• The Journal of Asian Finance, Economics and Business
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• v.7 no.11
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• pp.23-31
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• 2020

This paper investigates the impact of monetary policy independence shock on bond yield by allowing for heterogeneous coefficients in the model based on panel data for 19 developing countries using quarterly data from 1991 to 2016. First, we estimate the model using conventional panel VAR estimation with the assumption of homogeneous coefficients across countries. Second, by performing Chow and Roy-Zellner tests to check the homogeneity assumption, we find that the assumption does not hold in the model. Third, we apply a mean-group estimation for panel VAR as a solution for heterogeneity panel model. The results reveal that central bank independence is effective in reducing bond yield with the maximum at period 6 after the shock. Shock one standard deviation bond yield has a negative effect on consumption and investment. We determine that central bank independence has a contradictory effect on real activity; a negative effect on consumption but a positive influence on investment for the first two years after the shock. Additionally, we split our sample into three groups to make the subgroups pool. Our empirical result shows that monetary policy independence shock reduces bond yield. Meanwhile, the response of economic activity to bond yield varies for all three groups.

• Journal of the Korean Society of Food Science and Nutrition
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• v.15 no.3
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• pp.306-312
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• 1986

Demonstration of the highly positive correlation between blood cholestrol levels and heart disease has made consumers wary of the fats in meat, milk and eggs. The egg, as perhaps the single largest common source of cholesterol, has been cited by many members of the medical and scientific world as a food contributing to heart disease. In light of decreasing per capita egg consumption and continuing dietary egg cholesterol controversy, many researchers have focused their efforts on egg nutrition. The results reported, however, are often contradictory. In spite of the disputable scientific evidence, the egg has been labelled (erroneously) as a highly cholesterogenic food. The objective of this presentation is to present a general picture of the problem and discuss our laboratory findings relevant to the problem. An isotope technique was utilized to incorporate $^{14}C$-cholesterol into egg yolk lipoproteins and study the metabolic fate of dietary ovo-cholesterol in rats. Two hundred and fifty micro-curies of 4-$^{14}C$-cholesterol, emulsified in corn oil, were orally administered to five Single Comb White Leghorn laying hens. Eggs were collected, hard-boiled, and the hot dried egg yolk powder (HEY) was prepared. Total radioactivity excreted via feces was determined. The rat groups fed egg yolk powder excreted more than 95% of the ingested ovo-cholesterol, whereas the rat chow group excreted only 47%. No difference was observed between HEY and CEY treatments. Therefore, an unknown lipid factor present in egg folk accelerates cholesterol turnover rate and excretion via feces.

• Publications of The Korean Astronomical Society
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• v.30 no.2
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• pp.371-374
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• 2015

Classical Cepheids (hereafter Cepheids) belong to a class of important variable stars that can be used to determine distances to nearby galaxies via the famous period-luminosity (PL) relations, i.e. the Leavitt Law. In turn, these distances can then be used to calibrate a host of secondary distance indicators located well within the Hubble flow, and ultimately determine the Hubble constant in a manner independent of the Cosmic Microwave Background (CMB) measurements. Some recent progress in determining the Hubble constant to within ~ 3% level via the Cepheid-based distance scale ladder (the SH0ES and the Carnegie Hubble Program) were first summarized in this Proceeding, followed by a brief discussion on the prospect of using ultra-long period Cepheids (ULPC) in future distance scale work. ULPC are those Cepheids with periods longer than 80 days, which seem to follow a different PL relation than their shorter period Cepheids. It has been suggested that ULPC can be used to determine the Hubble constant in "one-step". However, based on the two ULPCs found in M31, it was found that the large dispersion in derived distance moduli leads to a less accurate distance modulus to M31 compared to the classical Cepheids. This finding might raise an alert regarding the use of ULPCs in future distance scale work.

• Nuclear Engineering and Technology
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• v.40 no.2
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• pp.139-146
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• 2008

This paper presents two of the fuel channel designs being considered for the CANDU-SCWR, a pressure-tube type supercritical water cooled reactor. The first is an insulated pressure tube design. The pressure tube is thermally insulated from the hot coolant by a porous ceramic insulator. Each pressure tube is in direct contact with the moderator, which operates at an average temperature of about $80^{\circ}C$. The low temperature allows zirconium alloys to be used. A perforated metal liner protects the insulator from being damaged by the fuel bundles and erosion by the coolant. The coolant pressure is transmitted through the perforated metal liner and insulator and applied directly to the pressure tube. The second is a re-entrant design. The fuel channel consists of two concentric tubes, and a calandria tube that separates them from the moderator. The coolant enters between the annulus of the two concentric fuel channel tubes, then exits the fuel channel through the inner tube, where the fuel bundles reside. The outer tube bears the coolant pressure and its temperature will be the same as the coolant inlet temperature, ${\sim}350^{\circ}C$. Advantages and disadvantages of these designs and the material requirements are discussed.

• Journal of Microbiology
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• v.45 no.3
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• pp.193-198
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• 2007

A marine bacterium was isolated from Mai Po Nature Reserve of Hong Kong and identified as Vibrio cholerae MP-1. It contains a small plasmid designated as pVC of 3.8 kb. Four open reading frames (ORFs) are identified on the plasmid, but none of them shows homology to any known protein. Database search indicated that a 440 bp fragment is 96% identical to a fragment found in a small plasmid of another V. cholerae. Further experiments demonstrated that a 2.3 kb EcoRI fragment containing the complete ORF1, partial ORF4 and their intergenic region could self-replicate. Additional analyses revealed that sequence upstream of ORF1 showed the features characteristic of theta type replicons. Protein encoded by ORF1 has two characteristic motifs existed in most replication initiator proteins (Rep): the leucine zipper (LZ) motif located at the N-terminal region and the alpha helix-turn-alpha helix motif (HTH) located at the C-terminal end. The results suggest that pVC replicates via the theta type mechanism and is likely a novel type of theta replicon.

• International Journal of Contents
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• v.9 no.2
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• pp.27-37
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• 2013

From the perspective of the domestic capital markets, there have been few researches on the financial characteristics of the firms belonging to the KOSDAQ(Korea Securities Dealers Automated Quotation) market, in comparison with those of the firms in the KOSPI. This study has performed three hypothesis tests to obtain the following results: By employing the 'panel data' analysis, it was found that, for the book-value based leverage, all of the six proposed IDVs were statistically significant as the financial determinants of leverage, across the two proxies measuring profitability (i.e., PFT and ROE), while all of the IDVs except VOLATILITY, also seemed to be the attributes to explain the market based dependent variable in the model with the PFT. Moreover, there may be statistically significant (structural) changes (or quasi-experiment) ) between the pre- and post-U.S. financial crisis in the year of 2008, when measured the leverage with the market-value basis with utilizing the Chow F-test. Finally, based upon the logistic regression results, the probability for a firm to be classified into the Prime section in the KOSDAQ market, may be higher, as its profit margin and asset turnover increase.

• The Korean Journal of Food And Nutrition
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• v.20 no.3
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• pp.259-264
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• 2007

Ginger(Zingiber officinale Roscoe) has been used as a raw material in many various traditional preparations since the ancient times. As a component of traditional health products, ginger is known to be effective as an appetite enhancer, and has anti-cold and anti-inflammatory activities. This study was performed to investigate the immunomodulative effects of Zingiber officinale Roscoe in mice, using ex vivo experiments. In order to elucidate ginger's immunomodulative effects of Ginger, water extracts were orally administered to mice, and isolated macrophages were used as the experimental model. To identify the ex vivo effects, six to seven week old Balb/c mice were fed a chow diet ad libitum and the ginger water extracts were administered orally every other day for two or four weeks at two different concentrations(50 and 500 mg/kg b.w.). The results show that IL-IO and $IFN-{\gamma}$ were detected in the 500 mg/kg b.w. supplemented group with LPS stimulation in all cases. Also, the $IFN-{\gamma}$ /IL-10 ratio ranged from 3~5 with mitogen stimulation such as Con A and LPS. In conclusion, this study suggests that ginger extracts may enhance the immune function by regulating the cytokine(IL-10 and $IFN-{\gamma}$) production capacity of activated macrophages in mice.

• Journal of Nutrition and Health
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• v.30 no.7
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• pp.803-812
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• 1997

The influences of dietary supplements of vitamin E on hepatocellular chemical carcinogenesis have been studied, Placental glutathione S-transferase(GST-P) positive foci area, antioxidant enzymes(superoxide dismutase(SOD), catalase, glutathione reductase, glutathione peroxidase, glutathione S-transferase(GST)), glucose 6-phosphatase(G6Pase) activities, and lipid peroxidation of mecrosomes(thiobarbituric acid reactive substances(TBARS) contents) were investigated. For is purpose , we used the murine chemical hepatocardinogenic procedure induced by modified Ito model, which consists of 200mg/kg body weight diethylinitrosamine (DEN) injection, 0.01% 2-acethlaminoflurene(2-AAF) feeding for 6 weeks, and partial hepatectomy on week 3. Weanling Sprague-Dawley male rats were fed pulverized Purina rat chow with 15, 000IU/kg diet vitamin E from initiation or promotion stages. We found that vitamin E supplement decreased the area of GST-P positive foci. Catalase, glutathione peroxidase, glutathione reductase. GST activities, and TBARS contents were decreased. On the other hand G6Pase activities were increased by vitamin E supplement. It seemed that vitamin E supplements helped endogenous defense systems against carcinogenesis by decreasing TBARS contents, $H_2O$$_2$ and organic peroxides. So, vitamin E seemed to protect cell from free radical damage in carcinogenesis. Anticarcinogenic effects of vitamin E were more effective at intiation that at promotion stage. These results suggest that vitamin E has suppressive effects on hepatocellular chemical carcinogenesis, probably through antioxidant effects against TBARS contents $H_2O$$_2$ and orgainc peroxides.

• Proceedings of the Korea Water Resources Association Conference
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• 2019.05a
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• pp.321-321
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• 2019

수공구조물을 설계하는데 설계강우량을 결정하기 위한 강우시간분포의 생산은 중요한 요소이고 주로 Huff 방법, Mononobe 방법, SCS 방법, Yen and Chow 방법 등을 이용하고 있다. 그러나 Huff 방법 등들로 한국의 극치강우사상을 고려하기에는 반영하지 못하는 한계점이 있었다. 본 연구에서는 기존 방법들의 한계점을 극복하고 한국 극치강우사상의 집중지속시간 특성을 반영하는 HSD 방법을 제시하여 서울과 대구광역시에 적용해 설계빈도에 관한 강우 시간분포를 발생시키고 설계 강우량을 산정하며 기존 기법들과 비교하였다. 이에 따라 연구결과를 통해 Huff 방법과 HSD 방법의 첨두 강우량은 지속시간이 길어질수록 차이가 상당하였고 과거 극치강우사상을 살펴보면 HSD 방법을 반드시 고려할 필요가 있다고 판단되었다. 게다가 기후변화로 인해 집중호우현상이 더욱 심해져서 Huff 방법만 이용할 경우 추후에 큰 문제가 발생할 수도 있다. 그래서 수공 구조물 설계 시 HSD 방법을 이용한 대상 지역의 집중지속시간 특성을 반영하는 설계 강우량과 Huff 방법을 이용한 설계 강우량을 같이 고려하여 비교 선택하면 안전한 수공구조물 설계를 실시 할 수 있을 것으로 판단되었다.

• Proceedings of the Korea Water Resources Association Conference
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• 2018.05a
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• pp.436-436
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• 2018

하천의 조도계수는 하상 입자들의 크기 및 형상, 식생, 수로의 만곡 등 흐름특성에 영향을 주는 복합적인 경험적 매개변수이므로 그 값을 정확히 산정하는 것은 매우 어렵다(Chow, 1959). 제주도 산지하천은 하상이 매우 불규칙하고 조도계수의 불확실성으로 인해 정확한 홍수위, 홍수량 산정이 어렵다. 또한 하상경사가 매우 급하여 상류와 사류가 복합적으로 발생하므로 수치모의 시 수위차가 크게 발생할 우려가 있다. 따라서 현장실측 기반의 하천 조도계수 산정을 통한 홍수위, 홍수량 산정에 정확도를 향상시킬 필요가 있다. 이 연구에서는 제주도 북부지역의 건천(한천, 병문천, 독사천, 산지천)을 대상으로 하상재료를 직접 실측하여 하상 입경을 이용한 조도계수를 산정하였다. 실측 방법은 대상하천의 현장답사 및 현장조사를 사전에 실시하였으며, 하천의 종단 방향으로 1km 간격, 100개 이상의 하상재료를 표본으로 취하고 선격자법을 적용하였다. 대상하천 하류부의 좌안, 우안은 대부분 하천 정비에 의한 제방 구축이 되었으며, 상류부는 경사가 급한 암질로 구성되어 있으므로 하상을 중심으로 구성물질의 입경과 조고를 측정하여 상류 흐름의 영향범위를 고려한 조도계수를 산정하였다. 표본 측정시 점 사주, 여울, 웅덩이 등 국부적으로 하상재료의 변화가 심한 구역은 피하고 가급적 해당 구역에서 보편적으로 산재된 하상재료를 선택하였다. 향후 부정류 모형인 HEC-RAS를 이용하여 실측 유량과 수위를 적용한 조도계수를 산정한다면 보다 정밀한 조도계수를 산정할 것으로 판단된다.