자기공명영상의 비지도 분할을 위한 통계적 모델기반 적응적 방법

김태우,Kim, Tae-Woo 한국정보처리학회 2000 정보처리논문지 Vol.7 No.1

본 논문은 MR 영상의 비지도 분할을 위하여 MDL원리를 이용한 통계적 모델기반의 적응적 방법을 제안한다. 이 방법에서 조직 영역을 MRF로 모델링함으로써 잡음에 대응하고, 창으로 정의되는 국소영역 내의 밝기값을 가우스 혼합으로 모델링함으로써 영상의 비균일성을 흡수한다. 분할 알고리즘은 ICM을 기반으로 하며 MAP를 근사적으로 추정하고, 모델 파라미터를 국소영역으로부터 구한다. 파라미터 추정과 분할을 위한 창의 크기는 MDL원리를 이용하여 영상으로부터 추정한다. 실험에서 제안한 방법이 특히 비균일성이 있는 MR영상의 분할에서 국소영역의 영상특성을 잘 반영하였으며, 기존의 방법보다 더 좋은 결과를 보여주었다. We present a novel statistically adaptive method using the Minimum Description Length(MDL) principle for unsupervised segmentation of magnetic resonance(MR) images. In the method, Markov random filed(MRF) modeling of tissue region accounts for random noise. Intensity measurements on the local region defined by a window are modeled by a finite Gaussian mixture, which accounts for image inhomogeneities. The segmentation algorithm is based on an iterative conditional modes(ICM) algorithm, approximately finds maximum ${\alpha}$ posteriori(MAP) estimation, and estimates model parameters on the local region. The size of the window for parameter estimation and segmentation is estimated from the image using the MDL principle. In the experiments, the technique well reflected image characteristic of the local region and showed better results than conventional methods in segmentation of MR images with inhomogeneities, especially.

치주탐침과 초음파기구를 이용한 구개 점막 두께 측정치의 비교연구

김태우,이재관,엄흥식,장범석,Kim, Tae-Woo,Lee, Jae-Kwan,Um, Heung-Sik,Chang, Beom-Seok 대한치주과학회 2006 Journal of Periodontal & Implant Science Vol.36 No.4

Maxillary palatal mucosa is the most frequently used donor site of the soft tissue for periodontal plastic surgery. In our study, thickness of the palatal mucosa between the mesial side of the maxillary first premolars and the distal side of the maxillary first molars was measured with a periodontal probe and an ultrasonic device in 30 young Korean adults. Using the data, the possibility of the clinical application of ultrasonic devices was evaluated. The results of this study were as follow; 1. The thickness of the palatal mucosa of the maxillary premolars is the thickest and that of the mid-palatal portion of the maxillary first molar is the thinnest. 2. The thickness of the palatal mucosal tissue increases from the gingival margin to the mid-palatal suture. 3. The measurements of the periodontal probe and the ultrasonic device revealed the strong positive correlations.

한국산 섬서구메뚜기속(Atractomorpha)의 분류학적 검토

김태우,Kim, Tae-Woo Korean Society of Applied Entomology 2009 한국응용곤충학회지 Vol.48 No.4

한국산 섬서구메뚜기속(Atractomorpha)의 분류학적 검토를 통해 섬서구메뚜기(Atractomorpha lata (Motschulsky, 1866))와 분홍날개섬서구메뚜기(신칭)(A. sinensis Bolivar, 1905) 두 종을 확인하였다. 이 중 분홍날개섬서구메뚜기는 한반도 남단의 섬 제주도와 가거도로부터 처음 보고되는 한국 미기록종이다. 두 종을 비교하여 동정할 수 있는 검색표, 기재, 사진 및 분포 정보를 제시하였다. A taxonomic review of the genus Atractomorpha Saussure in Korea is presented. Two species are identified, Atractomorpha lata (Motschulsky, 1866) and a new record A. sinensis Bolivar, 1905 which is reported from the far southern islands in Korea, Gageo-do and Jeju-do. A key, descriptions, habitus photographs of adults, and distributional information are provided.

주변도로 분포가 학교건축물의 소음실태에 미치는 영향에 관한 연구

김태우,이강국,홍원화,Kim, Tae-Woo,Lee, Kang-Guk,Hong, Won-Hwa 한국교육시설학회 2011 敎育施設 Vol.18 No.4

This study investigates interior and exterior environments and arrangement forms of school buildings from elementary to high school which were recently built in Daegu since the 7th Educational Curriculum. In addition, this study analyses how outside noise affects inside environment of schools. This study found that the noise level criteria of school facilities(such as exterior learning sites and outer walls of school buildings) adjacent to street of one side satisfiedly corresponded to the level and criteria, 65dB(A), of school health law. However, the noise level and vibration criteria of school facilities adjacent to street of two sides did not satisfiedly corresponded to the level or criteria, 65dB(A). In case of classrooms, the inner noise of educational facilities with windows closed and also close to both the street of one side and of two sides satisfiedly corresponded to the level or criteria. 55dB(A), of school health law. In spring and tall, the windows are more open them usual for ventilation, and leaving windows open can lead to noise from outside. Thus, it is urgent to prepare for this situation.

학교 건축물 전력소비의 기온감응도에 관한 연구

김태우,이강국,김호순,홍원화,Kim, Tae-Woo,Lee, Kang-Guk,Kim, Ho-Soon,Hong, Won-Hwa 한국교육시설학회 2011 敎育施設 Vol.18 No.5

In case of school buildings, energy consumption has been noticeably on the increase, along with the changes in outdoor temperature triggered by the improvement in national economic development and educational environments. Research on the characteristics of energy consumption in school buildings influenced by the changes in outdoor temperature is considered very significant in social aspects in that it will be fundamental to the suggestion of the alternatives, such as saving energy consumption in construction buildings and control of emitting carbon dioxide. In this regard, this study examined sensitivity to temperature of power consumption in school buildings, based on the changes of outdoor temperature for the past five years in the target buildings of elementary, middle and high schools and the amount of energy consumption. From the results, it has been believed that this study was very significant in terms of figuring out a quantitative, optimum level of energy consumption, maintenance of pleasant environments and functions, and the necessity of effective energy use and management in school buildings.

열간 압연용 고속도강 롤의 고온 특성

김태우,최진원,김동규 ( Tae Woo Kim,Jin Won Choi,Dong Gyu Kim ) 한국주조공학회 1996 한국주조공학회지 Vol.16 No.2

N/A High temperature properties such as hot hardness and thermal fatigue resistance of high speed steel roll of hot finishing mill have been investigated. Two kinds of roll having compositions, Fe-1.75%C-5.9%Cr-1.74%Mo-4.94%V-2.03%W(A specimen) and Fe-2.27%C-8.86%Cr-2.91%Mo-3.92%V-1.86%W(B specimen)were prepared for investigating the microstructure and crack propagation mode. A specimen has greater amounts of M_7C₃type carbides and less amounts of MC type carbides in comparison with B specimen. Hot hardness showed sudden decrease over 400℃, resulting in the hardness decrease of 50% at the temperature of 600℃, and showed little variation with time at 500℃ and 800℃. Thermal crack was developed at 550℃ in A specimen and 600℃ in B specimen.

다중 전달 경로 채널에서의 수중 디지털 통신을 위한 선 처리 기법

김태우,황아롬,성우제,임용곤,Kim, Tae-Woo,Hwang, A-Rom,Seong, Woo-Jae,Lim, Young-Kon 한국음향학회 2008 韓國音響學會誌 Vol.27 No.3

Signals in an underwater channel get distorted by multipath propagation. In this paper, pre-coding method is suggested which helps comprehending the signals with minimum equalization. The signals are transformed based on the knowledge of the impulse response of the channel. Proposed pre-coding method is tested by simulations based on the ray theory and through water tank experiments. In weak multipath environment, in case of an SNR of about 20 dB, BER is $10^{-3}{\sim}10^{-4}$, while in strong multipath environment, similar BER is achieved with SNR of about 30 dB. In order for the pre-coding method to be used for underwater vehicles, channel prediction method utilizing the waveguide invariant is suggested and tested. 수중 채널에서의 음파를 사용한 신호는 다중 전달 경로 현상에 의해 왜곡된다. 본 논문에서는 채널의 임펄스 응답을 바탕으로 신호를 미리 왜곡시켜 수신기에 도착했을 때 최소한의 등화만으로 신호를 받을 수 있는 선 처리 기법을 제안하였다. 그리고 음선 이론 기반 시뮬레이션과 수조 실험을 통해 제안한 기법의 성능을 검토하였다. 다중 전달 경로 현상이 약할 경우, SNR이 약 20 dB 일 때 BER이 $10^{-3}{\sim}10^{-4}$의 성능을 보였고 다중 전달 경로 현상이 심한 환경에서 SNR이 약 30 dB 일때 유사한 BER 성능을 보였다. 제안한 기법을 수중 운동체의 통신에 사용가능하도록 송수신기의 위치 변화에 따른 채널예측 기법을 제안하였고 그 성능을 검토하였다.

물리치료학과 대학생의 생활체육 참여실태에 관한 연구

김태우,이진,인태성,Kim, Tae-Woo,Lee, Jin,In, Tae-Seung 대한물리치료과학회 2018 대한물리치료과학회지 Vol.25 No.2

Background: The purpose of this study was to investigate a study about undergraduate students' participation in general sports. Method: A questionnaire survey was conducted on 200 students attending physical therapy at Gimcheon university students. four items of general characteristics, 2 conditions of sports for all, 2 activities of current sports for all, and 1 thing of sports for all, were extracted from the questionnaires of total 40 items. Result: In the present study, it was found that through the cross-sectional analysis of various variables related to life sports activities according to grade, sex, age and living cost level, students participated in less sports activities than other college students. And they participated in non-living sports activities such as appreciation and movie appreciation. In addition, it was found that factors such as watching sports games mainly affect the lives of women, especially with less sports activities, and men are more active at 20 to 28 years of age than those aged 20. Conclusion: These findings suggest that it is necessary to provide various opportunities to encourage the physical activities of female students and young students of the university and actively participate in sports for all.

고정밀 고속 하이브리드 온 칩 온도센서

김태우,윤진국,우기찬,황선광,양병도,Kim, Tae-Woo,Yun, Jin-Guk,Woo, Ki-Chan,Hwang, Seon-Kwang,Yang, Byung-Do 한국정보통신학회 2016 한국정보통신학회논문지 Vol.20 No.9

본 논문에서는 고정밀 하이브리드 온 칩 온도센서를 제안하였다. 제안된 온도센서에서는 SAR 타입 온도센서와 ${\Sigma}{\Delta}$타입 온도센서를 혼합하였다. SAR 타입 온도센서는 ${\Sigma}{\Delta}$타입 온도센서 보다 온도를 찾아가는 속도가 빠르지만 오차가 발생할 확률이 높은 단점이 있고, ${\Sigma}{\Delta}$ 타입 온도센서는 SAR 타입 온도센서 보다 정확하지만 속도가 느린 단점이 있다. 제안된 온도 센서는 두개의 온도 측정방법을 혼합하여 고정밀 고속 온도측정이 가능하다. 또한, 칩 제작 후 온도 오차 값을 메모리회로에 저장하여 온도 오차를 보상하는 회로를 포함하여 온도센서를 구현하였다. 제안된 온도센서는 $0.35{\mu}m$ CMOS 공정으로 제작되었다. 온도 정확도, 소비 전력, 칩 면적은 각각 $0.15^{\circ}C$, $540{\mu}W$, $1.2mm^2$였다. This paper presents a high accuracy and fast hybrid on-chip temperature sensor. The proposed temperature sensor combines a SAR type temperature sensor with a ${\Sigma}{\Delta}$ type temperature sensor. The SAR type temperature sensor has fast temperature searching time but it has more error than the ${\Sigma}{\Delta}$ type temperature sensor. The ${\Sigma}{\Delta}$ type temperature sensor is accurate but it is slower than the SAR type temperature sensor. The proposed temperature sensor uses both the SAR and ${\Sigma}{\Delta}$ type temperature sensors, so that the proposed temperature sensor has high accuracy and fast temperature searching. Also, the proposed temperature sensor includes a temperature error compensating circuit by storing the temperature errors in a memory circuit after chip fabrication. The proposed temperature sensor was fabricated in 3.3V CMOS $0.35{\mu}m$ process. Its temperature resolution, power consumption, and area are $0.15^{\circ}C$, $540{\mu}W$, and $1.2mm^2$, respectively.

사회 속의 의료, 의료 속의 사회 : 한국의 한의학과 중국의 중의학에 대한 의료인류학적 고찰

김태우,한창호,Kim, Tae-Woo,Han, Chang-Ho 대한한방내과학회 2012 大韓韓方內科學會誌 Vol.33 No.2

Objectives : One of the fundamental premises of medical anthropology is the interconnectedness of medicine and society. Recent ethnographies of medicine demonstrate that the interconnectedness of the social and the medical not just evokes relatedness of the two parties, but also emphasizes the agency of the constituents, mutually shaping and being shaped. Against this backdrop, this study attempts to anthropologically investigate Korean medicine in South Korea and traditional Chinese medicine (TCM) in China. Methods : The findings are based on anthropological studies of East Asian medicine employing long-term fieldwork about Korean Medicine and Traditional Chinese Medicine. Results : TCM is characterized by standardization, hospitalization, and scientization, by which simplification, collectivization, and biomedicalization prevail in contemporary traditional medicine in China. In contrast, Korean medicine is characterized by diversity, care delivery by individual private clinics, and a considerable distance from biomedicine. To understand the divergence of the two East Asian medicines, one should consider the social contexts intervening into the medical contents, such as the role of the state and dominant discourses in given historical periods. Conclusions : Korean medicine in South Korea and TCM in China demonstrate well the hybridity of the social and the medical, suggesting that, for more comprehensive understanding of the medical, the social should be paid attention to.