• Title/Summary/Keyword: Sequential Extraction

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An Experimental Study on Multi-Document Summarization for Question Answering (질의응답을 위한 복수문서 요약에 관한 실험적 연구)

  • Choi, Sang-Hee;Chung, Young-Mee
    • Journal of the Korean Society for information Management
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    • v.21 no.3
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    • pp.289-303
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    • 2004
  • This experimental study proposes a multi-document summarization method that produces optimal summaries in which users can find answers to their queries. In order to identify the most effective method for this purpose, the performance of the three summarization methods were compared. The investigated methods are sentence clustering, passage extraction through spreading activation, and clustering-passage extraction hybrid methods. The effectiveness of each summarizing method was evaluated by two criteria used to measure the accuracy and the redundancy of a summary. The passage extraction method using the sequential bnb search algorithm proved to be most effective in summarizing multiple documents with regard to summarization precision. This study proposes the passage extraction method as the optimal multi-document summarization method.

The Effects of pH Change in Extraction Solution on the Heavy Metals Extraction from Soil and Controversial Points for Partial Extraction in Korean Standard Method (용출액의 pH 변화가 토양내 중금속 용출에 미치는 영향과 그에 따른 국내 토양 오염 공정시험방법의 문제점)

  • 오창환;유연희;이평구;이영엽
    • Economic and Environmental Geology
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    • v.36 no.3
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    • pp.159-170
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    • 2003
  • Heavy metals are extracted from Chonju stream sediment, roadside soils and sediments along Honam expressway, soils and tailings from mining area using three different methods (partial extraction in Standard Method, partial extraction method with maintaining 0.1 N of extraction solution and Sequential Extraction Method). In samples having buffer capacity against acid, pH 1 (0.1 N HCl) of extraction solution can not be maintained and pH of extraction solution increases up to 8.0 when partial extraction in Standard Method is used. The averages and ranges of HPE(heavy metals extracted using partial extraction in Standard Method)/HPEM(heavy metals extracted using partial extraction method with maintaining 0.1 N of extraction solution) values are 0.479 and 0.145~0.929 for Cd, 0.534 and 0.078~0.928 for Zn, 0.432 and 0.041~0.992 for Mn, 0.359 and 0.011~0.874 for Cu, 0.150 and 0.018~0.530 for Cr, 0.219 and 0.003~0.853 for Pb, and 0.088 and 1.73${\times}$10$^{-5}$~0.303 for Fe. These data indicate that the difference between HPE and HPEM is large in the order of Fe, Cr, Pb, Cu, Mn, Cd and Zn. The amounts of heavy metals extracted decreases in the follow order; Sum III(sum of fraction I, II, III in sequential extraction)>HPEM>Sum III (sum of fraction I and II)>HPE for Zn, Cd and Mn and Sum III>HPEM>HPE for Cr and Fe. In the case Cr, Sum II is lower than HPEM and higher than HPE. In case of Cu, extracted heavy metals is large in the order Sum IV>HPEM>Sum III HPE. HPE/HPEM value decreases with increasing the amount of HCl used for maintaining 0.1 N of extraction solution. For samples with high buffer capacity, HPE/HPEM value in all elements is lower than 0.2. On the other hand, for samples with low buffer capacity, HPE/HPEM value are over 0.2 and many samples have values higher than 0.6 for Zn, Cd Mn and Cu due to the small difference between Sum II and Sum III, and relatively higher mobility. However, for Fe and Cr, HPE/HPEM value is below 0.2 even for samples with low buffer capacity due to their low mobility and big difference between Sum II and Sum III. This study indicates that the partial extraction method in Korean Standard Method of soil is not suitable for an assessment of soil contamination in area where buffer capacity of soil can be decreased or lost because of a long term exposure to environmental damage such as acidic rain.

Clinical Implications of the Premature Loss of the Mandibular Primary Canine (하악 유견치 조기탈락은 무엇을 의미할까?)

  • Lee, Sang-Ho
    • Journal of the korean academy of Pediatric Dentistry
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    • v.42 no.1
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    • pp.87-101
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    • 2015
  • The premature loss of the mandibular primary canine is relatively frequent and a sign of the upcoming space problems in the transitional period. This situation is caused by the permanent lateral incisor resorbing the root of the primary canine during its eruption. Bilateral loss of primary canines in a crowded arch leads to the lingual tipping of the permanent incisors, with the consequent reduction in the arch perimeter and increase in overbite. When the loss of a primary canine is unilateral, tipping of the adjacent incisors occurs toward the space, resulting in midline deviation. In these situations, treatment possibilities, such as extraction of the antimeric tooth or placement of a passive lingual arch, can be applied; although there are some controversies concerning this. Most space problems with less than 4 mm can be resolved through preservation of the leeway space using sequential disking of the primary teeth and a passive lingual arch, regaining space or limited arch expansion in the late mixed dentition. In cases with 4~6 mm of space problems, arch expansion (A-P or transverse) can be applied. Space problems with more than 6 mm should be treated through diagnosis and treatment planning. Most of these cases will require extraction of permanent teeth including serial extraction (guidance of eruption).

Eruption Guidance of Distally Displaced Mandibular Second Premolar by the Hemisection of Primary Second Molar: Two Case Reports (선행 유치의 편측치아절제술에 의한 원심으로 변위된 하악 제2소구치의 맹출 유도)

  • Yongwook, Shin;Howon, Park;Juhyun, Lee
    • Journal of the korean academy of Pediatric Dentistry
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    • v.49 no.3
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    • pp.340-347
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    • 2022
  • Distal displacement of the tooth germ of the mandibular second premolar (MnP2) leads to its impaction and obturation of the eruption path of the mandibular first molar delaying its eruption. The present case report describes the treatment of 2 cases of eruption guidance for distally displaced developing MnP2 that caused delayed eruption of the mandibular first molar. Intentional extraction of primary predecessor results in the mesial shift of the displaced MnP2. However, unfavorable distal ectopic eruption of the mandibular first premolar after the premature loss of primary second molar has been previously reported. Hemisection and sequential extraction of the mandibular primary second molar were performed to mesially shift the distally displaced MnP2, while preventing unfavorable distal ectopic eruption of the mandibular first premolar.

Evaluation of co- and Sequential Separation for Tc, Np and U by a $(TBP-TOA)/n-dodecane-HNO_3$ Extraction System ($(TBP-TOA)/n-dodecane-HNO_3$ 추출 계에 의한 Tc, Np, U의 공추출 및 순차분리 평가)

  • Lee, Eil-Hee;Lim, Jae-Kwan;Chung, Dong-Yong;Yang, Han-Beom;Kim, Kwang-Wook
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.5 no.2
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    • pp.133-143
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    • 2007
  • This study was performed to evaluate the co- and sequential separation of Tc, Np and U from the simulated multi-component HLW solution by a TBP (tributyl phosphate)-TOA (tri- octyl amine)/NDD $(n-dodecane)-HNO_3$ extraction system. An optimal condition of (30% TBP-0.5% TOA)/NDD-1 M $HNO_3$ was selected by taking account of a prevention of the 3rd phase and effects of concentration of TBP, TOA and nitric acid on the co-extraction of Tc, Np and U. In that condition, the extraction yields were 81% (Tc), 85% (Np), less than 9% (Am and RE elements), about 8% (Pd), and less than 5% (other elements) so that the system developed for the co-extraction of Tc, Np and U was proved to be available. For that, however, more than 99% of Zr was found to be pre-removed. The co-extracted Tc, Np and U were sequentially separated in order of Tc(stripping agent : 5 M $HNO_3$)${\rightarrow}Np$ by reductive stripping (reductive-stripping agent : 0.1 M AHA)${\rightarrow}U$ (stripping agent : 0.01 M $HNO_3$), and then their separation factors were evaluated. At these conditions, 95% of Tc, 98% of Np and 99% of U could be recovered in each step.

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Remediation of Soil Surrounding Abandoned Metal Mine By Using Low Molecular Weight Organic Acid (저분자 유기산을 이용한 폐금속광산 주변토양 정화)

  • 이동호;박옥현
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 1998.11a
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    • pp.183-188
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    • 1998
  • The efficiency of removing cadmium, copper, and lead from a contaminated soil of abandoned metal mine was studied in a laboratory investigation where citric acid were used to extract the metal from the soil. The contamination level of Pb, Cu in the soil A were 875.5, 667.5mg/kg respectively. The mobility and bioavailability of the metals in soil were also estimated by Sequential Chemical Extractions. Citric acid were examined for its potential extractive capabilities. Concentrations of the acid examined in this study ranged from 0.025 to 0.15M. The pH of the suspensions and S/S ratio in which the extractions were performed ranged from 2.4 to 8.1, and from 2.1:1 to 20:1. Results showed that the removal of contaminant using citric acid was pH and S/S raton dependent.

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해양 퇴적물 내 납의 흡/탈착 거동

  • 곽문용;박준형;신원식
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2004.09a
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    • pp.248-251
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    • 2004
  • 일반적으로 유기오염 물질의 경우 sequestration 또는 aging 현상에 의해 탈착저항성을 띠게 되는 것으로 알려져 있다. 그러나 중금속의 경우 흡/탈착반응은 탈착저항성이 없는 가역적 반응이라는 보고가 있는 반면 홉/탈착 반응은 비가역적이며 탈착저항성이 존재한다는 보고도 있다. 본 연구에서는 해양 연안 퇴적물에 대한 납의 흡/탈착 실험을 통하여 탈착 저항성을 화인하고 연속추출 실험을 수행함으로써 탈착 저항성 부분의 크기를 규명하고자 하였다. 그리고 각기 다른 pH(4, 6)에서 흡착 실험을 수행함으로써 pH에 따른 흡착친화도를 규명하였다. 그 결과 퇴적물에 대한 납의 흡착량은 높은 pH(6)에서 더 많았고, 각 pH 범위에서 납은 탈착저항성을 가지는 것으로 나타났으며, 연속추출결과 Organic Material bound부분에 66% 정도가 흡착되어 있음을 알 수 있었다.

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The Parallelism Extraction in Loops with Procedure Calls (프로시저 호출을 가진 루프에서 병렬성 추출)

  • 장유숙;박두순
    • Journal of Korea Multimedia Society
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    • v.4 no.3
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    • pp.270-279
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    • 2001
  • Since most program execution time is spent in the loop structure, extracting parallelism from sequential loop programs hale been focused. But, most programs hare implicit parallelism of interprocedure. This paper presents a generalized Parallelism extraction in loop\ulcorner with procedure calls. Most parallelization of loops with Procedure calls just focus on the uniform code which data dependency distance is constant. We presents algorithms which can be applied with uniform code, nonuniform code, and complex code. The proposed algorithm, loop extraction, loop embedding and procedure cloning transformation methods evaluate using CRAY-T3E. The result of performance evaluation is that proposed algorithm is an effect.

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Reverse Micellar Extraction of Fungal Glucoamylase Produced in Solid-State Fermentation Culture

  • Paraj, Aliakbar;Khanahmadi, Morteza;Karimi, Keikhosro;Taherzadeh, Mohammad J.
    • Journal of Microbiology and Biotechnology
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    • v.24 no.12
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    • pp.1690-1698
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    • 2014
  • Partial purification of glucoamylase from solid-state fermentation culture was, firstly, investigated by reverse micellar extraction (RME). To avoid back extraction problems, the glucoamylase was kept in the original aqueous phase, while the other undesired proteins/enzymes were moved to the reverse micellar organic phase. The individual and interaction effects of main factors (i.e., pH and NaCl concentration in the aqueous phase, and concentration of sodium bis-2-ethyl-hexyl-sulfosuccinate (AOT) in the organic phase) were studied using response surface methodology. The optimum conditions for the maximum recovery of the enzyme were pH 2.75, 100 mM NaCl, and 200 mM AOT. Furthermore, the optimum organic to aqueous volume ratio ($V_{org}/V_{aq}$) and appropriate number of sequential extraction stages were 2 and 3, respectively. Finally, 60% of the undesired enzymes including proteases and xylanases were removed from the aqueous phase, while 140% of glucoamylase activity was recovered in the aqueous phase and the purification factor of glucoamylase was found to be 3.0-fold.

A Study on Multiple Target Tracking Using Adaptive Neural Network and Mosaic Background Extraction (모자이크 배경이미지 추출과 적응적 신경망을 이용한 다중 보행자 추적 시스템에 관한 연구)

  • 서창진;양황규
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.7 no.8
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    • pp.1802-1808
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    • 2003
  • In this paper, we propose a method about the extraction of the pedestrian tracking trajectory in the road and we used the method of mosaic background extraction and adaptive neural network for automatic pedestrian tracking system. We used mosaic background extraction to overcome ghost phenomenon. And we detected pedestrian using differential image analysis. We used adaptive neural network for multiple pedestrian tracking that non­rigid form moving. The ART2 network is capable of detecting the mass­centers of moving objects within one frame. The history of neurons positions in the sequential frames approximates the traces of the targets. The experiments done with the network in simulated environment show promising results.