• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제54권7호
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• pp.339-342
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• 2005

We present a new high-frequency equivalent circuit model for 52pin QFP used in typical IC's and extract R, L, and C values of this circuit model using a 3-D E & M field simulator. Futhermore, L and C value variations as a function of Pin number due to the shape differences of the leads have been fitted to 2nd order polynomials in order to extend the applicability of this model.

• 대한수학회보
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• 제47권2호
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• pp.319-339
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• 2010

In this paper, we prove that if $f^nf'\;-\;P$ and $g^ng'\;-\;P$ share 0 CM, where f and g are two distinct transcendental meromorphic functions, $n\;{\geq}\;11$ is a positive integer, and P is a nonzero polynomial such that its degree ${\gamma}p\;{\leq}\;11$, then either $f\;=\;c_1e^{cQ}$ and $g\;=\;c_2e^{-cQ}$, where $c_1$, $c_2$ and c are three nonzero complex numbers satisfying $(c_1c_2)^{n+1}c^2\;=\;-1$, Q is a polynomial such that $Q\;=\;\int_o^z\;P(\eta)d{\eta}$, or f = tg for a complex number t such that $t^{n+1}\;=\;1$. The results in this paper improve those given by M. L. Fang and H. L. Qiu, C. C. Yang and X. H. Hua, and other authors.

• 대한화장품학회지
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• 제43권4호
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• pp.337-347
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• 2017

본 연구에서는 참마와 명아주의 항산화 및 항염증 효능을 평가하기 위해 참마와 명아주 에탄올 추출물을 이용하여 free radical 소거활성, enzyme-linked immunosorbent assay (ELISA) 실험을 수행하였다. 참마와 명아주 추출물의 free radical (1,1-diphenyl-2-picrylhydrazyl, DPPH) 소거활성($EC_{50}$)에서 각각 2.386, 0.524 mg/mL로 측정되었다. 또한 참마와 명아주 추출물의 혼합 시료의 free radical 소거활성은 참마 추출물:명아주 추출물 비율이 2:1일 때 가장 뛰어난 것으로 나타났다. IL-6와 $TNF-{\alpha}$의 ELISA 실험을 통해 항염증효능을 평가한 결과, 마우스 비장세포에서 IL-6의 경우 1 mg/mL 농도에서 참마 추출물은 대조군과 대비하여 27.17% IL-6 생성을 감소시켰으며, 명아주 추출물은 72.30%의 감소를 나타내었다. $TNF-{\alpha}$의 경우 참마 추출물은 61.97%, 명아주 추출물은 77.85%로 유의성 있는 $TNF-{\alpha}$생성 감소 효능을 나타내었다. 이 결과들을 통하여 참마와 명아주 추출물은 항산화, 항염증 효능을 가지고 있으며, 이를 활용하여 항염증에 효과가 있는 천연물 제제에 응용 가능성이 있음을 확인하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 하계학술대회 논문집 C
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• pp.1933-1935
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• 2004

본 연구에서는 변압기형 플라즈마 전류 모델을 기초로 한 평판형 유도 결합 플라즈마 장치에 대한 회로를 분석하여 임피던스 매칭 특성을 조사하였다. 장치 임피던스는 collisional surface impedance를 기반으로 계산된 플라즈마 임피던스와 안테나 임피던스로 결정된다. 매칭 network에 사용된 회로는 Altcmatc-typc의 회로이고, 매칭 소자인 $C_T$와 $C_L$은 임피던스 매칭 조건을 이용하여 계산하였다. 완전 매칭의 경우에는 $C_T$와 $C_L$을 플라즈마 변수들의 함수로 표현하여 의존성을 분석하고, 불완전 매칭의 경우에는 반사파에 대한 반사계수, 반사율을 계산하였다.

• 한국축산시설환경학회지
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• 제8권3호
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• pp.153-158
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• 2002

활성오니처리를 한 양돈폐수 방류수의 잔여오염물질을 정화하고 색도 구성물질을 분해하고자 4개의 오존처리조와 폭기조, 침전조 등으로 구성된 처리소 총 처리조용량이 594.5l이고 1일 200l씩 처리가 가능한 20g/hr의 오존발생기가 부착된 오존이용 탈색 시스템을 개발하였으며 그 시험 결과는 다음과 같다. 1. 오존처리시 온도는 반응열에 의하여 처리전 31.$0^{\circ}C$에서 처리중에는 41.9$^{\circ}C$까지 증가하였으며 pH도 처리 과정 중에 계속적으로 증가했다. 2. 산화환원전위차는 처리전에 148㎷였으나 처리중에 증가하여 330㎷까지 증가하였으며 처리가 완료된 후 방류조에서는 다시 감소하였다. 3. BOD의 경우 처리전 11mg/l였으나 처리후에 1mg/l로 낮아졌으며 CO $D_{MN}$ 의 경우에도 83mg/l에서 1.0mg/l으로 낮아졌다. 4. 활성오니처리 방류수의 색도는 442도였으나 오존처리후에는 색도가 6도로 98.6%의 높은 색도제거효율을 보였다.

• Journal of Nutrition and Health
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• 제33권3호
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• pp.296-303
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• 2000

We examined the folate intakes and assessed folate nutritional status of Korean women with childbearing potential. A total of 91 healthy women aged between 15 and 49 participated. They were divided into three groups by their age : A(15-24 yrs), B(25-34 yrs) and C(35-49 yrs). Folate intakes were determined by direct analysis. The foods consumed for 24 hours were collected proportionally and assessed folate. Their blood drawn in fasting state were analyzed folate levels. Folate contents of food homogenate, plasma and erythrocyte were determined a microbiological method using Lactobacillus. casei (ATCC 7469). Prior to the micro-assay, the food homogenate were treated with alpha-amylase, protease and folate conjugase. Mean daily folate intake of the total subjects was 145.8$\mu\textrm{g}$/d and in each group of A, B, and C was 114.0$\mu\textrm{g}$/d, 141.6$\mu\textrm{g}$/d, and 164.6$\mu\textrm{g}$/d, respectively. That of group C was significantly higher than that of group A(p<0.05). However, those of all the groups were lower than compared to the Korean Recommened Dietary Allowances(RDA) for folate. Especially the subjects in the group A consumed folate least that was below the half of the Korean RDA. The mean energy intake of all subjects was 1638㎉/d and those in each group of A, B, and C did not meet the Korean RDA for energy. The energy intake were significantly correlated with folate intakes(r=0.5050, p<0.001). Mean plasma and erythrocyte folate concentrations of total subjects were 6.9ng/mL and 266.3ng/mL, respectively. None were found to be deficient both in plasma(<3ng/mL)and erythrocyte (<140ng/mL) folate levels. There was only one subject who had red blood cell folate level below 157ng/mL concentration. These results show that folate status of the Korean women of reproductive age is not much bad. But it should be better that letting them improve their folate status by increasing energy intake, choosing high folate foods.

• 한국물환경학회지
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• 제30권3호
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• pp.261-268
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• 2014

Four clays (both natural and commercial types) mainly used in Korea were tested for removal efficiency of Microcystis spp. and ecotoxicity on Daphnia magna and Vibrio fischeri. Four clays (clay A~D) were composed of 91.9~100% of sand (0.02~0.2 mm in particle size). Clay D consisted of lager particles than other clays. Major elements of the four clays were $SiO_2$ (45.3~62.8%), $Al_2O_3$ (18.5~29.7%) and $Fe_2O_3$ (5.4~7.9%). They contained kaolinite (clay mineral), quartz, muscovite, and so on. Clay C and D contained montmorillonite, one of the clay minerals improving clay-cell aggregation. For clay A, B and C, removal efficiency of Microcystis spp. was over 60% at 2 g/L. It reached about 100% at over 5 g/L. For clay D, it was over 60% and 95~100% at 5 g/L and 20 g/L respectively. After adding clays, pH decreased. The greatest drop of pH appeared at clay C. Except for addition of 100 g/L clay C, ecotoxicity on D. magna and V. fischeri didn't appeared at all dose of clays.

• 대한수학회보
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• 제56권4호
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• pp.815-827
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• 2019

It is well known that the denominator of the Dedekind sum s(c, d) divides 2 gcd(d, 3)d and that no smaller denominator independent of c can be expected. In contrast, here we prove that we usually get a smaller denominator in S(H, d), the sum of the s(c, d)'s over all the c's in a subgroup H of order n > 1 in the multiplicative group $(\mathbb{Z}/d\mathbb{Z})^*$. First, we prove that for p > 3 a prime, the sum 2S(H, p) is a rational integer of the same parity as (p-1)/2. We give an application of this result to upper bounds on relative class numbers of imaginary abelian number fields of prime conductor. Finally, we give a general result on the denominator of S(H, d) for non necessarily prime d's. We show that its denominator is a divisor of some explicit divisor of 2d gcd(d, 3).

• 한국응용과학기술학회지
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• 제32권3호
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• pp.451-460
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• 2015

An enantioselective recognition of D- and L-tryptophan (Trp)-b-cyclodextrin (CD) inclusion complex was performed using electrochemical and FT-Raman spectroscopic analysis. From the electrochemical analysis, the selectivity coefficient ($K_{DL}$) of b-CD inclusion complexes was found higher than that of the D- and L-Trp in phosphate buffered saline (PBS, pH=7.0) solution. The percentage of enantioselectivity ($I_{%{ee}}$) for peak current of D-Trp-b-CD inclusion complexes was observed higher than that of L-Trp-b-CD inclusion complexes in PBS solution. From Raman spectroscopy, chemical shift difference (D, $cm^{-1}$) for the C=C stretch, ring vibration, and ring breathing of D-Try-b-CD inclusion complex were observed higher than that of L-Trp-b-CD inclusion complex. The electrochemical and Raman spectroscopic analyses were found very useful for chiral detection of racemic amino acid in the presence of b-CD.

• 한국마이크로전자및패키징학회:학술대회논문집
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• 한국마이크로전자및패키징학회 2002년도 추계기술심포지움논문집
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• pp.73-77
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• 2002

n형 SiC를 이용한 오옴성 접합을 알아보고자 Cu/Si/Cu 형태의 접합실험을 실시하였다. 오옴성 접합의 형성을 위하여 Cu/Si/Cu를 증착 하고 열처리를 시행하였다. 열처리는 RTP를 이용한 진공상태의 2-step 방법으로 시행하였다. 접합에 계산을 위하여 TLM구조로, 면 저항(Rs), 접촉저항(Rc), 이동거리(L$_{T}$), 패드간거리(d), 저항(R$_{T}$)값을 구하면 접합비 저항(Pc) 값을 알 수 있다. 이로 인한 결과 값은 접촉저항 값은 2$\Omega$이었고, 이동간 거리는 1$\mu\textrm{m}$이었으며 접합비저항($\rho$c)=1.0x$10^{-6}$ $\Omega$$\textrm{cm}^2$ 값을 얻을 수 있었다. 물리적 변화를 AES 및 XRD를 이용하여 알아보았다. SiC 계면 상에 Cu의 변화로 인한 silicide형성이 이루어짐을 알 수 있었다.있었다.