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Lower Bounds of Size Ramsey Number for Graphs with Small Independence Number

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Acta Mathematicae Applicatae Sinica 2021年第4期37卷 841-846页

作者： Chun-lin you Center for Discrete Mathematics Fuzhou UniversityFuzhou 350108 China

Let r≥3 be an integer such that r−2 is a prime power and let H be a connected graph on n vertices with average degree at least d andα(H)≤βn,where 0nd2(r−2)2−Cn−−√for all sufficiently large n,where C is a constant depending only on r,d andβ.In particular,for integers k≥1,and r≥3 such that r−2 is a prime power,we have that there exists a constant C depending only on r and k such that R^(Pkn;r)>kn(r−2)2−Cn−−√−(k2+k)2(r−2)2 for all sufficiently large n,where P k n is the kth power of Pn.

关键词： size ramsey number affine plane probabilistic method

Divisor Class Halving Algorithms for Genus Three Hyperelliptic Curves

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Chinese Journal of Electronics 2020年第1期29卷 97-105页

作者： you lin YANG Yilin GAO Shuhong School of Cyberspace Security Hangzhou Dianzi University School of Mathematical and Statistical Sciences Clemson University

In an(hyper)elliptic curve cryptosystem,the most important operation or the most time-consuming operation is the divisor scalar multiplication which consists of a sequence of doubling(of divisor) and addition(of two divisors). Point halving algorithms for elliptic curve cryptosystem and divisor halving algorithms for genus-2 hyperelliptic curve cryptosystem had been successively put forward to take the place of doubling algorithms for speeding up(hyper)elliptic curve cryptosystem. We present an outline for an algorithm for divisor halving on genus-3 hyperelliptic curves over the binary field and give some explicit formulae for a class of genus-3 *** algorithm improves previously known best doubling algorithms in most cases. A halve-and-add binary method for divisor scalar multiplications is presented.

关键词： Genus-3 hyperelliptic curve cryptosystem Divisor scalar multiplication Divisor doubling Divisor halving

Chip morphology and cutting temperature of ADC12 aluminum alloy during high-speed milling

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Rare Metals 2021年第7期40卷 1915-1923页

作者： Xin-Xin Meng you-Xi lin School of Mechanical Engineering and Automation Fuzhou UniversityFuzhou 350108China

The ADC12 aluminum alloy is prone to severe tool wear and high cutting heat during high-speed milling because of its high *** study analyzes the highspeed milling process from the perspective of different chip *** influence of cutting temperature on chip morphology was expounded.A two-dimensional orthogonal cutting model was established for finite element analysis(FEA)of high-speed milling of ADC12 aluminum alloy.A theoretical analysis model of cutting force and cutting temperature was proposed based on metal cutting *** variations in chip shape,cutting force,and cutting temperature with cutting speed increasing were analyzed via *** results show that,with the increase in cutting speed,the chip morphology changes from continuous to serrated,and then back to *** serrated chip is weakened and the cutting temperature is lowered when the speed is lower than 600 m·min^(-1)or higher than 1800 m·min^(-1).This study provides a reference for reducing cutting temperature,controlling chip morphology and improving cutting tool life.

关键词： ADC12 aluminum alloy High-speed milling Chip morphology Cutting temperature Finite element analysis

Spatial distribution of dissolved Pb,Hg,Cd,Cu and As in the Bohai Sea

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Journal of Environmental Sciences 2007年第9期19卷 1061-1066页

作者： WANG Chang-you WANG Xiu-lin College of Chemistry and Chemical Engineering Ocean University of China Qingdao 266003 China.

Characteristics of the spatial distribution of selected dissolved heavy metals were analyzed during large scale surveys from August t2 to 25, 2003 in the Bohai Sea. Dissolved Pb was the only element with average concentrations higher than the grade-one sea water quality standard of China. The spatial distribution of dissolved Pb in surface water was similar to those of Cd, Cu and As, where the isopleths generally indicated decreasing values from the bays to the central areas. Only for Hg did the high concentrations not only appear in Liaodong Bay, Bohai Bay and Laizhou Bay, but also in the Central Area, viz. not only in inshore but also in offshore areas. Vertical distributions of dissolved Pb, Cd, Cu and As were largely uniform, while that of dissolved Hg increased with depth. We infer that the input of pollutants from land was the main influencing factor for the detected distribution patterns of dissolved heavy metals, followed by the dynamics of sea water, release from bottom sediments and biochemical processes. Comparing with historical data, average concentrations of dissolved heavy metals appear to decline in recent years.

关键词： dissolved heavy metals spatial distribution pollution surveys Bohai Sea

Digital signature systems based on smart card and fingerprint feature

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Journal of Systems Engineering and Electronics 2007年第4期18卷 825-834页

作者： you lin Xu Maozhi Zheng Zhiming Coll. of Communication Engineering Hangzhou Dianzi Univ. Hangzhou 310018 P. R. China School of Mathematics Peking University Beijing 100871 P. R. China School of Science Beijing Univ. of Aeronautics and Astronautics Beijing 100083 P. R. China

Two signature systems based on smart cards and fingerprint features are proposed. In one signature system, the cryptographic key is stored in the smart card and is only accessible when the signer＇s extracted fingerprint features match his stored template. To resist being tampered on public channel, the user＇s message and the signed message are encrypted by the signer＇s public key and the user＇s public key, respectively. In the other signature system, the keys are generated by combining the signer＇s fingerprint features, check bits, and a rememberable key, and there are no matching process and keys stored on the smart card. Additionally, there is generally more than one public key in this system, that is, there exist some pseudo public keys except a real one.

关键词： digital signature fingerprint feature error-correcting code cryptographic key smart card

Two-Level linear Relaxation Method for Generalized linear Fractional Programming

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Journal of the Operations Research Society of China 2023年第3期11卷 569-594页

作者： Hong-Wei Jiao you-lin Shang Postdoctoral Research Base Henan Institute of Science and TechnologyXinxiang453003HenanChina Postdoctoral Research Station of Control Science and Engineering Henan University of Science and TechnologyLuoyang471023HenanChina

This paper presents an efficient algorithm for globally solving a generalized linear fractional programming *** establishing this algorithm,we firstly construct a two-level linear relaxation method,and by utilizing the method,we can convert the initial generalized linear fractional programming problem and its subproblems into a series of linear programming relaxation *** on the branch-and-bound framework and linear programming relaxation problems,a branch-and-bound algorithm is presented for globally solving the generalized linear fractional programming problem,and the computational complexity of the algorithm is ***,numerical experimental results demonstrate the feasibility and efficiency of the proposed algorithm.

关键词： Generalized linear fractional programming Global optimization Two-level linear relaxation method Branch-and-bound

Time-periodic Solution to a Nonlinear Parabolic Type Equation of Higher Order

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Acta Mathematicae Applicatae Sinica 2008年第1期24卷 129-140页

作者： Yan-ping Wang you-lin Zhang Department of Physics and Mathematics Zhengzhou Institute of Aeronautical Industry Management Zhengzhou 450015 China Institute of Applied Physics and Computational Mathematics P.O.Box 8009 Beijing 100088 China

In this paper, the existence and uniqueness of time-periodic generalized solutions and time-periodic classical solutions to a class of parabolic type equation of higher order are proved by Galerkin method.

关键词： Time-periodic solution nonlinear parabolic equation of higher order Ginzburg-Landau model equation

Circular Polarization in Pulsar Integrated Profiles: Updates

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Chinese Journal of Astronomy and Astrophysics 2006年第2期6卷 237-246页

作者： Xiao-Peng you Jin-lin Han National Astronomical Observatories Chinese Academy of Sciences Beijing 100012

We update the systematic studies of circular polarization in integrated pulse profiles by Han et al. Data of circular polarization profiles are compiled. Sense reversals can occur in core or cone components, or near the intersection between components. The correlation between the sense of circular polarization and the sense of position angle variation for conal-double pulsars is confirmed with a much large database. Circular polarization of some pulsars has clear changes with frequency. Circular polarization of millisecond pulsars is marginally different from that of normal pulsars.

关键词： polarization - pulsars: general

A Cancelable Fuzzy Vault Algorithm Based on Transformed Fingerprint Features

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Chinese Journal of Electronics 2017年第2期26卷 236-243页

作者： you lin YANG ling YU Wangke WU Zhendong College of Communication Engineering Hangzhou Dianzi University

Juels and Sudan proposed in 2002 an algorithm for computing a fuzzy vault that binds a user’s biometric template with his *** was suggested that this vault could be used to securely store one’s secret or a cryptographic key without losing his biometric ***,in this classical fuzzy vault,if an attacker captures multiple vaults generated from one biometric template,he is able to obtain some biometric template information by cross-matching,and then he can use it to illegally recover the secret *** overcome this disadvantage,in this paper,a cancelable fuzzy vault algorithm is proposed based on the user’s transformed fingerprint features which are used to generate a fuzzy *** novel fuzzy vault is secure and can overcome the cross-matching attack without intensive computational ***,the use of three check values makes our vault have a much higher probability to detect a false query fingerprint template than some other vault versions,and it will highly improve the probability whether the reconstructed polynomial is correct or not.

关键词： Cryptographic key Fuzzy vault Fin gerprint minutiae Transformed template Biometric cryptosystem