• Journal of the Korean Society of Environmental Restoration Technology
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• v.7 no.4
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• pp.8-16
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• 2004

The industrialization of central Europe more than 100 ago marked the beginning of densely concentrated buildings in quickly growing cities. A cheap type of roofing material of that time was tar. But it was dangerous because it was high inflammable. Then some roofer had a splendid idea. They used sandy material as a final layer atop the impermeable tar layer. These roofs were much more fire resistant than the typical roofs. In this sandy layer some plant species began to grow spontaneously. This was the beginning of the green roof history of modern Europe. A number of these green roofs survived both world wars. In the early 80's in Berlin alone, 50 such buildings existed and they continued to be waterproof until the present day. Since the 1992 Earth Summit of 1992 in Rio de Janeiro(http://www.johannesburgsummit.org/html/basic_info/unced.html) the term "sustainable development" became of central interest of urban designers. In city regions green roofs had become synonymous with this term. With a small investment, long-lasting roofs can be created. Further back in history, more exciting examples of green roofs can be found. The hanging gardens of antiquity are well-known. There are also green roofs built as insulation against cold and heat all over the world. For over 20 years, roof greening in central Europe has been closely examined for various reasons. Roof greening touches several different disciplines. Of primary interest is the durability of the roofs. But ecologists are also interested in green roofs, for instance in biodiversity research. The beneficial effect of greening on water proofing was also proven. For some time, the issue of fire protection was investigated. According to tests, green roofs received a harsh careful rating. Their fire protective property is considered similar to that of tile roofs. Another recent impulse for the green roof movement in Germany has come from the evident improvement of storm water retention and the reduced burden on the sewer system. The question of whether and how much energy green roofs can save has become an urgent question. The state of the research and also various open questions from a central European point of view will be discussed in the context of international collaboration. Apart from academic considerations, those who involve themselves in this issue take a predominantly positive view of the numerous existing green roofs in Germany. In some cities, green roofs are the typical construction technique for new buildings. A few outstanding examples will conclude this review. In Germany, about 20 companies, some of which operate internationally, specialize in green roof consulting. Learning from each other in an open-ended way with respect to different construction techniques and applications in various climatic regions can only be accomplished through such international collaboration as is taking place here.

• Journal of the Korea institute for structural maintenance and inspection
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• v.25 no.5
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• pp.114-126
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• 2021

This paper compared bridge maintenance in United Stated, United Kingdom, Japan, and Korea. Bridges play an essential role in transportation network and in the economic production process. To provide a desirable level of service to the public within limited budgets, it is required to provide effective bridge maintenance activities (e.g. inspection and repair/rehabilitation) at acceptable level of bridge service. A number of bridges are expected to age rapidly in Korea, which will be the excess burden of government. Since several countries have experienced a number of deteriorated bridges because of aging, the countries aforementioned in this study have already developed comprehensive bridge maintenance programs such as inspection practice and repair/rehabilitation techniques. Therefore, the goal of this paper is to synthesize and to compare useful knowledge on bridge maintenance and bridge crack repair/restoration of deteriorated concrete bridge in the four countries. Finally, recommendations that will serve as guidance to transportation agencies for potential enhancements to bridge maintenance and bridge repairs are presented.

• Korean Journal of Heritage: History & Science
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• v.48 no.1
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• pp.44-61
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• 2015

The research on the conservation of the movable modern and contemporary cultural heritage have been actively performed internationally since late 20th century. In this study, the international research trends of movable modern and contemporary cultural heritage conservation in last decades were analyzed. Setting up the range of the period, research papers were collected through various databases based on the systematic literature review process. Samples of 45 domestic papers and 505 foreign papers were classified by materials as books and paper, metals, textiles and fibers, photographs and audio-visuals, woods, plastics and ceramics and glass. The types of treated artifacts, detailed materials of the treated artifacts, and the research subjects were investigated from each paper. The data were compiled statistically and analyzed. Number of papers are published domestically in the book and paper conservation and metals conservation fields, but there are needs for more diversified artifact types and extensive research subjects. The researches in foreign countries are active in conservation of organic materials such as paper, textile and photographs and deal with various research subjects on not only treatment techniques and elemental analysis but also preventive conservation and conservation ethics. It is expected that this study would contribute to the field as a preliminary data on the conservation of modern and contemporary cultural heritage.

• Korean Journal of Heritage: History & Science
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• v.56 no.2
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• pp.124-133
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• 2023

Preservation processing for two combat boots was executed through application of 3-dimensional digital technology and with use of preservation materials providing outstanding reversibility and stability. The aim of this was to establish a method to preserve the relics of fallen Korean War soldiers that had been excavated by the soldiers remains excavation corps of the Ministry of National Defense. It was possible to estimate the foot size of the soldiers who would have worn the combat boots via 3-dimensional digital scanning and modeling of the boots. In this process, the original form of the combat boots was restored through the use of 3D-printed structures. The original form was restored through a process of removing contaminants from the excavated relics and performing a conditioning treatment, and through use of an antique-color treatment after bonding and filling in the sections that had been ripped or deteriorated. Following the aforementioned preservation processes, it was possible to confirm that both of the combat boots had soles and top sections made of rubber, and portions of the top section and ankle section of the boots were made of synthetic rubber. As such, it was confirmed that these were similar to the Shoe Pac(M-1944, 12-inch) winter boots that had been manufactured for the purposes of waterproofing and/or protection against cold, and introduced in 1944. Such results confirmed that it is possible to discover the manufacturing techniques, materials, and uses of relics excavated through application of preservation processing, thereby illustrating the importance of the convergent research of scientific preservation processing and 3-dimensional digital technology.

• The Journal of Korean Academy of Prosthodontics
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• v.61 no.4
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• pp.316-327
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• 2023

In the case of fully edentulous patients with severe alveolar bone resorption, the consideration of 'All-on-X' implant-supported fixed prosthesis after placing four or more implants in the anterior maxilla is possible. Recent advancements in digital dentistry have enabled systematic and predictable treatment in all phases, including diagnosis, surgery, and prosthesis fabrication. By incorporating digital dentistry techniques such as digital complete denture, implant surgical guides, facial scanning into the conventional restoration process, it is possible to reduce the complexity of the prosthesis fabrication and effectively achieve the transition from provisional prosthesis to definitive prosthesis in terms of both aesthetics and function.

• Korean Journal of Heritage: History & Science
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• v.55 no.2
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• pp.200-211
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• 2022

The celadon stools with an openwork ring design which consist of four items as one collection were excavated from Gaeseong, Gyeonggi-do Province. The celadon stools were designated and managed as treasures due to their high arthistorical value in the form of demonstrating the excellence of celadon manufacturing techniques and the fanciful lifestyles during the Goryeo Dynasty. However, one of the items, which appeared to have been repaired and restored in the past, suffered a decline in aesthetic value due to the aging of the treatment materials and the lack of skill on the part of the conservator, raising the need for re-treatment as a result of structural instability. An examination of the conservation condition prior to conservation treatment found structural vulnerabilities because physical damage had been artificially inflicted throughout the area that was rendered defective at the time of manufacturing. The bonded surfaces for the cracked areas and detached fragments did not fit, and these areas and fragments had deteriorated because the adhesive trickled down onto the celadon surface or secondary contaminants, such as dust, were on the adhesive surface. The study identified the position, scope, and conditions of the bonded areas at the cracks UV rays and microscopy in order to investigate the condition of repair and restoration. By conducting Fourier-transform infrared spectroscopy(FT-IR) and portable x-ray fluorescence spectroscopy on the materials used for the former conservation treatment, the study confirmed the use of cellulose resins and epoxy resins as adhesives. Furthermore, the analysis revealed the addition of gypsum(CaSO₄·2H₂O) and bone meal(Ca₁₀ (PO₄)₆(OH)₂) to the adhesive to increase the bonding strength of some of the bonded areas that sustained force. Based on the results of the investigation, the conservation treatment for the artifact would focus on completely dismantling the existing bonded areas and then consolidating vulnerable areas through bonding and restoration. After removing and dismantling the prior adhesive used, the celadon stool was separated into 6 large fragments including the top and bottom, the curved legs, and some of the ring design. After dismantling, the remaining adhesive and contaminants were chemically and physically removed, and a steam cleaner was used to clean the fractured surfaces to increase the bonding efficacy of the re-bonding. The bonding of the artifact involved applying the adhesive differently depending on the bonding area and size. The cyanoacrylate resin Loctite 401 was used on the bonding area that held the positions of the fragments, while the acrylic resin Paraloid B-72 20%(in xylene) was treated on cross sections for reversibility in the areas that provided structural stability before bonding the fragments using the epoxy resin Epo-tek 301-2. For areas that would sustain force, as in the top and bottom, kaolin was added to Epo-tek 301-2 in order to reinforce the bonding strength. For the missing parts of the ring design where a continuous pattern could be assumed, a frame was made using SN-sheets, and the ring design was then modeled and restored by connecting the damaged cross section with Wood epos. Other restoration areas that occurred during bonding were treated by being filled with Wood epos for aesthetic and structural stabilization. Restored and filled areas were color-matched to avoid the feeling of disharmony from differences of texture in case of exhibitions in the future. The investigation and treatment process involving a variety of scientific technology was systematically documented so as to be utilized as basic data for the conservation and maintenance.

• Journal of Korea Multimedia Society
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• v.16 no.2
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• pp.206-212
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• 2013

Information and Communications Technologies(ICT) represented by Multimedia, Virtual Reality and Network could be used as the better ways to preserve and restore the original shape of cultural contents. This paper presents the detailed methods of Multimedia and Virtual Reality technologies to digitally implement the traditional wooden buildings which are called as a typical 'Korean Cultural Content." We implemented a 3D modeling of architectural parts, realized a roof curve, and texture-mapped the material qualities of traditional wooden buildings by using Graphic techniques. In addition, the information, which is implemented by marker-based Augment Reality, for the traditional wooden buildings can be obtained through the mobile appliances such as a smart phone. We, also, presented how to practically use the implemented digital Korea traditional wooden buildings.

• Journal of the korean academy of Pediatric Dentistry
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• v.43 no.4
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• pp.461-466
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• 2016

Dental caries is an important dental disease among children and adolescents that can continue for a lifetime. Early detection of dental caries in deciduous dentition is significant because it can influence the permanent teeth. It is also critical to prevent dental caries by performing fluoride treatment and pit-and-fissure sealant for high-risk children. Various methods have been developed for the early detection of dental caries; however, many studies are still seeking to discover more effective methods. In general, visual examination and radiographic images are used, but these techniques have several limitations such as errors and radiation exposure. In this study, clinical application of the newly developed DIAGNOcam caries identification device and its possible applications were examined. DIAGNOcam was applied to diagnose dental caries in the posterior teeth of patients in the Department of Pediatric Dentistry, and it was confirmed that it could be used to detect proximal caries, the margin of restoration, and the extent of dental caries lesions.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.35 no.6
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• pp.442-450
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• 2009

Purpose: Simultaneous implantation has been traditionally limited to patients with at least 5 mm of residual bone to ensure that the implant is completely stabilized. This is considered to be one of the most critical factors for primary implant stability and parallelism and, subsequently osseointegration. Recently, improved initial implant stability is provided by advancement of surgical techniques, implant designs and surface treatments. This has led surgeons to extending simultaneous treatment option to patients with below 4 mm of residual bone height, despite the lack of much data. The purpose of this study was to retrospectively evaluate and compare the status of implants which are installed by delayed and simultaneous methods. Material and methods: The subjects were patients(121 patients, 278 implants) who had been operated with sinus lifting from 2003 to 2007 in Sun Dental Hospital. Lateral window approach with autograft and xenograft(1:1 ratio) were carried out for all sinus lifting. 4 types of implant were used. The mean follow up period was 26.3 months(19 - 58 months) in delayed group, and 22.8 months(18 - 43 months) in simultaneous group. Results: The survival rate of implant restoration of this study was 98.2% in delayed group and 91.7% in simultaneous group. In simultaneous group, wide-platform type implants showed 100% survival rate. The total average of marginal bone loss in radiographs was $0.96\;{\pm}\;0.29\;mm$ in delayed group and $1.02\;{\pm}\;0.31\;mm$ in simultaneous group. Conclusion: Simultaneous implantation with sinus lifting(below 4mm of residual bone height) could be predictable treatment.

• The Journal of Korean Academy of Prosthodontics
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• v.39 no.2
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• pp.197-207
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• 2001

Development of new ceramics and esthetic needs of patients increase the use of all ceramic restorations. Fractured teeth often need metal post and core as foundation for final restoration. When all ceramic restorations are planned, metal post and core may lead to compromised esthetics because of opacity and gray color of metal post and core. Many techniques have been proposed to solve this problem such as application of an opaque porcelain to the metal core or all ceramic post and core. This study was performed to evaluate effect on color of Empress 2 crown according to various post systems. Color was evaluated by the CIE $L^*a^*b^*$ systems and measured by spectrophotometer (Model CM-3500, Minolta, Japan). Specimens were divided into 4 groups as follows Group 1 : gold cast post specimen + Empress 2 crown specimen Group 2 : application of an opaque porcelain to gold cast post specimen + Empress 2 crown specimen Group 3 : cosmopost specimen + Empress 2 crown specimen Group 4 : In-ceram post specimen + Empress 2 crown specimen. The results obtained as follows, 1. $L^*$ Values showed that group 2, 3, 4 were higher than group 1 with significant difference and group 2, 3, 4 were not significantly different. 2. $a^*$ Values and $b^*$ values also showed that group 2. 3, 4 were higher than group 1 with significant difference and group 2, 3, 4 were not significantly different. 3. ${\Delta}E^* ab$ Values showed that ${\Delta}E^* ab$ 3 was the highest value and ${\Delta}E^* ab$ 5 was the lowest value.