• Imaging Science in Dentistry
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• 제44권2호
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• pp.165-169
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• 2014

An osteolytic lesion with a small central area of mineralization and sclerotic borders was discovered incidentally in the clivus on the cone-beam computed tomography (CBCT) of a 27-year-old male patient. This benign appearance indicated a primary differential diagnosis of non-aggressive lesions such as fibro-osseous lesions and arrested pneumatization. Further, on magnetic resonance imaging (MRI), the lesion showed a homogenously low T1 signal intensity with mild internal enhancement after post-gadolinium and a heterogeneous T2 signal intensity. These signal characteristics might be attributed to the fibrous tissues, chondroid matrix, calcific material, or cystic component of the lesion; thus, chondroblastoma and chondromyxoid fibroma were added to the differential diagnosis. Although this report was limited by the lack of final diagnosis and the patient lost to follow-up, the incidental skull base finding would be important for interpreting the entire volume of CBCT by a qualified oral and maxillofacial radiologist.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1998년도 추계종합학술대회 논문집
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• pp.783-786
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• 1998

We designed a 3.3 V, 400 Mbps IEEE-1394 physical layer transeiver on 0.6um 1P3M CMOS process. The transceiver drives a twisted pair cable of which differential impedance is 110 $\Omega$ so that differential amplitude reaches 200 mV at 400 Mbps and restores this small signal to rail-to-rail. Also, the transceiver arbitrates the interface among nodes on a bus configuration and supports both synchronous interface and asynchronous interface.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2002년도 하계종합학술대회 논문집(2)
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• pp.149-152
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• 2002

The performance of a 1-bit DAC depends on that of the analog circuits. The mixed SC-CT (switched capacitor-continuous time) architecture is an effective design methodology for the analog circuits. This paper Proposes a new buffer scheme for the 1-bit digital-to-analog subconverter and a new SF-DSC(smoothing filter and differential-to-sig le converter) which performs both the smoothing filter and the differential-to-single convertor simultaneously.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1999년도 추계종합학술대회 논문집
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• pp.967-970
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• 1999

A novel linear transconductor for low-voltage low-power signal processing is proposed. The transconductor consists of a pnp differential-pair and a npn differential-pair which are biased by local negative feedback. The simulation results show that the transcondcutor with transconductance of 50 $mutextrm{s}$ has a linearity error of 0.05% and the power dissipation is 2.44 ㎽ over an input linear range from -2V to +2V at supply voltage $\pm$3V.

• 산업기술연구
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• 제18권
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• pp.439-442
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• 1998

In this paper, we firstly suggested C&D (Common mode and Differential mode) model for the representation of a stereophonic signal. Then a measure of stereophonic channel separability is defined as the ratio of differential mode energy to total energy in frequency domain. After that, a new channel separability enhancement scheme is proposed by the control of common mode rejection. Finally, some experimental results are presented in order to verify our scheme.

• 한국전자통신학회논문지
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• 제10권5호
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• pp.565-570
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• 2015

확산 스펙트럼 통신은 낮은 도청확률과 작은 잡음 채널의 영향 때문에 많은 시스템에서 사용이 증가하고 있다. 기존의 디지털 확산 스펙트럼 시스템의 한계 중 하나는 동기 코드 확산에 대한 필요성이다. 카오스 통신 시스템은 동기 없이 구현 할 수 있고 보안성도 우수하며 간단한 송수신기 구조로 디지털 확산 스펙트럼 통신에 많이 사용하고 있다. 본 논문에서는 카오스 신호를 디지털 통신시스템에 사용하기 위해 디지털 변복조의 반송파 대신 사용하였으며 여러 가지의 카오스 변조 방식들 중에서 차동 CSK(Differential Chaos Shift Keying) 사용한다. DCSK 복조기는 카오스 신호 위상을 복구 할 필요 없이 데이터를 감지하기 때문에 효율적이다. 또한 Matlab/Simulink를 이용하여 DCSK 변조기 및 복조기의 설계하고 성능을 분석하고 송신신호의 수신 신호를 비교하여 송수신 신호가 같은 것을 확인하고 확산 인자에 따른 BER의 성능을 평가한다.

• 한국전자통신학회논문지
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• 제14권6호
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• pp.1061-1068
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• 2019

협력 네트워크는 송신기로부터 수신기로 신호를 전송할 때 여러 중계기를 이용하여 신호를 전송하고 수신기에서 이 신호를 결합하여 복조함으로써 통신성능 향상과 데이터 전송률을 높이는 장점을 제공한다. 일반적으로 송신기에서 수신기로 신호를 전송할 때 중계기가 송신기로부터 수신된 신호를 증폭/재변조 후 수신기로 보내는 반복적인 신호 전송형태가 널리 사용된다. 본 논문에서는 두 가지 신호전송 방식을 혼합하여 신호를 전송하는 협력 네트워크에서의 성능을 분석한다. 즉, 송신기와 중계기사이에서는 일반 변조방식을 사용하고, 중계기와 수신기 사이에서는 공간 시간 코드 방식을 적용한다. 변조방식은 시스템의 복잡도를 줄이기 위해 채널상태정보를 이용하지 않는 차등변조 방식을 이용한다. 다양한 개수의 중계기가 있을 경우에 대한 성능을 비트오류율을 이용하여 분석하며, 송신기와 중계기 및 중계기와 수신기 사이에서 서로 다른 세기로 신호를 보낼 때의 성능을 비교한다. 또한 다양한 신호세기 및 중계기의 개수를 동시에 고려한 성능에 대해서도 논의한다.

• International Journal of Advanced Culture Technology
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• 제6권3호
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• pp.187-192
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• 2018

Permeate alteration technique is compounded the steeple sway-tuner status of the gleam-differential realization level (GDRL) on the permeate realization morph. The realization level condition by the permeate realization morph system is associated with the sway-tuner system. As to search a dot of the dot situation, we are gained of the permeate value with character-dot by the output signal. The concept of realization level is composed the reference of gleam-differential level for alteration signal by the permeate tuner morph. Moreover displaying a steeple alteration of the GDRL of the average in terms of the sway-tuner morph, and permeate dot tuner that was the a permeate value of the far alteration of the $Per-rm-FA-{\alpha}_{AVG}$ with $14.63{\pm}1.23units$, that was the a permeate value of the convenient alteration of the $Per-rm-CO-{\alpha}_{AVG}$ with $8.28{\pm}0.97units$, that was the a permeate value of the flank alteration of the $Per-rm-FL-{\alpha}_{AVG}$ with $3.28{\pm}0.58units$, that was the a permeate value of the vicinage alteration of the $Per-rm-VI-{\alpha}_{AVG}$ with $0.51{\pm}0.10units$. The sway tuner will be to evaluate at the steeple ability of the sway-tuner morph with character-dot by the permeate realization level on the GDRL that is displayed the gleam-differential morph by the realization level system. Sway realization system will be possible to control of a morph by the special signal and to use a permeate data of sway tuner level.

• 한국군사과학기술학회지
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• 제9권1호
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• pp.89-98
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• 2006

This paper describes signal attenuation characteristics as splicing the output on LVDT for stability and reliability of switching mechanism, which is developed to use common signal between FLCC and EDFLCC, on T-50 aircraft. The method of test is classified a Pspice simulation and an actual hardware evaluation. The difference of error margin for two methods is 10times, the latter higher. The result in this experiment shows that the signal attenuation as splicing the output on LVDT doesn't affect and the static error margin is 53% for develope the EDFLCC.

• 대한전자공학회논문지
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• 제23권5호
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• pp.597-604
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• 1986

This paper describes various mismatch phenomena in differential pulse code modulation (DPCM) coding, such as the mismatch effects of probability density functin(pdf), signal variance, and correlation. At a high transmission rate(i.e., above 32 kbits/s), the performance of DPCM can be improved by matching the pdf shape between the input signal and the quantizer. However, the same gain cannot be obtained at a lower transmission rate. Also, it is shown that the gamma quantizer is realtively robust to the variation of pdf shaper and signal variance. Moreover, as the transmission rate increases, the performance of DPCM for the input signal with large variance is worse than that of DPCM for the signal with small variance due to the increase of overload noise. According to our simuladiton results, the mismatch effects of pdf shape and variance appear to yield more degradatin than that of correlation in a DPCM system.