• The Transactions of the Korean Institute of Electrical Engineers C
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• v.50 no.12
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• pp.599-606
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• 2001

In this paper, the ac breakdown characteristics of pure Ar, Kr and $N_2$ gas with gas pressure range of 58.8-137.3[kPa] under uniform and non-uniform fields were investigated, and the measured values were compared with those In Ar/$N_2$ and Kr/$N_2$ gas mixtures with pressure varying. Summarizing the experimental results, the breakdown voltages of Pure $N_2$gas, under uniform and non-uniform fields, were increased about 4.8 and 1.1 times than those of pure Ar gas, and about 4.4 and 1.2 times than those of pure Kr gas, and the ac breakdown voltage increased with the pressure increasing. The breakdown voltages of Ar/$N_2$ gas mixtures were decreased with decreasing the mixture ratio of Pure $N_2$ gas. In case of Ar(85%)/$N_2$ (15%) and Ar(70%)/$N_2$ (30%) gas mixtures comparing to the pure Ar gas, the breakdown voltages under uniform field were increased about 1.8 and 2.2 times, and under non-uniform field were increased about 1.1 and 1.3 times at the pressure of 101.3[kPa]. Also, in case of Kr(85%)/$N_2$ (15%) and Kr(70%)/$N_2$ (30%) gas mixtures comparing to the pure Kr gas, the breakdown voltages under uniform field were increased about 1.7 and 2.0 times, and under non-uniform field were increased about 1.0 and 1.2 times. Corona inception voltage of Kr(70%)/$N_2$(30%) gas mixtures under non-uniform fields were increased about 1.28 times than those of Ar(70%)/$N_2$ (30%) gas mixtures. In case of practical incandescent lamps, luminous and lifetime of Kr(70%)/$N_2$ (30%) gas mixtures were increased about 1.15 and 1.21 times than those of Ar(70%)/$N_2$ (30%) gas mixtures.

• Reproductive and Developmental Biology
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• v.37 no.4
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• pp.269-279
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• 2013

Low efficiency of somatic cell nuclear transfer (SCNT) is attributed to incomplete reprogramming of transfered nuclei into oocytes. Trichostatin A (TSA), histone deacetylase inhibitor and 5-aza-2'deoxycytidine (5-aza-dC), DNA methylation inhibitor has been used to enhance nuclear reprogramming following SCNT. However, it was not known molecular mechanism by which TSA and 5-aza-dC improve preimplantation embryo and fetal development following SCNT. The present study investigates embryo viability and gene expression of cloned porcine preimplantation embryos in the presence and absence of TSA and 5-aza-dC as compared to embryos produced by parthenogenetic activation. Our results indicated that TSA treatment significantly improved development. However 5-aza-dC did not improve development. Presence of TSA and 5-aza-dC significantly improved total cell number, and also decreased the apoptotic and autophagic index. Three apoptotic-related genes, Bak, Bcl-xL, and Caspase 3 (Casp3), and three autophagic-related genes, ATG6, ATG8, and lysosomal-associated membrane protein 2 (LAMP2), were measured by real time RT-PCR. TSA and 5-aza-dC treatment resulted in high expression of anti-apoptotic gene Bcl-xL and low pro-apoptotic gene Bak expression compared to untreated NT embryos or parthenotes. Furthermore, LC3 protein expression was lower in NT-TSA and NT-5-aza-dC embryos than those of NT and parthenotes. In addition, TSA and 5-aza-dC treated embryos displayed a global acetylated histone H3 at lysine 9 and methylated DNA H3 at lysine 9 profile similar to the parthenogenetic blastocysts. Finally, we determined that several DNA methyltransferase genes Dnmt1, Dnmt3a and Dnmt3b. NT blastocysts showed higher levels Dnmt1 than those of the TSA and 5-aza-dC blastocysts. Dnmt3a is lower in 5-aza-dC than NT, NTTSA and parthenotes. However, Dnmt3b is higher in 5-aza-dC than NT and NTTSA. These results suggest that TSA and 5-aza-dC positively regulates nuclear reprogramming which result in modulation of apoptosis and autophagy related gene expression and then reduce apoptosis and autophagy. In addition, TSA and 5-aza-dC affects the acetylated and methylated status of the H3K9.

• The Korean Journal of Pesticide Science
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• v.7 no.3
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• pp.169-175
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• 2003

For safe and easy disposal of prochloraz wastewaters after used as rice seed disinfectant in Korean farms, this experiment was carried out. By addition of several agricultural materials commonly utilizing in farmers, removal effect of prochloraz from waste solution was also investigated. When rice seeds after soaking in diluted prochloraz solution were rinsed with water several times, prochloraz was removed $9.2\sim10.6%$ at the first rinse and less than 3 % at the fourth rinse. A half life of prochloraz was $4\sim5$ days in aqueous system. Hydrolysis of prochloraz was more rapidly in alkali solution than neutral and acidic one at $25^{\circ}C$ and $35^{\circ}C$. By the irradiation under $5530J/cm^2$ using xenone lamp, prochloraz was photo-degraded to 87.7% in aqueous system. The removal efficiency of prochloraz by addition of several agricultural materials were as follows: 93.6% by lime, 90.7% by composed pig manure, 89.4% by activated charcoal, 78.0% by straw ash, 70.3% by sandy loam soil, 47.0% by zeolite and 24.1 % by rice straw. When prochloraz solution was sprayed on the field soil, it was dissipated upto 90% within 35 days.

• Transactions of the Korean Society of Automotive Engineers
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• v.13 no.4
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• pp.74-80
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• 2005

This paper presents a misfire monitoring method by using the weight factor. According to OBD II(On-Board Diagnostics) regulations of the CARB (California Air Resources Board), an ECU (Electronic Control Unit) should detect misfires which occur in the internal combustion engine. A misfire is 1311owe4 by post-oscillations for short duration. Sometimes, the amplitude of oscillations may be as high as misfire and can be falsely detected as another misfire. To prevent this, the software designers do not attempt to detect another misfire for this short duration, during which the post oscillations exist. Because of this, ECU does not detect all the misfires and hence, the unstable state of automobile cannot be detected. If this happens for a long time, automobile may get damaged. To solve these problems, this paper suggests a new algorithm to detect misfire by using weighting factor Weighting factor is a concept to distinguish the misfire with the post oscillation and to improve the detection rate. This value of weighting factor is used for counting the misfire. This paper also shows the result of experiment done on a automobile using this software. The software is implemented using ASCET-SD which is preferred in the design of engine control. This paper's result show the possibility of improving the misfire detection by implementing this algorithm.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.6
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• pp.644-653
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• 2002

Sizes of coastal squid jogging boats, their light source output for fishing lamps and daily catch data were collected, for a purpose of evaluating factors on fishing boats, which affect to the squid catch, from four fishing ports (Hakodate, Sado Island, Noto and Tsushima) in Japan. The catch amount was increased as boat sizes and their light source output of fishing lamps were increased up to 100$\~$200 kW class and 11$\~$15 gross tonnage class. The relationship between catch per unit efforts y (box/machine/day), gross tonnage x_{1}, (GT) and light source output for fishing lamps x_2 (kW) is expressed as following formula; $y=4.091+0.18x_1+0.0019x_2$. Thus, 0.1819 boxes of squid catch can be expected, when light source output for fishing lamps increases for 1 kW $(x_2{\leq}200)$ and boat size 1 GT ($x_1\leq15$). It is considered that the boat size which created a shadow area under the jigging boat, is important factor affecting to catch amount, Because larger shadow area created by bigger boat has a possibility to let more squid stay there.

• Strategy21
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• s.37
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• pp.5-31
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• 2015

The Republic of Korean Navy (ROKN) started from scratch. However, ROKN demonstrated its Blue Navy capabilities successfully to the entire world by conducting "Operation Early Dawn" at the Aden Bay, Yemen in Jan 2011. On the event of the 70th anniversary of the ROKN, I would like to retrospect past gleaning from voyages and challenges we had in the past. At the very inception of the ROKN, Korean government as well as senior military leaders recognized that it had no time to spare to clean up military those were insinuated deeply by communist agents. It was the top priority of the government. The Mongumpo Operation which was not well known, conducted by ROKN was one of the clean-up drive. The Korean War sometimes called as "a fire from land put-off at the sea". The world famous "Incheon Landing" which reversed war situation from the Nakdong Perimeter also done by Sea Power. ROKN conducted various maritime operations including not only Incheon Landing, but amphibious operation at Hungnam, mine sweeping, sea convoy, Wonsan Withdrawal. On the same day of the Korean War started, 25th June 1950, unless the victory of the ROKNS Baekdusan (PC 701) at the Korean Strait, the waning lamp light of Korea could not be rekindled by the participation of the U.N. The ROKN rescued the 17th regiment of Korean Army from the isolation at the Ongjin Peninsular and transported gold and silver bars stored at the Bank of Korea to the Navy supply deposit in Jinhae safely. ROKN special intelligence unit conducted critical HUMINT which led Incheon Landing success. One of important mission ROKN conducted successfully was not only transporting war fighting materials but also U.S. provided grains to starving Koreans. ROKN participated Vietnam campaign from 1960s and conducted numerous maritime transportation operations supplying materials to Vietnam military forces along the long coastal lines. Experienced Naval Officers and enlisted men who discharged and acquired as merchant marine certificate supported most of the U.S. sea lift operations throughout the Vietnam campaign. ROK-US Combined Forces which had been honed and improved its war fighting capabilities through the Korean War and out of Vietnam jungle playing key deterrent against threat from north Korea. However, those threat level will be completely different when north Korea finish its nuclear weapon ambition. In order to stand firm against north Korean nuclear threat, I would like to expect strong political leadership supporting nuclear submarine for ROKN.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.8
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• pp.1795-1801
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• 2009

In this study, a portable flashlight which can manually generate the electricity by using sunlight was developed so that it can be used in the extreme environmental condition such as no-electricity condition. Battery is charged by using solar battery during the day, but when sunlight is not avalible during the night or rainy day, a handle is rotated to generate the electricity in order to charge the battery manually. To improve the brightness of the light, light is concentrated by using the optical lens. Low electric consumption circuit is used for the longer operating time by suppress electrical consumption while lamp is discharged. A circuit is designed and used for steady electrical curris dand voltage to insure steady battery charging. Super-discharge circuit and protection circuit are used for the super discharge of battery when it is not used for a long time. Also the constant charge is possible by using houseware adapter. As a result, a portable flashlight is designed to charge with sunlight during day, and with houseware adapter during night. A portable flashlight is also designed to irradiate longer distances by improvement of the brightness of the light using the optical lens. Thus, it forms white natural ray of light making possible for night reading.

• Journal of Veterinary Clinics
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• v.25 no.6
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• pp.482-487
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• 2008

This study was performed to investigate the ophthalmic findings of the Korean traditional 'Sapsaree' dogs, and to provide ophthalmic references. Five hundred forty-seven Sapsaree dogs were randomly chosen without any criteria preference. Ophthalmic examination was performed bilaterally using ocular equipments, including slit-lamp biomicroscope, tonometer, direct and indirect ophthalmoscope. The obtained data for ophthalmic findings were analysis by the multivariate linear regression model to identify effects of sex, age and hair coat type. For congenital conditions, the incidence of persistent pupillary membrane (PPM) was the most common defect and there was present 8.8 % whereas for acquired ophthalmic diseases, cataract was the most commonly observed (3.7 %) in Sapsaree dog. Other frequent ocular finding included persistent hyaloid vessel remnant (PHVR, 6.2 %) in congenital conditions, and postinflammatory retinal degeneration (PIRD, 3.1 %) and corneal dystrophy (2.4 %) in acquired ophthalmic diseases. Only one significant effect was age of the Sapsaree for PIRD (P=0.040). There are no any significant effect for sex and hair coat types. This study will provide useful guidelines to clinicians and breeders for the basic ophthalmic information on this breed.

• Korean Journal of Food Science and Technology
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• v.48 no.5
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• pp.525-529
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• 2016

Twenty-nine pepper products commercially available in the market were collected and investigate for contamination levels. Pepper products purchased from traditional markets had a degree of contamination of $10^6-10^7CFU/g$ aerobic bacteria, $10^4-10^5CFU/g$ Bacillus sp., and less than $10^2CFU/g$ yeast and molds. Organic pepper showed a degree of contamination of $10^4$ aerobic bacteria, $10^2-10^3$ Bacillus sp., and less than $10^1$ yeast and molds. Intense pulsed light (IPL) treatment of 10 min (1,000 V, 5 pps and 4 cm sample-to-lamp distance) showed a bacterial death rate of 1.45-1.55 log for whole peppers, and of 0.8-0.85 log for black and white pepper powder. The sterilization rate using IPL was higher than that using other non-thermal sterilization methods, such as ozone treatment or low-pressure discharge plasma sterilization, indicating that the IPL sterilization method may find potential application in the industry. However, further studies may need to be conducted to enhance the effect of sterilization.

• Korean Journal of Food Science and Technology
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• v.34 no.4
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• pp.631-636
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• 2002

Lethality of high intensity light pulse on the pre-determined microbial populations has been investigated. Prior to the treatment, Lactobacillus plantarum, Lactobacillus brevis, Leuconostoc mesenteroides and Pediococcus pentosaceus were cultivated separately onto the surface of Lactobacilli MRS agar. Pre-determined microbial populations were applied to the test media and these sample were exposed to high intense light source with an exposure time ranging from 1 to $2500\;{\mu}s$. Results showed that at least 200 light pulses of $1\;{\mu}s$ duration were required to reduce L. Plantarum cells by 90% at 25 kV, the greater the number of light pulses, the larger the reduction in viable cell numbers. Viable cells of L. plantarum and the others were reduced by more than 5 and 6 log cycles at the upper exposure level of $750\;{\mu}s$, respectively. These study shows that pulsed light emissions can significantly reduce populations of lactic acid bacteria on exposed surface with exposure times. Killing efficiency for L. plantarum significantly increased with decreasing the distance between the lamp and the surface of samples.