다중수신 수중음향통신을 위한 적응 시계열반전처리 기법의 이론연구와 실험적 검증

신기철,변양헌,김재수,Shin Kee-Cheol,Byun Yang-Hun,Kim Jea-Soo 한국음향학회 2006 韓國音響學會誌 Vol.25 No.5

Time-reversal processing (TRP) has been shown as an effective way to focus in both time and space. The temporal focusing properties have been used extensively in underwater acoustics communications. Recently. adaptive time-reversal processing (ATRP) was applied to the simultaneous multiple focusing in an ocean waveguide. In this study. multiple focusing with ATRP is extended to the underwater acoustic communication algorithm for multiple receiving locations. The developed algorithm is applied to the underwater acoustic communication to show, via simulation and real data, that the simultaneous self-equalization at multiple receiving locations is achieved. 시계열반전처리는 시간과 공간영역 동시에 집속을 수행할 수 있는 효과적인 방법으로 증명되어 왔으며, 시간영역에서의 집속 특성은 수중음향통신에서 광범위하게 이용되고 있다. 최근에는 해양도파관에서 동시 다중 집속이 적응 시계열 반전처리에 의해 구현되었다. 본 연구에서 적응 시계열반전처리에 의한 동시 다중 집속은 다중 수신을 위한 수중음향 통신 알고리즘으로 확장되며, 개발된 알고리즘은 수치실험과 실 데이터를 통해 다중 수신 위치에 동시에 자기등화가 가능함을 보였다.

콘카나발린을 이용한 단기간 건성안 동물 모델 유용성 연구

신기철,김형찬,고정화,위원량,이진학,김미금,Ki Cheul Shin,Hyung Chan Kim,Jung-Hwa Ko,Won Ryang Wee,Jin Hak Lee,Mee Kum Kim 대한안과학회 2007 대한안과학회지 Vol.48 No.5

Purpose: To evaluate the possibility of short-term dry eye model in rabbits by injection of concanavalin A (conA) to the lacrimal and haderian gland of rabbits. Methods: We injected conA (10 mg/ml, 0.05 ml) to the lacrimal and haderian gland of rabbits twice to induce inflammation of lacrimal gland and compared with saline-injected control by lacrimal gland biopsy with H&E staining for identification of inflammation. The ratio of lacrimal secretion was evaluated by Schirmer test (preinjection vs. postinjection of conA) for 10 days and the number of goblet cells was counted in 10 consecutive high power field using impression cytology with PAS staining. The corneal & conjunctival apoptotic cell deaths were investigated with TUNEL staining 10 days after injection. Results: Infiltration of inflammatory cells and destructed normal architecture of lacrimal gland was found only in conA injected group till 10 days. The Schirmer test showed marked reduction (0.56±0.26) by 5days after injection compared with control group (1.07±0.35) (p=0.02) and its significant difference was maintained till 10days. The number of goblet cell was 9.70±5.03/×200HPF, which was statistically significant decreased compared to control (47.50±17.13/×200HPF) at 10 days (p=0.00). Apoptotic cells were increased in injected eye (26.20±4.27) compared with those in control (16.60±2.70). Conclusions: Injection of conA to lacrimal glands in rabbit shows decrease of lacrimal secretion and similar cytological changes of the cornea and conjunctiva in human dry eye patients. It suggests its possible feasibility of short-term dry eye animal model for the 10 days.

높은 방향성 소음환경에서 DIFAR 수신센서 신호의 적응 빔형성에 의한 방위추정

신기철,김재수,Shin, Kee-Cheol,Kim, Jea-Soo 한국음향학회 2011 韓國音響學會誌 Vol.30 No.8

Conventional beamforming is ineffective in producing directional information in system with sparse degree of the freedom such as DIFAR (DIrectional Frequency Analysis and Recording) sonobuoy and in the presence of high directional noise. In this paper, Adaptive beamforming techniques are applied to produce directional spectra from a small number of sensors in highly directional noise environment. Conventional method as well as minimum variance and eigenvectors as adaptive method are evaluated via numerical test and real data. 높은 방향성 소음환경하에서 DIFAR (Directional Frequency Analysis and Recording) 소노부이 (sonobuoy)와 같이 채널의 자유도가 낮은 시스템에서 넓은 빔폭과 낮은 신호 대 잡음비를 갖는 일반 빔형성 기법을 이용하여 음원의 방위 정보를 획득하는 것은 비효율적이다. 본 논문에서는 높은 방향성 소음환경에서 DIFAR 수신센서와 같이 센서의 수가 극히 제한된 경우에 적응 빔형성 기법을 응용하여 적용성을 검증하였다. 일반 빔형성 기법과 적응 빔형성 기법들은 모의된 방향성 신호에 의해 비교 평가되었으며, 최종적으로 실 신호를 적용하여 성능을 검증하였다.

수동형 해양 시역전 수중음향장벽과 수중탐지에의 응용

신기철,김재수,Shin, Keecheol,Kim, Jeasoo 한국음향학회 2012 韓國音響學會誌 Vol.31 No.8

시역전 기술을 활용한 수중음향장벽에 의한 수중물체 탐지는 능동소나와 수동소나의 기법과 이론적 배경이 명확한 시역전 처리의 개념을 포함하고 있다. 본 논문에서는 수동형 해양 시역전에 의한 수중탐지의 개념과 이론을 수립하였다. 또한 수중음향 전파모델을 활용하여 모델링을 통해 수동형 시역전 수중음향장벽의 성능 예측을 수행하였다. 본 연구의 결과는 수동형 시역전 개념을 이용한 수중음향장벽 탐지시스템의 설계 시 유용한 성능예측 도구로 활용될 수 있다. Target detection by acoustic barrier method includes active and passive sonar technique and time reversal process whose theoretical background is already well defined. In this paper, the concept and theory of underwater detection by passive ocean time reversal is established. Also, the reason that this study was conducted was to investigate feasibility of complex mathematical modeling to provide some predictive capability for underwater acoustic barrier with passive time reversal. It may eventually lead to a useful predictive tool when designing underwater acoustic barrier detection system using the passive time reversal concept.

체육 교수 전문성의 검정을 위한 초등 임용고사의 개선 방안 탐색

신기철(Ki Cheol Shin) 한국스포츠교육학회 2006 한국스포츠교육학회지 Vol.13 No.4

Sump 증후군의 내시경적 치료에 대한 임상 경과

신기철 ( Ki Chul Shin ),이재현 ( Jae Hyun Lee ),장효식 ( Hyo Shik Chang ),송승호 ( Seung Ho Song ),남승우 ( Seung Woo Nam ),노임환 ( Im Hwan Roe ) 대한소화기학회 2003 대한소화기학회지 Vol.41 No.3

Background/Aims: Endoscopic management has been the first choice of treatment for sump syndrome. This study was performed to analyze the outcome of endoscopic treatment for sump syndrome. Methods: We retrospectively reviewed 21 cases of sump syndrome diagnosed by ERCP from April 1994 to July 2000. Results: The symptoms of 21 cases with sump syndrome were cholangitis in 61.9% (13 cases), abdominal pain in 28.6% (6 cases), and indigestion in 9.5% (2 cases). The mean clinical latency of sump syndrome was 5 years 8 months (22 months to 15 years) after surgery. Cholangiogram showed 12 cases of food debris, 7 cases of stones or stone debris, 2 cases of food debris with stones. All cases were treated successfully with antibiotics and endoscopic foreign body removals. The recurrence rate after the endoscopic therapy was 4 cases (19%), which were also treated repeatedly by endoscopic interventions. Conclusions: Sump syndrome can be successfully treated endoscopically, and the repeated endoscopic treatment can be a highly recommendable choice even for patients with recurrent sump syndrome. (Korean J Gastroenterol 2003;41:219-223)

스포츠교육학의 교육적 역할과 학문적 과제

신기철(Ki Cheol Shin) 한국스포츠교육학회 2011 한국스포츠교육학회지 Vol.18 No.4

스포츠교육학은 체육학의 분과 학문 분야로 인정받고 있으며, 교육 현장의 개선에도 많은 기여를 해 오고 있는 것으로 평가된다. 이제 스포츠교육학은 학교체육뿐만 아니라 생활체육과 전문체육 분야에까지 연구 영역이 급속도로 확장되고 있다. 이러한 가운데 선진 외국에서는 스포츠교육학의 연구 동향을 지속적으로 살펴봄 으로써 연구 성과에 대한 반성과 함께 새로운 연구 방향을 모색하고 있다. 최근에 우리나라에서도 스포츠교육학의 연구 동향에 대한 연구가 진행됨으로써 스포츠교육학의 학문 체계가 정교화 되고 있다. 그러나 이와 같이 학문적 성과에 대한 반성은 상대적으로 잘 이루어지고 있는 반면에 스포츠교육학이 실제 현장에서 어떠한 내용과 방법으로 적용되고 있는지에 대한 검토와 반성은 거의 이루어지지 않았다. 따라서 본 글에서는 연구자가 전공한 스포츠교육학을 교사교육 프로그램에 적용하여 실천한 사례를 통해서 스포츠교육학이라는 학문이 예비교사교육에 어떠한 내용과 방법으로 제시되어야 하는지, 그리고 이와 같은 역할이 보다 더 세밀하고 체계적으로 수행될 수 있기 위해서 요구되는 학문적 역할에 대해서 논의를 하였다. 초등 예비교사들에게는 무엇보다도 체육교육에 대한 비전을 심어주는 것이 중요했으며, 체육교육을 위한 미션을 인지하고 수행하도록 하는 것이 필요하였다. 또한 스포츠교육학을 교사교육에 적용하는 맥락에서 스포츠교육학은 종합·응용 학문으로서의 역할이 강화되어야 하고, 현장 실천 중심의 연구를 활성화하여야 하며, 특별히 바람직한초등 체육 교사상을 정립해 나가야 한다는 학문적 과제를 제안하였다. Sport pedagogy is regarded as the core sub-area of kinesiology, and is judged to be a help for improving practical physical education. Now sport pedagogy is rapidly expanding from school physical education to club sport education and elite sport education. In this context advanced countries have tried to seek the new research direction through reviewing the current research trends of sport pedagogy. Recently the researches that review the research trends have been conducted, so that the academic hierarchy of sport pedagogy can be delicate. Although the academic achievements were relatively reflected well, but the practical contributions of sport pedagogy in related areas were hardly reflected. Therefore the purpose of this paper is to discuss not only what is the educational role of sport pedagogy, but also what is the academic tasks of sport pedagogy through the researcher`s case of teaching pre-service teachers the course of physical education. It is very important to let elementary pre-service teachers have vision of teaching physical education, and make them recognize and do the mission of teaching physical education. And sport pedagogy should be the all-around and applied study, conduct the site-based research, and establish the desirable teacher character.

21 Helicobacter pylori에 대한 버섯의 생장억제 효과

신기철 ( Ki Chul Shin ),노임환 ( Im Hwan Roe ),남승우 ( Seong Woo Nam ),신지현 ( Ji Hyun Shin ) 대한소화기학회 2002 대한소화기학회 추계학술대회 Vol.2002 No.-

전신성 홍반성 루푸스와 연관된 악성림프종 3예

신기철 ( Ki Chul Shin ),이윤종 ( Yun Jong Lee ),최영주 ( Young Ju Choi ),강성욱 ( Seong Wook Kang ),이은봉 ( Eun Bong Lee ),방영주 ( Yung Jue Bang ),송영욱 ( Yeong Wook Song ) 대한류마티스학회 1999 대한류마티스학회지 Vol.6 No.4

The coexistence of autoimmune and lymphoproliferative disorders has rarely been reported. We report 3 cases of malignant lymphoma associated with systemic lupus erythematosus(SLE). In one case, Hodgkin`s disease and SLE occurred simultaneously. In the other 2 cases, non-Hodgkin`s lymphoma occurred prior to and after development of lupus, respectively. The clinical courses of the patients are described with review of the literature.

안와 근염

신기철 ( Ki Chul Shin ),한창완 ( Chang Wan Han ),임용성 ( Yong Seong Lim ),송영욱 ( Yeong Wook Song ) 대한류마티스학회 1998 대한류마티스학회지 Vol.5 No.2

Orbtial myositis is an idiopathic, nonspecific inflammation of primarily one or more extraocular muscles and is considered as a subgroup of orbital pseudotumor. It can be distinguished as acute, subacute or chronic form. Acute orbital myositis is a single episode of orbital pain without fever lasting less than 6 weeks, whereas subacute or chronic form is a persistent episode lasting more than 2 months or with recurrence. The diagnosis is made by CT scan, ultrasonography or MRI, which is characterized by enlargement of extraocular muscle bellies and tendons. Although spontaneous resolution may be anticipated within 3 to 6 weeks, good treatment response is shown with corticosteroids. We recently experienced a case of orbital myositis in a 50 year-old female. She had bilateral orbital swelling 1 year prior to admission. Orbital swelling was relieved gradually but relapsed to show limitations of extraocular muscle movement. In orbit CT scan, there was diffuse thickening of eyeball muscle and swelling of facial subcutis. She was treated with methylprednisolone with marked clinical improvement after 4 days. After 1 month period of corticosteroid treatment, she had residual limitation of upward eyeball movement. We present this case with literature reviews.