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   

Test Development with Performance Standards and Achievement Growth in Mind     

Steve Ferrara  Dubravka Svetina  Sylvia Skucha  Anne H. Davidson 《Educational Measurement》2011,30(4):3-15

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基于带内自回传小基站系统的干扰抑制方案     

张静雷  邱玲 《中国科学院大学学报》2016,33(4):548-553

基于带内自回传小基站系统，提出一种以用户为中心动态成簇的部分协作干扰抑制方案。根据带内自回传小基站复用接入与回传无线资源的特点，形成以最大化系统下行接入链路吞吐量为目标，联合回传链路资源分配与接入链路预编码设计的优化问题。由于所提问题难以获得最优解，基于凸松弛和分块坐标下降方法，提出一种次优的迭代求解算法。仿真结果表明所提算法能根据回传速率调整协作簇的大小，均衡小基站回传负载，提升系统接入链路的吞吐量。  相似文献   

Java中文编码问题的产生与处理     

刘继峰  王一五 《大连大学学报》2006,27(4):108-111

JSP和Servlet是基于Java语言的跨平台W eb开发工具.在进行网络编程设计中,人们常碰见中文字符编码处理等问题.本文通过介绍字符集编码相关理论,并分析JSP和Servlet运行各阶段字符的编码形式,提出解决中文字符编码转换问题的方法.  相似文献   

心电信号小波变换自适应编码压缩方法     

蒋学程 《闽江学院学报》2006,27(2):45-48

动态心电监护具有监测时间长、数据量大的特点,所以心电数据压缩十分必要．对于心电信号压缩的方法有很多,文章提出了心电信号小波变换自适应编码压缩方法,与其它压缩方法相比,此方法减少了信号重建时的失真,压缩比5到12．  相似文献   

用偏振缠绕的光子对进行量子通讯和密集编码     

张登玉 《零陵学院学报》1997,(Z1)

研究如何利用两粒子形成的EPR-Bell态传输光子的量子态,并提出依赖于两光子缠绕的密集编码实验设想。  相似文献   

Adaptive early termination of fast mode decision in MVC based on inter-view correlation     

����Ȩ  ������  ��߲� 《上海大学学报(英文版)》2011,15(4):321-324

Variable size motion estimation (ME) and disparity estimation (DE) are employed to select the best coding mode for each macroblock (MB) in the current joint multiview video model (JMVM).This technique achieves the highest possible coding efficiency,but it results in extremely large computation complexity which obstructs the multiview video coding (MVC) from practical application.This paper proposes an adaptive early termination of fast mode decision algorithm for MVC.It makes use of the coding information o...  相似文献   

一种快速、有效的量化与基于小波的图像压缩     

林花荣  蒋军 《黄山学院学报》2006,8(3):27-28

量化是利用小波变换的图像压缩编码技术的关键环节之一。矢量量化和标量量化各有长短,二者有机地结合起来,称为混合量化(HQ—Hybrid Quantization)。它既有矢量量化的高效率,又具有标量量化的简单性,不需要进行码书训练,不要做乘除法。  相似文献   

创新档号编码方式适应现代化干部档案管理模式     

柏娟 《青海师专学报》2003,23(6):128-130

随着档案管理现代化程度的不断提高，特别是数字档案的产生，使得档案在分类检索的方法上越来越合理，也更为实用．干部人事档案作为其中一个门类，它的检索手段也不断的得到改进和发展，针对时下对干部人事档案管理的新要求，本文对干部人事档案的编号规则进行了探讨，认为音序编码方式可以适应快速发展的信息管理．  相似文献   

Unique-order interpolative coding for fast querying and space-efficient indexing in information retrieval systems     

Cher-Sheng Cheng  Jean Jyh-Jiun Shann  Chung-Ping Chung 《Information processing & management》2006

This paper presents a size reduction method for the inverted file, the most suitable indexing structure for an information retrieval system (IRS). We notice that in an inverted file the document identifiers for a given word are usually clustered. While this clustering property can be used in reducing the size of the inverted file, good compression as well as fast decompression must both be available. In this paper, we present a method that can facilitate coding and decoding processes for interpolative coding using recursion elimination and loop unwinding. We call this method the unique-order interpolative coding. It can calculate the lower and upper bounds of every document identifier for a binary code without using a recursive process, hence the decompression time can be greatly reduced. Moreover, it also can exploit document identifier clustering to compress the inverted file efficiently. Compared with the other well-known compression methods, our method provides fast decoding speed and excellent compression. This method can also be used to support a self-indexing strategy. Therefore our research work in this paper provides a feasible way to build a fast and space-economical IRS.  相似文献