World City로서 서울시 도시경쟁력 평가 연구

한봉수(Han, Bong-Soo),하성규(Ha, Seong-Kyu) SH도시연구원 2012 주택도시연구 Vol.2 No.1

World Cities are places with excellent infrastructures in terms of telecommunications, transport, cultural industries and information, all of which are requirements of globally competitive firms. As there is no one generally accepted definition of a “World City”, and the concept is in fact subject to ongoing debate, there are no “specific attributes” which define a world city. Rather, there is a range of attributes about which the debate revolves. Growing the world city is recognized as driving force of economic growth and has become a symbol of wealth of the country. Thus, in each country, the major city continually strives to remain competitive and Seoul also effort to make a competitiveness as well as other world cities. This study suggest ways to improve Seoul city's competitiveness, using selected objective competitiveness indicators compare with five major cities in the world. The results are as follows: First, Seoul has a small area and high population density so that land use and efficient expansion of infrastructure installation is required. Second, Seoul should be addressed to solve high residential cost and poor living condition. Third, Seoul needs to prepare to improve tax system and give a tax benefit more to global companies. Finally, Seoul should be attracted foreign tourists and develop tourism resources.

동수경사비 시험에 의한 토목섬유배수재의 장기막힘 특성

한봉수(Han Bong Soo),김용인(Kim Young In),김홍석(Kim Hong Suk),장연수(Jang Yeon Soo) 대한토목학회 2003 대한토목학회 학술대회 Vol.2003 No.10

저자장 자기공명영상 시스템에서의 위상대조도 혈관조영기법의 개발과 그 유용성에 대한 연구

이동훈,홍철표,이만우,한봉수,Lee, Dong-Hoon,Hong, Cheol-Pyo,Lee, Man-Woo,Han, Bong-Soo 한국의학물리학회 2012 의학물리 Vol.23 No.3

자기공명 혈관조영술은 혈관협착, 동맥류, 동정맥기형 등의 혈관질환 진단에 널리 사용되고 있다. 특히 위상대조도 자기공명 혈관조영술은 조영제를 사용하지 않는 자기공명 혈관조영술로서 혈관의 해부학적인 정보를 제공함과 동시에 혈류 속도측정이 가능하다. 본 연구에서는 저자장 자기공명영상 시스템에 적합한 2차원 및 3차원 위상대조도 혈관조영술의 펄스열을 개발하여 유속팬텀과 정상인의 뇌에 적용한 후 획득한 혈관영상과 위상분석을 통한 속도측정을 바탕으로 저자장 자기공명영상 시스템에서의 위상대조도 혈관조영술의 유용성을 평가하고자 한다. 2차원 및 3차원 위상대조도 혈관조영술을 제작된 유속팬텀과 인체 내에 적용하여 상시상 정맥동, 곧은 정맥동 및 두 혈관의 합류지점에 대한 속도측정을 시행하였다. 결과로서 2차원 위상대조도 혈관조영술의 사용은 큰 혈관에 대해서는 높은 가시도를 나타내지만, 작은 혈관에 대한 가시도는 상대적으로 저하됨을 확인할 수 있었다. 3차원 위상대조도 혈관조영술을 사용한 혈관영상은 2D PC MRA 영상에 비해 큰 혈관은 물론이고 작은 혈관에 대한 가시도가 향상되었으나 작은 혈관에서 영상의 신호가 불균일하여 작은 혈관의 진단에 사용하기에는 적합하지 않았다. 한편 2차원 위상대조도 혈관조영술을 통한 영상에서 큰 혈관의 가시도는 혈류속도를 측정하기에 충분했다. 측정된 결과는 상시상 정맥동의 경우 $25.46{\pm}0.73cm/sec$, 곧은 정맥동의 경우 $24.02{\pm}0.34cm/sec$, 상시상 정맥동과 곧은 정맥동의 합류지점의 경우 $26.15{\pm}1.50cm/sec$으로 나타났으며 이는 앞선 연구결과에서 알려진 전체 심장운동주기를 고려한 정상인들의 각 해당 부위별 혈류속도의 오차범위 내에 포함되는 좋은 결과를 나타내었다. 앞선 결과들을 토대로 본 연구는 현재 국내에서 제작하여 보급중인 저자장 자기공명영상 시스템에서 위상대조도 혈류영상화 기법의 적용 및 응용 가능성을 보여주고 있으며 이를 실용화하기 위한 중요한 기초자료를 제공할 수 있을 것이다. Magnetic resonance angiography (MRA) techniques are widely used in diagnosis of vascular disorders such as hemadostenosis and aneurism. Especially, phase contrast (PC) MRA technique, which is a typical non contrast-enhanced MRA technique, provides not only the anatomy of blood vessels but also flow velocity. In this study, we developed the 2- and 3-dimensional PC MRA pulse sequences for a low magnetic field MRI system. Vessel images were acquired using 2D and 3D PC MRA and the velocities of the blood flow were measured in the superior sagittal sinus, straight sinus and the confluence of the two. The 2D PC MRA provided the good quality of vascular images for large vessels but the poor quality for small ones. Although 3D PC MRA gave more improved visualization of small vessels than 2D PC MRA, the image quality was not enough to be used for diagnosis of the small vessels due to the low SNR and field homogeneity of the low field MRI system. The measured blood velocities were $25.46{\pm}0.73cm/sec$, $24.02{\pm}0.34cm/sec$ and $26.15{\pm}1.50cm/sec$ in the superior sagittal sinus, straight sinus and the confluence of the two, respectively, which showed good agreement with the previous experimental values. Thus, the developed PC MRA technique for low field MRI system is expected to provide the useful velocity information to diagnose the large brain vessels.

자기공명영상을 이용한 근육 단면적 측정법의 활용을 위한 영상왜곡보정

홍철표,이동훈,박지원,한봉수,Hong, Cheol-Pyo,Lee, Dong-Hoon,Park, Ji-Won,Han, Bong-Soo 대한물리치료학회 2012 대한물리치료학회지 Vol.24 No.2

Purpose: The purpose of this study is to explore the importance of the image distortion correction in the cross sectional area measurement for the iliopsas muscle, tensor fasciae latae muscle, gluteus maximus muscle and the knee extensor muscles, by using (magnetic resonance imaging) MRI. Methods: This study was performed using an open 0.32T MRI system. To estimate the image distortion, T1 images for an AAPM homogeneity/linearity phantom were acquired, and the region in which the maximum geometric distortion was less than or equal to the pixel size (1.6 mm) of the images, it was defined as the distortion correction-free region. The T2 images for a human subject's pelvis and thigh in normal positions were obtained. Then, after the regions of interest in the pelvis and thigh were moved into the distortion correction-free region, T2 images for the pelvis and thigh were scanned with the same imaging parameters used in the previous T2 imaging. The cross-sectional areas were measured in the two T2 images that were obtained in the normal position, and the distortion correction-free region, as well as the area error caused by geometric image distortion was calculated. Results: The geometrical distortion is gradually increased, from the magnet center to the outer region, in axial and coronal plane. The cross-sectional area error of gluteus maximus muscle and the knee extensors was as high as 9.27% and 3.16% in before and after distortion correction, respectively. Conclusion: The cross-sectional area of the muscles that suffered from the geometrical distortion is necessary to correct for the estimation of the intervention.

전력 케이블용 접속 슬리브의 구조 및 접속 방법에 따른 특성 연구

김영범(Young-Bum Kim),한봉수(Bong-Soo Han),류정현(Jeong-Hyun Ryu) 대한전기학회 2009 대한전기학회 학술대회 논문집 Vol.2009 No.7

초고압 전력 케이블용 도체 접속을 위한 접속방법으로 압축형(compressing type), 용접형(welding type), 압축-용접형(CW type; compressing-welding type)의 슬리브는 물론 동과 알루미늄의 이종(nonidentical materials) 접속을 위한 슬리브를 개발 하였으며, 전기적, 기계적으로 검증된 제품 개발을 위하여, 슬리브의 구조 변경과 접속 방법의 차이뿐 아니라 접속 전후의 응력 평가를 위해 슬리브 시편의 인장시험(tensile strength) 결과에 따른 슬리브 제작 및 시험을 진행하였다. 신뢰성 있는 제품 개발과 데이터를 얻기 위하여 초고압용 지중 고압 케이블을 시험 시료로 적용하여 시험 선로(test loop)를 구성하였으며, 이를 통하여 구조와 재질에 따른 접속 방법, 이상 온도 상승 또는 국부적인 고온 부위 발생 여부 등의 전기 시험 및 열싸이클 전압 시험(heating cycle voltage test) 조건을 설정하여 시험 전후의 열신축 등 전기적, 기계적 특성을 평가하였다. 접속 슬리브의 구조 및 재질에 따른 위치별 발열 양상을 체크하였으며, X-ray 장비를 이용하여 슬리브 내부의 압축 및 충진 정도를 점검함으로써 기존 접속 슬리브 보완은 물론 개발된 접속 슬리브의 설계 기준 및 안전율을 설정 할 수 있었다.

고유전율 재료를 사용한 Super Compacted Cold Shrinkable Joint 개발

류정현(RYU JEONG HYUN),한봉수(HAN BONG SOO),배동호(BAE DONG HO) 대한전기학회 2012 대한전기학회 학술대회 논문집 Vol.2012 No.5

거시경제변동이 가계신용 및 주택가격에 미치는 영향 연구

오정석 ( Jung Seok Oh ),한봉수 ( Bong Soo Han ),김윤중 ( Yoon Joung Kim ) 한국지역개발학회 2011 韓國地域開發學會誌 Vol.23 No.3

With debits of the majority of households continuously increasing, external macro economic impacts, such as interest rate increases, rising inflation pressure and reducing incomes, heighten a possibility of debt default of general households. This means, given the fact that debts and assets of most households in Korea are disproportionately based on their houses, it is highly likely that the local housing market`s instability can be triggered by potential house price drops. Hence, this study is designed to offer a basis to evaluate future housing approaches and housing policy to stabilize household credit and local housing market by finding out the correlation between macro economic factors and household credit and housing prices. As to analysis methods, in this study a stress test model was adopted and analyzed, using CreditPortfolioView devised by Mckinsey so as to find out the correlation between macro economic factors and household credit and housing prices. Also, in accordance with shock scenarios encompassing macro economic factors, such as interest rates, housing prices, liquidity and incomes, simulations were carried out so as to check how households` default rates influence housing prices. The study is structured in an order that the characteristics of household credit in Korea were defined first, and, then, correlations between macroeconomic factors and household credit and housing prices were analyzed. Afterwards, in the study, the author suggests polices to ensure stability of household credit and housing market.

쥐 해마에서 글루타메이트의 시간에 따른 변화가 급성 스트레스 연구에 미치는 영향 : 자기공명분광학을 이용한 연구

연제형(Jehyeong Yeon),윤창수(Chang-Soo Yun),황윤호(Yoonho Hwang),백현만(Hyeon-Man Baek),김동윤(DongYoun Kim),한봉수(Bong Soo Han) 대한전자공학회 2021 대한전자공학회 학술대회 Vol.2021 No.6

It was reported that rodents were significantly influenced by stress from experimental procedure and by isoflurane anesthesia. Therefore, in MRS experiments in the hippocampus of normal mice, the concentrations of Glu and tCho were observed to decrease over time. Glu is a potential stress biomarker and its concentration increases with stress. The purpose of this study is to investigate the effect of the time delay that may occur during 1H-MRS experiments on acute stress studies by comparing the control group and the stress group. 20 C57BL/6N male mice were grouped into the control group and the stress group. The stress group mice were exposed to acute constrain stress, and 1H-MRS data were obtained from the left hippocampus, and the difference in the concentration of metabolites due to stress was compared. We found that the statistical significance of the difference in Glu concentration between the two groups changed if there was a difference of about 17 minutes in the data collection time between the two groups. In conclusion, the results of this study suggest that it is necessary to avoid the difference in the timing of data collection between the control and experimental groups in stress studies.

몬테카를로 영상모의실험 코드를 이용한 Gd$_2$O$_2$S(Tb) 섬광체 및 광센서 어레이 기반 디지털 X-선 영상시스템의 화질평가

정만희,정인범,박주희,오지은,조효성,한봉수,김신,이봉수,김호경,Jung, Man-Hee,Jung, In-Bum,Park, Ju-Hee,Oh, Ji-Eun,Cho, Hyo-Sung,Han, Bong-Soo,Kim, Sin,Lee, Bong-Soo,Kim, Ho-Kyung 대한의용생체공학회 2004 의공학회지 Vol.25 No.4

in this study, we developed a Monte Carlo imaging simulation code written by the visual C$\^$++/ programing language for design optimization of a digital X-ray imaging system. As a digital X-ray imaging system, we considered a Gd$_2$O$_2$S(Tb) scintillator and a photosensor array, and included a 2D parallel grid to simulate general test renditions. The interactions between X-ray beams and the system structure, the behavior of lights generated in the scintillator, and their collection in the photosensor array were simulated by using the Monte Carlo method. The scintillator thickness and the photosensor array pitch were assumed to 66$\mu\textrm{m}$ and 48$\mu\textrm{m}$, respertively, and the pixel format was set to 256 x 256. Using the code, we obtained X-ray images under various simulation conditions, and evaluated their image qualities through the calculations of SNR (signal-to-noise ratio), MTF (modulation transfer function), NPS (noise power spectrum), DQE (detective quantum efficiency). The image simulation code developed in this study can be applied effectively for a variety of digital X-ray imaging systems for their design optimization on various design parameters. 본 연구에서는 디지털 X-선 영상시스템의 최적화 설계를 위하여 몬테카를로 방법을 이용한 영상모의실험용 코드를 visual $C^{++}$ 프로그래밍 언어를 사용하여 개발하였다. 디지털 X-선 영상시스템으로 Gd$_2$O$_2$S(Tb) 섬광체 및 광센서 어레이를 고려하였으며, 일반적인 실험 환경을 모사하기 위해 2차원 평행 그리드를 포함시켰다. X-선과 피사체, 그리드 및 섬광체와의 반응, 그리고 섬광체에서 발생된 빛의 거동 및 광센서 어레이에서의 수집을 몬테카를로 방법을 이용하여 모사하였다. Gd$_2$O$_2$S(Tb) 섬광체의 두께는 66$\mu\textrm{m}$로 설정하였으며, 광센서 어레이의 픽셀 피치는 48$\mu\textrm{m}$ 그리고 픽셀의 포맷은 256${\times}$256으로 가정하였다. 다양한 모의실험조건에서 X-선 영상을 획득한 후 객관적인 영상시스템의 성능평가 지표인 SNR(signal-to-noise ratio), MTF(modulation transfer function), NPS(noise power spectrum), DQE(detective quantum efficiency) 등을 계산하였으며, 이를 통해 화질을 평가하였다. 본 연구에서 개발된 영상모의실험 코드는 다양한 디지털 X-선 영상시스템에 대해 여러 설계변수들에 대한 성능을 예측함으로써 영상시스템 최적설계에 활용될 수 있다.

능동 및 수동 운동과 기능적 전기자극에 의한 대뇌 피질의 활성화

권용현 ( Yong Hyun Kwon ),장성호 ( Sung Ho Jang ),한봉수 ( Bong Soo Han ),최진호 ( Jin Ho Choi ),이미영 ( Mi Young Lee ),장종성 ( Jong Sung Chang ) 한국전문물리치료학회 2005 한국전문물리치료학회지 Vol.12 No.2