Blurred Defocused Image Restoration Based on FRFT

A technique for restoring the blurred image resulted from defocusing of the lens is proposed in this paper, which is based on fractional Fourier transform （FRFT）.The FRFT, as a powerful tool for the analysis of time-varying signals, is closely connected with the optical imaging system. FRFT also can describe optical imaging process just like Fresnel diffractions, so a defocused imaging model based on FRFT is established to explain the blur phenomena of defocusing image. The defocused imaging model is greatly different from the traditional point spread function （PSF） model, and enables to uncover the blur nature of non-focus image. Then, an image restoration method using the novel model is proposed to handle the blurred defocused image. The method adopted a new iterative phase retrieval approach which can approximately estimate phase signals from intensity signals of a single defocused image by means of FRFT. Restoring image may acquire sharp image by implementing inverse FRFT on complex image signal made from the estimated phase signals and intensity signals. Experimental results demonstrate that the method is effective in restoring blurred defocused image.     

Automatic Question Answering from Web Documents

A passage retrieval strategy for web-based question answering （QA） systems is proposed in our QA system. It firstly analyzes the question based on semantic patterns to obtain its syntactic and semantic information and then form initial queries. The queries are used to retrieve documents from the World Wide Web （WWW） using the Google search engine. The queries are then rewritten to form queries for passage retrieval in order to improve the precision. The relations between keywords in the question are employed in our query rewrite method. The experimental result on the question set of the TREC-2003 passage task shows that our system performs well for factoid questions.     

Harmonic Retrieval Embedded in Hybrid Colored Noise: a Novel Pisarenko Method Based on Cross-high-order Cumulant

Spectral estimation method is an effective method in the case of parameter estimation of sinusoid signal in noises.It always applies cross-spectral estimation theory and high-order self-spectral estimation methods up to now.Yule-Walker equation based on cross-fourth-order cumulant is developed and Pisarenko method is provided in this paper.Simulation results show that the method is effective to retrieve sinusoid signal frequencies from hybrid colored noises and has good performance.     

大规模互联网图像检索与模式挖掘

在互联网时代，爆炸式增长的数字图像不仅给图像检索带来巨大的技术挑战，同时也带来了很多机遇和研究问题的新思路．本文简单回顾了图像检索的三个阶段的研究历史．以及在此过程中数据量的增多给图像检索带来的影响，并对作为关键问题的特征提取方面的研究进行了深入的分析．本文尤其指出视觉模式挖掘是寻找中层特征表示并缩小语义鸿沟的重要研究方向，并根据视觉模式的表征粒度将其分为五种类别分别进行了介绍，从中可以看到大数据对于视觉模式挖掘的重要作用．     

喀斯特水示踪模型研究

本文提出了两个喀斯特管流场和一个渗流场示踪模型,并给出了它们的解析解和应用分析以及对它们的识别原理和方法。     

国际标准书号（ISBN）和国际标准刊号（ISSN）的含义及应用

阐述了国际标准书号（ISBN）、中国标准书号（CSBN）、国际标准刊号（ISSN）、中国标准刊号（CSSN）的组成，以及在文献信息检索中的应用。对在使用中存在的问题，提出了改进意见。     

Internet信息资源的利用与检索技巧

为了更有效地利用因特网信息资源，对因特网信息资源的分布，信息资源的特点，信息资源的类型，Web信息资源检索工具以及信息检索技巧作一个较为全面的介绍。     

TRADSTAT--世界贸易统计数据库

本文探讨了ＤａｔａＳｔａｒ系统世界贸易统计数据库（ＴＲＡＤＳＴＡＴ）的结构特点和检索方法，同时指出了该数据库的研究和利用在政府宏观经济决策、外贸进出口以及信息咨询工作等方面的重要意义     

面向CBR的末段高层反导 部署案例库构建与使用

为了使基于案例推理（CBR）技术在末段高层反导部署中的应用能更好地提高反导部署的效率，研究了末段高层反导部署案例库的构建与使用问题。 首先，研究了案例库的组织与构建问题，主要围绕案例的表达、案例库的组织结构和案例库的构建流程展开；其次，研究了案例库的应用，其核心内容是相似案例的检索匹配，并给出了实例分析；最后，研究了案例库的精简问题。     

论信息时代文献检索课教学内容的拓展

通过人们对信息的需求和传统检索课内容存在的缺陷这两方面的矛盾对比分析，阐述了文献检索课教学内容改革的必要性，并提出文献检索课的总体构想和具体扩展内容。