• Title/Summary/Keyword: Index structure

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A Multi-attribute Index for Assessing Environmental Impacts of Regional Development Projects: A Case Study of Korea (다속성 효용이론을 이용한 다속성 지수의 개발 - 지역개발에 대한 의사결정을 중심으로 -)

  • Kwak, Seung-Jun;Yoo, Seung-Hoon;Shin, Chul-Oh
    • Environmental and Resource Economics Review
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    • v.10 no.3
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    • pp.345-366
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    • 2001
  • Evaluating environmental impacts of regional development projects has critical importance in environmental management aspect. This paper uses multi-attribute utility theory as a basis for obtaining a value index to assess the environmental impacts and applies the theory to a specific Korean case study. To structure and quantify basic values for the assessment, we elicited important attributes, then refined and structured them into a hierarchy. An environmental multi-attribute index is constructed as a multi-attribute utility function, based on value judgments provided by a group of technical experts, policy makers, and a decision-maker at Korean Ministry of Environment. The implications of the results are also discussed. We found that the work and results can provide valuable insights for assessment of environmental consequences.

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Distributed Indexing Methods for Moving Objects based on Spark Stream

  • Lee, Yunsou;Song, Seokil
    • International Journal of Contents
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    • v.11 no.1
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    • pp.69-72
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    • 2015
  • Generally, existing parallel main-memory spatial index structures to avoid the trade-off between query freshness and CPU cost uses light-weight locking techniques. However, still, the lock based methods have some limits such as thrashing which is a well-known problem in lock based methods. In this paper, we propose a distributed index structure for moving objects exploiting the parallelism in multiple machines. The proposed index is a lock free multi-version concurrency technique based on the D-Stream model of Spark Stream. The proposed method exploits the multiversion nature of D-Stream of Spark Streaming.

Robust Discrete-Time Observer Design (강인한 이산관측기 설계)

  • 허건수;김상진
    • Journal of the Korean Society for Precision Engineering
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    • v.15 no.4
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    • pp.134-140
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    • 1998
  • The authors have shown that the performance of discrete-time observer-based monitoring systems can be represented by the performance index k$_2$(P) (condition number of the eigensystem P of the observer matrix in terms of L$_2$ norm). The observers with the minimized performance index can be defined as robust observers in the sense that the observer performance can be guaranteed in harsh environments. In this paper, based on the performance index, a design methodology for the robust discrete-time observer is developed. Similar to the continuous-time case, the methodology determines the structure and eigenvalues of the observer matrix simultaneously. A complete design procedure is given for single-output case and is illustrated with a spindle-driver example. The simulation results demonstrate the improved performance compared with a traditional pole-placement observer technique.

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Bit-map Indexes and Their Selection Problem for Efficient Processing of Star Joins in Object Databases (객체 데이터베이스에서 스타 조인의 빠른처리를 위한 비트맵 색인 기법과 그의 선정 문제)

  • 조완섭;정태성;이현철;장혜경;안명상
    • Journal of Information Technology Applications and Management
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    • v.10 no.2
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    • pp.19-31
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    • 2003
  • We propose an indexing technique and an index selection algorithm for optimal OLAP query processing in object database systems, Although there are many research results on the relational database systems for OLAP Query processing, few researches have been done on the object database systems. Since OLAP queries represent complex business logic on a huge data ware-house, object database systems supporting the OLAP queries should have higher performance. Proposed bitmap index structure is an extension of conventional bitmap indexes for adapting object databases and provides higher performance with lower space overhead. We also propose a linear time solution of the index selection problem that will be used in the OLAP query optimization process.

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Analysis of the Ability of Recognize Objects for Smart Sensor According to Frequency Changing (주파수 변화에 따른 지적센서의 대상물 인식능력 분석)

  • 황성연;홍동표;강희용;박준홍
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2000.11a
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    • pp.23-26
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    • 2000
  • This paper descrtbcs our prlmary study for a new mncthod of recogninng materials. which is need for precision work system. This IS a study of dynarnlc characteristics of sensor. new melhod ($R_{SAI}$) has thc sensing ability of distinguishing materials. Experiment and annlysis are executed for proper dynamic scnslng condition. First. we developed advanced smart sensor Second, we develop new methods that have a sensing ability of distinguish matarialsAccording to frequency changing. mtluence of smart sensor are evaluated through new recognition Index ($R_{SAI}$) that ratioof sensing ability index. Disungush of object is cxucuted wllh RsA, method relalivcly according to liequency changing. Wecan use the RsAl for finding materids. Applfciltionr of thls method are linding abnormal condition of obicct (automanufacturing).keling ofobject (medlcal product). tobolics, safety diagnosis of structure, etc

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A study on Reliability Analysis for Plane Frame Structure (평면뼈대구조의 신뢰성해석에 관한연구)

  • 이중빈;신형우
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 1989.10a
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    • pp.34-39
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    • 1989
  • Recent trends in design standards development have encouraged the use of probabilistic limit sate design concepts. Reliability analysis adopted in those advanced countries have the potentials that they afford for symplifying the design Process arid placing it on a consistent reliability based for various construction materials. This study is proposed in the reliability analysis of plane frame structures using second-order moment method(Level-II they). Lind-Hasofer's minimum distance method is use in the derivation of an mathematical algorithm as well as an determination of Correlation cofficients, reliability index and total reliability index depending on the multiple failure modes. In addition. This study is employed as a practical tool for the approximate reliability analysis. Results of the numerincal analysis showed that the difference between the reliability index of the failure probability of the multiple failure modes and the total reliability index of the failure probability with the simultaneous failure modes deviated nearly 3∼10% depending on tile performance functions.

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Evaluation of Competitiveness in Auto Distribution Industry between Korea and Russia

  • Lee, Jae-Sung
    • Journal of Distribution Science
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    • v.13 no.8
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    • pp.5-14
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    • 2015
  • Purpose - This study undertakes to examine the automotive trade structure between Korea and Russia to accelerate economic cooperation and pinpoint trade discrepancies to increase trade volume through improved policies, eventually finding ways for trade expansion. Research design, data, and methodology - To analyze trade decision factors for both countries, the Index of trade specialization invented by trade specialization theory, is used. Although specific factors should materialize in the trade decision analysis, realistically, concrete explanations are difficult as many unsolved factors are involved as well as their complexities Results - First, to assess comparative market competitiveness, the Index describes A value/B value, representing the Korean versus the Russia market share and the Korean market share versus the world. Second, the index shows that Korea is taking comparative advantage of its export specialization. Third, the RCA indices show considerable improvement compared to 2000. Conclusions - This research used a quantitative approach to examine trade specialization and examined a comparative advantage index of market share to see how inter-trade relations have changed over the past 10 years.

Robust Design of Structural and Mechanical Systems using Concept of Allowable Load Set (허용하중집합 개념을 이용한 기계/구조 시스템의 강건 설계)

  • Kwak, Byung-Man
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2007.04a
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    • pp.333-338
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    • 2007
  • The concept of "Allowable Load Set (ALS)" introduced by the author allows an easy understanding of load and strength characteristics of a structure in relation to its integrity under uncertainties. Two criteria of safety are introduced: A relative safety index denotes the distance to the boundary of the ALS and a normalized safety index is a distance in terms of functional value. They have been utilized in several examples, including multi-body mechanical systems such as a biomechanical system. Both formulations amount to robust designs in the sense that designs most insensitive to uncertainties are obtained in the context of newly defined safety indices, without using any input probability information.

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A Multi-attribute Index for Evaluating of National Nuclear R&D Projects: A Case Study of Korea (다속성 효용이론을 이용한 평가지표개발 - 원자력연구개발사업의 사후평가를 중심으로 -)

  • 곽승준;유승훈;김찬준
    • Proceedings of the Korea Technology Innovation Society Conference
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    • 2001.05a
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    • pp.389-408
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    • 2001
  • Evaluating the results of National Nuclear R&D projects has critical importance in nuclear management aspect. This paper uses multi-attribute utility theory as a basis for obtaining a value Index to assess the results of nuclear R&D projects and applies the theory to a specific Korean case study. To structure and quantify basic values for the . evaluation, we elicited important attributes, then refined and structured them into a hierarchy. A multi-attribute index is constructed as a multi-attribute utility function, based on value judgments provided by a group of technical experts, policy makers, and decision-makers. The implications of the results are also discussed. We found that the work and results can provide valuable insights for assessment of nuclear R&D consequences.

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The Studies in Relationship between Molecular Structure and Biological Activities (생리활성과 분자구조의 상관관계에 관한 연구)

  • Kim Ui-Rak;Min Kyung-Sub;Kim Joung-Too;Jeong Bong-Jin
    • Journal of the Korean Chemical Society
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    • v.37 no.1
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    • pp.68-75
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    • 1993
  • Various biological activities (enzyme inhibitory potency, lipoxygenase inhibition, tadpole narcosis, vapor toxicity and heat of vaporization) of molecules are correlated with molecular descriptors. The molecular descriptors used in this works are molecular connectivity index, Wiener distance index and ad hoc descriptor, which can encode information about branching, size, cyclization, unsaturation, hetero atom content and polarizability. It is found that calculated values from multiple regression equations are in a good agreement with experimental data on five biological activities of alcohol, ester and ketone compounds.

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