• Journal of the Korean Geotechnical Society
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• v.39 no.7
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• pp.57-67
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• 2023

Slope failures during rainfall have been observed in mountainous areas of South Korea as a result of the presence of solar power facilities. The seepage behavior and pore pressure distribution differ from typical slopes due to the presence of impermeable solar panels, and the load imposed by the solar power structures also affects the slope behavior. This study aims to develop a method for evaluating the stability of slopes with solar power facilities and to analyze vulnerable points by considering the maximum slope displacement. To assess the slope stability and predict behavior while considering rainfall seepage, a combined seepage analysis and finite difference method numerical analysis were employed. For the selected site, various variables were assumed, including parameters related to the Soil Water Characteristic Curve, strength parameters that satisfy the Mohr-Coulomb failure criterion, soil properties, and topographic factors such as slope angle and bedrock depth. The factors with the most significant influence on the factor of safety (FOS) were identified. The presence of solar power facilities was found to affect the seepage distribution and FOS, resulting in a decreasing trend due to rainfall seepage. The maximum displacement points were concentrated near the upper (crest) and lower (toe) sections of the slope.

• Journal of Periodontal and Implant Science
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• v.29 no.4
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• pp.873-893
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• 1999

The ultimate goal of periodontal therapy is the regeneration of periodontal tissue and repair of function. For more than a decade there have been many efforts to develop materials and bioactive molecule(such as growth factor and differentiation factors) to promote periodontal wound healing. Among the bioactive molecules, bone morphogenetic protein(BMP) was studied for periodontal wound healing. Since Urist demonstrated that demineralized bone matrix could induce the formation of cartilage and bone in ectopic site, many studies on BMP have been reported. Among those BMPs, it was reported that rhBMP-2 enhanced the healing of bone defects in animal studies and clinical studies. However, its efficacy in periodontal regeneration, especially 1-wall intrabony defects is still unknown. The purpose of this study was to examine the effect of rhBMP-2/ACS on the epithelial migration, gingival connective tissue adhesion, cementum formation, alveolar bone regeneration in intrabony defects of dogs. Four millimeter deep and four millimeter wide 1-wall defects were surgically created in the mesial aspects of the 3rd incisors. The test group received rhBMP-2/ACS with a flap procedure and the control underwent buffer/ACS with a flap procedure. Histologic analysis after 8 weeks of healing revealed the following results: 1. The length of epithelial growth(the distance from alveolar crest to the apical end of JE) was $0.9{\pm}1.5mm$ in the control group and $1.2{\pm}1.4mm$ in the test group. There was no statistically significant difference between the two groups. 2. The length of connective tissue adhesion was $2.4{\pm}1.3mm$ in the control group and $1.2{\pm}1.1mm$ in the test group. The control group showed significantly enhanced adhesion(P<0.05). 3. The length of new cementum was $0.9{\pm}1.0mm$ in the control group and $1.7{\pm}0.8mm$ in the test group. The test group showed significantly enhanced cementum regeneration(P<0.05). 4. The length of new bone height was $1.9{\pm}0.6mm$ in the control group and $2.4{\pm}0.9mm$ in the test group. There was no statistically significant difference between the two groups. 5. The new bone area was $4.7{\pm}1.7mm^2$ in the control group and $8.0{\pm}2.0mm^2$ in the test group. The test group showed significantly enhanced bone formed area(P<0.05). 6. The new bone density was $73.0{\pm}8.6%$ in the control group and $66.6{\pm}15.3%$ in the test group. There was no statistically significant difference between the two groups. These results suggest that the use of rhBMP-2 in 1-wall intrabony defects has significant effect on new cementum and new bone formation area, but doesn't have any significant effect on the prevention of junctional epithelium migration and new bone formation height.