• Journal of the Korean Society of Environmental Restoration Technology
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• v.1 no.1
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• pp.141-150
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• 1998

This study was conducted to find out the possibility of seeding of Zoysia japonica and woody plants for the revegetation of rock-exposed-cutslopes by Natural Topsoil Restoration Methods (NTRM). The 5cm thick layer of artificial soil was attached at rock-exposed cutslopes for the growth of Zoysia japonica and native woody plants by NTRM. The main results were summarized as follows. 1. Artificial soil attached at rock-exposed-slopes by NTRM was not eroded until recovered by Zoysia japonica and native woody plants. It shows extremely low soil erodibility. 2. One year later after seeding, woody plants show 100% ground coverage. But, in early stage, they grew more quickly at northwest slopes than at southeast slopes. 3. In seeding of Zoysia japonica, it grew more quickly at southeast slopes than at northwest slopes. Also, it grew better at lower part of the slopes than at middle part of the slopes. 4. After one year from seeding, the height of Lespedeza cyrtobotrya and Indigo/era pseudo-tinctoria were longer than any other plants. The next were Albizzia julibrissin, Lespedeza cuneata and wild flowers. The tree height of Rhus chinensis shows 28cm length, so it has enough possibility to be used for roadside revegetation works. 5. Lespedeza cyrtobotrya and Indigo/era pseudo-tinctoria show different importance values according to slope aspect. But, they show tendency to outweigh the other plants at all slope-aspects. 6. Most of the plants seeded by NTRM were germinated well and they covered rock-exposed-slopes so quickly and effectively. Thus it leads to conclusion that the revegetation methods used in this experiment was a very effective methods to recover rock-exposed-slopes by seeding of zoysia japonica and native woody plants.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.13 no.1
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• pp.1-13
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• 2010

This study was accomplished to identify and analyze vegetation structure of Mountainous Wetlands in Dan-yang and around area, and surveyed from September to November, 2006. 6 sites of total 16 potential Mountainous Wetlands by GIS based wetland forecasting system (Korea National Arboretum, 2006) were identified as wetlands throughout field survey by the indicators such as hydrology, soil and vegetation. By classification system of Korea National Arboretum (2006), types of wetlands were classified into 3 slope-types and 3 flat-types. To understand vegetation structure of wetlands, height, DBH (diameter at breast height), DI (Dominance Index), sociability and constancy were surveyed and the projection diagram and charts ware drawn. As results, Salix koreensis in woody plant layer and Persicaria thunbergiiin and Juncus effusus var. decipiens in herb layer were surveyed as broadly distributed species. The wetlands of Dan-yang around area were similar to those of Chung-ju around area, but the species of plants and hydrology conditions were different. This study is mainly focused on vegetation condition of Mountainous Wetlands. But, further studies on functional assessment for management and restoration of wetlands were necessary.

• International Journal of Contents
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• v.8 no.3
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• pp.34-41
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• 2012

The concept of vegetation freeboard equivalence (VFE) is presented from the comparison between the rise in stage with/without vegetation and the freeboard height under design discharge conditions. In South Korea, the freeboard height of large, medium and small rivers is defined as a function of river discharge. Two models are used for this analysis of flood stage with and without vegetation: the 1-D model HEC-RAS and the 2-D model RMA-2. Both models are applied to three river study sites of the Geum River in South Korea as representative sites for a large, a medium and a small river. The analysis shows that without vegetation, both models provide comparable results and the calculated results are in very good agreement with the design configuration. The vegetation effects on the medium river are less significant, and the freeboard is adequate to contain the rise in stage from the added floodplain vegetation in large rivers. The concept of vegetation freeboard equivalence is therefore useful for the analysis of flood river stages after the restoration of channels with increased floodplain vegetation.

• Archives of Craniofacial Surgery
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• v.10 no.2
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• pp.103-108
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• 2009

Purpose: Although there are many reports on the development of paranasal sinuses, few studies were performed with respect to the frontal sinus with 3D CT, especially in Korean children. In this study, we evaluated the normal development of frontal sinus in Korean children with 3D CT imaging. Methods: A total of 301 patients under the age of 20 were reviewed retrospectively. Maximal AP (anteroposterior) length, height and width were measured with the aid of computer device. The volume of frontal sinus was also evaluated. Results: At the age of more than 4, the pneumatization of frontal sinus was detected. Frontal sinus developed continuously and was observed in almost every children at the age of more than 17. The AP length, height, width and volume of frontal sinus were enlarged continuously until the age of 20. And the maximal growth of frontal sinus was observed at puberty. The width and volume of frontal sinus showed high correlation coefficient (r=0.8) relative to height or AP distance. Conclusion: The results of this study may be helpful in the comprehension of normal development of frontal sinus in Korean children.

• Archives of Plastic Surgery
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• v.38 no.5
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• pp.674-678
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• 2011

Purpose: Straight closure line of classic Weir excision leaves visible scars and makes it difficult to precisely approximate resection margins. Hence this study introduces Park-Weir excision that effectively reduces alar width with minimal alar rim scar by 3-dimensional zigzag incision and properly controls the approximation of edges. Methods: From 2008 to 2010, 14 patients underwent Park-Weir excision, crossed wedge excision on alar rim not exceeding 5 mm in width. Each patient was photographed in the same position. Alar width and columellar height against intercanthal distance was compared preoperatively and postoperatively, using image analysis software. Results: Five patients were female and nine were male. Average follow up period was 8 month. Alar width was reduced by 50.50% to 45.96%, original alar width reduced by 8.98% without significant changes in columellar height which was reduced by 0.39%. No visible scar was reported during outpatient follow-up. Conclusion: Park-Weir excision effectively reduces alar width and corrects the flaring of alar without affecting the columellar height. Zigzag incision of Park-Weir excision leaves aesthetically more pleasant scar than straight single incision of classical Weir excision.

• Journal of Korean Neurosurgical Society
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• v.55 no.6
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• pp.337-342
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• 2014

Objective : To determine deformity correction by postural correction and subsequent balloon inflation in acute vertebral compression fractures (OVCFs) and to examine the effect of bone mineral density on deformity correction. Methods : A totol of 50 acute OVCFs received balloon kyphoplasty. Lateral radiographs were taken and analyzed at five different time points : 1) preoperative, 2) after placing the patient in prone hyperextended position, 3) after balloon inflation, 4) after deposition of the cement, and 5) postoperative. All fractures were analyzed for height restoration of anterior (Ha), middle (Hm) and posterior (Hp) vertebra as well as Cobb angle and Kyphotic angle. The bone mineral density (BMD) of lumbar spine was measured by dual-energy X-ray absorptiometry. According to the T-score, the patients were divided into two groups which were osteoporosis group and osteopenia group. Results : Postoperative measurements of Ha, Hm and the Cobb angle demonstrated significant reduction of 4.62 mm, 3.66 mm and $5.34^{\circ}$ compared with the preoperative measurements, respectively (each p<0.05). Postural correction significantly increased Ha by 5.51 mm, Hm by 4.35 mm and improved the Cobb angle by $8.32^{\circ}$ (each p<0.05). Balloon inflation did not demonstrate a significant improvement of Ha, Hm or the Cobb angle compared with baseline prone hyperextended. Postural correction led to greater improvements of Ha, Hm and Cobb angle in osteoporosis group than osteopenia group (each p<0.05). Conclusion : In acute OVCFs, the height restoration was mainly attributed to postural correction rather than deformity correction by balloon inflation. BMD affected deformity correction in the process of postural correction.

• The Journal of Advanced Prosthodontics
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• v.1 no.3
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• pp.140-144
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• 2009

STATEMENT OF PROBLEM. Little information is available about the buccal gingival level of multiple implant restorations. PURPOSE. This study was aimed to evaluate the relationship between width and height of buccal soft tissue around single and 2 adjacent implant restorations. MATERIAL AND METHODS. Four implant restoration groups (first and second molars, single second molars, posterior single restorations between teeth, and anterior single restorations between teeth) were randomly chosen from one dental institute. Each group comprised of 6 patients. After 6 months of function, silicone impressions were taken and stone models were fabricated for each restoration group. The stone models were cut in bucco-lingual direction at the most apical point of buccal gingival margin. The height and width of buccal supra-implant soft tissue were measured. One way ANOVA and Tukey HSD post hoc tests were performed to analyze the data obtained (P < .05). RESULTS. The most unfavorable width-height ratio was noted for the group, which was comprised of the second molar in the multiple adjacent (first and second molar) implant-supported restorations. The group also resulted in the shorter height of buccal supra-implant mucosa rather than that of anterior single implant restorations between natural teeth. CONCLUSION. To achieve a favorable level of buccal gingival margin, greater thickness of buccal supra-implant mucosa is required for the implant restorations without a neighboring natural tooth compared to the implant restorations next to a natural tooth.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.15 no.6
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• pp.29-41
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• 2012

This study was conducted in Ningxia Hui autonomous region, located at southern part of Mu Us sand land in China. To investigate relationships between windbreak effect and installation cost of sand barriers, plastic net is utilized by using four kind of heights (0.2, 0.3, 0.4 and 0.5m) and four kind of porosities (20, 30, 50 and 70%). These heights and porosities are measured for estimating distances for effective windbreak. It is shown that porosity and the distance have a positive relationship at same heights and porosity on ground indicates a constant figure when height reaches a certain level, regardless of the porosity. This implies that there is a difference of level of windbreak with different porosities; however, distance of windbreak effect is same at the same height of sand barrier. As a result of comparison between porosity of sand barrier on the ground and installation cost in each sand barrier with various heights and porosities (16 combinations), 0.4m and 0.5m height sand barriers describe highest economical efficiency. Within two variables, we concluded that height has a higher impact on windbreak effect than porosity.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.8 no.5
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• pp.19-27
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• 2005

The earth is a huge magnet. All organisms live under the magnetism of earth. The magnetism influences the ions in the cells of organisms and variously functions to lives as well. The medical treatment with magnet has come down from the ancient, it has an effect on the plants' growth. But there are no scientific studies about the influences of magnetism on plant growth. Accordingly, the experiment about the influence of magnetism on several foliage plants was carried out in this study. The promotion of plants' growth led by magnetism will be the method to save the management cost of horticultural market by early shipment. As a results of this experiment, plants treated with magnets showed excellent growth especially in length growth. The experiment results of the respective plants are the following. 1. Rhapis flabelliformis : This have grown so very well in the container lined with magnets as time goes by. Showing the significant(p<0.05) differences, the length growth of Height and Length of leaves was especially distinguished. 2. Howea belmoreana : This has grown well in all containers. Showing the significant(p<0.05) differences, the length growth of Height and Length of leaves was especially distinguished. 3. Chamaedorea seifrizii : There have been the growth differences between Height and Length of leaves as time goes by. The growth of Height and Length of leaves in the container lined with magnets has been excellent. The number of leaves and number of branch generally had no big differences but the growth of Height and Length of leaves was excellent in the magnet container. The method of plant growth promotion with magnet should save the management cost for this reason. Therefore the succeeding studies about the plant growth under the influence of magnet intensity and kind must be performed. The studies with various plants are needed to activate the program for growing plants with magnet.

• Journal of Korea Water Resources Association
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• v.53 no.1
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• pp.29-43
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• 2020

The purpose of this study is to propose the design criteria and detailed design model by reviewing the issues related to geometry, formation process, destruction process, hydraulic function, restoration and ecological function of the step-pool from the existing research results, to apply the step-pool sequences to river restoration. Based on the analysis and review results, the design criteria for the structure and size of the step-pool are presented as ratio of the step spacing and the channel width, ratio of the unit step slope and channel slope, and ratio of step height and the particle size. To ensure structural stability of the step, stability analysis method of overturning based on the keystone theory was proposed as a design criterion. As a detailed design concept, a layout model was proposed by applying the imbricating structure of keystones and arch stones to the planar, longitudinal and transverse configurations of the step-pool.