• Journal of the Korea Institute of Building Construction
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• v.16 no.2
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• pp.97-105
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• 2016

Recently, application case of the ultra rapid hardening concrete-polymer composite(URHCPC) are increasing to repair for the deterioration of pavement. But it is a major disadvantage that the main material is expensive and has environmental load. For these reasons, the development of the economic, eco-friendly materials is needed. Calcium Aluminate Composite (CAC), produced by rapid cooling of atomizing method with molten ladle furnace slag, is a material capable of improving the economic feasibility and reducing the environmental load of URHCPC. In this paper, the properties of CAC and gypsum mixed CAC (GC) as alternative materials of RSC according to the types of polymer dispersion were studied. The results were as follows; compressive strength, tensile strength, flexural strength, bonding strength and modulus of elasticity of the composites using CAC or GC showed higher values than those of plain proportion in 3 hour. In later age, they were at the same level as the general proportions. URHCPC using BPD as polymer dispersion had superior strength properties generally. But modulus of elasticity was the same level as the case of using a SBR latex. According to these results, CAC or GC can partially substituted for RSC to product the URHCPC. When URHCPC uses the BPD as the polymer dispersion, it can be improved performance.

• Journal of the Korean Recycled Construction Resources Institute
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• v.7 no.4
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• pp.323-332
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• 2019

Non-curable rubberized polymer asphalt waterproof coating materials in Korea and China are manufactured without advanced quality control techniques and common standard, And they are exposed consistent water leakage problems. Import and application of Korean waterproofing products and installation methods is difficult in the present situation as the Chinese standard(JC/T 2428) is different in nature with the Korean counterpart products, And quality assurance is inevitable based on mutual standards. In order to resolve this issue, alternatives such as using standards provided by the ISO (International Organization for Standardization) are generally employed, but there is no such ISO standard as a waterproof material for non-curable rubberized polymer asphalt material. Furthermore, it is unreasonable to develop the ISO standard for rubber asphalt seals for exchange in terms of time and cost. This study proposes that the establishment of a quality standard that can be applied for both countries will be required via an joint international standard that outlines the properties of materials if applied in mutual trade exchange.

• Journal of Auto-vehicle Safety Association
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• v.10 no.4
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• pp.7-12
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• 2018

Injury mechanisms of lower extremity injuries in motor vehicle accidents are focused on fractures, sprains, and contusions. The purpose of this study is to evaluate the analysis of lower extremity injury mechanism in occupant motor vehicle accident by using Hospital Information System (HIS) and reconstruction program, based on the materials related to motor vehicle accidents. Among patients who visited the emergency department of Wonju Severance Christian Hospital due to motor vehicle accidents from August 2012 to February 2014, we collected data on patients with agreement for taking the damaged vehicle's photos. After obtaining the verbal consent from the patient, we asked about the cause of the accident, information on vehicle involved in the accident, and the location of car repair shop. The photos of the damaged vehicle were taken on the basis of front, rear, left side and right side. Damage to the vehicle was presented using the CDC code by analytical study of photo-images of the damaged vehicle, and a trauma score was used for medical examination of the severity of the patient's injury. Among the 1,699 patients due to motor vehicle crashes, 88 (5.2%) received a diagnosis of lower extremity fracture and 141 (8.3%) were the severe who had ISS over 15. Nevertheless during 19 months for research, it was difficult to build up in-depth database about motor vehicle crashes. It has a limitation on collecting data because not only the system for constructing database about motor vehicle crash is not organized but also the process for demanding materials is not available due to prevention of personal information. For accurate analysis of the relationship between occupant injury and vehicle damage in motor vehicle crashes, build-up of an in-depth database through carrying out various policies for motor vehicle crashes is necessary for sure.

• Korean Journal of Heritage: History & Science
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• v.43 no.3
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• pp.4-25
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• 2010

This study was carried out on scientific conservation treatment based on material characteristics, provenance interpretation, and deterioration diagnosis for seven-storied Jungwon Tappyeongri stone pagoda in Chungju. As a result, main rock of the pagoda is biotite granite with magnetite-series (average $5.86{\times}10^{-3}$ SI unit), containing partly basic xenolith, pegmatite veinlet and feldspar phenocryst. As a result of the provenance presumption of the host rock, a rock around the Songgang stream was identified the same origin. Therefore the rock is appropriate for materials of the pagoda restoration. The deterioration assessment suggested that the pagoda was seriously exfoliated (2.7 to 5.5%), discolored (39.8 to 58.9), and contaminated with repair materials (3.5 to 9.4%), and bioorganisms (19.3 to 24.4%). Accordingly, conservation treatment was carried out based on preliminary investigation for stable conservation of the pagoda. Overall processes were sequentially proceeded by restoration of the replacement stone, cleaning, joining and consolidation. This study sets up an integrated conservation system from preliminary investigation to conservation treatment of the pagoda. Also, the study will contribute for establishing the future-oriented customized conservation treatment.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.22 no.3
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• pp.55-71
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• 2019

The purpose of this study is to propose an evaluation method to assess green environments of streetscapes to improve urban street green spaces in Jeonju City. Through a rapid assessment of urban street green spaces, we suggest an objective basis for expanding street green space as well as for adopting sustainable maintenance and improvement measures. We choose 12 sections of streetscapes (roads and sidewalks) to investigate existing street conditions which have more than four lanes and function as major road axes. Six large roads and six medium roads of Jeonju City center area are investigated as pilot assessment study sites. Site inventory checklists consist of environmental characteristics of streetscape, street tree status, and planting condition evaluation. Environmental characteristics of streetscapes are composed of physical and neighborhood factors. For instance, items for physical factors are types and width of road/sidewalks, paving materials, tree protection materials, and green strip. And surrounding landuse is a neighborhood factor. Assessment items for street tree status are street plant names (tree/shrubs/ground cover), size, and planting intervals. Planting condition evaluation items are tree shape, damage, canopy density, and planting types with existence of adjacent green space. Evaluation results are classified into three levels such as A(maintain or repair), B(greening enhancement), and C(structural improvement). In case of grade A, streetscapes have enough sidewalk width for maintaining green strip and a multi-layered planting(in large road only) with fairly good growing conditions of street trees. For grade B and C, streetscapes have a moderate level of sidewalk width with a single street tree planting. In addition, street tree growing conditions are appeared poor so that green enhancement or maintenance measures are needed. For median, only grade B and C are found as its planting growing foundations are very limited in space. As a result, acquiring enough sidewalk space is essential to enhance ecological quality of urban street green. Especially, it is necessary to have green strip with reasonable widths for plant growing conditions in sidewalks. In addition, we need to consider native species with multi-layer plant compositions while designing street green.

• Journal of radiological science and technology
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• v.44 no.4
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• pp.359-365
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• 2021

A heavy particle accelerator is a device that accelerates particles using high energy and is used in various fields such as medical and industrial fields as well as research. However, secondary neutrons and particle fragments are generated by the high-energy particle beam, and among them, the neutrons do not have an electric charge and directly interact with the nucleus to cause radiation of the material. Quantitative evaluation of the radioactive material produced in this way is necessary, but there are many difficulties in actual measurement during or after operation. Therefore, this study compared and evaluated the generated radioactive material in the concrete shield for protons and carbon ions of specific energy by using the simulation code FLUKA. For the evaluation of each energy of proton beam and carbon ion, the reliability of the source term was secured within 2% of the relative error with the data of the NASA Space Radiation Laboratory(NSRL), which is an internationally standardized data. In the evaluation, carbon ions exhibited higher neutron flux than protons. Afterwards, in the evaluation of radioactive materials under actual operating conditions for disposal, a large amount of short-lived beta-decay nuclides occurred immediately after the operation was terminated, and in the case of protons with a high beam speed, more radioactive products were generated than carbon ions. At this time, radionuclides of ⁴⁴Sc, ³H and ²²Na were observed at a high rate. In addition, as the cooling time elapsed, the ratio of long-lived nuclides increased. For nonparticulate radionuclides, ³H, ²²Na, and for particulate radionuclides, ⁴⁴Ti, ⁵⁵Fe, ⁶⁰Co, ¹⁵²Eu, and ¹⁵⁴Eu nuclides showed a high ratio. In this study, it is judged that it is possible to use the particle accelerator as basic data for facility maintenance, repair and dismantling through the prediction of radioactive materials in concrete according to the cooling time after operation and termination of operation.

• Conservation Science in Museum
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• v.26
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• pp.83-182
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• 2021

This study summarized the results of the conservation treatment and investigation on the production method of the golden crown (Treasure No. 339) excavated from Tomb No. 129 (also known as Seobongchong Tomb) in Noseo-dong, Gyeongju-si, Gyeongsangbuk-do Province. The golden crown from Seobongchong Tomb was discovered during the excavations conducted by the Museum of the Government-General of Korea in 1926 during the Japanese colonial era. It is currently in the collection of the National Museum of Korea. A total of six Silla golden crowns have survived in Korea, among which the crown from Seobongchong Tomb is the only example with a dome-shaped hemispherical decoration attached with a bird ornament while otherwise showing the typical features of Silla crowns. The crown had been repaired following its excavation using metallic materials and adhesives, but due to the partial deformation and damage brought about by the repair materials, it required further conservation treatment. This article describes in detail the overall process of the conservation treatment and the restoration of the original form of the golden crown from Seobongchong Tomb, particularly the method of reinforcing the joints to secure the stability of the crown. It presents the characteristics of the crown's production as revealed in the investigation during the conservation treatment, and further analyzes the relationship of this crown from Seobongchong Tomb with other Silla crowns through a comparison of their production techniques. The investigation revealed that the crown was primarily decorated with golden sequins at the time of its production. At a later point some of the sequins in the upright ornament were replaced with comma-shaped jade beads and additional comma-shaped jade beads were added to the headband. In order to determine if such modifications to the decoration had occurred with other Silla crowns, the decoration of the six extant Silla golden crowns were investigated. The crown from Cheonmachong Tomb features traces of this same modification to the decoration and possesses other similarities with the crown from Seobongchong Tomb.

• Journal of the Korea Society of Computer and Information
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• v.14 no.8
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• pp.145-152
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• 2009

Manufacturer's competitiveness in the MRO industry, which is to stimulate the growth of the business-to-business e-commerce market, has recently become more important. A nuclear parts manufacturer was supplying products based on irregular demand from clients which differs from ordinary MRO business practices. The reason for this is the Nuclear Parts Manufacturer has fallen behind the e-commerce performance of other industries, and they lack global competitiveness due to the low efficiency of the individual companies within it. In this study, we developed an MRO based a-Marketplace system to minimize repetitive ordering of raw materials, lack of reusability and inefficiency of transaction processing which was a result of the former legacy business practice, In order to accomplish the purpose of this study, we implemented a web based automated CR system which considered the characteristics of the nuclear parts manufacturing: the system has sub modules such as ordering, product management, transaction management, warehousing and raw material handling. As a consequence of the system implementation, H corporate successfully automated ordering of raw materials, quotation processing and inventory management compared to the legacy business process, achieving increased efficiency by reducing wasteful resources.

• Journal of Bio-Environment Control
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• v.23 no.2
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• pp.148-157
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• 2014

The purpose of this study was to investigate greenhouse maintenance by farms by looking into greenhouses across the nation for greenhouse specification, disaster-resistance greenhouse construction, types and degree of damage due to natural disasters, pre-inspection in case of typhoon or heavy snow forecast, and fire-fighting facilities to prevent a fire. The findings were summarized as follows: as for greenhouse specification, the highest proportion of them were 90 m or longer both in single- and multi-span greenhouses in terms of length; 8 m or wider and 7.0~7.9 m in single- and multi-span greenhouses, respectively, in terms of width; 1.5~1.9 m and 2.0~2.9 m in single-and multi-span greenhouses, respectively, in terms of height; and 3.0~3.9 m and 6 m in single- and multi-span greenhouses, respectively, in terms of diameter. As for disaster-resistance greenhouses, farmers were reluctant to install such greenhouses. The low distribution of disaster-resistance greenhouses was attributed to the greenhouses built dependent on the old practice, the greenhouses already completed, and relatively high construction costs. As for damage by natural disasters, greenhouses were subject to more damage by typhoons than heavy snow. They mainly inspected the ceiling and side windows, entrances, and fixation bands for covering materials in case of typhoon forecast and the heating devices in case of heavy snow forecast. As for repair methods for greenhouse pipe corrosion, they preferred partial replacement to painting and did not use stiffeners for structures to prevent a natural disaster in most cases. As for the maintenance of greenhouse covering materials, most farmers inspected their sealing property but did not clean the coverings for light transmission. The destruction of structural materials can be prevented by eliminating greenhouse covering materials during a typhoon, but they were not able to do so because of the covering material replacement costs and the crops they were growing. The study also examined whether greenhouse farms had fire-fighting facilities to prevent a fire and found that they lacked the perception of greenhouse fire prevention to a great degree.

• Journal of Veterinary Clinics
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• v.20 no.3
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• pp.294-301
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• 2003

This study was performed to compare the effects of hydrocolloid(Duoderm$\circledR$, HC in this study) and hydrogel (Nu-Gel$\circledR$, HG in this study) occlusive dressing materials on degree of exudate, wound contraction, epithelialization, and healing of full-thickness skin wound in dogs. Three wounds measuring 2${\times}$2 cm in size were created bilaterally(6 wounds/dog) on the dorsolateral aspect of the trunk of 12 dogs. In each dog, the wounds were treated with HC, HG, and normal saline, respectively. For a 4 week period, the wounds were evaluated gross aspects and histopathological aspects. There were no statistically significant differences between treatment groups in percentage of wound contraction, percentage of epithelialization, and percentage of wound total healing during the first week. Significant differences were first detected on day 14. On day l4(P < 0.01) and 21 (P < 0.05), mean percentage of epithelialization of HG-treated wound was significantly greater than those in HC- and normal saline-treated wound. Mean percentage of wound contraction of HG-treated wound was significantly greater than that in HC- and control wounds on day 21(P< 0.05). On day 21, mean percentage of wound healing of HG-treated wound was significantly greater than that in HC- and control wounds(P < 0.02). On day 1, 4, and 7 after wound creation, although severe infiltration of PMN (polymorphonuclear leukocyte) cells in HC- and control wounds were observed in the subcutis and moderate infiltration of PMN cells in HG-treated wound were observed in the subcutis, we did not detect significant differences. On day 14 after wounding creation, in the wounds treated with HG dressing, epithelial cells were found over the surface, and edema further decreased in the tissue under the wounds, and the granulation tissue was replaced with collagen fibers. On day 21 after wound creation, in HG-treated wound compared with other experimental material-treated wounds, regenerated epidermis covered most of the wound surface, and the granulation tissue was more replaced with collagen fibers than that on day 14. Overall results indicated that the use of hydrogel dressing materials(Nu-Gel$\circledR$) as hydrocolloid dressing (Duoderm$\circledR$) materials and normal saline treatment on full-thickness skin wounds in dogs increased the rate of healing at repair stage.