groups to C≡N ones, meamchile , it can decreuse the crystal .size increuse the orientation index and the costallinity index, furthermore it can increuse the densities of modified PAN precursors and resuhing thermally stabilized fibers. As a result, the carbon fibers developed from modified PAN fibers show an improvement in tensile strength of 31.2. % and an improvement in elongation of 77.78 % , but a decrease of 16. 52. in Young＇s modulus.

关键词： carbon fibers carbon precursor chemical treatment mechanical properties