• Journal of the Korean Society of Safety
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• v.32 no.4
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• pp.16-21
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• 2017

The sprinkler system is a basic fire extinguishing system that uses water as an extinguishing agent. In order to evaluate the fire extinguishing performance of the sprinkler system, information such as the discharge angle, discharge speed, discharge pressure, flow rate, and water droplet size of the installed head are required. However, there is a lack of research on droplets size compared to other requirements. In this study, to evaluate the extinguishing characteristics of sprinkler system, the droplet size distribution was measured for various types of sprinkler heads actually used. The size of the droplet was measured using laser diffraction method. The 50% cumulative volume distribution ($D_{v50}$) according to discharge coefficient(K factor) was $540{\mu}m{\sim}695{\mu}m$ for K50, $542{\mu}m{\sim}1,192{\mu}m$ for K80, $980{\mu}m{\sim}1,223{\mu}m$ for K115 and $1,188{\mu}m{\sim}1,234{\mu}m$ for K202. Based on the measured results, the vaeiance of the droplet particle distribution and the distribution ($D_{v50}$) according to discharge coefficient(K factor) was $540{\mu}m{\sim}695{\mu}m$ for K50, $542{\mu}m{\sim}1,192{\mu}m$ for K80, $980{\mu}m{\sim}1,223{\mu}m$ for K115 and $1,188{\mu}m{\sim}1,234{\mu}m$ for K202. Based on the measured results, the vaeiance of the droplet particle distribution and the Rosin-Rammler index value are presented. As a result of the fire simulation with FDS, it was confirmed that the performance difference occurs according to the water droplet size distribution even when the same amount of water is used. Therefore, the extinguishing performance of the sprinkler system should be evaluated considering the droplet size distribution according to the sprinkler head type.

• Journal of Korean society of Dental Hygiene
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• v.12 no.1
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• pp.81-91
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• 2012

Objectives : By investigating antimicrobial activity of natural extracts, identifying its usefulness as antibiotic material to oral bacteria. Methods : Antimicrobial activity tests of 25 natural extracts were implemented on 6 type strains alleged to cause dental caries and 10 clinical strains isolated and identified from dental caries. Results : Among medicinal plants, Coptis japonica, Scutellaria baicalensis, Dictamnus dasycarpus showed antimicrobial activity. Among lichens, 3 methanol extracts and 6 acetone extracts showed antimicrobial activity. Minimum Inhibitory Concentration(MIC) test of Usnea aurantiacoatra KoLRI 004184, an acetone extract of lichen with the highest antimicrobial activity, on 6 type strains involved in dental caries and 10 strains isolated from dental caries resulted as follows; Actinomyces oris 1041 $12{\mu}g/ml$, for Corynebacterium durum 3151 $13{\mu}g/ml$, for Rothia dentocariosa KCTC $3204^T$ $14{\mu}g/ml$, for R. dentocariosa 911 $15{\mu}g/ml$, for R. dentocariosa 1822 $12{\mu}g/ml$, for Lacto-bacillus casei KACC $12413^T$ $12{\mu}g/ml$, for L. acidophilus KACC $12419^T$ $16{\mu}g/ml$, for L. rhamnosus 2421 $15{\mu}g/ml$, for Streptococcus mutans KCTC $3065^T$ $15{\mu}g/ml$, for S. mutans 121 $13{\mu}g/ml$, for Streptococcus oralis 2221 $18{\mu}g/ml$, for S. salivarius KCTC 5512 $14{\mu}g/ml$, for S. salivarius 122 $12{\mu}g/ml$, for S. sanguinis KCTC $3284^T$ $14{\mu}g/ml$, for S. sanguinis 912 $14{\mu}g/ml$, for Neisseria sp. KEM232 $12{\mu}g/ml$. Conclusions : Even a small amount of extract from lichen Usnea aurantiacoatra KoLRI 004184 showed very high level of antimicrobial activation against all 16 bacterial strains involved in dental caries.

• Journal of Environmental Science International
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• v.11 no.4
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• pp.391-397
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• 2002

This study was carried out with the inhibition of the cholinesterase activity by carbamate insecticides in the chicken in vivo and in vitro. The optimum pH of cholinesterase was 8.0. The cholinesterase activity used the acetylcholin as substrate in plasma was 24.6 $\mu$mol/min/g protein. After oral administration with 0.32 mg/kg of BPMC as carbamate pesticide, the cholinesterase activity was inhibited to 60% of control after 15min in vivo. Then the recovery of cholinesterase activity followed to 97% of control after 12hr. I$_{50}$, such as concentration required for 50% inhibition of enzyme activity, of phenyl N-methylcarbamate were 329 $\mu\textrm{g}$/$\ell$ of XMC, 214 $\mu\textrm{g}$/$\ell$ of metolcarb, 111 $\mu\textrm{g}$/$\ell$ of BPMC, 107 $\mu\textrm{g}$/$\ell$ of propoxur and 104 $\mu\textrm{g}$/$\ell$ of isoprocarb. I$_{50}$ of aromatic N-methylcarbamate were 280 $\mu\textrm{g}$/$\ell$ of carbaryl and 114 $\mu\textrm{g}$/$\ell$ carbofuran.ran.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.1
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• pp.99-105
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• 2000

The purpose of this study was to evaluat the Zn, Cu, Mn and Ni status and correlation of their concentrations in serum, urine, hair and fingernail in female college students. As the results are follows; The mean age of subjects was 22.5 years and height, weight and BMI were 160.1 cm, 51.0 kg and 20.0 respectively. The daily intake of energy 1769.5 kcal and the ratio of carbohydrate, fat and protein for energy is 60 : 20 : 15. The daily intake of energy (88.5%), vitamin B2 (86.1%), Ca (75.4%), Fe (58.3%) and Zn (63.0%) of subjects did not reach to Korean Recommended Dietary Allowance (RDA). The daily mean intake of Zn, Cu, Mn and Ni were 7.56 mg, 2.30 mg, 3.81 mg and 0.18 mg respectively. The concentrations of Zn in serum, urine, hair and nail were 85.6$\mu\textrm{g}$/dL, 391.2$\mu\textrm{g}$/day, 174.6$\mu\textrm{g}$/g and 102.4$\mu\textrm{g}$/g respectively and those Cu were 84.2$\mu\textrm{g}$/dL, 56.6 $\mu\textrm{g}$/day, 20.3$\mu\textrm{g}$/g and 4.3$\mu\textrm{g}$/g respectively. The concentrations of Mn in serum, urine, hari and nail were 0.2$\mu\textrm{g}$/dL, 1.1$\mu\textrm{g}$/day, 1.8$\mu\textrm{g}$/g and 1.6$\mu\textrm{g}$/g respectively and those of Ni were 0.6$\mu\textrm{g}$/dL, 24.5$\mu\textrm{g}$/day, 3.5$\mu\textrm{g}$/g and 3.1$\mu\textrm{g}$/g respectively. The daily intake of Mn showed the positive correlations with concentration of Mn in hair (p<0.05) and the daily intake of Ni was positively correlated with urinary exretion (p<0.05) and hair contents (p<0.001) of Ni. The more detailed studies about these trace mineral status should be required.

• Nuclear Engineering and Technology
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• v.5 no.4
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• pp.279-285
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• 1973

A method for the simultaneous determination of mercury, bromine, arsenic and cadmium in biological samples is described. Following neutron activation and a simple distillation of volatile compounds, mercury and bromine were determined by gamma-ray spectrometry. Arsenic and cadmium were further separated by cation exchange separation and determined similarly. Determination limits for mercury, bromine, arsenic and cadmium were 0.001$\mu\textrm{g}$, 0.003$\mu\textrm{g}$, 0.001$\mu\textrm{g}$ and 0.02$\mu\textrm{g}$, respectively. The method has been applied to the determination of mercury, bromine, arsenic and cadmium in rice and fish samples. Analysis of a standard kale powder yielded the values of 0.046$\mu\textrm{g}$/g for mercury, 24.5$\mu\textrm{g}$/g for bromine 0.17 $\mu\textrm{g}$/g for arsenic and 0.50$\mu\textrm{g}$/g for cadmium.

• The Journal of the Korea institute of electronic communication sciences
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• v.7 no.1
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• pp.125-134
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• 2012

This study examines how the concentration of Fine Particles(PM10: Fine Particles of under Diameter $10{\mu}m$) included in the air influences on the satellite signal transmission frequency band. For the study of satellite signal attenuation rate by the concentration of Fine Particles, the concentration of Fine Particles classified 7 levels, below $50{\mu}g/m^3$, below $100{\mu}g/m^3$, below $200{\mu}g/m^3$, below $400{\mu}g/m^3$, below $800{\mu}g/m^3$, below $1,600{\mu}g/m^3$, below $3,200{\mu}g/m^3$. After then, it analyzed how much each concentration influenced on the satellite signal transmission frequency band.

• Korean Journal of Pharmacognosy
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• v.28 no.4
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• pp.233-238
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• 1997

ln order to search for antigastric cancer agents from Korean traditional prescriptions. We selected 41 traditional prescriptions, based on a review of the Korean traditional medicine books. Both boiling water and methanol extracts were tested, by means of the Sulforhodamine B (SRB) protein assay. Six of the 41 water extracts; #3, #34, #35, #38, #40, #41 showed efficacy against gastric cancer cell (AGS: Human gastric carcinoma, ATCC HTB 103). #3 inhibited 50% cancer cell growth1 at the concentration of $152\;{\mu}g/ml$, #34, #35, #38, #40 and #41 inhibited 50% cancer cell growth at the concentration of $145\;{\mu}g/ml$, $129\;{\mu}g/ml$, $173\;{\mu}g/ml$, $10\;{\mu}g/ml$ and $19\;{\mu}g/ml$ respectively. Ten of the 41 methanol extracts; #1, #3, #32, #33, #35, #36, #37, #38, #41 were active. #1 inhibited 50% cancer cell growth at the concentration of $206\;{\mu}g/ml$, #3, #32, #33, #35, #36, #37, 738, #40, #41 inhibited 50% cancer cell growth at the concentration of $133\;{\mu}g/ml$, $159\;{\mu}g/ml$, $199\;{\mu}g/ml$, $147\;{\mu}g/ml$, $113\;{\mu}g/ml$, $187\;{\mu}g/ml$, $130\;{\mu}g/ml$, $9\;{\mu}g/ml$, $15\;{\mu}g/ml$ respectively. Prescription #3, #35, #38, #40, #41 were also interesting because both methanol and water extracts were active.

• Analytical Science and Technology
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• v.21 no.1
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• pp.53-57
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• 2008

In order to survey the contents of ethyl carbamate in alcoholic beverages, GC/MS-SIM method was used after extraction with dichloromethane in solid phase extract cartridge contained alcoholic beverages. In the applied GC/MS-SIM method, the values of recoveries and relative standard deviation were ranged from 85.2 % to 87.9 % and from 0.7 % to 1.9 %, the limit of detection and quantification were $2{\mu}g/kg$ and $10{\mu}g/kg$. Depending on alcoholic beverage kinds, the levels were variable and the average level was $194{\mu}g/kg$ for liquor, $105{\mu}g/kg$ for fruit wine, $62{\mu}g/kg$ distilled spirit, $28{\mu}g/kg$ for sake, $15{\mu}g/kg$ for yakju, $12{\mu}g/kg$ for other alcohol beverages, ND for soju, respectively.

• Journal of the Korean Society of Marine Environment & Safety
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• v.21 no.1
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• pp.9-17
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• 2015

In order to elucidate the current state of marine pollution of heavy metals around major shipyards in Korea, seawater samples were collected at eleven sampling stations and four control stations around 4 major shipyards located in the southeastern coast of Korea in summer 2010, and 6 kinds of metals such as copper(Cu), zinc(Zn), iron(Fe), cadmium(Cd), lead(Pb) and mercury(Hg) in seawater samples were analyzed. The analyses of heavy metals in seawater showed that the mean Cu concentrations in seawater around 4 major shipyards were in the range of $0.817{\sim}1.638{\mu}g/L$ which were lower than Korean environmental standards of $20{\mu}g/L$ for the protection of human health(PHH) and of $3{\mu}g/L$ for short-term protection of marine ecosystem(SPME) but higher than Cu concentration at control station by a factor of up to 2.75. The mean Zn concentrations were in the range of $0.228{\sim}0.567{\mu}g/L$ which were lower than Korean environmental standards of $100{\mu}g/L$ for PHH and $34{\mu}g/L$ for SPME but higher than Zn concentration at control station by a factor of up to 5.91. The mean Fe concentrations were in the range of $3.332{\sim}7.410{\mu}g/L$ which were higher than Fe concentration at control station by a factor of up to 6.75. The mean Cd concentrations were in the range of $0.013{\sim}0.028{\mu}g/L$ which were lower than Korean environmental standards of $10{\mu}g/L$ for PHH and $19{\mu}g/L$ for SPME but higher than Cd concentration at control station by a factor of up to 2.33. The mean Pb concentrations were in the range of $0.007{\sim}0.126{\mu}g/L$ which were lower than Korean environmental standards of $50{\mu}g/L$ for PHH and $7.6{\mu}g/L$ for SPME. The mean Hg concentrations were in the range of $0.002{\sim}0.004{\mu}g/L$ which were lower than Korean environmental standards of $0.5{\mu}g/L$ for PHH and $1.8{\mu}g/L$ for SPME. Although the concentrations of metals such as Cu, Zn and Fe which were used in shipbuilding works were lower than Korean environmental standards for PHH and SPME, the fact that the concentrations of Cu, Zn and Fe at sampling stations around major shipyards were higher than those at control stations implies that the works in shipyards had some effects on marine water quality around shipyards. Therefore, marine environment management such as the prevention and control of the discharge of various pollutants from shipyards is required on national level.

• THE JOURNAL OF KOREAN ORIENTAL ONCOLOGY
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• v.7 no.1
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• pp.39-60
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• 2001

Fuzhengfangaitang is a prescript for inhibiting recurrence and metastasis of cancer. We had examined the anti-metatstastic effect of Fuzhengfangaitang. Furthermore, we performed the following experiments with ingredients of Fuzhengfangaitang. The purpose of this thesis is to study what ingredients of Fuzhengfangaitang have more valuable anti-cancer effects. And the results are listed below: 1. Cell Viability assay At the dose of 400$\mu$g/ml, most ingredients of Fuzhengfangaitang depressed viability of ECV-304. And especially, Scutellaria barbata D. DON$50{\mu}g/ml$ : 53.118%, $100{\mu}g/ml$: 49.092%, $200{\mu}g/ml$ : 43.765%, $400{\mu}g/ml$ : 12.747%), Polygonum bistorta L.($50{\mu}g/ml$ : 45.554%, $100{\mu}g/ml$ : 45.554%, $200{\mu}g/ml$ : 0.0%, $400{\mu}g/ml$ : 0.0%) and Psoralea corylifolia L.($50{\mu}g/ml$ : 86.591%, $100{\mu}g/ml$ : 81.307%, $200{\mu}g/ml$ : 24.801%, $400{\mu}g/ml$ : 3.111%) highly depressed cell viability more than the other ingredients. (${\alpha}$<0.05) 2. Cell Proliferation assay Proliferation assay with ingredients of Fuzhengfangaitang on ECV-304 showed that Crataegus pinnatifuda BGE ($50{\mu}g/ml$: 63.276%, $100{\mu}g/ml$ : 64.092%, $200{\mu}g/ml$ : 68.966% $400{\mu}g/ml$ : 38.517%, ED50=$296.974{\mu}g/ml$), Polygonum bistorta L.($50{\mu}g/ml$ : 83.981%, $100{\mu}g/ml$ : 86.997%, $200{\mu}g/ml$ : 58.780%, $400{\mu}g/ml$ : 26.408%), ED50=$266.725{\mu}g/ml$) and Psoralea corylifolia L.($50{\mu}g/ml$ : 103.037%, $100{\mu}g/ml$ : 82.529%, $200{\mu}g/ml$ : 2.829%, $400{\mu}g/ml$ : 0.998%), ED50=$177.369{\mu}g/ml$) depressed cell proliferation more than the other ingredients. 3. Tube Formation assay Compared with the control group, most ingredients of Fuzhengfangaitang did not remarkably inhibited the Tube Formation assay of ECV-304 at the dose of $100{\mu}g/ml$. But, Polygonum bistorta L. highly inhibited the tube formation of ECV -304 at the lower dose of $50{\mu}g/ml$. 4. Rat Aortic Ring assay In comparison with the control group, Scutellaria barbata D. DON., root of Polygonum bistorta L. and Psoralea corylifolia L. restricted the angiogenesis of the rat aortic ring at the dose of $100{\mu}g/ml$. And the other ingredients of Fuzhengfangaitang did not restricted the angiogenesis of the rat aortic ring at that dose. Especially, Polygonum bistorta L. highly inhibited the angiogenesis of the rat aortic ring at the lower dose of $50{\mu}g/ml$. From our research, the anti-angiogenic effects of the ingredients of Fuzhengfangaitang was proven. Moreover, it will be helpful for designing more effective prescription for anti angiogenesis.