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.

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.

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.

퇴행성 근골격계 만성 질환을 가진 독거노인 재활운동 관리 시스템

신기철(Shin ki chul),최정회(Choi jeong hoi),권재영(Kwon jae young),정근석(Jeong keun seok),최용균(Choi yong gyun),임현정(Lim hyun jeong),하나리(Ha nari),김지인(Kim jee in) 한국정보과학회 2019 한국정보과학회 학술발표논문집 Vol.2019 No.12

도시설계에서 문화유산 보전방법의 한 제안

신기철(Shin Ki-Cheol),허소영(Hur So-Yeong) 대한국토·도시계획학회 2001 國土計劃 Vol.36 No.3

This paper attempts to propose a practical method for conserving cultural inheritances; a method by which attributions of objects are systematically arranged and classified. Cultural inheritances have been those of established values of 'time', 'space', or 'norm' itself. That is why it is hard to deal with in the urban discourse or architectural practices. In treating this problem, and as an exploratory scheme, the Morphological Box Method, a typological method which F. Zwicky and other urban and architectural pupils thereafter had theorized earlier is adapted. Some cultural assets of the traditional walled city, Haw-Sung(old name of Soowon), are described as a case study. The objectives of this research are two-fold: first, it offers an arrangement framework to classify and inform of the data, for conservation purposes, of cultural inheritances that are scattered all throughout the country. Second, it will help to consider and apply the creative and diversified ways of conservation systematically.

多次元 都市空間設計 提案

申基哲(Shin Ki Chol),朴權一(Park Kweon-Il) 대한국토·도시계획학회 2000 國土計劃 Vol.35 No.4

It Is presupposed here that the future city centers will exhibit the physical structure of the 'spatial city' in which urban parts such as plots, streets, and buildings are interwoven together to form a three-dimensional whole. The propositions of this paper is divided into two parts. The first part deals with proposal for the urban renewal which closely connected with urban design, in order to exceed the limits of urban renewal in which spatial cities complex central urban area. And the second part deals with suggestion that Multi-dimensional Spatial Design is proposed in urban renewal, for accomplishing well-matched development on the district on the whole. This thesis defines the improvements of urban renewal. The first, to realize urban renewal project, there must be cooperations with urban design strategically, and the two systems should promote synergetic effects efficiently. Secondly, urban design should be a two-step-planning process that involves both the policy-making process and the execution-making process. Thirdly, urban design should plan phasing-developments gradually before the urban renewal project is commenced. And finally, urban design should use and develop private lands publicly, and strengthen incentive policies by utilizing transfer of development right(TDR).

空間都市建築의 方法

申基喆(Shin Ki-Cheol) 대한국토·도시계획학회 1998 國土計劃 Vol.33 No.5

Rational description is the point of departure for discourse and science : thus this study is aimed to suggest a method of describing complex urban design information in a rational manner. It is presupposed here that the future city centers will exhibit the physical structure of the ‘spatial city’ in which urban parts such as plots, streets, and buildings are interwoven together to form a three-dimensional whole, thus architecture become a small city, and vice versa. In such spatial cities, planners and urban designers must seek newer means to read, understand and control the complex central urban areas than those of today which regard the urban parts as separate entity. Thus the system of description of the urban design information(UDDS) proposed here is to be an alternative way to meet such demand in the future spatial cities. This paper consists of three parts : the first part deals with the definitions of key concepts and precedent efforts in the related vein ; and the second, the method of constructing the UDDS on the basis of the “Morphologica Box method” ; and the third part demonstrates an exemplary definition of the UDDS and some descriptions thereby. The eventual goal of the UDDS is to provide future urban professionals with new competence to communicate with and control urban design informations on the basis of the prospective network of urban information system ; it is however no more than an exploratory stepforth for this end, for practical application of the system must be preceded by further efforts of theorectical and practical verifications.

『三國史記』의 流隕 기록에 대한 재검토 - 雨鐵이 隕石이라는 관점을 중심으로 -

신기철(Shin, Ki-chul) 호서사학회 2022 역사와 담론 Vol.- No.101

이글에서는 『삼국사기』의 천변 기록 가운데 유성‧운석 기록들을 분류했던 앞선 연구 작업을 재검토한 후, 새롭게 유성‧운석에 관한 목록을 작성하고자 했다. 우선 유성과 운석을 포괄하는 流隕이란 용어가 『宋史』 「天文志」 流隕 편부터 사용되었음을 확인했고, 다음으로 이 유운이라는 항목으로 분류한 안영숙 등과 김일권의 분류 결과를 중국 문헌을 근거로 다시 분석하여 제외해야 할 기사와 포함할 기사를 새롭게 정리하였다. 이때 流星‧星墜‧星落‧星隕‧天狗가 들어간 기사들은 『사기』 「천관서」 등을 근거로 유운으로 분류하였다. 그러나 天有聲은 그 용례가 유운 이외에 지진과 기상 등에도 쓰였기 때문에 『삼국사기』에서 天有聲만을 근거로 한 백제 비류왕 22년(325) 기사와 신라 문성왕 10년(848) 기사를 유운 기록에서 제외했다. 그리고 중국 사서에서 볼 수 있는 혜성과 유성의 특징을 분석하여 헌덕왕 7년 기사를 혜성으로 판단하고 유운 목록에서 뺐다. 다음으로 고구려 보장왕 15년(656)의 ‘우철’을 기상 기록이 아닌 운석 기록으로 볼 수 있는지 살펴보았다. 먼저 시호테-알린 운석과 캄포 델 시엘로 운석 사례로 철질운석이 비처럼 내리는 것이 실제로 일어날 수 있는 일이라는 것을 확인했다. 이규경의 『五洲衍文長箋散稿』에서 우철을 별 혹은 운석과 관련지어 보았음을 확인했다. 중국 자료인 「楮記室」에서도 우철과 운석이 관련 있음을 확인했다. 이 용례가 7세기에도 같았는지 확인하기 위해 『通典』과 『太平寰宇記』를 살펴보았다. 여기에서 당 정관 21년(647)에 黠戛斯가 중국과 교류하기 시작했고, 이때 그들이 우철로 만든 질 좋은 도검을 가져왔음을 알았다. 그러나 후에 중국인들이 黠戛斯가 강한 비로 불순물이 제거된 철광석으로 도검을 만들었다고 생각하면서 이후로 우철에 관한 사건을 신기한 일 정도로 여겼다고 판단하였다. 이처럼 7세기부터 알려진 우철이란 용어는 계속 철질운석과 관련 있는 용어로 사용되었다. 이때 우철과 이것으로 만든 도검에 관한 이야기는 黠戛斯에서 중국, 돌궐 등으로 전해졌을 뿐만 아니라 고구려에도 알려졌을 것이다. 그러므로 『삼국사기』 기사처럼 철질운석이 떨어졌을 때, 고구려인들은 우철이란 용어를 사용하여 관련 사건을 기록하였을 것이다. 이러한 분석에 따라 우철을 운석으로 보고 유운 기록으로 판단하였다. I reexamined the existing works that categorized records related to the modern astronomical terms Yuseong(流星) and Unseok(隕石) in astronomical records of Samguksagi. First, I confirmed that the term Yuwun(流隕), which encompasses Yuseong and Unseok, was used from Yuwun part, which belongs to Astronomy(天文志) in Song History(宋史). Next, I re-analyzed the previous Yuwun studies based on Chinese literature and excluded two articles including Cheonyuseong(天有聲) and one article judged as a comet from the Yuwun list. And I wanted to examine whether Goguryeo"s "Ucheol(雨鐵)" article could be judged as Yuwun"s record, not a weather record. First of all, the examples of the Sikhote-Alin meteorite and the Campo del Cielo meteorite showed that falling like rain could actually happen. I confirmed that the term "Ucheo" expresses a similar phenomenon to these events in the domestic literature of the 19th century and the Chinese literature of the 14th century. I looked up "Tong Dian(通典)" and "Tai Ping Juan Yu Ji(太平寰宇記)" to see if these uses also expressed the same phenomenon in the 7th century. According to the books, Xiájiásī[黠戛斯] began to interact with China in 647, and the Chinese at this time thought that Xiájiásī[黠戛斯] made a quality sword Ucheol. Over time, however, the Chinese thought that Xiájiásī[黠戛斯] made a sword out of iron ore from which impurities were removed due to strong rain, and since then, they have dismissed the incident of Ucheol as mysterious. Like this, the word Ucheol known from the 7th century, was used as a term related to iron meteorites until the 19th century. For this reason, when iron meteorites fell, as stated in Samguksagi"s article, Goguryeo people used the term Ucheol to record related events. Based on this analysis, it was considered appropriate to judge the article about Ucheol as a record related to Yuwun.

중소기업 정책자금 지원사업의 비용-편익분석(Cost-Benefit Analysis)에 관한 연구

신기철 ( Ki Chul Shin ) 한국생산성학회 2013 生産性論集 Vol.27 No.2

The policy loan of the Small and Medium Enterprises is differentiated from private financial institutions in that it supports the SMEs in the area of market failure. Despite this differentiation, there is an tendency to find its efficiency and economic feasibility of the policy loan of the SMEs. The purpose of this study is to examine the economic feasibility of the policy loan of SMEs using a cost-benefit analysis of the financial programs for SMEs. The result of the analysis, which is expressed with benefit-cost ratio(BCR), is that the efficiency of the entire industry is 24.94 in 2008 and 19.66 in 2009. In addition to, the benefit-cost ratio(BCR) of manufacturing(13.57 in 2009) and non-manufacturing(22.23 in 2009) are also each high. In summary, the economic feasibility of the financial programs for SMEs is proved.