전력 계통 과도상태 안정화를 위한 비선형 적응 백스테핑 제어기 설계

金東憲(Dong-Hun Kim),金洪必(Hong-Pil Kim),梁海元(Hai-Won Yang) 대한전기학회 2000 전기학회논문지A Vol.49 No.7

아이폰 기반의 이동로봇 시뮬레이터 개발

김동헌(Dong Hun Kim) 한국지능시스템학회 2013 한국지능시스템학회논문지 Vol.23 No.1

본 논문은 애드혹 통신을 기반으로 아이폰의 가속도 센서를 사용하여 이동로봇을 무선 제어하는 연구에 대하여 다룬다. 이동로봇을 아이폰으로 무선제어하기 위한 방법으로 사용자 원격제어와 자율제어 방법이 제안되었다. 궤적 추종제어 알고리즘의 효율성을 평가하기 위하여 아이폰의 인터페이스를 기반으로 모니터에 그려진 궤적을 가상로봇이 추종하는 시뮬레이터를 개발하였다. 제안된 시뮬레이터에서는 궤적 추종제어를 위해 이동로봇을 제어할 때 컴퓨터에서 해당 알고리즘을 이용하여 미리 시뮬레이션이 가능하며 사용자에 의한 원격제어와의 결과 비교도 보여준다. 연구의 결과로 제안된 시뮬레이터가 이동로봇에 자율이동제어 방법을 사용할 때, 자율추종 알고리즘의 적합성과 효율성을 미리 검사 하는데 사용될 수 있음을 보여준다. This study presents the remote control of a mobile robot using iPhone based on ad hoc communication. Two control interfaces are proposed to control a mobile robot using iPhone : Remote control by a user and autonomous control. To evaluate the effectiveness of algorithms for trajectory following, a simulator are developed where a virtual robot follows a referenced trajectory in a monitor by iPhone interface. In the proposed simulator, some algorithms are tested how they work well or not for trajectory following of a mobile robot. Comparative results by remote user control and autonomous control are shown. Results of an experiment show that the proposed simulator can be effectively used for testing the effectiveness of autonomous tracking algorithms.

자동차 클러스터의 감시 및 제어를 위한 모델기반설계 기법 연구

김동헌(Dong Hun Kim) 한국지능시스템학회 2017 한국지능시스템학회논문지 Vol.27 No.1

본 연구는 모델기반설계 기법을 이용하여 자동차 클러스터의 감시 및 제어를 하는 스테이션을 설계한다. 설계 도구로 매트랩 GUI(Graphic User Interface), M 프로그램, 시뮬링크(simulink), 스테이트 플로우(state flow), 툴박스(tool box)를 사용하여 실제 자동차 클러스터 시스템과 연동하여 자동차에서 들어오는 경고, 인터럽트 등의 각종 정보 등을 감시한다. 감시 수단으로는 PC(Personal Computer) 스테이션을 사용하여 자동차 클러스터 설계 시 툴 박스의 인터페이스 명령함수가 실제 자동차 클러스터 시스템과 연동하게 한다. 따라서, 기존의 텍스트 방식과 달리 모델기반설계로 개발된 자동차 클러스터 시스템은 각 기능 및 알고리즘을 블록과 상태플로우로 프로그램에 따라 작성하기 때문에 알고리즘의 수정이나 기능 추가가 용이하며, 또한, PC를 통해 모니터 상에서 동작 알고리즘을 검증하기 때문에 클러스터의 개발과 수정에 따른 많은 시간과 비용을 절감할 수 있는 효과를 준다. This paper presents the development of a monitoring and control system for a vehicle cluster using a model-based design technique. For MBD(model-based design), MATLAB GUI(Graphic User Interface), M programs, simulink, state flow, and tool boxes are used to monitor a number of data such as warning, interrupts, and etc. connected to a real vehicle cluster. As a monitoring tool, a PC(Personal Computer) station interworks with the real vehicle cluster through the interface commands of tool boxes. Thus, unlike existing text-based designs, the MBD based vehicle cluster system provides very easy algorithm updates and addition, since it offers a number of blocks and state flow programs for each functional actions. Furthermore, the proposed MBD technique reduces the required time and cost for the development and modification of a vehicle cluster, because of verification and validation of the cluster algorithm on the monitor through a PC.

울산광역시 장애인 구강건강증진을 위한 자원봉사 중심의 지속적 치과진료사업의 사례

김진범(Jin-Bom Kim),김병재(Byung-Jae Kim),한동헌(Dong-Hun Han),전은주(Eun-Joo Jun),김한나(Han-Na Kim),김민지(Min-Ji Kim) 대한치과의사협회 2015 대한치과의사협회지 Vol.53 No.11

The purpose of this study was to evaluate the oral health promotion of the disabled persons by voluntary dental services in Ulsan Metropolitan City. Two dentists taken a calibration training for national oral health survey examined the oral health status of 473 disabled persons from two special schools for the disabled children and adolescents, a residential facility and a gymnasium for the disabled persons in 2009-2010. The surveyed disabled persons in the age range was from 7 to 74 years old. Voluntary dentists, oral hygienists and other civilian volunteers had supplied with the oral health care services to the disabled persons at dental clinics of special schools for the disabled children and adolescents, and a dental clinic supported from Nam-Gu Public Health Center in Ulsan Metropolitan City since 1997. The obtained data from these surveys were analyzed with the SPSS statistical package. Among subjects aged 12-14 years, subjects with decayed, missing and filled teeth (DMFT) in permanent dentition was 46.9%; subjects with untreated decayed teeth, 17.2%. The number of decayed, missing and filled teeth in permanent dentition was 1.36. The proportion of decayed components of DMFT score was 28.00%; proportion of missing components of DMFT score, 1.43%; proportion of filled components of DMFT score, 70.57%. The proportion of filled components of DMFT score among disabled persons of all age group in Ulsan were evaluated to be a similar level to non-disabled citizens in Ulsan from 2010 Korean National Survey. The oral health care programs for disabled persons by voluntary services of dental professionals and other civilians are evaluated to be effective for the oral health promotion of disabled persons in Ulsan.

Flexible and Scalable Formation for Unicycle Robots

Dong Hun Kim(김동헌),Young Kwun Lee(이용권),Sung-Ill Kim(김성일),Wee-Jae Shin(신위재),Hyun-Woo Lee(이현우) 한국지능시스템학회 2005 한국지능시스템학회 학술발표 논문집 Vol.15 No.2

This paper presents a self-organizing scheme for multi-agent swarm systems based on coupled nonlinear oscillators (CNOs). In this scheme, unicycle robots self-organize to flock and arrange group formation through attractive and repulsive forces among themselves. It is also shown how localized distributed controls are utilized throughout group behaviors such as formation and migration. In the paper, the proposed formation ensures safe separation and good cohesion performance among the robots. Several examples show that the proposed method for group formation performs the group behaviors such as reference path following, obstacle avoidance and flocking, and the formation characteristics such as flexibility and scalability, effectively.

불확실성 적응기법을 이용한 비선형 시스템의 강인 백스테핑 설계

김동헌(Dong-Hun Kim),김응석(Eung-Seok Kim),양해원(Hai-Won Yang) 제어로봇시스템학회 2001 제어·로봇·시스템학회 논문지 Vol.7 No.7

시판 차 음료 속에 함유된 불소의 농도 측정 및 연령별 불소섭취량 추정

한동헌 ( Dong Hun Han ),이운정 ( Un Jung Lee ),김동현 ( Dong Hyun Kim ),김민지 ( Min Ji Kim ),황수정 ( Su Jung Hwang ),김진범 ( Jin Bom Kim ) 대한예방치과·구강보건학회 2010 大韓口腔保健學會誌 Vol.34 No.3

Objectives. The purpose of this study was to analyze the fluoride concentrations of tea drinks which were commercially available in Korea in 2009 and to predict amount of daily fluoride intake from tea drink according to different age groups. Methods. The fluoride concentrations of 20 kinds of tea drinks were assessed by a fluoride ion selective electrode. The estimates of daily fluoride intake were assumed by Dietary Reference Intakes for Koreans 2005. Results. The fluoride concentrations of tea drinks were 0.03~1.72 ppm (mean 0.51 ppm). The calculated amount of daily fluoride intake which were supposed to drink all the sufficient water intake by tea drink of 1.72 ppm fluoride were over maximum intake of fluoride under 9 years olds and over sufficient intake of fluoride in all age groups. Those of 0.51 ppm fluoride were under maximum intake of fluoride in all age groups and over sufficient intake of fluoride under 5 months olds infants. Conclusions. Based on this study, most of the tea drink in Korea contained the appropriate concentration of fluoride. However, consuming some tea drink available in Korean market in large quantities may lead to exposion to a high amount of fluoride which may cause dental fluorosis in infants and young children. Although most of tea drinks are safer to consume, fluoride concentrations of some tea drinks are too low for caries prevention. In countries such as Korea where tea is traditionally consumed, the fluoride concentration and daily safety precautions should be indicated on tea products.

비서 실무실습실 운영에 관한 모형 프로그램 개발

김동헌(Dong-Hun Kim) 한국비서학회 1996 비서·사무경영연구 Vol.4 No.-

Ethylene glycol에 의해 액화된 폐지로부터 polyester 제조

김동헌(Dong Hun Lee),김창준(Chang-Joon Kim),김성배(Sung Bae Kim) 한국생물공학회 2011 KSBB Journal Vol.26 No.3

Polyester was prepared through the esterification reaction between watsepaper liquefied by ethylene glycol and carboxylic acid. Liquefaction was carried out at the previously determined condition of 100 minutes, 160℃, and 3% sulfuric acid, and the hydroxyl value of the liquefied product was 411 mg KOH/g. In order to remove bubbles produced during the curing step, the method to introduce a slight nitrogen stream into reaction vessel and/or the method to preheat a polyester film at 85℃ before curing step were used alone or in combination. But if curing temperature was 130℃, simple method to cure a film for 5 hours at 130℃ without using both methods was found to be most effective. The polyesters prepared with various carboxylic acids showed significant different physical properties, and maleic acid was best among them. Also, the effect of reaction time and temperature, C/H (carboxyl group/hydroxyl group) ratio, and type of additive on the crosslinkage of polyester was investigated. Lithium hydroxide or citric acid as additive was used to enhance the crosslinkage of polyester and citric acid was proved to be much more effective than lithium hydroxide. The effect of reaction temperature on the crosslinkage was marginal, but the crosslinkage decreased above 130℃. The crosslinkage was 86% when the polyester was prepared at an optimum condition such as 130℃ and 15 minutes of reaction condition, 1.5 of C/H ratio, 130℃ and 5 hours of curing condition, and 10% addition of citric acid.

계단식 관측기에 의한 수중 차의 상태추정

김동헌(Dong Hun Kim) 한국지능시스템학회 2009 한국지능시스템학회논문지 Vol.19 No.2

본 논문은 수중 차의 차속도와 프로펠러 각속도를 추정하는 문제를 다룬다. 계단식 관측기는 측정된 위치 값으로부터 속도 값 추정을 위해 사용한다. 고이득 관측기(high-gain observer)에 전형적으로 생기는 전형적인 문제를 없애기 위하여 계단식 구조의 관측기가 설계되었다. 고이득 관측기처럼 시스템 다이나믹스와 파라미터로부터 무관하게 설계할 수 있으며, 단순한 구조를 가진다. 관측기의 첫 단계에서 출력 값이 추정되고, 측정된 출력의 1계 미분 값이 관측기의 두 번째 단계를 통해 추정된다. 또한 출력의 n 번째 미분 값은 관측기의 n+1 번째 단계에서 추정된다. 제안된 관측기가 전체 점근적 안정도를 보장함을 보여준다. 시뮬레이션 결과는 기존의 고이득 관측기에 비해 제안된 관측기가 수중 차의 차속도와 프로펠러 각속도를 더 우수하게 추정함을 보여준다. This paper investigates the estimation problem of vehicle velocity and propeller angular velocity on the underwater vehicle. Inspired by but different from a high-gain observer, the cascade observer features a cascade structure and adaptive observer gains. In doing so the cascade observer attempts to overcome some of the typical problems that may pose to a high-gain observer. As in the case of a high-gain observer, the cascade observer structure is simple and universal in the sense that it is independent of the system dynamics and parameters. A cascade observer is used for the estimation of velocity from measured position. In the 1st step of the observer, the output is estimated, and the 1st order derivative of measured output is estimated via the 2nd step of the observer. Also, nth order derivative of the output is estimated in the (n+1)th step of the observer. It is shown that the proposed observer guarantees globally asymptotical stability. By simulation results, the proposed observer scheme for the estimations of vehicle velocity and propeller angular velocity shows better performance than the scheme based on the existing observer.