• Title/Summary/Keyword: R+-트리

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An Extended R-Tree Indexing Method using Prefetching in Main Memory (메인 메모리에서 선반입을 사용한 확장된 R-Tree 색인 기법)

  • Kang, Hong-Koo;Kim, Dong-O;Hong, Dong-Sook;Han, Ki-Joon
    • Journal of Korea Spatial Information System Society
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    • v.6 no.1 s.11
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    • pp.19-29
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    • 2004
  • Recently, studies have been performed to improve the cache performance of the R-Tree in main memory. A general mothed to improve the cache performance of the R-Tree is to reduce size of an entry so that a node can store more entries and fanout of it can increase. However, this method generally requites additional process to reduce information of entries and do not support incremental updates. In addition, the cache miss always occurs on moving between a parent node and a child node. To solve these problems efficiently, this paper proposes and evaluates the PR-Tree that is an extended R-Tree indexing method using prefetching in main memory. The PR-Tree can produce a wider node to optimize prefetching without additional modifications on the R-Tree. Moreover, the PR-Tree reduces cache miss rates that occur in moving between a parent node and a child node. In our simulation, the search performance, the update performance, and the node split performance of the PR-Tree improve up to 38%. 30%, and 67% respectively, compared with the original R-Tree.

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MLR-tree : Spatial Indexing Method for Window Query of Multi-Level Geographic Data (MLR 트리 : 다중 레벨 지리정보 데이터의 윈도우 질의를 위한 공간 인덱싱 기법)

  • 권준희;윤용익
    • Journal of KIISE:Databases
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    • v.30 no.5
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    • pp.521-531
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    • 2003
  • Multi-level geographic data can be mainpulated by a window query such as a zoom operation. In order to handle multi-level geographic data efficiently, a spatial indexing method supporting a window query is needed. However, the conventional spatial indexing methods are not efficient to access multi-level geographic data quickly. To solve it, other a few spatial indexing methods for multi-level geographic data are known. However these methods do not support all types of multi-level geographic data. This paper presents a new efficient spatial indexing method, the MLR-tree for window query of multi-level geographic data. The MLR-tree offers both high search performance and no data redundancy. Experiments show them. Moreover, the MLR-tree supports all types of multi-level geographic data.

Strategy Implications on R&D of New Medicine through Technology Valuation (의사결정트리를 통한 신약개발의 가치평가와 R&D 전략 시사점)

  • Park, Hyeon-U
    • Journal of Korea Technology Innovation Society
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    • v.8 no.1
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    • pp.94-115
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    • 2005
  • The purpose of this study is to evaluate the economic value of a biotechnology in the middle of R&D and to examine strategies to manage a variety of risks and uncertainties intrinsic in research and development of biotechnologies through economic valuation in consideration of technological and industrial characteristics of the technology. To do this, this study analyzes the probability of commercial success of the technology development in qualitative terms, evaluates the quantitative value of the technology on the basis of a determined model, and proposes the implications on R&D strategy. In concrete, this study analyzes the economic value of the technology by constructing a decision tree reflecting the characteristics of the R&D process of the technology and draw the implications on the future R&D strategies of the technology.

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VP Filtering for Efficient Query Processing in R-tree Variants Index Structures (R-tree 계열의 인덱싱 구조에서의 효율적 질의 처리를 위한 VP 필터링)

  • Kim, Byung-Gon;Lee, Jae-Ho;Lim, Hae-Chull
    • Journal of KIISE:Databases
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    • v.29 no.6
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    • pp.453-463
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    • 2002
  • With the prevalence of multi-dimensional data such as images, content-based retrieval of data is becoming increasingly important. To handle multi-dimensional data, multi-dimensional index structures such as the R-tree, Rr-tree, TV-tree, and MVP-tree have been proposed. Numerous research results on how to effectively manipulate these structures have been presented during the last decade. Query processing strategies, which is important for reducing the processing time, is one such area of research. In this paper, we propose query processing algorithms for R-tree based structures. The novel aspect of these algorithms is that they make use of the notion of VP filtering, a concept borrowed from the MVP-tree. The filtering notion allows for delaying of computational overhead until absolutely necessary. By so doing, we attain considerable performance benefits while paying insignificant overhead during the construction of the index structure. We implemented our algorithms and carried out experiments to demonstrate the capability and usefulness of our method. Both for range query and incremental query, for all dimensional index trees, the response time using VP filtering was always shorter than without VP filtering. We quantitatively showed that VP filtering is closely related with the response time of the query.

Protective Effects of Novel Tripeptide Against Particulate Matter-induced Damage in HaCaT Keratinocytes (미세먼지에 의해 유발되는 인간각질형성세포 손상에 대한 신규 트리펩타이드의 보호 효과)

  • Lee, Eung Ji;Kang, Hana;Hwang, Bo Byeol;Lee, Young Min;Chung, Yong Ji;Kim, Eun Mi
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.47 no.1
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    • pp.75-84
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    • 2021
  • In this study, we investigated inhibitory effect of Tripeptide against particulate matter (PM)-induced damage in human keratinocytes. PM-induced cell death was inhibited by Tripeptide and the activity of aryl hydrocarbon receptor (AhR) also inhibited by Tripeptide resulting in reduced expression of its downstream targets, cytochrome P450 family 1 subfamily A member 1 (CYP1A1) and cyclooxygenase-2 (COX-2), which are responsible for toxic metabolites production and inflammation. Furthermore, PM-induced expressions of pro-inflammatory cytokines, matrix metalloproteinase-1 (MMP-1) and apoptosis-related factors were decreased by anti-oxidant activity of Tripeptide. From these results, it has been shown that the Tripeptide has protective effect against PM-induced skin damage not only through the inhibiting of keratinocyte death but also through the inhibiting the secretion of several damage-inducing factors to adjacent skin tissue. And the results suggested that Tripeptide with anti-pollution effect could be applied as a new functional cosmetic material.

Efficient Aggregate Information Management of Spatiotemporal Data in Spatial Data Warehouses (공간 데이터 웨어하우스에서 시공간 데이터의 효율적인 집계 정보 관리 기법)

  • Ryu, Ho-Sun;You, Byeong-Seob;Park, Soon-Young;Lee, Jae-Dong;Bae, Hae-Young
    • Annual Conference of KIPS
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    • 2005.05a
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    • pp.43-46
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    • 2005
  • 다차원 분석을 위한 OLAP 연산에서는 사용자의 요청에 빠르게 응답하기 위해 집계 값을 미리 계산하여 저장해 두는 사전 집계 방식을 이용한다. 시공간 데이터에 대한 사전 집계 기법으로는 R-트리의 각 노드에 대한 과거 집계 값을 요약 테이블로 관리하는 기법과 R-트리의 노드에서 현재 집계 값을 관리하는 기법이 있다. 그러나 이 기법들은 현재와 과거 모두의 집계 정보를 필요로 하는 시스템에서는 성능이 저하되며, 특히 과거 집계 정보의 경우 시간에 따른 계층화가 되어있지 않아 시간에 대한 계층 분석에 어려움이 있다. 본 논문에서는 시공간 데이터의 현재와 과거 집계 정보를 효율적으로 관리하는 기법을 제안한다. 제안 기법은 aR-tree를 이용하여 해당 영역에 대한 현재 집계 정보를 저장하고, 각 노드에 과거 집계 정보에 대한 연결을 위하여 링크를 추가하였다. 과거 집계 정보는 각 노드의 과거에서 현재까지의 집계 정보를 계층 구조로 유지하는 시간 요약 집계 테이블을 만들어 저장한다. 따라서 제안한 기법은 현재와 과거 집계 정보를 모두 유지할 수 있으므로 현재와 과거 집계 정보에 대한 처리 성능을 향상시킨다. 또한 제안 기법에서는 공간 정보를 공간 인덱스인 R-트리로 유지하고, 과거로부터의 시간 정보를 시간 요약 집계 테이블을 이용하여 계층화시켜 유지하므로 시간과 공간에 대한 계층 분석이 용이하다.

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Cutaneous hydration effect of collagen hydrolysate containing collagen tripeptides (콜라겐 트리펩타이드를 고함량으로 함유하는 콜라겐 가수분해물의 피부 보습 효과)

  • Kim, Ae-Hyang;Kim, Yi-Soo;Piao, Zhe;Shin, Yong Chul;Ha, Min Woo
    • Korean Journal of Food Science and Technology
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    • v.50 no.4
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    • pp.420-429
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    • 2018
  • Skin ageing is associated with compromised performance of its fundamental barrier functions, with undesirable changes in appearance. Since this may introduce a detrimental impact on the quality of life, significant effort to discover effective ingredients against ageing is being invested. Recently, collagen hydrolysates containing tripeptides such as GlyPro-Hyp (GPH) have been developed with anticipation of improved effects compared to that of existing collagen hydrolysate-products. To evaluate the cutaneous hydration effect of collagen tripeptides (CTP), meaningful biomarkers in human dermal fibroblasts (HDF) and NC/Nga Tnd mice were analyzed in this study. Increased levels of ceramide kinase, hyaluronic acid, collagen 1A, and hyaluronan synthase-2 (HAS2), and decreased levels of hyaluronidase-1 (HYAL1) and CD44 in HDF cells were demonstrated. Furthermore, significant reduction of transepidermal water loss (TEWL), scratching behavior, HYAL1, $TNF-{\alpha}$ and IL-6 and increased water content and HAS2 were verified by in vivo tests. These results strongly suggest the potential of CTP as a skin hydration agent.

An Efficient Index Structure for Spatial Data in Main Memory Database (주기억 데이타베이스에서 공간 데이타에 대한 효율적인 인덱스 구조)

  • 강은호;김경창
    • Proceedings of the Korean Information Science Society Conference
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    • 2003.04a
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    • pp.794-796
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    • 2003
  • 주기억 데이타베이스 시스템은 기존의 디스크 기반 데이타베이스 시스템과 달리 빠른 처리속도와 주기억 장치의 효율적인 사용이 주된 관심 사항이다. 본 논문에서는 주기억 데이타베이스에서 공간 데이터를 위한 효율적인 인덱스구조를 제시한다. 기존에 제시된 주기억 데이타베이스를 위한 인덱스 기법으로는 T-트리, Hash 계열 기법등이 제시되었으나, 이러한 모든 인덱스 기법은 1차원 데이타를 위한 인덱스 기법으로 공간 데이타에는 적용이 불가능하다. 이러한 제약을 극복하기 위해서 본 논문에서는 T-트리에 R-트리 개념을 추가 하였다.

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Aggregate Cubetree : Cubetree for Efficient Execution of Range-Aggregate Query (집계큐브리트리 :효율적인 범위-집계 질의의 수행을 위한 큐브트리)

  • 홍석진;송병호;이석호
    • Proceedings of the Korean Information Science Society Conference
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    • 2001.04b
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    • pp.163-165
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    • 2001
  • 데이터웨어하우스 환경에서는 범위-집계 질의를 효율적으로 수행하기 위해 데이터큐브로 저장뷰를 구성한다. 큐브트리란 이러한 저장뷰를 R-Tree형태로 구성하는 기법으로, 효율적인 데이터 접근성을 제공하지만 범위-집계 질의 범위 내의 모든노드를 접근해야 하는 단점이 있다. 이 논문에서는 중간노드의 MBR에 자식 노드 레코드들의 집단함수 값을 저장하여, 질의 범위에 포함되는 중간노드의 경우 단말노드를 접근하지 않고 효율적으로 범위-집계 질의를 수행할 수 있는 집계큐브트리를 제안하였다. 집계큐브트리는 기존의 큐브트리에 비해, 항상 적은 수의 노드 접근으로 질의를 수행하며 질의 범위의 크기가 커질수록 좋은 성능을 보인다.

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The Crystal and Molecular Structure of Trifluoromethyltriphenyl-1,2,4-Trioxolane (트리풀르오로메칠트리페닐-1,2,4-트리오키소란의 결정 및 분자구조)

  • 안중태;서일환
    • Korean Journal of Crystallography
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    • v.5 no.1
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    • pp.14-19
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    • 1994
  • Tlifluoromethyltriphenyl-1,2,4-tioxolane(C2IHlsF303)is triclinic, space group P1 with a=10.477(1), b= 11.056(1), c=9.917(3) A, a=104.7(1), B=122.7(1), r=63.9(1), Z=2, V=867.9(3) A3, Dc=1.43 g/cm3, λ(Mo Ka)=0.71069 A, μ=0.0116 cm-1,F(000)=384, and R=0.067 for 1713 unique observed reflections with I > 1.0 o(I). The structure was solved by direct methods and refined by fall-matrix least-squares refinement with the fixed C-H bond lengths at 0.96 A. Two phenyl rings((2) and (3)) that have the dihydral angle of 106.0°.

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