• 한국광학회:학술대회논문집
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• 한국광학회 2002년도 제13회 정기총회 및 2002년도 동계학술발표회
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• pp.54-55
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• 2002

• 한국광학회지
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• 제13권4호
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• pp.295-300
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• 2002

20 Gb/s 광 전송 시스템을 위한 광 송신기와 수신기를 전기적 시분할 다중 방식으로 제작하고 그 특성을 측정하였다. 특히 광 수신기의 핵심 회로인 클럭(19.906㎓) 추출 회로의 구현을 위해 반파장 지연 선로와 상용화된 EX-OR 소자를 이용한 NRZ-PRZ 변환기와 유전체 공진기를 이용한 협대역 대역통과 필터 및 마이크로스트립 대역통과 필터를 설계, 제작하였으며, 최종적으로 수신부에서 1:2로 역다중화된 10 Gb/s 신호의 비트 오율(BER)을 측정하였다. 제작된 송ㆍ수신기를 직접 연동하였을 때, 수신기의 수신 감도는 BER $1{\times}10^{-12}$에서 -26.2dBm을 나타내었다.

• 한국전자파학회논문지
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• 제17권2호
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• pp.171-177
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• 2006

클락 유지 기능을 가지는 저가의 고성능 40 Gb/s 클락 복원기를 위상 고정 루프를 적용하여 설계 및 제작하였다. 클락 복원기는 클락 추출기, RF 믹서, 주파수 판별기, 위상 변환기, 클락 유지 회로로 구성되어 있다. 추출된 40 GHz 클락은 10 GHz 유전체 공진 발진기와 위상이 동기된다. 위상 고정 루프를 사용한 클락 복원기는 기존의 유전체 공진 필터를 사용한 개방형 클락 복원기에 비해 클락의 안정성과 지터 특성이 크게 향상되었다. 측정된 지터의 실효치는 230 fs였다. 또한 입력 신호가 끊어질 경우, 유지 회로에 의해 연속적인 클락 유지가 가능하였다.

• 한국전기전자재료학회논문지
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• 제23권5호
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• pp.368-373
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• 2010

In this study, we have investigated the effects of Cr dopant on the bulk trap levels and grain boundary characteristics of $Bi_2O_3$-based ZnO (ZB) varistor using admittance spectroscopy and dielectric functions (such as $Z^*,\;Y^*,\;M^*,\;{\varepsilon}^*$, and $tan{\delta}$). Admittance spectra show more than two bulk traps of $Zn_i$ and $V_o$ probably in different ionization states in ZnO-$Bi_2O_3-Cr_2O_3$ (ZBCr) system. Three kinds of temperature-dependant activation energies ($E_{bt}'s$) were calculated as 0.11~0.14 eV of attractive coulombic center, 0.16~0.17 eV of $Zn_{\ddot{i}}$, and 0.33 eV of $V_o^{\cdot}$ as dominant bulk defects. The grain boundaries of ZBCr could be electrochemically divided into two types as a sensitive to ambient oxygen i.e. electrically active one and an oxygen-insensitive i.e. electrically inactive one. The grain boundaries were electrically single type under 460 K (equivalent circuit as parallel $R_{gb1}C_{gb1}$) but separated as double one ($R_{gb1}C_{gb1}-R_{gb2}C_{gb2}$) over 480 K. It is revealed that the dielectric functions are very useful tool to separate the overlapped bulk defect levels and to characterize the electrical properties of grain boundaries.

• 전자공학회논문지
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• 제50권12호
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• pp.71-79
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• 2013

본 논문에서는 이퀄라이저 적응기(adaptation)를 포함하는 12.5 Gb/s 저전력 수신단 설계에 대해서 기술한다. 샘플러와 직렬 변환기를 사용한 저전력 아날로그 이퀄라이저 적응기를 구현함으로써 채널과 칩 공정 변화에 능동적으로 적응할 수 있으며 그 적응 원리에 대해서 설명한다. 또한 저전력을 위한 전압 모드 송신기의 접지 기반 차동 신호를 수신하는 기술에 대해서 설명하였다. 17.6 dB의 피킹 이득을 갖는 CTLE(Continuous Time Linear Equalizer)는 6.25 GHz에서 -21 dB 손실을 갖는 채널의 길게 늘어지는 ISI(Inter Symbol Interference)를 제거한다. 45 nm CMOS 공정을 이용하여 eye diagram에서 200 mV의 전압 마진과 0.75 UI의 시간 마진을 갖고 0.87 mW/Gb/s의 낮은 전력 소모를 유지한다.

• 대한한방내과학회지
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• 제19권1호
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• pp.22-38
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• 1998

This study was to investigate the hepatoprotective and anticirrhotic effects of Ganyeumilhobang(GIE) on the acute and chronic liver injury induced by various agents. Chronic liver injury induced by dimethylnitrosamine(DMN) ; a new experimental model for cirrhosis and the intraperitoneal injection of dimethylnitrosamine in the rat. Acute liver njury induced by carbon tetrachloride$(CCl_4)$ and D-galactosamine ; a experimental model for acute liver injury, the administration of $CCl_4$ and the intraperitoneal injection of D-galactosamine in the rat. The development of fibrosis and acute liver injury by the three prescriptions were examined by the chemical analysis of AST, ALT, prothrombin time and hydroxyproline. The results obtained were as follows. 1. The increasing level of hydroxyproline volume induced by DMN in mice was decreased by the oral administration of GIB. 2. The degree of histological fibrosis and hepatic inflammatory cell infiltration induced by $CCl_4$ decreased by the oral administration of GIB. 3. The increase of senun AST and ALT of mice with acute liver damage induced by $CCl_4$ and D-galactosamine was inhibited by the administration of GIB. 4. The prolongation of prothrombin time(seconds) of mice acute liver damage induced by $CCl_4$ was shortened by the oral administration of GIB. 5. The liver of mice was hepatectomized partial1y after the oral administration of GIB. The mitotic index(% of nuclei), weight of liver, contents of protein, RNA and DNA synthesis of the liver tissue were increased by the oral administration of GIB.

• Journal of Acupuncture Research
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• 제33권3호
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• pp.1-16
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• 2016

Objectives : The objective of this study was to investigate the effects of Gentianae Macrophyllae Radix pharmacopuncture (GP) at Hwando (GB30) in neuropathic pain induced rats. Methods : Neuropathic pain in rats was induced by tibial and sural nerve transection. The rat subjects were divided into 6 groups : normal (Nor, n = 5), control (Con, n = 5), neuropathic pain- induced injected at GB30 with 1 mg/kg GP (GP-A, n = 5), 5 mg/kg GP (GP-B, n = 5) and 20 mg/kg GP (GP-C, n = 5), and neuropathic pain-induced injected with 1mg/kg Tramadol (Tramadol, n＝5). Injections were administered 2 times a week for a total of 5 treatments. After each treatment plantar withdrawal response was measured and after all 5 treatments were completed c-fos, Bax, Bcl-2, mGlu5 and leukocytes in the blood were analyzed. Results : 1. Groups GP-A, GP-B and GP-C showed a meaningful decrease in the withdrawal response of mechanical allodynia compared to the control group. 2. Groups GP-A, GP-B and GP-C showed a meaningful decrease in the expression of c-fos compared to the control group. 3. Groups GP-A and GP-C showed a meaningful increase in the expression of mGluR5 compared to the control group. 4. Groups GP-A, GP-B and GP-C showed a meaningful decrease in Bax/Bcl-2 ratio compared to the control group. Conclusion : These results suggest that Gentianae Macrophyllae Radix pharmacopuncture at Hwando (GB30) could decrease mechanical allodynia and could have analgesic and neuroprotective effects on the model of neuropathic pain.

• Nutrition Research and Practice
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• 제6권3호
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• pp.208-212
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• 2012

In the present study, we examined whether four grains including adlay (AD), buckwheat (BW), glutinous barley (GB), and white rice (WR) affect the duration of food residence in the gastrointestinal tract and hepatic enzyme activities in rats fed different combinations of the grains. The rats were raised for 4 weeks on a high fat diet based on the American Institute of Nutrition-93 (AIN-93G) diets containing 1% cholesterol and 20% dietary lipids. Forty male rats were divided into four groups and raised for 4 weeks with a diet containing one of the grains. Corresponding to the dietary fiber contents of the experimental grains, gut transit time was shortest in the rats fed GB and increased in the order of BW, AD, and WR. In addition, the accumulated shortest transit time occurred in the GB group. Gut transit time affected weight gain and major organ weight, as it was closely related to the absorption of nutrients. The level of thiobarbituric acid reactive substance (TBARS) in liver was higher in rats fed WR, AD, BW, and GB, indicating that the other grains decreased oxidative stress in vivo more than WR. Glutathione, glutathione peroxidase, and glutathione S-transferase levels in the AD, BW, and GB groups were significantly higher than those in the WR group. In conclusion, reduced colonic transit time has been implicated in reducing the incidence of colon cancer, as evidenced by populations consuming diets rich in fiber. Whole grains such as AD, BW, and GB may contribute to a significant supply of antioxidants to prevent oxidative stress if they are consumed in large amounts.

• 대한한의학회지
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• 제18권1호
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• pp.385-398
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• 1997

The location and local arrangement of motor, sensory neurons within brain stem, nodose ganglia, spinal ganglia and sympathetic ganglia projecting to rat's kidney and meridian point BL 23, GB 25 were investigated by HRP immunohistochemical methods following injection of 5% WGA-HRP into left kidney and meridian point BL 23, GB 25. Following injection of WGA-HRP into left kidney, anterogradely labelled sensory neurons were founded within either nodose ganglia and spinal ganglia. The sensory neurons innervating rat's left kidney were observed within spinal ganglia $T_{7}{\sim}L_3$. Sympathetic motor neurons innervating rat's left kidney were labelled within left suprarenal ganglia, either celiac ganglia, superior mesenteric ganglia, and sympathetic chain ganglia $T_{1}{\sim}L_3$. Sympathetic chain ganglia were concentrated in $T_{12}{\sim}L_1$. The sensory neurons innervating rat's meridian point BL 23 were founded within spinal ganglia $T_{2}{\sim}L_2$. They were numerous in spinal in ganglia $T_{10}{\sim}T_{12}$. Sympathetic motor neurons innervating rat's meridian point BL 23 were observed in suprarenal ganglia and greater splanchnic trunk, sympathetic chain ganglia from $T_1$ to $L_3$. They were concentrated in $T_{12}{\sim}L_3$. The sensory neurons innervating rat's meridian point GB 25 were labelled within spinal ganglia $T_{6}{\sim}T_{13}$. They were numerous in from T10 to $T_{12}$. Sympathetic motor neurons innervating rat's meridian point GB 25 were labelled within greater splanchnic trunk and sympathetic chain ganglia $T_{12}{\sim}L_3$. They were concentrated in $T_{13}{\sim}L_1$. This results neuroanatomically imply that the location of rat's motor and sensory neurons innervating meridian point BL 23 and GB 25 were closely related that of innervating kidney.

• Korean Journal of Acupuncture
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• 제25권3호
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• pp.117-135
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• 2008

Objectives: It is known that the vestibular imbalance leads to vestibular symptoms such as nausea, vomiting, vertigo and postural disturbance. Since the non-labyrinthine inputs from the limbs and viscera converge on the vestibular nucleus neurons receiving signal from peripheral vestibular endorgan, acupuncture to the periphery may influence the activities of vestibular nuclear neurons and produce a therapeutic effect on the vestibulacr symptoms. The present study was to examine a modification and characteristics of the static and dynamic activities of medial vestibular nucleus (MVN) neurons following electroacupuncture (EA) of GB43' acupoint. Methods: In 54 Sprague-Dawley adult male rats weighing 250${\sim}$300g, spontaneous firing discharges and dynamic responses induced by sinusoidal whole body rotation about vertical axis at 0.2 Hz were observed in MVN of rats during EA of GB43' acupoint, located between the left 4th and 5th toe, which is the territory of sural and peroneal nerves, with 0.2 ms, 40 Hz and 600${\pm}$200 ${\mu}A$. Results: EA of the left GB43' acupoint induced modifications of spontaneous firing rates in 45% of MVN neurons recorded, and the percentage of modified neurons was 44% in type I, 52% in type II and 46% in non-type neurons. The excitatory or inhibitory responses of spontaneous firing discharges were predominant in the ipsilateral MVN neurons during EA. The excitatory response was abolished after EA but the inhibitory response was prolonged after EA in the ipsilateral MVN. The neurons of MVN showing modified spontaneous firing discharges by EA showed lower frequency (${\geq}$10 spikes/sec) of mean spontaneous firing rates than non affected ones. Conclusion: These results suggest that the neuronal activities of MVN neurons were influenced by EA of GB43' acupoint and the effects of EA may be related to the convergence of the peripheral vestibular inputs and ascending somatosensory inputs on MVN.