• Bulletin of the Korean Chemical Society
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• v.2 no.3
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• pp.96-104
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• 1981

(1) The flow data of f (stress) and ${\dot{s}$ (strain rate) for Fe and Ti alloys were plotted in the form of f vs. -ln ${\dot{s}$ by using the literature values. (2) The plot showed two distinct patterns A and B; Pattern A is a straight line with a negative slope, and Pattern B is a curve of concave upward. (3) According to Kim and Ree's generalized theory of plastic deformation, pattern A & B belong to Case 1 and 2, respectively; in Case 1, only one kind of flow units acts in the deformation, and in Case 2, two kinds flow units act, and stress is expressed by $f={X_1f_1}+{X_2f_2}$where $f_1\;and\;f_2$ are the stresses acting on the flow units of kind 1 and 2, respectively, and $X_1,\;X_2$ are the fractions of the surface area occupied by the two kinds of flow units; $f_j=(1/{\alpha}_j) sinh^{-1}\;{\beta}_j{{\dot{s}}\;(j=1\;or\;2)$, where $1/{\alpha}_j\;and\;{\beta}_j$ are proportional to the shear modulus and relaxation time, respectively. (4) We found that grain-boundary flow units only act in the deformation of Fe and Ti alloys whereas dislocation flow units do not show any appreciable contribution. (5) The deformations of Fe and Ti alloys belong generally to pattern A (Case 1) and B (Case 2), respectively. (6) By applying the equations, f=$(1/{\alpha}_{g1}) sinh^-1({\beta}_{g1}{\dot{s}}$) and $f=(X_{g1}/{\alpha}_{g1})sinh^{-1}({\beta}_{g1}{\dot{s}})+ (X_{g2}/{\alpha}_{g2})\;shih^{-1}({\beta}_{g2}{\dot{s}})$ to the flow data of Fe and Ti alloys, the parametric values of $x_{gj}/{\alpha}_{gj}\;and\;{\beta}_{gs}(j=1\;or\;2)$ were determined, here the subscript g signifies a grain-boundary flow unit. (7) From the values of ($({\beta}_gj)^{-1}$) at different temperatures, the activation enthalpy ${\Delta}H_{gj}^{\neq}$ of deformation due to flow unit gj was determined, ($({\beta}_gj)^{-1}$) being proportional to , the jumping frequency (the rate constant) of flow unit gj. The ${\Delta}H_{gj}\;^{\neq}$ agreed very well with ${\Delta}H_{gj}\;^{\neq}$ (self-diff) of the element j whose diffusion in the sample is a critical step for the deformation as proposed by Kim-Ree's theory (Refer to Tables 3 and 4). (8) The fact, ${\Delta}H_{gj}\;^{\neq}={\Delta}H_{j}\;^{\neq}$ (self-diff), justifies the Kim-Ree theory and their method for determining activation enthalpies for deformation. (9) A linear relation between ${\beta}^{-1}$ and carbon content [C] in hot-rolled steel was observed, i.e., In ${\beta}^{-1}$ = -50.2 [C] - 40.3. This equation explains very well the experimental facts observed with regard to the deformation of hot-rolled steel..

• Journal of Applied Biological Chemistry
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• v.58 no.1
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• pp.5-8
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• 2015

This study was to isolate an active component of the chloroform fraction from the methanol extract of Ruta chalepensis leaves and to measure inhibitory effects against ${\alpha}$-glucosidase or ${\alpha}$-amylase. The inhibitory compound of R. chalepensis leaves was isolated using chromatographic methods and identified as quinoline. Quinoline and its structurally related derivatives were tested for their inhibitory activities by evaluating the $IC_{50}$ values against ${\alpha}$-amylase or ${\alpha}$-glucosidase and were compared with that of acarbose. Based on the $IC_{50}$ values, quinazoline exhibited the greatest inhibitory activity ($20.5{\mu}g/mL$), followed by acarbose ($66.5{\mu}g/mL$), and quinoline ($80.3{\mu}g/mL$) against ${\alpha}$-glucosidase. In case of ${\alpha}$-amylase, quinazoline had potent inhibitory activity, followed by quinoline ($179.5{\mu}g/mL$) and acarbose ($180.6{\mu}g/mL$). These results indicate that R. chalepensis extract, quinoline, and quinazoline could be useful for inhibiting ${\alpha}$-glucosidase or ${\alpha}$-amylase.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.23 no.5
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• pp.110-119
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• 2009

In this study magnetic fields near electric power lines with branch lines which have a arbitrary angle were derived and formulated by dipole antenna theory and could be calculated easily using the formula. It seems that those formula could be applicable to the consideration of magnetic fields during the design of distribution lines with branch lines. As an example those formulated equations on elements of magnetic fields were applied to a model of 3 phase distribution lines with branch lines and calculated by Matlab programs and the results were presented The analyzed results are follows. The resultant magnetic field is dominated by the componant By all over y-axis in the case of the smaller branched angle $\alpha$ and the lower observed point z. In case of ${\alpha}=\frac{\pi}{2}$[rad], the resultant field is affected by the componant Bx. The resultant field is dominated by the componant Bz at the vicinity of the power lines and it shows very large value at the branch line position of y-axis in case of ${\alpha}>\frac{\pi}{2}$.

• Journal of Veterinary Clinics
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• v.20 no.4
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• pp.478-481
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• 2003

Canine juvenile cellulitis (CJC) is a well-recognized lymphocutaneous disease that is seen in young dogs. CJC seemed to be immunologic disorder and may have a hereditary aspect. Exact pathogenesis and cytokine regulation on the immune system of CJC are not clear. CJC was diagnosed in two puppies hospitalized in Veterinary Teaching Hospital of Chungbuk National University. To investigate the cytokine regulation on CJC, RT-PCR was performed with CJC affected dogs. RT-PCR 1 was performed with whole blood sample (CJC-B) and fine needle aspirates of the inguinal lymph node (CJC-LN) from case 1-dog, which included $TNF-\alpha,$ $IL-1\beta,$ $IFN-\gamma,$ IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, IL-12 and $\beta-actin.$ Blood sample from a normal dog (N-B) served for a negative control of RT-PCR 1 (case 1). $IFN-\gamma,$ IL-2, IL-4, IL-5, IL-8, IL-10 and IL-12 transcripts were not expressed in all sample. $TNF-\alpha$ and $IL-1\beta,$ were not transcripted from CJC-B but from CJC-LN. On RT-PCR 2 (case 2), submandibular lymph node aspirates were used and $TNF-\alpha,$ IL-10, $IFN-\gamma$ and $IL-1\beta$ were expressed. $TNF-\alpha,$ 1L-10 and $IFN-\gamma$ were secreted from activated macrophages enhance the inflammation in tissue. These results imply that abnormally increased macrophages secret $TNF-\alpha$ and $IL-1\beta$ in the affected lymph nodes, which attract neutrophils and cause inflammation in CJC.

• Tunnel and Underground Space
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• v.7 no.4
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• pp.334-340
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• 1997

Alpha center theory which was first proposed by Stefanescu has been proved to be effective for the detection of the location of the conductive orebody. A numerical forward modeling was conducted to verify the effectiveness of this method. Field works were carried out along the three profiles in two different areas for the purpose of finding fractured zone which might be accompanied with the presence of the groundwater. And the results were modeled by alpha center method, which was later testified by wellproven 2-dimensional finite difference inversion scheme. Field data could be successfully modeled with this alpha center algorithm, especially for the smooth-varying resistivity models. For the abrupt change of the resistivity values, the alpha center coefficients have a tendency to be negative to simulate the steep resistivity gradients. This method is quite simple and easy for the future applications. The numerical calculation can be performed very quickly with the personal computers.

• Journal of the Korean Mathematical Society
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• v.57 no.4
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• pp.1019-1030
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• 2020

Efficient computation of r-th root in 𝔽_q has many applications in computational number theory and many other related areas. We present a new r-th root formula which generalizes Müller's result on square root, and which provides a possible improvement of the Cipolla-Lehmer type algorithms for general case. More precisely, for given r-th power c ∈ 𝔽_q, we show that there exists α ∈ 𝔽_q^r such that $$Tr{\left(\begin{array}{cccc}{{\alpha}^{{\frac{({\sum}_{i=0}^{r-1}\;q^i)-r}{r^2}}}\atop{\text{ }}}\end{array}\right)}^r=c,$$ where $Tr({\alpha})={\alpha}+{\alpha}^q+{\alpha}^{q^2}+{\cdots}+{\alpha}^{q^{r-1}}$ and α is a root of certain irreducible polynomial of degree r over 𝔽_q.

• Bulletin of the Korean Mathematical Society
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• v.24 no.1
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• pp.13-17
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• 1987

Let S denote the class of nivalent functions normalized so that f(0)=f'(0)-1=0 in vertical bar z vertical bar <1. Let $S_{\alpha}$$^{*}$, -.pi./2<.alpha.<.pi./2, denote the subclass of S that satisfies Re $e^{i{\alpha}}$zf'(z)/f(z).geq.0 in vertical bar z vertical bar <1; then f is called .alpha.-spiral-like and the case .alpha.=0 is the class of normalized starlike functions [6, pp.52]. Let T denote the class of functions f normalized as above and satisfying Im z[Im f(z)]..geq.0 in vertical bar z vertical bar <1; then f is called typically real and T contains those functions of S whose coefficients are real [6, pp.55]. Also, in view of [6, pp.231], let B(.lambda.) be the class of function normalized as above and map vertical bar z vertical bar <1 onto the complement of an arc with radial angle .lambda.(0<.lambda.<.pi./2). The radial angle is meant to be the angle between the tangent and radial vectors to the arc. This note includes a sharp version for Corollary 1 of [2] when f.mem. $S_{\alpha}$$^{*}$ as well as a logarithmic coefficient estimate.nt estimate.

• Transactions of the Korean hydrogen and new energy society
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• v.7 no.1
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• pp.11-18
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• 1996

The Laves phase alloy hydrides have some promising properties as electrode materials in reversible metal hydride batteries. In this work, the hydrogen storage performance, crystallographic parameters, surface morphology, surface area and electrochemical characteristics of the non-stoichiometric $ZrMn_{0.3}V_{0.7}Ni_{1.4+{\alpha}}$, $ZrMn_{0.5}V_{0.5}Ni_{1.4+{\alpha}}$($\alpha$ =0.0, 0.2, 0.4, 0.6) alloys were examined. These as-cast alloys were found to have mainly a cubic C15-type Laves phase structure by X -ray diffraction analysis. The equilibrium pressure of the alloy were increased as $\alpha$ increased in both two types alloy. In case of $ZrMn_{0.5}V_{0.5}Ni_{1.4+{\alpha}}$ alloys, discharge efficiency and the rate capability of the alloy were decreased as $\alpha$ increased but, these values were increased in case of $ZrMn_{0.3}V_{0.7}Ni_{1.4+{\alpha}}$ alloys. The differences of these electrode properties observed were dependent on the reaction surface area and the catalytic activity of unit area of the each electrode.

• Journal of The Korean Society of Clinical Toxicology
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• v.6 no.1
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• pp.52-56
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• 2008

Amitraz is used as farm-animal insecticide. Its side effects in humans are related to its pharmacological activity on alpha 2-adrenergic receptors. The case describes a previously healthy 46-year-old woman who intentionally ingested approximately 250mL of liquid amitraz. She presented with vomiting, altered mental status, miosis, dry mouth, hypopnea, metabolic and respiratory acidosis, hypotension, hypothermia, polyuria, metabolic acidosis, elevated serum aminotransferase and abdominal distension. Supportive treatments including mechanical ventilation, hydration, dopamine infusion, bicarbonate infusion and gastric decompression resulted in improvement. By hospital day 3, she recovered with resolution of abdominal distension. It is paramount to recognize amitraz poisoning when a pesticide-intoxicated patient presets with signs and symptoms consistent with organophosphate intoxicated patients but with greater alpha 2-adrenergic related symptoms such as decreased bowel motility and xerostomia.

• Korean Journal of Materials Research
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• v.9 no.2
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• pp.111-116
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• 1999

The microstructure of vitreous bonded abrasives, which are used as the essential materials in the precise grinding, was investigated theoretically using two particle model. In this paper, a general equation applicable for a case in which there is a gap between abrasive grits is suggested. As a result, it was known that both the volume ratio of grit to glassy bond(V\ulcorner/V\ulcorner) and porosity(V\ulcorner) are the function of $\alpha$(the ratio of distance between grit to diameter of grit) and $\theta$(the angle from the center of pore to that of grit). Because the value $\alpha$ and $\theta$ can be get easily by using these suggested equations, the microstructure could be explained quantitatively. Also the raised error with the increasing amount of bond was modified by the simple assumption. As a result, in that case, both V\ulcorner/V\ulcorner and V\ulcorner were known to be the function of $\alpha$ and $\theta$(the ratio diameter of pore to that of grit).