• Title/Summary/Keyword: 테이블

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The Bit-Map Trip Structure for Giga-Bit Forwarding Lookup in High-Speed Routers (고속 라우터의 기가비트 포워딩 검색을 위한 비트-맵 트라이 구조)

  • Oh, Seung-Hyun;Ahn, Jong-Suk
    • Journal of KIISE:Information Networking
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    • v.28 no.2
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    • pp.262-276
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    • 2001
  • Recently much research for developing forwarding table that support fast router without employing both special hardware and new protocols. This article introduces a new forwarding data structure based on the software to enable forwarding lookup to be penormed at giga-bit speed. The forwarding table is known as a bottleneck of the routers penormance due to its high complexity proportional to the forwarding table size. The recent research that based on the software uses a Patricia trie and its variants. and also uses a hash function with prefix length key and others. The proposed forwarding table structure construct a forwarding table by the bit stream array in which it constructs trie from routing table prefix entries and it represents each pointer pointing the child node and the associated forwarding table entry with one bit The trie structure and routing prefix pointer need a large memory when representing those by linked-list or array. but in the proposed data structure, the needed memory size is small enough since it represents information with one bit. Additionally, by use a lookup method that start searching at desired middle level we can shorten the search path. The introduced data structure. called bit-map trie shows that we can implement a fast forwarding engine on the conventional Pentium processor by reducing the backbone routing table fits into Level 2 cache of Pentium II processor and shortens the searching path. Our experiments to evaluate the performance of proposed method show that this bit-map trie accomplishes 5.7 million lookups per second.

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Evaluation of Accuracy About 2D vs 3D Real-Time Position Management System Based on Couch Rotation when non-Coplanar Respiratory Gated Radiation Therapy (비동일평면 호흡동조방사선치료 시 테이블 회전에 따른 2D vs 3D Real-Time Position Management 시스템의 정확성 평가)

  • Kwon, Kyung-Tae;Kim, Jung-Soo;Sim, Hyun-Sun;Min, Jung-Whan;Son, Soon-Yong;Han, Dong-Kyoon
    • Journal of radiological science and technology
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    • v.39 no.4
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    • pp.601-606
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    • 2016
  • Because of non-coplanar therapy with couch rotation in respiratory gated radiation therapy, the recognition of marker movement due to the change in the distance between the infrared camera and the marker due to the rotation of the couch is called RPM (Real-time The purpose of this paper is to evaluate the accuracy of motion reflections (baseline changes) of 2D gating configuration (two dot marker block) and 3D gating configuration (six dot marker block). The motion was measured by varying the couch angle in the clockwise and counterclockwise directions by $10^{\circ}$ in the 2D gating configuration. In the 3D gating configuration, the couch angle was changed by $10^{\circ}$ in the clockwise direction and compared with the baseline at the reference $0^{\circ}$. The reference amplitude was 1.173 to 1.165, the couch angle at $20^{\circ}$ was 1.132, and the couch angle at $1.0^{\circ}$ was 1.083. At $350^{\circ}$ counterclockwise, the reference amplitude was 1.168 to 1.157, the couch angle at $340^{\circ}$ was 1.124, and the couch angle at $330^{\circ}$ was 1.079. In this study, the phantom is used to quantitatively evaluate the value of the amplitude according to couch change.

A PIVOT based Query Optimization Technique for Horizontal View Tables in Relational Databases (관계 데이터베이스에서 수평 뷰 테이블에 대한 PIVOT 기반의 질의 최적화 방법)

  • Shin, Sung-Hyun;Moon, Yang-Sae;Kim, Jin-Ho;Kang, Gong-Mi
    • The KIPS Transactions:PartD
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    • v.14D no.2
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    • pp.157-168
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    • 2007
  • For effective analyses in various business applications, OLAP(On-Line Analytical Processing) systems represent the multidimensional data as the horizontal format of tables whose columns are corresponding to values of dimension attributes. Because the traditional RDBMSs have the limitation on the maximum number of attributes in table columns(MS SQLServer and Oracle permit each table to have up to 1,024 columns), horizontal tables cannot be directly stored into relational database systems. In this paper, we propose various efficient optimization strategies in transforming horizontal queries to equivalent vertical queries. To achieve this goral, we first store a horizontal table using an equivalent vertical table, and then develop various query transformation rules for horizontal table queries using the PIVOT operator. In particular, we propose various alternative query transformation rules for the basic relational operators, selection, projection, and join. Here, we note that the transformed queries can be executed in several ways, and their execution times will differ from each other. Thus, we propose various optimization strategies that transform the horizontal queries to the equivalent vertical queries when using the PIVOT operator. Finally, we evaluate these methods through extensive experiments and identify the optimal transformation strategy when using the PIVOT operator.

Survey: The Tabletop Display Techniques for Collaborative Interaction (협력적인 상호작용을 위한 테이블-탑 디스플레이 기술 동향)

  • Kim, Song-Gook;Lee, Chil-Woo
    • Proceedings of the Korea Contents Association Conference
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    • 2006.11a
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    • pp.616-621
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    • 2006
  • Recently, the researches based on vision about user attention and action awareness are being pushed actively for human computer interaction. Among them, various applications of tabletop display system are developed more in accordance with touch sensing technique, co-located and collaborative work. Formerly, although supported only one user, support multi-user at present. Therefore, collaborative work and interaction of four elements (human, computer, displayed objects, physical objects) that is ultimate goal of tabletop display are realizable. Generally, tabletop display system designs according to four key aspects. 1)multi-touch interaction using bare hands. 2)implementation of collaborative work, simultaneous user interaction. 3)direct touch interaction. 4)use of physical objects as an interaction tool. In this paper, we describe a critical analysis of the state-of-the-art in advanced multi-touch sensing techniques for tabletop display system according to the four methods: vision based method, non-vision based method, top-down projection system and rear projection system. And we also discuss some problems and practical applications in the research field.

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A Study of Requirement Change Management and Traceability Effect Using Traceability Table (추적테이블을 이용한 요구사항 변경관리 및 추적 효과 연구)

  • Kim, Ju-Young;Rhew, Sung-Yul;Hwang, Man-Su
    • The KIPS Transactions:PartD
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    • v.17D no.4
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    • pp.271-282
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    • 2010
  • Insufficient requirement management accounts for 54% ofunsuccessful software development projects and 22% of insufficient requirement management comes from requirement change management. Hence, requirement management activities are important to reduce failure rates and a tracing method is suggested as the major factor in requirements change management. A traceability table is easy to use because of its legibility accurate tracing. However, traceability tables of existing studies have failed to concretely suggest method of change management and effect of traceability. Also, studies of methods to estimate change impact is complex. Hence, this study suggests how to use a traceability table to manage changes in requirements. Together, in comparison to existing studies, this study suggests easier methods to estimate change rate and change impact. Also Fifteen projects were sampled to test the hypothesis that traceability table influences the success of projects and that it decreases the failure rate that comes from the insufficient requirements management.

An Efficient Algorithm for Detecting Tables in HTML Documents (HTML 문서의 테이블 식별을 위한 효율적인 알고리즘)

  • Kim Yeon-Seok;Lee Kyong-Ho
    • Journal of Korea Multimedia Society
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    • v.7 no.10
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    • pp.1339-1353
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    • 2004
  • < TABLE > tags in HTML documents are widely used for formatting layout of Web documents as well as for describing genuine tables with relational information. As a prerequisite for information extraction from the Web, this paper presents an efficient method for sophisticated table detection. The proposed method consists of two phases: preprocessing and attribute-value relations extraction. For the preprocessing where genuine or ungenuine tables are filtered out, appropriate rules are devised based on a careful examination of general characteristics of < TABLE > tags. The remaining is detected at the attribute-value relations extraction phase. Specifically, a value area is extracted and checked out whether there is a syntactic coherency Futhermore, the method looks for a semantic coherency between an attribute area and a value area of a table that may be inappropriate for the syntactic coherency checkup. Experimental results with 11,477 < TABLE > tags from 1,393 HTML documents show at the method has performed better compared with previous works, resulting in a precision of 97.54% and a recall of 99.22% in average.

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An Efficient Method for Logical Structure Analysis of HTML Tables (HTML 테이블의 논리적 구조분석을 위한 효율적인 방법)

  • Kim Yeon-Seok;Lee Kyong-Ho
    • Journal of Korea Multimedia Society
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    • v.9 no.9
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    • pp.1231-1246
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    • 2006
  • HTML is a format for rendering Web documents visually and uses tables to present a relational information. Since HTML has limits in terms of information processing and management by a computer, it is important to transform HTML tables into XML documents, which is able to represent logical structure information. As a prerequisite for extracting information from the Web, this paper presents an efficient method for extracting logical structures from HTML tables and transforming them into XML documents. The proposed method consists of two phases: Area segmentation and structure analysis. The area segmentation step removes noisy areas and extracts attribute and value areas through visual and semantic coherency checkup. The hierarchical structure between attribute and value areas are analyzed and transformed into XML representations using a proposed table model. Experimental results with 1,180 HTML tables show that the proposed method performs better than the conventional method, resulting in an average precision of 86.7%.

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An Empirical Study on Tracking Table for Consistency and Completeness Validation in the Outputs (산출물의 일관성과 완전성 검증을 위한 추적테이블의 경험적 연구)

  • Kim, Ju-Young;Rhew, Sung-Yul
    • Journal of KIISE:Software and Applications
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    • v.34 no.5
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    • pp.419-430
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    • 2007
  • It is very important to track whether software is properly developed according to requirements. This study suggests a method to track requirements by using a tracking table. In this study, the tracking table indicates why such requirements are included by detailing the content of requests for proposals and proposals. The table also facilitates verification of the consistency between outputs and the integrity by having ID codes of each requirement mapped to each output. Furthermore, as this study was conducted, it was found that some factors were required to be added or supplemented to the outputs at the requirement gathering stage of MaRMI-Ⅲ v.4.0 methodology. Thus, this study seeks to present this additional result along with the enhanced tracking table. By verifying outputs, the tracking table presented in this study will help to reduce all kinds of risks and problems that may occur in software development due to the lack of management of requirements. In addition, the output of the requirement-gathering stage of MaRMI-Ⅲ v.4.0 methodology will be improved/supplemented according to the creation of tracking tables; this will increment the applicability of the MaRMI-III methodology.

A General-Purpose Service Information Processing System for Integrated Data Broadcasting Environment (통합 데이터 방송 환경을 위한 범용 서비스 인포메이션 처리 시스템)

  • Jeon, Je-Min;Choi, Hyeon-Seok;Kim, Jung-Sun
    • The KIPS Transactions:PartC
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    • v.16C no.1
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    • pp.101-108
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    • 2009
  • The data broadcasting service, which is growing remarkably today, provides viewers with useful information as well as high quality video and audio. Service information is a kind of additional data that contains a wide range of information such as channel list and/or program title. Each service information is transmitted in the form of a table. And most standard committees have specified their own table list used for carrying the service information. Consequently, It causes incompatibility among services that each broadcast operators produce because the tables that they use differ from each other. In this paper, we propose a general-purpose service information processing system for an integrated data broadcasting middleware that is compatible with heterogenous broadcasting environments. The system is able to change its target table list dynamically without any code modification. Futhermore, we also adopted a thread pool model for efficient parsing and event dispatching.

Real-Time Color Gamut Mapping Method Based on the Three-Dimensional Difference Look-Up Table (3차원 차분 룩업 테이블을 이용한 실시간 색역 사상 기법)

  • Han, Dong-Il
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.42 no.6
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    • pp.111-120
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    • 2005
  • A cost effective three-dimensional color gamut mapping architecture is described. The conventional three-dimensional reduced resolution look-up table is considered and the concept of three-dimensional reduced resolution difference look-up table is introduced for cost effective and real-time color gamut mapping. The overall architecture uses one-dimensional memory decomposition of three-dimensional gamut mapping look-up table, three-dimensional interpolation and simple addition operation for generating the final gamut mapped colors. The required computational cost is greatly reduced by look-up table resolution adjustment and further reduced by the gamut mapping rule modification. The proposed architecture greatly reduces the required memory size and hardware complexity compared to the conventional method and it is suitable for real-time applications. The proposed hardware is suitable for FPGA and ASIC implementation and could be applied to the real-time display quality enhancement purposes.