• 전자통신동향분석
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• 제30권1호
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• pp.65-76
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• 2015

스마트폰의 보급에 따른 대용량 멀디미디어 서비스의 폭발적인 수요 증가에 따라데이터센터의 100Gb/s 광트랜시버에 대한 수요는 2017년을 기점으로 10Gb/s를 추월하여 2018년 데이터콤 전체 시장의 50% 이상을 차지할 전망이다. 한편, 데이터센터의 소비전력 및 시스템 집적도 증가를 위해 광트랜시버의 Form-factor는 CFP(40G/100G Form-factor Pluggable)에서 QSFP28($4{\times}28G$ Quad Small Form-factor Pluggable)로 약 1/14배 소형화될 전망이며, 이에 따른 광트랜시버 구성 부품의 집적도는 높아지고 소비전력은 현재 대비 1/9로 낮아져야 한다. 본고에서는 소형화 및 저전력화를 위한 광트랜시버의 표준화 및 기술동향과 국내외 시장동향에 대해 기술한다.

• 한국인터넷방송통신학회논문지
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• 제11권4호
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• pp.1-8
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• 2011

본 논문에서는 중심주파수 30 GHz에서 3 dB 대역폭(fractional bandwidth)이 50 % 이상인 마이크로스트립 대역통과필터(BPF)를 구현하였다. 구현된 BPF는 10 Gb/s 무선전송 THz 송수신기를 위한 IF 대역에서의 ASK(Amplitude Shift Keying) 방식 송수신용 필터로서 이용하고자 한다. 초광대역 특성을 갖는 마이크로스트립 BPF는 스텝 임피던스 저역통과필터(LPF)와 합성된 ${\lambda}_g/4$ 단락 스터브로 구성되며, LPF는 BPF의 상위 저지대역을 감쇠시키기 위해 사용되었고, ${\lambda}_g/4$ 단락 스터브는 하위 저지대역을 감쇠시키기 위해 사용되었다. 합성 BPF의 측정 결과, 중심주파수 30 GHz에서 삽입손실은 0.65 dB, 10 GHz와 50 GHz에서 저지 특성은 각각 -10 dB와 -16 dB이며, 20~40 GHz 통과대역에서 평탄도는 ${\pm}0.5$ dB로 측정되었다.

• 한국세라믹학회지
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• 제56권5호
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• pp.506-512
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• 2019

Although graphene has been successfully grown in large scale via chemical vapor deposition (CVD), it is still questionable whether the mechanical properties of CVD graphene are equivalent to those of exfoliated graphene. In addition, there has been an issue regarding how the tilt angle of the grain boundary (GB) affects the strength of graphene. We investigate the mechanical properties of CVD graphene with nanoindentation from atomic force microscopy and transmission electron microscopy. Surprisingly, the samples with GB angles of 10° and 26° yielded similar fracture stresses of ~ 80 and ~ 79 GPa, respectively. Even for samples with GB exhibiting a wider range, from 0° to 30°, only a slightly wider fracture stress range (~ 50 to ~ 90 GPa) was measured, regardless of tilt angle. The results are contrary to previous studies that have reported that GBs with a larger tilt angle yield stronger graphene film. Such a lack of angle dependence of GB can be attributed to irregular and well-stitched GB structures.

• 한국임상수의학회지
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• 제24권4호
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• pp.608-612
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• 2007

4년령의 중성화한 수컷 코커 스파니엘이 후지 마비와 진전 때문에 내원 하였다. 본 환축은 X-ray와 MRI를 이용하여 추간판탈출증이 합병된 척수연화증으로 진단되었다. 환축의 치료를 위하여 봉독 약침, 뜸 및 한약제의 투여를 이용하였다. 사용 혈위는 GV02-1, GV04, GV11, GV12, GV13, GV14, BL11, BL18, BL23, BL25, BL28, GB21, HT07, KI03, LI04, LU07, SI03, SI06, ST36, ST38, ST39, ST40, ST41, GB30, GB31, GB34, LIV03, SP06 및 압통점($T1{\sim}T4\;and\;T9{\sim}L1$) 이었다. 그 결과, 1차 치료 시 환축은 기립이 불가능하였으며, 사지를 움직이지 못하였다. 그러나 7차, 14차 및 21차 치료 시 점차적인 임상증상의 개선이 관찰되었다. 비록 한방수의학적 방법으로 임상 증상이 완치된 것은 아니지만, 21차 치료 후 임상증상이 일부 호전된 증례이었다.

• Korean Journal of Acupuncture
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• 제24권2호
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• pp.113-127
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• 2007

Objectives : To inform the 5th WHO Informal Consultation meeting on Development of International Standard Acupuncture Point Locations, held in Osaka, Japan, on September $27{\sim}29$, 2005. Results and Conclusions : Nine experts from Korea, China and Japan discussed the principles of acupuncture points locations and the point locations of 33 controversial acupoints that were not agreed at the previous meeting, as well as 328 non-controversial points that all 3 nations agreed on the locations to confirm the expression of every single point. Through this meeting, the locations of ST30, SP12, LR7 and expressions of LU6, LI8, LI9, LI10, LI 13, SP13, BL60, KI3, GB38, LR11, LR12 were agreed. Furthermore, locations of BL39, GB27, GB28 were confirmed out of 6 non-discussed points. However, several points were still required to held additional meeting to discuss. That includes LI19, LI20, ST36, ST37, ST38, ST39, SI6, KI9, PC8, PC9, TE9, TE17, TE23, GB7, GB30, GV26. In addition, foundation for the international society for the acupuncture point location was proposed to make a regular revision of standard acupuncture point location.

• Korean Journal of Acupuncture
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• 제26권3호
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• pp.27-42
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• 2009

Objectives : The vestibular system detects head movement and serve to regulate and maintain the equilibrium and orientation of the body. It is known that the vestibular imbalance leads to vestibular symptoms such as nausea, vomiting, vertigo and postural disturbance. The objectives of the present study were to examine a modification of the dynamic activities of medial vestibular nucleus (MVN) neurons following electroacupuncture (EA) of GB43 (Hyepgye). Methods : In Sprague-Dawley rats weighing $250{\sim}300g$, 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 (Hyepgye) with 0.2 ms, 40 Hz and $600{\pm}200{\mu}A$. Also, expression of cFos protein was observed 2 hours after EA for 30 mins. Results : In dynamic response of vestibular neuron, the excitatory or inhibitory responses of gain were predominant in the ipsilateral MVN neurons during EA but not predominant in the contralateral MVN. Most neurons showing decreased gain were classified to inhibitory responses of spontaneous firing discharge during EA and ones showing increased gain were classified to excitatory response of spontaneous firing discharge during EA. Also, EA of the left GB43 (Hyepgye) for 30 mins produced the expression of cFos protein in MVN, inferior olive (IO) and solitary tract nuclei (SOL). Spatial expressions of cFos protein were predominant in the contralateral MVN, ipsilateral IO and bilateral SOL. Conclusion : These results suggest that the excitability of MVN neurons was influenced by EA of GB43 (Hyepgye) and EA may be related to the convergence on MVN.

• 대한수의학회지
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• 제57권3호
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• pp.147-154
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• 2017

The present study was performed to evaluate the hangover relieving effect of germinated buckwheat (GB) and Sanghwang mushroom mycelium cultured in GB (SGB). Both GB and SGB showed 1,1-diphenyl-2-picrylhydrazyl radical scavenging activities and significantly increased (p < 0.001) aldehyde dehydrogenase (ALDH) activities; up to 140% increase at concentrations of $16{\mu}L/mL$. Locomotor activity test results from alcohol-SGB and alcohol-GB groups showed improved motor activities over that of the alcohol-water group at 90 min post-administration. Both alcohol-GB and alcohol-SGB groups had significantly reduced (p < 0.001) alcohol ($40.02{\pm}33.38{\mu}g/mL$, $66.01{\pm}22.04{\mu}g/mL$, respectively) and aldehyde ($5.72{\pm}0.47{\mu}g/mL$, $6.72{\pm}1.70{\mu}g/mL$, respectively) concentrations in blood compared to those in the alcohol-water group ($199.75{\pm}33.83{\mu}g/mL$, $50.43{\pm}13.88{\mu}g/mL$, respectively) at 90 min post-administration. Based on cDNA microarray analysis, expressions of ALDH genes ALDH1a7 and ALDH18a1 and cytochrome P450 (CY450) gene CYP4a30b were upregulated in the alcohol-GB and alcohol-SGB groups compared to levels in the control group. Overall, the results suggest that both GB and SGB have hangover relieving effects by reducing blood acetaldehyde levels. The molecular mechanisms may involve ALDH activation and upregulated expression of alcohol metabolism-related genes such as ALDH and CYP450.

• Journal of Acupuncture Research
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• 제30권3호
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• pp.125-134
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• 2013

Objectives : We studied the effects of electro and laser acupuncture treatment with $GB_{39}$ and $GB_{34}$ on neuropathic pain in rats induced by tibial and sural nerve ligation. Methods : To produce the model of neuropathic pain, the tibial and sural nerves of rats were ligated by a 6-0 silk thread. Three days after the neuropathic surgery, only electro acupuncture(EA), electro acupuncture and 830 nm laser acupuncture(EA-LA-1), and electro acupuncture and 904 nm laser acupuncture(EA-LA-2) were treated with $GB_{39}$ and $GB_{34}$ twice a week for 8 weeks. We observed the withdrawal response of neuropathic rats' legs by von Frey filament and acetone stimulation. We also observed c-fos and nocieptin on the central gray area in the midbrain of neuropathic rats. Results : As we observed the effect of mechanical allodynia, the EA and EA-LA-1 groups in 5 and 6 weeks and the EA-LA-2 group in 6 weeks increased significantly compared with the control group. As for the effect of c-fos activity in the central gray region, the EA, EA-LA-1, and EA-LA-2 groups decreased significantly compared with the control group. The EA-LA-2 group increased significantly compared with the control group as regards the effect of nociceptin activity in the central gray region. Conclusions : We noticed the synergic effect of electro and laser acupuncture treatment because the EA-LA-1 and EA-LA-2 groups had more controllable effect compared with the control group. This study can be used in clinical therapy for neuropathic pain.

• 대한방사선기술학회지:방사선기술과학
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• 제32권2호
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• pp.169-175
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• 2009

본 연구는 초음파진단장치의 3.5 MHz 프로브로 20대 정상 성인의 식전 후 쓸개용적과 쓸개벽두께를 시간별로 추적주사하고 이것들의 추이변화를 분석 평가하여 다음과 같은 결론을 얻었다. 1. 식전 평균 쓸개용적은 남자 47.40 $m\ell$(SD 9.05), 여자 35.72 $m\ell$(SD 8.30)이었다. 2. 식전 평균 쓸개벽두께는 남 여 모두 2.3 mm(SD 0.3, SD 0.5)이었다. 3. 평균 쓸개박출계수(%)는 남자 67.20%, 여자 63.95%이었다. 4. 쓸개용적은 남 여 모두 식후 4시간까지는 음상관관계(v = -.487, p < .000, v = -.509, p < .000), 4시간 이후는 순상관관계(v = .434, p < .000, v = .440, p < .000)를 보였다. 5. 쓸개벽두께는 남 여 모두 식후 3시간까지는 순상관관계(t = .310, p < .002, t = .116, p < .246), 3시간 이후는 음상관관계(t = -.288, p < .010, t = -.126, p < 7.10)를 보였다. 6. 남 여 쓸개용량과 벽두께의 시간별 추이는 역상관관계를 나타냈다.

• 대한소아치과학회지
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• 제34권4호
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• pp.579-589
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• 2007

본 연구에서는 최근에 개발된 치과용 접착제를 대상으로 유치와 영구치의 법랑질과 상아질에 대한 결합력을 비교 평가하여 임상에서 상아질 접착제를 적절하게 선택하는데 도움을 주고자 시행하였다. 실험재료로 Adper Scotchbond Multi-purpose Plus Adhesive (SM; 3M ESPE, USA), Adper Single bond 2 (SB; 3M ESPE, USA), Clearfil SE Bond (SE; Kuraray Medical Inc., Japan), Adper Prompt L-Pop (PL; 3M ESPE, USA), G-Bond (GB; GC Cooperation Toyko, Japan)를 이용하여 전단결합강도를 평가하여 다음과 같은 결과를 얻었다. 1. 유치 법랑질에서 전단결합강도는 SM이 $28.47{\pm}7.93\;MPa$로 가장 높았고 SB ($28.18{\pm}6.84$), PL ($24.02{\pm}6.14$), SE ($21.70{\pm}6.56$), GB ($17.70{\pm}6.68$) 순이었다. SM과 SB는 SE보다 통계적으로 유의하게 높은 결합강도를 보였으며, SM, SB, PL은 GB보다 높았다(p<0.05). 2. 유치 상아질에서 전단결합강도는 SE가 $28.72{\pm}14.44MPa$로 가장 높았고, PL ($20.10{\pm}6.13$), SM ($17.72{\pm}10.65$), SB ($15.48{\pm}2.66$), GB ($10.10{\pm}5.45$) 순이었으며 SE와 GB간에는 유의한 차이가 있었으나, 다른 군들 간에는 유의한 차이가 없었다. 3. 영구치 법랑질에서의 전단결합강도는 SB가 $28.36{\pm}5.68\;MPa$로 가장 높았고 SM ($22.77{\pm}4.63$), PL ($22.05{\pm}6.57$), SE ($21.74{\pm}4.62$), GB ($15.60{\pm}6.75$)순이었다. SB는 다른 접착제보다 통계적으로 유의하게 높은 결합력을 나타냈으며, GB는 가장 낮은 결합력을 보였다(p<0.05). 4. 영구치 상아질에서의 전단결합강도는 SM이 $28.22{\pm}5.56\;MPa$로 가장 높았고, SB ($21.68{\pm}7.44$), SE ($20.13{\pm}9.88$), GB ($14.30{\pm}6.81$), PL ($14.18{\pm}5.88$)순이었으며, SM은 PL, GB와 유의한 차이가 있었다(p<0.05). 5. 유치의 법랑질과 상아질 간에는 SM, SB, GB에서 유의한 차이가 있었고, 영구치 법랑질과 상아질 간에는 PL에서 유의한 차이가 있었다(p<0.05). 6. 유치 법랑질과 영구치 법랑질 간에는 모든 접착제에서 유의한 차이가 없었으나, 유치 상아질과 영구치 상아질 간에는 SM과 SB에서 유의한 차이가 있었다(p<0.05).