自仿射曲线的维数(Ⅱ)

用自仿射分形理论研究自仿射贡线,得到自仿射曲线ｄｉｍＨＦ＝ｄｉｍＢＦ的结论。     

一种链分子构象完全计算方案

提出了利用实际分子的键长、键角及二面角计算高分子链构象完全算的方案 ,以自由内旋转的聚乙烯链和聚环氧乙烷链为例进行计算 ,得到了与Flory矩阵方法相同的结果 .本方案得到了每一个质点坐标 ,比Flory矩阵方法得到更多的信息 .与格点计算模型相比 ,本方案可应用到真实分子体系 .     

电流变液中悬浮粒子形状对其性质的影响

采用近邻相互作用近似方法 ,计算了悬浮于液相中旋转椭球颗粒在外场下形成的不同结构的电偶极矩相互作用能 .发现相互作用能随c/a(c、a分别为椭球长、短半轴 )变化而变化 .这一现象显示悬浮颗粒的形状对电流变液的相互作用能有很大影响 .     

Protein functional-group 3D motif and its applications

Representing and recognizing protein active sites sequence motif (1D motif) and structural motif (3D motif) is an important topic for predicting and designing protein function. Prevalent methods for extracting and searching 3D motif always consider residue as the minimal unit, which have limited sensitivity. Here we present a new spatial representation of protein active sites, called "functional-group 3D motif ", based on the fact that the functional groups inside a residue contribute mostly to its function. Relevant algorithm and computer program are developed, which could be widely used in the function prediction and the study of structural-function relationship of proteins. As a test, we defined a functional-group 3D motif of the catalytic triad and oxyanion hole with the structure of porcine trypsin (PDB code: 1mct) as the template. With our motif-searching program, we successfully found similar sub-structures in trypsins, subtilisins and a/b hydrolases, which show distinct folds but share similar catalytic mechanism. Moreover, this motif can be used to elucidate the structural basis of other proteins with variant catalytic triads by comparing it to those proteins. Finally, we scanned this motif against a non-redundant protein structure database to find its matches, and the results demonstrated the potential application of functional group 3D motif in function prediction. Above all, compared with the other 3D-motif representations on residues, the functional group 3D motif achieves better representation of protein active region, which is more sensitive for protein function prediction.     

Moran sets in complete metric space

The Hausdorff dimensions and packing dimensions of Moran sets in the (C ,s)- homogeneous space are presented, which generalizes the results of Hua and Rao.     

天津市发展现代远程教育的需求分析

以天津市人口发展趋势和天津市教育发展规划为基础 ,分析了天津市高等教育资源的现状 ,以及传统教育方式下的高等教育供求矛盾 ,并以供求缺口作为现代远程教育的需求 ,指出现代远程教育方式是实现天津市教育发展规划目标的有效手段 .     

菲涅尔双棱镜干涉实验中凸透镜的选择

针对双棱镜干涉实验中大像难以观察到的情况,通过理论推导得出凸透镜焦距的界定范围。便于教师和仪器生产商选择合适的凸透镜。确保了实验的成功,完善了教材中关于凸透镜焦距的定义域。     

基于改进角点特征的多传感器图像配准

对模糊和有噪声干扰图像设计的高对比度角点提取算法进行了改进,将角点检测范围限定在高对比度“边缘带”,减少了角点检测范围,在保持角点检测精度的同时,算法效率提高了大约1倍.在点特征匹配阶段,采用归一化互相关初步建立点特征的对应关系,利用马氏距离仿射不变性筛选出正确点对,从而得到图像之间的仿射变换关系,实现图像的自动配准.实验结果证明了此算法的有效性和高效性.     

激光测距仪在海崖剖面形态快速测量中的应用

提出一种利用激光测距仪快速测量海崖及海蚀槽剖面形态的方法.选取福建省平潭岛东北部的7条海崖作为测量研究区,定时段进行崖面剖面形态的测量.结果表明:研究区中的4个海蚀槽均发育在距崖底1.0m高度范围内,且海蚀槽上部崖面的倾角大于下部崖面的倾角;一个断面的剖面测量只需7~16min,且能够测量人不易达到的区域.     

环F_q+uF_q+u~2F_q+…+u~(k-1)F_q上线性码的覆盖半径

文章研究了有限链环R=Fq+uFq+u2Fq+…+uk-1Fq上长为n的线性码关于齐次距离的覆盖半径,其中uk=0,q为某一素数幂。构造了环R上的广义Gray映射,得到了R上线性码关于覆盖半径的相关性质,并研究了环R上线性码覆盖半径的上下界。