Latent class DEDICOM

A probabilistic DEDICOM model was proposed for mobility tables. The model attempts to explain observed transition probabilities by a latent mobility table and a set of transition probabilities from latent classes to observed classes. The model captures asymmetry in observed mobility tables by asymmetric latent mobility tables. It may be viewed as a special case of both the latent class model and DEDICOM with special constraints. A maximum penalized likelihood (MPL) method was developed for parameter estimation. The EM algorithm was adapted for the MPL estimation. Two examples were given to illustrate the proposed method. The work reported in this paper has been supported by grant A6394 to the first author from the Natural Sciences and Engineering Research Council of Canada and by a fellowship of the Royal Netherlands Academy of Arts and Sciences to the second author. We would like to thank anonymous reviewers for their insightful comments.     

Bergman空间上乘子的酉等价性

在这篇文章中，我们证明了：如果ψ1ψ2……ψ1∈，H∞（D），并且存在某个α∈D，使得（f-f（α））的内函数部分是一个有限的Blaschke乘积，Mψ1，Mψ2…Mψn与Mf作为Bergman空间上的乘子，则的充分必要条件是ψ1＝ψ2＝…＝ψn＝f＝常数，这里n≥2。     

光载波:光波相位调制的原理

本文提出了一种图像调制原理,即用一族密条纹调制另一幅条纹图,使其适于光学处理,称为光载波,并介绍了它在条纹图倍增中的应用。这是一个对光测力学中各种干涉条纹都适用的普遍方法。     

快速乘法器的设计与实现

基于有限域上椭圆曲线公开密匙协议的离散对数计算算法正日益成为热点,而有限域上的计算尤其是乘法计算极大地影响其加/解密速度.提出了一种复合域GF((2m1)m2)上的快速乘法器.该乘法器采用并行计算和串行计算相结合的方法,只增加少量硬件规模,将一次有限域乘法的计算速度由原来的m=m2m1个时钟周期降低到m2个时钟周期,从而大大地提高了乘法器的计算速度.     

Elliptic Curve Scalar Multiplication with x-Coordinate

This paper gives a comprehensive method to do Elliptic Curve Scalar Multiplication with only x-coordinate. Explicit point operation formulae for all types of defining equations of the curves are derived. For each type of curve, the performance is analyzed. The formulae are applied in Montgomery Ladder to get scalar multiplication algorithm operated with only x-coordinate. The new scalar multiplication has the same security level and computation amount with protected binary scalar multiplication （PBSM） against side channel attack, and has the advantages of higher security and little memory needed.     

CM elliptic curves and p-adic valuations of their L-series at s=1

For rational integers γ and λ, consider two families of (-1) and (-3) respectively. General formulae expressed by Weierstrass -functions are given for special values of Hecke L-series attached to such elliptic curves. The uniform lower bounds of 2-adic and 3-adic valuations of these values of Hecke L-series as well as global criteria for reaching these bounds are obtained. Moreover, when γ=2 and λ=2, 4, further results of 2-adic and 3-adic valuations are obtained for the corresponding curves in more general case of D1 and some restricted D2 respectively. These results are consistent with the predictions of the conjecture of Birch and Swinnerton-Dyer, and greatly develop and generalize some results in recent literature for more special cases.     

科技期刊表格的规范化

针对目前我国科技期刊中表格制作不规范的现象，提出期刊应统一使用三线表，结合实例，阐述了如何设计制作科学规范的三线表；重点解决了栏目线、项目栏的设置及辅助线的使用等问题。     

环境因素对光合细菌应用培养过程增殖的影响

对耐盐红螺菌科光合细菌的应用培养条件 (光源、温度、接种量、pH等 ) ,以及光合细菌细胞数量与OD6 6 0nm 的相关性进行了探讨 .试验结果表明 ,在日光为光源、高气温下 ,强日光对光合细菌的增殖有抑制作用 ;光合细菌形成优势生长的适宜接种量为 2 0 % - 30 % ,最适pH为 7- 8.光合细菌细胞与OD6 6 0nm 的回归关系为y =10 .799x+2 .7819.     

ORACLE游标中的多表UPDATE行锁讨论

介绍了Oracle中的封锁机制,分析了共享更新封锁的特点,并就游标中的多表更新行锁以及怎样避免死锁错误进行了讨论．     

高速铁路无砟轨道不平顺谱

研究提出了我国高速铁路无砟轨道不平顺谱的计算方法、轨道不平顺谱拟合公式及轨道不平顺谱图.为提高轨道不平顺谱的计算精度,研究提出了基于线性插值和小波分析方法的轨道不平顺检测数据异常值和趋势向剔除算法.同时通过不同窗函数长度、不同窗函数和不同谱估计方法的轨道不平顺谱计算对比分析,确定了轨道不平顺谱的计算方法.利用高速综合检测列车检测数据计算确定了高速铁路无砟轨道不平顺谱及其拟合公式,并引入倍频能量表反映高速铁路无砟轨道周期结构的影响.由轨道不平顺谱拟合公式与倍频能量表共同构成的高速铁路无砟轨道不平顺谱,为高速铁路设计、评估和养护维修等提供了依据.