Efficient organic tandem solar cell with Rb₂CO₃/IZO and Cs₂CO₃/IZO interlayer

이봉준,김효정,김장주 한국고분자학회 2008 한국고분자학회 학술대회 연구논문 초록집 Vol.33 No.2

날개끝 형상에 따른 항력감소 연구

이봉준,이경준,신동진 한국항공우주학회 1989 한국항공우주학회 학술발표회 논문집 Vol.- No.-

태안반도 산촌형성요인에 관한연구

이봉준 서울대학교 지리교육과 1977 지리학과 지리교육 Vol.7 No.1

The aim of this study is to clarify regional characteristics by examining various factors having developed dispersed pattern of settlements on the Tae-An Peninsula, Choong Cheung Province. For the purpose of this study, intensive bibliographical studies of data concerned with this area were done and used actual field work. Results of this study may be summarized: (1) Tae-An peninsular, which belongs to Choongcheung Nam-Do and is bordered with the Gyeon gi Bay, has not been closely connected with the central area of the Gyeunggi Province for a long time. About 79% of the peninsula is made up of low mountains and hills. Plains and rivers are poorly developed, arable lands do not extend continuously in the peninsula. Ground water level is comparatively high and the entire land is well-drained. These physical characteristics supply foundations for the development of dispersed settlements. (2) Tae-An peninsular is one of places which have long been inhabited by men. For .a long time in its history, this peninsula was quite important for water transportation. In particular, in the Koryo and the Yi-Dynasties it was considered as a place of much importance on account of its water transportation of taxation rice. There were in this peninsula two attempts of constructing a canal accross it. (3) To defend the peninsula from the invasions of the Japanese pirate raiders and preserve human lives and properties, the inhabitants of this peninsula formed military villages and other villages surrounded with walls. At the end of the Koryo Dynasty, however, frequent invasions of the Japanese raiders forced the villagers to move to some .other places. The settlements which had been developed in the pre-historical era was since then devastated. (4) At the beginning of the Yi Dynasty these settlements were redeveloped. Since the majority of the villagers originally inhabited in this peninsula had moved to other regions, others who came into this peninsula formed new settlements. In addition to the common men who moved to this peninsula many noble men rusticated here from Seoul. These flows of population caused the number of population in this peninsula to increase with the result of maintaining. the lineage of the family. (5) It is estimated that tie dispersed villages of this peninsula were generally formed in the early Yi Dynasty. The villagers were for the most part composed of rusticated people and others flowed into this peninsula and villages had comparatively broad arable lands. These dispersed villages still remain almost as they were in the past. As suggested above, the development of these dispersed villages was not due to one single. factor, but to various factors such as the physical features, population outflows and inflows, the mode of choosing places for inhabitation in accordance with the theory of Poong-Soo, the relationship between the nobility and the common people, and tenant farming. These dispersed villages involve some factors which may interfere with the New Country Movement. For example, the difficulty incooperation between or among villages and in suppling electricity to all the villages. Besides, this peninsula is geographically vulnerable to the North Korean invasion: This is why the Government intends to bring together the small villages into larger ones. It is expected therefore that the traditionally dispersed villages in this peninsula will be grouped in the near future.

지반정보로부터 3차원 가시화 프로그램 개발에 관한 연구

이봉준,민홍,고훈준 한국지리정보학회 2022 한국지리정보학회지 Vol.25 No.4

시추데이터는 작업자가 작업현장에서 안전하게 공사를 수행할 수 있도록 제공하는 지반정보로, 현재 시추데이터를 3차원 데이터로 만들어서 3차원 형태의 이미지로 볼 수 있도록 지원하고 있다. 지반정보의 3차원 가시화를 이용하여 다양한 프로그램을 개발하는 국내의 기업들은 지반 정보의3차원 가시화를 위해 C Tech Development Corporation에서 개발한 MVS 프로그램을 사용하고있다. 그러나 MVS 프로그램은 유료 프로그램이고 국내에서 개발하는 3차원 관련 프로그램에서사용하기에는 어려움이 있다. 본 논문에서는 파이썬의 Gempy 오프 소스를 이용하여 군집화된 시추정보로 부터 3차원 지층모델을 생성할 수 있도록 MVS를 대체할 수 있는 라이브러리를 개발하고자 한다. 3차원 지층모델 프로그램은 각 지층별 포인트 데이터를 생성하고 보간을 통해서 지층별 표면을 생성한다. 그리고 각 지층별 표면을 합하여 3차원 지층모델 프로그램을 완성한다. 고양지역의 시추데이터로부터 MVS 프로그램과 제안하는 프로그램으로 3차원 모형을 생성하여 비교하였을 때 큰 차이가 없음을 확인하였다.

지하공간통합지도 관리 시스템의 효율적인 운영을 위한 공간 데이터 갱신 방법

이봉준,고훈준 대한산업경영학회 2022 산업융합연구 Vol.20 No.7

지하공간에는 다양한 구조물들이 있고 그 구조물들의 지하공간 데이터는 지하공간통합지도 관리 시스템(IUGMMS)에서 3D 데이터로 관리되고 있다. 작업자는 준공도서 제출 프로그램으로 변경된 지하공간 데이터를 반영한 통합지도 전체를 IUGMMS에 전송하여 갱신하고 있다. 그러나 통합지도 파일의 크기가 크기 때문에 전송하고 갱신하는 시간이 지연되는 문제점이 있다. 본 논문에서는 변경된 통합지도와 IUGMMS에 저장되어 있는 통합지도에서 공간특성정보를 각각 구하고 비교해서 변경된 지하정보 데이터가 있는 통합지도만 추출하여 전송하고자 한다. 실험 결과, 기존 방법은 전송하려는 통합지도의 영역이 넓을수록 통합지도를 전송하는 시간과 갱신하는 시간이 파일 크기에 비례하여 증가하였지만, 제안한 방법은 변경된 지하공간 데이터가 포함된 통합지도만 전송하기 때문에 전송 시간이 짧았고 갱신하는 시간도 짧았다. 그 결과 변경된 통합지도를 전송하고 갱신할 때 발생하는 시간의 지연을 줄일 수 있었다.

水平꼬리날개의 操舵方式과 操縱力에 對한 解析

李奉俊 한국항공대학교 1971 論文集 Vol.3 No.-

水平꼬리날개의 操航方式을 區分하면 水平安定板(horizontal stabilizer)과 昇降 키(elevator)를 分離해서 組合한 普通方式의 것과 水平꼬리날개 全體가 可動式으로 되여 stabilizer와 elevator의 役割을 同時에 하는 stabilator로 區分된다. stabilator는 操縱效率이 좋아서 어떤 자세에 處하든지 間에 失速하지 않은 利點이 있으나 反面 control stick을 自由로 했을때 安定性이 좋지 않으므로 經飛行機에서는 이를 잘 使用하지 않았다. 그러나 anti-servo tab 裝置를 使用하면 이를 解決할 수가 있고 低速, 經飛行機에서도 滿足할만한 性能을 얻을 수 있다. 本論文에서는 水平꼬리날개의 操航方式과 stabilator의 特性을 解析하고 操縱力을 求하였다. Horizontal tails are of two basic types, the flapped type which is a conventional tail that forms an elevator as a part of a fixed stabilizer, and the stabilator type which is one piece moving tail that performs the functions of the stabilizer and elevator. These stabilator types have an advantage of being always operated in an unstalled condition, regardless of airplane attitude by its highest control surface effectiveness. For the smaller, low-speed airplane, stabilator control surfaces will be satisfactory for horizontal tail surfaces. In this paper, several discussions were made about the relationship between the characteristics and control forces of the all moving tail and conventional flapped horizontal tail control surfaces.

낮은 레이놀즈수에서 三角 윙�꼭�있는 날개의 特性

李奉俊 한국항공대학교 1987 論文集 Vol.25 No.-

Three dimensional wing produces an induced drag. Many studies have been made to reduce the induced drag and to increase the lift-drag ratio by properly controlling the vortex at a wing tip. It has been reported that the device, such as delta winglet, which is small, cambered and delta shaped wing like surface are remarkably effective for reducing the induced drag of a wing. A wind tunnel investigation has been conducted to determine the effect of delta winglet on the lift and drag characteristics of an aspect ratio 5 wing, wortmann FX-63-137 airfoil, unswept wing at low Reynolds numbers of 200,000. The results indicate that the delta winglet provided the basic wing with an increase in the lift curve slope, a reduction in the induced drag, and an increase in lift-drag ratio.

低速 Airfoil에서 境界層에 依한 功力係數의 變化에 關한 硏究

李奉俊 한국항공대학교 1975 論文集 Vol.8 No.-

Mach 數가 작은 Airfoil에서 境界層에 의한 空力係數의 變化를 다음과 같이 5단계로 구분하여 계산하였다. 1)層流境界層을 Thwaite 方法에 依해서 計算했고 2)Schlichting & Ulrich 曲線에 依해서 lower critical 點을 推定하고 3)Schlichting 곡선에 依한 遷移漸의 예측 4)Head 의 方法에 依한 亂流境界層의 計算 5)Squire 와 Young 의 關係式에 依한 Wake 의 計算을 하므로서 境界層에 依한 空力係數의 變化를 구하였다. 本 論文에서 Airfoil의 空力係數를 計算하기 爲하여 遷移點의 결정에 앞서 lower critical point를 먼저 구하였다. 뒤에 理論値와 實驗置를 비교하기 爲하여 NACA 23012 Airfoil의 수직空力成分을 여러가지 맏음각에 對하여 구하고 實驗置와 比較하였다. A method for calculating the aerodynamic coefficient of airfoils at low Mach number is studied. Study is based on 1)calculation of lamiar boundary layer by Thwite's method 2)prediction of lower critical point by Schlichtint & Ulrich curve 3)prediction of transition point by Schlichting curve 4)calculation of turbulent boundary layer by Head's method and 5)calculation of wake by means of the Squire & Young relation. In this study the prediction of lower critical point was done first, then predicts transition point for calculating the aerodynamic coefficient. Normal aerodynamic component has been calculated by this method for NACA 23012 airfoil at various angle of attack. Comparison of the results wkth NACA experimental data shows a good agreement.

S.T.O.L機에 利用되는 吸入에 依한 境界層의 制御特性

李奉俊 한국항공대학교 1976 論文集 Vol.9 No.-

高場力裝置를 要하는 航空機 즉 STOL機에나 其他 高場力을 發生시켜주는 方法中에는 Slat와 境界層吸入에 依한 層流흐름制御方式을 많이 使用한다. 特히 旣存 經航空機를 STOL機로 改造할 必要가 있을때는 이들 境界層制御方法을 使用하여 c?를 높이는 것이 效率的이고 經濟的이란 것이 ?明되고 있다. 本 論文에서는 이중 境界層吸入에 依한 方法을 理論的으로 考察하고 最近 NAL에서 發表된 FA200XSTOL機의 實驗資料를 比較檢討하였다. 그 結果 ?c?이 增加하는 面에서 서로 一致하는 傾向을 보였다. The boundary layer control system using distributed area suction located on the leading edges of flaps and ailerons, as well as a full span slat is utilized as the high lift devices on the STOL type airplane. To modify the conventional light airplane to the STOL type airplane, the boundary layer control system must be provided to inrease in C? Suction removal of the boundary layer is studied by theoretical method on this paper and compare with the experimental data of the FA200X airplane developed in NAL to investigate the operational problems of STOL type airplane. Comparison of the result in increasing ?C? shows a good agreement each other.

初等學校 施設·設備 改善에 關한 硏究

李鳳濬 韓國實科敎育硏究學會 1997 實科敎育硏究 Vol.3 No.1

Since the school facilities which support the student learning such as the library, audiovisual room, etc. are characterized with a characteristic of common use in the aspect that total students or school staff use them in common, and such facilities play even as a place where guidance in life and useful information can be acquired and exchanged other than the activities related the curriculum, they should be so arranged that it is proper and functional for the students to perform activities and learn something there. Instead, it is a reality that such important facilities and equipments lack and are poor, and regardless of the user's demand of education, they take spaces in schools and are arranged disorderly. Therefore, this study was motivated from the necessity for the effect of education by the school's facilities and equipments to be uplifted.