• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.spc1
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• pp.259-263
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• 2006

A direct HPLC method was used to analyze determination of resveratrol in grapes and wines. Content of resveratrol in different parts of 13 grape cultivars and 13 wines were quantified. The average total resveratrol content was $143.5{\mu}g/g$. Resveratrol contents in the skin, fruit, seed and fruit stem were distributed range of $0.9{\sim}104.8{\mu}g/g,\;0.1{\sim}0.5{\mu}g/g\;1.7{\sim}173.9{\mu}g/g\;2.9{\sim}247.4{\mu}g/g$, respectively. Resveratrol contents in 13 wines were distributed range of $253.3{\sim}11,271.6{\mu}g/g$.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.44 no.1
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• pp.79-84
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• 2007

In this paper, a fully-integrated low phase noise multi-band CMOS VCO using automatic level controller (ALC) and switched LC tank has been presented. The proposed VCO has been fabricated in a 0.13-um CMOS process. The switched LC tank has been designed with a pair of capacitors and two pairs of inductors switched using MOS switch. By using this structure, four band (2.986 ${\sim}$ 3.161, 3.488 ${\sim}$ 3.763, 4.736 ${\sim}$ 5.093, and 5.35 ${\sim}$ 5.887 GHz) operation is achieved in a single VCO. The VCO with 1.2 V power supply has phase noise of -118.105 dBc/Hz @ 1 MHz at 2.986 GHz and -113.777 dBc/Hz @ 1 MHz at 5.887 GHz, respectively. The reduced phase noise has been approximately -1 ${\sim}$ -3 dBc/Hz @ 1 MHz in the broadest tuning range, 2.986 ${\sim}$ 5.887 GHz. The VCO has consumed 4.2 ${\sim}$ 5.4 mW in the entire frequency band.

• Applied Chemistry for Engineering
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• v.24 no.4
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• pp.382-390
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• 2013

Foaming process of waste soda lime glasses by just chemical composition control of vitreous feed materials was investigated to find a novel and efficient recycling process. For the chemical composition control of feed materials, 10 wt. parts of $SiO_2$, 0.5 wt. parts of $Na_2SO_4$, 3.0 wt. parts of $B_2O_3$, and 0.3 wt. parts of carbon black as the foaming agent were mixed with 100 wt. parts of soda-lime vitreous feed powder. Proper conditions for foaming process in tunnel kiln are the foaming temperature of $830{\sim}850^{\circ}C$, the foaming time of 30~35 min, and the vitreous feed powder particle size of -325 mesh. Properties of foamed glass blocks obtained under these foaming conditions showed the density of $0.17{\sim}0.21g/cm^3$, thermal conductivity of $0.06{\pm}0.005kcal/h{\cdot}m{\cdot}^{\circ}C$, moisture absorption of 1.1~1.5%, and compressive strength of $20{\sim}30kgf/mm^2$.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.41 no.1
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• pp.35-45
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• 2005

The experiment was conducted to investigate the species composition of catches collected by the bottom trawl on June 24 to 26, 2004 in the southern waters of Korea using a trawler "DONGBAEK" belongs to Yosu National University. The investigation was carried out at the 5 stations and the towing speed was 3.4${\sim}$3.7k't. The catches were composed of 46 species from 37 families, 10 orders and 2 classes for fishes and 2 species, 2 families and 2 orders for Chondrichthyes and 44 species, 35 familes, 8 orders for Osteichthyes. The catches of Perciforms were the highest as 24 species and 18 families for fishes. The catches of Spear squid, Loli해 bleekeri and Red banded lobster, Metanephrops thomsoni were also the highest for mollusca and crustacea as 1 class, 3 species, 3 families, 2 orders, 1 class and 7 species, 5 families, 1 order, 1 class respectively. In the 5 stations, number of individuals and biomass were 1,144 and 376.0kg at ST-1, 908 and 240.3kg at ST-2, 666 and 90.1kg at ST-3, 2,050 and 300..4kg at ST-4 and 561 and 24.7kg at ST-5. The diversity index of each stations ranged between 1.49 and it showed the richness index of 2.13${\sim}$3.48, the evenness index of 0.48${\sim}$0.77 and the dominance index of 0.43${\sim}$0.8. Body length distributio of the dominant specise were 9${\sim}$32cm(fork length) for Japanese horse mackerel, Trachurus japonicus, 7${\sim}$23cm(mantle length) for Common squid, Todarodes pacificus, 9${\sim}$43cm(mantle length) for Spear squid, Loli해 bleekeri, 23${\sim}$36cm(total length) for File fish, Thamnaconus modestus, 10${\sim}$28cm(fork length) for Yellow porgy, Dentex tumifrons, 10${\sim}$36cm(fork length) for Target dory, Zeus faber and 8${\sim}$35cm(fork length) for Red seabream, Pagrus major.

• Korean Journal of Ecology and Environment
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• v.44 no.1
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• pp.9-21
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• 2011

This study is conducted to know the change in water environment of Lake Hwajinpo from 2000 to 2008 with physico-chemical parameters; salinity, dissolved oxygen, total phosphorus and total nitrogen and others. And zooplanktons and phytoplanktons were studied from 2007 to 2008. From the water quality data of Lake Hwajinpo from 2000 to 200S; water temperature, salinity, transparency, chemical oxygen demand and dissolved oxygen ranges are $2.8{\sim}29.4^{\circ}C$, 0.23~33.2‰, $0.2{\sim}1.8\;m$, $0.2{\sim}20.2\;mg\;L^{-1}$ and $0.1{\sim}17.4\;mg\;L^{-1}$ and the average values are $18.0^{\circ}C$, 15.7‰, 0.7 m, $5.7\;mg\;L^{-1}$ and $8.0\;mg\;L^{-1}$, respectively. Total phosphorus (TP) and total nitrogen (TN) ranges are $0.024{\sim}0.869\;mg\;L^{-1}$ (average 0.091) and $0.240{\sim}5.310\;mg\;L^{-1}$ (average 1.235). Average TN/TP ratio is 16.4. The annual variations in COD, TP, TN and Chl.${\alpha}$ are compared. COD in 2000 is $4.83\;mg\;L^{-1}$ and 2008 is $1.80\;mg\;L^{-1}$ which is reduced by $0.34\;mg\;L^{-1}$ every year. TP in 2000 is $0.07\;mg\;L^{-1}$ and 2008 is $0.05\;mg\;L^{-1}$ reduced gradually. Yearly reduction in TN is $0.09\;mg\;L^{-1}$, in 2000 and 2008 the values are $1.54\;mg\;L^{-1}$ and $0.77\;mg\;L^{-1}$ respectivly. Chl.${\alpha}$ in 2000 is $46.30\;{\mu}g\;L^{-1}$ and $5.78\;{\mu}g\;L^{-1}$ in 2008; yearly reduction is $4.50\;{\mu}g\;L^{-1}$. The tropic state index (TSI) in south and north parts of Lake Hwajinpo in 2000 are 67 and 63 which are reduced to 63 and 59 in 2008 respectively. North and south part of Lake Hwajinpo have 67 species of phytoplankton under 47 families in 2007 and 2008. Dominant species in south part in 2007 are; Asterococcus superbus in May, Lyngbya sp. in September and Trachelomonas spp. in November and in 2008 Anabaena spiroides in August are abundant and varies with time. Zooplankton species in Lake Hwajinpo are 25 of 25 families. Dominant species in south part in May and August 2007 and May and November in 2008 Copepoda larvae and in September 2007 Protozoa spp. of Protozoan and Brachionus plicatilis and Brachionus urceolaris of Cladocera in August 2008. Dominant species in north part Asplanchna sp. of Cladecera in August and November 2007 and rest of the time are larvae of Copepoda. In this way, the water quality of Lake Hwajinpo is changing with slow rate in the long period specially nutrients concentration (TP, TN etc) is decreasing.

• Journal of Preventive Medicine and Public Health
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• v.29 no.3 s.54
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• pp.669-678
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• 1996

Helicobacter pylori is now recognized as causative agent of chronic gastritis and peptic ulcer, and strongly associated with development of gastric carcinoma. With development of sensitive and specific serologic tests to identify individuals infected with Helicobacter pylori, the epidemiologic study of this diseases has been investigated. But it's transmission route is not established, yet. The purpose of this study is to measure the prevalence of Helicobacter pylori infection in healthy children and young adults and to evaluate related factors for Helicobacter pylori infection in Korea. The seroprevalence of Ig G antibodies to Helicobacter pylori was determined using a Enzyme Linked Immunosorbent Assay and we obtained the information, such as demographic characteristics, monthly household income, numbers of family members in the house, numbers of persons using same room, type of house, and type of drinking water through the questionnaire survey. The observed overall seropositivity rate was 25.7%. The rate is increased progressively from 5.8% in the age group $1\sim3$ years to 44.4% in the age group $20\sim29$years($\chi^2$ for trend, p<0.001). Especially, the rate increased steeply from 6.5% in the age group $4\sim6$ years to 20.8% in the age group $7\sim9$ years, and this suggested that elementary school age was the major acquisition time of Helicobacter pylori infection. In multivariate logistic regression model, age, numbers of family members in the house, and type of house was statistically significant variables for Helicobacter pylori infection. Each odds ratio(93% CI) were as follows; base to age group $1\sim9$ years, age group $10\sim19$ years $3.6(2.0\sim6.4)$, age group $20\sim29$ years $7.3(4.1\sim13.1)$ and base to group of $1\sim3$ family members, group of $4\sim5$ family members $2.1(1.1\sim4.0)$, group of 6 or more family members $2.7(1.3\sim5.4)$ and base to apartment, single and multihouse $1.9(1.1\sim3.5)$. Sex, monthly household income, numbers of persons using same room, and type of drinking water was not statistically significant for Helicobacter pylori infection.

• Analytical Science and Technology
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• v.15 no.2
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• pp.172-179
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• 2002

Determination were performed for the presence of three common environmental endocrine disrupting compounds (EDC), namely nonylphenol (NP), octylphenol (OP), di(2-ethylhexyl)phthalate (DEHP) in rainwater, distilled water, millipore water, groundwater, tap water, and bottle water in market, using OASIS cartrige extraction and GC/MS-SIM. Octylphenol was not detected in any water samples. The order of nonylphenol concentrations were increased in rainwater < millipore water < distilled water < groundwater < tap water < bottle water. The concentration of nonylphenol in bolltle water was $0.44{\mu}g/L$(ppb) at highest. Di(2-ethylhexyl)phthalates were detected in every water samples, and the concentrations were to be $1.70{\sim}2.92{\mu}g/L$ in rainwater, $8.7{\sim}31.7{\mu}g/L$ in distilled water, $0.6{\sim}5.6{\mu}g/L$(mean: $2.5{\pm}0.3{\mu}g/L$) in millipore water, and that were very stable values than other waters, $1.1{\sim}6.0{\mu}g/L$ in groundwater at near Jeonju, $3.1{\sim}5.8{\mu}g/L$ by means in tap water, $0.5{\sim}67.6{\mu}g/L$ in bottle water from market. The concentration of DEHP in bottle water samples from market were in higher than USEPA regulation at over 40%.

• Journal of radiological science and technology
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• v.30 no.3
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• pp.245-250
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• 2007

This research measured the shielding rates of apron 0.25 and 0.5 mmPb for X-ray energy in diagnosis radiation system and gamma-ray energy of $^{99m}Tc$-MDP and $^{18}F$-FDG. X-ray energies were measured on effective energy of $26.2{\sim}45.6\;keV$ when additional filtering plate of 0, 2 mmAl is used within the range of tube voltage $40{\sim}120\;kVp$, and at this time, apron 0.5 mmPb has shown about 5.5% of increase in its shielding rate over 0.25 mmPb at the highest quality. Besides, the aprons of the two types have shown high shielding rate of over 90% for direct X-ray and spatial dose rate. And, in case 0.25 and 0.5 mmPb aprons were used at 140keV of $^{99m}Tc$-MDP, the shielding effects were between 30 and 53%, and at high energy of 511 keV, $^{18}F$-FDG, the shielding effects of apron, $1.3{\sim}3.6%$, were very small.

• Clean Technology
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• v.25 no.3
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• pp.223-230
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• 2019

This research was performed to evaluate the characteristics of food waste from 5 areas in Gangwon Province, Korea and to predict the $CH_4$ gas production rate. Food wastes were sampled in July and September, 2017. The amount of methane gas generation was evaluated through the biochemical methane potential (BMP) test and a calculation method using chemical composition. Average bulk density and pH of the food wastes were in the range of $0.758{\sim}0.850g\;cm^{-3}$ and 4.29 ~ 4.75, respectively. By physical composition, vegetables were the highest with 56.43 ~ 72.81% with fruits recording 5.31 ~ 8.95%, cereals 1.60 ~ 18.73%, fish and meat 4.47 ~ 12.11%, and filtrate 1.76 ~ 3.64%. The average water content was 69.30 ~ 75.87%, and VS and ash content were 22.50 ~ 27.98% and 1.63 ~ 2.48%, respectively. In addition, $BOD_5$, $COD_{Cr}$, and $COD_{Mn}$ were in the ranges of $17,690.3{\sim}33,154.9mg\;L^{-1}$, $106,212.3{\sim}128,695.5mg\;L^{-1}$, and $51,266.1{\sim}63,426.3mg\;L^{-1}$, respectively. The NaCl content ranged from 0.81 to 1.17%. The results of elemental analysis showed that the contents of C, H, O, N, and S were 44.87 ~ 48.1%, 7.12 ~ 7.57%, 40.13 ~ 43.78%, 3.22 ~ 4.14%, and 0.00 ~ 0.02%, respectively. In a comparison of the methane production yield per VS mass of food waste, there was no significant difference between the cumulative amount (${0.303{\sim}0.354m_{CH4}}^3\;{kg_{VS}}^{-1}$) by the BMP test and the theoretical amount (${0.294{\sim}0.352m_{CH4}}^3\;{kg_{VS}}^{-1}$) calculated by chemical composition.

• Korean Journal of Food Science and Technology
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• v.24 no.5
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• pp.482-491
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• 1992

Experiments were conducted to elucidate the effects of pH change and sodium alginate, gum karaya and gum arabic on the foaming properties of soy protein isolate (SPI). The surface tensions of SPI solution (5%) adding to gums at pH 4.0 and 5.0, near the isoelectric point (pH 4.5) were higher than those at pH 7.0 and 8.0. Specific viscosity of the solutions adding to gums (0.1, 0.2 and 0.3%) at pH 7.0 and 8.0 were $3.6{\sim}51.8$ and $4.0{\sim}51.2$, respectively. In cases of addition of sodium alginates specific viscosity were predominantly increased, while those of gum arabic did not almost increase. Addition of gums reduced the overrun, but it stabilized the foams, especially those of sodium alginates (0.2%) increased the foam stability at pH 5.0, 7.0 and 8.0 by 57, 413 and 315%, respectively. Foaming ability, foam stability and heat stability of the foam were significantly (p<0.05) affected by changing pH. There was a tendency to increase the foaming ability according to the decrease of surface tension. Specific viscosity was also important in foam stability and heat stability.