• The Journal of Korean Institute of Communications and Information Sciences
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• v.25 no.12B
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• pp.2052-2059
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• 2000

Digital IF(Intermediate Frequency) 처리단과 같은 고속과 저전력을 요구하는 필터에서 덧셈기만을 사용하여 CSD(Canonical Signed Digit)형의 필터계수들을 구현하는 구조가 널리 연구되고 있다. 본 논문에서는 선형위상 FIR(Finite Impulse Response) 필터의 CSD형 필터계수들을 최소의 덧셈으로 구현할 수 있는 아키텍처를 제안한다. 1과 -1로 이루어진 필터계수 표에서 공통패턴을 공유함으로서 덧셈의 수를 줄이는 방법이 이미 연구되었다. 본 논문은 비트 shift, 비트 add, 비트 반전을 통하여 인공의 공통패턴을 만들어서 이미 존재하는 공통패턴에 합류시킴으로서 덧셈의 수를 더욱 줄일 수 있는 방법을 제안한다. CDMA 이동통신 단말기의 IF단에 사용되는 사양의 디지털 필터를 73탭의 CSD형 계수로 구현하여 9.2%의 덧셈 감소의 효과가 있음을 보였다.

• Journal of The Korean Astronomical Society
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• v.29 no.spc1
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• pp.379-380
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• 1996

We have constructed a near-infrared imaging camera which is attached to the prime focus of 105cm Schmidt telescope at Kiso Observatory. The camera is equipped with a 1040$\times$1040 PtSi CSD array developed by Mitsubishi Electric Co. The combination of Kiso Schmidt and the array gives a wide field of view of 18.4'$\times$18.4' with a reasonable spatial resolution of 1.06' /pixel. The system performances of the camera have been evaluated through laboratory and observational tests. Low noise, good cosmetics(no defect pixels), and good stability of the camera system show an excellent performance for astronomical use.

• Proceedings of the Acoustical Society of Korea Conference
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• spring
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• pp.52-55
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• 1999

다중 전송율(16, 24, 32, 40kbps)을 제공하는 G.726 부호화기는 ADPCM (Adaptive Differential Pulse Code Modulation) 부호화법을 사용한다. 본논문에서는 G.726 ADPCM 알고리즘을 C&S Technology에서 개발한 음성 신호 처리를 위한 범용 DSP인 CSD17C00A 칩을 이용하여 실시간 응용이 가능하도록 구현하였다. G.726에 대한 양방향 평가는 Codec Loopback test을 통해 수행되었으며, W-T에서 제공한 테스트 절차에 따라 평가되었다. 본 논문에서 구현된 G.726 부호화기는 평균 11 MIPS의 계산 속도를 갖고, 프로그램 메모리 크기는 2.8K Words이고, 데이터 메모리 크기는 550 Words 를 필요로 하였다.

• Proceedings of the Acoustical Society of Korea Conference
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• 1998.08a
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• pp.165-168
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• 1998

제안하고 있는 CSD17C00 chip은 C&S technology에서 개발한 것으로, 음성 신호 처리를 위해 범용으로 구현되었으며, 16 bit 40 MIPS DSP group OAK DSP Core를 포함, 이에 Miscellaneous Logic, Serial Port, Host Interface, Timer, Compander 의 5가지 Peripherals 과 범용 I/O Ports 로 설계되었다. 1차적으로 CSD17C00 Chip 의 성능을 점검하였다. 그 결과, 응용 프로그램은 28MIPS의 계산속도를 갖으며, 프로그램 ROM 크기는 8.85KWords 이고, 10KWords 의 데이터 ROM 과 4KWords 데이터 RAM을 필요로 한다. CSD17C00 CHIP은 멀티미디어 통신용 VOCODER 개발을 위한 범용성을 갖추고 있으며, VOCODER 용 S/W 개발 환경 및 H/W 구조가 여타 범용 DSP에 비해편의성고 K합리성을 제공하도록 설계되어 있다. 따라서, 이를 이용한다면, 멀티 미디어 통신용 VOCODER, INTERNET PHONE CO-PROCESSOR, DIGITAL RECODER, MPEG AUDIO ENCODER & DECODER 등 다양한 제품으로의 응용이 가능할 것으로 전망된다.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2009.05a
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• pp.409-412
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• 2009

A study is made to put forward the new method of continuous-shear drawing (CSD), and investigate deformation behavior and microstructure evolution of aluminum alloy with a comparison of equal-channel angular (ECA) drawing. In contrast to ECA drawing, the die for CSD deformation can impart an additional strain to the workpiece since the diameter of the exit channel is narrower than that of its entrance channel. Although no significant crack occurs in all conditions during deformation, the sample deformed via CSD method showed better surface quality as compared to ECA drawing. This is mainly ascribed to the fact that the sample is significantly bent rather than sheared when deforming through ECA drawing.

• Proceedings of the IEEK Conference
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• 2006.06a
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• pp.511-512
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• 2006

Three stage(CIC-FIR-FIR) decimation filter in delta-sigma A/D converter for audio is designed. A canonical signed digit(CSD) code method is used to minimize area of multipliers. This filter is designed in 0.25um CMOS process and incorporates $1.36\;mm^2$ of active area. Measured results show that this decimation filter is suitable for digital audio A/D converters.

• Proceedings of the KIPE Conference
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• 2000.07a
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• pp.111-114
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• 2000

Harmonics and fundamental reactive power of nonlinear loads in serious unbalanced power condition are compensated by current synchronous detection(CSD) theory which is also acceptable for single phase power system, but the CSD theory is not suitable any more in case of controlled independently harmonics and reactive component. Therefore a new algorithm the extended current synchronous detection (ECSD)theory for a three phase active power filter based on decomposition of fundamental reactive distorted components is proposed in this paper. The proposed ECSD theory is simulated and tested comparison with a few power theories under asymmtrical condition in power system.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.42 no.2 s.302
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• pp.143-150
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• 2005

This paper proposes a new $radix-2^4$ FFT algorithm and an efficient pipeline architecture based on this new algorithm for OFDM systems. The pipeline architecture based on the new algorithm has the same number of multipliers as that of the $radix-2^2$ algorithm. However, the multiplier complexity could be reduced by more than $30\%$ by replacing one half of the programmable complex multipliers by the newly proposed CSD constant complex multipliers. From synthesis simulations of a standard 0.35um CMOS Samsung process, a proposed CSD constant complex multiplier achieved more than $60\%$ area efficiency when compared with the conventional programmable complex multiplier. This promoted efficiency can be used for the design of a long length FFT processor in wireless OFDM applications which needs more power and area efficiency.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.11 no.1
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• pp.91-99
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• 1999

Vapor-liquid equilibrium apparatus is designed and set up. The equilibrium data of two binary systems, HFC-32/143a and HFC-143a/134a, are measured. Fifteen equilibrium data for HFC-32/143a and HFC-143a/134a systems are measured over the temperature range 263.15~283.15K at 10K interval and the composition range 0.10~0.80, respectively. And vapor-liquid equilibrium data are calculated using equation of state and correlation of activity coefficient and compared with the present data. Equation of state is used CSD and RKS equations and correlation of activity coefficient is used Margules' and Van Ness and Abbott's correlations. Real behavior of HFC-32/143a system has very large deviation with Raoult's rule which is ideal behavior. But real behavior of HFC-143a/134a system is similar to ideal behavior. The calculated data from CSD equation are compared with the data in the open literatures and the calculated data from REFPROP. In the results for REFPROP, the relative deviations of bubble point pressure for HFC-32/143a system are within -2.16~0.84% for CSD equation and within -0.20~1.10% for RKS equation. And the relative deviations of bubble point pressure for HFC-143a/134a system are within -0.45~0.12% and -0.20~2.8% for CSD and RKS equations, respectively.

• Journal of the Korean Society of Child Welfare
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• no.53
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• pp.77-104
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• 2016

The purpose of this study was to examine the relationship between mothers' smartphone dependency(MSD) and their children's problem behavior and how children's smartphone dependency(CSD) mediates this relationship. A survey was conducted in the Seoul and Gyeonggi of 300 mothers having children from two to six years old. The results showed that MSD was directly related to both CSD and children's problem behavior, and in particular, had greater effects than CSD on children's problem behavior. CSD was found to mediate the relationship between MSD and children's problem behavior. The results suggest that mothers and their children should be provided with education on the proper usage of smartphone to prevent problem behavior in children, and that the development of preventive programs for smartphone addiction is needed.