• 정보처리학회논문지:소프트웨어 및 데이터공학
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• 제2권12호
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• pp.865-872
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• 2013

Two-level 형태소 분석 방법은 규칙 기반 방법 중 하나로 형태소의 변화 현상을 규칙으로 처리하고, 기본 어휘 사전을 기반으로 형태소 결합관계를 분석한다. 이는 언어에 독립적인 방법으로 한국어에 대해서도 일부 구축되어 적용됨이 증명되었다. 그러나 기존 한국어에 대한 Two-level 형태소 분석기는 사전을 수동으로 구축하여 규모가 매우 작고 실제 사용에 제한적이었으며, 과분석이 많아 효율성이 매우 떨어졌다. 본 논문은 세종 품사부착 말뭉치에서 대규모의 Two-level 어휘 사전을 자동으로 구축하여 형태소 분석기의 적용 범위를 넓히고, 형태소간의 결합관계를 어휘 정보와 어휘 형태에 따른 하위품사 정보를 이용하여 분석함으로써 형태소 분석기의 성능을 향상시킬 수 있는 방법을 제시한다. 실험 결과, 기존의 방법보다 형태소 분석기의 과분석을 68% 이상 줄여 f-measure를 25.5% point 이상 향상시킬 수 있었다.

• 한국정보과학회 언어공학연구회:학술대회논문집(한글 및 한국어 정보처리)
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• 한국정보과학회언어공학연구회 1994년도 제6회 한글 및 한국어정보처리 학술대회
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• pp.140-145
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• 1994

형태소 분석은 단위 형태소를 분리한 후에 변형이 일어난 형태소의 원형을 복원하고, 분리된 단위 형태소들로부터 단어 형성 규칙에 맞는 연속된 형태소들을 구하는 과정이다. 이러한 일련의 분석 과정은 독립적인 특성이 강하면서 각 모듈이 서로 밀접하게 연관되어 있으므로 Two-level 모델에서는 형태론적 변형뿐만 아니라 형태소 분리 문제를 통합 규칙으로 처리하고 있다. 그러나 한국어에 Two-level 모델을 적응해 보면 형태소 분리와 형태론적 변형이 복합되어 있어서 교착어의 특성과 관계되는 단어 유형을 분석할 때 비효율적인 요소가 발견된다. 따라서 본 논문에서는 교착어인 한국어의 형태소 분석시에 발생하는 문제점들을 해결하는데 적합한 방법론으로 다층 형태론(multi-level morphology)과 다단계 모델(multi-level model)을 제안한다.

• 전자공학회논문지CI
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• 제39권6호
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• pp.11-23
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• 2002

한국어 형태론에 대한 기존의 전산모형은 선형적인 것들로 단어 내부구조 분석보다 형태소 분리 문제에만 관심을 두고 있다. 이러한 선형적 전산모형을 구문 분석 과정과 통합적으로 고려할 경우, 구문 단위 요소의 형성을 위해 형태소 분석 결과를 묶어야만 하는 추가적인 과정이 필요할 뿐만 아니라 의미적 직관성을 얻기도 어려웠다. 본 논문에서는 형태소 분리와 구문 요소 형성뿐만 아니라 단어의 구조 분석까지도 통합적으로 다룰 수 있는 단어통사론적 시각에 따른 전산 모형을 제안한다. 먼저 형태소 분리와 변형 문제를 다루기 위해 2단계형태론의 형식화를 도입하고, 품사 문맥을 반영하기 위해 기능성 구분문자를 제안한다. 그리고 형태소의 통사적 결합 검사를 위해 GLR에 기반한 변형 알고리즘을 제안한다.

• ALGAE
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• 제27권4호
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• pp.225-234
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• 2012

Zygnema is a conjugating filamentous green algal genus that is distributed in a broad range of freshwater habitats, from sea level to alpine summits. Although more than 150 species have been described worldwide, their taxonomy remains unclear, probably owing to their relatively simple morphology. We investigated the detailed morphology of Korean Zygnema species, combined with analysis of the plastid psbA gene from 22 specimens of the genus and putative relatives, in order to develope a key to their identification and isolation, and to determine their relationships. We recognized two species of Zygnema; Z. insigne and Z. leiospermum, based on morphological characters such as width of the vegetative cell, position of zygospores, dimensions and form of spores, shape of female gametangia, and color of mesospores. The analysis of psbA data was consistent with morphological comparison. The pairwise divergence between two species was 3.7-4.1% (34-38 bp) in psbA sequences. The phylogeny of psbA revealed the monophyly of Z. insigne and Z. leiospermum together with two isolates of Z. circumcarinatum from Germany and Scotland. This is the first report on the psbA gene phylogeny of Zygnema.

• 대한치과교정학회지
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• 제18권1호
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• pp.253-265
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• 1988

This study was designed to compare the normal head posture group with the extended head posture group in order to investigate the relatinship between head posture and craniofacial morphology. The subjects were devided into two groups; one included 80 children with normal head posture and occlusion, and the other 60 malocclusion patients with extended head posture. Their lateral cephalograms were traced and analysed based on 38 selected items. The following conclusion were reached. 1. The craniocervical angulations in normal group; OPT to SN, CVT to SN, OPT to FH and CVT to FH angles were $101.7^{\circ},\;104.8^{\circ},\;91.7^{\circ}\;and\;100.7^{\circ}$, respectively. 2. Compared with normal group, experimental group showed increase in mandibular plane angle, decrease in facial plane angle, airway space and posterior facial height but, there were insignificant differences in anterior facial height and tongue level between two groups. 3. Of the craniocervical angulations, OPT to FH angle was most highly correlated to the variables of the craniofacial morphology. 4. The effect of craniocervical angulation on craniofacial morphology in experimental group was different from that in comparison of normal group and experimental group.

• ALGAE
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• 제37권1호
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• pp.15-32
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• 2022

Inspecting herbaria collections of Laurencia rigida highlighted frequent misidentifications between L. rigida and L. heteroclada f. decussata, two poorly studied taxa from Australia. Recent collections of DNA material, including from topotype material, allowed for re-examination of these two taxa using molecular techniques. Detailed morphological and molecular analyses based on two markers (rbcL and COI-5P) strongly supported these two taxa as being distinct from each other and requiring nomenclatural changes. Comprehensive morphological analyses highlighted features useful for accurate identifications. Interestingly, L. rigida was found to belong to the genus Palisada with evidence from both the morphology and molecular data. Therefore, this study proposed recognizing L. rigida as Palisada rigida comb. nov. Molecular data for L. heteroclada f. decussata on the other hand supported its separation from L. heteroclada, with too great a molecular distance to be considered a variety. Morphological characters that best separated P. rigida from L. decussata included seven characters; number of pericentral cells per vegetative axial segment, the presence of secondary pit connections, the presence of lenticular thickenings, tetrasporangia alignment, the presence of corps en cerise, holdfast morphology, and overall plant shape. Morphologically, L. heteroclada f. decussata was also separated from L. heteroclada, particularly by the following characteristics; ultimate branchlets morphologies, lower order branch lengths, primary axis and holdfast morphologies. Therefore, it was proposed that L. heteroclada f. decussata is recognized at a species level as L. decussata comb. et stat. nov.

• 한국방송∙미디어공학회:학술대회논문집
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• 한국방송공학회 1996년도 학술대회
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• pp.175-180
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• 1996

In this paper, a new image segmentation method based on merging of two low contrast neighbor regions iteratively is proposed. It is suitable for very low bit rate coding. The proposed method reduces efficiently contour information and preserves subjective and objective image quality. It consists of image segmentation using 4-level hierarchical structure based on mathematical morphology and 1-level region merging structure using the contrast difference of two adjacent neighbor regions. For each segmented region of the third level, two adjacent neighbor regions having low contrast difference value in fourth level based on contrast difference value is merged iteratively. It preserves image quality and shows the noticeable reduction of the contour information, so that it can improve the bottleneck problem of segmentation-based coding at very low bit rate.

• 전자공학회논문지S
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• 제34S권7호
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• pp.78-88
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• 1997

A three dimensional-two spatical dimensions plus time-image segmentation is widely used in a very low bit rate image sequence coding because it can solve the region correspondence problem. Mathematical morphology is a very efficient tool for the segmentation because it deals well with geometric features such as size, shape, contrast and connectivity. But if the motion in the image sequence is large in time axis, the conventional 3D morphological segmentation algorithm have difficulty in solving region correspondence problem. To alleviate this problem, we propose the hierarchical image sequence segmentation algorithm that uses the region motion information. Since the motion of a region in previous level affects that in current level uses the previous motion information to increase region correspondence. Simulation result shows improved performance for sequence frames with large motion.

• 한국균학회지
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• 제52권1호
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• pp.25-33
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• 2024

Indigenous fungi from Mount Sohwangbyeongsan, Odaesan National Park, Pyeongchanggun, Gangwon-do, South Korea, were investigated between 2013 and 2016. Our survey identified a total of 137 macrofungi species. These species were systematically categorized into 2 phyla, 4 classes, 15 orders, 41 families, and 73 genera. We identified collected specimens to the species level based on their morphology and rDNA sequences. Two species-Lentinellus flabelliformis and Tricholoma stans were newly recorded as macromycota in Korea.

• 전자공학회논문지S
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• 제34S권11호
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• pp.102-113
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• 1997

In this paepr, a new image segmentation method reducing efficiently contour information causing bottleneck problem at segmentatio-based very low bit rate codingis proposed, while preserving objective and subjective quality. It consists of 4-level hierarchical image segmentation based on mathematical morphology and 1-leve region merging structure using contast of two adjacent regions. For two adjacent region pairs at the fourth level included in each region of the thid level, contrast is calculated. Among the pairs of two adjacent regions with less value than threshold, two adjacent regions having the minimum contrast are merged first. After region merging, texture of the merged region is updated. The procedure is performed recursively for all the adjacent region pairs at the fourth level included in each region of the third level. Compared with the previous method, the objective and subjective image qualities are similar. But it reduces 46.65% texture information on the average by decreasing total region number to be tansmitted. Specially, it shows reduction of the 23.95% contour information of the average. Thus, it can improve efficiently the bottleneck problem at segementation-based very low bit rate coding.