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1.
Fingerprint identification has been a great challenge due to its complex search of database. This paper proposes an efficient fingerprint search algorithm based on database clustering, which narrows down the search space of fine matching. Fingerprint is non-uniformly partitioned by a circular tessellation to compute a multi-scale orientation field as the main search feature. The average ridge distance is employed as an auxiliary feature. A modified K-means clustering technique is proposed to partition the orientation feature space into clusters. Based on the database clustering, a hierarchical query processing is proposed to facilitate an efficient fingerprint search, which not only greatly speeds up the search process but also improves the retrieval accuracy. The experimental results show the effectiveness and superiority of the proposed fingerprint search algorithm.  相似文献   

2.
This paper proposes a new method to generate smooth transition frames for serializing Chinese sign-language video clips. Each transition frame is composed of images of arms, hands, head and torso. Of them, the hand images are computed based on 3D hand models, and images of other parts are selected from a database. Experimental results show the method provided by this paper can improve the joined video??s visual presentation.  相似文献   

3.
针对传统手写信息采集系统存在的信息获取不全面的弊端,设计了一种基于多维力传感器的手写信息采集系统,给出了系统的总体框架.系统以多维力传感器为核心,不仅实现了对手写过程静态轨迹信息的获取,同时实现了对手写多维力信息的获取.整个系统由用户接口模块、数据采集模块和数据处理模块组成,分析了各模块的设计思想和工作原理,并基于WinCE系统开发了一种手写信息采集系统.实验证明:该系统工作稳定,性能优良,实现了对手写过程中力和位置信息的全面获取.  相似文献   

4.
Retrieval speed and precision ultimately determine the success of any database system. This article outlines the challenges posed by distributed and heterogeneous database systems, including those that store unstructured data, and surveys recent work. Much work remains to help users retrieve information with ease and efficiency from a heterogeneous environment in which relational, object-oriented, textual, and pictorial databases coexist. The article outlines the progress that has been made in query processing in distributed relational database systems and heterogeneous and multidatabase systems  相似文献   

5.
基于颜色特征的视频数据库检索系统   总被引:2,自引:0,他引:2  
为了在视频数据库中提供有效的视频检索和浏览功能,必须建立高效的索引.由于视频数据具有层次性的结构,在镜头边界检测后,可以利用聚类方法按不同的相似性尺度对镜头关键帧进行处理,对视频数据建立索引.该系统采用颜色特征,使用Twin Comparison算法实现镜头检测和直方图平均法实现关键帧提取,对关键帧采用K均值聚类算法处理,建立视频数据库索引.实验结果表明该系统能较好地实现视频快速浏览和检索功能.  相似文献   

6.
XML is a flexible and powerful tool that enables information and security sharing in heterogeneous environments. Scalable technologies are needed to effectively manage the growing volumes of XML data. A wide variety of methods exist for storing and searching XML data; the two most common techniques are conventional tree-based and relational approaches. Tree-based approaches represent XML as a tree and use indexes and path join algorithms to process queries. In contrast, the relational approach utilizes the power of a mature relational database to store and search XML. This method relationally maps XML queries to SQL and reconstructs the XML from the database results. To date, the limited acceptance of the relational approach to XML processing is due to the need to redesign the relational schema each time a new XML hierarchy is defined. We, in contrast, describe a relational approach that is fixed schema eliminating the need for schema redesign at the expense of potentially longer runtimes. We show, however, that these potentially longer runtimes are still significantly shorter than those of the tree approach. We use a popular XML benchmark to compare the scalability of both approaches. We generated large collections of heterogeneous XML documents ranging in size from 500 MB to 8 GB using the XBench benchmark. The scalability of each method was measured by running XML queries that cover a wide range of XML search features on each collection. We measure the scalability of each method over different query features as the collection size increases. In addition, we examine the performance of each method as the result size and the number of predicates increase. Our results show that our relational approach provides a scalable approach to XML retrieval by leveraging existing relational database optimizations. Furthermore, we show that the relational approach typically outperforms the tree-based approach while scaling consistently over all collections studied.
Ophir Frieder (Corresponding author)Email:
  相似文献   

7.
The concept of mindfulness has garnered increasing attention during the last decade. Initially proposed within the scope of information systems (IS) research as a means of creating a deeper knowledge foundation for decision making regarding information technology (IT) innovations, it soon became broadly applied throughout IS research. To gain a better understanding of the evolved diversity of this concept, this paper reviews and analyzes extant IS research by means of (a) the investigated IS themes, (b) the purpose of using the concept, (c) the level of application of the concept, and (d) the tendency to focus either on mindfulness, mindlessness, or both. By synthesizing research findings, we derive a high-level IS mindfulness theory. We then propose future research opportunities, such as the explanation of the relationships between different levels of mindfulness, applying mindfulness to bridge the different phases of the software development process, and the identification of guidelines for designing information systems that facilitate mindfulness. As the first review on the application of mindfulness in IS research, we contribute to the overall understanding of mindfulness and address the four abovementioned dimensions from which mindfulness emerges in order to demonstrate that mindfulness provides a meaningful platform for generating knowledge.  相似文献   

8.
In biological research, alignment of protein sequences by computer is often needed to find similarities between them. Although results can be computed in a reasonable time for alignment of two sequences, it is still very central processing unit (CPU) time-consuming when solving massive sequences alignment problems such as protein database search. In this paper, an optimized protein database search method is presented and tested with Swiss-Prot database on graphic processing unit (GPU) devices, and further, the power of CPU multi-threaded computing is also involved to realize a GPU-based heterogeneous parallelism. In our proposed method, a hybrid alignment approach is implemented by combining Smith–Waterman local alignment algorithm with Needleman–Wunsch global alignment algorithm, and parallel database search is realized with compute unified device architecture (CUDA) parallel computing framework. In the experiment, the algorithm is tested on a lower-end and a higher-end personal computers equipped with GeForce GTX 750 Ti and GeForce GTX 1070 graphics cards, respectively. The results show that the parallel method proposed in this paper can achieve a speedup up to 138.86 times over the serial counterpart, improving efficiency and convenience of protein database search significantly.  相似文献   

9.
随着互联网技术与数据库技术的不断发展和相互结合,越来越多的用户需要访问在线数据库来获取各种信息,在该过程中,用户要对数据库中的数据进行查询。因此,用户就必需要掌握一定的结构化查询语言SQL,而且还要对数据库模式有一个认识和了解。但事实上,多数用户并不会使用结构化查询语言,也不了解数据库模式。所以,便产生了一个很自然的用户需求——数据库支持基于关键字的查询,文章主要就是对数据库支持基于关键字的查询进行简要的分析和探讨。  相似文献   

10.
刘扬 《微型机与应用》2014,(5):11-12,15
利用Visual Basic 6.0程序,设计开发了基于Access 2003数据库的辅助电极管理信息系统,以减少工作量,提高管理效率,实现锻棒和辅助电极日常管理的系统化、信息化和高效化。同时,通过查询功能,实时掌握锻棒和辅助电极库存信息,可以为合理安排生产进度提供依据。  相似文献   

11.
马光志  朱辉  龚小翔 《计算机工程与设计》2007,28(14):3367-3369,3432
分布式数据库系统中信息检索对网络状态稳定程度要求高,并不适用于P2P网络.目前的P2P数据库系统也存在通信量高,搜索计算量大等缺点.介绍了一种基于双层索引网络模型的P2P数据库的关键字搜索策略,采用双层索引模型大大减小网络通信量,同时使得在节点成员关系频繁变化的情况下也很有效.采用的关键字搜索根据相似度进行匹配,使用局部结果合并以获得更丰富的结果.  相似文献   

12.
随着Web Services技术的不断成熟和发展,存储在UDDI Registry中的Web Service信息将会变得越来越庞大,如何从UDDI Registry浩如烟海的信息资源中为用户快速、方便、准确地检索出满足需求的Web Service,将变得十分重要.而传统的基于关键词匹配的检索技术已不能满足用户准确而全面定位信息的要求.因此,以Web Service的文本描述信息为研究对象,运用文本挖掘相关方法,构建出用户概念空间,对用户提出的查询要求进行概念检索.着重介绍了用户概念空间的构建方法以及概念检索的匹配运算过程,并给出了应用于UDDI Registry的一种智能检索引擎系统模型.  相似文献   

13.
从小偷踩点获取藏金信息中受到启发,提出了一种互联网信息智能搜索新方法。能够从已经分好类的特定领域网站中,准确高效地搜索出隐藏于其内部的目标网页。把所有的搜索网页根据检索信息分成两类:一类是信息点,一类是信息路径。采用信息路径特征与信息点信息量特征描述有机结合而形成的一种新的搜索知识表示方法。基于这种知识表示方法,智能搜索方法不仅能够对网站中网页进行深度优先的智能搜索,而且还能够通过对其搜索过程和结果的自学习来获取更多更好的搜索知识。  相似文献   

14.
Cui  Wanqiu  Du  Junping  Wang  Dawei  Kou  Feifei  Liang  Meiyu  Xue  Zhe  Zhou  Nan 《World Wide Web》2019,22(6):2589-2610
World Wide Web - Searching for microblog short text by their meaning is a challenging task because of the semantic sparsity of the information in social networks. The extended search approaches are...  相似文献   

15.
《微型机与应用》2017,(6):89-91
研究了数据库检索系统的相关技术并介绍了一种基于B/S模式的数据库检索系统。系统选择H2数据库,应用B/S模式和MVC框架实现对文本、图片、声频和视频等多种数据资源的统一描述和集成管理,可对多种资源统一检索。  相似文献   

16.
研究了基于开源嵌入式数据库Derby和Java编程技术实现网上信息服务平台的方案,深入探索了Derby数据库与Java的编程接口,利用网络多连接和嵌入式连接方式、动态加载等特性,设计并实现了具有配置简单、与平台无关和高移植性的软件系统。此外,还针对实际软件系统中应用开源技术,降低系统实现成本进行了探索。  相似文献   

17.
基于XML的异构数据库信息集成的研究与实现   总被引:4,自引:0,他引:4  
文章介绍了XML技术及其特点,并将此技术运用于异构网络数据库信息集成的设计,提出了基于XML的信息系统集成体系结构,给出了基于该体系结构的一个具体实例。  相似文献   

18.
The general public is increasingly using search engines to seek information on risks and threats. Based on a search log from a large search engine, spanning three months, this study explores user patterns of query submission and subsequent clicks in sessions, for two important risk related topics, healthcare and information security, and compares them to other randomly sampled sessions. We investigate two session-level metrics reflecting users' interactivity with a search engine: session length and query click rate. Drawing from information foraging theory, we find that session length can be characterized well by the Inverse Gaussian distribution. Among three types of sessions on different topics (healthcare, information security, and other randomly sampled sessions), we find that healthcare sessions have the most queries and the highest query click rate, and information security sessions have the lowest query click rate. In addition, sessions initiated by the users with greater search engine activity level tend to have more queries and higher query click rates. Among three types of sessions, search engine activity level shows the strongest effect on query click rate for information security sessions and weakest for healthcare sessions. We discuss theoretical and practical implications of the study.  相似文献   

19.
The Semantic Web and Web services provide many opportunities in various applications such as product search and comparison in electronic commerce. We implemented an intelligent meta-search and recommendation system for products through consideration of multiple attributes by using ontology mapping and Web services. Under the assumption that each shopping site offers product ontology and product search service with Web services, we proposed a meta-search framework to configure a customer’s search intent, make and dispatch proper queries to each shopping site, evaluate search results from shopping sites, and show the customer the relevant product list with associated rankings. Ontology mapping is used for generating proper queries for shopping sites that have different product categories. We also implemented our framework and performed empirical evaluation of our approach with two leading shopping sites in the world.  相似文献   

20.
基于互信息的图像配准方法,已经广泛应用于图像配准领域.但互信息图像配准方法容易受到局部极值的干扰,难以得到最优解.对互信息图像配准中互信息的表征、图像插值方法以及优化搜索算法三个要素做了探讨,尤其针对常用的Powell搜索算法的不足,提出了基于互信息和二级搜索的图像配准算法.该算法以标准互信息为图像相似测度,利用PV插值法平滑搜索空间,采用Simplex算法进行一级粗配准,采用Powell算法进行二级精配准.仿真结果表明,二级搜索配准算法能够有效地克服局部极值,提高计算速度,用于大差异图像配准.  相似文献   

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