• The Journal of Engineering Geology
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• v.26 no.3
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• pp.413-422
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• 2016

With the rapidly increasing population density and development of infrastructure, the loss of life and property damage caused by landslides has increased gradually in urban area. Especially, Because Busan has high percentage of mountainous terrain among the metropolitan in Korea, it is unavoidable to develop mountainous region excessively. The objective of this evaluation is to study on landslide hazard possibility for Mt. Hwangryeong in Busan Metropolitan City using the infinite slope model considering the groundwater level. All data related to creating the thematic maps was carried out using ArcGIS 10.0. The results show that FS (Factor of Safety) for landslide is inversely proportional to groundwater level change as expected. Most area indicates stable state in dry condition, and unstable area increase due to high pore water pressure when the groundwater level rise. However, several places in high lineament density area where landslide has been previously occurred, are more stable than other places according to the analysis. This inconsistency between real situation and analysis results indicates that additional analytical method would be necessary to solve the problem. Therefore, we suggest that development of new infiltration theory for unsaturated zone would be helpful to evaluate groundwater level distribution as time goes by.

• Applied Microscopy
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• v.35 no.4
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• pp.24-31
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• 2005

The preservative condition and ultrastructure on the mummified hair collected from newly found female mummy in Paju, were investigated by using scanning and transmission electron microscopes. The female mummy was found in september, 2002 during the traditional reburial process for the buried ones. The hair of 16th century mummy showed very intact appearances during observation with electron microscope. And the structures of the cortex, medulla and cuticle were well preserved. The cuticle layer was easily discernable, which are composed of six to seven cuticular cells. Each cuticular cells surrounded and thus seperated from its neighbors by intercellular membrane complex. In the cortex, many macrofibrils and some melanin granules between them were observed. We observed well preserved rod form macrofibrils running parallel along the direction of hair shaft. Especially, melanin granules were aggregated in the cortex which was adjacent to the cuticlu layer. As to the cause for the well-preservation of 440 year old hair sample, the presence of surface coat on the hair, which are composed of various materials. As calcium was included in the surface coat in Electron Dispersive X-ray Spectroscopy (EDS), the hardening process of the surface coat by calcium might inhibit the water or microorganism infiltration into the hair.

• Korean Journal of Soil Science and Fertilizer
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• v.39 no.2
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• pp.109-115
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• 2006

Understanding characteristics of claypan soils has long been an issue for researchers and farmers because the high-clay subsoil has a pronounced effect on grain crop productivity. The claypan restricts water infiltration and storage within the crop root zone, but these effects are not uniform within fields. Conventional techniques of identifying claypan soil characteristics require manual probing and analysis which can be quite expensive; an expense most farmers are unwilling to pay. On the other hand, farmers would be very interested if this information could be obtained with easy-to-use field sensors. Two examples of sensors that show promise for helping in claypan soil characterization are soil profile strength sensing and bulk soil apparent electrical conductivity (ECa). Little has been reported on claypan soils relating the combined information from these two sensors with grain crop yield. The objective of this research was to identify the relationships of sensed profile soil strength and soil EC with nine years of crop yield (maize and soybean) from a claypan soil field in central Missouri. A multiple-probe (five probes on 19-cm spacing) cone penetrometer was used to measure soil strength and an electromagnetic induction sensor was used to measure soil EC at 55 grid site locations within a 4-ha research field. Crop yields were obtained using a combine equipped with a yield monitoring system. Soil strength at the 15 to 45 cm soil depth were significantly correlated to crop yield and ECa. Estimated crop yields from apparent electrical conductivity and soil strength were validated with an independent data set. Using measurements from these two sensors, standard error rates for estimating yield ranged from 9 to 16%. In conclusion, these results showed that the sensed profile soil strength and soil EC could be used as a measure of the soil productivity for grain crop production.

• Journal of Wetlands Research
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• v.19 no.1
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• pp.80-89
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• 2017

Researches about NPS(Non-point Pollution Source) reduction have been widely carried out in recent years. A pilot channel-type constructed wetland (wet swale) was constructed in Rongyin area to treat stormwater generated from a green house agro-land of 22.7 ha. From 2006 to 2008, monitoring was conducted to evaluate its performance on the removal effect for organic pollutants as well as nutrients. Totally, sampling trips of 17 rainfall events were made and they covered most types of storm events in Korea. The channel-type constructed wetland have average removal efficiencies of 78.3~92.0%, 56.4~66.1%, 28.2~45.5% and 50.6~66.4% for SS, COD, TN and TP, respectively. According to four methods for estimating the removal efficiency, the average efficiencies of TSS, COD, TN and TP are 86.0%, 60.1%, 30.1% and 53.5%, respectively. From 2006 to 2008, annual efficiency improved due to infiltration potential increase. It was found that most of the pollutants removed in this channel type of wetland was particulate solids bound pollutants, which is assumed fact that it lacks of physico-chemical treatment conditions which are commonly observed in the retention type of constructed wetlands.

• Journal of Physiology & Pathology in Korean Medicine
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• v.24 no.2
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• pp.290-295
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• 2010

Gamigunggui-tang (GMGGT) is one of the important prescriptions that has been used in oriental medicine. We investigated the inhibitory effect of an oral administration of hot water extract of GMGGT on the development of atopic dermatitis (AD) by using Balb/c mice. The induction of atopic dermatitis-like lesion was conducted by the removal of the back hairs and topical application of 2,4-Dinitrochlorobenzene (DNCB) on to the back skin repeatedly. GMGGT was orally administered at a different dose (10.0 mg/kg, 50.0 mg/kg). Skin reactions, consisting of increased ear thickness and the presence of ear inflammation, were observed in mice over three weeks. Oral administration of GMGGT significantly suppressed the skin lesions, ear swelling, spleen weight, total serum IgE in a concentration dependent manner, and also inhibited the infiltration of mast cells in the dorsal skin. In the present study, these results suggested that GMGGT extract inhibits inflammatory response atopic dermatitis. Therefore, GMGGT may be effective substances for the management of AD in human.

• Korean Journal of Veterinary Service
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• v.36 no.4
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• pp.233-242
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• 2013

The genus Taraxacum, known by the common name Dandelion, is a medicinal herb in the family Asteraceae. It has been traditionally used as a folk medicine for the treatment or prevention of various diseases due to its anti-inflammatory and anti-oxidative properties. In this study, we attempted to evaluate protective effects of Dandelion related with anti-oxidative activity to Thioacetamide (TAA)-induced liver damage. 36 rats were randomly assigned to six experimental groups : Control, Dandelion water extract (DWE), TAA, TAA&DWE 300, TAA&DWE 600, TAA&DWE 1,200 groups. Rats in DWE and TAA&DWE groups were pretreated with DWE (300, 600 or 1,200 mg/kg BW) by gavage for 7 days. All rats were treated intraperitoneally with TAA (200 mg/kg BW) or normal saline at 12 hours after last oral administration and sacrificed at 12 hours after last treatment. Levels of WBC and Neutrophil count were significantly decresed in TAA&DWE 1,200 group compared with that in TAA group (P<0.05). In TAA&DWE 600 and TAA&DWE 1,200 groups, serum AST, ALT, GGT levels were lower than TAA group (P<0.05). The serum TG level was significantly elevated in TAA&DWE groups compared with those in TAA group. Liver tissues from TAA group showed extensive histopathological changes, characterized by moderate or severe hepatocytes degeneration, inflammatory cell infiltration, and congestion. In the TAA&DWE group, The severity of histopathological lesions were decreased compared to those in the TAA group. The MDA concentration was significantly decreased and GSH content was significantly increased in the TAA&DWE 1,200 group compared to those in the TAA group. GR, CAT and GST activities in the TAA&DWE 1,200 group were significantly increased compared to those in the TAA group.

• Journal of Wetlands Research
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• v.13 no.2
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• pp.231-242
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• 2011

Recently, the green spaces in the urban areas were greatly reduced due to urbanization and industrialization. As urban structures such as roads and buildings are built, the amount of impervious area within a watershed increases. High impervious surfaces are the common causes of high runoff volumes as the soil infiltration capacity decreases and the volume and rate of runoff increase thereby decreasing the groundwater recharge. These effects are causing many environmental problems, such as floods and droughts, climate change, heat island phenomenon, drying streams, etc. Most cities attempted to reduce sewer overflows by separating combined sewers, expanding treatment capacity or storage within the sewer system, or by replacing broken or decaying pipes. However, these practices can be enormously expensive than combined sewer overflows. Therefore, in order to improve these practices, alternative methods should be undertaken. A new approach termed as "Low Impact Development (LID)" technology is currently applied in developed countries around the world. The purpose of this study was to effectively manage runoff by adopting the LID techniques. Small Constructed Wetland(Horizontal Subsurface Flow, HSSF) Pilot-scale reactors were made in which monitoring and experiments were performed to investigate the efficiency of the system in removing pollutants from runoff. Based on the results of the Pilot-plant experiments, TSS, $COD_{Cr}$, TN, TP, Total Pb removal efficiency were 95, 82, 35, 91 and 57%, respectively. Most of the pollutants were reduced after passing the settling tank and the vertical filter media. The results of this study can contribute to the conservation of aquatic ecosystems and restoration of natural water cycle in the urban areas.

• Journal of the Mineralogical Society of Korea
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• v.18 no.2
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• pp.135-144
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• 2005

In the high-Ca limestone zone of the Pungchon Formation of the Lower Chosun Supergroup, cryptocrystalline alterations with reddish brown color occur as fissure-fillings or coatings, which was originated from the upper formation, i. e., the Hwajeol Formation. The precipitates result in degradation and contamination of the high-Ca limestone ore in grade and quality, showing characteristic occurrence and mineral composition typical of suggesting a supergene origin. Chalcedonic quartz, kaolinite, illite, goethite and hematite are constituting a characteristic authigenic mineral assemblage and, in places, smectite is less commonly included in the weathering product. In addition to these authigenic phases, some detrital minerals such as mica and orthoclase constituting relatively coarser grains are also rarely present in the supergene alterations. A rather complex clay facies consisting of kaolinite, illite and smectite in the alterations seems to correspond to the typical clay composition of the reported residual pedogenic soils by limestone weathering. The cryptocrystalline weathering product is partly altered to stilbite, a characteristic hydrothermal zeolite, in places, by the hydrothermal contact of late stage. The time of formation and infiltration of the supergene alterations seems to correspond to the stage just after the epithermal alteration of the Pungchon Limestone, i. e., an early Jurassic age. The supergene alteration, which may imply the stage of uplifting, weathering and erosion of the Chosun Supergroup, appears to have undergone at an oxygen-rich environment in descending water of meteoric origin by means of a chemical leaching and diffusion.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.56 no.2
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• pp.140-145
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• 2011

In order to establish the application method of slurry composting & biofilteration liquid fertilizer (SCB LF) in rice cultivation, experiments were studied on split application method of it and effects of it on soil chemical properties and rice yields. Land leveling by rotary tillage within 2 days after application of SCB LF, $NH_4$-N concentration in soil was maintained uniformly in all paddy field. Initial concentrations of $NH_4$-N and $NO_3$-N in soil were high at standard fertilization and 100% application of SCB LF as basal fertilization, however, after tillering stage they maintained similar concentrations in all experimental plots. $NO_3$-N content in infiltration water was slightly lower at 70% application of SCB LF as basal fertilization and 30% application of SCB LF as fertilization at panicle initiation stage than at standard fertilization. Yields of rice by split application of SCB LF were lower at 100% application of SCB LF as basal fertilization, however, those of the other application of SCB LF were similar with that of standard fertilization. In case of rice quality, perfect kernel rates were high and protein contents were lower at non-application and 100% application of SCB LF. Rice quality of 70% application of SCB LF as basal fertilization and 30% application of SCB LF as fertilization at panicle initiation stage were similar with that of standard fertilization.

• Journal of The Korean Society of Grassland and Forage Science
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• v.24 no.3
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• pp.237-244
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• 2004

This experiment was carried out to determine the growth characteristics, dry matter and TDN yield of corn for silage (Zea mays L.), soil nitrate in infiltration water by chemical fertilizer and different manure application(C; chemical fertilizer + chemical fertilizer, T1; Lime +chemical fertilizer + chemical fertilizer, T2; swine manure + swine manure, T3; Lime + swine manure + swine manure, T4; swine manure +chemical fertilizer). The results obtained are summarizes as follows; The mean growth characteristics of T3 treatment(soil treatment: lime + base fertilizer: liquid manure + additional fertilizer: chemical fertilizer) was higher than those of other treatments. The highest yield of dry matter and TDN was obtained in T3 treatment with 18,611 and 13,746 kg/ha, respectively(P<0.05), and the lowest in T1 treatment with 13,529 and 9,541 kg/ha, respectively(P<0.05). The contents of NDF and ADF were not significant different among treatments. However, NDF and ADF content among treatments were the highest with T1 treatment and the lowest with T3 treatment. $NO_3$ level of soil was hardly influenced by the different manure application treatment, and not affected during the experiment time.