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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. zhengzhou information engineering university, zhengzhou 450052, China Institute of Geodesy and Geophysics of Chinese Academy of Sciences Wuhan China zhengzhou information engineering 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 LARGE CLASS OF BINARY ZCZ SEQUENCE FAMILIES CONSTRUCTED BY PERIOD DOUBLING

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Journal of Electronics(China) 2007年第3期24卷 301-304页

作者： Wang Jinsong Qi Wenfeng Dept of Applied Mathematics Zhengzhou Information Engineering University Zhengzhou 450002 China

In an Approximately Synchronized Code Division Multiple Access (AS-CDMA) commu-nication system,a family with large number of Zero Correlation Zone (ZCZ) sequences is desired,which can satisfy the rapid increase of users. This paper presents a method to generate a (2L ,2M ,Zc' z )-ZCZsequence family from an original (L ,M ,Z cz)-ZCZsequence family,where Z c' z =Zcz if Z czis even and Z c' z = Zcz 1if Z czis odd. This method can also recursively act on a ZCZ sequence family to construct a series of ZCZ sequence families with large sequence number and zero correlation zone length identical to or one less than that of original ZCZ sequences.

关键词： Approximately Synchronized Code Division Multiple Access (AS-CDMA) communication system Zero Correlation Zone (ZCZ) sequence families ZCZ length

Research of Attack Model Based on Finite Automaton

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Research of Attack Model Based on Finite Automaton

2012 National Conference on information Technology and Computer Science

作者： ZHANG Zhi-wei zhengzhou information engineering university zhengzhou,China YUE Yun-Tian zhengzhou information engineering university zhengzhou,China

According to the unknown of attack behavior in cyberspace,this paper presents an attack modeling method based on system states *** the model,the basic principle of the finite automaton is researched and attack entities of cyberspace are classified by attack process,it combines finite automaton with the changes of system state caused by attack entity,building the attack model of finite automaton,making an analysis of the model algorithm,and making a quantitative evaluation on attack cost,the success rate,exposure rate and evaluating severity of attack on ***,through the analysis of typical attack behavior by using network attack modeling,it shows that the model proposed is feasible and effective.

关键词： finite automaton attack model system states aggregation attack detection security early warning

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基于谱直方图和SOFM网络的纹理分类

计算机工程与应用 2004年第2期40卷 90-92,214页

作者：许漫坤平西建郑州信息工程大学信息工程学院郑州450002

提出了一种基于纹理谱直方图和自组织特征映射网络的纹理分类方法。引入像素的八近邻离散付氏变换犤5犦,随机选取局部纹理区域,计算所选纹理区域的纹理谱并量化得到谱直方图,将其作为自组织特征映射(SOFM)网络的特征模式输入并训练网络... 详细信息

提出了一种基于纹理谱直方图和自组织特征映射网络的纹理分类方法。引入像素的八近邻离散付氏变换犤5犦,随机选取局部纹理区域,计算所选纹理区域的纹理谱并量化得到谱直方图,将其作为自组织特征映射(SOFM)网络的特征模式输入并训练网络。训练结束后的拓扑输出层对应于纹理的不同类别。算法简单有效,对6类Brodatz纹理进行测试,得到了良好的分类效果。

关键词：纹理谱直方图 SOFM网络纹理分类

Generalized Bent Functions and Perfect Nonlinear Functions over Finite Fields

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Generalized Bent Functions and Perfect Nonlinear Functions o...

2011 IEEE International Conference on information Theory and information Security(ICITIS 2011)

作者： Jihong Teng Xiaoying Huang Zhibo Lu Department of mathematics and physics zhengzhou information engineering university zhengzhou China

In this paper,we firstly introduce some equivalent definitions of generalized Bent functions and perfect nonlinear functions over finite field,which indicate that generalized Bent functions and perfect nonlinear functions are quite *** the relationships of generalized Bent functions over finite field and generalized Bent functions over its prime field are suggested,as well as that of perfect nonlinear functions over finite field and vector generalized Bent functions over its prime field,which enable us to investigate the existence and constructions of perfect nonlinear functions over finite field through the vector Bent functions over the prime field.

关键词： Finite Field perfect nonlinear function Bent funcion generalized Bent function vector Bent function Chrestenson cycle spectra autocorrelation function

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拟Bent函数的性质和构造

数学学报（中文版） 2004年第6期47卷 1175-1184页

作者：张习勇韩文报郑州信息工程大学信息工程学院郑州450002

本文将基本2-群中拟Bent函数的概念推广到一般的有限Abel群中,统一了目前几乎所有的Bent函数概念,完全刻画了一类拟Bent函数和Bent函数的本质联系,给出了几种拟Bent函数的构造方法,拟Bent函数和相对差集的一种关系以及一种用拟Bent函数... 详细信息

本文将基本2-群中拟Bent函数的概念推广到一般的有限Abel群中,统一了目前几乎所有的Bent函数概念,完全刻画了一类拟Bent函数和Bent函数的本质联系,给出了几种拟Bent函数的构造方法,拟Bent函数和相对差集的一种关系以及一种用拟Bent函数构造Bent函数的方法.最后,利用Galois环和组合集,找到一类拟Bent函数.

关键词： Bent函数拟Bent函数 Galois环

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GPRS的网络结构和协议分析

通信技术 2002年第3X期35卷 59-61页

作者：乌欣胡捍英郑州信息工程大学郑州450002

首先介绍了GPRS网络的逻辑结构,从业务传输的角度讨论了GPRS网络中用到的各种传输协议,并且分析了在GPRS网络中各个通信实体之间接口信令协议。

关键词：通用分组无线业务 GSM 网络结构传输协议接口信令协议

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把握数学建模过程中的数学直观

数学的实践与认识 2001年第6期31卷 759-760页

作者：顾勇为归庆明朱建青郭建锋陈楚湘郑州信息工程大学测绘学院郑州450052

本文论述了数学直观及其在数学建模过程中的重要意义 ,分析了以往数学建模竞赛的几个实例 ,说明了数学直观在数学建模过程中是如何创造并发挥作用的 .

关键词：数学直观数学建模数学建模竞赛

Local and Global Character Sums

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Acta Mathematica Sinica,English Series 2000年第3期16卷 535-540页

作者： Chunlei Liu zhengzhou university of information engineering,zhengzhou 450002,P.R.China zhengzhou university of information engineering Zhengzhou 450002 P. R. China

Hua’s estimate is established for character sums in a number field.A relationship between liftings of a character sum in a local field is also studied.

关键词： Character sum Exponential sum