• Journal of the korean academy of Pediatric Dentistry
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• v.33 no.2
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• pp.323-328
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• 2006

Dentinogenesis imperfecta is an inheritable disease of dentinal defect, generally is inherited as a single autosomal dominant trait. It has a prevalence of 1 in 8000 with the trait, and no significant difference between male and female, with involvement of the primary and permanent teeth. Shields proposed three types of Dentinogenesis imperfecta. Affected teeth have various discoloration, separation of enamel rapid destruction of underlying dentin, and severe attrition. Radiographically, the teeth have cervical constriction, bulbous crown, thin root, obliteration of the root canals and pulp chambers, and periapical lesions in a sound tooth. The objective of treatment is rehabilitation of the esthetics, the masticatory function, and the vertical dimension of occlusion. In these cases, two pediatric patients reported to the Kyungpook University Pediatric clinic, with a chief complaint of discolored teeth and severe attrition. As a result of clinical and radiographic exam, it was diagnosed as Dentinogenesis imperfecta. The posterior teeth were restored with Stainless Steel Crown, and the anterior teeth were restored with composite resin veneering.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.817-820
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• 2008

The river environments of many streams in korea have been deteriorate through the rapid industrialization and urbanization since the 1960s. In korea, on the other hand, much efforts on the research and project have been made for the restoration of the deteriorated streams to close-to-nature. in order to restore the deteriorated streams, therefore, it is necessary to investigate such advanced technologies and materials. In view of this requirement, various research paths are being taken focusing on coarse aggregates to make multi-functional porous concrete having continuous voids so as to improve water and air permeability, acoustic absorption, water purification and applicability to vegetation. The Purpose of this study is to investigate the method for recovery of the environment in the streams area using porous concrete retaining wall block. the multi-P.O.C block applies for test in the Jangduri-cheon have been monitored planting, stability etc. after 6 months, plant grows flourishing and reconstructed in state such as nature rivers.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.40
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• pp.35.1-35.7
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• 2018

Background: After the resection at the mandibular site involving oral cancer, free vascularized fibular graft, a type of vascularized autograft, is often used for the mandibular reconstruction. Titanium mesh (T-mesh) and particulate cancellous bone and marrow (PCBM), however, a type of non-vascularized autograft, can also be used for the reconstruction. With the T-mesh applied even in the chin and angle areas, an aesthetic contour with adequate strength and stable fixation can be achieved, and the pores of the mesh will allow the rapid revascularization of the bone graft site. Especially, this technique does not require microvascular training; as such, the surgery time can be shortened. This advantage allows older patients to undergo the reconstructive surgery. Case presentation: Reported in this article are two cases of mandibular reconstruction using the ready-made type and custom-made type T-mesh, respectively, after mandibular resection. We had operated double blind peer-review process. A 79-year-old female patient visited the authors' clinic with gingival swelling and pain on the left mandibular region. After wide excision and segmental mandibulectomy, a pectoralis major myocutaneous flap was used to cover the intraoral defect. Fourteen months postoperatively, reconstruction using a ready-made type T-mesh (Striker-Leibinger, Freibrug, Germany) and iliac PCBM was done to repair the mandible left body defect. Another 62-year-old female patient visited the authors' clinic with pain on the right mandibular region. After wide excision and segmental mandibulectomy on the mandibular squamous cell carcinoma (SCC), reconstruction was done with a reconstruction plate and a right fibula free flap. Sixteen months postoperatively, reconstruction using a custom-made type T-mesh and iliac PCBM was done to repair the mandibular defect after the failure of the fibula free flap. The CAD-CAM T-mesh was made prior to the operation. Conclusions: In both cases, sufficient new-bone formation was observed in terms of volume and strength. In the CAD-CAM custom-made type T-mesh case, especially, it was much easier to fix screws onto the adjacent mandible, and after the removal of the mesh, the appearance of both patients improved, and the neo-mandibular body showed adequate bony volume for implant or prosthetic restoration.

• Korean Journal of Environment and Ecology
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• v.29 no.2
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• pp.132-144
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• 2015

Yongneup wetland protected area, the only high moor in Korea, is a core area to conserve biodiversity. Even though the Yongneup wetland protected area is relatively small, various plant species are distributed in the Yongneup wetland protected area because it includes various habitats showing different environmental gradients. Vascular plants distributed in the Yongneup wetland protected area were identified as a total of 376 taxa that is composed of 73 families, 217 genera, 322 species, 3 subspecies, 44 varieties and 7 forms. For endangered plants designated by the Ministry of Environment, 5 species including Trientalis europaea var. arctica, Lilium dauricum, Halenia corniculata, Lychnis wilfordii and Menyanthes trifoliata were found and 34 taxa were confirmed to be distributed only in the mountainous wetland habitats. Regarding naturalized plants, a total of 11 taxa were distributed, but most of them were distributed in the areas where artificial interference has occurred. And in areas inside the wetlands that are relatively well preserved, 2 species of Bidens frondosa and Erigeron annuus were observed. In this study, the occurrence and distribution of Pseudostellaria baekdusanensis M. Kim, which was recently found in Mt. Baekdu and reported as a new species, were identified in the Yongneup wetland protected area. A wetland is a very vulnerable area to drastic environmental changes and damages to its ecosystem could cause the extinction of rare plant species which are distributed only in the wetlands. Therefore, it is mandatory that current status of the Yongneup wetland protected area is evaluated and actions to prevent rapid environmental changes are taken. Fourteen separate investigations were conducted in 2013 and another four in 2014, to evaluate current status of the Yongneup wetland protected area. These investigations have provided us the basic information for future actions of conservation and restoration.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.27 no.6
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• pp.639-647
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• 2009

In line with the rapid settlement of information society, the demand for geospatial information and its applications are dramatically increasing. The Project of National Geographic Information System(NGIS) is actively on going to meet up-to-dateness and accuracy of geospatial data. It is fact that the public interest in environmental issues is increasing than ever in accordance with the restoration of the four major rivers, core project of Green New Deal Policy, and the event of the Ramsar General Meeting. Because the Nakdong River Estuary is a place of great importance in both aspects of wetland and environment conservation, a variety of researches related to this area are progressing. Although artificial developments and natural phenomena are rapidly changing the topography and ecosystem of this area, the effort to build topographic DB for change monitoring is very slow. This study describes a Lidar surveying project over the restored wetland Eulsukdo, the southermost part of the Nakdong River, to establish precise topographic DB throughout producing 3D topographical maps and wetland classification maps. The results of this study will make a large contribution to the systematic maintenance and management for the restored Eulsukdo wetland.

• Journal of the Korean Geosynthetics Society
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• v.16 no.2
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• pp.23-33
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• 2017

Due to the rapid development of cities, densities and heights of urban structures are increased, and much larger and more underground spaces are being developed accordingly. Increasing development of underground spaces has induced more ground sinks and underground cavities. Therefore, safety of people is threatened by potential ground collapses and possible accidents, which may result from underground cavity. To actively respond against potential danger of ground sink, evaluation of existing cavity grade and development of recovery procedure are important. There exists the ground sinking management grade system of expressway developed as local standards in Japan. Recently, ground sinking management grade system of Seoul was developed with consideration of road and asphalt conditions. In this study, 209 underground cavities of ${\bigcirc}{\bigcirc}$ area were explored and their cavity shapes and grades were evaluated based on both ground sinking management grade systems of Japan and Seoul. Comparison is made between cavity grades evaluated based on both grading systems from Japan and Seoul. As a result of comparative analysis, the conservatively-estimated cavity grades requiring emergency restoration based on the Japanese management grade system of expressway result from neglection of layer thickness of surface pavement, considering only width and cover depth of a cavity.

• Journal of Conservation Science
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• v.34 no.1
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• pp.11-21
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• 2018

The result of the study on the origin and preservation status of the 'Gongju Junghakdong old missionary house', the Registered Cultural Property No. 233, reveals that the building was approved on October 23, 1921, and missionary Alice H. Sharp was living in the building until her retirement from her missionary life of 39 years in Korea in 1939. In order to review internal and external preservation status of the building, condition of wood material, the composition of the window, the damage of the wall, and the leaning of the building were examined. In particular, in the case of window facilities, it is necessary to restore it to the original upper and lower sliding window. As a result of investigation of the preservation status of the external facilities, it is necessary to restore the original shape of the staircase and a deck of the building on south western side and the well. In addition, the results of the non-destructive diagnosis of the ground revealed that the building was built on uneven surface layer of 2-5 m thickness and the boundary between the surface layer and the upper part of the weathered rock is inclined following geomorphology. This phenomenon shows that when the water content of the ground increases in the rainy season, the bearing capacity of the ground is lowered, and there is a possibility of uneven subsidence. Especially, landslides may occur in case of heavy rain. Therefore, it is desirable to install a masonry facility at the southwest boundary of the site, and it is recommended to install a drainage facility to ensure rapid drainage.

• Journal of Soil and Groundwater Environment
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• v.19 no.3
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• pp.33-38
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• 2014

This study was performed to evaluate the applicability of pump and treat technology as well as to identify the changes of groundwater level by continuous pumping at the petroleum contaminated site. A total of 9 monitoring wells were installed at the site and the contaminant concentrations, TPH, benzene, toluene, ethylbenzene and xylene, of groundwater were measured. With the results of the groundwater monitoring, a total of 9 wells were set up for pumping contaminated groundwater in 3 locations. The waste water treatment facility with a capacity of $10m^3/hr$ was installed in the site and operated for about 1 year. The concentrations of the contaminated groundwater from the 3 pumping wells were exceeded groundwater regulation for benzene and TPH. However, the effluent concentration of benzene and TPH was under the regulation showing the maximum level of 0.011 mg/L and 1.2 mg/L during the operation periods. Groundwater levels were decreased by continuous pumping and those were not recovered during the operation period. Groundwater levels of PW-1,2, PW-3,4,5,6 and PW-7,8,9 were decreased about 5 m, 0.7 m, 2 m, respectively. The hydraulic conductivity (K) of the region of PW-1,2, PW-3,4,5,6 and PW-7,8,9 was estimated to be $6.143{\times}10^{-5}cm/sec$, $2.675{\times}10^{-5}cm/sec$, $1.198{\times}10^{-4}cm/sec$. Groundwater level was seemed to be affected not by hydraulic conductivity but by morphological effect. These results show that the pump and treat technology has high applicability for the restoration of petroleum contaminated groundwater but needs continuous monitoring to prevent rapid groundwater drawdown.

• Journal of the Korean Society of Food Culture
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• v.3 no.4
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• pp.397-406
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• 1988

The changes in the dietary pattern of Koreans during the last one century and its consequences are summarized as follows; 1. Until the beginning of 20th century, Koreans used variety of cereals, vegetables and fruits for their staple food, but the variety has been largely reduced by the agricultural development and urbanized life style. 2. The well balanced traditional dietary pattern of Korean had been deeply deteriorated by the food shortage during the Japanese occupation and Korean war. 3. The deteriorated nutritional condition of Korean was not remedied by the restoration of traditional dietary pattern, but attempted to overcome it by the adoption of Western food habit. 4. The people were trained to eat milk and flour-meals during the starvation of Korean war, and it was continued after Korean war through the animal husbandry promotion policy. 5. The importation of food and feed cereals has been increased rapidly during the economic growth in 1970's and the food self-sufficiency droped below 50%. 6. In 1970's, the food supply pattern of Korean was restored to the level of early 1900, but the consumption of lipid increased extraordinarily. 7. The overconsumption of animal food and lipid continues in 1980's, and it coincides with the rapid increase in the occurence of food related degenerative deseases. 8. The establishment of Korean dietary goal which is based on the traditional dietary pattern is needed.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.31 no.5
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• pp.203-211
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• 2021

Octacalcium phosphate(OCP, Ca₈H₂(PO₄)₆·5H₂O) is one of biodegradable calcium phosphate materials with osteoconductivity and biocompatibility. It has the advantage of rapid bone formation and resorption due to the property of stimulating stromal cells to differentiate into osteoblasts. However, if OCP is inserted in body, it is immediately decomposed without maintaining of its shape as scaffolds due to their weak cohesive force between powder. On the other hand, hydroxyapatite (HA, Ca₁₀(PO₄)₆(OH)₂), which has a crystal structure similar to that of OCP, remains in the body without decomposition until the bone defect is restored. In this study, the degradation behavior of OCP/HA disc with different amount of HA in SBF (simulated body fluid) solution was characterized in terms of the weight loss, pH variation and microstructure change with immersion duration in SBF solution. As a result, the OCP/HA disc was not quickly decomposed and maintained its own shape for 2 weeks regardless of HA content. In particular, the surface of 40HA specimen was uniformly dissolved and then CDHA (calcium deficient hydroxyapatite) phase were formed onto the surface of disc after 7 days in SBF solution. It would be suggested that the 40HA specimen would be suitable candidate material as the scaffolds for the restoration of bone defect.