직접토크제어에 의한 위치검출기 없는 리럭턴스 동기전동기의 고성능 제어시스템

김민회,김남훈,백원식 전력전자학회 2002 전력전자학회 논문지 Vol.7 No.1

This paper presents an implementation of digital high-performance position sensorless control system of Reluctance Synchronous Motor(RSM) drives with Direct Torque Control(DTC). The system consists of stator flux observer, speed and torque estimator, two digital hysteresis controllers, an optimal switching look-up table, Insulated Gate Bipolar Transistor(IGBT) voltage source inverter, and TMS320C31 DSP board. The stator flux observer is based on the combined voltage and current model with stator flux feedback adaptive control of which inputs are current and voltage sensed on motor terminal for wide speed range. In order to prove the suggested sensorless control algorithm for industrial field application, we have some simulation and actual experiment at low and high speed range. The developed high-performance speed control by fully digital system are shown a good response characteristic of control results and high performance features using 1.0[kW] RSM having 2.57 reluctance ratio of Ld/Lq. 본 논문은 직접토크제어에 의한 리럭턴스 동기 전동기의 위치센서 없는 고성능 제어시스템을 제안한다. 이 시스템은 고정자 자속관측기, 속도/토크 관측기, 두 개의 디지털 히스테리시스 제어기, 최적 스위칭 룩업 테이블, IGBT 전압형 인버터, 그리고 TMS320C31 DSP보드로 구성된다. 넓은 속도 범위에서의 안정된 응답특성을 얻기 위해서 전동기 단자에서 얻어진 전압과 전류를 사용하는 폐루프 자속관측기를 사용하였다. 개발된 고성능 속도제어 시스템의 동특성을 검증하기 위해서 1.0[kW] 리럭턴스 동기 전동기를 사용하여 시뮬레이션과 실험을 수행한 결과 저속영역과 고속영역 모두 우수한 동특성을 얻을 수 있었다.

맥신 홍 킹스턴의 『중국남자들』(China Men) : 역사적 기억에 관한 글쓰기와 다문화주의적 비전의 혼재

김민회 새한영어영문학회 2009 새한영어영문학 Vol.51 No.2

Andreas Huyssen indicates that a new network of memories, causing tension and conflicts with the mainstream memory, enables us to reconsider the essence of national identity, reinforced by the mainstream memory. Extending his idea, the study of this essay is to discuss the way in which Kingston uses Chinese Americans' historical memory to raise social, racial, multicuitural and political issues in defining their positionality in American society. Depicting BaBa's individual experience in the United States, she reveals how BaBa's traumatic memory in which he has had through immigration experience unstabilized his present self-identity. She, however, attempts to relocate him within a firm and stable subject as American through reinterpreting his traumatic memory. Kingston refuses the mainstream memory as determined, for the memory fails to fully represent the traumatic memory of how and why Chinese immigrants have suffered irrational and violent immigration laws and racialized social norms against such the ethnic others. Kingston aims to reveal such harsh and irrational laws and norms have psychologically and physically traumatized Chinese immigrants and Chinese Americans between America and China. Nevertheless, she seeks a possibility of overcoming such situations in the modes of multicultural American society by stressing that BaBa can be placed in a subject who writes his own individual history as American in American historical context with her deep sympathy.

Dilemma of Writer’s Individual Subjectivity and Self-Defense Mechanism in Don DeLillo’s Mao II

김민회 부산외국어대학교 외국어연구소 2017 외국어연구 Vol.30 No.-

Don DeLillo’s Mao II is one of the outstanding postmodern novels about the tension among writers, consumerism, and American society with terrorism. In this novel, DeLillo creates Bill Grey, a writer’s alter ego who keeps sauntering around the American society without establishing his own self as a writer. Bill attempts to resist the consuming society by rejecting the visual images created by mass media. However, escaping to the Middle East in order to face the truth or reality in life, he faces another problem such as terrorism which threatens the author’s subjectivity. By suggesting that Bill never escapes the consuming society, DeLillo creates a particular way of dealing with this issue. To avoid his dilemma of staying in the society as a writer, DeLillo attempts to describe it as a way to detach him from the issue itself and then produces the reinforced notion of creativity in Bill who always believes that his position as a writer will be recovered someday. In doing so, DeLillo at least keeps his subjectivity as a writer at the materialistic American society. Key words: postmodern, terrorism, alter ego, subjectivity, dilemma, creativity

충수대장 누공 1예

김민회,임덕호,김봉수,구진회,강행지,황용희,최건필 대한대장항문학회 2004 Annals of Coloproctolgy Vol.20 No.4

An appendicocolic fistula is a rare disease. It seems likely that the appendix becomes adherent to the viscus either before or after its perforation due to appendicitis, so surgeons may become confused when an emergency appendectomy in done. We report one case of an appendicocolic fistula to draw attention to the importance of this fistula and to describe the clinical, the diagnostic, and the therapeutic aspects of the disease.

미국의 PNGV 계획

김민회 전력전자학회 2000 전력전자학회지 Vol.5 No.2

Advanced High Frequency AC Propulsion System for Next Generation Electric Hybrid Vehicle

김민회 전력전자학회 1997 전력전자학회 논문지 Vol.2 No.1

본 논문은 PNGV 계획에 따른 차세대 전기자동차의 개발을 위하여 고주파 교류 전력분배 시스템을 적용하여 이용할 수 있는 추진력 장치의 구현 가능성에 대한 조사 연구이다. 실행 가능한 관점에서 전력 분배와 에너지원의 결합이 쉽게 이루어 질 수 있고 변환이 가능한 여러 가지 형태의 시스템이 비교 검토되었으며, 현재 기술 수준으로 보아 가까운 장래에 실현 가능한 최적의 시스템 구성은 배터리와 내연기관엔진 및 유도전동기를 이용하는 하이브리드형이 제시되었다. 각 시스템의 원활한 전력수급과 운전특성을 위하여 단상 고주파 교류 전력분배 제어기법을 적용하였으며, 이 시스템의 타당성을 입증하기 위하여 시스템 구성에 따른 모델링과 컴퓨터 시뮬레이션을 실시하였다. 이 결과 차세대 전기자동차용으로 제시된 고주파 교류 전력분배에 의한 하이브리드형 추진력 시스템이 가능하며 운전특성도 우수함을 보여주었다.

유기 박막 트랜지스터의 플렉서블 센서 응용 기술 동향

김민회 한국방송공학회 2015 방송과 미디어 Vol.20 No.2

존 에드가 와이드만의 『소떼 죽이기』: 역사적 사건의 재현과 흑인공동체를 위한 예언적 비전

김민회 새한영어영문학회 2020 새한영어영문학 Vol.62 No.1

Considered his most difficult novel, John Edgar Wideman’s The Cattle Killing well represents how the past and the present events are integrated into a single event under the notion of postmodern time concept. Often discussing it with the notion of metahistorical fiction, critics mainly assert that Wideman effectively uses the notion in order to relocate him as a postmodernism writer. However, his novel also suggests strategic representation of African American historical events in a way to reveal the present urgent issues such as racism and racial violence in his community. For example, comparing the Philadelphia fever in 1793 which led to the mass murder of African Americans and the Xhosa’s fall caused by their slaughter of the cattle in 1856 which was led by the female prophet’s wrong prophecy at the same time, he asserts that a racialized vision and its tragic result have occurred regardless of its time and space. He believes that the only way to prevent such tragedy is to have a prophetic leader who can learn valuable lessons from African American history with humanistic and rational mind. Alluding to W. E. B. Du Bois, Wideman attempts to find a leader like Du Bois throughout the American history who has been deemed to be a prophet to save African American community from the racial violence. For Wideman, only a proper leader can stop mass murdering of African Americans by using the lessons from the history and suggests a utopian vision of African American community freed from all racial violence.

줄리 오츠카의 『황제가 신성했을 때』에 나타난 인종주의 폭력과 모범적 소수민 수용의 의미

김민회 현대영미어문학회 2019 현대영미어문학 Vol.37 No.3

Julie Otsuka’s When the Emperor Was Divine has often been discussed in terms of the internment camp experience and the Japanese Americans’ trauma. It also gives us a chance to explore how the model minority is intertwined with the racially violent internment experience. From this point of view, this paper explores how the experience places the image of the model minority as acceptable within the Japanese American community even though it is represented as racial violence ingrained in American society. Describing an unnamed Japanese American family that moves to the camp according to Evacuation Order No. 9066 in 1942, the work seems to reveal their resistant attitude to the government order and its racial violence that forces them to degrade to ‘the second citizenship.’ However, all family members become more subject to the image of ‘obedient citizenship,’ which can be characterized as an aspect of the model minority. They accept the image of the model minority not only to survive in American society but also to accept the society as their homeland. .

퍼즐 확대 과제에 대한 초등학교 6학년의 협력적 수학 문제해결 특징 탐색

김민회,장혜원 대한수학교육학회 2020 학교수학 Vol.22 No.1

Collaborative problem solving is considered as a key competency for the 21st century. This study aims to obtain some didactical implications for teaching collaborative mathematical problem solving based on the analysis of the characteristics of the 6th graders’ collaborative mathematical problem solving processes. To do this, we provided a puzzle-enlarging task to twelve participants who grouped by four. Analyzing their solving process and dialogue, we can induce some conclusions: the participants who are in the different thinking levels could meaningful progress in their reasoning and their roles are complementary in a group, and the participants used cognitive skills as well as social skills which could supplement cognitive one. Finally, we suggested proper methods of grouping and importance of teachers’ intervention, need for developing some sub-skills, and collaboration-focused classroom culture for teaching collaborative mathematical problem solving. 21c를 살아갈 미래 인재를 위한 핵심 역량 중 하나로 협력적 문제해결력이 강조되는 바, 본 연구는 초등학교 6학년 학생들의 협력적 수학 문제해결 과정의 특징을 분석하고 그 결과에 기초하여 협력적 수학 문제해결 지도를 위한 교수학적 시사점을 얻는 것을 목적으로 한다. 이를 위해 3가지 유형의 4인 모둠에게 퍼즐 확대 과제를 제시하고 그들의 협력적 문제해결 과정에 나타난 특징을 분석함으로써 몇 가지 결과를 얻을 수 있었다. 서로 다른 사고 수준의 학생들이 협력적 수학 문제해결 과정에서 모둠 내 상보적인 역할을 통해 상호 사고를 발전시킬 수 있었고, 협력적 수학 문제해결에서 학생들이 사용하는 인지적 기능은 다소 제한적이었으나 사회적 기능을 활용하여 이를 보완하였다. 이와 같은 연구 결과에 기초하여, 협력적 수학 문제해결 지도를 위한 교수학적 시사점으로 적합한 모둠 구성방식과 교사의 개입 선택의 중요성, 다양한 인지기능의 활용에 대한 지도의 필요성 등을 도출하였다.