• 대한기계학회논문집
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• 제14권1호
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• pp.207-213
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• 1990

본 연구에서는 종횡비(aspect ratio` A=H/L)가 1 이하인 직각밀폐용기내 수평 경계면이 자연대류열전달에 미치는 영향을 조사하기 위해 단열조건인 경우와 등온조건 인 경우 { $T_{H}$.simeq. $T_{T}$＞ $T_{C}$.simeq. $T_{B}$, 따라서 온도차의 비, .DELTA. $T_{V/}$ .DELTA. $T_{H}$=( $T_{T}$- $T_{B}$)/( $T_{H}$- $T_{C}$).simeq.1} Mach-Zehnder간섭계 및 수치해석 을 통해 온도장 및 각 면에서의 열전달특성의 차이를 자세히 구명하였다. 특히 등온 수평면조건인 경우 상부수평면온도가 하부수평면온도보다 높을 때 ( $T_{T}$＞ $T_{B}$) 직각용기내는 수직방향으로 안정된 온도구배가 형성되어, 양단온도차(.DELTA. $T_{H}$= $T_{H}$- $T_{C}$)에 의해 기본적으로 존재하는 자연대류흐름을 억제하게 된다. 이때 자연대류흐름의 억제정도를 나타내는 주요 물리적 변수로서 온도차의 비, .DELTA. $T_{V/}$ .DELTA. $T_{H}$가 있다. 이러한 물리적 현상은, 기본적으로 존재하는 유체내 자연대류효 과를 억제함으로써 중력장하에서 양질의 결정을 얻고자 하는 결정성장(growth of cry- stal)등에 관계된다. 본 연구는 실험유체가 공기이고 .DELTA. $T_{V/}$.DELTA. $T_{H}$=1인 경우 를 택하여 일반적인 단열조건의 경우와 열전달특성의 차이를 비교한 것이다.전달특성의 차이를 비교한 것이다.다.전달특성의 차이를 비교한 것이다.

• 한국정보전자통신기술학회논문지
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• 제11권3호
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• pp.283-289
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• 2018

샘플-홀드 커패시터와 전압제어발진기 신호에 동작하는 피드포워드 루프필터를 가진 단방향 전하펌프를 가진 위상고정루프를 제안하였다. 제안된 위상고정루프는 기존의 2차 RC 필터에 비해서 저항 대신에 스위치와 작은 작은 크기의 커패시터를 사용하여 칩 크기를 줄일 수 있을 뿐만 아니라 전압제어발진기의 위상잡음에 영향을 미치는 ${\Delta}VLPF$의 변화량과, 기준신호 의사잡음에 영향을 미치는 ${\Delta}{\Delta}VLPF$의 변화량을 각각 1/5과 1/6로 줄였다. 제안된 위상고정루프는 1.8V $0.18{\mu}m$ CMOS 공정을 이용하여 시뮬레이션을 통해 위상잡음 특성이 개선된 동작을 확인하였다. 향후 시뮬레이션을 바탕으로 칩을 제작하여 성능을 검정할 계획이다.

• 한국응용과학기술학회지
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• 제15권4호
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• pp.35-44
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• 1998

All the triacylglycerols including the molecular species having ${\Delta}^5$-unsaturated fatty acids from the seeds of Pinus Koraiensis, were split into a mixture of diacylglycerols by a Grignard reagent prepared with allyl bromide without arousing acyl chains of a glycerol moiety to migration, and were also easily partially hydrolyzed to diacylglycerols by pancreatic lipase. (S)-(+)-(1-naphthyl)ethyl urethane(NEU) derivatives of the diacylglycerol mixture derived from the triacylglycerols were fractionated into sn-1, 3-, sn-1, 2- and sn-2, 3-DG-NEU by silica-HPLC and the fatty acid composition of these fractions was analysed. $C_{18:1{\omega}9}$ is distributed evenly in the three positions of TG with $C_{18:2{\omega}6}$ mainly located in sn-2 position, while ${\Delta}^5$-unsaturated fatty acids such as ${\Delta}^{5.9}-C_{18:2}$, ${\Delta}^{5.9.12}-C_{18:3}$ and ${\Delta}^{5.11.14}-C_{20:3}$ are exclusively present in the sn-3 position. These results could be confirmed by $^{13}C$-NMR spectroscopy : the signals at $^{\delta}$173.231 ppm and $^{\delta}$172.811 ppm of the carbonyl carbon of acyl moieties indicate the presence of saturated acids and/or $C_{18:1{\omega}9}$ (oleic acid) in the ${\alpha}({\alpha}')$- or ${\beta}$- positions, and $C_{18:2{\omega}6}$ including $C_{18:1{\omega}9}$ in the ${\beta}$-position, respectively. In addition, the resonance at $^{\delta}$173.044 ppm suggested a location of ${\Delta}^5$-unsaturated fatty acid moiety in the ${\alpha}({\alpha}')$-position.

• 농촌의학ㆍ지역보건
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• 제2권1호
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• pp.36-42
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• 1977

A study on blood pressure and hematocrit values of 1,559 people in 19 Korean rural areas was carried out in 1974 and the results were analyzed statistically. Obtained as follows: 1. The blood pressure according to sex and age groups (from the twenties to the seventies) was as follows: 1) The blood pressure of male by age group il) In the twenties, M (mean) was 125. 85/74, 15mm/Hg, a (standard deviation) was 15.9/10.2, and ill (standard error) was 1.55/0.99. (2) In the thirties, ${\delta}$ was 123.93/77.19 mm/Hg, a was 14.4/10.8, and m was 1.24/0.93. (3) In the forties, M was 128.44/81.15 mm/Hg, a was 23.9/14.7, and m was 2.16/1.33. (4) In the fifties, M was 128.48/181.24 mm/Hg, a was 24.7/13.9, and m was 2.05/1.16. (5) In the sixties, M was 135.80/81.70 mm/Hg, a was 27.4/18.8, and ${\delta}$ was 2.74/1.88. (6) In the seventies, M was 146.84/83. 16mm/Hg, ${\delta}$ was 24.5/10.0, and m was 5.62/2.30. 2) The blood pressure of female by age group (1) In the twenties, M was 117.89/73.33 mm/Hg, ${\delta}$ was 15.7/12.1, and m was 1.42/1.09. (2) In the thirties, M was 118.04/75.71 mm/Hg, ${\delta}$ was 16.9/13.0, and m was 1.13/0.87. (3) In the forties, M was 120.92/78.17 mm/Hg, ${\delta}$ was 20.9/12.9, and m was 1.42/0.87. (4) In the fifties, M was 122.14/79.55 mm/Hg, ${\delta}$ was 24.2/15.9, and m was 1.63/1.07. (5) In the sixties, M was 131.57/84.29 mm/Hg, ${\delta}$ was 28.4/16.9, and m was 2.58/1.53. (6) In the seven ties, M was 139.62/86, 54 mm/Hg, ${\delta}$ was 22.4/15.7, and m was 4.38/3.09. And the range of systolic blood pressure in male was 70~230 mm/Hg and in female was 80-230 mm/Hg. The range of distolic blood pressure in male was 50~160 mm/Hg and in female was 40~140 mm/Hg. 2. The hematocrit value according to sex and age groups was as follows: 1) The hematocrit values of male by age group (1) In the twenties, M was 42.72%, ${\delta}$ was 3.05, and m was 0.30. (2) In the thirties, M was 41.77%, ${\delta}$ was 3.29, and m was 0.28. (3) In the forties, M was 41.39, ${\delta}$ was 3.86, and m was 0.35. (4) In the fifties, M was 40.12%, ${\delta}$ was 3.65, and m was 0.30. (5) In the sixties, M was 39.88%, ${\delta}$ was 3.81. and m was 0.38. (6) In the seventies, M was 38.47%, ${\delta}$ was 2.27, and m was 0.52. 2) The hematocrit values of female by age group (1) In the twenties, M was 35.40%, ${\delta}$ was 3.37, and m was 0.30. (2) In the thirties, M was 35.50%, ${\delta}$ was 3. 35, and m was 0.22. (3) In the forties, M was 35.75%, ${\delta}$ was 3. 18, and m was 0.22. (4) In the fifties, M was 35.84%, ${\delta}$ was 3.30, and m was 0.22. (5) In the sixties, M was 35.70%, ${\delta}$ was 3.35, and m was 0.30. (6) In the seventies, M was 35.08%, ${\delta}$ was 3.08, and m was 0.60. The range of hematocrit values in male was 23~50% and in female was 18~50% (un associated with age groups). 3. In comparison with the blood pressure and the value of hematocrit of study groups showed that the blood pressure raised higher but the value of hematocrit got lowered on the contrary as the groups are getting older. 4. Total number of patients with hypertension was 165(10.6%) which were consisted with 71 male (11.3%) and 94 female (10.1%). But only two cases of the male patient and one case of the female patient were associated with protein uria. 5. The incidence of anemia by hematocrit values was as follows: 1) The incidence of male anemia patients based on$\leqq$41% ($\leqq$39%). (1) In the twenties, incidence was 43.90% (16.98%). (2) In the thirties, 41.48% (25.93%). (3) In the forties, 42.62% (25.41%). (4) In the fifties, 62.76% (40.69%). (5) In the sixties, 70% (38%). (6) In the seventies, 84.21% (73.68%). 2) The incidence of female anemia patients bailed on $\leqq$35% ($\leqq$34%). (1) In the twenties, incidence was 43.90% (37.39%). (2) In the thirties, 48.21 % (33.93%). (3) In the forties, 43.58% (32.57%). (4) In the fifties, 45.91 % (34.09%). (5) In the sixties, 47.11% (37.19%). (6) In the seventies, 50% (46.15%) 6. The incidence rate of anemia patients with hypertension was highest in the age group 51~60 in male and 31~40 in female.

• 한국미생물·생명공학회지
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• 제25권6호
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• pp.571-579
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• 1997

For the overproduction of pectate lyase (PL), the recombinant plasmid pl2BS fl which has strong promoter from alkali-tolerent Bacillus sp. YA-14 was used. In order to overexpress the pectate lyase by the action of overlapping strong promoter in pl2BS$\Delta$fl, 1.6 kb of PL gene was inserted into pl2BS$\Delta$fl to form pl2BS$\delta$f1-PL and the enzyme was expressed. But decreased expression efficiency of the PL gene was observed and it was due to the presence of the transcription terminator region on the upstream of the PL gene. The transcription terminator of the PL gene in pl2BS$\delta$f1-PL was removed and the resulting plasmid p12BS$\Delta$fl$\Delta$PL was formed. Bacillus subtilis 207-25 harboring the recombinant plasmid, p12BS$\Delta$fl$\Delta$PL, revealed increased expression efficiency with chloramphenicol induction when cat-86 was used as a reporter gene.

• 대한수학회논문집
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• 제33권3호
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• pp.1025-1037
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• 2018

We consider an ill-posed problem for the heat equation $u_{xx}=u_t$ in the quarter plane {x > 0, t > 0}. We propose a new method to compute the heat flux $h(t)=u_x(1,t)$ from the boundary temperature g(t) = u(1, t). The operator $g{\mapsto}h=Hg$ is unbounded in $L^2({\mathbb{R}})$, so we approximate h(t) by $h_{\delta}(t)=u_x(1+{\delta},\;t)$, ${\delta}{\rightarrow}0$. When noise is present, the data is $g_{\epsilon}$ leading to a corresponding heat $h_{{\delta},{\epsilon}}$. We obtain an estimate of the error ${\parallel}h-h_{{\delta},{\epsilon}}{\parallel}$, as well as the error when $h_{{\delta},{\epsilon}}$ is approximated by the trapezoidal rule. With an a priori choice rule ${\delta}={\delta}({\epsilon})$ and ${\tau}={\tau}({\epsilon})$, the step size of the trapezoidal rule, the main theorem gives the error of the heat flux as a function of noise level ${\epsilon}$. Numerical examples show that the proposed method is effective and stable.

• Journal of the Korean Statistical Society
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• 제32권3호
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• pp.299-309
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• 2003

Let ${\pi}_1,...,{\pi}_{k}$k($\geq$2) independent logistic populations such that the cumulative distribution function (cdf) of an observation from the population ${\pi}_{i}$ is $$F_{i}\;=\; {\frac{1}{1+exp{-\pi(x-{\mu}_{i})/(\sigma\sqrt{3})}}},\;$\mid$x$\mid$<\;{\infty}$$ where ${\mu}_{i}(-{\infty}\; < \; {\mu}_{i}\; <\; {\infty}$ is unknown location mean and ${\delta}^2$ is known variance, i ＝ 1,..., $textsc{k}$. Let ${\mu}_{[k]}$ be the largest of all ${\mu}$'s and the population ${\pi}_{i}$ is defined to be 'good' if ${\mu}_{i}\;{\geq}\;{\mu}_{[k]}\;-\;{\delta}_1$, where ${\delta}_1\;>\;0$, i = 1,...,$textsc{k}$. A selection procedure based on sample median is proposed to select a subset of $textsc{k}$ logistic populations which includes all the good populations with probability at least $P^{*}$(a preassigned value). Simultaneous confidence intervals for the differences of location parameters, which can be derived with the help of proposed procedures, are discussed. If a population with location parameter ${\mu}_{i}\;<\;{\mu}_{[k]}\;-\;{\delta}_2({\delta}_2\;>{\delta}_1)$, i ＝ 1,...,$textsc{k}$ is considered 'bad', a selection procedure is proposed so that the probability of either selecting a bad population or omitting a good population is at most 1­ $P^{*}$.

• 한국농공학회:학술대회논문집
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• 한국농공학회 2000년도 학술발표회 발표논문집
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• pp.513-518
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• 2000

It has been acknowledged that fertilizer, natural soil nitrogen and animal waste, municipal waste have different mass ratio of nitrogen which is presented as a symbol of $\delta^{15}$N. and that the values of $\delta^{15}$N for fertilizer and natural soil nitrogen and animal waste are placed less than +5$\textperthousand$ and higher than +10$\textperthousand$, respectively. thus, Nitrogen pollution sources and contribution can be interpreted in watershed through $\delta^{15}$N analysis and then, analysis is performed with Kjeldhl-Dumas method. In this study, The values of $\delta^{15}$N are between +1.46$\textperthousand$ and +8.97$\textperthousand$, and the nitrate concentration is placed less than 3.31mg/L and higher than 0.19mg/L, respectively. Thus, this watershed is noncontamination area at the present time. But as a result of $\delta^{15}$N, contribution of natural soil nitrogen be discovered in this watershed, presently.

• 대한수학회논문집
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• 제21권2호
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• pp.261-272
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• 2006

In this paper, we define the sequence spaces: $[V,{\lambda},f,p]_0({\Delta}^r,E,u),\;[V,{\lambda},f,p]_1({\Delta}^r,E,u),\;[V,{\lambda},f,p]_{\infty}({\Delta}^r,E,u),\;S_{\lambda}({\Delta}^r,E,u),\;and\;S_{{\lambda}0}({\Delta}^r,E,u)$, where E is any Banach space, and u = ($u_k$) be any sequence such that $u_k\;{\neq}\;0$ for any k , examine them and give various properties and inclusion relations on these spaces. We also show that the space $S_{\lambda}({\Delta}^r, E, u)$ may be represented as a $[V,{\lambda}, f, p]_1({\Delta}^r, E, u)$ space. These are generalizations of those defined and studied by M. Et., Y. Altin and H. Altinok [7].

• 대한수학회논문집
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• 제10권4호
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• pp.881-887
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• 1995

Let f be a measurable function on the unit ball B in $C^n$, then we define a maximal function $M_p(f), 1 \leq p < \infty$, by $$ M_p(f)(\zeta ) = \sup_{\delta > 0}(\frac{1}{\sigma(\beta(\zeta, \delta))} \int_{T(\beta(\zeta, \delta))} $\mid$f(z)$\mid$^p \frac{d\nu(z)}{(1-$\mid$z$\mid$^n})^{1/p} $$ where $\sigma$ denotes the surface area measure on S, the boundary of B, and $T(\beta(\zeta, \delta))$ denotes the tent over the ball $\beta(\zeta, \delta)$. We prove that the maximal operator $M_p$ belongs to the Muckenhoupt class $A_1$.