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Construction of Boolean functions with maximum algebraic immunity and count of their annihilators at lowest degree

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science china(information sciences) 2010年第4期53卷 780-787页

作者： DU YuSong* & PEI DingYi school of mathematics and information sciences,{4., guangzhou 510006, china school of mathematics and information sciences Guangzhou University Guangzhou China

Boolean functions used in stream ciphers against algebraic attacks are required to have a necessary cryptographic property-high algebraic immunity (AI). In this paper, Boolean functions of even variables with the maximum AI are investigated. The number of independent annihilators at the lowest degree of Boolean functions of even variables with the maximum AI is determined. It is shown that when n is even, one can get an (n + 1)-variable Boolean function with the maximum AI from two n-variable Boolean functions with the maximum AI only if the Hamming weights of the two functions satisfy the given conditions. The nonlinearity of the Boolean functions obtained in this way is computed. Similarly, one can get an (n + 2)-variable Boolean function with the maximum AI from four n-variable Boolean functions with the maximum AI. The nonlinearity of a class of Boolean functions with the maximum AI is determined such that their Hamming weights are either the maximum or the minimum.

关键词： Boolean function algebraic attack algebraic immunity annihilator nonlinearity

胶-辽-吉带北段集安群中古元古代变质辉长岩侵入体成因研究及其地球动力学演化意义

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岩石学报 2024年第6期40卷 1922-1942页

作者：辛未丁正江许志河毛光周薄军委山东科技大学地球科学与工程学院青岛266590 山东省地质矿产勘查开发局济南250013 防灾科技学院地球科学学院三河065201

胶-辽-吉造山带北段辽河群和集安群中的古元古代镁铁质侵入体成因及其指示的地球动力学背景一直存在较大争议。原因之一在于研究资料多集中于辽河群中出露的镁铁质侵入体,而对集安群中的镁铁质侵入体报道较少,制约了对胶-辽-吉造山带地... 详细信息

胶-辽-吉造山带北段辽河群和集安群中的古元古代镁铁质侵入体成因及其指示的地球动力学背景一直存在较大争议。原因之一在于研究资料多集中于辽河群中出露的镁铁质侵入体,而对集安群中的镁铁质侵入体报道较少,制约了对胶-辽-吉造山带地球动力学演化的整体性认识。因此,本文对集安群中镁铁质侵入体进行详细的野外实地调查、地球化学、年代学和同位素研究,讨论这些岩石成因,揭示地幔源区性质并制约地球动力学背景。锆石LA-ICP-MS U-Pb定年结果显示这些变质辉长岩侵入体变质时代介于1866~1871Ma,为古元古代晚期的产物;一粒锆石核部207 Pb/206 Pb年龄为2139±14.a,可能代表了原岩的结晶时代。样品属于亚碱性系列,并具有向富铁成分演化的拉斑系列特征。岩石富集大离子亲石元素(如Ba、Rb、Sr和K),亏损高场强元素(如Nb、Ta和Ti);这些特征与典型岛弧玄武岩相似,指示了它们来自俯冲流体交代的地幔源区。结合样品2.07~2.4.Ga的一阶段Hf同位素模式年龄,认为交代作用发生在古元古代早期。本次研究的集安群中变质辉长岩侵入体与前人研究的辽河群中镁铁质岩石在结晶变质时代和地球化学特点方面具有很多相似性:(1)同属于亚碱性系列并具有向富铁成分演化的趋势;(2)相似的微量和稀土元素配分曲线;(3)具有高场强元素亏损和大离子亲石元素富集这一“俯冲流体交代信号”;(4.轻度富集的Sr-Nd-Hf同位素和古元古代早期的一阶段Hf同位素模式年龄;(5)一致的结晶年龄(2139~2099Ma)与变质时代(1879~1852Ma)。这些相似性指示了集安群和辽河群在古元古代早期可能经历了相同的岩浆-构造-变质事件。镁铁质岩石应来源于古元古代早期经历了俯冲流体交代的地幔源区。在构造环境判别图解上,集安群和辽河群中镁铁质岩石大部分样品都落入弧后盆地环境中。结合同期火成岩组合和演化特点,认为胶-辽-吉造山带东北段在古元古代早期处于弧后盆地背景中,古元古代晚期则处于造山后伸展的地球动力学背景下。

关键词：胶-辽-吉带变质辉长岩侵入体古元古代集安群岩石成因

Secure multi-party computation protocol for sequencing problem

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science china(information sciences) 2011年第8期54卷 1654-1662页

作者： TANG ChunMing 1,2,SHI GuiHua 1 & YAO ZhengAn 3 1 school of mathematics and information science,{4. university,{4. 510006, china 2State Key Laboratory of information Security, Institute of Software science,Chinese Academy of sciences,Beijing 100080,china 3 school of mathematics and Computational science,Sun Yat-Sen university,{4. 510275,china school of mathematics and information science Guangzhou University Guangzhou China State Key Laboratory of information Security Institute of Software Science Chinese Academy of Sciences Beijing China school of mathematics and Computational science Sun Yat-Sen University Guangzhou China

In the field of multi-party computation,an important problem is how to construct an efficient and secure multi-party computation protocol for certain specific *** the present study,we make use of a secret sharing scheme to construct an efficient and secure multi-party computation protocol for sequencing *** protocols are perfectly secure against both a passive adversary that can corrupt at most t (n-1)/2 participants, and an active adversary that can corrupt at most t < n/3 *** simplest sequencing problem is the Millionaires' problem.

关键词： secure multi-party computation sequencing problem secret sharing

Optical pulse compression using a nonlinear optical loop mirror constructed from dispersion decreasing fiber

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science china(Technological sciences) 2004年第1期47卷 33-50页

作者： CAO Wenhua & LIU Songhaoschool of information, Wuyi university, Jiangmen 529020, china school for information and Optoelectronic science and Engineering, South china Normal university, guangzhou 510631, china school of information Wuyi University Jiangmen China school for information and Optoelectronic science and Engineering South China Normal University Guangzhou China

A novel scheme to compress optical pulses is proposed and demonstrated numerically, which is based on a nonlinear optical loop mirror constructed from dispersion decreasing fiber (DDF). We show that, in contrast to the conventional soliton-effect pulse compression in which compressed pulses are always accompanied by pedestals and frequency chirps owning to nonlinear effects, the proposed scheme can completely suppress pulse pedestals and frequency chirps. Unlike the adiabatic compression technique in which DDF length must increase exponentially with input pulsewidth, the proposed scheme does not require adiabatic condition and therefore can be used to compress long pulses by using reasonable fiber lengths. For input pulses with peak powers higher than a threshold value, the compressed pulses can propagate like fundamental solitons. Furthermore, the scheme is fairly insensitive to small variations in the loop length and is more robust to higher-order nonlinear effects and initial frequency chirps than the adiabatic compression technique.

关键词： dispersion decreasing fiber (DDF), optical pulse compression, optical solitons.

On the diophantine equation X^2-(1+a^2)Y^4.=-2a

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science china mathematics 2010年第8期53卷 2143-2158页

作者： YUAN PingZhi 1 & ZHANG ZhongFeng 2 1 school of mathematics,South china Normal university,{4. 510631,china 2 school of mathematics & Computational science,Sun Yat-Sen university,{4. 510275,china school of mathematics South China Normal University Guangzhou China school of mathematics & Computational science Sun Yat-Sen University Guangzhou China

Let a≥1 be an *** this paper,we will prove the equation in the title has at most three positive integer solutions.

关键词： algebraic approximations continued fractions elliptic curves quartic equations

Atomic Force Microscopy-based Cell Nanostructure for Ligand-conjugated Quantum Dot Endocytosis

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Acta Biochimica et Biophysica Sinica 2006年第9期38卷 646-652页

作者： Yun-Long PAN~1* Ji-Ye CAI~2 Li QIN~3 Hao WANG~4. 1 The First Affiliated Hospital of Jinan university,guangzhou 510632,china 2 College of Life science and Technology,Jinan university,guangzhou 510632,china 3 Department of Histology and Embryology,Medical College of Jinan university,guangzhou 510632,china 4.information and Optoelectronic science and Engineering.South china Normal university,guangzhou 510631,china The First Affiliated Hospital of Jinan universityguangzhou 510632 China College of Life science and Technology Jinan UniversityGuangzhou 510632 China Department of Histology and Embryology Medical College of Jinan UniversityGuangzhou 510632 China school for information and Optoelectronic science and Engineering South China Normal UniversityGuangzhou 510631 China

While it has been well demonstrated that quantum dots (QDs) play an important role inbiological labeling both in vitro and in vivo,there is no report describing the cellular nanostructure basis ofreceptor-mediated ***,nanostructure evolution responses to the endocytosis of transferrin(Tf)-conjugated QDs were characterized by atomic force microscopy (AFM).AFM-based nanostructureanalysis demonstrated that the Tf-conjugated QDs were specifically and tightly bound to the cell receptorsand the nanostructure evolution is highly correlated with the cell membrane receptor-mediated ***,confocal microscopic and flow cytometry results have demonstrated the specificity anddynamic property of Tf-QD binding and *** found that the internalization of Tf-QD is linearlyrelated to ***,while the nanoparticles on the cell membrane increased,the endocytosis was stillvery active,suggesting that QD nanoparticles did not interfere sterically with the binding and function ***,ligand-conjugated QDs are potentially useful in biological labeling of cells at a nanometerscale.

关键词： quantum dot endocytosis nanostructure atomic force microscopy

A note for preconditioning nonsymmetric matrices

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Applied mathematics(A Journal of Chinese Universities) 2010年第1期25卷 93-100页

作者： CHEN Xiao-shan LI Wen school of mathematics, South china Normal university, {4. 510631, china school of mathematics South China Normal University Guangzhou China

In this paper, we consider preconditioners for generalized saddle point systems with a nonsymmetric coefficient matrix. A constraint preconditioner for this systems is constructed, and some spectral properties of the ... 详细信息

关键词： Preconditioner saddle point matrix minimal polynomial Schilder's factorization.

Transport network and flow mechanism of shallow ore-bearing magma in Tongling ore cluster area

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science china Earth sciences 2006年第4期49卷 397-407页

作者： DENG Jun1,2, WANG Qingfei1,2 , HUANG Dinghua3 , WAN Li4. YANG Liqiang1,2 & GAO Bangfei1,2 1. State Key Laboratory of Geological Processes and Mineral Resources, china university of Geosciences, Beijing 100083, china 2. Key Laboratory of Lithosphere Tectonics and Lithoprobing Technology of Ministry of Education, china university of Geo- sciences, Beijing 100083, china 3. Faculty of Earth sciences, china university of Geosciences, Wuhan 4.0074. china 4. school of mathematics and information science,{14., guangzhou 5104.5, china State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing China Key Laboratory of Lithosphere Tectonics and Lithoprobing Technology of Ministry of Education China University of Geosciences Beijing China Faculty of Earth sciences China University of Geosciences Wuhan China school of mathematics and information science Guangzhou University Guangzhou China

Abundant studies revealed that shallow intrusions of the Yanshanian epoch resulted in the mass mineralization of the Tongling region. Various evidences showed there existed a concealed magma chamber at ?10 km depth in the middle part of this region during Yanshanian epoch, from which the ore-forming magma was generated and then transported to the superficial layer. Yet the transport network and flow mechanism of the shallow ore-bearing magma, the key problem associ- ated with ore-forming process, was relatively little focused on. Integrate analysis of structural me- chanics, statistical fractal and geological facts suggested that NE trending high-angle fold-related thrust faults and the tessellated basement ones served as the main pathways for the shallow magma’s transporting, moreover, the saddle void spaces among adjacent strata in the folds upon this fault system provided the place for magma’s emplacement. So the folds in the upper part and faults in the lower part of the upper crust constituted the fluid’s transport and emplacement network. During the deformation of geologic body with multi-layer structure, the layers in the upper part tended to fold when received the jacking stress from the lower part, while the lower one inclined to fault undergoing loads of the upper part. And the producing probability of this structure assemblage was highly in- creased in the condition, such as in the Tongling area, that the mechanic rigidity of the lower layers was stronger than that of the upper ones. For the pre-existence of fluid-conducting network, the top magma with high volatile in the magma chamber transported rapidly to the superficial layer in dyking pattern, located in the void spaces of folds, filled and reconstructed them. The sudden drop of pres- sure caused the fluid unmixing from the magma and mass ore-forming elements concentration. Pulse activity of the dyking may be the principal reason why magmatic bodies in the Tongling area were spatially-temporally con

关键词： Tongling, structural network, magma intrusion, fractal, dyke.

A COMPARISON OF FORECASTING MODELS OF THE VOLATILITY IN SHENZHEN STOCK MARKET

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Acta Mathematica Scientia 2007年第1期27卷 125-136页

作者：庞素琳邓飞其王燕鸣 Department of mathematics Jinan university school of Automatic science & Engineering South china university of Technology school of mathematics & Lingnan College Zhongshan university

Based on the weekly closing price of Shenzhen Integrated Index, this article studies the volatility of Shenzhen Stock Market using three different models： Logistic, AR（1） and AR（2）. The time-variable parameters of Logistic regression model is estimated by using both the index smoothing method and the time-variable parameter estimation method. And both the AR（1） model and the AR（2） model of zero-mean series of the weekly dosing price and its zero-mean series of volatility rate are established based on the analysis results of zero-mean series of the weekly closing price, Six common statistical methods for error prediction are used to test the predicting results. These methods are： mean error （ME）, mean absolute error （MAE）, root mean squared error （RMSE）, mean absolute percentage error （MAPE）, Akaike＇s information criterion （AIC）, and Bayesian information criterion （BIC）. The investigation shows that AR（1） model exhibits the best predicting result, whereas AR（2） model exhibits predicting results that is intermediate between AR（1） model and the Logistic regression model.

关键词： Logistic regression model AR(1) model AR(2) model volatility