• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2008년도 하계학술대회 논문집 Vol.9
• /
• pp.504-505
• /
• 2008

We fabricated organic field-effect transistors (OFETs) based a fluorinated copper phthalocyanine ($F_{16}CuPc$) as an active layer. And we observed the surface morphology of the $F_{16}CuPc$ thin film. The $F_{16}CuPc$ thin film thickness was 40nm, and the channel length was $50{\mu}m$, channel width was 3mm. We observed the typical current-voltage (I-V) characteristics and capacitance-voltage (C-V) in $F_{16}CuPc$ FET and we calculated the effective mobility.

• 한국전기전자재료학회논문지
• /
• 제16권11호
• /
• pp.975-978
• /
• 2003

The microwave dielectric properties and the microstructures on B $i_{0.97}$T $m_{0.03}$Nb $O_4$ doped with $V_2$ $O_{5}$ were systematically investigated. B $i_{0.97}$T $m_{0.03}$Nb $O_4$ ceramics sintered at 920-96$0^{\circ}C$ were mainly consisted of orthorhombic and triclinic phases after addition of $V_2$ $O_{5}$. The apparent density increased slightly with increasing the $V_2$ $O_{5}$ addition. The dielectric constants($\varepsilon$$_{r}$) also increased with $V_2$ $O_{5}$ addition(30-45). The Q${\times}$ $f_{0}$ values measured on B $i_{0.97}$T $m_{0.03}$Nb $O_4$ ceramics doped with $V_2$ $O_{5}$ were between 2,000 and 12,000[GHz] when the sintering temperatures were in the range of 920-960[$^{\circ}C$]. It was confirmed that the temperature coefficient of the resonant frequency($\tau$$_{f}$) can be adjusted from a positive value of +10ppm/$^{\circ}C$ to a negative value of -15ppm/$^{\circ}C$ by increasing the amount of $V_2$ $O_{5}$ Based on our experimental results, the B $i_{0.97}$T $m_{0.03}$Nb $O_4$(added $V_2$ $O_{5}$) ceramics can be applied to multilayer microwave devices at low sintering temperatures.ng temperatures.emperatures.ratures.

• 대한화학회지
• /
• 제14권1호
• /
• pp.51-59
• /
• 1970

Methyl에서 n-butyl까지의 n-alkylamine 염산염동족체($RNH_3Cl$)의 "겉보기몰랄부피"(apparent molal volume)${\phi}_v$를 30$^{\circ}C$에서 여러가지 조성의 methanol-물 혼합액을 써서 측정하였다. 아민염의 농도는 0.01M까지, 밀도는 부력법을 적용하여 소수점이하 5위까지 택하였다. 관측된 ${\phi}_v$값을 무한대의 농도 쪽으로 extapolation하여 "분몰랄부피"(partial molal volume)$\bar{V}^{\circ}$V를 구하였다. 실험결과는 용질입자의 크기, charge 및 hydrophobic effect등에 관하여 논의되었고 또한 동족체간에일정한 몰랄부피차(${\Delta}\bar{V}^{\circ}$)를 갖는다는 사실과 아울러 혼합용매의 구조에 대하여도 검토하였다. 메탄올-물 0.1몰분율(m.f.)에서는 물의 구조증대로 cation의 "분몰랄부피($\bar{V}^{\circ}_+$)가 최소이고, 한편 0.4m.f. 에서는 charge 효과에 의한 electrostriction effect의 최대화 free volume이 최소라는 사실들이 관찰되었다.

• Journal of Ecology and Environment
• /
• 제42권4호
• /
• pp.174-182
• /
• 2018

Background: In this study, we observed their growth and physiological responses using a variety of duty ratio under the mixed light using red, blue, and white lights. The red+blue mixed light was treated with 95%, 90%, 85%, 80%, and 75% duty ratios and red+blue+white mixed light with 85% and 70% duty ratios. We examined the width and length of leaves, total number of leaves, and number of shoots to examine their growth responses. The physiological responses were studied by measuring their photosynthetic rate, transpiration rate, stomatal conductance, water use efficiency, chlorophyll content, and fluorescence ($F_o$, $F_m$, and $F_v/F_m$). Results: We found that lower duty ratio caused the length and width of the leaves to grow longer under red+blue mixed light but that it did not cause any difference in the red+blue+white mixed light condition. In addition, there was no difference in the number of leaves and shoots among all treatments. In the red+blue mixed light condition, the photosynthetic rate was no difference, but both transpiration rate and stomatal conductance were the highest at 95% duty ratio than in other ratios. Water use efficiency pattern was similar to that of photosynthetic rate; water use efficiency was no difference. Chlorophyll content was the highest at 95% duty ratios, and it was the least at 90%, 85%, and 75% duty ratio. $F_o$ and $F_m$ values were relatively high at 85% and 80% duty ratio and low at 90% duty ratio while $F_v/F_m$ showed no difference. Conclusions: Under the red+blue+white mixed light, all physiological items showed no difference between 70 and 85% treatments. But, photosynthetic rate, water use efficiency, chlorophyll content, and $F_v/F_m$ were relatively greater in the red+blue+white mixed light than in the red+blue mixed light. Therefore, red+blue+white mixed light treated with 70% duty ratio could lessen the environmental stress and save more power when cultivating Silene capitata in a plant factory.

• KSBB Journal
• /
• 제18권2호
• /
• pp.145-148
• /
• 2003

P. aeruginosa F722는 탄화수소를 분해하는 과정에 biosurfactant (BS)를 생산한다. 탄화수소 분해에 사용되는 C-배지에서 BS 생산량은 0.78 g/ $\ell$이었으나, 질소원과 탄소원을 각각 0.05% (w/v) NH$_4$Cl + 0.1% (w/v) yeast extract과 3.0% (w/v) glucose로 조정한 경우는 BS 생산량이 1.66 g/ $\ell$로 증가하였다. 최적의 BS 생산조건으로 배양하는 동안 air 1.0 LPM를 공급해 주었을 때는 공기를 공급하지 않을 때의 1.66 g/ $\ell$보다 약 20% 증가한 1.94 g/ $\ell$이었다 뿐만 아니라, glucose 분해속도는 대수증식기와 정지기에서 air를 공급하지 않은 경우 0.25, 0.18 h$^{-1}$ 였으나, 공기를 1.0 LPM으로 공급한 경우 0.33, 0.29 h$^{-l}$ 로 조사되었다.

• 대한수학회지
• /
• 제46권6호
• /
• pp.1309-1318
• /
• 2009

Let k be a positive integer, and let G be a simple graph with vertex set V (G). A Roman k-dominating function on G is a function f : V (G) $\rightarrow$ {0, 1, 2} such that every vertex u for which f(u) = 0 is adjacent to at least k vertices $\upsilon_1,\;\upsilon_2,\;{\ldots},\;\upsilon_k$ with $f(\upsilon_i)$ = 2 for i = 1, 2, $\ldot$, k. The weight of a Roman k-dominating function is the value f(V (G)) = $\sum_{u{\in}v(G)}$ f(u). The minimum weight of a Roman k-dominating function on a graph G is called the Roman k-domination number ${\gamma}_{kR}$(G) of G. Note that the Roman 1-domination number $\gamma_{1R}$(G) is the usual Roman domination number $\gamma_R$(G). In this paper, we investigate the properties of the Roman k-domination number. Some of our results extend these one given by Cockayne, Dreyer Jr., S. M. Hedetniemi, and S. T. Hedetniemi [2] in 2004 for the Roman domination number.

• 한국전자파학회논문지
• /
• 제30권4호
• /
• pp.282-285
• /
• 2019

본 연구에서는 2단계 게이트 리세스 방법을 사용하여 T-형 게이트 길이가 100 nm인 mHEMT 소자를 제작하였다. 제작한 소자는 65 mA의 드레인전류($I_{dss}$), 1090 mS/mm의 트랜스콘덕턴스($g_m$), -0.65 V의 문턱전압 ($V_{th}$) 등의 DC 특성을 보였다. 또한 차단주파수($f_T$) 190 GHz와 최대 공진주파수($f_{MAX}$) 260 GHz인 우수한 고주파 특성을 나타내었다. 제작한 mHEMT 소자는 향후에 W-대역의 MMIC 개발에 활용될 수 있을 것으로 기대된다.

• 대한정형도수물리치료학회지
• /
• 제11권2호
• /
• pp.62-70
• /
• 2005

The determination of peripheral nerve conduction velocity is an important part to electrodiagnosis. Its value as neurophysiologic investigative procedure has been known for many years but normal value of median and ulnar motor nerve was poorly reported in Korea. To evaluate of median and ulnar motor nerve terminal latency, amplitude of CMAP(compound muscle action potential), conduction velocity and F-wave latency for obtain clinically useful reference value. 71 normal volunteers(age, 19-65 years; 142 hands) examined who has no history of peripheral neuropathy, diabetic mellitus, chronic renal failure, endocrine disorders, anti-cancer medicine, anti-tubercle medicine, alcoholism, trauma, radiculopathy. Nicolet Viking II was use for detected terminal latency, amplitude of CMAP, conduction velocity and F-wave latency of median and ulnar motor nerve. Data analysis was performed using SPSS. Descriptive analysis was used for obtain mean and standard deviation, independent t-test was used to compare between Rt and Lt side also compare between different in genders. The results are summarized as follows: 1. Median motor nerve terminal latency was right 3.00ms, left 2.99ms and there was no significantly differences between right and left side and genders. 2. Median motor nerve amplitude of CMAP was right 17.26mV, left 1750mV and there was no significantly differences between right and left side and genders. 3. Median motor nerve conduction velocity was right 57.89m/sec, left 58.03m/sec and there was no significantly differences between right and left side and genders. 4. Median motor nerve F-wave latency was right 25.74ms, left 25.59ms and there was significantly differences between genders. 5. Ulnar motor nerve terminal latency was right 2.38ms, left 2.45ms and there was significantly differences between right and left side. 6. Ulnar motor nerve amplitude of CMAP was right 15.99mV, left 16.02mV and there was no significantly differences between right and left side and genders. 7. Ulnar motor nerve conduction velocity was right 60.35m/sec, left 59.73m/sec and there was no significantly differences between right and left side and genders. 8. Ulnar motor nerve F-wave latency was right 25.53ms, left 25.57ms and there was significantly differences between genders.

• Korean Chemical Engineering Research
• /
• 제54권2호
• /
• pp.157-162
• /
• 2016

다공성 $Co(OH)_2$ 나노플레이크 박막은 전위제어 전착법을 이용하여 티타늄 메쉬에 여러 전착전위(-0.75, -1.0, -1.2 및 -1.4 V)에서 전착하여 슈퍼커패시터에 이용하였다. 티타늄 메쉬에 전착된 $Co(OH)_2$ 나노플레이크 박막의 두께 및 전착량은 전착전위의 제어에 의해 결정되었고 -1.4 V에서 전착한 $Co(OH)_2$ 나노플레이크 박막의 두께는 약 $34{\mu}m$로 가장 두껍게 전착되었으며 전착량은 17.2 g이다. 전착전위 -0.75, -1.0, -1.2 및 -1.4 V에서 전착한 경우 초기 방전용량은 각각 226, 370, 720 그리고 $1,008mF\;cm^{-2}$으로 나타났고 1,000 사이클 후 각각 206, 349, 586 그리고 $866mF\;cm^{-2}$으로 나타났다. 또한 이들의 용량유지율은 각각 91, 94, 81 및 86%로 나타났다.

• 한국전기전자재료학회논문지
• /
• 제16권7호
• /
• pp.604-610
• /
• 2003

The effects of sintering additives such as B $i_2$ $O_3$ and $V_2$ $O_{5}$ on the microwave dielectric and sintering properties of (Z $n_1$$_{-xM}$ $g_{x}$)Ti $O_3$ system were investigated. Highly dense samples were obtained for (Z $n_{0.8}$M $g_{0.2}$)Ti $O_3$ at the sintering temperature range of 870~90$0^{\circ}C$ with B $i_2$ $O_3$ and $V_2$ $O_{5}$ additions of 〈1 wt.%, respectively. The microwave dielectric properties of (Z $n_{0.8}$M $g_{0.2}$)Ti $O_3$ with 0.45 wt.%B $i_2$ $O_3$ and 0.55 wt.% $V_2$ $O_{5}$ sintered at 90$0^{\circ}C$ were as follows : Q$\times$ $f_{o}$ = 50,800 GHz, $\varepsilon$$_{r}$ = 22, and $\tau$$_{f}$ = -53 ppm/$^{\circ}C$. In order to improve temperature coefficient of resonant frequency, Ti $O_2$ was added to the above system. The optimum amount of Ti $O_2$ was 15 moi.% when sintered at 87$0^{\circ}C$, at which we could obtain following results: Q$\times$ $f_{o}$ = 32,800 GHz, $\varepsilon$$_{r}$ = 26, and$\tau$$_{f}$ = 0 ppm/$^{\circ}C$.EX>.EX>.EX>.EX>.EX>.EX>.EX>.