• Title/Summary/Keyword: Index기법

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Correlation Analysis between Soil Shear Strength Parameters and Cone Index Using Artificial Neural Networks - 1 (인공신경망을 적용한 지반 전단강도정수와 콘지수 사이의 상관관계 분석 1)

  • Moon, In-Jong;Kim, Young-Uk
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.16 no.3
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    • pp.2234-2241
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    • 2015
  • This study has been undertaken to develop a relationship between the shear strength coefficients and the cone index. The theoretic mathematical equations for the relationship were rigorously investigated, and then a Artificial Neural Network(ANN) analysis was adapted to enhance the reliability of the investigation. The theoretical investigation involved various assumptions resulting in the significant error involvement of geotechnical behaviors of ground. Therefore, a model using the ANN has been learned to enhance the prediction of the cone index form the shear strength parameters. Site investigation reports from various construction fields were used for ANN model learning. The results of the study show that the model predicts the cone index from the shear strength parameters of soils very well. The further study that is undertaking has a potential promise of the generalized prediction technique for the cone index from the soil parameters.

An Efficient Inverted Index Technique based on RDBMS for XML Documents (XML 문서에 대한 RDBMS에 기반을 둔 효율적인 역색인 기법)

  • 서치영;이상원;김형주
    • Journal of KIISE:Databases
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    • v.30 no.1
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    • pp.27-40
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    • 2003
  • The inverted index widely used in the existing information retrieval field should be extended for XML documents to support containment queries by XML information retrieval systems. In this paper, we consider that there are two methods in storing the inverted index and processing containment queries for XML documents as the previous work suggested: using a RDBMS or using an inverted lift engine. It has two drawbacks to extend the inverted index in the previous work. One is that using a RDBMS is moth worse in the performance than using an inverted list engine. The other is that when containment queries are processed in a RDBMS, there is an increase in the number of a join operation as the path length of a query increases and a join operation always happens between large fables. In this paper. we extend the inverted index in a different way to solve these problems and show the effectiveness of using a RDBMS.

Determining the Number of Risk Level Using Real-time Sensitivities in the Probabilistic Maritime Risk Evaluation (확률기반 해상위기평가에서 실시간 민감도를 이용한 위기수준의 단계 구분 수 결정에 관한 연구)

  • Gang, Sang-Guen
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.20 no.6
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    • pp.685-691
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    • 2014
  • The result of probabilistic maritime risk evaluation is represented by the probability(P=0.0~1.0) These results are shown by an index using Risk Acceptance Criteria(RAC) to base the evaluation generally to know the risk level easily. Current RAC is divided into 3 steps, 5 steps, 7 steps, etc. Despite need to evaluate whether the number of RAC for risk evaluation is reasonable, there is not a related research yet. In this study, It was proposed the evaluation method to determine the optimum index number of RAC using the Sensitivity distribution characteristics and the Sensitivity by the index number of RAC. As application result from the proposed method for probabilistic risk evaluation data obtained from the prior studies, It could be determined the optimum index number of RAC by Sensitivity below 10 times and confirmed that the proposed method is reasonable by this study.

Index management technique using Small block in storage device based on NAND flash memory

  • Lee, Seung-Woo;Oh, Se-Jin
    • Journal of the Korea Society of Computer and Information
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    • v.25 no.10
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    • pp.1-14
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    • 2020
  • In this paper, we propose to solve the problem of increasing system memory usage due to an increase in the number of mapping information management when using a NAND flash memory-based storage device in an existing sector-based file system. The proposed technique is to store only mapping information in page units based on index blocks and manage them in block units. To this end, the proposed technique uses a sequential offset for storing and managing a plurality of mapping information in one page in a small block, and a reverse offset for a spare page corresponding to a change in mapping information in the block. Through this, the proposed technique has the advantage that the number of block-unit deletions is less than that of the existing technique, and the system memory usage required for mapping information management is low. Reduced by about 32%.

Bit-Map Based Hybrid Fast IP Lookup Technique (비트-맵 기반의 혼합형 고속 IP 검색 기법)

  • Oh Seung-Hyun
    • Journal of Korea Multimedia Society
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    • v.9 no.2
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    • pp.244-254
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    • 2006
  • This paper presents an efficient hybrid technique to compact the trie indexing the huge forward table small enough to be stored into cache for speeding up IP lookup. It combines two techniques, an encoding scheme called bit-map and a controlled-prefix expanding scheme to replace slow memory search with few fast-memory accesses and computations. For compaction, the bit-map represents each index and child pointer with one bit respectively. For example, when one node denotes n bits, the bit-map gives a high compression rate by consumes $2^{n-1}$ bits for $2^n$ index and child link pointers branched out of the node. The controlled-prefix expanding scheme determines the number of address bits represented by all root node of each trie's level. At this time, controlled-prefix scheme use a dynamic programming technique to get a smallest trie memory size with given number of trie's level. This paper proposes standard that can choose suitable trie structure depending on memory size of system and the required IP lookup speed presenting optimal memory size and the lookup speed according to trie level number.

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An Effective Path Table Method Exploiting the Region Numbering Technique (영역 할당 기법을 이용한 효율적인 경로 테이블 기법)

  • Min Jun-Ki
    • The KIPS Transactions:PartD
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    • v.13D no.2 s.105
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    • pp.157-164
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    • 2006
  • Since XML is emerging as the de facto standard for exchanging and representation of data on the web, the amount of XML data has rapidly increased. Thus, the need for effective store and retrieval of U data has arisen. Since the existing techniques such as XRel which is an XML storage and management technique using RDBMS simply record the existing all label paths, diverse classes of label path expressions could not be efficiently supported. In this paper, we present a technique which supports storage and retrieval for XML data using RDBMS efficiently compared with the existing approaches. Since the proposed technique keeps the XML path index on the relational database and replace label paths with path identifiers, diverse XML queries can be evaluated compared with existing approaches. Also, the proposed technique does not require the modification of the relational database engine and consumes the disk space less. Our experimental result demonstrates the better query performance compared with existing techniques.

Pansharpening Method for KOMPSAT-2/3 High-Spatial Resolution Satellite Image (아리랑 2/3호 고해상도 위성영상에 적합한 융합기법)

  • Oh, Kwan-Young;Jung, Hyung-Sup;Jeong, Nam-Ki
    • Korean Journal of Remote Sensing
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    • v.31 no.2
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    • pp.161-170
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    • 2015
  • This paper presents an efficient image fusion method to be appropriate for the KOMPSAT-2 and 3 satellites. The proposed method is based on the well-established component substitution (CS) approach. The proposed method is divided into two parts: 1) The first step is to create a intensity image by the weighted-averaging operation of a multi-spectral (MS) image and 2) the second step is to produce an optimal high-frequency image using the statistical properties of the original MS and panchromatic (PAN) images. The performance of the proposed method is evaluated in both quantitative and visual analysis. Quantitative assessments are performed by using the relative global dimensional synthesis error (Spatial and Spectral ERGAS), the image quality index (Q4), and the spectral angle mapper index (SAM). The qualitative and quantitative assessment results show that the fusion performance of the proposed method is improved in both the spectral and spatial qualities when it is compared with previous CS-based fusion methods.

Efficient Structural Join Technique using the Level Information of Indexed XML Documents (색인된 XML 문서에서 레벨 정보를 이용한 효과적인 구조 조인 기법)

  • Lee Yunho;Choi Ilhwan;Kim Jongik;Kim Hyoung-Joo
    • Journal of KIISE:Databases
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    • v.32 no.6
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    • pp.641-649
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    • 2005
  • As XML is widely used with the development of internet, many researches on the XML storage and query processing have been done Several index techniques have been proposed to efficiently process XML path queries. Recently, structural join has received murk attention as a method to protest the path query. Structural join technique process a path query by identifying the containment relationship of elements. Especially, it has an advantage that we can get the result set by simply comparing related elements only instead of scanning whole document. However during the comparison process, unnecessary elements that are not included in the result set can be scanned. So we propose a new technique, the level structural join. In this technique, we use both the relationship and the level distribution of elements in the path query. Using this technique, we tao improve the performance of query processing only by comparing elements with specific level in the target inverted level.