一种基于Edwards椭圆曲线的RFID标签芯片加密处理器设计

本文提出了一款基于二进制Edwards椭圆曲线的高能效椭圆曲线加密处理器.该处理器采用163位密钥,被设计用于无源射频识别(RFID)标签.为了保证椭圆曲线加密(ECC)处理器运算的安全性,处理器使用了二进制Edwards曲线作为加密曲线.ECC处理器中的逻辑运算模块所使用的有限域乘法器基于K-O分治算法进行了优化和设计.验证结果显示,该ECC处理器需要14 200个等效门面积,加密过程中完成一次标量乘法需要23 023个时钟周期和0.93μJ的能量.该ECC处理器可以满足RFID标签所需要的能耗、时间和面积要求.     

生态人类学的学科发展困境及思考

从文化生态学到生态人类学,这是文化人类学就民族文化对涉及生态问题进行探讨时又一分支学科在分野后成熟的重要标志。无论是文化生态学还是生态人类学,这一新兴学科的发展仍存在着许多难以逾越的局限性,为此,文章仅就该学科中亟待解决的一些难题提出思考。     

无线局域网在高校中应用分析

介绍了无线局域网基本工作原理和特点,通过跟有线网络的比较,体现了无线网路的优越性,分析了其在高校中实现的可能性．给高校网络将来的发展趋势提供了参考。     

Using local geopotential model to implement underwater passive navigation

A main aspect of underwater passive navigation is how to identify the vehicle location on an existing gravity map, and several matching algorithms as ICCP and SITAN are the most prevalent methods that many scholars are using. In this paper, a novel algorithm that is different from matching algorithms for passive navigation is developed. The algorithm implements underwater passive navigation by directly estimating the inertial errors through Kalman filter algorithm, and the key part of this implementation is a Fourier series based local geopotential model. Firstly, the principle of local geopotential model based on Fourier series is introduced in this paper, thus the discrete gravity anomalies data can be expressed analytically with respect to geographic coordinates to establish the observation equation required in the application of Kalman filter. Whereafter, the indicated gravity anomalies can be gotten by substituting the inertial positions to existing gravity anomalies map. Finally, the classical extended Kalman filter is introduced with the differences between measured gravity and indicated gravity used as observations to optimally estimate the errors of Inertial Navigation System (INS). This navigation algorithm is tested on simulated data with encouraging results. Although this algorithm is developed for underwater navigation using gravity data, it is equally applicable to other domains, for example vehicle navigation on magnetic or terrain data.     

江苏省经济增长与环境污染水平的关系分析

以环境库兹涅茨曲线(EKC)理论为基础,根据江苏省统计年鉴1990—2006年的经济与环境数据,构建了江苏省工业"三废"排放量的环境库兹涅茨曲线模型,分析了江苏省环境质量与经济之间的关系,并对"三废"排放量变化趋势进行理论估计.研究表明,江苏省环境库兹涅茨曲线并不完全符合标准的倒"U"形,而是呈现3种情况:工业废水曲线呈现非EKC关系;工业废气曲线为"U形+倒U形左侧",两个理论转折点的人均GDP分别为5 635元和16 587元;工业固废曲线为倒"U"形左侧,理论转折点的人均GDP为32 402元.     

增长曲线模型回归系数的岭型组合主成分估计

本文提出了增长曲线模型回归系数的一种新的改进估计．讨论了它的优良性,证明了参数区域的某个椭球内,这种新的估计优于最小二乘估计,且在均方误差的意义下是可容许估计。     

基于ECC的多重签名在电子政务中的应用

随着电子政务的快速发展,它的安全性和保密性的要求越来越高,在本文研究的电子政务提案表决方案中,我们运用椭圆曲线、中国门限剩余定理、多重签名等关键技术,进一步提高并确保电子政务的安全性和保密性。     

基于matlab的膝关节假体磨损松动中RSA运动学参数分析

通过建立RSA运动学参数与步态分析皮肤标记物运动学参数之间的对应关系,运用此对应关系,解决RSA无法获得患者步态分析运动条件下的假体及骨骼运动学参数,也同时解决了步态分析中皮肤标记物误差较大的问题。     

A tool path correction and compression algorithm for five-axis CNC machining

A novel approach is proposed for correcting command points and compressing discrete axis commands into a C2 continuous curve. The relationship between values of rotation angles and tool posture errors is firstly analyzed. A segmentation method based on values of rotation angles and lengths of adjacent points is then used to subdivide these command points into accuracy regions and smoothness regions. Since tool center points generated by CAD~CAM system are usually lying in the space that is apart from the desired curve within a tolerance distance, and the corresponding tool orientation vector may change a lot while the trajectory length of the tool center point is quite small, directly machining with such points will lead to problems of coarse working shape and long machining time. A correction method for command points is implemented so that good processing effectiveness can be achieved. Also, the quintic spline is used for compressing discrete command points into a C2 continuous smooth curve. The machining experiment is finally conducted to demonstrate the effectiveness of the proposed algorithm.