• Korean Journal of Fisheries and Aquatic Sciences
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• v.14 no.4
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• pp.269-275
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• 1981

The fishing hooks were tested for breaking and unbending due to plastic deformation of the material. Study of tensile test is not complicated, but has not even worked out fully enough, especially when the test specimen is subjected to plastic deformation. The fishing hook is subjected to unbending stress and the critical section is a Point which is furthest from the line of action of the forces. The dynamic force of fish during jerks depends on their speed of movement and body weight, the kinetic energy corresponding to it and also on the rlastic displacement of the rigging which absorb the energy. Six kinds of hook were tested by the dynamometer under tensile speed 290mm/min (subscript s) and 780mm/min (subscript f). According to their results, the breaking load(B: kg) can be induced with the formula $B={\alpha}wd^2+\beta$ where w(mm) is the distance between the barb base and the lower shank and d(mm) is diameter. The coefficients of the formula for the round hooks(R) and the angular hooks(A) are approximately as follows: $$R:\;\alpha_{s}=0.5,\;\beta_{s}=1.6,\;\alpha_{f}=0.4,\;\beta_{f}=1.4$$ $$A:\;\alpha_{s}=1.1,\;\beta_{s}=2.0,\;\alpha_{f}=1.0,\;\beta_{f}=0.9$$ The ratio of $B_{f}\;to\;B_{s}$ is corresponding to 0.8. The ratio of deformation(X) that is moved distance of barb base at break to the distance(H) between head base and barb base is about $50\%$. Further study should be carried out on the subject of impact and fatigue test under the same condition which is exerted force by the hooked fish.

• Journal of Life Science
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• v.27 no.9
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• pp.1052-1058
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• 2017

Gelidium amansii shows antioxidant and anti-obesity effects; however, the effect on postprandial blood glucose levels is not known. The objective of the present study was to investigate the inhibitory effect of Gelidium amansii extract (GAE) on carbohydrate-digesting enzymes and its ability to alleviate postprandial hyperglycemia in streptozotocin (STZ)-induced diabetic mice. Gelidium amansii was extracted with 80% ethanol and concentrated for use in this study. The ${\alpha}-glucosidase$ and ${\alpha}-amylase$ inhibition assays were performed using the colorimetric method. ICR normal and STZ-induced diabetic mice were orally administered GAE (300 mg/kg body weight) or acarbose (100 mg/kg body weight) alone or soluble starch (2 g/kg body weight). Blood samples were taken from the tail vein at 0, 30, 60 and 120 min. Our results indicated that GAE markedly inhibited ${\alpha}-glucosidase$ and ${\alpha}-amylase$ activities with $IC_{50}$ values of $0.099{\pm}0.009mg/ml$ and $0.178{\pm}0.038mg/ml$, respectively, and was a more effective inhibitor than acarbose, the positive control. Further, the postprandial blood glucose levels of STZ-induced diabetic mice in the GAE-administered group were significantly lower than those of control group mice (p<0.05). Moreover, the area under the curves (AUC) significantly decreased with GAE administration in STZ-induced diabetic mice (p<0.05). These results indicate that GAE may be effective in decreasing postprandial blood glucose levels by inhibiting carbohydrate-digesting enzymes such as ${\alpha}-amylase$ and ${\alpha}-glucosidase$. Therefore, GAE could be used as a potential functional food for alleviating postprandial hyperglycemia.

• Korean Journal of Optics and Photonics
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• v.7 no.3
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• pp.196-199
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• 1996

The amplitude LSF(Line spread function, $C_1e^{{o^2}{x^2}}$ or amplitude impulse) of the Gaussian apodized annular pupil is found to be same to that of the full aperture LSF($C_0e^{{o^2}{x^2}}$). $C_0$ and $C_1$ depending on $\sigma$, ${\omega}_0=\frac{2{\pi}}{\lambda}\;\frac{a_0}{l}$ and ${\omega}_0'=\frac{2{\pi}}{\lambda}\;\frac{a_0'}{l}$ which are the geometric parameter and pupil coordinates of the annular pupil. The important inequality relation among ${\omega}_0,\;{\omega}_0'$, a (fraction of diffraction amplitude) and $\sigma$ is obtained. It is $\frac{{\omega}_0}{\sqrt{2}}<{\sigma}{\le}(\frac{1-a}{2a})^{1/2}\;{\omega}_0$, and in the case of $a=e^{-1},\;a_0'{\le}0.34a_0$. The case of λ=0.013${\mu}{\textrm}{m}$, l=20 cm, $a_0=5cm$ and $a_0=0.34a_0=1.7cm$ give a Gaussian apodized superresolution ${\Delta}=\frac{\sqrt{log2}}{\sigma}=0.008{\mu}m$ annular pupil with the intensity signal equal to $e_{-2}$ times the signal obtainable by using the full aperture system(a=1)

• Journal of applied mathematics & informatics
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• v.34 no.3_4
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• pp.269-284
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• 2016

In this paper, we firstly use Krasnosel'skii fixed point theorem to investigate positive solutions for the following three-point boundary value problems for p-Laplacian with a parameter $({\phi}_P(D^{\alpha}_{0}+u(t)))^{\prime}+{\lambda}f(t, u(t))=0$, 0$D^{\alpha}_{0}+u(0)=u(0)=u{\prime}{\prime}(0)=0$, $u^{\prime}(1)={\gamma}u^{\prime}(\eta)$ where ϕ_p(s) = |s|^p−2s, p > 1, $D^{\alpha}_{0^+}$ is the Caputo's derivative, α ∈ (2, 3], η, γ ∈ (0, 1), λ > 0 is a parameter. Then we use Leggett-Williams fixed point theorem to study the existence of three positive solutions for the fractional boundary value problem $({\phi}_P(D^{\alpha}_{0}+u(t)))^{\prime}+f(t, u(t))=0$, 0$D^{\alpha}_{0}+u(0)=u(0)=u{\prime}{\prime}(0)=0$, $u^{\prime}(1)={\gamma}u^{\prime}(\eta)$ where ϕ_p(s) = |s|^p−2s, p > 1, $D^{\alpha}_{0^+}$ is the Caputo's derivative, α ∈ (2, 3], η, γ ∈ (0, 1).

• YAKHAK HOEJI
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• v.36 no.4
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• pp.390-396
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• 1992

Streptomyces minoensis DMCJ-144 isolated from soil produces the ${\alpha}-amylase$ inhibitor. Optimum culture conditions for ${\alpha}-amylase$ inhibitor production of the strain were determined in this experiment. The optimum composition of the culture medium was studied by supplementing various carbon sources, nitrogen sources, vitamins, and metal salts to the basal medium containing 1% glucose, 0.1% asparagine, 0.005% $MgSO_4{\cdot}7H_2O$, 0.005% $K_2HPO_4$, 0.005% NaCl. Other culture conditions such as the culture temperature, initial pH of the medium, aeration, and culture time were also investigated. When the strain was cultured in a 100 ml flask containing 20 ml of 2% glucose, 0.5% beef extract, 0.0002% riboflavin, 0.0002% thiamine HCI, 0.01% $ZnCl_2$, 0.005% $MgSO_4{\cdot}7H_2O$, 0.005% $CuSO_4{\cdot}5H_2O$, 0.005% NaCl, pH 7.2, 180 rpm at $30^{\circ}C$, the maximum production of the ${\alpha}-amylase$ inhibitor was observed after 5 days of the cultivation.

• Preventive Nutrition and Food Science
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• v.22 no.3
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• pp.166-171
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• 2017

In this study, we investigated whether Sargassum yezoense extract (SYE) could inhibit ${\alpha}-glucosidase$ and ${\alpha}-amylase$ activities, and alleviate postprandial hyperglycemia in streptozotocin (STZ)-induced diabetic mice. Freeze-dried S. yezoense was extracted with 80% ethanol and concentrated for use in this study. The hypoglycemic effect was determined by evaluating the inhibitory activities of SYE against ${\alpha}-glucosidase$ and ${\alpha}-amylase$ as well as its ability to decrease postprandial blood glucose levels. The half-maximal inhibitory concentrations of SYE against ${\alpha}-glucosidase$ and ${\alpha}-amylase$ were $0.078{\pm}0.004$ and $0.212{\pm}0.064mg/mL$, respectively. SYE was a more effective inhibitor of ${\alpha}-glucosidase$ and ${\alpha}-amylase$ activities than the positive control, acarbose. The increase in postprandial blood glucose levels was significantly alleviated in the SYE group compared with that in the control group of STZ-induced diabetic mice. Furthermore, the area under the curves significantly decreased with SYE administration in STZ-induced diabetic mice. These results suggest that SYE is a potent inhibitor of ${\alpha}-glucosidase$ and ${\alpha}-amylase$ activities and alleviates postprandial hyperglycemia caused by dietary carbohydrates.

• Proceedings of the KSRS Conference
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• 2009.03a
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• pp.280-285
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• 2009

1998년 8월부터 2005년 6월까지 한반도 주변 해역에서 현장관측한 해수의 고유 광특성(IOPs)과 외형적 광특성(AOPs) 자료들을 이용하여 원격반사도$(R_{rs}(\lambda))$와 성분별 흡광계수의 총 합 $(\alpha(\lambda)=\alpha_w(\lambda)+\alpha_{ph}(\lambda)+\alpha_{ss}(\lambda)+\alpha_{dom}(\lambda))$의 상관관계를 분석하고, $R_{rs}(\lambda)$ 밴드비를 이용하여 흡광계수 산출 알고리즘을 개발하였다. 파장에 따른 $R_{rs}(\lambda)$와 총합 $\alpha(\lambda)$의 상관관계는 반비례적인 관계를 보였고, 파장 443 nm일 때 상관도$(R^2)$는 0.717이다. $\alpha_{ph}(\lambda)$ 산출알고리즘은 엽록소의 흡광과 관련된 파장 490 nm와 부유물의 산란과 관련된 파장 555 nm의 $R_{rs}(\lambda)$ 밴드비의 함수 형태로 구성하였고, 파장 443 nm일 때 RMS 값은 0.223이다. $\alpha_{ss}(\lambda)$과 $\alpha_{dom}(\lambda)$ 산출 알고리즘은 용존유기물의 흡광과 관련된 파장 412 nm와 부유물의 산란과 관련된 파장 555 nm의 $R_{rs}(\lambda)$ 밴드비의 함수 형태로 구성하였고, 파장 412 nm일 때 RMS 값은 각각 0.324와 0.230이다. $\alpha_{ph}(\lambda),\;\alpha_{ss}(\lambda),\;\alpha_{dom}(\lambda)$ 산출 알고리즘들은 대체적으로 현장값보다 높게 추정하였고 스펙트럼들은 잘 재현해냈다. 추후 이에 대한 개선과 알고리즘의 검보정이 요구된다.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.12 no.4
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• pp.406-412
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• 2019

In this paper, we propose two algorithms for classifying services with similar delay characteristics into three classes and allocating radio resources according to priority in LTE-A system where H2H and M2M services coexist. The first is to allocate resources from the higher priority class to the lower priority class, and each class gives priority to H2H over M2M, and the other is to give priority to H2H regardless of delay characteristics except for the class with the highest priority. The RA success probability was analyzed according to the access rate(${\alpha}$) of M2M devices in each class. In comparison with the conventional systems, it was improved from 0.5 to 0.52 for ${\alpha}_{2M}=0.05$ in two classes. In the three classes, the success probability was slightly increased from 0.5 to 0.57 for ${\alpha}_{2M}={\alpha}_{3M}=1$ and from 0.5 to 0.58 for ${\alpha}_{2M}=0.5$ and ${\alpha}_{3M}=0.1$. Although 6 services are considered in the proposed scheme, the RA success probability is almost similar to the previous scheme because the average arrival rate of H2H of each class is set to the same.

• Journal of the Chungcheong Mathematical Society
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• v.22 no.4
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• pp.727-737
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• 2009

Let M(X) be the space of all pointwise multipliers of Banach space X. We will show that, for each $\alpha>1$, $M(\mathfrak{B}_\alpha)=M(\mathfrak{B}_{\alpha,0})=H^\infty{(B)}$. We will also show that, for each $0<{\alpha}<1$, $M(\mathfrak{B}_\alpha)$ and $M(\mathfrak{B}_{\alpha,0})$ are Banach algebras. It is established that certain inclusion relationships exist between the weighted Bloch spaces and holomorphic Besov spaces.

• 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.