• 대한기계학회논문집A
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• 제26권5호
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• pp.843-850
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• 2002

This paper presents a simulation method using the transmission line modeling to reduce simulation runtime of hydraulic control systems. This method is based on separating the system components each other using the transmission line elements prior to simulation, which leads to divide the simulated system into several subsystems suitable for an even more efficient integration. It can also handle nonlinearities and discontinuities without flag signal when restarting integration. By applying variable integration timestep to parallel hydraulic circuits via parallel processing, it is shown that simulation run-time can be reduced significantly compared with that of Runge Kutta method.

• 전기학회논문지
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• 제62권12호
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• pp.1725-1729
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• 2013

In this paper, the modeling and simulation of infrared absorption in an infrared absorbing structure with the cascaded transmission line model were carried out. Each layer in the infrared absorbing structure can be modeled as a characteristic impedance of the cascaded transmission line model. The simulation results show that the cavity thickness to get a maximum absorption should be less than a quarter wavelength, which is somewhat different from prevalent thickness. It can be assured that the sheet resistance of an absorbing layer to get a maximum absorption is $377{\Omega}/{\square}$, that the thickness of the absorbing layer dose not affect the spectral characteristics of absorption. It is also shown that the thickness of the active layer is not critical to the IR absorption. It can also be assured that the validation of this modeling is proved in comparison with the previous results from similar absorbing structures.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1991년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 22-24 Oct. 1991
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• pp.488-492
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• 1991

This paper deals with modeling and scheduling for flexible manufacturing systems(FMS). In modeling extended Petri nets are used to describe various and complex properties. To resolve multiple conflict without predefined properties, such as part selection, machine selection, rule-based scheduling method is introduced. This structure have a capability of on-line scheduling with systematic modeling description.

• 대한기계학회논문집A
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• 제21권8호
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• pp.1332-1338
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• 1997

In the case of the transfer function for the secondary path is dependent on time, the on-line method which can model it is continuously must be applied to the active noise control technique. And the adaptive random noise technique among the on-line methods is effective in the narrow-band control. In this method, the signal to noise ratio between random noise for modeling and primary noise is low. Therefore, the estimations of transfer function will be prone to inaccuracies and the convergence time will be too long. Such imperfections will have an influence upon the performance of an active noise controller. In this study, t enhance the signal to noise ratio, the on-line method that is combined the conventional adaptive random noise technique and the adaptive line enhancer, is proposed. By using proposed on-line method, a rigorous system identification and control of primary noise have been implemented.

• 한국생산제조학회지
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• 제8권3호
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• pp.42-51
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• 1999

An experimental modeling of cutting and structural dynamics and the on-line detection of malfunction process is substantial not only for the investigation of the static and dynamic characteristics of cutting process but also for the analytic realization of diagnostic systems. In this regard, We have discussed on the comparative assessment of two recursive time series modeling algorithms that can represent the machining process and detect the abnormal machining behaviors in precision round shape machining such as turning, drilling and boring in mold and die making. In this study, simulation and experimental work were performed to show the malfunctioned behaviors. For this purpose, two new recursive approach (REIVM, RLSM) were adopted fur the on-line system identification and monitoring of a machining process, we can apply these new algorithm in real process for the detection of abnormal machining behaviors such as chipping, chatter, wear and round shape lobe waviness.

• 제어로봇시스템학회논문지
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• 제10권10호
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• pp.878-886
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• 2004

Uncertainties are inevitable in robotic assembly in unstructured environment since it is difficult to construct fixtures to guide motions of robots. This paper proposes an augmented Petri net and an algorithm to adapt the assembly model on-line during actual assembly process. The augmented Petri net identifies events using force and position information simultaneously. Unmodeled contact states are identified and incorporated into the model on-line. The proposed method increases the level of intelligence of the robot system by enhancing the autonomy. The proposed method is evaluated by simulation and experiments with L-type peg-in-hole assembly using a two-arm robot system.

• 한국컴퓨터정보학회논문지
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• 제7권1호
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• pp.54-61
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• 2002

본 연구는 UML을 이용해 유스 케이스에 의한 순차 다이어그램을 도출하여 클래스 다이어그램을 만든 후 그 클래스 다이어그램에 의해서 XML 모델링과 데이터 모델링을 구현하고자 한다. XML 모델링을 위해 UML 클래스를 XML문서로 변환시키는 가이드라인을 제시하고, 제시한 방법에 따라 UML클래스를 XML DTD로 도출하는 예를 보일 것이며, 한편 데이터 모델링은 UML 클래스를 객체지향 데이터베이스로 변환시키기 위한 변환 방법을 제시하며, 제시한 변환 방법에 따라 구현 예를 보일 것이다.

• Journal of Power Electronics
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• 제14권3호
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• pp.572-579
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• 2014

As a non-linear time variant system, the four-quadrant line converter of an electric multiple unit (EMU) was expressed by linear time periodic functions near an operating point and modeled by a steady-state harmonic domain matrix. The components were then combined according to the circuit connection and relations of the feedback control loops to form a complete converter model. The proposed modeling method allows the study of the amplitude of harmonic impedances to explore harmonic coupling. Moreover, the proposed method helps provide a better design for the converter controllers, as well as solves the problem in coordination operation between the EMUs and the AC supply. On-site data from an actual $CRH_2$ high-speed train were used to validate the modeling principles presented in the paper.

• 대한전기학회논문지:전력기술부문A
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• 제48권6호
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• pp.699-703
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• 1999

It is known that the LDC(Line-Drop Compensator) becomes to lose the function of proper voltage regulation for its load currents due to the real and reactive power generated by DGS(Dispersed Generation System), when DGS is introduced into the power distribution system of which the voltage is controlled by LDC. Therefore, in that case, it is very difficult to regulate the distribution line voltage properly by using LDC. One possible solution for this problem is the real-time voltage regulation method which is to optimally regulate the sending-end voltage in real-time by collecting the real-time load data of each load data of each load section between measuring points and by calculating the optimal seding-end voltage value from them. For this, we must know the real-time load data of each load section. In this paper, a modeling method of representing a load section on high voltage line with DGSs as an equivalent lumped load is proposed for gaining the real-time load data. In addition a method of locating the measuring points is proposed. Then, these proposed methods are evaluated through computer simulations.

• 한국콘텐츠학회논문지
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• 제9권12호
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• pp.891-899
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• 2009

유아/초등학생용 UI design의 부재와 창의력 교육 서비스 시장에서 On-line과 Off-line상의 교육부분 모두를 만족시키고 창의력 개발을 극대화 시켜주는 교육프로그램과 컨텐츠가 요구되고 있다. 이러한 창의력(조형) 개발 교육 프로그램의 다양한 활용을 위해서 On-line과 Off-line상의 교육을 병행할 수 있는 컨텐츠와 교재/교구(이하:크레키즈 Cre-kids)의 개발이 필요하다. 크레키즈는 창의성 4요소(유창성, 융통성, 독창성, 정교성)를 증진시킬 수 있는 4가지 영역별로 나누어져있다. 4가지 영역은 (1)언어적 발상, (2)시각적 발상, (3)만들기 발상, (4)컴퓨터 발상으로 되어있다. 영역을 통하여 아이들에게 체계적으로 조형발상능력을 키워주며 4가지의 영역을 다시 유창성, 융통성, 독창성, 정교성 4사 분면으로 나누며 각각의 분면을 평가하고 이것을 지수로 나타낸다. 이것을 CDQ(Creativity Design Quotient) 라고 할 수 있으며 각 컨텐츠에 대한 평가 결과를 토대로 하여 조형 창의력 지수에 대한 연구가 가능 할 것이다.