공리적 설계를 이용한 비대칭 내부 짐벌을 가진 진동형 자이로스코프의 강건설계

박경진,황광현,이권희,이병렬,조용철,이석한,Park, Gyeong-Jin,Hwang, Gwang-Hyeon,Lee, Gwon-Hui,Lee, Byeong-Ryeol,Jo, Yong-Cheol,Lee, Seok-Han 대한기계학회 2002 大韓機械學會論文集A Vol.26 No.5

Recently, there has been considerable interest in micro gyroscopes made of silicon chips. It can be applied to many micro-electro-mechanical systems (MEMS): devices for stabilization, general rate control, directional pointing, autopilot systems, and missile control. This paper shows how the mechanical design of the gyroscope can be done using axiomatic design, followed by the application of the Taguchi robust design method to determine the dimensions of the parts so as to accommodate the dimensional variations introduced during manufacturing. Functional requirements are defined twofold. One is that the natural frequencies should have fixed values, and the other is that the system should be robust to large tolerances. According to the Independence Axiom, design parameters are classified into a few groups. Then, the detailed design process is performed fellowing the sequence indicated by the design matrix. The dimensions of the structure are determined to have constant values fur the difference of frequencies without consideration of the tolerances. It is noted that the Taguchi concept is utilized as a unit process of the entire axiomatic approach.

철도치안 확보방안 연구

박경진(Park Gyeong Jin) 한국공안행정학회 2015 한국공안행정학회보 Vol.24 No.1

The purpose of this study was to ensure comfortable and safe railroad journey for people who use railroad transportation by considering the matter to secure railroad security in trains according to of development railroad industry and the change of working environment railroad police, and by presenting an efficient plan of improvement to solve the railroad security problem. Recently the environment of railroad industry has been rapidly changed ; opening of KTX, expansion of national railroad network, construction of privately invested station building. Expansion of consumer-oriented railroad service led to increase of passengers. However, railroad policy is inclined to convenience, holding off the railroad security, the safety, without any proper measures. The expansion of the line of duty of railroad policy, the agency in full charge of railroad security, and the introduction of new subject of railroad crime on railroad facilities are the factors that trouble operation of personnel that is, railroad police, and make the railroad security insufficient. Necessary are, in the short term, practical education of Korail train crew and publicity of intra-train crime report app to improve prompt counter-crisis ability in case of crime ocurring in the train and in mid- and long-term, increase of personnel to install security check system within the station, strengthening intra-train crime prevention through efficiency of human resources by adjusting the jurisdiction of criminal investigation and establishment of unified train crime investigation center(CIC) and intra-train report system network. 본 연구는 철도산업의 발전과 철도경찰의 직무환경변화에 따른 열차 내 철도치안 확보의 문제점을 검토하고, 열차 내 철도치안 문제 해결을 위한 효율적인 개선방안을 제시함으로써 철도교통을 이용하는 국민들이 편안하고 안전한 철도여행이 될 수 있도록 하는데 목적이 있다. KTX 개통, 국가 철도망 확대, 민자역사의 신축 등으로 수요자 중심의 철도서비스 확대와 여객의 증가로 인해 국내 철도산업 환경은 급변하고 있다. 그러나 이제까지의 철도정책이 편의성에만 집중되고 안전성인 철도치안 문제는 뒷전으로 미루어져 적절한 대책이 이루어지지 않고 있다. 철도치안 전담기구인 철도경찰의 직무범위 확대, 철도시설 내의 새로운 철도범죄 주체의 유입은 철도경찰의 인력운용을 어렵게 만드는 요인으로 열차 내 철도치안 확보에 미흡한 요인이 되고 있다. 본 논문에서는 이에 대한 대책을 다음과 같이 제시하고자 한다. 첫째, 단기적으로는 열차 내 사건 발생 시 신속한 위기 대응 능력 향상을 위한 한국철도공사 열차승무원의 실질적인 교육, 열차 내 철도범죄 신고 모바일앱 홍보 등을 들 수 있다. 다음으로, 중 · 장기적으로는 철도역사 내 보안검색시스템 설치를 위한 인력 증원, 수사관할권 조정으로 인력 효율화를 통한 열차 내 방범활동 강화 및 철도범죄통합수사센터(CIC)와 열차 내 신고체계 네트워크 구축이 필요하다.

상황인식 기반의 신뢰성 있는 u-Health 시스템

박경진 ( Gyeong-jin Park ),김경태 ( Gyeong-tae Kim ),최우혁 ( Woo-hyeok Choi ),김우성 ( Woo-sung Kim ) 한국정보처리학회 2012 한국정보처리학회 학술대회논문집 Vol.19 No.1

오늘날의 정보통신 환경은 유비쿼터스 IT기술의 시대로 진입하고 있다. 유비쿼터스는 사용자가 컴퓨터나 네트워크를 의식하지 않은 상태에서 시간과 장소에 구애받지 않고 자유롭게 네트워크에 접속 할 수 있는 정보와 환경을 의미한다. u-Health(Ubiquitous-Health)는 의료 및 국민 복지에서 떠오르는 분야이며 기존의 의료서비스와는 달리 사용자가 간편하고 언제 어디서나 사용될 수 있는 시스템이다. 기존 u-Health 시스템은 사용자가 착용한 센서로부터 신체 데이터를 제공받고, 제공 받은 데이터로 사용자가 현재 어떠한 상태인지를 파악한다. 그러나 센서로부터 제공받은 신체데이터는 무선통신으로 인한 데이터의 손실 및 오류가 발생하게 된다. 이러한 단점을 극복하고 정확한 환자의 상태를 판단하기 위한 방법으로 온톨로지 기반의 상황인식을 적용하여 기존의 u-Health 시스템 보다 더욱 신뢰성 있는 u-Health 시스템을 구축하고자 한다.

등제한조건 함수를 이용한 구조물의 호몰로지 설계

이권희,박경진,Lee, Gwon-Hui,Park, Gyeong-Jin 대한기계학회 1996 大韓機械學會論文集A Vol.20 No.3

The concept of homology design has been devised for the application to large telescope structure by S.v.Hoerner. It is defined that the deformation of a structure shall be called homologous, if a given geometrical relation holds, for a given number of structural points, before, during, and after the deformation. Recently, the need of homology design in the structural design has been increase due to the required precision in the structure. Some researchers have utilized the theory on the structural design with finite element method in the late 1980s In the present investigation, a simple method using geometrical equality constraints is suggested to gain homologous deformation. The previous method is improved in that the decomposition of FEM eqation, which is very expensive, is not necessary. The basic formulations of the homology design with the optimization concept are described and several practical examples are solved to verify the usefulness and validity. Especially, a back-up structure of a satellite antenna is designed by the suggested method. The results are compared with those of existing researches.

매 시간단계의 등가정하중을 다중하중조건으로 이용한 준정적 구조최적화 방법

최우석,박경진,Choe, U-Seok,Park, Gyeong-Jin 대한기계학회 2000 大韓機械學會論文集A Vol.24 No.10

This paper presents a quasi-static optimization technique for elastic structures under dynamic loads. An equivalent static load (ESL) set is defined as a static load set which generates the same displacement field as that from a dynamic load at a certain time. Multiple ESL sets calculated at every time step are employed to represent the various states of the structure under the dynamic load. They can cover every critical state that might happen at an arbitrary time. Continuous characteristics of dynamic load are simulated by multiple discontinuous ones of static loads. The calculated sets of ESLs are applied as a multiple loading condition in the optimization process. A design cycle is defined as a circulated process between an analysis domain and a design domain. Design cycles are repeated until a design converges. The analysis domain gives a loading condition necessary for the design domain. The design domain gives a new updated design to be verified by the analysis domain in the next design cycle. This iterative process is quite similar to that of the multidisciplinary optimization technique. Even though the global convergence cannot be guaranteed, the proposed technique makes it possible to optimize the structures under dynamic loads. It has also applicability, flexibility, and reliability.

RF 콘센트를 이용한 가정 대기전력 모니터링

김경태 ( Gyeong-tae Kim ),박경진 ( Gyeong-jin Park ),최우혁 ( Woo-hyeok Choi ),김우성 ( Woo-sung Kim ) 한국정보처리학회 2013 한국정보처리학회 학술대회논문집 Vol.20 No.1

본 논문에서는 효율적인 전력사용을 위해 가정에서 사용하는 대기전력을 모니터링 할 수 있는 시스템을 구현하였다. 무선 근거리 통신을 지원하는 RF통신을 이용한 콘센트를 이용하여 가전기기의 현 상태에 따라 평균 전력량을 대입, 예상 전력량을 계산하여 임베디드 보드 및 스마트폰에서 전력량을 실시간으로 모니터링 할 수 있도록 시스템을 구현 하였다.

설계변수의 공차를 고려한 구조물의 강건 최적설계

이권희,박경진,Lee, Gwon-Hui,Park, Gyeong-Jin 대한기계학회 1997 大韓機械學會論文集A Vol.21 No.1

The optimization techniques have been applied to versatile engineering problems for reducing manufacturing cost and for automatic design. The deterministic approaches or op5imization neglect the effects on uncertainties of design variables. The uncertainties include variation or perturbation such as tolerance band. The optimum may be useless when the constraints considering worst cases of design variables can not be satisfied, which results from constraint variation. The variation of design variables can also give rise to drastic change of performances. The two issues are related to constraint feasibility and insensitive performance. Robust design suggested in the present study is developed to gain an optimum insensitive to variation on design variables within feasible region. The multiobjective function is composed to the mean and the standard deviation of original objective function, while the constraints are supplemented by adding penalty term to original constraints. This method has a advantage that the second derivatives of the constraints are not required. A mathematical problem and several standard problems for structural optimization are solved to check out the usefulness of the suggested method.

독립 공리를 이용한 구조 최적화 방법론 개발

이광원,박경진,Lee, Gwang-Won,Park, Gyeong-Jin 대한기계학회 2000 大韓機械學會論文集A Vol.24 No.10

The Design Axioms provide a general framework for design methodologies. The axiomatic design framework has been successfully applied to various design tasks. However, the axiomatic design has been rarely utilized in the detailed design process of structures where the optimization technology is generally carried out. The relationship between the axiomatic design and the optimization is investigated and Logical Decomposition method is developed for a systematic structural optimization. The entire optimization process is decomposed to satisfy the Independence Axiom. In the decomposition process, design variables are grouped according to sensitivities. The sensitivities are evaluated by the Analysis of Variance(ANOVA) to avoid considering only local values. The developed method is verified through examples such as the twenty -five members transmission tower and the two -bay-six-story frame.

레이저 마커용 빔 정렬장치의 공리적 설계

신광섭,이정욱,박경진,Sin, Gwang-Seop,Lee, Jeong-Uk,Park, Gyeong-Jin 대한기계학회 2002 大韓機械學會論文集A Vol.26 No.9

The usage of beam scanning type laser marker is rapidly increasing in the field of semiconductor equipment. A device called ″beam adjuster″ is employed to adjust the visible diode laser, which points the marking position for various setting. The device is very sensitive to manufacturing tolerance and assembly condition. Axiomatic approach has been applied to the design of the device. An existing design is analyzed based on the Independence Axiom. The existing design is found to violate the axiom. Two new designs are proposed to satisfy the Independence Axiom. The Information Axiom is utilized to evaluate the designs. A design is selected to have the minimum information content. The significance of this research is that a full cycle of axiomatic design is applied to a real engineering product.

최적화를 이용한 단순 유화 요소 모델링 기법 개발

이광원,석일우,박경진,Lee, Gwang-Won,Seok, Il-U,Park, Gyeong-Jin 대한기계학회 2001 大韓機械學會論文集A Vol.25 No.1

As computer power is increased, refined finite element models are employed for structural analysis. However, it is difficult and expensive to use refined models in the design stage. The refined models especially cause problems in the preliminary design where the design is frequently changed. Therefore, simplified models are needed. The simplification process is regarded as an empirical technique. Simplified and equivalent finite element model of a structure has been studied and used in the preliminary design. A general approach to establish the simplified and equivalent model is presented. The generated simple model has satisfactory correlation with the corresponding refined finite element model. An optimization method, the Goal Programming algorithm is used to make the simple model. The simplified model is used for the design change and the changed design is recovered onto the original design. The presented method was verified with three examples.