• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1993년도 제2회 신약개발 연구발표회 초록집
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• pp.179-179
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• 1993

1. PS및 CP의 flux는 전류의 새기 및 donor의 약물농도에 비래하였다. 2. pH의 flux는 pH가 증가할수록 증가하였으나, CP(pKa=9.2)의 flux는 pH=2에서 최대치를 보였다. 이는 약물의 해리 정도와 H$^{＋}$이온의 mobility, 또 피부의 permselectivity의 balance에 의해 결정된 것으로 생각된다. 3. donor cell에 NaCl을 첨가하면 두 약물 공히, 그러나 특히 PS의 flux가 저하되었다. 이는 두 약물의 이온과 $Na^{＋}$의 mobility차이에 기인한다고 생각된다. 4. PS의 경우 taurodeoxycholate(TDC)같은 음이온을 donor cell에 공존시키면 flux가 감소하였다. 이는 PS와 TDC가 전기적으로 중성인 ion-pair complex를 형성함으로써 PS이온의 유효농도가 감소하기 때문으로 생각된다.

• 월간 기계설비
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• 통권6호
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• pp.93-98
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• 1990

• JSTS:Journal of Semiconductor Technology and Science
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• 제13권4호
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• pp.272-281
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• 2013

This paper presents low power frequency shift keying (FSK) transmitter using all digital PLL (ADPLL) for smart utility network (SUN). In order to operate at low-power and to integrate a small die area, the ADPLL is adopted in transmitter. The phase noise of the ADPLL is improved by using a fine resolution time to digital converter (TDC) and digitally controlled oscillator (DCO). The FSK transmitter is implemented in $0.18{\mu}m$ 1-poly 6-metal CMOS technology. The die area of the transmitter including ADPLL is $3.5mm^2$. The power consumption of the ADPLL is 12.43 mW. And, the power consumptions of the transmitter are 35.36 mW and 65.57 mW when the output power levels are -1.6 dBm and +12 dBm, respectively. Both of them are supplied by 1.8 V voltage source. The frequency resolution of the TDC is 2.7 ps. The effective DCO frequency resolution with the differential MOS varactor and sigma-delta modulator is 2.5 Hz. The phase noise of the ADPLL output at 1.8 GHz is -121.17 dBc/Hz with a 1 MHz offset.

• 한국방재학회:학술대회논문집
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• 한국방재학회 2008년도 정기총회 및 학술발표대회
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• pp.799-802
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• 2008

General behaviors based on hydraulic characteristics of natural streams and channels have been recently analyzed and developed via various numerical models. However in the states of natural hydraulics, an experimental research must be performed simultaneously with the mathematical analysis due to effects of hydraulic properties such as meander, sediment, and so on. In this study based on 2-D advection-dispersion equation, flow and tracer experiments were performed in the S-curved meandering laboratory channel with a rectangular cross-section. The channel was equipped with instrument carriages which was equipped with an auto-traversing system to be used with velocity measuring sensors throughout the depth and breadth of the flow field. To measure concentration distribution of the salt solution was adjusted to that of the flume water by adding methanol and a red dye (KMnO4) was added to aid the visualization of the tracer cloud, the tracer was instantaneously injected into the flow as a full-depth vertical line source by the instantaneous injector and the initial concentration of the tracer was 100,000 mg/l. The secondary current as well as the primary flow pattern was analyzed to investigate the flow distribution in the meandering channels. The velocity distribution of the primary flow for all cases skewed toward the inner bank at the first bend, and was almost symmetric at the crossovers, and then shifted toward the inner bank again at the next alternating bend. Thus, one can clearly notice that the maximum velocity occurs taking the shortest course along the channel, irrespective of the flow conditions. The result of the tracer tests shows that pollutant clouds are spreading following the maximum velocity lines in each cases with various mixing patterns like superposition, separation, and stagnation of pollutant clouds. Flow characteristics in each cases performed in this study can be compared with tracer dispersion characteristics with using evaluation of longitudinal and transverse dispersion coefficients(LDC, TDC). As expected, LDC and TDC in meandering parts have been evaluated with increasing distribution and straight parts have effected to evaluate minimum of LDC and TDC due to symmetric flow patterns and attenuations of secondary flow.

• 한국전자파학회논문지
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• 제30권1호
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• pp.60-69
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• 2019

본 논문에서는 전방 관측 특히, 곡선운동을 하는 차량용 전방 관측 역산란 합성 영상 형성에 대해 다룬다. 영상 형성을 위해 시간 영역 상관관계(time domain correlation: TDC) 기법이 사용되었으며, 차량의 전방 지면의 2D 영상을 얻는다. TDC는 공간변화 시스템에 대한 정합 필터링을 구현한 기법이므로 가우시안 잡음에 강건하다. 또한, 직선운동을 할 때의 영상과 곡선운동을 할 때의 영상에 대한 비교, 분석을 통해 곡선운동을 했을 때 영상의 엔트로피가 증가하는 대신 영상의 분해능이 향상되었음을 보인다.

• 제어로봇시스템학회논문지
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• 제17권1호
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• pp.1-5
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• 2011

The basic signals for electronic engine control are velocity and degree of the engine cam shaft. The CPS sensor used for this signal and magnetic pick-up type CPS sensor is more popular. It is very important thing analyze this signal correctly. If there are some mistakes at the analysis, like a noise, The engine do not working at the best status, it will generate some noise, emit exhaust fumes and waste more gases. In general way to analysis this signal, you use zero-level detector circuit and in order to reduce the error you must use another sensor like a TDC sensor. In this paper, We proposed the analysis method using electronics circuits for magnetic pick-up type CPS sensor. We designed Comparison level detector circuit, Differential circuit and Full-rectifier circuit for detected the Long tooth and Short tooth level correctly without another sensor. We expected it is useful for more reliable engine control.

• 대한기계학회논문집
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• 제17권5호
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• pp.1029-1040
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• 1993

이 논문에서는 잘 모르는 플랜트에 대하여 TDC를 위한 관측기를 설계하고, 이 관측기와 TDC제어기가 연결된 전체 계의 안정화에 대하여 해석한다. 그리고 이 관측 기와 TDC제어기를 DC서보 모터 시스템에 적용하여, 모터에 가해지는 외란과 내부의 매개변수 변동에 강힌한 재어기를 설계하고 그 성능을 실험한다.

• Journal of Computing Science and Engineering
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• 제10권4호
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• pp.111-117
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• 2016

An accurate approach for diagnosis of attention deficit hyperactivity disorder (ADHD) is presented in this paper. The presented technique efficiently classifies three subtypes of ADHD (ADHD-C, ADHD-H, ADHD-I) and typically developing control (TDC) by using only structural magnetic resonance imaging (MRI). The research examines structural MRI of the hippocampus from the ADHD-200 database. Each available MRI has been processed by a region-of-interest (ROI) to build a set of features for further analysis. The presented ADHD diagnostic approach unifies feature selection and classification techniques. The feature selection technique based on the proposed binary-coded genetic algorithm searches for an optimal subset of features extracted from the hippocampus. The classification technique uses a chosen optimal subset of features for accurate classification of three subtypes of ADHD and TDC. In this study, the famous Extreme Learning Machine is used as a classification technique. Experimental results clearly indicate that the presented BCGA-ELM (binary-coded genetic algorithm coupled with Extreme Learning Machine) efficiently classifies TDC and three subtypes of ADHD and outperforms existing techniques.

• 대한기계학회논문집A
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• 제21권12호
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• pp.2081-2089
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• 1997

Accurate positioning of the throttle valve of a gasoline engine is required to implement various systems such as traction control system(TCS), cruise control system and drive-by-wire system. In this research, position control system has been developed for the throttle actuator system that uses one throttle actuation for small volume and DC servo motor for fast response. In order to drive the DC motor, PWM signal generator and PWM amplifier were built and interfaced to the motor and controller. Also, time delay control(TDC) law has been used as a basic control algorithm. A method of varying the reference model of the TDC according to the size of change in target throttle angle is proposed here. The simulation and experimental results show that both overshoot prevention and fast response are achieved by the TDC technique with this variable reference model.

• 한국정밀공학회지
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• 제23권2호
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• pp.43-50
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• 2006

Recently, with rapid development of semiconductor and flat panel display, the manufacturing equipments are required to have large travel range, high productivity, and high accuracy. In this paper, an ultra precision decoupled dual servo (DDS) system is proposed to meet these requirements. And a control scheme for the DDS is studied. The proposed DDS consists of a $XY{\Theta}$ fine stage for handling work-pieces precisely and a XY coarse stage for large travel range. The fine stage consists of four voice coil motors (VCM) and air bearing guides. The coarse stage consists of linear motors and air bearing guides. The DDS is mechanically decoupled between coarse stage and fine stage. Therefore, both stages must be controlled independently and the performance of the DDS is mainly determined by the fine stage. For high performance tracking, the controller of fine stage consists of time delay control (TDC) and perturbation observer while the controller of coarse stage is TDC alone. With these individual controllers, two kinds of dual-servo control strategies are suggested: master-slave type and parallel type. By simulations and experiments, the performances of two dual-servo control strategies are compared.