• 한국주조공학회지
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• 제14권6호
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• pp.576-589
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• 1994

Water modeling experiments and computer simulation for the predictions of defects of die castings are very important to produce high quality castings with less cost. The relation between the variable air vent system and the characteristics of the fluid flow in the die cavity is studied by using water modeling tests, which give ideas on reasonable designing of die cavity, vent arrangement and gating system. In order to test the water modeling, injection is done by using water containing NaCl. Flow behaviors in cavities are visualized by high speed camera and video tape recorder, and local filling time is measured with electrode sensors. Special attention is paid to the configuration of die cavity. Simulated results by computer are examined and compared with the results of water modeling experiments. There are close correlations between the simulated results and water modeling ones.

• Journal of information and communication convergence engineering
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• 제9권6호
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• pp.729-732
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• 2011

Power consumption during testing System-On-Chip (SOC) is becoming increasingly important as the IP core increases in SOC. We present a new algorithm to reduce the scan-in power using the modified scan latch reordering and clock gating. We apply scan latch reordering technique for minimizing the hamming distance in scan vectors. Also, during scan latch reordering, the don't care inputs in scan vectors are assigned for low power. Also, we apply the clock gated scan cells. Experimental results for ISCAS 89 benchmark circuits show that reduced low power scan testing can be achieved in all cases.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2001년도 Proceedings ICPE 01 2001 International Conference on Power Electronics
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• pp.126-131
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• 2001

This paper deals with implementation of inverter systems for DC power regeneration, which can regenerate the excessive DC power from DC bus line to AC supply in substations for traction systems. From the viewpoint of both power capacity and switching losses, a three-phase square-wave inverter system is adopted. To control the regenerated power, the magnitude and phase of fundamental output voltages should be appropriately controlled in spite of the variation of input DC voltage. Inverters are operated with modified a-conduction mode to fix the potential of each arm. The overall system consists of the line-to-line voltage and line current sensors, an actual power calculator using d-q transformation method, a complex power controller with PI control scheme, a gating signal generator for modified $\alpha-conduction\;mode\;with\;\delta\;and\;\alpha$, a DPLL for frequency followup, and power circuit.

• 한국통신학회논문지
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• 제22권6호
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• pp.1185-1194
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• 1997

It is necessary to control the frame memory to capture, edit and display images. This paper presents the free-scale image capture processor size of which is user-defined, compared to the conventional image capture processor size of which is fixed 1/2, 1/4 and full size. User-defined scale data is fed into this system, which generates the gating pulses and gates the inputted image data. This system also controls the 4M DRAM instead of frame meamory. And stored gated image data are displayed on the TV monitor. We designed the scalable image capture parts and DRAM controller with ACTEL FPGAs, simulated the circuits with Viewlogic and fusing ACTEL A1020B chips. We confirmed the whole operation with beadboard which composed of "Philips TV Chipset" and designed FPGA chips.PGA chips.

• 한국지능시스템학회논문지
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• 제11권5호
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• pp.395-399
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• 2001

이 논문은 학습을 통해 관측 데이터로부터 퍼지 추론 모듈을 생성할 수 있는 적응 능력을 갖는 모듈화 퍼지추론 시스템을 제안한다. 제안한 시스템은 TS 퍼지모델과 모듈화 신경회로망의 구조적 유사성을 기초로 한다. 학습과정은 새로운 퍼지추론 모듈의 생성과 모듈 파라미터의 갱신으로 구성된다. 퍼지추론 모듈은 국부모델망과 퍼지 게이팅망으로 구성된다. 제안한 시스템의 파라미터들은 표준 LMS 알고리즘을 이용하여 최적화된다. 제안한 시스템의 성능은 비선형 동적 시스템 적응제어에의 응용을 통해서 입증된다.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2014년도 춘계학술대회
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• pp.833-835
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• 2014

본 연구에서는 호흡동조방사선치료(Respiratory Gating Radiation Therapy, RGRT)에서 매우 중요한 요소 중에 하나인 호흡의 안정성을 효과적으로 향상 시킬 수 있는 호흡연습장치(respiratory training system)를 개발하였다. 개발한 호흡연습장치는 개인고유의 호흡주기를 적용하여 환자에게 편안한 호흡유도를 제공한다. 충분한 연습시간을 부여하기 위해 언제 어디서나 쉽고 간편하게 연습 할 수 있도록 휴대형 기기에 모듈화 시켰으며, 이를 환자에게 제공함으로써 호흡동조방사선치료의 효율성과 정확성을 높이고자 했다. 호흡연습장치를 사용했을 때 호흡의 규칙성, 안정성, 지속성 향상 정도를 알아보기 위해 5명을 대상으로 실험을 진행 하고자 한다. 개인이 자유롭게 호흡하는 '자유호흡(free breathing)' 개인고유 호흡주기를 적용하여 시청각 프로그램을 통해 호흡을 유도하는 '모니터호흡(guide breathing)' 호흡연습 후 시청각 프로그램 없이 호흡하는 '예측호흡(predict breathing)' 3가지 호흡법의 데이터를 이용하여 호흡주기(period)와 호흡깊이(amplitude) 및 호흡패턴(Area)의 변화를 정량적으로 분석함으로써 휴대형 호흡연습장치의 유용성을 평가하고자 한다.

• 한국자동차공학회논문집
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• 제22권7호
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• pp.107-116
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• 2014

This paper presents camera-based road surface marking detection methods suited to sensor fusion-based positioning system that consists of low-cost GPS (Global Positioning System), INS (Inertial Navigation System), EDM (Extended Digital Map), and vision system. The proposed vision system consists of two parts: lane marking detection and RSM (Road Surface Marking) detection. The lane marking detection provides ROIs (Region of Interest) that are highly likely to contain RSM. The RSM detection generates candidates in the regions and classifies their types. The proposed system focuses on detecting RSM without false detections and performing real time operation. In order to ensure real time operation, the gating varies for lane marking detection and changes detection methods according to the FSM (Finite State Machine) about the driving situation. Also, a single template matching is used to extract features for both lane marking detection and RSM detection, and it is efficiently implemented by horizontal integral image. Further, multiple step verification is performed to minimize false detections.

• IMMUNE NETWORK
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• 제9권6호
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• pp.243-247
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• 2009

In this study, we report the development of a new dual reporter vector system for the analysis of promoter activity. This system employs green fluorescence emitting protein, EGFP, as a reporter, and uses red fluorescence emitting protein, DsRed, as a transfection control in a single vector. The expression of those two proteins can be readily detected via flow cytometry in a single analysis, with no need for any further manipulation after transfection. As this system allows for the simultaneous detection of both the control and reporter proteins in the same cells, only transfected cells which express the control protein, DsRed, can be subjected to promoter activity analysis, via the gating out of all un-transfected cells. This results in a dramatic increase in the promoter activity detection sensitivity. This novel reporter vector system should prove to be a simple and efficient method for the analysis of promoter activity.

• 대한기계학회논문집A
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• 제25권10호
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• pp.1575-1582
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• 2001

Injection molding is widely used in producing various plastic parts due to its high productivity, and the demand for injection molded products with high precision is increasing. To achieve successful product quality and precision, the design of gating and runner system in injection mold is very important because it influences the melt flow into the cavity. Some deflects, such as weld lines and overpacking, can be effectively controlled with proper selection of gate locations. In the present study, the design of gate locations in injection molding of a dashboard fur automobiles was carried out with CAMP mold, a PC-based simulation system for injection molding. A dummy runner system was developed to simulate a runner system in order to increase the efficiency of the analysis procedure. The numbers and locations of gates were iteratively determined in the present investigation. In this procedure, an acceptable design was obtained in terms of reducing the maximum pressure and clamping force.

• Journal of Power Electronics
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• 제8권4호
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• pp.332-344
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• 2008

High frequency AC (HFAC) power distribution systems delivering power through a high frequency AC link with sinusoidal voltage have the advantages of simple structure and high efficiency. In a multiple module system, where multiple resonant inverters are paralleled to the high frequency AC bus through connection inductors, it is necessary for the output voltage phase angles of the inverters be controlled so that the circulating current among the inverters be minimized. However, the phase angle of the resonant inverters output voltage can not be controlled with conventional phase shift modulation or pulse width modulation. The phase angle is a function of both the phase of the gating signals and the impedance of the resonant tank. In this paper, we proposed a pulse phase modulation (PPM) concept for the resonant inverters, so that the phase angle of the output voltage can be regulated. The PPM can be used to minimize the circulating current between the resonant inverters. The mechanisms of the phase angle control and the PPM were explained. The small signal model of a PPM controlled half-bridge resonant inverter was analyzed. The concept was verified in a half bridge resonant inverter with a series-parallel resonant tank. An HFAC power distribution system with two resonant inverters connected in parallel to a 500kHz, 28V AC bus was presented to demonstrate the applicability of the concept in a high frequency power distribution system.