• Communications of the Korean Mathematical Society
• /
• v.19 no.4
• /
• pp.701-713
• /
• 2004

We obtain the Hyers-Ulam-Rassias stability of a betatype functional equation $f(\varphi(x),\phi(y))$ = $ \psi(x,y)f(x,y)+ \lambda(x,y)$ with a restricted domain and the stability in the sense of R. Ger of the equation $f(\varphi(x),\phi(y))$ = $ \psi(x,y)f(x,y)$ with a restricted domain in the following settings: $g(\varphi(x),\phi(y))-\psi(x,y)g(s,y)-\lambda(x,y)$\mid$\leq\varepsilon(x,y)$ and $\frac{g(\varphi(x),\phi(y))}{\psi(x,y),g(x,y)}-1 $\mid$ \leq\epsilon(x,y)$.

• Bulletin of the Korean Chemical Society
• /
• v.19 no.10
• /
• pp.1068-1072
• /
• 1998

We present results of molecular dynamic (MD) simulations for the segmental motion of liquid n-butane as the base case for a consistent study for conformational transition from one rotational isomeric state to another in long chains of liquid n-alkanes. The behavior of the hazard plots for n-butane obtained from our MD simulations are compared with that for n-butane of Brownian dynamics study. The MD results for the conformational transition of n-butane by a Poisson process form the total first passage times are different from those from the separate t-g and g-t first passage times. This poor agreement is probably due to the failure of the detailed balance between the fractions of trans and gauche. The enhancement of the transitions t-g and g-t at short time regions are also discussed.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.26 no.11
• /
• pp.1672-1678
• /
• 2022

In this paper, the relay antenna was designed in consideration of the performance of the 28GHz band 5G mobile communication relay horn antenna, such as radiation pattern and return loss. A horn array for 5G mobile communication repeater was designed by arranging the antenna elements in phase, and the performance was analyzed. Unlike conventional WCDMA (3G) and LTE (4G), in millimeter wave band communication, high path loss occurs between transmission and reception. In the design of a 5G millimeter wave horn antenna, antenna performance such as isolation and gain between antenna elements as well as gain and bandwidth of the antenna must be additionally considered. The antenna gain of the single horn antenna (1×1) and the array horn antenna (2×4) in the 28GHz band is about 10.44d Bi and 19.58dBi, respectively, and the return loss is designed to be less than -18dB. It has proven its validity and has been shown to be suitable for application to 5G mobile communication relay system.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.25 no.5
• /
• pp.846-854
• /
• 1996

High dietary fiber(DF) diets lower blood glucose and insulin requirements in diabetics. In this study we evaluated the effects of high dietary fiber(DF) food supplements on glucose metabolism in thirty-four subjects with non-insulin-dependent diabetes mellitus(NIDDM). The subjects were divided into three test groups. Each group's prescribed hospital diets were augmented by one of the three following DF supplements for two weeks: Soybean biscuits containing 5g of total DF-the control group(n=15); Biji biscuits containing 20g of total DF-the high insoluble DF group(n=9); and sea tangle biscuits containing 25g of total DF-the high soluble DF group(n=10). The mean daily DF intake of the subjects during the period were: $19.1\pm4.3g$ for the soybean control group; $32.5\pm4.1g$ for the Bijl group; and $38.1\pm5.5g$ for the sea tangle group. The supplementation of the Biji or sea tangle biscuits singnificantly lowered fasting serum glucose levels(p < 0.05) and resulted in the improvement of glucose tolerance. However, the secretions of insulin, C-peptide, and glucagon and Hb $A_{lc}$ concentration were not affected by the high fiber supplementary feeding for two weeks. The urinary excretion of glucose decreased remarkably after the addition of the DF supplements in all three groups(p<0.05). The results indicate that the supplementation of Biji or sea tangle bascuits possesses a beneficial effect on the improvement of glucose metabolism in subjects with NIDDM.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.39 no.7
• /
• pp.986-991
• /
• 2010

This study was conducted to investigate the changes of mineral, oxalate and phytate during tofu processing with Korean recommended soybean cultivars. Fourteen cultivars were selected by distribution of calcium, oxalate and phytate contents. Tofu was manufactured and analyzed for quality characteristics, mineral, oxalate and phytate contents. The yield and moisture contents of tofu ranged from 137.77% in Anpyeongkong to 201.91% of Geomjeongkong 4, and 74.42 (Bongeuikong)~80.01% (Hojangkong), respectively. The lightness (L-value), redness (a-value) and yellowness (b-value) ranged from 53.05 (Dawonkong) to 86.16 (Jipumkong 2), -2.04~5.85, and from 3.28 in Geomjeongkong 4 to 16.17 of Cheongjakong, respectively. The hardness of tofu with selected soybean cultivar ranged from 537.36 g (Dongpuktae) to 1696.05 g (Jinpumkong 2). The highest calcium content was 1.488 mg/g in Dawonkong, oxalate and phytate in tofu were high at 0.40 mg/g in Geomjeongkong 4 and 0.41 mg/g in Dawonkong, respectively. The transfer ratios of oxalate and phytate from soybean to tofu were ranged from 0.31~19.70 and 0.41~19.70%, respectively.

• Korean Journal of Food Science and Technology
• /
• v.48 no.3
• /
• pp.256-261
• /
• 2016

This study investigated the changes in functional components of barley powder produced from different grain varieties (Dahan, Hinchalssalbori, Heukgwang, Huknuri and Boseokchal) and varying milling degrees (27, 23, 19, and 15%). Total polyphenol contents increased with a decrease in the milling degree, with content ranges of 0.97-1.40, 1.19-1.66, 1.22-1.77, 1.30-1.93, and 1.46-2.12 mg/g, respectively. Total flavonoids content also increased with a decrease in the milling degree. The total polyphenol and flavonoids contents were the highest in barley powder from Huknuri and Boseokchal grains. Total dietary fiber, arabinoxylan, and GABA contents increased with a decrease in the milling degree. As the milling degrees decreased, ${\beta}$-glucan contents, which was the highest in Hinchalssalbori and Boseokchal, decreased with ranges of 4.98-7.29, 5.26-7.03, 4.84-7.17, 4.84-700, and 4.66-6.33 mg/100 g, respectively. These results provide useful data for selection of an appropriate variety and milling degree to achieve a high quality in barley processing.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.12 no.10
• /
• pp.4378-4384
• /
• 2011

In order to evaluate the anti-oxidative capabilities of Angelica dahurica Radix ethanol extract (ADEE), we analyzed the contents of polyphenol and flavonoid compounds and the electron donating ability from ADEE. For animal experimentation, the test agent was topically applied to the artificial tanning spots which were induced by 1,500 mJ/$cm^2$ of ultraviolet B radiation on the backs of brown guinea pigs weighing approximately 450~500g. The test agent of $30{\mu}{\ell}$ was applied (6areas per group) twice a day, five days a week, for five weeks. On completion of the experiment, the animals were sacrificed under anesthetization, and the artificial tanning spots were obtained by biopsy punch and stained with H&E to observe the histological change in the epidermis and dermis. As a result, the contents of polyphenol and flavonoid compounds in ADEE were 20.7mg/g and 19.5mg/g respectively. As the for electron-donating capability of ADEE, it was observed that ADEE displays a dose-dependent antioxidative capacity of 14.8% and 19.8% at the concentration of 500 and 1000 ${\mu}g/m{\ell}$ respectively. Tissue staining with H&E revealed that the epidermis of the control group was slightly thicker than that of the other groups. However no inflammation or any other undesirable effect on the skin tissue due to ADEE was observed. These results indicate that ADEE is of value as a natural antioxidant.

• Journal of Animal Environmental Science
• /
• v.9 no.1
• /
• pp.19-26
• /
• 2003

This study was carried out to investigate the collecting efficiency of cyclone deduster installed in weaned piglet building in third weeks of age. There are two peaks of high level of dust concentration in piglet house at the time of 09:00~10:00(5,322$\mu g/m^3$) and 19:00~20:00(6,763$\mu g/m^3$), but the peaks of dust concentration in the building used cyclone deduster was decreased to 3,614.8 and 2,229.5$\mu g/m^3$, respectively. Collecting efficiency of total suspended particulate(TSP), particulate matter less than 10$\mu\textrm{m}$(PM 10) and particulate matter less than 2.5$\mu\textrm{m}$(PM 2.5) in weaned piglet building used in cyclone deduster was 38.3%, 32.5, 21.8, respectively. Aerial dust in weaned piglet building by number basis in the range of 0.745~1.08$\mu\textrm{m}$ was 53.5%. But dust distribution over 10$\mu\textrm{m}$ in volume basis was 82.8% and 86.2%. Crude protein of dust was 25.9~32.7%, and it was higher than feed crude protein(22.0%). Heavy metal concentration of dust was also high level compare to that of feed.

• Korean Journal of Mathematics
• /
• v.19 no.4
• /
• pp.367-379
• /
• 2011

In this paper, we find the maximum exponent of primitive simple graphs G under the restriction $deg(v){\geq}3$ for all vertex $v$ of G. Our result is also an answer of a Klee and Quaife type problem on exponent to find minimum number of vertices of graphs which have fixed even exponent and the degree of whose vertices are always at least 3.

• The Academic Congress of Korean Shoulder and Elbow Society
• /
• 2002.03a
• /
• pp.19-19
• /
• 2002