Inverted Index Compression Using Word-Aligned Binary Codes   总被引：3，自引：1，他引：3  

Vo Ngoc Anh  Alistair Moffat 《Information Retrieval》2005,8(1):151-166

We examine index representation techniques for document-based inverted files, and present a mechanism for compressing them using word-aligned binary codes. The new approach allows extremely fast decoding of inverted lists during query processing, while providing compression rates better than other high-throughput representations. Results are given for several large text collections in support of these claims, both for compression effectiveness and query efficiency.  相似文献   

Automatic Alphabet Recognition     

Maayan Geffet  Yair Wiseman  Dror Feitelson 《Information Retrieval》2005,8(1):25-40

The last step of the Information Retrieval process is to display the found documents to the user. However, some difficulties might occur at that point. English texts are usually written in the ASCII standard. Unlike the English language, many languages have different character sets, and do not have one standard. This plurality of standards causes problems, especially in a web environment, where one may download a document with an unknown standard. This paper suggests a purely automatic way of finding the standard which was used by the document writer based on the statistical letters distribution in the language. We developed a vector-space-based method that creates frequencies vectors for each letter of the language and then matches a new document's vectors to the pre-computed templates. The algorithm was applied on various types of corpora in Hebrew, Russian and English, and provides an efficient solution to the stated problem in most cases.  相似文献   

A new approach to explore the knowledge transition path in the evolution of science & technology: From the biology of restriction enzymes to their application in biotechnology     

Xiaojun Hu  Ronald Rousseau 《Journal of Informetrics》2018,12(3):842-857

In this contribution, we develop a new approach to explore the process of knowledge transition from discovery-oriented science to technological fields, via applications-oriented research, including a mediator set. This trajectory is referred to as the D-A-T trajectory. It is shown how it can be constructed and measures are proposed to characterize the relational strength among different environments (discovery oriented research, applications-oriented research and patents) and the speed of evolution. Our approach is illustrated by a case study of three fundamental restriction enzymes articles. Among other results we found that 387 patents cited 124 of the 988 articles (a share of 12.55%) in the mediator set. Defining the non-patent references (NPR) transition rate as the number of citing patents divided by the number of articles in the mediator set yields a value 0.392. Our results suggest that the D-A-T path acts as a backbone and reveals important “invisible contributions” of an original scientific work during its evolution from discovery oriented research to outside academia. Our contribution provides a useful tool for bridging the existing gap in detecting the transition of knowledge between science and technology.  相似文献   

中国剩余定理在曲面拼接中的应用     

王慧蕾 《通化师范学院学报》2005,26(4):15-16

用计算机代数方法,研究了两个二次曲面的光滑拼接,给出了应用中国剩余定理得到的在两个截面平行的条件下的三次拼接曲面,并且由此得到的拼接曲面还满足超限插值问题.  相似文献   

基于粗糙集的决策规则可靠性评估方法     

李一强  吕宁 《大观周刊》2011,(18):123-124,113

粗糙集理论是处理不精确、不准确数据的有效方法，但是通过粗糙集方法获得的决策规则对于不完整的信息承统和随机数据也是不确定的。本文描述了一个用于决策规则的可靠性评价方法。该方法独立于任何专用引申规则方法，并且参数能够被调整以适应不同的信息系统。  相似文献   

一类二元非乘积型Meyer-knig-Zeller概率算子的饱和定理     

刘生贵 《嘉应学院学报》2011,(11):10-14

借助二元抛物线引理,探讨一类二元非乘积型Meyer-knig and Zeller概率算子的饱和性,得到了一个点态饱和定理.  相似文献   

SAR原始数据压缩的自适应比特分配BAQ算法     

潘志刚  王小龙  李志勇 《中国科学院大学学报》2017,34(1):106-111

针对SAR原始数据压缩，在传统BAQ算法基础上，提出一种分块量化比特率可变的BAQ算法，在保持各分块平均比特率固定的前提下，针对不同的数据分块自适应选择量化比特率。与已有的改进型BAQ算法相比，比特率选择机制基于分块数据的信号功率大小，不需要成像区域的先验知识。新方法能够明显提高数据量化信噪比并降低SAR复图像相位误差，而运算复杂度增加很小，并可以实现分数比特率，适应于不同通信带宽的数据传输需要，增加了SAR原始数据实时传输的灵活性。  相似文献   

当代高低杠成套动作编排发展态势的研究     

竭晓安 《北京体育大学学报》2016,39(2):111-115

摘要：里约奥运周期高低杠成套动作的编排与伦敦奥运周期相比发生了较大变化，要保持我国的高低杠优势，编出符合国际潮流和有竞争力的高低杠成套动作，就必须了解当代国际高低杠成套动作编排的发展态势。本文通过技术统计、录像观察、比较分析等研究方法，分别选取伦敦和里约两个奥运周期中（2010年—2014年）的4届世锦赛和1届奥运会体操比赛的40套高低杠决赛动作为观察统计对象，对两个奥运周期成套动作的上法、下法、换杠动作、杠中动作、连接加分以及成套动作的数量进行了全面、深入的对比分析，得出当代高低杠成套动作编排的发展态势是：上法以A组低难度为主；换杠动作加难、加长，连续飞行换杠将成为潮流；杠中动作数量有所减少，成套动作的编排趋向于高难动作直接相连，成套动作数量将趋于减少；下法将朝着“旋空翻”的方向发展。  相似文献   

论我国陪审制的缺陷及重塑     

陈云英  万丽丽 《安顺学院学报》2005,(2)

我国陪审制在我国遭遇了尴尬局面,陪审制是我国司法改革的一个重要方面,为了充分实现社会主义的司法公正,该制度在我国就有存在的必要性。作者首先阐述了我国陪审制的历史沿革,并分析其立法和司法上存在的缺陷。在立法上,该制度没有宪法和相关的法律依据;在司法上,陪而不审的现象严重。在此基础上,作者对重塑我国陪审制的对策进行了思考,提出了重塑我国陪审制度的方案。  相似文献   

设置实验障碍强化素质教育     

宋明友 《巢湖学院学报》2007,9(3):149-151

为培养“宽专业、厚基础、能力强、素质高”的新型人才，传统的实验教学模式是不能很好地培养学生的创新精神和实践能力的。针对学生对一些纯粹的验证性实验不感兴趣，实验能力得不到提高的现象，笔者在多年的实验教学中，不断总结教学经验，在不影响实验效果的前提下，有意识设置实验障碍，以提高学生分析问题、解决问题的能力。  相似文献