• Title/Summary/Keyword: Query Compilation

Search Result 5, Processing Time 0.018 seconds

Performance Evaluation of System Catalog Management Schemes for Distributed XML Repository Systems at the Query Compilation Time (분산 XML 저장 시스템에서 질의 컴파일 시 시스템 카탈로그 관리 기법의 성능 평가)

  • Jang, Gun-Up;Hong, Eui-Kyeong
    • Journal of Korea Multimedia Society
    • /
    • v.12 no.2
    • /
    • pp.178-190
    • /
    • 2009
  • XML is recommended by W3C(World Wide Web) and widely accepted as a standard markup language for expression and sharing data. Recently, increasing the use and the amount of XML documents, there is required that easy methods for accessing XML documents at anytime and anywhere, therefore, the distributed XML repository systems is developed. For this, distributed XML repository systems is necessary to research catalog management schemes. In this paper, we design distributed XML database model considering CPU costs, I/O costs, concurrency control, two-phase commits a protocol, queuing delay and so on. And we implement a simulator in order to execute performance evaluation centralized catalog method, fully replicated catalog method, and partitioned catalog method using reasonably setting up environments.

  • PDF

Pre-Processing of Query Logs in Web Usage Mining

  • Abdullah, Norhaiza Ya;Husin, Husna Sarirah;Ramadhani, Herny;Nadarajan, Shanmuga Vivekanada
    • Industrial Engineering and Management Systems
    • /
    • v.11 no.1
    • /
    • pp.82-86
    • /
    • 2012
  • In For the past few years, query log data has been collected to find user's behavior in using the site. Many researches have studied on the usage of query logs to extract user's preference, recommend personalization, improve caching and pre-fetching of Web objects, build better adaptive user interfaces, and also to improve Web search for a search engine application. A query log contain data such as the client's IP address, time and date of request, the resources or page requested, status of request HTTP method used and the type of browser and operating system. A query log can offer valuable insight into web site usage. A proper compilation and interpretation of query log can provide a baseline of statistics that indicate the usage levels of website and can be used as tool to assist decision making in management activities. In this paper we want to discuss on the tasks performed of query logs in pre-processing of web usage mining. We will use query logs from an online newspaper company. The query logs will undergo pre-processing stage, in which the clickstream data is cleaned and partitioned into a set of user interactions which will represent the activities of each user during their visits to the site. The query logs will undergo essential task in pre-processing which are data cleaning and user identification.

Contents Analysis and Synthesis Scheme for Music Album Cover Art

  • Moon, Dae-Jin;Rho, Seung-Min;Hwang, Een-Jun
    • Journal of IKEEE
    • /
    • v.14 no.4
    • /
    • pp.305-311
    • /
    • 2010
  • Most recent web search engines perform effective keyword-based multimedia contents retrieval by investigating keywords associated with multimedia contents on the Web and comparing them with query keywords. On the other hand, most music and compilation albums provide professional artwork as cover art that will be displayed when the music is played. If the cover art is not available, then the music player just displays some dummy or random images, but this has been a source of dissatisfaction. In this paper, in order to automatically create cover art that is matched with music contents, we propose a music album cover art creation scheme based on music contents analysis and result synthesis. We first (i) analyze music contents and their lyrics and extract representative keywords, (ii) expand the keywords using WordNet and generate various queries, (iii) retrieve related images from the Web using those queries, and finally (iv) synthesize them according to the user preference for album cover art. To show the effectiveness of our scheme, we developed a prototype system and reported some results.

Performance Evaluation of Catalog Management Schemes for Distributed Main Memory Databases (분산 주기억장치 데이터베이스에서 카탈로그 관리 기법의 성능평가)

  • Jeong, Han-Ra;Hong, Eui-Kyeong;Kim, Myung
    • Journal of Korea Multimedia Society
    • /
    • v.8 no.4
    • /
    • pp.439-449
    • /
    • 2005
  • Distributed main memory database management systems (DMM-DBMSs) store the database in main memories of the participating sites. They provide high performance through fast access to the local databases and high speed communication among the sites. Recently, a lot of research results on DMM- DBMSs has been reported. However, to the best of our knowledge, there is no known research result on the performance of the catalog management schemes for DMM-DBMSs. In this work, we evaluated the performance of the partitioned catalog management schemes through experimental analysis. First, we classified the partitioned catalog management schemes into three categories : Partitioned Catalogs Without Caching (PCWC), Partitioned Catalogs With Incremental Caching (PCWIC), and Partitioned Catalogs With Full Caching (PCWFC). Experiments were conducted by varying the number of sites, the number of terminals per site, buffer size, write query ratio, and local query ratio. Experiments show that PCWFC outperforms the other two schemes in all cases. It also means that the performance of PCWIC gradually increases as time goes by. It should be noted that PCWFC does not guarantee high performance for disk-based distributed DBMSs in cases when the workload of individual site is high, catalog write ratio is high, or remote data objects are accessed very frequently. Main reason that PCWFC outperforms for DMM-DBMSs is that query compilation and remote catalog access can be done in a very high speed, even when the catalogs of the remote data objects are frequently updated.

  • PDF

Development of the conventional crop composition database for new genetically engineered crop safety assessment (새로운 생명공학작물 안전성 평가를 위한 작물 성분 DB 구축)

  • Kim, Eun-Ha;Lee, Seong-Kon;Park, Soo-Yun;Lee, Sang-Gu;Oh, Seon-Woo
    • Journal of Plant Biotechnology
    • /
    • v.45 no.4
    • /
    • pp.289-298
    • /
    • 2018
  • The Biosafety Division of the National Academy of Agricultural Science has developed a 'Crop Composition DB' that provides analytical data on commercialized crops. It can be used as a reference in the 'Comparative Evaluation by Compositional Analysis' for the safety assessment of genetically modified (GM) crops. This database provides the composition of crops cultivated in Korea, and thus upgrades the data to check the extent of changes in the compositional content depending on the cultivated area, varieties and year. The database is a compilation of data on the antioxidant, nutrient and secondary metabolite compositions of rice and capsicum grown in two or more cultivation areas for a period of more than two years. Data analysis was conducted under the guidelines of the Association of Official Analytical Chemists or methods previously reported on papers. The data was provided as average, minimum and maximum values to assess whether the statistical differences between the GM crops and comparative non-GM crops fall within the biological differences or tolerances of the existing commercial crops. The Crop Composition DB is an open-access source and is easy to access based on the query selected by the user. Moreover, functional ingredients of colored crops, such as potatoes, sweet potatoes and cauliflowers, were provided so that food information can be used and utilized by general consumers. This paper introduces the feature and usage of 'Crop Composition DB', which is a valuable tool for characterizing the composition of conventional crops.