한국인 성인의 상악 전치부 치조골 형태에 관한 방사선학적 연구

서효석,정진형,임성빈,홍기석,Seo, Hyo-Seok,Chung, Chin-Hyung,Lim, Sung-Bin,Hong, Ki-Seok 대한치주과학회 2006 Journal of Periodontal & Implant Science Vol.36 No.2

In order to achieve a satisfactory esthetic result of periodontal surgery or implant in maxillary anterior area, periodontists must be aware of normal alveolar bone anatomy. The purpose of this study was to evaluate the relationship of alveolar bone morphology to tooth shape and form. 78(mean age : 25 yrs) periodontally healthy volunteers participated in this study. Two maxillary central incisor and one lateral incisor were selected to study. With minimal local anesthesia, gutta-percha cone inserted to labial gingival sulcus of selected teeth just after bone sounding with periodontal probe. Metal ball (4mm diameter) attached to palatal fossa of central incisor. Then, periapical radiograph was taken according to long cone paralleling technique. After film scan, labial alveolar bone profile reproduced along interproximal bone and apical ends of gutta-percha cones on computer screen. By utilizing computer program, the distance from height of interproximal bone to the labial bone crest in central incisor-central incisor and central incisor-lateral incisor area was measured and converted to real distance by using vertical length of metal ball on film. After measuring crown length & width of central incisor, the 10 individuals ranked lowest GW/L ratio (crown width/length ratio) and the 10 ranked highest were selected as having a long-narrow(group N), or a short-wide(group W) form of the central incisors. Means of the distance from height of interproximal bone to the labial bone crest of group N, W were calculated and compared by means of independent t-test. The results were as follows: 1. Mean distance from the height of the interproximal bone to the labial bone crest was $3.5{\pm}0.7mm$ between two central incisor, and $2.8{\pm}0.6mm$ between central and lateral incisor. 2. Mean GW/L ratio of group N was 0.57, and group W was 0.8. Mean distance from the height of the interproximal bone to the labial bone crest of group N was higher than group W in both measured area(measurements of group N, W were $3.9{\pm0.2mm$ and $3.5{\pm}0.2mm$ between two central incisor, $3.0{\pm}0.2mm$ and $2.8{\pm}0.2mm$ between central and lateral incisor), but there were no statistically significant differences when the groups were compared. Within the limits of the present study, there was a tendency that subjects with long-narrow teeth have more scalloped alveolar bone profile than subjects with short-wide teeth in upper anterior area, but no statistically significant differences were found.

C-G 링커 어댑터 PCR을 이용한 지놈워킹

서효석,이영기,전은영,이정헌,Seo, Hyo-seok,Lee, Yung-gi,Jeon, Eun-young,Lee, Jeong-heon 한국연초학회 2015 한국연초학회지 Vol.37 No.1

Genome walking is a par ticular application for identifying sequences of unknown genomic regions adjacent to a known region. Many genome walking methods based on polymerase chain reaction (PCR) are available. Even if earlier techniques suffer from low reproducibility, inefficiency, and non-specificity, improved strategies have been developed. In this study, we present an alternative strategy: the genomic DNA is digested with restriction enzymes. After cytosine overhangs at 5' ends, the fragments are ligated to linker adaptor s had guanine overhang at 3' ends. Then nested PCR is performed. The improvements in this strategy focus on two points. The first is the C tailing method using Pfu polymerase instead of the A tailing method based on nontemplate-dependent terminal transferase activity of Taq polymerase. Therefore unintended modification of target DNA can be prevented without A tailing error. The second point is the use of C/G-specific ligation had advantage in the ligation efficiency compared with A/T-specific ligation. Therefore, the C-G linker PCR method increases ligation efficiency between digested genomic DNA and adaptor DNA. As a result, the quantity of target DNA to amplify by PCR is enriched. We successfully used G-C linker PCR to retrieve flanking regions bordering the phophinothricin resistance gene in genetically modified tobacco (GMO).

모바일 환경에서 사용자 행동 추론에 기반을 둔 개인화 추천 서비스

서효석(Hyo-Seok Seo),권일경,이상용(Sang-Yong Lee) 한국지능시스템학회 2011 한국지능시스템학회 학술발표 논문집 Vol.21 No.2

경혈에 적용한 은침점 자극치료가 두통환자의 중대뇌동맥 혈류속도 및 통증에 미치는 영향

서효석 ( Hyo Seok Seo ),윤영대 ( Young Dae Yun ) 대한경락경혈학회 2008 Korean Journal of Acupuncture Vol.25 No.3

Objectives: The aim of this study is to examine the effects of SSP(silver-spike point) therapy, applied to acupuncture points, on the middle cerebral arteries blood flows of sample group(tention-type headache patients, n=12) and control group(non tension-type headache patients, n=12), and on the reduction of their headaches, when applied to acupuncture points. Methods: We stimulated 6 acupuncture points for headache with the SSP(three times a week for three weeks), and measured VAS(visual analogue scale) and the blood flow of the middle cerebral arteries with TCD(transcranial doppler ultrasonography). Results: The blood flow of the middle cerebral artery and VAS of the sample group and the control group were compared four times(initial, 1weeks, 2weeks, 3weeks) and significant differences in the measurements were found at 3 weeks(p<.05). The blood flow of the middle cerebral artery of the sample group was significantly increased, and VAS was significantly decreased in both groups. Conclusions: The silver-spike-point Low-frequency electrical-stimulation treatment, applied to acupuncture points, can significantly increase the blood flow of the middle cerebral arteries in headache patients and can thus alleviate their headaches.

가중치를 적용한 정형적 개념분석을 통한 속성, 객체, 개념의 중요도 산출 기법

서효석(Hyo-Seok Seo),윤성민(Sungmin Yoon),이희정(Heejung Lee) 대한산업공학회 2020 대한산업공학회지 Vol.46 No.6

두경부에서 발생한 융기성 피부섬유육종 치험 6례

서효석(Hyo Seok Seo),서상원(Sang Won Seo),장충현(Choong Hyun Chang),강민구(Min Gu Kang),장 학(Hak Chang) 대한두경부종양학회 2008 대한두경부 종양학회지 Vol.24 No.2

Objectives :DFSP(Dermatofibrosarcoma protuberans) is an uncommon, slowly growing, locally invasive malignant tumor that usually presents as a painless, often long-standing mass arising in the dermis of skin. It occurs most frequently on the trunk and proximal parts of the limbs, less commonly in the head and neck region and has a frequent tendency to recur after surgical excision. Clinically, the initial appearance of the tumor similar to that of benign tumor such as keloid and dermatofibroma. Therefore, accurate clinical diagnosis and adequate surgical excision are important. Materials and Methods :We experienced 6 patients of DFSP in head and neck during the recent 6 years, 5 male and 1 female patients. The age of the patients ranged from 31 to 66. As reconstructive methods, the authors used cervicofacial flap, trapezius musculocutaneous flap, TRAM flap, anterolateral thigh free flap and skin graft. Results :The patients were followed up after operation from 24 to 79 months and all remained free of disease except one case, who occurred at forehead area. Conclusion :We present the experience of 6 cases of DFSP occurred in head and neck. We obtained satis-factory results with appropriate diagnosis and treatment which wide excision with surgical margins 3-5cm. We also present an operative plan of this locally aggressive and highly recurrent tumor.

미로 탐색 알고리즘 테스트를 위한 플랫폼 개발

서효석(Hyo-Seok Seo),박재민(Jae-Min Park),이상용(Sang-Yong Lee) 한국지능시스템학회 2010 한국지능시스템학회논문지 Vol.20 No.1

마이크로 마우스를 이용한 다수의 미로 경진대회가 개최되어 미로 탐색 알고리즘의 성능이 비교되고 있으며, 미로 탐색 알고리즘은 좌(우)수법, 구심법, 언덕오르기 등을 기본으로 하여 다양한 형태로 적용되어 사용되고 있다. 하지만 미로 탐색 알고리즘을 적용하여 테스트하기 위한 소프트웨어 플랫폼이 없어서 프로그램을 직접 개발하거나 하드웨어를 통해 알고리즘의 성능을 테스트해야 하는 불편함을 겪는다. 본 연구에서는 하드웨어로 구현이 어려운 다양한 형태의 미로 제작과 알고리즘의 손쉬운 적용이 가능하고, 스텝, 연산 횟수, 탐색 시간의 평가가 가능한 미로 탐색 알고리즘을 위한 플랫폼을 개발하였다. 플랫폼은 메인 레이어, 인터페이스 레이어, 사용자 레이어의 분리 구조로 되어 알고리즘을 쉽게 교체적용 할 수 있는 장점이 있다. 플랫폼의 실험을 통하여 미로 탐색 알고리즘들의 성능을 평가하고 분석하여 알고리즘의 개발 및 실험에도 적용할 수 있음을 확인하였다. Many contests by micro mouse was celebrated of which maze search algorithms performance are compared. That is used in various forms based on left(right) weight method, euclidean algorithm method, hill climbing method. However we feel uncomfortable to test algorithms performance through direct development of programs or hardwares as no software platform to test in maze search algorithms. In this research we develop of a platform for maze search algorithms that is easily to produce various forms of maze that are hard to be realized by hardware, to apply algorithms, and evaluate the seek time, operation count, steps and performance. The platform is consist of main layer, interface layer, user layer which has merit to apply and replace easily algorithms. We verified that the maze search algorithm can be applied even in the development and experiment of algorithm by evaluating and analyzing its performance through the experiment of platform.

혼합현실 기반의 가상 세계 온라인 강의 시스템

권오영 ( Oh Young Kwon ),서효석 ( Hyo Seok Seo ),구스타보텔레스 ( Gustavo Teles ) 한국실천공학교육학회 2011 실천공학교육논문지 Vol.3 No.1

가상 환경에서의 학습 시스템은 기존 E-Learning 시스템에서 부족했던 몰입감을 주고 사용자의 흥미 유발을 촉진할 수 있고 위험하거나 비용이 많이 드는 교육 컨텐츠를 제공할 수 있다. 본 논문에서 학습 유형을 실시간강의, 상시 학습, 실습 교육, 그리고 스터디 그룹 활동으로 구분하였다. 혼합 현실을 제공하는 가상 세계인 Second Life를 이용하여 이들 학습 유형을 지원하는 온라인 강의 시스템을 구축하였다. 구축된 온라인 강의 시스템을 운영함으로써 가상 학습 환경을 제공하였다. Learning system on virtual environment gives the immersive feeling that lacks in existing E-Learning system, excites user`s interest, and offers dangerous and expensive education contents. In this paper, we classified the learning categories into four classes: realtime lecture, anytime study, practice education, and the activity of study group. We built the on-line lecture system using Second Life that supports 3D virtual world and mixed reality. We provided virtual learning environment as running developed virtual world on-line lecture system.

동질성 및 열노화 분석을 통한 방호도장의 건전성 평가

조남진(Cho Nam jin),임동수(Im Dong su),윤홍걸(Yoon Hong gul),서효석(Seo Hyo seok),윤기열(Yun Ki youl) 한국방재학회 2017 한국방재학회논문집 Vol.17 No.2

원자력발전소 격납건물 내부에는 부식방지, 제염, 내화기능 등의 목적으로 방호도장이 시공되어 있다. 격납건물 내부도장에 결함이 있을 경우, 지진, 화재 등에 의한 설계기준사고(Design Basis Accident) 발생 시 격납건물 살수계통의 작동으로 분사되는 고압의 분무수로 인해 도장이 벗겨질 가능성이 크다. 이로 인한 재순환냉각계통의 기능상실로 대규모 사고를 가져 올 수 있다. 격납건물 내부 방호도장의 상태점검을 해본 결과 일부에서 다양한 형태의 결함들이 발견되었다. 이렇게 발견된 결함들의 원인을 분석하고, 방호도장의 건전성을 평가하기 위해 기존 도장재와의 동질성 분석 및 열노화상태 평가를 수행하였다. 시험결과를 통해 가동중 원전에 적용되고 있는 도장은 전반적으로 건전성을 유지하는 것으로 평가되기는 하였으나, 향후 관련 기술 및 평가방법론에 대한 추가적인 연구가 필요할 것으로 판단된다. Inside the containment buildings of Nuclear Power Plant, protection coatings are installed to prevent corrosion, decontamination, and fireproof. If there is a defect in the coating, there is a high possibility that the coating will be peeled off due to the operation of the containment building Spray system when a design basis accident occurs due to an earthquake or fire. This can lead to massive damage due to the loss of functionality of the recirculation cooling system. various defects are found in the protective coatings inside the containment buildings. In order to analyze the causes of these defects and evaluate the integrity of the protective coating, we analyzed the homogeneity with the existing paint and evaluated the thermal aging condition. Through the test results, the state of the painting was evaluated to maintain overall soundness, however, further research on related technologies and evaluation methodologies will be needed in the future.

k-means 클러스터링과 시계열 분석을 이용한 컨텍스트 예측 기반 개인화 서비스

최영환(Young-Hwan Choi),권일경(Il-Kyoung Kwon),김진태(Jin-Tae Kim),서효석(Hyo-Seok Seo),이상용(Sang-Yong Lee) 한국지능시스템학회 2010 한국지능시스템학회 학술발표 논문집 Vol.20 No.1

사용자 컨텍스트의 예측은 유비쿼터스 환경에서 사용자의 성향을 분석하여 개인화된 서비스를 제공하기 위해 사용된다. 본 논문에서는 k-means 클러스터링과 시계열 분석을 이용하여 사용자의 컨텍스트를 예측하고 이를 기반으로 개인화 서비스를 제공하는 시스템을 제안한다. 사용자 컨텍스트의 예측을 위해 k-means 클러스터링으로 비슷한 성향을 보이는 사용자들을 그룹핑하고, 각 사용자의 위치정보와 평가정보를 기반으로 시계열 분석 방법을 통하여 사용자 모델을 생성한다. 시스템의 성능을 평가하기 위해 테스트베드를 구축하고, 500개의 샘플 데이터를 생성하여 70%의 트레이닝 데이터와 30%의 테스트 데이터로 평가를 수행하였다. 처리시간 및 예측 정확도를 평가 한 결과, 예측 정확도는 기존 예측 알고리즘들과 비슷한 결과를 보였고, 처리시간은 평균 0.8초를 보여 실시간 서비스 환경에서 딜레이 타임 없이 사용할 수 있음을 보였다.