• Title/Summary/Keyword: Bottom-up method

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An Efficient Disk Block Allocation Method for XML Data (XML 데이타를 위한 효율적인 디스크 블록 할당 방법)

  • Kim, Jung-Hoon;Son, Jin-Hyun;Chung, Yon-Dohn;Kim, Myoung-Ho
    • Journal of KIISE:Databases
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    • v.34 no.5
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    • pp.465-472
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    • 2007
  • With the recent proliferation of the use of semi-structured data such as XML, it becomes more important to efficiently store and manage the semi-structured data. The XML data can be logically modelled as a rooted tree e.g., the DOM tree. In order to process a query on the XML data, we traverse the tree structure. In this paper we present an algorithm that places the XML data to disk blocks. The proposed algorithm assigns a number to each node of the tree in a bottom-up fashion. Then, the nodes are allocated to disk blocks using the assigned number. The proposed algorithm does not need access pattern information, and provides good performance for any access pattern. The characteristics of the proposed method are presented with analysis. Through experiments, we evaluate the performance of the proposed method.

A New Performance Evaluation Method for Visual Attention System (시각주의 탐색 시스템을 위한 새로운 성능 평가 기법)

  • Cheoi, Kyungjoo
    • Journal of Information Technology Services
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    • v.16 no.1
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    • pp.55-72
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    • 2017
  • Many of the studies of visual attention that are currently underway are seeking ways to make application systems that can be used in practice, and obtained good results using not only simulated images but also real-world images. However, despite that previous studies of selective visual attention are models intended to implement the human vision, few experiments verified the models with actual humans and there is no standardized data nor standardized experimental method for actual images. Therefore, in this paper, we propose a new performance evaluation techniques necessary for evaluation of visual attention systems. We developed an evaluation method for evaluating the performance of the visual attention system through comparison with the results of the human experiments on visual attention. Human experiments on visual attention is an experiments where human beings are instinctively aware of the unconscious when images are given to humans. So it can be useful for evaluating performance of the bottom-up attention system. Also we propose a new selective attention system that guides the user to effectively detect ROI regions by using spatial and temporal features adaptively selected according to the input image. We evaluated the performance of proposed visual attention system through the developed performance evaluation method, and we could confirm that the results of the visual attention system are similar to those of the human visual attention.

An Efficient Feature Point Extraction and Comparison Method through Distorted Region Correction in 360-degree Realistic Contents

  • Park, Byeong-Chan;Kim, Jin-Sung;Won, Yu-Hyeon;Kim, Young-Mo;Kim, Seok-Yoon
    • Journal of the Korea Society of Computer and Information
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    • v.24 no.1
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    • pp.93-100
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    • 2019
  • One of critical issues in dealing with 360-degree realistic contents is the performance degradation in searching and recognition process since they support up to 4K UHD quality and have all image angles including the front, back, left, right, top, and bottom parts of a screen. To solve this problem, in this paper, we propose an efficient search and comparison method for 360-degree realistic contents. The proposed method first corrects the distortion at the less distorted regions such as front, left and right parts of the image excluding severely distorted regions such as upper and lower parts, and then it extracts feature points at the corrected region and selects the representative images through sequence classification. When the query image is inputted, the search results are provided through feature points comparison. The experimental results of the proposed method shows that it can solve the problem of performance deterioration when 360-degree realistic contents are recognized comparing with traditional 2D contents.

Experimental Studies of the Short-Term Fluctuations of Net Photosynthesis Rate of Norway Spruce Needles under Field Conditions (야외조건하(野外條件下)에서 독일가문비(Picea abies Karst) 침엽(針葉)의 순(純) 광합성률(光合成率)의 단기(短期) 변화(變化)에 대한 실험적(實驗的) 연구(硏究))

  • Bolondinsky, V.;Oltchev, A.;Jin, Hyun O.;Joo, Yeong Teuk;Chung, Dong Jun
    • Journal of Korean Society of Forest Science
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    • v.88 no.1
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    • pp.38-46
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    • 1999
  • Canopy structure conductances of a Norway spruce forest in the Solling Hills(Central Germany) and Central Forest Biosphere Reserve(320km to the north-west from Moscow) were derived from LE(latent heat flux) and H(sensible heat flux) fluxes measured(by Eddy correlation technique and energy balance method) and modelled(by one dimensional non-steady-state) SVAT(soil-vegetation-atmosphere-transfer) model(SLODSVAT) using a rearranged Penman-Monteith equation("Big-leaf" approximation) during June 1996. They were compared with canopy stomatal conductances estimated by consecutive intergrating the stomatal conductance of individual needles over the whole canopy("bottom-up" approach) using SLODSVAT model. The result indicate a significant difference between the canopy surface conductances derived from measured and modelled fluxes("top-down" approach) and the stomatal conductances modelled by the SLODSVAT("bottom-up" approach). This difference was influenced by some nonphysiological factors within the forest canopy(e.g. aerodynamic and boundary layer resistances, radiation budget, evapotranspiration from the forest understorey). In general, canopy surface conductances derived from measured and modelled fluxes exceeded canopy stomatal conductance during the whole modelled period, The contribution of the understorey's evapotranspiration to the total forest evapotranspiration was small (up to 5-9% of the total LE flux) and was not depended on total radiation balance of forest canopy. Ignoring contribution of the understorey's evapotranspiration resulted in an overestimation of the canopy surface conductance for a spruce forest up to 2mm/s(about 10-15%).

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Studies on the Eurytrema pancreaticum (췌질(膵蛭)에 관한 연구(硏究) [III] 충란검사법(蟲卵檢査法)의 개량(改良))

  • Jang, Du Hwan
    • Korean Journal of Veterinary Research
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    • v.10 no.1
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    • pp.25-31
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    • 1970
  • The techniques which have been used for the fecal examination of ruminant infected with the pancreatic flukes, Eurytrema Pancreaticum, were reviewer in their efficiency to detect the ova. One of modified fecal examination: H.F.E. (hydrochloric acid-formalin-ether) sedimentation method was devised in this study. Efficiency in the detecting ability of the fluke eggs with H.F.E. sedimentation method was determined by a series of repeat tests. Among 20 head of cattle known to harbor 1-5 adult worms of the pancreatic fluke, 75% of the infected cattle were detected, and among 60 head of cattle known to harbor more than 6 adult worms, 95% of the infected cattle were detected with H.F.E. sedimentation method. The procedures of the H.F.E. sedimentation method are as follows; 1) Take the sample 5-10 gm., emulsify throughly with 20 ml. of 50% hydrochloric acid in a cup. 2) Strain this mixture through one or two layers of wet surgical gauze into 15ml. centrifuge tube. 3) Washing the cup with 5ml. of 50% hydrochloric acid and strain again. 4) Centrifuge at 2,300 rpm. for 2 minutes. 5) Pour off the supernatant fluid. 6) After the sediment mixed with 10% formalin, stand for 5 minutes. 7) Add 2-3ml. of ether, shake vigorously up and down, after the top of the tube covered with thumb. 8) Centrifuge at 2,300 rpm. for 2 minutes. 9) Loosen the fecal plug in the tube by ringing with an applicator stick. 10) Quickly, but carefully, pour of all, but the bottom layer of sediment. 11) Thoroughly mix the sediment, pour on a slide (or pick up it with a pipett), mount with a cover glass. 12) Examine carefully.

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An Experimental Study on the Stress Behavior of Coped Stringers in Steel Railway Bridge - II : Repair · Strengthening Method (철도교 세로보 절취부에서의 응력거동에 관한 실험적 연구 - II : 보수·보강 방법)

  • Li, Guang Ri;Park, Young Suk
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.29 no.4A
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    • pp.307-313
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    • 2009
  • In this study, in order to research the repair-strengthening methods, when fatigue crack occurs in the coped stringers of a steel railway bridge, we manufacture the full size of crossbeam-stringer and floor system model. Also the experimental test is performed on the coped stringers applying the repair-strengthening methods using the stop hole, combination plate, connection plate, bracket, and so on. The results indicate that, the most effective method is to set up connection plate and bracket in the top flange and bottom flange of the stringers, while we can consider the method of punching stop holes in the end of the crack as a subsidiary method. It is necessary to set up the combination plate when the length of crack is quite long.

A Study on the Slacks pattern for Pregnant Women - focused on slacks pattern for mid or second half period of puegency - (임산부용 슬랙스 패턴설계에 관한 연구 - 임신중기.말기의 기본 슬랙스 패턴설계를 중심으로 -)

  • Na, Mi-Hyang;Kim, Youen-Hee;Kim, Mi-Sun
    • Korean Journal of Human Ecology
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    • v.9 no.4
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    • pp.471-482
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    • 2000
  • The purpose of this study is to produce slacks pattern for pregnant women in the mid or second half period of their pregnancy according to the development figure of the body shell from a follow-up measurement. We here would like to produce slacks pattern for pregnant women constructed to fit better with their individual property in their figure and to help maintain the shape and beauty of the lower half of body and would compare it with two manufactured slacks pattern. The results of the study were as follows; 1. As the pregnancy proceeds, the height of natural-waist line went up spontaneously due to the projection of abdominal region, therefore, it was given darts at the front zipper part so that they could maintain a nice figure and to avoid possibility of feeling oppressed. To acquire a slimmer outfit, we made of the slacks-bottom narrower than the width at the knee line, and it worked out. 2. Sensory evaluation for appearance: According to the statistical of the result of 19items on the questionaire, all items showed significant difference(a$\leq$0.01) between the new and A(bunka) B(Kim's pattern) method slacks pattern, with the new pattern having higher scores. The new drafting method proved to be better fitted, to fit the shape of bodies properly and to get a visual effect to look slim.

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A Fundamental Study on Nano-cement by Chemical Synthesis (화학적 방법에 의한 나노시멘트 개발에 관한 기초 연구)

  • Jo, Byung-Wan;Kang, Seok-Won;Yoon, Kwang-Won;Choi, Ji-Sun
    • Journal of the Korea Concrete Institute
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    • v.21 no.6
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    • pp.713-718
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    • 2009
  • Advanced industries-IT, BT, NT and ET are rapidly developing in 21 century. And the cement industry is becoming the principal factor in air pollution because of the creation of $CO_2$ during manufacturing. Also, the cement industry will be faced with a crisis due to the exhaustion of natural resources. In this study, nano cement by Bottom-up method of a chemical synthesis was developed. The generation of $CO_2$ during the plasticization process of cement manufacturing was avoided. The purpose was to produce building materials that have both high strength and durability as the high value-added growth engine industry of the 21 century. The nano cement was developed using hydrothermal synthesis. This is a method of mixing after ripening, by manufacturing the high density gel and low gel, which does not require special test equipment or pressure conditions to produce. Particle size, SEM, EDX, and porosity tests were conducted. This study investigated the compressive strength of concrete with various compositions. Specimens were tested for compressive strength at 3, 7, 14 and 28 days. The medium-sized (50% by weight) cement particles created by chemical synthesis were less than 168 nm. The compressive strength of the mortar prepared using this cement was 53.9 MPa. But it was judged that succeeding study will be necessary for development of nano building materials with high ability and economical analysis.

An Efficient Sequence Matching Method for XML Query Processing (XML 질의 처리를 위한 효율적인 시퀀스 매칭 기법)

  • Seo, Dong-Min;Song, Seok-Il;Yoo, Jae-Soo
    • Journal of KIISE:Databases
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    • v.35 no.4
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    • pp.356-367
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    • 2008
  • As XML is gaining unqualified success in being adopted as a universal data representation and exchange format, particularly in the World Wide Web, the problem of querying XML documents poses interesting challenges to database researcher. Several structural XML query processing methods, including XISS and XR-tree, for past years, have been proposed for fast query processing. However, structural XML query processing has the problem of requiring expensive Join cost for twig path query Recently, sequence matching based XML query processing methods, including ViST and PRIX, have been proposed to solve the problem of structural XML query processing methods. Through sequence matching based XML query processing methods match structured queries against structured data as a whole without breaking down the queries into sub queries of paths or nodes and relying on join operations to combine their results. However, determining the structural relationship of ViST is incorrect because its numbering scheme is not optimized. And PRIX requires many processing time for matching LPS and NPS about XML data trees and queries. Therefore, in this paper, we propose efficient sequence matching method u sing the bottom-up query processing for efficient XML query processing. Also, to verify the superiority of our index structure, we compare our sequence matching method with ViST and PRIX in terms of query processing with linear path or twig path including wild-card('*' and '//').

A Comparative Study for Estimation of Greenhouse Gas for Local Government`s Sustainable Transport (지속가능교통 평가를 위한 온실가스 배출량 산정 방법론의 지자체 적용 및 비교 연구)

  • Yu, Byeong-Yong;Bae, Sang-Hun;Han, Sang-Yong;Kim, Geon-Yeong
    • Journal of Korean Society of Transportation
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    • v.29 no.5
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    • pp.55-65
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    • 2011
  • In effort to estimate sustainability of the transportation sector, this study conducts a comparative analysis of methodology suggested for measuring greenhouse gas emission. There are two approaches proposed by the UN IPCC: 1) top-down approach (TDA) based on the amount oil sales, and 2) bottom-up approach (BUA) utilizing the velocity of moving source and traffic volume data. The subject areas for analysis were selected based on research results by the Korea Transportation Institute that evaluate traffic sustainability of each local government. Gwacheon-si being one of the top ranked areas in sustainability, and Anseong-si being ranked at the 7th level were analyzed. By the tier 1 methodology, Gwacheon-si and Anseong-si are estimated to create 74,813ton/yr, and 584,125ton/yr of the greenhouse gas emission, respectively. The tier 3 methodology, however, estimates Gwacheon-si and Anseong-si to create 91,462ton/yr, and 163,801ton/yr of the emission, respectively. Comparison of the two estimated emissions shows considerable differences; i.e., the tier 3 method over estimates Gwacheon-si's emission by 22.3% whereas it underestimates Anseong-si's greenhouse gas emission by the factor of about 3.5 compared to the emissions obtained from the tier 1 method. The result from this study implies that the traffic-sustainability-index based grade of each local government can be evaluated differently by the method adopted for measuring greenhouse gas emission.