• Proceedings of the Optical Society of Korea Conference
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• 2001.02a
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• pp.160-161
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• 2001

APD(avalanche photo diode)는 수광된 빛에 의해 생성된 캐리어를 강한 역바이어스 전압(40 ～ 400V)으로 가속시켜 avalanche 증배를 일으켜 큰 current를 얻을 수 있도록 제작된 소자이다. APD는 P-N 포토 다이오드에 비하여 수십～수백배의 높은 반응도(responsivity)를 얻을 수 있으며 응답 시간이 매우 짧다는 장점이 있는 반면 불규칙한 전류에 의해 만들어지는 내부 잡음 레벨이 높으며 온도에 민감하다는 단점을 갖고 있다. (중략)

• Journal of Digital Convergence
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• v.13 no.12
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• pp.259-268
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• 2015

People with auditory processing disorders(APD) do not exactly understand what they hear with normal hearing levels because of difficulties in the processing of auditory information in auditory nervous system. The purposes of this study are to investigate intervention strategies suggested by current literatures and to develop a guide map for APD intervention. The problem based intervention strategies are customized to the specific deficits of a subtype of Buffalo model and Bellis/Ferre model and general intervention strategies are recommended with compensatory strategy, auditory training, environmental modification and so on. Multidisciplinary team should determine and provide various intervention strategies to improve auditory capabilities of a child with APD intensively and persistently. APD intervention guide map is organized with four steps. It helps clinicians and teachers related with the intervention of APD find appropriate intervention strategies and process in order to reduce difficulties of a child with APD and a suspected APD.

• Journal of the East Asian Society of Dietary Life
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• v.21 no.6
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• pp.871-876
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• 2011

In the present study, we investigated the compositions, antioxidant activities and anti-tumor effects of Artemisia princeps Pampanini (APD) as well as blanched leaves (CNBD) and dried leaves (CND) from Cirsium setidens Nakai on HepG2 cells. Water and ash contents were increased in CND. Protein and lipid contents were increased in CNBD. K, Ca, Mg, Fe and Cu contents of CND were higher than those of CNDB and APD. P contents was significantly decreased in CND. Yields of CND was reached high levels, but TPC, TFC, acacetin, apigenin, cynarin contents, and antioxidant activity were higher in APD. Viability of HepG2 liver cells was significantly decreased in APD. Therefore, extracts of APD are more effective preventing the liver cancer than extracts of CND and CNBD.

• Proceedings of the IEEK Conference
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• 2007.07a
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• pp.435-436
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• 2007

In this paper, we have been developed the software in order to ostinato for spill over for TV broadcasting signals between Korea and Japan and analyzed those signals using APD curve. In Busan, we have been measured channel of Japan TV broadcasting signals during 9 months from February 2006 to October 2006. That system has been controled and translated the measured data to remote-control place. Finally it has computation and compared in the APD curve using ITU-R P.1546.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.22 no.3
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• pp.539-546
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• 1997

In this paper, we proposed a new mehtod to analyze the performance degradation by timing jitters in the APD (avalanche photodiode) receivers of intensity modulation/direct detection digital optical communication systems where raised cosine pulse-shaping filters are used to reduce the effect of noise while minimizing intersymbol interferences. The proposed analytical method is an extension of an analytical method we have already developed for pin diode receivers, and incorporates the effects of APD's multiplication factor and resulting shot noise. Using the proposed analytical method, we derive an approximated power penalty due to timing jitters based on an assumption of Gaussian distribution for timing jitters, and compare with that of the conventional analytical method. The results obtained from the proposed analytical method show that conventional analytical methods underestimate the influence of timing jitters on the reciver performance. The results also show that APD's multiplication factor which optimizes receiver sensitivity is smaller than that obtained by the conventional analytical method.

• Journal of the Korean Society of Clothing and Textiles
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• v.46 no.5
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• pp.723-740
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• 2022

This study aimed to develop an Arduino-based garment pressure device (APD) on the basis of using Single-Tact sensor by suggesting the reliable clothing pressure range and coefficient of selected sensors through the APD calibration process. Once the APD was validated, the pressure of the experimental men's lower body compression wears was measured using the APD and was compared to the pressure measured using the existing air-pack type pressure meter. The subjects were one mannequin and eight men in their 20's, and the trial compression wears were calf sleeves and pants. Clothing pressures were measured in hip, mid-thigh, calf, and ankle. In terms of the 99% confidence level, the experimental clothing pressure measured at the designated measuring points using the APD was considered identical to the one measured using an existing clothing pressure meter. Therefore, on the basis of the experiment results, this study demonstrated that the APD is as reliable as the existing clothing pressure meter within the pressure ranges of 0.54-16.79 kPa and 0.18-25.47 kPa as provided by the SingleTact sensor supplier's data on the basis of using an external ADC (Analog to Digital Converter) module.

• Journal of Korean Neurosurgical Society
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• v.47 no.1
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• pp.1-6
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• 2010

Objective: On the basis of preoperative computed tomography (CT) scans, we studied the change of the size of anterior primary division (APD) of the L5 spinal root in the presence of foraminal/extraforaminal entrapment of the L5 spinal root. Methods: Two independent radiologists retrospectively reviewed the preoperative CT scans of 27 patients treated surgically and compared the sizes of the APDs on bilateral L5 spinal roots. If one side APO size was larger than the other side APD size, it was described as left or right "dominancy" and regarded this as "consensus (C)" in case that there was a consensus between the larger APD and the location of sciatica, and regarded as "non-consensus (NC)" in case that there was not a consensus. Oswestry Disability Index (ODI) scores were used for preoperative and postoperative evaluation. Results: On CT scans, twenty-one (77%) of 27 patients were the consensus group (APD swelling) and 6 (22%) were a non-consensus group (APD no swelling). In 9 patients with acute foraminal disc herniations, asymmetric enlargement of the APD on L5 spinal root was detected in all cases (100%) and detected in 11 (64%) of 17 patients with stenosis. Preoperative ODI score was 75-93 (mean 83) and postoperative 001 scores were improved to 13-36 (mean 21). The mean follow-up period was 6 months (range, 3-11 months). Conclusion: An asymmetric enlargement of the APD on L5 spinal root on CT scans is meaningfully associated with a foraminal or extraforaminal entrapment of the L5 spinal root on the lumbosacral junction.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.08a
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• pp.301-301
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• 2010

2010년경 2.5G APD 시장은 3, 000억원 규모로 증가하는데 이는 FTTH 망의 확산에 힘입은 바 크다. 이와 같이 중요한 APD 소자는 현재 광통신 부품시장을 석권해 가고 있는 대만, 중국 업체들은 제조기술을 갖고 있지 않고 주로 미국-일본 기술에 의존하고 있기 때문에 Niche market으로 중요한 부품이라 할 수 있다. APD의 증폭은 높은 전기장에 의해 얻어지는데, 이 때문에 메사형 구조로는 신뢰성을 확보하기 어렵게 되고 따라서 평면형(Planar) 구조로 설계-제작하게 된다. APD 소자는 증폭층의 너비에 의해 APD의 이득-대역폭이 정해지므로 증폭층 폭을 정확하게 조절하는 것은 매우 중요하다. 증폭층의 폭은 에피 성장과 같은 높은 정밀성을 갖는 장비에 의해 조절하는 것이 아니라, Planar 구조의 특성상 Zn-확산에 의해 조절하게 된다. 대부분의 경우 Zn-확산은 Zn 또는 $Zn_3P_2$를 증착하여 drive-in 시키는 방법을 사용하는데, 이 경우 Zn가 interstitial site를 치고 들어감으로 인해 캐리어 농도가 $2{\times}10^{17}\;cm^{-3}$ 정도로 낮게 형성된다. 따라서 높은 인가 바이어스에서 p-side로 공핍층이 전개되기 때문에 증폭층의 폭을 조절하기가 매우 어렵다. 이 현상은 APD 제작에 있어서 수율과 관련이 깊다. 따라서 APD의 증폭층 폭을 tight하게 조절하기 위해서는 p-type 캐리어 농도를 높일 수 있는 gas-phase 확산 방식의 개발이 필요하다. 이 방식에는 Ampoule과 같은 closed tube 방식과 확산로와 같이 Gas를 지속적으로 흘려주면서 확산시키는 open-tube 방식이 있다. Ampoule 방식은 캐리어 농도 측면에서는 가장 좋은 방식이나, Ampoule의 size 및 온도 균일성 등으로 인해 생산성에 문제가 있다. 따라서 open-tube 방식의 확산기술개발은 매우 중요하다 할 수 있다. 본 연구에는 rapid thermal annealing (RTA) 방법에 의한 $Zn_3P_2$ 고체의 확산 방식과 DEZn MO source에 의한 Gas 확산 방식을 바탕으로 InP로의 확산된 Zn원자와 doping의 분포를 비교하였다. 실험결과, Gas 확산방식의 경우 Zn원자가 더욱 더 깊게 확산이 되었으며, 확산된 원자의 대부분이 도펀트로 작용함을 확인할 수 있었다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.32 no.11A
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• pp.1213-1218
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• 2007

In this study, we have been constructed measuring system for spill over by the Japan TV broadcasting signals and analyzed those signals using APD curve. In Busan, we have been measured channel of Japan TV broadcasting signals during 9 months. The quality of image is that maximum grade is 2.5 level, and the quality of sound is that maximum grade is 3 level. In the result of analysis for measured Japan TV broadcasting signals, we have been observed Japan TV broadcasting signals those we have been chosen the ch 36 and ch 38, plotted the APD curve of each channel for a season, in Specially.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.54 no.11
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• pp.654-659
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• 2005

An improved power supply for APD(Avalanche Photo Diode) with a received optical power monitoring circuit allows the received optical power increase temporary without of the degradation of the electrical signal. For the cost reduction and simple fabrication, an improved power supply has been proposed that it was designed for driving a APD as a receiving device of a wireless optical transmission system. It was demonstrated that it was possible to improve a dynamic range by compensating the temperature coefficient of the APD up to 1.0 V/$^{\circ}C$ through the power supply. Also, for an efficient transmission at the receiver end, a simple structure of a single cylindrical micro-lens configuration was used in conjunction with the laser diode to partially compensate a laser beam ellipticity. For this purpose, an astigmatism introduced by the micro-lens is utilized for the additional compensation of the beam ellipticity at the receiver end. In this paper, it is demonstrated that an efficient beam shaping is realized by using the proposed configuration consisting of the single lens attached to the laser diode.