평판 모터 상태 관측을 위한 비선형 관측기

김원희(Wonhee Kim),정정주(Chung Choo Chung) 대한전기학회 2010 전기학회논문지 Vol.59 No.12

To improve the performances of Sawyer motors and to regulate yaw rotation, various feedback control methods have been developed. Almost all of these methods require information on the position, velocity or full state of the motor. Therefore, in this paper, a nonlinear observer is designed to estimate the full state of the four forcers in a Sawyer motor. The proposed method estimates the full state using only positional feedback. Generally, Sawyer motors are operated within a yaw magnitude of several degrees; outside of this range, Sawyer motors step out. Therefore, this observer design assumes that the yaw is within ±90º. The convergence of the estimation error is proven using the Lyapunov method. The proposed observer guarantees that the estimation error globally exponentially converges to zero for all arbitrary initial conditions. Furthermore, since the proposed observer does not require any transformation, it may result in a reduction in the commutation delay. The simulation results show the performance of the proposed observer.

Nonlinear Controller for the Velocity Tracking and Rejection of Sinusoidal Disturbances in Permanent Magnet Stepper Motors

김원희(Wonhee Kim),강동규(Dong Gyu Gang),한종표(Jonhpyo Han),정정주(Chung Choo Chung) 대한전기학회 2011 전기학회논문지 Vol.60 No.3

In this paper, a nonlinear controller is proposed to track the desired velocity and to cancel sinusoidal disturbances. The proposed method consists of a velocity tracking controller and internal model principles (IMPs). For the design of the velocity tracking controller, mechanical and electrical dynamic controllers are independently designed. For the mechanical dynamics, the velocity tracking controller generates the desired quadrature current to track the desired velocity. The current tracking controller is designed to guarantee the desired quadrature current and to regulate the direct current. Therefore, the proposed velocity tracking controller has a field-oriented control. Since the controllers of the mechanical and electrical dynamics are independently designed, the stability of the closed-loop system is demonstrated using passivity. Since both the cogging torque and DC current errors act as sinusoidal disturbances in PMSM, we use four add-on type IMPs that preserve the merits and performance of the pre-designed controller without sacrificing the closed-loop stability. The performance of the proposed method is validated via simulations.

딥러닝 기반 음악 분류 모델 연구 동향

김원희(Wonhee Kim),이기용(Ki Yong Lee) 한국정보과학회 2022 한국정보과학회 학술발표논문집 Vol.2022 No.06

Passivity based Nonlinear controller for Position Tracking Control of Electro-Hydraulic Servo System

Wonhee Kim(김원희),Jongpyo Han(한종표),Indeok Choi(최인덕),Daehee Won(원대희),Chung Choo Chung(정정주) 제어로봇시스템학회 2008 제어로봇시스템학회 국내학술대회 논문집 Vol.2008 No.10

This paper presents a passivity controller for position control of electro-hydraulic servo system. Passivity based controller was designed to consider 5th order state space model of the hydraulic actuator which has a second order servo valve dynamics. Simulation results showed that position tracking performance of proposed controller is effective by bandwidth, step response, and path tracking test.

남중국해 해양분쟁 관련 ‘국제법 전쟁(Lawfare)’의 성과와 과제

김원희(KIM Wonhee) 대한국제법학회 2016 國際法學會論叢 Vol.61 No.4

유엔해양법협약(이하 ‘해양법협약’) 제7부속서에 따라 설립된 중재재판소는 2016년 7월 12일 필리핀과 중국 간 남중국해 중재사건에 대해 본안 판정을 내렸다. 남중국해 중재사건은 국제법 학자들뿐만 아니라 다양한 전문가들과 세계 여론으로부터도 비상한 관심을 끌어 왔다. 동남아시아의 많은 분쟁당사국들이 복잡하게 얽힌 남중국해의 영토 및 해양분쟁이 최초로 국제재판에 회부되었고, 미국과 패권 경쟁을 벌이고 있는 중국이 해양법협약상 강제적 분쟁해결절차의 피소국이 됨으로써 공세적인 해양관할권 확대 정책에 국제법적 제동이 걸릴 수 있을 것인지를 둘러싸고 전 세계의 이목과 관심이 이 사건에 집중되었다. 중재재판소는 필리핀이 중국과의 해양분쟁을 처음 중재절차에 회부했던 2013년 1월 22일부터 3년 6개월이 지난 2016년 7월에 본안 판정을 내렸다. 해양법협약 제7부속서의 중재재판 절차임을 감안하더라도 중국이 중재절차에 불참한 상황에서 비교적 신속하게 절차가 진행되었다. 중재재판소는 중국의 불참에도 불구하고 궐석재판을 진행하여 본안 단계에서 필리핀의 청구취지를 대부분 인용하였고 필리핀의 승소 판정을 내렸다. 이번 중재판정은 해양법협약에 대한 혁신적 해석을 통해 해양법의 발전과 남중국해 해양분쟁의 평화적 해결에 기여했다는 평가를 받고 있으나 동시에 불출석한 중국에게 불리한 사실관계를 추론하거나 다소 자의적으로 해양법협약을 해석하고 적용했다는 비판을 받고 있다. 이 논문의 목적은 상반된 평가를 받고 있는 남중국해 중재판정이 중요하게 다루었던 국제법적 쟁점들을 검토하고 중재재판소가 제시한 판결이유와 판결과정을 상세히 분석하는 것이다. 필리핀과 중국 간의 남중국해 중재판정은 직접 당사국이 아닌 한국에게도 여러 가지 측면에서 중요한 의미를 가지고 있으므로 이 글에서는 중재판정에 대한 국제법적 검토와 분석을 바탕으로 한국에 대해 제공하고 있는 함의를 도출하고 그에 관한 정책제언을 제시하고자 한다. On 12 July 2016, the arbitral tribunal issued the Award on the Merits in the South China Sea Arbitration with unanimous decision. The South China Sea arbitration has been attracted worldwide attention and concerns due to its gravity of confrontation between China and the Philippines and hegemonic struggle behind the scene between China and the United States in East Asia region. It took only three years and six months for the tribunal to render the final award after the beginning of the case on 22 January 2013 despite of China’s non-participation throughout the whole procedures. The tribunal finally decided to accept almost every submissions by the Philippines and deny most of contentions raised in the Position Paper of 7 December 2014 published by China. After the award on the merits, many international law scholars and practitioners have been presenting conflicting and different views on the award. Some attribute a great tribute to the Tribunal for clarifying the relevant provisions of the UNCLOS which were required for interpretation, while others present a critical review on the main findings and reasoning of the award. The evaluation of the award on the merits is very controversial among scholars and practitioners. The award on the merits is receiving not only favorable comments but also sever criticism at the same time. The aim of this paper is to examine the legal issues mainly dealt by the tribunal and to critically analyze the main reasoning and its legal and factual grounds of the award. Moreover, the findings of the award have significant implications for the ocean law and policy of the State parties to the UNCLOS as well as non-party States. This paper will suggest policy recommendations for the Republic of Korea on the prospects for the Annex VII arbitration under the UNCLOS and on the marine policy with regard to the legal status of maritime features.

성인의 내현적 자기애가 전위 공격성에 미치는 영향 : 부정 긴급성의 매개효과

김원희(Kim, Wonhee),박철옥(Park, Cholok) 한국재활심리학회 2020 재활심리연구 Vol.27 No.3

본 연구에서는 내현적 자기애와 전위 공격성의 관계에서 부정 긴급성의 매개효과를 검증하였다. 연구의 목적에 따라 전국의 만 18세 이상 64세 이하 성인 남녀를 대상으로 내현적 자기애, 전위 공격성, 부정 긴급성을 측정하는 오프라인과 온라인 설문을 실시하였다. 총 626명을 대상으로 한 설문에서 불성실하게 응답한 61명의 자료를 제외한 565부를 분석에 사용하였다. 결과분석에는 SPSS 21.0과 Mplus 7.0을 사용하였다. 연구 결과는 다음과 같다. 첫째, 상관분석을 실시하여 주요 변인들간의 관계를 확인한 결과, 내현적 자기애와 전위 공격성, 부정 긴급성 간에 모두 유의한 정적 상관이 있었다. 둘째, 연구모형을 검증한 결과, 내현적 자기애와 전위 공격성의 관계에서 부정 긴급성의 부분매개효과가 확인되었다. 이를 바탕으로 본 연구의 의의와 상담 장면에서의 시사점, 후속연구를 위한 제언 등을 논의하였다. This study examined the mediating effect of negative urgency in the relationship between covert narcissism and displaced aggression. According to the purpose of the study, offline and online surveys were conducted to measure covert narcissism, displaced aggression and negative urgency for adult men and women age 18 to 64 in Korea. A total of 565 respondents were used for the analysis, excluding 61 respondents who responded insincerely among 626 respondents. SPSS 21.0 and Mplus 7.0 were used for the analysis. The results of the study are as follows. First, as a result of confirming the relationship between the main variables through correlation analysis, there were significant positive correlations between covert narcissism, displaced aggression, and negative urgency. Second, as a result of verifying the research model, the partial mediating effect of negative urgency was confirmed in the relationship between covert narcissism and displaced aggression. Based on the results, the implications of this study, implications in the counseling scene, and suggestions for follow-up studies were discussed.

사출-구조 연계해석을 이용한 정션블록 조립성 검증 해석

김원희(Wonhee Kim),김영훈(Younghun Kim),변혜경(HyeKyeong Byeon) 한국자동차공학회 2017 한국자동차공학회 학술대회 및 전시회 Vol.2017 No.11

스테퍼 모터를 위한 비선형 제어기법의 개관

김원희(Wonhee Kim),신동훈(Donghoon Shin),이영우(Youngwoo Lee),정정주(Chung Choo Chung) 제어로봇시스템학회 2014 제어·로봇·시스템학회 논문지 Vol.20 No.3

Stepper motor is widely used in positioning applications due to its durability and high torque to inertia ratio as well as low cost and ability to be easily controlled with open-loop. Due to increased resolution of position control and improved stability of motion control, microstepping has drawn attention in industry since it was introduced in 1970s. With the increase in computational power and decrease in cost of embedded processors in recent years, drives and control systems for stepper motors have become more sophisticate than ever. Thus, closed-loop control methods have been developed to improve the performance of the stepper motors. In this paper, we review not only basic principles of conventional control methods used for stepper motors but also that of microstepping control. In addition, we surveyed recent development in nonlinear control methods applied to stepper motors. The nonlinear control methods are presented in the view of Lyapunov stability. Nonlinear torque disturbance observer, sliding mode control, and nonlinear phase compensation are also presented.

우크라이나와 러시아 간의 크림반도 분쟁에서 국제법의 한계와 역할

김원희(Kim, Wonhee) 국제법평론회 2021 국제법평론 Vol.- No.59

By a municipal law act dated March 21, 2014, the Russian Federation annexed Crimea, a part of Ukraine. This act followed armed intervention by forces of the Russian Federation, a referendum, and a declaration of independence in Crimea. Since the foundation of the United Nations, few claims of annexation following the use of force have been made. This is the first case of annexation by a permanent member of the Security Council against a member of the UN. Given the Crimean crisis, Ukraine initiated several international proceedings against the Russian Federation before various forums by invoking the relevant treaties and customary international law. The present article examines the inter-State litigation by Ukraine against Russia before some international courts and tribunals including the European Court of Human Rights, the International Court of Justice, and Annex VII Arbitral Tribunal under the United Conventions on the Law of the Sea. It then considers the judgments rendered by the international courts and tribunal on the applications by Ukraine against Russia since the outbreak of Ukraine crisis in 2014. Based on the examination of the above jurisprudence on the preliminary objection, it will analyze the limits and role of international law in the settlement of the disputes between Ukraine and the Russian Federation.

ICCB 낙하해석 정합성 향상을 위한 고무물성 적용방안 연구

김원희(Wonhee Kim) 한국자동차공학회 2021 한국자동차공학회 학술대회 및 전시회 Vol.2021 No.11