• Proceedings of KOSOMES biannual meeting
• /
• 2007.11a
• /
• pp.97-102
• /
• 2007

The piggery wastewater is the major source of the water pollution problem in the rural area. The treatment alternatives for piggery wastewater are limited by the characteristics of both high organic and nitrogen(N) content. In order to investigate an efficient N removal system, the thermophilic aerobic digestion process was examined. The experiment was investigated organic and nitrogen removal efficiency at various HRTs and air supply volume. The results of semi-continuous experiment indicated that a higher removal of the soluble portion of COD was achieved with the longer HRTs. However, the inert portion of COD in piggery wastewater was not much changed by thermophilic aerobic digestion. In addition, with the higher HRT of 3 days, up to 79% of NH4-N removal efficiency was achieved. Lower the HRTs, a decrease of NH4-N removal was founds. The gas samples from the lab reactor were analyzed along with the N content in influent and effluent. The N2O formation in our system indicates a novel aerobic deammonification process occurred during the thermophilic aerobic digestion. Both N02 and N03 were not presented in the effluent of thermophilic aerobic digester. With the HRT of 3 days, 36.4% of influent N(or 57.5% removal N) was aerobically converted to N2O gas. The ammonium conversion to N2O gas significantly decrease to 4.5% at low HRT of .05 day..

• Journal of Korean Society for Geospatial Information Science
• /
• v.19 no.4
• /
• pp.23-33
• /
• 2011

In this study, the data that examined the chloride ion concentration of ground water wells in the west coast of Jeollabukdo applying the GIS spatial estimation method were analyzed. In particular, through the designation of a validation point among ground water wells and then the analysis of error characteristics of the chloride ion concentration by each method of IDW (Inverse Distance Weight), Spline, and Kriging Interpolation method which is proper for estimating salt water intrusion was selected. The main conclusion from this study is as follows. First, as a result of analyzing the error characteristics of various spatial estimation methods by using the data from the chloride ion concentration of 485 ground water wells, the IDW method was found to be the most appropriate for estimating chloride ion concentration by salt water intrusion. Second, analyzing the average chloride ion concentration of the targeted regions has revealed that Gunsan-si with the record of $541mg/{\ell}$ did not meet water quality standards even for industrial use. Both Gimje-si and Gochang-gun satisfied drinking water quality standards and Buan-gun with $272mg/{\ell}$ was slightly below the standards for drinking water. Third, concerning the results of analysis according to administrative districts, as the areas adjacent to the west coast such as Daemyeong-dong, Joong-dong, Jangjae-dong and Guemam-dong in Gunsan-si are found to have very high chloride ion concentration, and both Hoehyeon-myeon and Daeya-myeon bounded by the Mankeong river did not meet water quality standards even for industrial use. From these facts, it is concluded that salt water intrusion has a great effect on Gunsan-si generally.

• Journal of Ginseng Research
• /
• v.29 no.3
• /
• pp.138-144
• /
• 2005

This study was to examine antioxidative effects of ginseng extracts on liver of high fat diet-treated mice. ICR male mice were given high fat diet with red ginseng or white ginseng extracts (500, 1500, 3000 mg/kg/day, orally) for 4 weeks. We also Investigated the relationship between lipid peroxidation and ginseng extracts on the oxidative stress. We measured the levels of malondialdehyde (MDA, a marker of lipid peroxidation), hydrogen peroxide, superoxide dismutase (SOD), glutathione peroxidase (GPx) and glutathione (GSH) in liver tissue. The activities of SOD was generally low in all ginseng extract groups. But the activity of GPx was high in all ginseng extract groups. The hydrogen peroxide contents were similar in almost all groups. The level of GSH was higher in all ginseng extract group in high fat diet (FD) group. The levels of MDA (the end product of lipid peroxidation) were lower in all ginseng extract groups than in FD group. These results that the antioxidant effects of red ginseng and white ginseng extracts prevent oxidative damage by antioxidant effects involving SOD, GPx and increasing the ability of the body to synthesize endogenous antioxidants. It was concluded that ginseng can protect against oxidative stress by high fat diet through its antioxidant properties.

• Journal of the Korean earth science society
• /
• v.44 no.1
• /
• pp.36-46
• /
• 2023

In this study, small bird tracks from the Cretaceous Sanbukdong Formation in Gunsan City, South Korea, were briefly described. Detrital zircon SHRIMP U-Pb dating was conducted of the tuffaceous sandstone from the formation to determine the depositional age of the vertebrate track-bearing strata. Small bird tracks are not well-preserved but divided into two types: two consecutive tracks and three isolated tracks. They are small, asymmetric, slender, functionally-tridactyl tracks, which lack a web between digits. The consecutive and isolated tracks were identified as Koreanaornis dodsoni? and Koreanaornis ichnosp., respectively. This study adds avian tracks to the Sanbukdong tetrapod track assemblage composed of theropods, ornithopods, and pterosaur tracks. According to the U-Pb dating, the estimated age of the Sanbukdong Formation is 112.5±5.8 Ma, regard as the Aptian Stage, representing the maximum depositional age for the Sanbukdong Formation. The Sanbukdong Formation can be correlated with the lower part of the Jinju Formation in the Gyeongsang Basin. Thus, small avian tracks may represent the oldest Korean occurrence of Koreanaornis.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• v.2
• /
• pp.169-175
• /
• 2006

기존의 종이지도가 아닌 전자지도(수치지도) 내에 필요로 하는 (속성)정보를 입력하여 체계적으로 구축한 데이터를 이용, 업무의 효율 및 통계적 관리가 가능토록 해주는 GIS의 개념을 이해하고, 이를 응용한 유비쿼터스(Ubiquitous)의 이용분야와 개발현황을 확인함으로써 해상교통안전시설에 활용할 수 있는 방안을 모색해 보고자 함.

• Journal of Magnetics
• /
• v.19 no.4
• /
• pp.323-326
• /
• 2014

Superparamagnetic maghemite nanoparticles were prepared by chemical co-precipitation, followed by a temperate oxidation stage, and investigated using FE-SEM, XRD, TGA, VSM, and M$\ddot{o}$ssbauer spectroscopy. Through SEM image and XRD analysis, its average particle size was found to be 13.9 nm. While VSM magnetic measurement showed typical superparamagnetic behavior at room temperature, M$\ddot{o}$ssbauer spectroscopic investigation revealed that non-vanishing magnetic hyperfine structure were retained. Cation distribution estimated from M$\ddot{o}$ssbauer spectroscopy confirmed the formation of maghemite nanophase in the sample.

• 한국문화재보존과학회:학술대회논문집
• /
• 2006.04a
• /
• pp.157-162
• /
• 2006

• Journal of Magnetics
• /
• v.16 no.4
• /
• pp.368-373
• /
• 2011

Particle size distributions in 10 nm magnetite ferrofluids are analyzed based on both dc and ac magnetic measurements. Modified log-normal distributions are used for fitting the experimental results, which allows for a proper account of the narrow distributions. The calculated average particle sizes are in good agreement with the TEM results. However the ac method gives a much narrower distribution width than that of the dc magnetization curve fit. The proposed measurements combined with the analysis methods are useful for the characterization of ferrofluids being considered for biomedical applications.

• Journal of Species Research
• /
• v.2 no.2
• /
• pp.223-226
• /
• 2013

Pennisetum flaccidum Griseb. (Poaceae) is native to Central Asia. While monitoring Poaceae weeds nationwide in Korea, we found its new naturalized distribution in Gunsan, Jeonrabuk-do. The species is distinguished from P. alopecuroides var. alopecuroides by subsessile involucres and plumose bristles. We provide the first documented record of P. flaccidum Griseb. for Korea with the description and illustration. We also provide a taxonomic key to the species of Pennisetum in Korea.

• Proceedings of KOSOMES biannual meeting
• /
• 2017.11a
• /
• pp.71-71
• /
• 2017