• Journal of Korean Society on Water Environment
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• v.36 no.5
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• pp.385-391
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• 2020

Soil loss is a serious problem frequently caused by local torrential rainfalls due to climate change. In particular, soil loss is occurring in agricultural areas rather than urban areas, and many pollutants are introduced into rivers, causing environmental problems. To reduce soil loss, the Ministry of Environment has designated and managed non-point source management areas. The Jaun-district in Hongcheon-gun, which was designed as a non-point pollution source management area in Gangwon-do, is located in the upper stream of Soyang Lake. Most of the agricultural fields are composed of highland agriculture fields. The highland agricultural fields in the Jaun-district are also composed of large-scale farming areas, and the ditches located near the agricultural fields have been illegally used for farmland. Therefore, the local government in Hongcheon-gun is conducting a project to restore the ditches occupied by agricultural fields. However, an analysis of the amount of soil loss that can be reduced by the restoration of the ditches has not been conducted yet. Thus, the purpose of this study was to analyze the effect of reducing the soil loss from the restoration of the ditches used as agricultural fields in the Jaun-district. The SATEEC L Module was used to analyze the reduction in soil loss by ditch restoration. The SATEEC L Module was constructed to estimate the LS factor using Moore and Burch's method after calculating the slope length using the digital elevation model and the maximum allowable slope length. The LS factor and the USLE formula were used to estimate the amount of soil loss that could be reduced by ditch restoration. The analysis showed that the ditch restoration could reduce about 16.6% of the soil loss in the Jaun-district. The results of this study will contribute to the study of methods to reduce soil loss in non-point pollution management areas.

• Journal of Environmental Science International
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• v.24 no.12
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• pp.1617-1627
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• 2015

This study was carried out to investigate the characteristics of suspended solid concentration in small forest watershed, Hwacheon, Gangwondo. For five rainfall events from July 2013 to August 2013, rainfall, discharge, and suspended solid load has been measured. The results showed that the fist flush effect was observed for suspended solid in each rainfall event, sediment rating curve was obtained with $y=30.029x^{1.573}$ at rising limb and $y=12.902x^{1.8827}$ at falling limb, and EMC (event mean concentration) of suspended solid was calculated to 9.4 mg/L. EMC was compared to the values from the watershed that has various land use types and EMC from forest watershed was much lower that from the crop, paddy or low covered forest watershed.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.6 no.3
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• pp.56-68
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• 2003

The main purpose of this study was to verify the shore margin protection effect of the root system of Salix gracilistyla Miq. developed from direct sticking cuttings on wetland, through the measurement of root growth and comparison of soil slaking rate depending on the planting method applied to shore-marginal slope. Comparison of growth rate and soil dispersion rate was made between five planted slope and one naked slope. The planting methods applied to the planted slope were (a) horizontally layed burying of stick(45cm) bundle (b) horizontally layed covering the slope with sticks (c) horizontally fencing with normal cuttings(20cm) (d) elected sticking of normal cutting at equal distances (e) random scattering short cuttings(3-4cm). As results, the most effective planting method was horizontally layed burying, and in order to increase its efficiency scattering the live stem chips in 2-3cm on the slope is recommended. The growth of root was negatively regressive to the distance from water floor.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.6 no.3
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• pp.69-78
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• 2003

The main purpose of this study was to verify the shore margin protection effect of the root system of Salix gracilistyla Miq. developed from direct sticking cuttings on wetland, focusing on the effect of the root system reducing soil particle dissociation rate in water. The soil dissociation rate was examined through slaking tests with cylindric pure soil column at maximum particle density and the same size column of root reinforced soil. The dry weight of remained soil was measured after 5, 10, 15, 30minutes and 1, 6, 12, 24, 48hours inundation. As results, the soil particles began to dissociate severely at 10 minutes and only 10% of soil particles were left after 25minutes inundation. The stable slope angle of pure soil was $36^{\circ}$after 24 hours. On the other hand, the columns of root reinforced soil were stable even after 24hours, being dissociated only 7.2% of soil particles. So, it was revealed that the root system was very effective materials protecting more than 80% of soil particle from dissociation in inundation.

• Earthquakes and Structures
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• v.14 no.5
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• pp.379-388
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• 2018

This study aims to identify the effect of both longitudinal reinforcement details and damage level on making a decision of repairing pre-damaged bridge columns using basalt fiber reinforced polymer (BFRP) jackets. Two RC bridge columns with improper details of the longitudinal and/or transverse reinforcement were tested under the effect of a constant axial load and increasing lateral cyclic loading. Test results showed that the lap-splice column exhibited an inferior performance where it showed rapid degradation of strength before achieving the theoretical strength and its deformation capacity was limited; however, quick restoration is possible through a suitable rehabilitation technique. On the other hand, expensive repair or even complete replacement could be the decision for the column with the confinement failure mode. After that, a rehabilitation technique using external BFRP jacket was adopted. Performance-based design details guaranteeing the enhancement in the inelastic performance of both damaged columns were addressed and defined. Test results of the repaired columns confirmed that both reparability and the required repairing time of damage structures are dependent on the reinforcement details at the plastic hinge zone. Furthermore, lap-splice of longitudinal reinforcement could be applied as a key design-tool controlling reparability and restorability of RC structures after massive actions.

• Restorative Dentistry and Endodontics
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• v.23 no.2
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• pp.639-646
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• 1998

To evaluate the effect of interface conditions and retention grooves in the Class V composite resin restoration of the maxillary first premolar, the distribution of the values of stress and displacement was analyzed with the two-dimensional finite element method. The results were obtained as follows : 1. Boundary elements and Stiffness values could be used as the interface parameters in the, finite element method. 2. The amount of restriction of the displacement at the cervical margin by placing a retention groove at the cervical wall was about three times as high as that by placing a retention groove at the occlusal wall. 3. Because of the relative amount of tensile components of the stress values in the bucco-lingual direction, the possibility of dislocation of the restoration was much higher at the cervical margin than at the occlusal margin. 4. It might be recommended that both occlusal and cervical retention grooves be used routinely, but if one, it be placed at the cervical wall.

• The Journal of Korean Medicine
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• v.36 no.1
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• pp.22-32
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• 2015

Objectives: This study researched the effect of Gamisoyo-san intravenous pharmacopuncture on restoration of liver function after partial hepatectomy in SD rat. Methods: Twelve rats were randomly divided into three groups: control group (n=4) underwent partial hepatectomy, saline group (n=4) was injected $1m{\ell}$ saline after partial hepatectomy, Gamisoyo-san group (n=4) was injected with 10mg/kg Gamisoyo-san after partial hepatectomy. Liver function and liver regeneration ratio were measured on the seventh day after partial hepatectomy. Results: The results show that the AST, AST and ALT level in Gamisoyo-san group was significantly lower than those of control group and saline group(P<0.05) Conclusion: In partial hepatectomy model, Gamisoyo-san intravenous pharmacopuncture seems to significantly promote the restoration of liver function.

• Restorative Dentistry and Endodontics
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• v.26 no.1
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• pp.64-76
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• 2001

Despite the improvements in bond strengths of dentin adhesives and resin-modified glass ionomers, the marginal seal of cervical restorations remains a concern. Microleakage at poorly sealed margins can result in staining, post-operative sensitivity, pulpal irritation, and recurrent caries. The objective of this study was to evaluate the effect of surface penetrating sealant(SPS) on the microleakage of cervical restorations. 45 extracted human teeth were selected, and Class V preparations were prepared on the both buccal and lingual surface of the teeth to the following dimensions : 1.5mm axially, 3mm mesiodistally, and 3mm incisogingivally. After cervical restoration with composite resin, compomer, glass ionomer each restoration was treated as three methods: No Tx., Scotchbond Multipurpose Adhesive$^{\circledR}$, Fortify$^{\circledR}$. The sections were examined with a stereomicroscope to determine the extent of microleakage at enamel and dentin margins. The results of this study were as follows. 1. All groups showed some microleakage. 2. Gingival cavity wall with cementum margin showed significantly higher leakage value than occlusal cavity wall with enamel margin. 3. The group treated with SPS showed significantly lower leakage value than no treated group(p<0.05). But there is no difference between Fortify$^{\circledR}$ and Scotchbond Multipurpose adhesive$^{\circledR}$. The results of this study suggest that SPS are effective in reducing microleakage of class V restorations. But it is certain that some microleakage still occurred despite the application of SPS.

• PNF and Movement
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• v.3 no.1
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• pp.17-26
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• 2005

Objectives : The purpose of this study is to identify influence that PNF method have an effect in function restoration of the impaired patients of central nervous system. Methods : The data were collected by 15 adult stroke patients. The treatment was based on proprioceptive neuromuscular facilitation techniques. Temporal and spatial parameters of gait were analysed for using the computerized GAITRite system. Results : In the comparison of functional ambulation profile(FAP) before and after experiment, the FAP was significantly increased in the PNF method. The gait velocity, cadence and single support time asymmetry ratio was significantly increased in the PNF method. The Motor Assessment Scale was significantly increased in the PNF method. Conclusions : Based on these results, it is concluded that the forced PNF method for 6 weeks can be improve the temporal-spatial gait parameters including FAP in hemiplegic patients. Therefore, the forced PNF method is useful to improve the function restoration in hemiplegic patients. Further study should be done to analyze the effects of intervention duration of treatment, optimal time to apply the treatment in more long peried.

• Journal of Environmental Impact Assessment
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• v.26 no.6
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• pp.508-523
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• 2017

This study monitored the changes before and after restoration of ecological stream focusing on the places which are applied Sustainable Structured wetland Biotop (SSB) system and ecological Fish-way for restoration of Maeno stream. A total of 11 species and 191 individuals of fishes were founded out which were not verified inhabitation before restoration at SSB wetlands. Especially, it was could identified that micro habitat and healthy Fish-way was created because the restored target species, Microphysogobio yaluensis and Iksookimia koreensis were identified that habitation was monitored in SSB wetland. Amphibian have been restored to a number of Rana nigromaculata found in and around wetlands at the time of the third survey, which is highly active after restoration. Specified endangered species class 1 and natural monuments designated by the Ministry of Environment, Lutra lutra lutra, as a Mammalian, uses the wetlands and ecological Fish-way as habitat areas, and the his habitat is restored. In the case of Flora, vascular plants emerging in the survey area were increased to 7 and 13 species before restoration and 15 and 19 species directly after restoration, and 22 species and 33 species after restoration. Vegetation after restoration was found to be a basic producer of various ecosystems and a plant community that contributes to the purification of water quality such as Phragmites japonica communities. As the result of water quality monitoring, the average of treatment efficiencies were BOD 64.3%, T-N 47.2%, T-P 80.7%. Successful treatment of the nonpoint pullution source, which is a limiting factor to disturb the ecosystem, creatively restored the target species in the water quality class I, II.