• 정보학연구
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• 제4권4호
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• pp.51-63
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• 2001

잉여수계(Residue Number System)는 각 모듈러스에 자리올림수의 전달이 필요 없고, 병렬 구조를 이루므로, 디지털 신호처리 및 신경망 처리기와 같은 전용 프로세서 설계에서 사용된다. 그러나, 크기 비교 및 부호 검출시에 혼합기수변환(Mixed Radix Conversion)이 요구되며, 이는 전체 연산 속도를 저해하는 요인이 된다. 그러므로 본 논문에서는 혼합기수 변환의 속도를 향상시키기 위하여 잉여수 분할 방법을 개선한 혼합기수변환기를 설계하였다. 설계된 변환기는 기존의 변환기에 비하여 연산기의 크기는 증가하지만 연산시간은 최대 2배가 향상되었다.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2012년도 추계학술대회 논문집
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• pp.5-6
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• 2012

In this paper, a simplified maximum power point tracking technique for the solar charger is presented. Main advantages of the proposed charger include low cost and optimized charge time. The maximum power point tracking method is used to deliver the maximum power from PV array to the battery thereby reducing the charge time. Moreover, the proposed technique which tracks the maximum power point by adjusting output current helps reduce the quantity of required number of sensors for the charger. The experimental protype was implemented by using an 80W PV array, a buck converter and a digital signal processor to verify the feasibility of the proposed method.

• 전자공학회논문지A
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• 제33A권7호
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• pp.121-126
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• 1996

In this paper an MMIC VCO which can be used in a double conversion TV tuner is designed, fabricated and measured. The VCO is designed using the small signal method and fabricated using ETRI GaAs MMIC foundry. The 3x200$\mu$m gate width MESFET with 1$\mu$m gate length is used for an active device and MIM capacitors, spiral inductors, thin film resitors are used as passive elements. The VCO has output power of 10.95dBm at 1955 MHz with 5V bias voltage and 4V tuning voltage. The oscillation frequency change form 1947 MHz to 1964 MHz is obtaine dby an external varactor diode connected to the gate with a tuning voltage from 0 V to 6V.

• 세라미스트
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• 제23권1호
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• pp.38-53
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• 2020

Magnetoelectric (ME) composites composed of magnetostrictive and piezoelectric materials derive interfacial coupling of magnetoelectric conversion between magnetic and electric properties, thus enabling to detect ultra-low magnetic field. To improve the performance of ME composite sensors, various research teams have explored adopting highly efficient magnetostrictive and piezoelectric phases, tailoring of device geometry/structure, and developing signal process technique. As a result, latest ME composites have achieved not only outstanding ME conversion coefficient but also sensing of ultra-low magnetic field below 1pT. This article reviews the recent research trend of ME composites for sensing of ultra-low magnetic field.

• Journal of information and communication convergence engineering
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• 제7권4호
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• pp.561-564
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• 2009

A cryptographic dongle, which is capable of transmitting encrypted voice signals over the CDMA/GSM voice channel, was designed and implemented. The dongle used PIC microcontroller for signals processing including analog to digital conversion and digital to analog conversion, encryption and communicating with the smart phone. A smart phone was used to provide power to the dongle as well as passing the encrypted speech to the smart phone which then transmits the signal to the network. A number of tests were conducted to check the efficiency of the dongle, the firmware programming, the encryption algorithms, and the secret key management system, the interface between the smart phone and the dongle and the noise level.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.II
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• pp.863-864
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• 2005

In recent years, we use overdriving scheme to improve the response time of the liquid crystal. Since conventional overdriving scheme uses memory to perform ideal processing, it is desired to reduce system cost by decreasing the data stored in these SDRAMs. As a general compression method, quantization, sub-sampling and Block Truncation Coding ( BTC ) are used, which process data in block base and cause block effect. So we proposed new data compression method by color space conversion. Because this method compresses luminance and chrominance signal by different ratio, it can efficiently reduce error of block effect in decompression image.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2002년도 ITC-CSCC -2
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• pp.1046-1049
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• 2002

In this paper, a sub-harmonic dual-gate FET mixer for IMT-2000 base-station was designed by using single-gate FET cascode structure and driven by the second order harmonic component of LO signal. The dual-gate FET mixer has the characteristic of high conversion gain and good isolation between ports. Sub-harmonic mixing is frequently used to extend RF bandwidth for fixed LO frequency or to make LO frequency lower. Furthermore, the LO-to-RF isolation characteristic of a sub-harmonic mixer is better than that of a fundamental mixer because the frequency separation between the RE and LO frequency is large. As RF power is -30dBm and LO power is 0dBm, the designed mixer shows the -47.17dBm LO-to-RF leakage power level, 10dB conversion gain, -0.5dBm OIP3, -10.5dBm IIP3 and -1dBm 1dB gain compression point.

• 방송공학회논문지
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• 제16권5호
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• pp.824-833
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• 2011

In this paper, using the Rec. ITU-R P.1546 explaining a propagation prediction model in the VHF and UHF bands, we propose the analytical methodology for calculating the service distance and field strength for analogue and digital TV receivers. From the derived formulation of the receiver field strength, some computation results are presented and discussed in terms of the equivalent level of service caused by analogue to digital TV conversion. The suggested method is also applicable to the analysis of frequency coordination or compatibility from unwanted signal in VHF and UHF bands.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1999년도 추계종합학술대회 논문집
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• pp.263-266
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• 1999

In this work, a A/D converter is implemented to obtain 8bit resolution at a conversion rate of 10MS/s for video applications. This architecture is proposed using the Pipelined architecture for high speed conversion rate and the Successive - Approximation architecture for low power consumption, and consists of two identical stages that consist of sample/hold circuit, low power comparator, voltage reference circuit and MDAC of binary weighted capacitor array. Proposed A/D converter is designed using 0.25${\mu}{\textrm}{m}$ CMOS technology The SNR is 80㏈ at a sampling rate of 10MHz with 1.95MHz sine input signal. When an 8bit 10MS/s A/D converter is simulated, the Differential Nonlinearity / Integral Nonlinearity (DNL/ INL) error are $\pm$0.5 / $\pm$2 LSB, respectively. The power consumption is 13㎽ at 10MS/s.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2006년도 전력전자학술대회 논문집
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• pp.222-224
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• 2006

To improve the drawback of LCMPPT(Limit Cycle Maximum Power Point Tracking) controller of the existing two power conversion stages, an advanced MPPT scheme of single power conversion stage is proposed in this paper. This topology is faster on the control speed by means of current control method and the system configuration is simpler. The Authors produce a battery charger by using a cost effective one-chip processor (PIC16F877A) and evaluate another application on the basis of simulation. As a result, the proposed new LCMPPT algorithm is confirmed to be stable and useful.