• Title, Summary, Keyword: APD

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생체 임피던스

  • 서병설
    • Journal of Biomedical Engineering Research
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    • v.6 no.2
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    • pp.63-68
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    • 1985
  • Air pressure decay(APD) rate and ultrafiltration rate(UFR) tests were performed on new and saline rinsed dialyzers as well as those roused in patients several times. C-DAK 4000 (Cordis Dow) and CF IS-11 (Baxter Travenol) reused dialyzers obtained from the dialysis clinic were used in the present study. The new dialyzers exhibited a relatively flat APD, whereas saline rinsed and reused dialyzers showed considerable amount of decay. C-DAH dialyzers had a larger APD(11.70$\pm$1.32mmHg/min)compared to CF dialyzers(4.32$\pm$0.55mmHg/min)(p<0.05). However, there was no observable difference in the UFR between the two dialyzers. Neither APD nor UFR showed any significant increase with an increasing number of reuses for up to more than 20reuses. A substantial number of failures observed in APD(larger than 20mmHe/min)on the reused dialyzers(2 out of 40 CP and S out 26 C-DAK) were attributed to the Possible damage on the fibers. The CF 15-11 HFDs which failed APD test did not show changes in the UFR compared to normal dialyzers indicating that APD is a more sensitive test than UFR test to evaluate the integrity of the fibers.

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The effect of extracellular Mg2+ on action potential in guinea pig papillary muscles (기니픽 심장 유두근에서 magnesium이 활동전위에 미치는 영향)

  • Chang, Sung-Eun;Kim, Shang-Jin;Kang, Hyung-Sub;Kim, Jin-Shang
    • Korean Journal of Veterinary Research
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    • v.43 no.1
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    • pp.31-39
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    • 2003
  • We have investigated the effect of extracellular $Mg^{2+}$ ($[Mg^2+]_o$) on action potential duration (APD) in guinea pig papillary muscles by using microelectrodes. Increasing $[Mg^2+]_o$ resulted in progressive negative inotropic effect, progressive ascending depolarization of membrane potential, and increase in intracellular $Mg^{2+}$ concentration. In addition, increase in $[Mg^2+]_o$ from 1.1 to 3, 6, 10, and 20 mM produced a reversible dose-dependent shortening of both APD at 30% ($APD_{30}$) and 90% repolarization ($APD_{90}$), especially showing a tendency towards more remarkable prominent shortening in $APD_{30}$ than $APD_{90}$. Cooling from 37 to 33 and $27^{\circ}C$ diminished the $[Mg^2+]_o$-induced APD shortening. Increase in extracellular $Ca^{2+}$ concentration from 1.8 to 3.6 and 5.4 mM caused a significant depressed effect on the increasing $[Mg^2+]_o$-induced APD shortening. Furthermore, increase in $[Mg^2+]_o$ from 1.1 to 10 and 20 mM produced a significant depressed effect on the APD shortening induced by extracellular $Ca^{2+}$. Pretreatment of verapamil and imipramine significantly attenuated the increasing $[Mg^2+]_o$-induced APD shortening in both $APD_{30}$ and $APD_{90}$, whereas the $[Mg^2+]_o$-induced APD shortening was not affected by strophanthidin, glibenclamide and tetrabutylammonium. These findings suggest that the effects of $[Mg^2+]_o$ on APD are probably due to a decrease in ionic transport across plasma membrane. In conclusion, the present study indicates that $[Mg^2+]_o$ exerts antiarrhythmic activities by antagonistic actions on intracellular $Ca^{2+}$.

An Atopic Preventive Drink (APD) reduces Th2 cytokines in LPS-treated RAW 264.7 cells

  • Song, Gyl-Hoon;Park, Eui-Seong;Lee, Seung-Min;Kim, Tae-Young;Park, Kun-Young
    • CELLMED
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    • v.7 no.3
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    • pp.15.1-15.6
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    • 2017
  • We analyzed the effects of an Atopic Preventive Drink (APD) on the regulation of Th2 cytokines using RAW 264.7 macrophage cells. In the evaluation of nitric oxide (NO) production in cells, NO production levels were shown to be elevated only in the APD-treated group in a dose-dependent manner. In the lipopolysaccharide (LPS) with APD-treated group, NO production significantly decreased as APD concentration increased. Further, mRNA expression levels and protein concentrations of pro-inflammatory cytokines in cells were determined. Th2 stimulatory cytokine ($IL-1{\beta}$) and Th2 cytokine (IL-6 and IL-10) levels were significantly reduced in the LPS with APD-treated group compared to the only LPS-treated group. mRNA expression levels of inflammatory-related genes (COX-2 and iNOS) were significantly reduced in the LPS with APD-treated group compared to the only LPS-treated group. These results suggest that APD has an anti-atopic effect by reducing mRNA and proteins expressions of Th2 cytokines and inflammatory-related genes.

Lithospermic acid modulate the Action potential duration by increasing Ica current in the rat ventricular myocyte

  • An, Seong-Hun;Kang, Dae-Gill;Lee, Ho-Sup;Lee, Suk-Ho;Earm, Yung-E
    • Proceedings of the Korean Biophysical Society Conference
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    • pp.55-55
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    • 2001
  • We observed the APD of rat ventricle myocyte and the effects of Lithospermic acid that was separated at Salvia miltiorrhiza having used in Oriental medicine by using classical whole cell patch clamp technique. We classified APD into APD30mV, APD0mV, APD-50mV, APD-60mV by cell membrane potential and the mean of cell resting membrane potential was -69.44${\pm}$1.72 mV.(omitted)

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Frquency Characteristics of Electronic Mixing Optical Detection using APD for Radio over Fiber Network (무선 광파이버 네트웍(RoF)을 위한 APD 광전 믹싱검파의 주파수 특성)

  • Choi, Young-Kyu
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.58 no.7
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    • pp.1386-1392
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    • 2009
  • An analysis is presented for super-high-speed optical demodulation by an avalanche photodiode(APD) with electric mixing. A normalized gain is defined to evaluate the performance of the optical mixing detection. Unlike previous work, we include the effect of the nonlinear variation of the APD capacitance with bias voltage as well as the effect of parasitic and amplifier input capacitance. As a results, the normalized gain is dependent on the signal frequency and the frequency difference between the signal and the local oscillator frequency. However, the current through the equivalent resistance of the APD is almost independent of signal frequency. The mixing output is mainly attributed to the nonlinearity of the multiplication factor. We show also that there is an optimal local oscillator voltage at which the normalized gain is maximized for a given avalanche photodiode.

A Study on Performance Reduction Characteristics of Digital Wireless Communication by APD (APD 통계 모델에 의한 디지털 무선 통신 성능 저감 특성 연구)

  • Lim, Sung-Jin;Hur, Min-Ho;Kwon, Se-Woong;Yoon, Young-Joon
    • Proceedings of the Korea Electromagnetic Engineering Society Conference
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    • pp.8-12
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    • 2003
  • To protect digital communications and broadcasting that are expected to be increasingly used at frequencies above 1GHz, there is a need to determine permissible disturbance limits for frequency bands above 1GHz according to indicates that better correlates with interference level in digital systems. The quality of digital communications is expressed in terms of bit error rate(BER) or throughput. In this regard, it has been reported that degradation of BER or throughput can be estimated from the amplitude probability distribution (APD) of disturbance amplitude. Therefore, if the APD can simply be measured with a high accuracy, APD will be an optimal index for the assessment of interference in digital communications. In this paper, we show that a measurement method using statistic model of APD has compatibility about performance reduction estimation of WLAN. And through approach of this inspection, we propose numeral models about interference effects of peak value and time rate of spurious.

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Fabrication of InP/InGaAs Avlanche Photodeode with Floating Guard Ring by Double Diffusion (Floating Guard Ring 구조를 갖는 InP/InGaAs Avalanche Photodiode의 이중확산 방법에 의한 제작)

  • 박찬용;강승구;현경숙;김정수;김홍만
    • Korean Journal of Optics and Photonics
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    • v.7 no.1
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    • pp.66-71
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    • 1996
  • We analyzed and fabricated InP/InGaAs avalanche photodiode (APD) having floating guard ring (FGR). Since the FGR-APD is very simple to fabricate and highly reliable, the fabrication of FGR-APD and its application to the optical receiver are very useful and interesting. A double zinc diffusion was employed to fabricate and one dimensional electric field analysis was used for design. Two dimensional gain measurement showed that the FGR suppressed gain at the curved edge, indicating the successful behavior as a guard ring. The fabricated device had 35 GHz of gain-bandwidth product, and showed the sensitivity of -31.9 dBm at a bit error rate of $10^{-9}$ when it was applied to a 2.5 Gbps optical receiver.

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Power supply for the enhancement of dynamic range of APD (APD의 다이나믹 레인지 향상을 위한 전력 공급기)

  • ;;Boris Fursa
    • Proceedings of the Optical Society of Korea Conference
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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)

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Advanced Paper Documents in a Projection Display (프로젝션 화면 내에서의 Advanced Paper Document)

  • 홍광진;정기철
    • Proceedings of the Korean Information Science Society Conference
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    • pp.565-567
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    • 2004
  • 최근 컴퓨터 환경은 매우 빠르게 발전하고 있지만, 사람들은 여전히 종이로 된 문서를 사용한다. 본 논문은 프로젝션 화면 내에서 종이 문서의 기능을 향상시킨 Advanced Paper Document (APD)를 제안한다. APD는 종이 문서와 디지털 문서를 결합시키기 위해서 부가적인 장치 없이, 사용자의 손을 이용한 문서의 선택과 조작 등의 다양한 명령을 수행한다. APD는 종이 문서와 디지털 문서의 장점을 모두 가지고 있으며, 사용자에게 자연스럽고 직관적인 환경을 제공한다. 실험 결과를 통해서, APD가 종이 문서와 디지털 문서의 기능을 결합하는 데에 적합하며, 손의 추출 및 인식과 문서의 검색에서 만족스러운 성능을 보여줌을 확인하였다.

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A 2.4 GHz 802.11b Throughput Estimation In a Noisy Environment Using an Experimental Noise Parameter

  • Hur Min-Ho;Lim Sung-Jin;Kwon Sewoong;Yoon Young-Joong
    • Journal of electromagnetic engineering and science
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    • v.5 no.2
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    • pp.61-65
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    • 2005
  • In this paper, a numerical permissible disturbance model is proposed to preserve a throughput performance of a 2.4 GHz wireless LAN service. The model is composed of two parameters, a peak value and a time rate of noise signal. The model parameters are experimentally determined from an APD parameter measurement. The APD parameter is measured by using the APD measurement method which is recommended from CISPR/A/447/CD.