뇌교병변의 수술적 접근에 대한 증례보고

허성민,최하영,Heo, Seong-Min,Choi, Ha-Young 대한신경외과학회 2000 Journal of Korean neurosurgical society Vol.29 No.10

Although direct surgical treatment of the lesion in the pons may cause severe neurologic morbidity, safe route to minimize injuries of the important structures in the pons should be considered. The authors operated four cases of intrapontine lesions via safe approach route without causing severe neurologic complications. Two cases were intrapontine tumors and other two were intrapontine hematoma. An anaplastic astrocytoma($3{\times}3{\times}3cm$) located bilaterally in the pons was approached via midline of the median sulcus, and a metastatic tumor($1.5{\times}1.5{\times}1.5cm$) located at the left posterolateral aspect in the upper pons was approached via suprafacial space. Two cases of hematoma were evacuated via median sulcus, and supra- and infrafacial spaces. Preoperatively, quadriplegia, swallowing difficulty, diplopia, speech disturbance, and nystagmus were noted in a patient with an anaplastic astrocytoma. A patient with metastatic tumor showed mild right hemiparesis, right hemisensory disturbance, diplopia, and dizziness. Two patients with hematoma in the pons were comatous, and had contracted, fixed pupils. Postoperatively, a patient with an anaplastic astrocytoma recovered and a patient with a metastatic tumor showed temporary hemifacial palsy. Mental status was fully recovered normal even though facial palsy, diplopia, severe ataxia, dizziness, and tremor persisted in both patients with pontine hematoma. Careful operation based on the anatomical knowledge of the floor of the 4th ventricle is of prime importance in appraoching to the intrapontine lesion with minimal injuries of the eloquent structures during surgery.

SLS의 공정 파라미터 최적화에 관한 연구

허성민,오도근,최경현,이석희,Heo, Seong-Min,O, Do-Geun,Choe, Gyeong-Hyeon,Lee, Seok-Hui 대한기계학회 2000 大韓機械學會論文集A Vol.24 No.3

RP(Rapid Prototyping) technology is gaining its popularity in building a prototype in all industries. SLS(Slective Laser Sintering) is one of RP technologies, which is focused on tooling processes as well as three dimension solid model. There are several factors, the length and the cross-sectional area of a part, that have an effect on build setup in SLS process. In this paper, the computation on geometrical relationship is used to slice STL file and to estimate these factors. Based on these values, the build setup parameters such as the heating temperature, the laser power, and the powder cartridge feed rate are determined by neural network approaches. The test results show that the computation time is saved and the neural network approach is able to apply to get the optimal parameters of build process within an acceptable error rate.

사업장에서의 심리상담제도운영 사례

허성민,Heo, Seong-Min 한국산업간호협회 2007 한국산업간호협회지 Vol.14 No.2

텍스트 분석을 이용한 코로나19 관련 국내 논문의 주제 및 감성에 관한 융합 연구

허성민,양지연,Heo, Seong-Min,Yang, Ji-Yeon 한국융합학회 2021 한국융합학회논문지 Vol.12 No.4

본 연구에서는 코로나19 관련 연구논문의 연구주제를 탐색하고 동향을 검토하고 있다. 또한 감성분석을 통해 부정적인 어조가 강한 경고가 되는 주제들을 알아본다. 잠재 디리슐레 할당(LDA)를 이용하여 총 8개의 토픽을 발견하였고, 이를 구조적 토픽 모델링(STM)과 비교하여 비교적 안정적인 결과임을 확인하였다. 또한 k-means 군집 알고리즘을 통해 각 토픽별로 세부 연구주제를 발견하였고 주성분 분석을 이용하여 이를 시각적으로 표현하였다. 감성분석을 통해 각 토픽별 긍정적, 부정적인 단어들을 살펴보고 감성점수를 계산하여 연구논문의 주된 어조를 파악하였는데, 특히 생물 의학 관련, 국제적 역학관계, 심리적 영향과 관련된 연구에서 부정적인 어조가 강한 것으로 나타나 해당 부문에 대해서 주의와 관심이 요구된다. 향후 연구자들이 연구의 방향성을 탐색하고 정책결정자들이 연구지원 사업을 결정하는데 기초자료로 활용될 수 있을 것이다. The purpose of this study was to explore research topics and examine the trend in COVID19 related research papers. We identified eight topics using latent Dirichlet allocation and found acceptable validity in comparison with the structural topic model. The subtopics have been extracted using k-means clustering and plotted in PCA space. Additionally, we discovered the topics bearing negative tones and warning signs by sentiment analysis. The results flagged up the issues of the topics, Biomedical Related, International Dynamics and Psychological Impact. The findings could serve as a guideline for researchers who explore new research directions and policymakers who need to make decisions about which research projects to support.

Analysis of Research Topics and Trends on COVID-19 in Korea Using Latent Dirichlet Allocation (LDA)

Seong-Min Heo(허성민),Ji-Yeon Yang(양지연) 한국컴퓨터정보학회 2020 韓國컴퓨터情報學會論文誌 Vol.25 No.12

본 연구에서는 DBpia에 등록된 코로나19 관련 논문을 대상으로 연구 토픽을 밝히고 연구 변화추세를 검토한다. 잠재 디리슐레 할당(Latent Dirichlet Allocation) 알고리즘을 적용한 결과, 7개의 연구 토픽을 도출하였고, 각 토픽은 "International Dynamics", "Technology & Security", "Psychological Impact", "Biomedical-Related", "Economic Impact", "Online Education", "Religion-Related"에 관한 내용이었다. 또한 다범주 로짓모형을 사용하여 연구 토픽의 추세 변화를 살펴본 결과, 2020년 6월 전에는 국제적 역학관계 및 생물 의학 관련 논문이 주를 이루었다면, 이후에는 다양한 분야로 연구 주제가 확대되었다. 특히 경제적인 영향, 온라인 교육, 심리적인 영향에 관한 연구가 꾸준히 증가함을 확인할 수 있었다. 이러한 결과는 향후 코로나19 관련 공동 연구의 가이드 라인을 제시하고, 활발한 연구 활동을 위한 기초자료로 활용될 수 있을 것이다. This study aims to identify research topics and examine the trend of Covid19-related papers on DBpia. Applying latent Dirichlet allocation (LDA), we have extracted seven research topics, each of which concerns "International Dynamics", "Technology & Security", "Psychological Impact", "Biomedical-Related", "Economic Impact", "Online Education", and "Religion-Related". In addition, we used the multinomial logistic model to examine the trend of research topics. We found that the papers mainly cover topics related to "International Dynamics" and "Biomedical-Related" before June 2020, but the topics have become diverse since then. In particular, topics regarding "Economic Impact", "Online Education" and "Psychological Impact" has drawn increased attention of researchers. The findings would provide a guideline for collaboration in Covid19-related research, and could serve as a reference work for active research.

역공학에서의 Delaunay 삼각형 분할에 의한 점 데이터 감소

이석희,허성민,김호찬,Lee, Seok-Hui,Heo, Seong-Min,Kim, Ho-Chan 대한기계학회 2001 大韓機械學會論文集A Vol.25 No.8

Reverse engineering has been widely used for the shape reconstruction of an object without CAD data and the measurement of clay or wood models for the development of new products. To generate a surface from measured points by a laser scanner, typical steps include the scanning of a clay or wood model and the generation of manufacturing data like STL file. A laser scanner has a great potential to get geometrical data of a model for its fast measuring speed and higher precision. The data from a laser scanner are composed of many line stripes of points. A new approach to remove point data with Delaunay triangulation is introduced to deal with problems during reverse engineering process. This approach can be used to reduce a number of measuring data from laser scanner within tolerance, thus it can avoid the time for handling point data during modelling process and the time for verifying and slicing STL model during RP process.

역공학에서의 Delaunay 삼각형 분할에 의한 STL 파일 생성

이석희,김호찬,허성민,Lee, Seok-Hui,Kim, Ho-Chan,Heo, Seong-Min 대한기계학회 2002 大韓機械學會論文集A Vol.26 No.5

Reverse engineering has been widely used for the shape reconstruction of an object without CAD data and the measurement of clay or wood models for the development of new products. To generate a surface from measured points by a laser scanner, typical steps include the scanning of a clay or wood model and the generation of manufacturing data like STL file. A laser scanner has a great potential to get geometrical data of a model for its fast measuring speed and higher precision. The data from a laser scanner are composed of many line stripes of points. A new approach to remove point data with Delaunay triangulation is introduced to deal with problems during reverse engineering process. The selection of group of triangles to be triangulated based on the angle between triangles is used for robust and reliable implementation of Delaunay triangulation as preliminary steps. Developed software enables the user to specify the criteria for the selection of group of triangles either by the angle between triangles or the percentage of triangles reduced. The time and error for handling point data during modelling process can be reduced and thus RP models with accuracy will be helpful to automated process.

역공학에서의 노이즈가 포함된 측정데이터의 분할에 관한 연구

이석희,김호찬,허성민,Lee, Seok-Hui,Kim, Ho-Chan,Heo, Seong-Min 대한기계학회 2002 大韓機械學會論文集A Vol.26 No.3

The segmentation has been performed to the data of good quality in most cases, so the adoption of previous segmentation theory to the measured data with a laser scanner does not produce good result because of the characteristics of the data with noise component. A new approach to perform the segmentation on the scanned data is introduced to deal with problems during reverse engineering process. A triangular net is generated from measured point data, and the segmentation on it is classified as plane, smooth and rough segment. The segmentation result in each segment depends on the user-defined criteria. And the difference of the segmentation between the data of good quality and the data with noise is described and analyzed with several real models. The segment boundaries selected are used to maintain the characteristics of the parts during modeling process, thus they contribute to the automation of the reverse engineering.

텍스트 마이닝을 이용한 갑상선암 관련 국내 연구 추세 분석

이태경(Tae-Gyeong Lee),허성민(Seong-Min Heo),신승혁(Seung-Hyeok Shin),양지연(Ji-Yeon Yang) 한국컴퓨터정보학회 2018 韓國컴퓨터情報學會論文誌 Vol.23 No.12

In this paper, we propose a text-centered approach to identify the research trend of thyroid cancer in Korea. We incorporate statistical analysis, text mining and machine learning techniques with our clinical insights to find connective associations between terminologies and to discover informative clusters of literatures. The incidence of thyroid cancer in Korea increased rapidly in the 2000s, which fueled the debate regarding overdiagnosis, but recently the number of patients undergoing surgery has decreased significantly due to conscious reform efforts from various circles. We analyzed the abstracts and keywords of related research papers from DBpia. It was found that most were case reports in the 1980s, and some papers in the 1990s discussed the early detection of thyroid cancer by mass screening. While many papers focused on different diagnostic techniques and the detection of small cancers in the 2000s, many emphasized more on the quality of life of patients in the 2010s. There was an apparent change in the topics of thyroid cancer research over past decades. The results of this study would serve as a reference guide for current and future research directions.

카테킨 섭취와 지구성 운동이 Obese Zucker Rat의 골격근 형태별 GLUT-4 단백질과 혈청 지질 성분에 미치는 영향

이규성(Lee Gyu Seong),김문희(Kim Mun Hui),홍순모(Hong Sun Mo),허성민(Heo Seong Min),원상호(Won Sang Ho),김윤만(Kim Yun Man),윤지성(Yun Ji Seong),조준용(Jo Jun Yong) 한국사회체육학회 2003 한국사회체육학회지 Vol.20 No.2

Obesity and diabetes have been increased at an alaming rate in recent years and is now a worldwide health problem. We investigate the effects of 8wk feeding tea catechin which is natural polyphenolic compounds and 8wk treadmill exercise on the skeletal muscle GLUT-4 protein, serum glucose, insulin and lipids(TC, TG, HDL-C, LDL-C) in the insulin resistant obese Zucker rats(fa/fa). Male obese Zucker rats either remained sedentary(fa/fa, n=4), recieved catechins(5㎖=2.5g/250㎖(1%) day-1, fa/fa, n=4), performed treadmill exercise(fa/fa, n=4) or underwent both catechin supplementation and treadmill exercise(fa/fa, n=4) for 8wk. During oral glucose tolerance test(OGTT), treadmill exercise alone or in combination with catechins resulted in a significant lowering of the glucose, insulin and TC, TG, LDL-C responses compared with sedentary controls. Treadmill exercise or in combination with catechin group individually increased insulin-regulated glucose transporter(GLUT-4) in isolated soleus, plantaris and gastrocnemius muscle. The greatest expressions in GLUT-4 protein in these muscles were observed in the treadmill exercise group. Thus, enhancement in glucose transport in soleus, plantaris and gastrocnemius muscle due to treadmill exercise and in combination with catechin was related to enhanced GLUT-4 protein and decrease glucose, insulin and TC, TG, LDL-C. These results suggest that treadmill exercise and in combination with catechin individually may reduce the risk of associated diseases including diabetes and coronary heart disease.