• Korean Journal of Food Science and Technology
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• v.35 no.5
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• pp.937-942
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• 2003

Kimchi was prepared with 5, 10 or 20%(w/v) Chinese radish and ripened at $20^{\circ}C$ for 3 days. Acid production and growth of lactic acid bacteria, sensory properties, and several volatile odor components in kimchi were examined. The effects of freeze-drying on the quality of kimchi were also studied. The pH of the control (kimchi prepared without Chinese radish) was 4.31 and gradually decreased as the amount of Chinese radish increased. The acidity of the control was 0.673% and gradually increased as the amount of Chinese radish increased. Viable counts of lactic acid bacteria in the samples did not differ significantly from the control. The pH of freeze-dried/rehydrated kimchi slightly decreased as the amount of Chinese radish increased while its acidity gradually increased. The viable count of lactic acid bacteria of freeze-dried/rehydrated kimchi did not differ significantly as the amount of Chinese radish increased. Overall acceptability and taste of kimchi and freeze-dried/rehydrated kimchi generally improved by the addition of 10% or 20% Chinese radish. Six volatile odor components including ethanol and five sulfur-containing components (SCC) were identified from unripened kimchi, and the level of two SCCs increased as the amount of Chinese radish increased. Eight volatile odor components, ethanol and seven SCCs, were identified from ripened kimchi and the level of five SCCs increased as the amount of Chinese radish increased. Diallyl sulfide and methyl trisulfide were newly detected from the ripened samples, but not from the unripened kimchi. Freeze-drying substantially reduced all of the volatile odor components from kimchi. Five volatile odor components including ethanol and four SCCs were identified from the freeze-dried/dehydrated samples.

• The Journal of Korean Medicine
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• v.18 no.1
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• pp.357-374
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• 1997

In order to investigate the effects of Sakunjatang(四君子湯) and Samultang(四物湯) aqua-acupuncture on immune response, Sprague-Dawley male rats were used and randomly divided into four group. Normal group was normal control, Control group was injected i.v. with 2mg/kg MTX on 9th and 11th day after sensitization with SRBC on 5th day, Sakunjatang aqua-acupunctured group(Sample A) was aqua-acupunctured daily for 18 days into the locus corresponding Bisu(B20) locus of the human body to Rat and MTX was administered 9th and 11th experimental day, Samultang aqua-acupunctured group(Sample B) was aqua-acupunctured daily for 18 days into the locus coresponding Bisu(B20) locus of the human body to Rat and MTX was administered 9th and 11th experimental day. In the 9th day and the 11th day after aqua-acupuncture, MTX was injected to reduce immune function in the tail of rat. leukocyte count, lymphocyte ratio, lymphocyte count of spleen, lymphocyte count of bonemarrow, contact hypersensitivity to DNFB, morphologic change of thymus cell, and electropherogram of serum protein. The result were summarized as follows: 1. Before MTX injection, leukocyte count had no significant difference in Sakunjatang aqua-acupunctured group and Samultang aqua-acupunctured group compared to control group and after MTX injection, leukocyte count had no significant difference Sakunjatang aqua-acupunctured group and Samultang aqua-acupunctured group. 2. Before MTX injection, lymphocyte ratio was decreased significantly Sakunjatang aqua-acupunctured group and Samultang aqua-acupunctured group compared to control group. 3. After MTX injection, lymphocyte ratio was increased significantly Sakunjatang aqua-acupunctured group, Samultang aqua-acupunctured group had no significant difference compared to control group. 4. The lymphocyte count of spleen was increased significantly Sakunjatang aqua-acupunctured group and Samultang aqua-acupunctured group compared to control group. 5. The lymphocyte count of bonemarrow was increased significantly Sakunjatang aqua-acupunctured group, Samultang aqua-acupunctured group had no significant difference compared to control group. 6. Contact hypersensitivity was no significant difference in Sakunjatang aqua-acupunctured group and Samultang aqua-acupunctured group compared to control group. 7. In the morphologic change of thymus cell, control group compared to normal group had a indistinct boundary between cortex and medulla, and lymphocyte cell density of thymus was low, Sakunjatang aqua-acupuryctured group had a distinct boundary between cortex and medulla, and lymphocyte cell density of thymus was high. 8. In the SDS-PAGE electrophorogram of serum protein, Sakunjatang aqua-acupunctured group and Samultang aqua-acupunctured group had a wide band of nearby 50,000 and 25,000 Dalton which meant IgG generate more activity.

• Nuclear Engineering and Technology
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• v.45 no.5
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• pp.605-612
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• 2013

Removal of decay heat from an operating reactor during a prolonged station blackout condition is a big concern for reactor designers, especially after the recent Fukushima accident. In the case of a prolonged station blackout condition, heat removal is possible only by passive means since no pumps or active systems are available. Keeping this in mind, the AHWR has been designed with many passive safety features. One of them is a passive means of removing decay heat with the help of Isolation Condensers (ICs) which are submerged in a big water pool called the Gravity Driven Water Pool (GDWP). The ICs have many tubes in which the steam, generated by the reactor core due to the decay heat, flows and condenses by rejecting the heat into the water pool. After condensation, the condensate falls back into the steam drum of the reactor. The GDWP tank holds a large amount of water, about 8000 $m^3$, which is located at a higher elevation than the steam drum of the reactor in order to promote natural circulation. Due to the recent Fukushima type accidents, it has been a concern to understand and evaluate the capability of the ICs to remove decay heat for a prolonged period without escalating fuel sheath temperature. In view of this, an analysis has been performed for decay heat removal characteristics over several days of an AHWR by ICs. The computer code RELAP5/MOD3.2 was used for this purpose. Results indicate that the ICs can remove the decay heat for more than 10 days without causing any bulk boiling in the GDWP. After that, decay heat can be removed for more than 40 days by boiling off the pool inventory. The pressure inside the containment does not exceed the design pressure even after 10 days by condensation of steam generated from the GDWP on the walls of containment and on the Passive Containment Cooling System (PCCS) tubes. If venting is carried out after this period, the decay heat can be removed for more than 50 days without exceeding the design limits.

• Journal of Life Science
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• v.24 no.8
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• pp.880-886
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• 2014

In this study, we isolate and identify bacteria from seawater collected from Jeju coast, to evaluate the antimicrobial activity against the fish pathogenic bacteria. 14 bacterial strains were isolated and identified using physiological, biochemical and molecular tools. Antibacterial activity of all the 14 isolates were screened against four major fish pathogens namely, two Gram-positive: Streptococcus iniae, Streptococcus parauberis and two Gram-negative: Vibrio anguillarum, Edwardsiella tarda. Results revealed that among the 14 isolates, MK-11 was found to have antibacterial activity against S. iniae, S. parauberis, V. anguillarum Particularly, S. iniae was susceptibility with the MIC value of $250{\mu}g/ml$. The biochemical and physio-chemical results reveal that MK-11 had the sugar-alcohol disassemble ability of the D-sorbitol and D-mannitol. Also the utilization of the yeast extract, sorbitol and di-potassium phosphate were noted to be high. The optimum culture condition such as pH and temperature was recorded as pH 6.0, $25^{\circ}C$ and along with 1% NaCl which differs from the previous reports particularly in nutrient resolutions. As results of the analysis of 16S rDNA sequences, MK-11 show the high similarity with Paenibacillus polymyxa, P. jamilae, P. brasilensis 99.78%, 99.43%, 99.39%, repectively. Hence, in the present study, the isolated Paemibacillus sp. MK-11 from Jeju seawater possesses the antibacterial activity against fish pathogens and it could be used as a new antibiotic agents against the gram positive fish pathogens.

• Korean Journal of Applied Biomechanics
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• v.17 no.1
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• pp.91-97
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• 2007

The purpose of this study was to investigate the changes of various balls velocity under the different surface conditions after impact. For this study, four different balls were used which are golf ball, tang-tang ball, table tennis ball, and iron ball. And two different types of ground conditions were used which are artificial grass green and glass green. Movements of putter head and ball were recorded with 2 HD video cameras(60 Hz, 1/500s shutter speed). Small size control object($18.5cm{\times}18.5cm{\times}78.5cm$) was used in this study. To transfer the same amount of kinetic energy to the ball, pendulum putting machine was used. Analyzing the process of impact and the ball movement, a putter was digitized the whole movement but the ball was digizited within the 50cm movement. Velocities were calculated by the first central difference method(Hamill & Knutzen, 1995). Putter head velocities were about 112.2cm/s-116.2cm/s at impact. Maximum ball velocities were appeared 0.08s-0.10s after impact no matter what the ground conditions are. Table tennis ball recorded higher ball velocities than the other ball velocities and iron ball recorded the lowest ball velocity in this group. But Table tennis ball was influenced with the frictional force and immediately was decreased at the artificial grass green condition. If an object is received the kinetic energy under the static condition(v=0cm/s), the object recorded the maximum velocity shortly after the impact and then decreased the velocity because of the frictional force. The ball distance from the start position to the peak velocity position is about 6cm-10cm under the 112.2cm/s-116.2cm/s putting velocity with putter. 0.25 seconds later after impact balls were placed 40cm distance from the original position except iron ball. In this study, ball moving distances were too short therefore it was not possible to investigate the reactions after the translational force is disappeared. Rotational force would play a major role at the end of the ball movement. Future study must accept two things. One is long distance movement of ball and the other is balanced ground. Three-piece ball is a good item to investigate the golf ball movement on the different surface conditions.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2001.06a
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• pp.8-8
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• 2001

초고속 증착은 짧은 시간에 박막 형성을 가능하게 하므로 window glass 코팅등의 대면적 코팅에 있어서 비용을 절감 시키고, 대량생산을 가능하게 만들기 때문에 관심이 집중되고 있다. 고속증착 공정으로는 high current arc, laser arc, hollow cathode discharge ion plating 그리고 마그네트론 스퍼터링법 등이 있다. 특별히 마그네트론 스퍼터링법은 3m이상의 넓이에 코팅을 할때 두께가 매우 균일하며, 증착율은 evaporation 공정에 비해 경제적, 기능적인 면에서 효율적이다. 그리고 증착된 박막은 매우 조밀하고 좋은 밀착력을 갖고 있으며, 고융점 금속을 포함하여 금속 합금 및 혼합물의 비율을 조정 및 금속 산화물, 질화물, 탄화물 등과 같은 금속의 증착도 stoichiometry를 조정하여 박막을 합성 시키는데 있어서 효과적이다. 이러한 초고속 증착을 만들기 위한 마그네트론 스퍼터링법의 요건은 마그네트론 원이 높은 타켓 power density를 가져야 하며, 타켓에서 효율적으로 플라즈마를 구속하여 스퍼터 되는 이온의 양을 최대화 시킬 수 있어 한다. 따라서 본 실험에서는 초고속 증착을 위해서 직경 50mm 타켓의 UBM magnetron원을 설계 제작하였다. 고밀도의 플라즈마를 형성시키기 위해서, Poisson simulation c code를 이용하여 자기장의 방향, 세기 및 밀도를 측정 하였고, 자기장 측정기(Gauss meter)를 이용하여 실제 자장을 측정 비교 분석하였다. 상기의 data를 바탕으로 여러 형상의 마그네트론원을 설계, 제작하였고. 마그네트론 원의 특성 분석을 위해 I-V 방전 특성을 평가하였고 substrate ion current density와 박막의 증착율을 측정하였다.duty-on 시간의 증가에 따라 $Cr_2N$ 상의 형성이 점점 많아져 80% duty-on 시간 경우에는 거의 CrN과 $Cr_2N$ 상이 공존하는 것으로 나타났다. 또한 duty-on 시간이 증가할수록 회절피크의 세기가 증가하여 결정화가 더 많이 진행되어짐을 알 수 있었다. 마찬가지로 바이어스 펄스이 주파수에 다른 결정성의 변화도 펄스의 주파수가 증가할수록 박막이 결정성이 좋아지고 $Cr_2N$ 상이 쉽게 형성되었다. 증착 진공도에 따른 결정성은 상대적으로 질소의 농도가 높은 낮은 진공도에서는 CrN 상이 주로 형성되었으며, 반대로 높은 진공도에서는 $Cr_2N$ 상이 많이 만들어졌다. 즉 $1.3{\times}10^{-2}Torr$의 증착 진공도에서는 CrN 상만이 보이는 반면 $9.0{\tiems}1-^{-2}Torr$ 진공도에서부터 $Cr_2N$ 상이 형성되기 시작하여 $5.0{\tiems}10^{-2}Torr$ 진공도에서는 두개의 상이 혼재되어 있음을 알 수 있었다. 박막의 내마모성을 조사한 결과 CrN 박막의 마찰 계수는 초기에 급격하게 증가한 후 0.5에서 0.6 사이의 값으로 큰 변화를 보이지 않았으며, $Cr_2N$ 박막도 비슷한 거동을 보였다.차 이, 목적의 차이, 그리고 환경의 의미의 차이에 따라 경관의 미학적 평가가 달라진 것으로 나타났다.corner$적 의도에 의한 경관구성의 일면을 확인할수 있지만 엄밀히 생각하여 보면 이러한 예의 경우도 최락의 총체적인 외형은 마찬가지로 $\ulcorner$순응$\lrcorner$

• Journal of Surface Science and Engineering
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• v.40 no.6
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• pp.254-257
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• 2007

TiN coating on tool steel has been widely used for the improvement of durability of tools. In this work, radical nitriding(RN) is carried out on SKD61 at $450^{\circ}C$ for 5 hours in the ammonia gas pressure $2.7{\times}10^3\;Pa$. The TiN coating is carried out by arc ion plating(AIP) with the process parameters: arc power 150 A, bias voltage -50V, coating time 40 minutes and nitrogen gas pressure $4{\times}10^3\;Pa$. Hardness, elastic modulus, friction coefficient and adhesion of TiN coating on substrates of both TiN/SKD61 and TiN/RN SKD61 coatings are investigated comparatively. The primary crystalline faces of TiN surface are(200) and(111) for TiN/SKD61 and TiN/RN SKD61 respectively. In addition to the primary phase, Fe phase exists in TiN/SKD61 coating, but not in TIN/RN SKD61. The hardness of TiN/RN SKD61 is about 700 Hv, 250 Hv(56%) higher than that of TiN/SKD61 at the near interface of TiN and substrates. At the TiN surface, hardness of TiN/RN SKD61 is 2,149 Hv, 71 Hv(3%) higher than that of TiN/SKD61. The elastic modulus of TiN coating is improved to 26.7 GPa(6%) by radical nitriding. The adhesion is improved by the RN coating showing no spalling. buckling and chipping on the scratch test track which are shown on the non-RN TiN/SKD61.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.45 no.1
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• pp.50-55
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• 2008

In this paper, New LC VCO with $8{\sim}10.9$ GHz Band has been designed using commercial $0.35-{\mu}m$ CMOS technology. This proposed circuit is consisted of the parallel construction of the typical NMOS and PMOS cross-coupled pair which is based on the LC tank, MOS cross-coupled pair which has same tail current of complementary NMOS and PMOS, and output buffer. The designed LC VCO, which is according to proposed structure in this paper, takes a 29% improvement of the wide tuning range as 8 GHz to 10.9 GHz, and a 6.48mW of low power dissipation. Its core size is $270{\mu}m{\times}340{\mu}m$ and its phase noise is as -117dBc Hz and -137dBc Hz at 1-MHz and 10-MHz offset, respectively. FOM of the new proposed LC VCO gets -189dBc/Hz at a 1-MHz offset from a 10GHz center frequency. This design is very useful for the 10Gb/s clock generator and data recovery integrated circuit(IC) and SONET communication applications.

• BMB Reports
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• v.37 no.4
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• pp.454-459
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• 2004

Experimental hyperoxia represents a suitable in vitro model to study some pathogenic mechanisms related to oxidative stress. Moreover, it allows the investigation of the molecular pathophysiology underlying oxygen therapy and toxicity. In this study, a modified experimental set up was adopted to accomplish a model of moderate hyperoxia (50% $O_2$, 96 h culture) to induce oxidative stress in the human leukemia cell line, U-937. Spectrophotometric measurements of mitochondrial respiratory enzyme activities, NMR spectroscopy of culture media, determination of antioxidant enzyme activities, and cell proliferation and differentiation assays were performed. The data showed that moderate hyperoxia in this myeloid cell line causes: i) intriguing alterations in the mitochondrial activities at the levels of succinate dehydrogenase and succinate-cytochrome c reductase; ii) induction of metabolic compensatory adaptations, with significant shift to glycolysis; iii) induction of different antioxidant enzyme activities; iv) significant cell growth inhibition and v) no significant apoptosis. This work will permit better characterization the mitochondrial damage induced by hyperoxia. In particular, the data showed a large increase in the succinate cytochrome c reductase activity, which could be a fundamental pathogenic mechanism at the basis of oxygen toxicity.

• Journal of Sasang Constitutional Medicine
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• v.8 no.2
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• pp.239-255
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• 1996

The study was conducted for the purpose of finding out an objective classification method for the Sasang Constitutional medicine, which divides people into 4 groups of constitution and presents comprehensively physiology, pathology, diagnosis, theraphy and recuperation fit to each constitution. Questionnaire of Sasang Constitution collected during 9 months from March 1995 to November 1995. For the purposes of this study, the collected data were analyzed by crosstabs, variation analysis, discrimination analysis. The analyzing program was SPSS PC+V4.0. The results were as follows : 1. QSCC consists of the authorized questions studied by te oriental medicine specialists based on "four groups" given the diagnosis of Sasang Constitution Classification and variation analysis by scores of body constitution. 2. When human's body constitution is classified on the basis of QSCC scores of body constitutions and classified by the absolute size, group cases correctly classified was So-Yang-In 17.3%, Tae-Em-In 26.4%, So-Em-In 74.2%, Tae-Yang-In 100%. However, the number of examples are rare. Average percent of "group" cases correctly classified was 39.3%. 3. When human's body constitution is classified on the basis of QSCC scores of body constitutions and clasified by the relative size, group cases correctly classified was So-Yang-In 40.5%, Tae-Em-In 29.1%, So-Em-In 49.2%, Tae-Yang-In 100%. However, the number of examples are rare. Average percent of "group" cases correctly classified was 39.6%. 4. If the diagnosis of body constitution applies to the people after discrimination formula applies to them before the scores of body constitution is correctly analyzed, group cases correctly classified was So-Yang-in 50.5%, Tae-Em-In 36.9%, So-Em-In 55.9%, Tae-Yang-In 100%. However, the number of examples are rare. Average percent of "group" cases correctly classified was 44.03%. 5. As discrimination formula is applied and analyzed based on the questions of higher percent of reaction freqency, So-Yang-in 61.4%, Tae-Em-In 48.8%, So-Em-In 62.0%. Average percent of group cases correctly classified was 54.91% and it was percent increased compared to chance probability. 6. Therefore, it comes to the conclusion if we utilize QSCC, we are able to predict Sasang Constitution.