비전형적 진행 양상을 보인 거대 융기피부섬유육종

최창민 ( Chang Min Choi ),조희령 ( Hee Ryung Cho ),유박린 ( Bark Lynn Lew ),심우영 ( Woo Young Sim ) 대한피부과학회 2010 대한피부과학회지 Vol.48 No.4

Dermatofibrosarcoma protuberans is a slow-growing malignant tumor of soft tissue usually occurring on the trunk or proximal extremities. It commonly affects 20 to 50-year-old persons and measures less than 5 cm in diameter. It starts as an erythematous indurated papule or plaque, and can enlarge over several years. It shows aggressive local invasion but a low rate of distant metastasis. A 63-year-old female presented with a 5-month-history of a rapidly growing cutaneous lesion on the abdomen. Physical examination revealed an 8×10 cm sized, violaceous, polypoid firm mass superimposed on the violaceous to brownish indurated plaque and surrounding nodule. Histopathologic examination showed an infiltrating mass composed of spindle shaped cells that were arranged in a storiform growth pattern within the whole layer of dermis. The cellular mass extended into the subcutaneous fat layer in a honeycomb pattern. The tumor cells were positive for CD-34 stain. Additionally, some areas of tumor showed myxoid change. Magnetic resonance imaging demonstrated a homogenously-enhancing, and protruded mass invading the subcutaneous fat layer. The diagnosis of dermatofibrosarcoma protuberans was established and it was treated by wide local excision. We report a case of giant, polypoid dermatofibrosarcoma protuberans presenting with rapid growth. (Korean J Dermatol 2010;48(4):318~321)

우황청심원이 정상인의 심박변이도에 미치는 영향

최창민,선종주,김석민,정재한,이승엽,최원우,홍진우,박성욱,정우상,문상관,박정미,고창남,조기호,김영석,배형섭,Choi, Chang-Min,Sun, Jong-Joo,Kim, Seok-Min,Jung, Jae-Han,Lee, Seung-Yeup,Choi, Won-Woo,Hong, Jin-Woo,Park, Seong-Uk,Jung, Woo-Sang,Moon, Sa 대한한방내과학회 2007 大韓韓方內科學會誌 Vol.28 No.4

Objectives : This study was conducted to assess the effect of Uhwangchungsimwon on the autonomic nervous system. Methods : Eligible subjects were enrolled from healthy people in their 20s-30s. They were divided into two groups, the UC group (n=22) and the control group (n=20). We monitored ECG from 14:00 to 18:00 in both groups. In the UC group, subjects were administered UC at 15:00. HRV analysis was conducted at 14:00, 16:00, and 17:00 for 512 seconds. Results : The degree of LF/HF ratio change was significantly higher in the UC group at 1 hour after administration. Conclusion : We suggest Uhwangchungsimwon may be useful for stabilization of the autonomic nervous system by activating parasympathetic nerve in healthy people.

UIA 라이브러리를 이용한 GUI 테스트 자동화 방법

최창민,정인상,김현수,Choi, Chang-Min,Chung, In-Sang,Kim, Hyeon-Soo 한국정보처리학회 2011 정보처리학회논문지D Vol.18 No.5

기존의 GUI 테스트 도구들은 테스트 케이스 준비 및 테스트 수행시 테스터의 개입을 많이 요구한다. 이러한 문제를 개선하기 위해 본 논문에서는 GUI 테스트 케이스를 구축할 수 있는 새로운 방법을 제안한다. 이 방법은 GUI 내에서 잠재적인 제어 흐름을 식별하여 GUI맵을 구성하는 방법이다. .NET Framework에서 제공하는 UIA 라이브러리는 GUI 컨트롤 정보를 추출하는 과정에 사용되며, 이를 통해 GUI맵을 구성한다. 추출된 GUI 컨트롤 정보를 기반으로 그룹화 매커니즘을 사용하여 테스트 시나리오를 생성한다. 다양한 테스트 시나리오는 어떤 GUI 컨트롤에 대해 그 컨트롤이 속하는 그룹에서 다른 컨트롤을 선택하여 그것을 대체함으로써 자동 생성된다. 기존의 GUI 테스트 도구들은 테스트 커버리지를 지원하지 않았지만, 이 논문에서 제안하는 방법은 GUI맵을 사용하여 실행되었거나 실행되지 않은 시나리오 흐름을 파악할 수 있으므로 이를 통해 테스트 커버리지를 측정할 수 있다. When preparing test cases and running the test the existing GUI test tools require many tester's interventions. To cope with such problem this paper suggests a new method to build test cases for GUI test. This method identifies the potential control flows within the GUI and constructs the GUI map. The UIA library in .NET Framework is used to extract information about the GUI controls and the GUI map is constructed by the extracted information. Test scenarios are generated from the extracted information about the GUI controls using the grouping mechanism. Based on the grouping mechanism, various test scenarios which are test cases in GUI tests can be made by replacing a GUI control by another one in the same group. The existing GUI test tools do not support the concept of test coverage. Since, however, our method survey which part of the GUI map is executed or not during running the test, the test coverage can be measured by using the GUI map.

Tyr-Ala 펩타이드 이온의 전자전이 분광 연구

최창민,권장숙,김환진,윤태오,양민오,김남준,Choi, Chang-Min,Kwon, Jang-Sook,Kim, Hwan-Jin,Yoon, Tae-Oh,Yang, Min-O,Kim, Nam-Joon 대한화학회 2007 대한화학회지 Vol.51 No.4

양성자가 결합된 티로신-알라닌 펩타이드 이온(YAH+)의 전자전이 광분해 스펙트럼을 이 이온의 가 장 낮은 에너지의 전자전이가 관측되는 34500~36700 cm-1 영역에서 얻었다. YAH+ 이온은 전자분무 이온화법 을 이용하여 기체상에서 생성하였고 생성된 이온의 저장 및 검출은 4중극자 이온 트랩과 반사판 비행시간 질 량분석기가 결합된 혼성 질량분석기를 이용하였다. 이온 트랩에 저장된 YAH+ 이온에 레이저 펄스를 쪼여주어 광분해 반응을 유발한 후 그 광분해 정도를 레이저 파장에 따라 측정함으로써 전자전이 광분해 스펙트럼을 얻 었다. 이 스펙트럼에는 두 개의 넓은 폭을 가진 피크가 관측되었으며 시간-의존 밀도함수 법(Time-dependent density functional method, TD-DFT)을 이용한 계산을 통해 각각 YAH+의 S1과 S2 전이로 지정하였다. 관측된 피 크들의 넓은 폭은 상온에서 존재 가능한 YAH+의 여러 이형태체들의 전자전이 간 겹침과 또한, 상온에서 형성 된 이온의 들뜬 진동에너지 준위로부터의 전자전이 즉, 뜨거운 띠(hot band)들 때문인 것으로 설명하였다. Electronic photofragmentation spectrum of protonated tyrosine-alanine dipeptide ions(YAH+) was obtained in the wavenumber region of 34500~36700 cm-1 using a quadrupole ion trap time-of-flight mass spectrometer (QIT-TOFMS). YAH+ ions were produced by electrospray ionization, stored in the ion trap and then irradiated by ultraviolet laser pulses which induced photofragmentation of the ions. The electronic photofragmentation spectrum was obtained by monitoring the photodissociation yields of YAH+ ions as a function of the laser wavelength. The spectrum exhibited two broad peaks which were assigned as S1 and S2 by theoretical calculations using a time-dependent density functional method. The broad widths of the peaks in the spectrum were explained by the overlaps of the peaks originated from various conformers of YAH+ ions which were present in the gas phase at room temperature and also by the contributions of the hot bands.

웨이블릿 변환을 이용한 Depth From Defocus

최창민,최태선,Choi, Chang-Min,Choi, Tae-Sun 대한전자공학회 2005 電子工學會論文誌-SC (System and control) Vol.42 No.5

본 논문에서는 CCD 카메라를 이용하여 획득된 영상들 간의 상대적인 열화(Blur)를 이용하여 물체의 3차원 형상 및 거리 정보를 얻을 수 있는 Depth From Defocus(DFD) 방법을 제안한다. 기존 논문의 주파수 영역에서 디포커스(Defocus) 연산자를 구하는 역필터링(Inverse filtering) 방법은 정확도가 떨어지고, 윈도우 효과(Windowing effects) 및 영상의 경계 효과(Border effect)와 같은 단점이 있었다. 또한 일반적인 영상은 비정체성 (Nonstationary)이기 때문에, 임의의 텍스처에 대한 가우시안(Gaussian) 및 라플라시안(Laplacian) 연산자 등의 필터를 이용하는 디포커스 방법의 추정값은 결과가 좋지 않다. 이러한 문제점들을 해결하기 위해 지역적 분석과 함께 다양한 크기의 윈도우를 제공하는 웨이블릿 변환을 이용한 DFD 방법을 제안한다. 복잡한 텍스처 특성을 갖는 영상의 깊이 추정을 위해서는 웨이블릿 분석을 사용하는 것이 효과적이다. Parseval의 정리에 의해 영상 간의 웨이블릿 에너지의 비율이 열화 계수(Blur parameter) 및 거리와 관련 있음을 증명하였다. 제안된 DFD 알고리즘의 성능을 계산하기 위해 실험은 종합적이며 실제적인 영상을 이용하여 행하였다. 본 논문의 DFD 방식은 기존의 DFD 방법보다 RMS 에러 측면에서 정확한 결과를 보였다. In this paper, a new method for obtaining three-dimensional shape of an object by measuring relative blur between images using wavelet analysis has been described. Most of the previous methods use inverse filtering to determine the measure of defocus. These methods suffer from some fundamental problems like inaccuracies in finding the frequency domain representation, windowing effects, and border effects. Besides these deficiencies, a filter, such as Laplacian of Gaussian, that produces an aggregate estimate of defocus for an unknown texture, can not lead to accurate depth estimates because of the non-stationary nature of images. We propose a new depth from defocus (DFD) method using wavelet analysis that is capable of performing both the local analysis and the windowing technique with variable-sized regions for non-stationary images with complex textural properties. We show that normalized image ratio of wavelet power by Parseval's theorem is closely related to blur parameter and depth. Experimental results have been presented demonstrating that our DFD method is faster in speed and gives more precise shape estimates than previous DFD techniques for both synthetic and real scenes.

유/무기 하이브리드 코팅액에 의한 냉간압연강판의 내식특성

김정량(Jung Ryang Kim),최창민(Chang Min Choi),남기우(Ki Woo Nam) 대한기계학회 2012 大韓機械學會論文集A Vol.36 No.4

종래 아연의 부식 속도를 줄이는 가장 일반적인 방법은 Cr??를 도포하여 화학적으로 개조하는 것이었다. 그러나 Cr??는 현재 환경 보호법 때문에 사용이 제한되어 있다. 따라서 자자들은Si를 가지는 유/무기 용액에 대한 아연도금강판의 최적 조건을 연구하였다. 최적 내식성은 190 ℃에서 5분간 열처리한 조건으로 나타났다. 본 연구에서는 내식성 평가를 위하여 우레탄 용액(Urethane 20 wt.% ; S-700), Si를 가지는 유 무기 용액(Si polysilicate 10 wt.% + Urethane 10 wt.% LR-0317) 및 Si와 Ti를 가지는 2종류의 유/무기 용액(Si polysilicate 7 wt.% + Urethane 13 wt.% + Ti amorphous 0.5 wt.% ; LR-0727(1), Si polysilicate 7 wt.% + Urethane 7 wt.% + Ti amorphous 0.5 wt.% + epoxy 6 wt.% ; LR-0727(2))을 사용하였다. 내식성 평가는 냉간압연 강판을 사용하여 염수분무 시험으로 실시하였다. 7시간의 염수 분무 시험에서 LR-0727(1)과 LR-0727(2) 용액이 냉간 압연 강판에 대하여 우수한 내식성을 나타내었다. In the past, a very popular way to reduce the corrosion rate of zinc was the use of chemical conversion layers based on Cr??. However, the use of chromium salts is now restricted because of environmental protection legislation. Previous research investigated the optimum corrosion resistance of galvanized steel treated with an organic/inorganic solution containing Si. The result showed that the optimum corrosion resistance occurred by heat treatment of 190℃ in 5 min. In this study, one organic and three hybrid organic/inorganic coating solutions were applied to cold-rolled (CR) carbon steel. The coatings were then evaluated for corrosion resistance under a salt spray test. The coating solutions examined in this study consisted of urethane-only, urethane-Si, urethane-Si-Ti, and urethane-Si-Ti-epoxy. The results of the 7 h salt spray test showed that the urethane-Si-Ti and urethane-Si-Ti-epoxy coating solutions had superior corrosion resistance on CR steel.

유/무기 하이브라드 코팅액에 의한 냉간압연강판의 열처리 온도에 따른 내식특성

남기우(Ki Woo Nam),김정량(Jung Ryang Kim),최창민(Chang Min Choi) 한국해양공학회 2011 韓國海洋工學會誌 Vol.25 No.6

The demand for cold rolled steel (CR) for structural members is gradually increasing. If no surface treatment (coating for corrosion resistance) for CR is conducted, its use is very limited because CR is vulnerable to corrosion. Therifore, we need to develop a coating solution to provide high corrosion resistance for CR. In this study, an organic/inorganic coating solution with Si and Ti (Si polysilicate 7 wt. % + Urethane 13 wt. % + Ti amorphous 0.5 wt. %; LR-0727(1)) was used to evaluate the corrosian resistance of CR under a salt spray test. The specimens with the LR-0727(1) coating were heat treated in a drying oven at 120-210 ℃ for 5 min. The corrosion resistance was investigated using a salt spray test of 7 h. In addition, an adhesive test was conducted. Rust showed under a heat treatment of 150 ℃, but no vestiges were found over 160 ℃. The specimens with heat treatment at 160 ℃ or nwre did not experience delamination. From these results, it is considEred that the temperature limit for optimum heat treatment is 160 ℃ considering energy efficiency.

AR을 활용한 드론 교육훈련 게임 콘텐츠 설계

최창민(Chang-Min Choi) 한국엔터테인먼트산업학회 2021 한국엔터테인먼트산업학회 학술대회 논문집 Vol.2021 No.5

최근 드론 산업은 다양한 분야에 활용될 가능성이 제시되면서 급속히 확장되고 있다. 드론 시장 규모가 성장함에 따라 드론 관련 자격증에 대한 관심도 증가하는 추세이다. 하지만 현재 드론 관련 자격제도 및 교육체계가 미흡한 실정이다. 이에 본 연구에서는 드론 교육 훈련의 현실적인 어려움을 해결하고자 AR을 활용한 드론 교육 훈련 게임 콘텐츠를 설계 및 구현하였다. AR을 활용하여 드론 교육 훈련 게임 콘텐츠를 설계하는 것으로 환경적인 어려움을 해결함은 물론 플레이의 몰입감을 향상시켜 효과적인 드론 교육 훈련을 경험할 수 있을 것으로 기대한다. 향후 해당 콘텐츠를 통해 드론 자격 취득을 위한 드론 교육 훈련 게임 콘텐츠 설계 및 구현에 도움이 되고 나아가 드론 교육 훈련 게임 콘텐츠 개발의 방향성을 모색하여 보다 실용적이고 체계적인 드론 교육 훈련이 가능한 콘텐츠를 개발할 수 있을 것으로 기대한다. Recently, the drone industry is rapidly expanding as it is suggested that it will be used in various fields. As the size of the drone market grows, interest in drone-related certificates is also increasing. However, the current drone-related qualification system and education system are insufficient. Thus, in this study, drone education training game contents using AR were designed and implemented to solve the realistic difficulties of drone education training. It is expected that effective drone education training can be experienced by improving the immersion of play as well as solving environmental difficulties by designing drone education training game contents using AR. In the future, it is expected that the contents will help to design and implement drone education and training game contents for obtaining drone qualifications, and further explore the direction of development of drone education and training game contents to develop more practical and systematic drone education and training contents.

비수유기 유선염 및 유방농양 환자 증례 보고

최창민 ( Chang Min Choi ),이종덕 ( Jong Deok Lee ),유성원 ( Sung Won Ryu ) 대한한방부인과학회 2006 大韓韓方婦人科學會誌 Vol.19 No.2

피부과 방문 환자들의 피부 건강 및 피부 질환의 인식에 대한 분석

최창민 ( Chang Min Choi ),조희령 ( Hee Ryung Cho ),유박린 ( Bark Lynn Lew ),심우영 ( Woo Young Sim ),이준영 ( Jun Young Lee ),안규중 ( Kyu Joong Ahn ),송해준 ( Hae Jun Song ),김규한 ( Kyu Han Kim ),조광현 ( Kwang Hyun Cho ),이은소 대한피부과학회 2010 대한피부과학회지 Vol.48 No.3

Background: Social interests and the prevalence of skin disease have increased rapidly along with social development and improvement of life quality. Information on skin diseases and aesthetics are available through the internet and mass media. However, there have been few studies on the value of this information and the treatment-seeking behavior of patients. Objective: To evaluate the recognition of skin health and diseases in patients who visit dermatology clinics and to improve the role of dermatologists in the process. Methods: From March, 2008, to April, 2008, 1901 patients were asked to complete a questionnaire in 62 dermatologic hospitals. The questions covered: purposes of visiting the clinic; duration of skin disease; treatment-seeking behavior; recognition of the prescribed medicine; compliance and common sense about representative skin problems. Results: Patients visited the dermatologic clinic because of skin disease for 67.39% of patients, esthetic treatment in 22.88% of patients, and both in 9.73% of patients. For visits to a dermatology clinic for skin problems, 61.28% of patients visited a clinic but 38.72% did not. Most (81.38%) patients followed the doctor`s prescription. Most negative responses to prescribed medicine were due to the internet and mass media or wrong information from pharmacists (52.24%). Moreover, patients who learned about skin diseases and prescription medicines through the internet usually lacked compliance and common sense regarding their skin problems. Conclusion: The internet can provide good information about healthy skin and skin diseases, but we have to consider its disadvantages of exaggeration and misbelief. The effects of this tool have been overstated and excessively publicized in comparison to actual established clinical results. Use of the internet may delay diagnosis and decrease compliance. Consequently, dermatologists have to provide correct information to minimize the disadvantages of internet information. Patients who have abnormal skin problems should visit dermatologic clinics to be evaluated and treated appropriately. (Korean J Dermatol 2010;48(3):184~190)