문단 단위 가중치 함수와 문단 타입을 이용한 문서 범주화

주원균,김진숙,최기석,Joo, Won-Kyun,Kim, Jin-Suk,Choi, Ki-Seok 한국정보처리학회 2005 정보처리학회논문지B Vol.12 No.6

문서 범주화 분야에 대한 연구들은 전체 문서 단위에 한정되어 왔으나, 오늘날 대부분의 전문들이 주요 주제를을 표현하기 위해서 조직화 된 특정 구조로 기술되고 있어, 텍스트 범주화에 대한 새로운 인식이 필요하게 되었다. 이러한 구조는 부주제(Sub-topic)의 텍스트 블록이나 문단(Passage) 단위의 나열로서 표현되는데, 이러한 구조 문서에 대한 부주제 구조를 반영하기 위해서 문단 단위(Passage-based) 문서 범주화 모델을 제안한다. 제안한 모델에서는 문서를 문단들로 분리하여 각각의 문단에 범주(Category)를 할당하고, 각 문단의 범주를 전체 문서의 범주로 병합하는 방법을 사용한다. 전형적인 문서 범주화와 비교할 때, 두 가지 부가적인 절차가 필요한데, 문단 분리와 문단 병합이 그것이다. 로이터(Reuter)의 4가지 하위 집합과 수십에서 수백 KB에 이르는 전문 테스트 컬렉션(KISTl-Theses)을 이용하여 실험하였는데, 다양한 문단 타입들의 효과와 범주 병합 과정에서의 문단 위치의 중요성에 초점을 맞추었다 실험한 결과 산술적(Window) 문단이 모든 테스트 컬렉션에 대해서 가장 좋은 성능을 보였다. 또한 문단은 문서 안의 위치에 따라 주요 주제에 기여하는 바가 다른 것으로 나타났다. Researches in text categorization have been confined to whole-document-level classification, probably due to lacks of full-text test collections. However, full-length documents availably today in large quantities pose renewed interests in text classification. A document is usually written in an organized structure to present its main topic(s). This structure can be expressed as a sequence of sub-topic text blocks, or passages. In order to reflect the sub-topic structure of a document, we propose a new passage-level or passage-based text categorization model, which segments a test document into several Passages, assigns categories to each passage, and merges passage categories to document categories. Compared with traditional document-level categorization, two additional steps, passage splitting and category merging, are required in this model. By using four subsets of Routers text categorization test collection and a full-text test collection of which documents are varying from tens of kilobytes to hundreds, we evaluated the proposed model, especially the effectiveness of various passage types and the importance of passage location in category merging. Our results show simple windows are best for all test collections tested in these experiments. We also found that passages have different degrees of contribution to main topic(s), depending on their location in the test document.

메타데이터 기반의 연구성과정보 검색시스템의 개념적 설계

박동진,이상태,최기석,Park, Dong-Jin,Lee, Sang-Tae,Choi, Ki-Suk 한국과학기술정보연구원 과학기술정보센터 2006 Journal of Information Science Theory and Practice Vol.37 No.2

최근 연구성과정보의 원활한 교환 및 유통은 연구생산성 향상에 가장 핵심적인 요인으로 인식되고 있다. 그래서 국가적으로 그리고 각 연구기관에서는 연구성과정보 서비스를 위한 시스템을 계획하거나 구축 중에 있다. 그러나 연구정보들은 서로 다른 형태로 분산되어 있으며, 연구정보를 기술하는 방식에 있어서도 기관별 그리고 연구자 개인별로 많은 차이가 있어서 연구성과정보의 통합에 있어서 많은 제약이 있다. 따라서 본 연구는 시맨틱 웹 기술을 도입하여 연구성과정보의 메타데이터에 대한 상호운용성을 제고하는 방안을 제시함으로써 궁극적으로 연구성과정보의 통합을 지원하고자 한다. 특히 과학기술정보표준화위원회에서 제시한 연구성과정보 메타데이터 표준(안)을 기초로 개발되는 온톨로지는 용어들에 대한 구조적인 그리고 의미적인 통합을 가능하게 하며, RDF/RDFS를 이용한 메타데이터 지식표현은 정보 서비스의 검색과 유통에 있어서 지능적인 서비스를 가능하게 한다. 또한 본 연구를 통하여 제시한 시스템의 개념적 구조는 시맨틱 웹 기반의 검색시스템 개발에 있어서 주요 기능, 구성요소, 적용기술 및 상세 설계의 방향을 제시한다. 본 연구에서 제안한 메타데이터를 통한 시스템의 통합방식은 기존의 연구성과정보 시스템의 서비스 영역을 확대할 뿐 아니라, 더욱 정교해진 지능적인 검색 서비스도 가능하게 한다. It has lately been recognized that the sharing and exchanging of the research results information is the critical factor to improve the research productivity. So many institutions are planning or developing the information systems which provide the research information services for researcher. But it has very difficulty in integrating the research resources information due to the dispersion and heterogeneity in data sources, and semantic and structural difference in describing data. We propose the semantic web based methodology and conceptual framework for raising the interoperability of metadata about research results information, which will support the integration of the distributed research data for information services in the end. We first introduce the ontology which is developed based on Standard Metadata of Research Results Information published by STISC. Then to show the applicability in real-world environment, we express the metadata of research information in RDF/RDFS according to ontology. Finally we proposed the conceptual architecture of research information service system which shows the main components, the functional requirements, and the principal and design direction at implementing the system.

GIS내 금속이물의 전계해석

조국희(Kook Hee Cho),이강수(Kang Su Lee),고영주(Young Ju Ko),최기석(Ki Suk Choi),박하용(Ha Young Park),박중신(Joung Shin Park),곽희로(Hee Ro Kwak) 대한전기학회 1998 대한전기학회 학술대회 논문집 Vol.1998 No.7

뇌동맥류성 지주막하출혈 환자의 적혈구 용적, 혈액 점도 및 혈장 점도

최기석,임만빈,손은익,김동원,김인홍,전동석 대한신경외과학회 1990 Journal of Korean neurosurgical society Vol.19 No.4

In order to find out the relationship between blood viscosity and the development of an ischemic symptom(clinical vasospasm) following an aneurysmal subarachnoid hemorrhage (SAH), we checked daily the hematocrit(Hct), blood viscosity and plasma viscosity from admission day to 14 days after a SAH in 33 patients. Twelve patients with diseases except those with a SAH were selected as a control group. We analyzed the difference of the average hematocrit, blood viscosity, and plasma viscosity between the control group, non-spasm group and spasm group on admission, and then the period of preoperative, postoperative with mannitolization, and postoperative without mannitolization. We also analyzed the change of those according to the SAH day, and the relationship between the blood viscosity and the level of hematocrit in each group. As a result, aneurysmal SAH patients with clinical vasospasm showed a higher plasma viscosity than the control(1.82±0.21 vs. 1.55±0.14, respectively : p<0.01) and clinical non-spasm(1.82±0.21 vs. 1.66±0.12, respectively : p<0.05) group of patients on admission statistically. In the spasm group, the blood viscosity was raised during the spasm risk period (SAH 7-10 days). The level of the hematocrit in the spasm group was lower than the non-spasm group and most of them checked below 30% after surgery. In the relationship between the level of hematocrit and the blood viscosity, the spasm group showed a relatively higher blood viscosity than the non-spasm group. These results suggest that the blood viscosity has some role in the development of ischemic symptoms after a subarachnoid hemorrhage, but major determinants such as erythrocyte aggregation, plasma fibrinogen concentration and platelet aggregation which affect the microcirculation have a more important role. Therefore, when hemodilution are used for prevention or improvement of ischemic symptoms after subarachnoid hemorrhage, the level of the hematocrit and the focus on decreasing the major determinants of the viscosity in microcirculation should be considered.

자발성 및 외상성 지연성 뇌척수액 비루의 수술적 치료

최기석,김상열,임만빈,손은익,김동원,김인홍 대한신경외과학회 1989 Journal of Korean neurosurgical society Vol.18 No.7-12

The authors presented 9 cases of surgically treated CSF rhinorrhea, two of which were spontaneous and 7 were traumatic delayed. The duration of leakage was longer than 1 month in most cases and seven of the nine cases were complicated by meningitis. The leakage site was most accurately detected by metrizamide computed tomographic cisternography(MCTC) and the most frequent leakage site was the cribriform plate. Good surgical results were obtained by direct repair and/or shunt without recurrence during follow-up period from 7 months to 2 years.

뇌수막종의 임상적 고찰

최기석,김동원,손은익,임만빈,김인홍 啓明大學校 醫科大學 1989 계명의대학술지 Vol.8 No.2

In order to predict the possibility of compplete resection of intracranial meningioma according to anaatomical sites, the authors have analyzed 36 surgical cases of intracranial meningiomas retrospectively from June, 1982 to May, 1988. The distribution of the sites in the intracranial meningiomas were; convexity (27.8%), paarasagittal and falx(25%), middle cranial fossa(22.2%), anterior cranial fossa(13.9%), posterior cranial fossa(5.6%). intraventricular(5.6%) area. Convexity and intraventricular meningiomas were removed totally in all of 12 cases and parasagittal and falx meningiomas were removed totally in 8 cases and subtotally in 1 case. Anterior fossa were removed totally in 3 cases, subtotally in 1 cases and partially in 1 case. Middle fossa were removed totally in 5cases, subtotally in 2 cases and partially in 1 cases. Posterior fossa were removed totally in 1 case and partially in 1 case. Therefore miningiomas that removed totally and subtotally were 33 cases(91.6%) and partially in 3 cases (8.4%). The outcome at discharge was excellent in 20 cases(55.6%), good in 10 cases (27.8%), faair group in 4 cases(11.1%). The mortality rate was 5.6%(2 cases). From this study, we concluded that intracranial meningiomas could remove totally, which were located in convexity, parasagittal and falx, orbit, olfactory groove, lateral sphenoidal ridge, pyramid, intraventricle and posterior convexity, but wwere difficult to total removal in medial sphenoidal ridge, cavernous sinus and faloctentorial junction.

경추 외상 환자 치료에 대한 임상적 고찰

김인수,김동원,최기석,박병규,이장철,임만빈,김인홍 대한신경외과학회 1992 Journal of Korean neurosurgical society Vol.21 No.5

A retrospective study of 100 cervical spinal cord injury patients adimtted consequtively to the Department of Neurosurgery, Dongsan Medical Center, Keimyung University between March, 1985 and June, 1989 was conducted. The average age was 42 and 84(84%) were male. The majority sustained their spinal cord injury in a motor vehicle accident(50%) or in a diving accident(36%). Thirty-three percent(33/100) of these patients had surgical intervention by anterior approach (14/33), posterior approach(17/33) and total laminectomy(2/33). The others were only immobilized by traction or neck brace. Not only neurological recovery in operated and nonoperated patients but also complete and incomplete injury was compared. The degree of the neurological injury was classified by the Frankel classification. 12 cases turned out to be more aggravated than the condition at admission, among them 9 cases were middle and low cervical incomplete injuries. At final follow-up no appreciable differences in achievement in activities of daily living and mobility were noted between patients treated with surgical stabilization of the cervical spinal column and those treated nonsurgically.