• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.13 no.3
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• pp.308-315
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• 2002

In this paper, the 5-bit digital phase shiftier with 10 InGaAs HEMTs is designed and fabricated for U.S. mobile DBS receiving active phased array antenna system in 12 GHz band. 11.25 $^{\circ}$, 22.5$^{\circ}$ and 45$^{\circ}$ phase bits are designed in leaded-line type. 90$^{\circ}$ and 180$^{\circ}$ phase bits are designed in reflection type combined with ring hybrid. The return loss more than 17.5 ㏈, insertion louts less than 7.8 ㏈, and maximum phase error of $\pm$6$^{\circ}$for 32 phase responses are measured in 12.2 GHz~ 12.7 GHz band.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.22 no.9
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• pp.1208-1216
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• 1998

The present numerical study investigates the effect of a secondary flow on the heat transfer in order to delineate the mechanism of laminar heat transfer enhancement of a viscoelastic fluid in rectangular ducts. The second normal stress generating a secondary flow is modeled by adopting the Reiner-Rivlin constitutive equation and the calculated secondary flow showed good agreement with experiments. The primary velocity U as well as the pressure drop were not affected by the secondary flow in rectangular ducts, whose order of magnitude is less than 0.1% of the primary velocity. The small magnitude of the secondary flow, however, affect moderately the temperature fields. The calculated Nusselt numbers with secondary flow show 50% heat transfer enhancement over those of a purely viscous non-Newtonian fluid, which are considerably lower than the experimental values. Therefore, we conclude that there should be an additional heat transfer enhancement mechanism involved in the viscoelastic fluid such as temperature-dependence.

• Korean Journal of Remote Sensing
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• v.22 no.5
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• pp.427-431
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• 2006

Forest stand height and volume are important indicators for management purpose as well as for the environmental analysis. Shuttle Radar Topography Mission (SRTM) is backscattered over forest canopy and DSM can be acquired from such scattering characteristic, while National Elevation Dataset (NED) provides bare earth elevation data. The difference between SRTM and NED is estimated as tree height, and it is correlated with forest parameters, it is correlated with forest parameters, including average DBH, Trees per acre, net BF per acre, and total Net MBF. Especially, among them, net Board Foot(BF) per acre is the index that well represents forest volume. The Project site was Douglas-fir dominating plantation area in the western Washington an the northern Oregon in the U.S. This study shows a relationship of high correlation between the forest parameters and the product from SRTM, NED, and ETM+. This research performs multi regression analysis and regression tree algorithm, and can get more improved relationship between several parameters.

• The Korean Journal of Food And Nutrition
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• v.22 no.2
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• pp.252-260
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• 2009

According to Article 7 and Annex B of the World Trade Organization(WTO) Agreement on the Application of Sanitary and Phytosanitary(SPS) Measures, WTO members are required to notify their newly established or amended SPS measures that might affect international trade. This study analyzed SPS notifications from 1995 to 2008 to identify international trends for food safety measures. The notifications were collected from the SPS information management system and the official document distribution system of WTO. The 153 WTO members represented 37 developed countries, 84 developing countries and 32 least developed countries. The number of overall notifications was 9,820. The annual notifications increased from 198 in 1995 to 1,264 in 2008. The monthly average notifications were from 44.8 in December to 69.5 in June; however, there were no statistical differences among them. The six leading Members in terms of notification submissions were United States(U.S.), Brazil, New Zealand, Canada, European Community and Korea. Among the regular and emergency notifications, 62.7% notifications were concerned with food safety, followed by animal and plant protections. Among animal protection notifications, 54.8% were emergency situations. Of the 4,821 food safety notifications, 60.4% were from developed countries, and 39.3% were from developing countries. Measures concerning pesticide residues and risk assessments were mainly from developed countries. In contrast, 77.5% of the measures concerning zoonoses were from developing countries. However considering the numbers of developing and developed countries, the average number of measures for each country was similar. Food safety measures were mainly involved pesticide residues followed by food additives, zoonoses, new regulations, labeling. As the overall notifications, zoonosis measures were mainly emergency notifications. Measures concerning pesticide residues, food additives, zoonoses, new regulations, veterinary drugs, and labeling were submitted most often by the U.S., Korea, Albania, U.S., Australia, and U.S., respectively. Identifying the exact trends of food safety measures was complicated by a number of factors. However, WTO notifications might be useful tool in providing a general view of international trends.

• Journal of Radiation Protection and Research
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• v.11 no.1
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• pp.22-28
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• 1986

Densities of a large number of mixed uranyl nitrate-thorium nitrate solutions were measured with pycnometer. By the least squares analysis of the experimental result, an empirical formula for determining water content of mixed uranyl nitrate-thorium nitrate solutions as functions of uranium concentration, thorium concentration and nitric acid normality is derived; $W=1.0-0.358\;C_u-0.4538\;C_{Th}-0.0307\;H^+$ where $W,\;C_u,\;C_{Th},\;and\;H^+$ stand for water content(g/cc), uranium concentration (g/cc), thorium concentration (g/cc), and nitric acid normality, respectively. Water contents of the mixed uranyl nitrate-thorium nitrate solutions are calculated by using the empirical formula, and compared with the values calculated by Bouly's equation in which an additional data, solution density, is required. The two results show good agreements within 2.7%.

• Journal of Veterinary Clinics
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• v.2 no.1
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• pp.105-114
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• 1985

The optimal conditions for the evaluation of serum ornithine carbamyltransferase activity, based on the do-termination of citrulline formed during the enzymatic reaction, were investigated and the serum ornithine carbamyltransferase activity of cattle were surveyed. Barbital-acetate buffer(70m moles/L, pH 7.0 at $37^{\circ}C$) were usea for the entire experiment. The results were as follows. 1. When the concentration of $H_2SO_4$ in color reagent exceeds 3.0 m1/100m1 the serum protein precipitated and absorbance increased. 2. The concentrations of antipyrine and diacetylmonoxime required for maximal color formation were 1g/L and 5g/L, respectively. 3. The absorbance was maximal when the reaction mixture was boiled for 25 minutes. 4. The chromogen were stable for at least 60 minutes under loon lighting condition, but decolorized rapidly under direct sunlight. 5. The minimal concentration of urease solution(Sigma Chemical Co., Type III) required for elimination of serum urea was 0, 6mg/ml. 6. When the concentration of L-ornithine solution increased up to 22m moles/L, the ornithine carbamyltransferase activity was not inhibited by zwitterion of ornithine. 7. In accordance with the increase of carbamylphosphate concentration the ornithine carbamyltransferase activity increased and the nonenzymatic citrulline production also increased slightly. 8. The standard curve of citrulline revealed linear pattern within the range of this experiment (0.1~4.0m moles/L). 9. The ornithine carbamyltransferase activities of normal cattle investigated in this laboratory were 6.85$\pm$4.38U/L (mean$\pm$SD) in cows and 2.89$\pm$2.50U/L in bulls. The range of the activities were 0.39～29.12U/L in cows and 0.06~17.34U/L in bulls.

• Journal of Microbiology and Biotechnology
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• v.7 no.2
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• pp.114-120
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• 1997

Microorganisms producing xylanase were screened for the enzymatic production of xylo-oligo saccharides from xylan. One of the bacteria isolated from compost produced an endoxylanase extracellularly. The bacterium was identified as Bacillus sp. according to its taxonomic characteristics examined. Xylanase production reached upto 5 U/ml after 22 h of culture in LB medium at $30^{\circ}C$. The xylanase was purified by ammonium sulfate precipitation and gel filtration. The molecular weight of the xylanase was estimated to be 20,400 by SDS-PAGE. Optimal temperature and pH for the xylanase activity was $60^{\circ}C$ and 6.5, respectively. The enzyme was stable at temperatures upto $40^{\circ}C$ and pH values from 4 to 10. The xylanase was completely inhibited by the addition of 2 mM mercury ion. Apparent $K_m$ and $V_max$ values for oat spelt xylan were 9.2 mg/ml and 1954 U/mg protein, respectively. For birchwood xylan, the values were 6.3 mg/ml and 1009 U/mg protein. The predominant products of the xylan hydrolysis were xylobiose, xylotriose and xylotetraose, indicating that the enzyme is an endoxylanase. Upto $85{\%}$ of the initially added enzyme (2 U/ml) was bound to 50 mg/ml of the insoluble fraction of oat spelt xylan after incubation at $30^{\circ}C$ for 30 min.

• Korean journal of communication and information
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• v.22
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• pp.211-247
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• 2003

This study explored how Korean immigrants education, length of stay and English fluency affect their political socialization, mediated through traditional news media and the news Web use. Political socialization included political knowledge, interest, and participation. The media usage patterns included U.S. news media, U.S. news Web, Korean news Web, and Korean news Media use by Korean immigrants in the United State. This study found as follows. First, education, length of stay, and English fluency indirectly increased political socialization(political knowledge, interest, and participation) through their relationship with U.S. news media use. Second, U.S. news Web played a potentially important role in Korean immigrants' political socialization by increasing their political interest. Third, Korean news media partly contributed to Korean immigrants' political socialization by increasing their political interest. Fourth, Korean news Web use did not contribute to Korean immigrants' political socialization in terms of political knowledge, interest, and participation at all. In conclusion, this study found that traditional news media's role was more important than news Web's one in the process of immigrants' political socialization to the host society.

• The Journal of Pediatrics of Korean Medicine
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• v.22 no.1
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• pp.13-24
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• 2008

Objectives This study was designed to analyze the clinical studies on Mental retardation(MR) in traditional Chinese medicine(TCM). Methods For this study, we searched the clinical studies on MR, which had been published from 2003 to 2007, through web site CNKI(中國知識基礎設施工 http://www.cnki.net). There were 17 clinical studies and we focused on those studies. Results 1. In those Chinese studies, they used following words to describe Mental retardation; 小人弱智($xi\check{a}o\acute{e}rru\grave{o}zh\grave{i}$), 智能發育不全($zh\grave{i}n\acute{e}ngf\bar{a}y\grave{u}buqu\acute{a}n$), 智力低下($zh\grave{i}l\grave{i}d\bar{i}xi\grave{a}$), 精神發育遲滯($j\bar{i}ngsh\acute{e}f\bar{a}y\grave{u}ch\acute{i}zh\grave{i}$), 智能落后($zh\grave{i}n\acute{e}nglu\grave{o}h\grave{o}u$), 智能落后($zh\grave{i}n\acute{e}ngch\acute{i}hu\check{a}n$), 失天愚型患人($xi\bar{a}nti\bar{a}ny\acute{u}x\acute{i}nghu\grave{a}n'\acute{e}r$). 2. There were many kinds of TCM treatment methods for MR, such as herbal medicine, acupuncture, electroacupunture, acupoint injection, Chuna therapy, and special education. And those TCM treatments methods showed higher efficacies in the treatment of MR compared with Western medicine. 3. Mental retardation was related with the deficiency of heart, kidney, liver, spleen(心虛, 腎虛, 肝虛, 脾虛) and the pathological mechanism of Phlegm(絹) and Blood stasis(慫沂)in the studies about the Bian Zheng-the types of differential diagnosis- of MR. 4. Most of studies used Intelligence Quotient(IQ) to assess the efficacy of TCM treatment of MR. And the duration of treatment, the degree of illness, the age of patient, and the cause of illness affected the prognosis of MR. Conclusions These results suggest that traditional medicine could be one of the useful treatments on MR. And these results could be used in the clinical practices and studies on MR in Korea.

• Journal of the Korean Applied Science and Technology
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• v.40 no.6
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• pp.1330-1339
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• 2023

In order to verify whether the serum using the medicinal plant Coptis japonica is effective in anti-aging of the skin, the improvement rate was analyzed by measuring the skin elasticity and radiance of the subjects, and the satisfaction was evaluated through a questionnaire. Twenty-two female subjects were given a serum containing 3% Coptis Japonica extract on one cheek for 4 weeks, and the test site was measured, and the skin elasticity increased by 5.73% from 0.8505 ± 0.0395 R2 (mm) before use to 0.8993 ± 0.0234 R2 (mm) after 4 weeks. Skin glow increased by 4.74% from 55.94 ± 5.49 (a.u.) to 58.59 ± 4.66 (a.u.), and the probability of significance was p<0.001, indicating a significant increase in the improvement rate of both items. It was found that all subjects were 100% satisfied with the improvement of elasticity and 95.5% satisfied with the improvement of radiance, and no skin abnormalities were found during the trial period. These results are expected to be used as basic data for future research and product development of anti-aging functional cosmetics using Coptis Japonica extract.