• 한국정보과학회논문지:소프트웨어및응용
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• 제27권9호
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• pp.952-960
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• 2000

본 논문에서는 퍼지 자동회귀 이동평균 (Fuzzy Auto-Regressive Moving Average, FARMA)제어기를 전력계통의 비선형 2기 5모선 (Two Machine - Five Bus)모형의 주파수 안정화에 적용한 결과를 제시한다 퍼지 자동회귀 이동 평균 제어기는 기존의 전문가에 의존하였던 퍼지제어 규칙을 실시간으로 형성해 나가는 구조이다. 복잡성, 비선형성 등 전력계통의 일반적인 특징들을 기술하고, 그 특징을 표현할 수 있는 비선형 2기5모선 모형을 제시한다. 제시된 모형을 바탕으로 기존 제어 방식과의 성능 비교를 실시하였고, 이를 통하여 FARMA 제어기의 우수성을 확인하였다.

• 한국정밀공학회지
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• 제11권2호
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• pp.85-94
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• 1994

The cutting mechanism of ultrasonic vibration machining is characterized as two phases, that is, an impact at the cutting edge and a reduction of cutting force due to non-contact interval between tool and workpiece. In this paper, in order to identify cutting dynamics of a system with ultrasonically vibrated cutting tool, an ARMA modeling is performed on experimental cutting force signals which have a dominant effect on cutting dynamics. The aim of this study is, through Dynamic Date System methodology, to find the inherent characteristics of an ultrasonic vibration cutting process by considering natural frequency and damping coefficient. Surface roughness and stability of cutting process under ultrasonic vibration are also considered

• 기계저널
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• 제28권2호
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• pp.169-174
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• 1988

신호처리 및 해석에 대한 교육효과를 증대시키기 위해서는 응용사례의 발굴, 프로젝트 개발, P C를 이용한 그래픽스 교육도 이루어져야 하며, 스펙트럼 분석기술 이외에 시간영역 파라미터 모형에 의한 신호해석기법〔예를 들어 자동회귀-이동평균(ARMA)등의 시계열 모형화〕도 최근 에는 실시간 응용의 가능성이 높아지는 추세에 있으므로 PC를 이용한 신호처리 및 해석 교육에 반영하는 것이 바람직하다.

• 한국기계가공학회지
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• 제1권1호
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• pp.123-132
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• 2002

In this study, the static and dynamic characteristics of endmilling process was modelled and the analytic realization of chatter mechanism was discussed. In this regard, We have discussed on the comparative assessment of recursive time series modeling algorithms that can represent the machining process and detect the abnormal machining behaviors in precision endmilling operation. In this study, simulation and experimental work were performed to show the malfunctional behaviors. For this purpose, new recursive least square method (RLSM) were adopted for the on-line system identification and monitoring of a machining process, we can apply these new algorithms in real process for detection of abnormal chatter. Also, The stability lobe of chatter was analysed by varying parameter of cutting dynamices in regenerative chatter mechanics.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2001년도 춘계학술대회 논문집
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• pp.971-974
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• 2001

In this study, the static and dynamic characteristics of endmilling process was modelled and the analytic realization of chatter mechanism was discussed. In this regard, We have discussed on the comparative assessment of recursive time series modeling algorithms that can represent the machining process and detect the abnormal machining behaviors in precision endmilling operation. In this study, simulation and experimental work were performed to show the malfunctional behaviors. For this purpose, new recursive(RLSM) were adopted for the on-line system identification and monitoring of a machining process, we can apply these new algorithms in real process for detection of abnormal chatter. Also, the stability lobe of chatter was analysed by varying parameter of cutting dynamices in regenerative chatter mechanics.

• 한국기계기술학회지
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• 제13권3호
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• pp.73-79
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• 2011

In this study, an analytical realization of end-milling system was introduced using recursive parametric modeling analysis. Also, the numerical mode analysis of end-milling system with different conditions was performed systematically. In this regard, a recursive least square modelling algorithm and the natural mode for real part and imaginary one was discussed. This recursive approach (RLSM) can be adopted for on-line end-milling identification. After experimental practice of the end-milling, the end-milling force was obtained and it was used for the calculation of FRF (Frequency response function) and mode analysis. Also the FRF was analysed for the prediction of a end-milling system using recursive algorithm.

• 정보처리학회논문지:소프트웨어 및 데이터공학
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• 제7권6호
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• pp.239-248
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• 2018

4차 산업혁명 시대가 도래하면서 기존 IoT에 감성지능이 포함된 신기술들이 연구되고 있다. 그 중 현재까지 다양하게 진행된 음악 서비스 제공을 위한 감성 분석 연구에서는 인공지능, 패턴인식 등을 활용한 사용자의 감성 인식 및 분류 등에만 초점을 맞추고 있는 상황이나, 사용자의 특정 감성에 해당하는 음악들을 어떻게 자동적으로 분류할지에 대한 감성별 음악 분류기법들에 대한 연구는 매우 부족한 상황이다. 본 연구에서는 최근 각광을 받고 있는 사람들의 감성과 관련된 음악관련 서비스를 개발할 시, 음악을 감성 범위에 따라 높은 정확도로 분류할 수 있도록 하는 감성 기반 자동 음악 분류기법을 제안한다. 데이터수집 시 Russell 모델을 바탕으로 설문조사를 하였으며, 음악의 특성으로 평균파장크기(Average amplitude), peak평균(Peak-average), 파장 수(The number of wavelength), 평균파장 길이(Average wavelength), BPM(Beats per minute)을 추출하였다. 해당 데이터들을 바탕으로 회귀 분석을 이용하여 다중회귀식을 도출하였으며, 각 감성에 대한 표준 수치들을 도출하여 새로운 음악 데이터와 해당 각 감성에 대한 표준 수치들과의 거리 비교를 통해 음악의 감성을 분류시키는 작업을 실시하였다. 이를 통해 나온 결과에 회귀분석을 통하여 나온 데이터를 대입하여 해당 데이터와 각 감성들의 비율을 통해 최종적으로 판단된 감성을 추출하였다. 본 연구에서 실험한 감성 일치율의 2가지 방식에 대해서 제안한 기법의 경우 70.94%, 86.21%의 일치율이 나왔고, 설문참가자들의 경우 66.83%, 76.85%의 일치율이 나옴으로써, 연구 기법을 통한 감성의 판단이 설문참가자들의 평균적인 판단보다 4.11%, 9.36%의 향상된 수치를 제공함을 알 수 있었다.

• 동력기계공학회지
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• 제2권2호
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• pp.73-80
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• 1998

The identification of drilling joint dynamics which consists of drilling and structural dynamics and the on-line time series detection of malfunction process is substantial not only for the investigation of the static and dynamic characteristics but also for the analytic realization of diagnostic and control systems in drilling. Therefore, We have discussed on the comparative assessment of two recursive time series modeling algorithms that can represent the drilling operation and detect the abnormal geometric behaviors in precision roundshape machining such as turning, drilling and boring in precision diemaking. For this purpose, simulation and experimental work were performed to show the malfunctional behaviors for drilling operation. For this purpose, a new two recursive approach (Recursive Extended Instrument Variable Method : REIVM, Recursive Least Square Method : RLSM) may be adopted for the on-line system identification and monitoring of a malfunction behavior of drilling process, such as chipping, wear, chatter and hole lobe waviness.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1993년도 춘계학술대회 논문집
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• pp.160-165
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• 1993

The cutting mechanism of ultrasonic vibration machining is characterized as two phases, that is an impact at the cutting edge and a reduction of cutting force due to non-contact interval between tool and workpiece. In this paper, in order to identfy cutting dynamics of a system with ultrasonically vibrated cutting tool, an ARMA modelling is performed on experimental cutting force signals which have a dominant effect on cutting dynamics. The aim of this study is, through Dynamic Data System methodology, to find the inherent characteristics of an ultrasonic vibration cutting process by considering natural frequencyand damping coefficient. Surface roughness and stability of cutting process under ultrasonic vibration are also considered

• 한국공작기계학회논문집
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• 제10권4호
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• pp.76-83
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• 2001

In this study, the static and dynamic characteristics of turning process was modelled and the analytic realization of regen-erative chatter mechanism was discussed. In this regard, we have discussed on the comparative assessment of recursive times series modeling algorithms that can represent the machining process and detect the abnormal machining behaviors in precision turning operation. In this study, simulation and experimental work were performed to show the malfunction behaviors. For this purpose, new Recursive Extended Instrument Variable Method(REIVM) was adopted for the on-line system identification and monitoring of a machining process. Also, we can apply REIVE algorithms in real process for the detection of chatter frequency and dynamic property and analyze the stability lobe of the system by changing a parameter of cutting dynamics in regenerative chatter mechanics, if it is stable or unstable, Also, The stability lobe of chatter was analysed.