• IE interfaces
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• v.13 no.4
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• pp.738-744
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• 2000

This Paper presents a method for unfinished work transition probability distribution of modulated $n^*D/D/l$ queue with overload period. The Modulated $n^*D/D/l$ queue is well known as a performance analysis model of ATM multiplexer with superposition of homogeneous periodic on-off traffic sources. Theory of probability by conditioning and results of $N^*D/D/l$ queue are used for analytic methodology. The results from this paper are expected to be applied to general modulated $n^*D/D/l$ queue.

• Journal of Food Hygiene and Safety
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• v.35 no.1
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• pp.23-30
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• 2020

This study investigated the migration levels of lead (Pb), cadmium (Cd), and arsenic (As) from food contact articles (glassware, ceramics, enamelware, and earthenware) into a food stimulant (4% v/v, acetic acid). Migration tests were performed at 25℃ for 24 h and all analyses were performed using Inductively-Coupled Plasma Mass Spectrometry (ICP-MS). The method was validated by linearity of calibration curves, limit of detection (LOD), limit of quantification (LOQ), recovery, precision, and uncertainty. In glassware, the migration concentrations ranged from not-detected (N.D.) to 752.21 ㎍/L and N.D. to 1.99 ㎍/L for Pb and Cd, respectively. In ceramics, the migration concentrations ranged from N.D. to 1,955.86 ㎍/L, N.D. to 74.06 ㎍/L, and N.D. to 302.40 ㎍/L for Pb, Cd, and As, respectively. In enamelware, the migration concentrations ranged from N.D. to 4.48 ㎍/L, N.D. to 7.00 ㎍/L, and N.D. to 52.00 ㎍/L for Pb, Cd, and Sb, respectively. In earthenware, the migration concentrations ranged from N.D. to 13.68 ㎍/L, N.D. to 0.04 ㎍/L, and N.D. to 6.71 ㎍/L for Pb, Cd, and As, respectively. All results were below the migration limits of Korea standards and specifications for food utensils, containers, and packages.

• Journal of the Korean Mathematical Society
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• v.32 no.1
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• pp.141-149
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• 1995

Let N denote the set of positive integers. Fix $d_1, d_2 \in N with d = d_1 + d_2$. Let X and Y be real random variables and let ${X_i : i \in N^d_1} and {Y_j : j \in N^d_2}$ be independent families of independent identically distributed random variables with $L(X) = L(X_i) and L(Y) = L(Y_j)$, where $L(\cdot)$ denote the law of $\cdot$.

• Transactions of the Korean Society of Mechanical Engineers
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• v.2 no.3
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• pp.53-61
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• 1978

This study has been concentrated on the relations between the crack growth rate and the stress intensity factor, the fatigue limit and finally on the condition of the crack propagation along the laminated cross section of the laminated steel under the repeated plane bending through tests. The following results are obtained. 1. The fatigue limit of the laminated steel is higher than the single steel 2. The realtion between the fatigue crack growth rate, dL/dN and Stress intensity factor are ; dL/dN = 2.14 * 10$^{-11}$ $K^{2.95}$ for SUP 9 dL/dN = 1.70 * 10$^{-11}$ $K^{2.95}$ for SMS dL/dN = 9.77 * 10$^{-11}$ $K^{2.95}$ for SPMS dL/dN = 3.57 * 10$^{-8}$ $K^{1.53}$ for SPMM dL/dN = 5.5O * 10$^{-8}$ $K^{1.53}$ for MLD 3. The crack propagation of the laminated steel also tends to be completed through 3 steps; The first step proceeds swiftly, in a second slowly for a long time and last very rapidly for a short moments.

• Bulletin of the Korean Chemical Society
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• v.33 no.11
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• pp.3793-3796
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• 2012

A novel 3D compound $\{[Cu(L)(H_2O)_4][Cu_2(SIP)_2(L)_2]\}{\cdot}2H_2O$ (1) (L = N,N-bis(4-pyridinecarboxamide)-1,4-butane, SIP = 5-sulfoisophthalate) is hydrothermally synthesized. X-ray diffraction analysis reveals that compound 1 is composed of 2D anionic $[Cu_2(SIP)_2(L)_2]_n{^{2n-}}$ double-layers and discrete 1D cationic $[CuL(H_2O)_4]_n{^{2n+}}$ polymeric chains, which represents a rare 3D polypseudo-rotaxane MOF from intercalation of 1D and 2D framework. In addition, the luminescent property and electrochemical behavior of compound 1 have been investigated.

• Journal of the Korean Mathematical Society
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• v.54 no.4
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• pp.1301-1316
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• 2017

It is well known that every $x{\in}(0,1]$ can be expanded to an infinite $L{\ddot{u}}roth$ series with the form of $$x={\frac{1}{d_1(x)}}+{\cdots}+{\frac{1}{d_1(x)(d_1(x)-1){\cdots}d_{n-1}(x)(d_{n-1}(x)-1)d_n(x)}}+{{\cdots}}$$, where $d_n(x){\geq}2$ for all $n{\geq}1$. In this paper, the set of points with some restrictions on the digits in $L{\ddot{u}}roth$ series expansions are considered. Namely, the Hausdorff dimension of following the set $$F_{\phi}=\{x{\in}(0,1]\;:\;d_n(x){\geq}{\phi}(n),\;i.o.n}$$ is determined, where ${\phi}$ is an integer-valued function defined on ${\mathbb{N}}$, and ${\phi}(n){\rightarrow}{\infty}$ as $n{\rightarrow}{\infty}$.

• KSBB Journal
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• v.8 no.1
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• pp.10-16
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• 1993

The use of Jerusalem artichoke containing $\beta$-1, 2-fructose oligomer for the production of D-sorbitol and L-sorbose has been studied. The employment of inulinase(0.398%, v/v) for the hydrolysis of 40% (v/w) Jerusalem artichoke juice resulted in 36.7g/1 of glucose and 85.3g/1 of fructose at $50^{\circ}C$. These sugars were utilized as substrates for D-sorbitol and L-sorbose production. Coimmobilization of inulinase and permeabilized cells of Zymomonas mobilis in the mixture of chitin (5%, w/e) and x-carrageenan(4%, w/v) resulted in the production of 30.2g/1 of D-sorbitol by using inulin as a substrate. The process of L-sorbose production from D-sorbitol by Gluconobacter suboxydans was optimized with respect to the substrate concentration, level of dissolved oxygen and glucosic and concentration. Gluconlc acid produced by Zymomonas mobilis from glucose was found to inhibit Gluconobacter suboxtans in conversion of D-sorbitol to L-sorbose. In view of removing such inhibitory effect by gluconic acid, mutants were selected by the NTG (N-methyl-N'-N'-nitro-N-nitrosoguanidlne) treated method. Mutants selected by NTG mutagenesis showed no inhibitory effects of gluconic acrid against L-sorbone production when its concentration increased up to 100g/1. A mutant produced 40.1g/l of L-sorbose in the medium containing 100g/l D-sorbitol and 100g/l-gluconic acid. This result is consider able when compared with L-sorbose concentration (21.7g/1) obtained from the fermentation with wild type strain of Gluconobacter suboxnians.

• Journal of Ginseng Research
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• v.24 no.2
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• pp.89-93
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• 2000

WB were screening the stele and the cortex of the ginseng roots (Panax ginseng C.A.Meyer) on the exo-0-glycosylhydrolase activities during vegetation period of 1999 year. The following p-nitrophenylglycosides were used to test exe-0-glycosylhydrolase activities: $\alpha$- and $\beta$-D-galactopyranosides,$\alpha$- and $\beta$-D-glucopyranosides, $\alpha$- and $\beta$-D-mannopyranosides, N-acetyl-$\beta$-D-glucosaminide, $\alpha$- and $\beta$-D-xylopyranosides $\alpha$- L-rhamnopyranoside, $\beta$-D-glucuronide, $\beta$-D-galacturonide, $\beta$-L-,$\alpha$-L- and $\beta$-D-fucopyranosides, $\alpha$-L-arabinopyranoside. Only $\beta$-D-galactosidase, $\alpha$-L-mannosi-dase , N- acetyl- ${\beta}$-D-slucosarninidase, $\alpha$-D-galacto sidase, $\alpha$-L-arabinosidase, and $\beta$-D-fuco sidase were found in both partsof ginseng roots. Their contents during the vegetation period were shown to differ considerably, being dependent not only on plant development stage but on plant tissue and environmental conditions too.

• Journal of the Korean Society of Propulsion Engineers
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• v.9 no.4
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• pp.31-38
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• 2005

In this paper, the combustion characteristics of a hybrid propulsion system were studied with various L/D(length vs diameter) ratio of the single po.1 type solid fuel. Experiments were performed for 2 cases with the fixed grain port diameter and fuel length respectively. For the first case, results show that there are no large variations for regression rates as the L/D ratio changes. And as the L/D ratio increases, the O/F ratio decreases and thrust, characteristic velocity tends to increase. For the second case, there is no large change for O/F ratio, thrust and characteristic velocity as L/D ratio changes. On the other hand, as the L/D ratio decreases, only the regression rate tends to increase. Experimentally, exponent n in $\dot{r}=a{G_0}^n$ was found about 0.5 and then the O/F ratio was shown nearly constant. In the experiment, PE and gas oxygen were used as a fuel and an oxidizer.

• Bulletin of the Korean Mathematical Society
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• v.43 no.1
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• pp.125-140
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• 2006

Let $g(n,\;l_1,\;l_2,\;d,\;t,\;q)$ be the number of general4-regular graphs on n labelled vertices with $l_1+2l_2$ loops, d double edges, t triple edges and q quartet edges. We use inclusion and exclusion with five types of properties to determine the asymptotic behavior of $g(n,\;l_1,\;l_2,\;d,\;t,\;q)$ and hence that of g(2n), the total number of general 4-regular graphs where $l_1,\;l_2,\;d,\;t\;and\;q\;=\;o(\sqrt{n})$, respectively. We show that almost all general 4-regular graphs are 2-connected. Moreover, we determine the asymptotic numbers of general 4-regular graphs with given connectivities.