关于第二类Stirling数的一种新算法

本文给出第二类Ｓｔｉｒｌｉｎｇ数的一种新算法，并推出几个有用的推论。     

The refinement algorithm consideration in text clustering scheme based on multilevel graph

To construct a high efficient text clustering algorithm, the multilevel graph model and the refinement algorithm used in the uncoarsening phase is discussed, The model is applied to text clustering. The performance of clustering algorithm has to be improved with the refinement algorithm application, The experiment result demonstrated that the muhilevel graph text clustering algorithm is available,     

Study on properties of residue-residue contacts in protein

Residue-residue contacts are very important in forming protein structure. In this work, we calculated the average probability of residue-residue contacts in 470 globular proteins and analyzed the distribution of contacts in the different interval of residues using Contacts of Structural Units (CSU) and Structural Classification (SCOP) software. It was found that the relationship between the average probability PL and the residue distance L for four structural classes of proteins could be expressed as lgPL=a+b x L, where a and b are coefficients. We also discussed the connection between two aspects of proteins which have equal array residue number and found that the distribution probability was stable (or un-stable) if the proteins had the same (or different) compact (for example synthase) in the same structural class.     

A minimal axiom group for rough set based on quasi-ordering

Rough set axiomatization is one aspect of rough set study to characterize rough set theory using dependable and minimal axiom groups. Thus, rough set theory can be studied by logic and axiom system methods. The classic rough set theory is based on equivalent relation, but rough set theory based on reflexive and transitive relation (called quasi-ordering) has wide applications in the real world. To characterize topological rough set theory, an axiom group named RT, consisting of 4 axioms, is proposed. It is proved that the axiom group reliability in characterizing rough set theory based on similar relation is reasonable. Simultaneously, the minimization of the axiom group, which requires that each axiom is an equation and each is independent, is proved. The axiom group is helpful for researching rough set theory by logic and axiom system methods.     

厄米-高斯光束倾斜入射类透镜介质的近轴传输

将描述光在类透镜介质中传播的Helmholtz方程化为具有线性谐振子势的Schr dinger方程形式,借助于量子力学中的"含时"么正变换技术,解析求解光束倾斜入射到类透镜介质中传输时的场分布,得到场传输的传播核因子,研究任意倾斜入射光束位形的传输问题,并对厄米 高斯光束的传输进行计算.研究结果表明:厄米 高斯光束倾斜入射进类透镜介质束宽度的演变与光束正入射的情况一样,随传输距离作周期性变化,但因光束倾斜入射,厄米 高斯光束的传输出现了新效应,即光强分布中心不再沿直线,传播方向也不断变化,出现与横坐标相关的附加局域相因子.     

在导电界面反射电磁波的横向偏移研究进展

综述了在导电界面反射电磁波的横向偏移研究现状. 对在导电界面反射电磁波的横向偏移时间和横向偏移规律进行了分析, 并介绍了横向偏移随入射角变化曲线的分布特点. 对电磁波测井还介绍了电磁波横向偏移效应的校正方法及电磁波横向偏移所产生误差的量级分析, 电磁波波长越长, 对测量结果的影响就越大. 针对考虑非均匀电磁波横向偏移效应的测量问题, 指出了在实际应用中尚需解决的实际问题, 并展望今后的研究发展趋势和应用前景.     

VB.Net 2003中串行端口通信的实现

针对MSComm控件的不足,探讨在VB.Net2003中如何利用API函数来定义串行端口类,并通过一个应用实例介绍如何利用该类的声明来实现PC与可编程控制器之间的串行通信.这对开发高质量的串行通信有一定的应用和借鉴价值.     

利用TIRFM技术检测PC12细胞中类突触小囊泡的锚定和融合特性

受到广泛关注的神经递质的释放是通过突触囊泡与突触前膜的融合完成的．通过对单个囊泡动力学的分析发现，在突触囊泡分泌过程中除了“完全融合”（fullfusion）模式外，还存在着“部分融合即离开”（kissandrun）和“部分融合且停留”（kissandstay）两种融合模式．在神经元受到强烈刺激时，这两种分泌模式尤为重要．同时突触囊泡融合前的转运、锚定、激活过程在神经递质的释放和调节过程中起着很关键的作用．在高l（＋刺激下的PCI2细胞中，我们运用全内反射荧光显微镜（total internal reflection fluorescence microscopy，TmFM）技术，通过VAMP2．pHluorin和VAChT-TDimer2双色荧光成像的方法跟踪类突触小囊泡（synaptic vesicle-1ike microvesicles，SLMVs）的锚定和融合过程．结果表明，在高K^＋刺激的PC12细胞中，部分融合即离开这种分泌模式占主导地位，同时发现在高K^＋刺激下SLMVs在细胞膜上的停留时间增加了，说明被激活囊泡的囊泡数量增加．     

基于谱聚类的图像多尺度随机树分割

针对谱聚类（spectral clustering）应用于图像分割时权矩阵的谱难以计算的实际问题，定义了像素点与类之间的距离，给出一个采样数定理，设计了一个图像的分层分割（hierarchical divisive）算法．在利用该算法进行图像分割时，由于既要对待分类的点进行随机抽样，又要通过调节尺度因子来合并较小的类或拆分较大的类，因此图像的分割既具有随机性又具有多尺度特性，称之为基于谱聚类的图像多尺度随机树分割（multiscale stochastic hierarchical image segmentation byspectral clustering，简写为MSHISSC）．实验结果表明了算法的有效性．     

架设基于.NET的SMTP服务

在.NET Framework2.0版的System.Net.Mail命名空间中,新增了用于将电子邮件发送到简单邮件传输协议（SMTP）服务器的MailMessage类.本文应用MailMessage类及其From、To、Body、CC等关联属性以及Windows提供的IIS（Internet信息服务）,开发了一个基本的基于.NET的电子邮件发送服务以及一个电子邮件客户端软件MyMail.