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.

Web 2.0 기반 국가기준점 어플리케이션 설계

김태우,김정욱,서용철,Kim, Tae-Woo,Kim, Jyung-Wuk,Suh, Yong-Cheol 한국공간정보시스템학회 2009 한국공간정보시스템학회 논문지 Vol.11 No.3

삼각점, 수준점 등 국내에서 위치를 결정하는데 기본이 되는 모든 기준점은 공간정보의 기준이자 기반이 되기 때문에, 합리적이고 효율적이며, 지속적으로 관리되어야 한다. 한편 IT 및 통신기술이 발달함에 따라 공간정보를 다루는 모든 기술이 함께 발전하고 있으며, 모바일 디바이스의 대중화와 웹 2.0 환경이 구축됨에 따라 기준점의 관리를 실시간으로 가능케 하는 기술이 요구되고 있다. 이는 사용자의 편의를 보장하고 과학적이며 체계적인 기준점 관리를 도모한다. 본 연구에서는 웹 2.0 환경 하에서 Ajax 기반의 웹 어플리케이션을 설계하여 실시간으로 갱신되는 기준점 정보의 원활한 소통을 지원하고, 영상정보를 함께 제공함으로써 사용자 접근성을 강화하는 기술을 개발하였다. As a surveying standard of a nation, the Korean geodetic control points such as triangulation points and benchmarks require continuous and effective management toward a spatially enabled society. As the developments of information technologies, use of mobile devices like PDA (personal digital assistant) has been increasing and the Web 2.0 environment became an important part of GIS. In this context, the management systems for national geodetic control points should be upgraded in accordance with the current trend, particularly for more interactive user-interface on the Web 2.0. This paper describes the framework design and prototype implementation of a Web 2.0 GIS application for the management of Korean geodetic control points. Our system enables a real-time update of the control point information and provides aerial photos on vector maps using Ajax(Asynchronous JavaScript and XML) techniques.

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.

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.

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.

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.

장중복증의 임상적 고찰

김태우,정풍만,Kim, Tae-Woo,Jung, Poong-Man 대한소아외과학회 2004 소아외과 Vol.10 No.1

Intestinal duplication is a rare congenital anomaly. The diagnostic approach is difficult because of the differences in its location and clinical presentation. To evaluate the diagnostic as well as the therapeutic approaches in children, the medical records of 20 patients with intestinal duplications which had been operated upon from July 1980 to October 2002 were analyzed, retrospectively. The range of age was from 1 day to 11 years. The variables, such as age, sex, clinical presentation, diagnostic method, localization, anatomic type, treatment, complication, and combined anomalies were analyzed. Most of the cases were presented as incidental finding. The majority of the duplications except hindgut were cystic type. Treatment included segmental intestinal resection, excision of the lesion without intestinal resection, and septotomy. Seventy-five percent of the patients were detected before 1 year of age. The anatomic type of the lesion was closely related with its location. The cases of hindgut were almost always tubular type except 1 case. Clinical presentation was related to age, location, and anatomic type. There were no specific diagnostic methods. Perfect localization and application of appropriate operation are the most important requirements for successful treatment.

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.

행정구역 자율통합의 추진 과정에서 나타난 주민인식도 분석 : 괴산군과 증평군 사례를 중심으로

김태우,한형서,Kim, Tae-Woo,Han, Hyung-Seo 한국국토정보공사 공간정보연구원 2016 지적과 국토정보 Vol.46 No.1

본 연구는 괴산군과 증평군의 행정구역 자율통합 과정에서 나타난 주민인식도의 분석이다. 이 설문에서 보면 괴산군민은 통합에 찬성을 하였고, 증평군민은 반대를 하였다. 이 연구 결과는 2009년과 2012년에 통합을 추진하면서 나타난 여론조사 결과와 대동소이하게 분석되었다. 괴산군과 증평군의 통합을 찬성한 이유로는 통합이 양 군의 체계적인 행정서비스와 행정절차의 편리성을 가져올 것이라고 기대하였고, 또한 주민 편의시설의 확충과 지역 문화축제의 확대 및 지역 경제발전에 기여할 것이라고 기대하였다. 그리고 행정구역의 통합이 가능하다면 정치권에 미치는 영향은 경상경비중복지출의 절감, 불필요한 정책공약 및 남발의 감소를 기대하였다. 반면 통합에 반대하는 이유로는 독자적인 행정구역이 지역 경제발전에 도움이 되고, 또한 대다수의 지역 주민들이 통합의 필요성을 크게 느끼지 못한다는 데 있었다. 오히려 독립적인 행정구역이 지역문화축제의 홍보와 균형발전에 유익한 것으로 인식되었다. 그럼에도 불구하고 양 지역의 주민들은 군의 향후 발전 방향에 대하여 인구 유입의 필요성과 지역경제의 활성화가 가장 시급한 것으로 인식하였다. 따라서 양 지역민들은 상호 인접한 지역연합체인 중원문화권을 형성해 인근 광역자치단체들과 상호협력 및 보완적인 관계에서 독자적인 지역 경제를 활성화시키는 데 많은 기대를 하는 것으로 분석되었다. This study analyzes the awareness of citizens towards the autonomous integration process between Goesan-gun and Jeungpyoung-gun. According to the survey, the citizens of Goesan-gun agreed on the integration, but the citizens of Jeungpyoung-gun disagreed on the plan. This result is different from the findings of the opinion surveys which were conducted in 2009 and 2012. The reason why some citizens agreed on the integration is that the integration will help more with the systematic administration service and the convenience of administrative process. Also the citizens are expecting the expansion of the convenient facilities and the economic growth through the local festivals. In the political view, it will cut the operating cost of the two provinces. However, there are some reasons for the disagreement of the integration. The first reason is that the independent development will be more beneficial for each province. And it will be more effective if each province separately promotes the local festivals to be more productive. Nevertheless, the citizens in both areas admit the necessity of the population influx and elevating the local economy for both provinces. These two areas are expecting to have the autonomous local economy and the complementary and competitive relationship with the nearby metropolitan councils while building the Jungwon cultural zone which is supported by the regional association.

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.