Interactive Space Launch Design Framework Development using Centralized Database Architecture

Thawdar Lwin(토우다 린),Jung-Il Shu(서정일),Jin-Wook Kim(김진욱),Jae-Woo Lee(이재우),Sangho Kim(김상호) 한국추진공학회 2014 한국추진공학회 학술대회논문집 Vol.2014 No.12

This study describes a design framework development using system engineering and centralized database concepts for various space launch vehicles to assist aeronautical engineers during mission and conceptual design and analysis process. This framework was first implemented in Matlab environment. Then due to some technical insufficiencies it is upgraded to a better version in VB.Net environment. Centralized database concept is applied for better data storage efficiency for all input and output of modules in the framework. Moreover, sorting function for database of competitive rockets over the world is added in the process for requirements. The purpose of utilization of data mining is to make the design optimization performed with fast and successful convergence by predicting the data necessary for the design optimization. Finally, the information resulted from a mission design is utilized as the system baseline to a newly introduced stage ‘Conceptual Design’. The framework GUI design is done mainly based on system engineering concept, thereby allowing user to interact with GUIs to easily finish the whole mission design process from start to end. The design framework is developed in a high-level technical computing language and interactive environment of VB.Net and 3D modeling using CATIA v5. To sum it up, this design framework includes and integrates many different functions and newly-added features: data mining for estimation and optimization of required initial values, fast accessibility to data mining values once it is determined, design analysis, design synthesis, and geometric 3D modeling of final configuration of the designed space launch vehicle. With this space launch framework, the mission and conceptual design for the rocket system targeted on the 700 x 700 ㎞ circular orbit has been successfully developed and demonstrated the efficiency of the framework.

우주 발사체 3차원 궤적 최적화 및 프레임워크 개발

조성준(Seong-jun cho),서정일(Jung-il Shu),Aye Aye Maw,이재우(Jae-Woo Lee),김상호(Sangho Kim) 한국추진공학회 2015 한국추진공학회 학술대회논문집 Vol.2015 No.5

본 연구에서는 우주 발사체 시스템 설계를 위한 3차원 궤적 최적화를 수행하고 프레임워크를 개발하였다. 궤적 프로그램은 중량, 추진, 형상정보를 바탕으로 공력해석, 대기환경 해석, 받음각·옆미끄러짐각 설계, 운동방정식 등 각 모듈의 해석을 토대로 최적화를 진행하였다. 설계변수는 킥턴, 중력턴, 받음각, 옆미끄럼각 등을 고려하였다. 코드는 동력 비행구간과 자유 비행구간을 고려한 설계가 가능하며, 발사체 임무 비행 중 스티어링 손실, 압력 손실, 지구 자전에 의한 손실, 항력 손실, 페어링 분리에 의한 속도 이득 또한 계산 될 수 있도록 구성하였다. 최적화 문제 정식화는 목적함수로써 페이로드 최대화와 발사체 진입 종말속도 최대화로 두 가지 문제를 구성하였다. 코드는 포트란을 기반으로 구성하였으며, 최적화 기법은 SQP(Sequential Quadratic Programming)가 사용되었다. 프레임워크는 비주얼 베이직을 통해 사용자가 쉽고 빠르게 해석하고 결과를 볼 수 있도록 개발되었다. 코드 검증을 위해서 고도 700km, 탑재중량 1500Kg을 목표로 하는 한국형발사체(KSLV-II)를 토대로 값을 도출하였으며 성공적으로 임무를 수행함을 확인하였다.

임무설계 유기성을 고려한 우주발사체 개념설계 프로세스 및 프레임워크 개발

김진욱(Jin-Wook Kim),Thawdar Lwin,서정일(Jung-Il Shu),이재우(Jae-Woo Lee),김상호(Sangho Kim) 한국추진공학회 2015 한국추진공학회 학술대회논문집 Vol.2015 No.5

본 연구에서는 우주발사체 임무설계를 통해 도출되는 사이징 및 임무 해석 결과를 이용하여 발사체 세부 형상, 세부계통 해석 결과 등을 도출하는 개념설계 단계까지의 설계 프로세스 및 프레임워크를 개발하였다. 임무설계 단계에서는 주어진 목표 궤도 및 탑재체 질량에 맞춰 임무를 수행할 수 있도록 사이징을 진행하며, 개념설계 단계에서는 사이징 및 임무 해석 결과를 이용하여 추진, 공력, 구조하중 등의 세부계통 해석을 진행한다. 또한, 개념설계 결과를 통해 도출된 추진 정보 및 질량 정보는 다시 임무설계로 피드백 되어 사이징 및 임무 해석을 진행하도록 임무설계와 개념설계 간의 유기성을 고려한 우주발사체 설계 프로세스를 개발하였다. 그리고 이 모든 설계과정을 VB.NET으로 GUI화하여 프레임워크를 개발하였으며, SQLite 데이터베이스 프로그램을 이용하여 입출력 값을 저장하고 관리한다. 마지막으로 KSLV-II 제원을 이용하여 결과를 도출하고 검증을 진행하였다. In this study, our integrated design process and framework for space launch vehicles (SLV) was developed. The established design process consisted of the ‘Requirement Analysis’, ‘Mission Design’, and ‘Conceptual Design’ stages. In the ‘Mission Design’ stage, the mission and sizing results are obtained. The ‘Conceptual Design’ stage contains several analysis module: the Propulsion, Aerodynamics, Load & Structure, and Weight. These stages implement the system engineering process, and each stage exchanges information interactively. And the framework for SLV design is developed based on the VB.Net. The whole data of input and output are saved in SQLite which is database program. The results of design are obtained using KSLV-II specification and the validation is performed.

論文(논문) : 통합 해석 및 설계 최적화 기술을 이용한 무인기 성능 향상 연구

김지민 ( Ji Min Kim ),누엔반 ( Nhu Van Nguyen ),서정일 ( Jung Il Shu ),티안막심 ( Ma Xim Tyan ),이재우 ( Jae Woo Lee ),김상호 ( Sang Ho Kim ) 한국항공운항학회 2013 한국항공운항학회지 Vol.21 No.1

This paper describes the design optimization of Unmanned Aerial Vehicles(UAVs). An optimization framework has been developed and implemented for the conceptual design of UAVs. An integrated design analysis program was developed with several analysis modules such as propulsion, performance, mission, weight, and stability and control. A UAV configuration design optimization was performed by implementing the integrated analysis to enhance the endurance of UAVs. A SQP optimizer was utilized to build an optimization module for this program and sensitivity analysis was performed to determine the trends of shape variables for developing optimization objective. In conclusion, the results indicate that the resulting optimized UAVs configurations show performance improvements over the baseline design and reliable analysis results.

全羅北道 中學生의 英語學力差 및 英語敎師 構成上의 諸問題

嚴定沃,徐正一 圓光大學校 1976 論文集 Vol.10 No.-

1. After we had tested with the paper test in order to see the English achievement of the middle school students in Jun Buk province, we had the following results. 1) The difference of English achievement in the defferent regions. (1) The difference of English achievement between the city and the town is not deep (2) The difference of English achievement the city and country is considerably deep. (3) The record distribution of the city is normal. (4) The record distribution of the town is not so different as the city. (5) As the recofd distribution of the country is descending tendency, it is a matter of grave concern. 2) The difference of English achievement between the public school and the private school. (1) There is no difference between the public school and the private school in the city. (2) There is some difference in the town. (3) There is considerable difference in the country 3) The difference of English achievement between the differnt sex. (1) The ablility of the boy students is superior to the girl sutdents. 4) In the improvement (1) It needs the support of education authorities in order to diminish the difference of Englisch achievement between the city and the country. (2) It needs to intensify the teacher's re-training and to introduce thenew teaching methods into his class. (3) It needs to supplement the country school's facilities. (4) The writer proposes the teacher's capacity institution. (5) It needs to abolish the present appointment system for teacher and to be transferred to the state examination. (6) The education authorities must try to level the schools in order to diminish the difference of achievement between the public school and the private school. 2. After we had investigated the various problems of teachers' formation in Jun Buk province, we had the following results. 1) In the contentment of teaching profession. (1) Teachers are proud of their teaching profession as an English teacher, especially the school mistresses are high in their pride. (2) The teaching profession is the hard speciality. (3) They can endure the social treatment and the reward for them. (4) As they think the teaching profession is not prospective, they don't want recommend it for their childern if they should not have any special talent for education. 2) The relation between the public school teachers and the private school teacher. (1) The public school is better than the private school in teacher's reward. (2) The private shcool teachers want to transfer to the public school as possible as they can. (3) The writer agrees with the sate examination for teacher of eduacation authorities. (4) The teachers do not agree with the present examination system for high school in 5 big cities and want to compete each other. 3) In the improvement, (1) We must establish the social mood which thinks the teaching procession important for teacher's morale. (2) There must be a balance in the teacher's reward between the public school and the private school in order to get the efficient level of education. (3) We had better give the graduate of the teacher's college the priority for considerable periods in teacher's appointment. (4) When the teahcer get the higher qualification, the living English must be added with the required subject. (5) In the point of English teacher's re-training, the graduate course of education must be established in each university in Jun Buk Province.