• KSCE Journal of Civil and Environmental Engineering Research
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• v.41 no.4
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• pp.365-376
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• 2021

In general, domestic streams and rivers are composed of alluvial rivers consisting of sand and gravel beds. These rivers can cause erosion and riverbed changes due to sudden changes in flow rates, such as floods, torrential rains, and heavy rains. In particular, there are various types of erosion, such as contraction erosion caused by changes in river shape, or local erosion occurring around obstacles such as piers, abutments or embankments. In addition, river changes can occur in various forms, such as static or dynamic periods, due to limitations such as flow rate, velocity, and shear stress. This study focused on the erosions of embankments directly related to human casualties among various river structures, and evaluated limit velocities and critical shear stress in order to identify changes in strength of natural materials by identifying the characteristics of natural hoan materials and resistance to erosions. In particular, the limitations of materials according to the type of materials in the river, characteristics of particles, and size of particles were studied using Soil loss, which is a change in the volume of the revetment material, and it is intended to be used as basic data for river design and restoration.

• The Journal of Korean Academy of Prosthodontics
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• v.57 no.3
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• pp.288-295
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• 2019

Passive fit of prosthesis is an essential property of implant supported prosthesis for long term success and minimization of complications. And the property is determined mostly by fabrication procedure. There were limitations of extensive implant prosthesis because conventional casting method generate contraction error of long span prosthesis. However, Computer-aided design/Computer-aided manufacturing (CAD/CAM) technology of 3D printing and milling metal framework can overcome those limitations. This case is a full mouth rehabilitation using extensive implant fixed prosthesis. Removable interim prosthesis was made for esthetic, functional evaluation and a guide for implant insertion. After the insertion, implant fixed interim prosthesis was delivered. After additional evaluation and adjustment, final prosthesis was designed with CAD, the fabricated with CAM. Milling technique was used for anterior screw type implant superstructure and 3D printing technique was used for the anterior and posterior implant copings. Fit of the final restoration was favorable. The practitioner and patient were both esthetically and functionally satisfied with the final result.

• Journal of the korean academy of Pediatric Dentistry
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• v.46 no.1
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• pp.76-84
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• 2019

This study evaluated the microleakage of three restorative materials and three tricalcium silicate-based pulp capping agents. The restorative materials were composite resin (CR), resin-reinforced glass ionomer cement (RMGI), and traditional glass ionomer cement (GIC) and the pulp capping agents were TheraCal $LC^{(R)}$ (TLC), $Biodentine^{(R)}$ (BD), and $ProRoot^{(R)}$ white MTA (WMTA). Additionally, shear bond strengths between the pulp-capping agents and dentine were compared. Class V cavities were made in bovine incisors and classified into nine groups according to the type of pulp-capping agent and final restoration. After immersion in 0.5% fuchsin solution, each specimen was observed with a stereoscopic microscope to score microleakage level. The crowns of the bovine incisors were implanted into acrylic resin, cut horizontally, and divided into three groups. TLC, BD and WMTA blocks were applied on dentine, and the shear bond strengths were measured using a universal testing machine. The microleakage was lowest in TLC + GIC, TLC + RMGI, TLC + CR, and BD + GIC groups and highest in WMTA + RMGI and WMTA + CR groups. The shear bond strength of BD group was the highest and that of WMTA group was significantly lower than the others.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.37 no.1
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• pp.33-40
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• 2019

The purpose of this study is to analyze historical records of what the trees had been planted like by establishment and management of the Royal Tombs of the Joseon Dynasty so that it could be utilized for historical records to manage the trees in the Royal Tombs. The research method was to analyze the related keywords for 40 trees out of 42 trees in the Royal Tombs of the Joseon Dynasty reffering to "The Annals of the Joseon Dynasty(朝鮮王朝實錄)," and "Neungji(陵誌)". There are two types of planting called Jeongsik(定植) Bosik(補植) in the Royal Tombs. Jeongsik(定植) is a planting method by Salleungdogam(山陵都監), the office in charge of construction of the royal tomb when they were building the royal tomb. Every tree additionally planted after building up the royal tomb was called Bosik(補植). The types of tree planting the composition and management of the royal tombs of Joseon are as follows. First, the first planting for landscaping was carried out during the process of building the province. Second, after the formation of Shanung, all the plants were planted by Wangmyung as additional plants. Third, due to the deforestation in the late Joseon period, additional plants were planted in the fertile plains. Fourth, trees were damaged due to natural disasters, and trees were planted together with the construction of the botanical gardens. Fifth, in the 22nd year of King Jeongjo, all the royal families' graves were regularly planted. This study aims to investigate the history of forest landscape management for the restoration of the royal tombs of Joseon.

• Journal of Cadastre & Land InformatiX
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• v.51 no.1
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• pp.111-124
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• 2021

Recently, Interest in the restoration and 3D reconstruction of cultural properties due to the fire of Notre Dame Cathedral on April 15, 2019 has been focused once again after the 2008 Sungnyemun fire incident in South Korea. In particular, research to restore and reconstruct the actual measurement of cultural properties using LiDAR(Light Detection and ranging) and conventional surveying, which were previously used, using various 3D reconstruction technologies, is being actively conducted. This study acquires data using unmanned aerial imagery of UAV(Unmanned Aerial Vehicle), which has recently established itself as a core technology in the era of the 4th industrial revolution, and the existing CRP(Closed Range Photogrammetry) and terrestrial LiDAR scanning for the Recumbent Buddha of Unju Temple. Then, the 3D reconstruction was performed with three fusion models based on SfM(Structure-from-Motion), and the reproducibility and accuracy of the models were compared and analyzed. In addition, using the best fusion model among the three models, the relationship with the Polar Star(Polaris) was confirmed based on the real world coordinates of the Recumbent Buddha, which contains the astronomical history of Buddhism in the early 11th century Goryeo Dynasty. Through this study, not only the simple external 3D reconstruction of cultural properties, but also the method of reconstructing the historical evidence according to the type and shape of the cultural properties was sought by confirming the historical evidence of the cultural properties in terms of spatial information.

• Conservation Science in Museum
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• v.25
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• pp.51-62
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• 2021

The Belt with Rhinoceros-Horn Ornaments(known as a seodae in Korean) from the family of Princess Deokon's descendants housed in the National Hangeul Museum underwent emergency treatment for a special exhibition in 2019 upon the request of the National Hangeul Museum. Priority was given to the restoration of the original form of the severely damaged belt and the repair of its detached horn ornaments. Prior to the conservation treatment, researchers conducted a theoretical study of the belt with rhinoceros-horn adornments to learn the names of its structural components and the changes in form that the type experienced by period, thereby establishing a plan for conservation treatment and setting a direction. Among the belts worn by officials from the Joseon dynasty, rhinoceros-horn ornaments were attached to those of officials of the first rank and were considered the most precious behind the king's belt with its jade ornaments. The rhinoceros horn adorning the belt is classified into three categories according to quality. This belt has horn adornments of the highest quality, falling under the "grape design" category with dark brown dots concentrated in the center. The belt has a rectangular shape and lacks a buckle, reflecting a popular form from the nineteenth century. The structure of the belt was identified over the process of conservation treatment, offering information about its method of production. In addition, comparison of the relic with belts with rhinoceros-horn ornaments depicted in Joseon-period portraits of officials allowed the identification of changes in formal features and the detailed structures of belts with rhinoceros-horn ornaments by period. It confirmed that the belt subject to conservation treatment shows the features of belts with rhinoceros-horn ornaments produced in the nineteenth and twentieth centuries.

• Journal of Korean Society of Forest Science
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• v.111 no.1
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• pp.81-99
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• 2022

The Baekdudaegan, spanning around 701 km from Hyangrobong to Cheonwangbong of Mt. Jirisan in South Korea, is rich in biodiversity and known as the main ecological axis of the Korean Peninsula. The Neuljae-Yuksimnyeong section of Marugeum in the southern part of the Baekdudaegan, particularly Mt. Deogyusan, is an area in which various types of vegetation appear depending on the environmental characteristics. The aims of this study were to investigate the current vegetation status at the Neuljae-Yuksimnyeong section of the Baekdudaegan and to provide basic data to aid systematic conservation and management through future classification of forest vegetation types. A vegetation survey was conducted using 637 plots from May to October 2019. Vegetation-type analysis showed that the vegetation units could be classified as a Quercus mongolica community group divided into seven communities: the Abies koreana community, Sanguisorba hakusanensis community, Persicaria hydropiper community, Quercus variabilis community, Quercus dentata community, Cornus controversa community, and Quercus mongolica community. The A. koreana community was subdivided into the Dryopteris expansa group and Picea jezoensis group. The Q. variabilis community was also subdivided into the Q. dentata group and Q. variabilis typical group. We concluded that special management plans for distinctive forest vegetation, including subalpine vegetation, grass or herb vegetation, and agricultural vegetation, should be prepared urgently to aid ecosystem preservation and enhancement.

• Conservation Science in Museum
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• v.27
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• pp.125-146
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• 2022

The Wooden Gamsil with Inscription of "Botajeon" in the collection of the Dongguk University Museum was made in imitation of the wooden architecture style of the late Joseon period. The Gamsil had suffered exfoliation in the pigment and loss of components and thus underwent conservation treatment. Prior to the conservation treatment, the damage was classified by type and form, scientific analysis was carried out on the fiber and the species of wood, and portable X-ray fluorescence (P-XRF) analysis was conducted for the pigment component analysis. According to the analyses, Korea Pine(Soft pine) was used for most parts of the Gamsil, Manchurian walnut (Jugalns spp.) was used for the signboard, and the fiber used was identified as rice straw (Oryza sativa). The P-XRF identified white lead and zinc oxide in the white pigment, red lead in the red pigment, ultramarine blue in the blue pigment, and emerald green in the green pigment. For the conservation treatment, contaminants attached to the gamsil were removed by both dry and wet cleaning, detached parts were reattached in their original places, and lost parts were restored.

• Journal of Soil and Groundwater Environment
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• v.27 no.spc
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• pp.99-112
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• 2022

From early 2000, many researchers in the groundwater and soil environment remediation project tried to calculate the pollution level and pollution remediation cost and reflect it in the design. In addition, by identifying the movement characteristics of oil pollutants in the underground environment, many researchers tried to derive design factors necessary for pollution purification. However, although the test should be conducted in an area contaminated with oil, the toxicity and risk are too great for testing by deliberately leaking pollutants that are harmful to the human body. And as oil-contaminated areas are promoted by military units such as returned US military bases, there is a limit to access by the general public. In addition, since the indoor simulation test and the field application test have been carried out separately from each other, it was difficult to compare and review various simulation tests Therefore, in this study, PITT (Partitioning Interwell Tracer Test) and analysis methods were specifically presented through actual tests so that field workers could easily use them with the help of the military base and the Korea Rural Community Corporation Soil Environment Restoration Team. However, in order to directly reflect the distribution tracer test results in the pollution remediation design, it is necessary to reduce the analysis errors by comparing the analysis results of the existing soil pollution survey, physical exploration, and numerical modeling. In addition, it is judged to be cautious in the analysis because errors can easily occur due to various factors such as the type of oil at the polluted site, the hydraulic conductivity of the aquifer, and the skill of the researcher.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.40 no.4
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• pp.49-57
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• 2022

This study was conducted with the aim of investigating the garden architectural characteristics of Villa d'Este, which occupies a major role in the exploration of the contrasting background, location, and spatial composition characteristics of Italian Renaissance gardens. The survey for the study was divided into a literature survey and a field survey, and the details are as follows. First, in the mid-to-late 16th century, the villa was built under the direction of Cardinal Ippolito d'Este, and afterwards, the ownership of the villa was restored to the Italian government in 1850 due to financial difficulties. The Villa d'Este, which suffered another damage, is now operated with many visitors after going through the restoration process. Second, in the case of location, it has the characteristics of Urbana located in the city center and has valley-type topographical conditions located at the foot of the mountain.Third, in the case of spatial composition, it is orthogonal to the axis, and each part of the garden is developed, influenced by the contrast principles such as the installation of the Cortile del Belvedere and Villa Madama in the early 16th century. The main building is located in the hills so that you can see the garden and the surrounding scenery at a glance. Fourth, among the components, there were stairs, logia, courtyard, and grotto, fountains, cascades, ponds, and vegetation such as laurels, thorn trees.