• Proceedings of the Korean Institute of Building Construction Conference
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• 2019.11a
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• pp.66-67
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• 2019

Insulated buildings are exposed to the external environment due to aging and construction problems, resulting in a decrease in building energy efficiency. Therefore, the purpose of this paper is to provide a material for the change in thermal conductivity of the insulation when it is exposed to various external environments. In the experiment, five types of heat insulating materials were selected, stored under different environmental conditions, and the thermal conductivity was measured periodically to confirm the change in thermal conductivity. As a result, the thermal conductivity of all the insulating materials except the PF board increased with the passage of time. This is because thermal insulation absorbs atmospheric moisture under all environmental conditions and the thermal conductivity increases, and in the case of thermal insulation stored indoors in environmental conditions, the temperature differs from the thermal insulation stored outside. It is considered that there is little evaporation of moisture absorbed constantly, and the change in thermal conductivity is large.

• Journal of Digital Convergence
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• v.19 no.3
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• pp.353-361
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• 2021

As demands for health and wellbeing in the ageing society have grown, complex problems involving diverse stakeholders arise in the healthcare environment. The objective of this study is to identify roles and abilities of designers in a healthcare setting where professionals from different disciplines collaborate to achieve a common goal. Case studies on healthcare design projects adapting interdisciplinary approach were explored to find which methods and processes were implemented effectively. Results are based on three research questions that lead to analyzing multifaceted roles of designers regarding process facilitation, manage relations, visualization, and imagination.

• Journal of the Korean Society for Precision Engineering
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• v.12 no.8
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• pp.147-155
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• 1995

Recent experimental studies have been shown that strain gages can be employed to determine either static or dynamic stress intensity factors $K_{I}$ wiht relatively simple experiments. However, it does not usually provide a reliable value of stress intensity factor because of local yielding and limited regions for strain gage placement at the vicinity of the crack tip. This paper attempted to define a valid region and to indicate procedures for locating and orienting the strain gage to determine static toughness $K_{Is}$ accurately form one strain gage readings with respect to varying loadings. The strain gage methods was used for compact tension specimens made of Polycarbonate and PMMA(polymethyl methacrylate). Series expansions of the static and dynamic strain fields are applied. Strain gage orientation and location are then studied to optimize the strain response. Especially, in the dynamic experiment, the specimen employed is an oversized Charpy V-notch specimen which has been modified to provide significant constraint with a large elevation of the flow stress. The impact behavior of the specimen is monitored by placing strain gage near the crack tip. The dynamic toughness $K_{Id}$ is determined from the strain time traces of this gage.e.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2020.06a
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• pp.75-76
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• 2020

Use fire resistant construction methods, of which fire resistant boards are used to protect buildings and structures from fire. However, in the case of fire resistant boards, the unit price of the main raw material is high and the cost efficiency is low. There have been studies to apply oyster shells to fire resistant boards to solve these problems. On the other hand, egg shells are also considered to be applicable to fire-resistant boards with components like oyster shells, but there is no case of using egg shells as building materials. Therefore, in this study, we confirmed the physical properties of egg shell powers used as mortar filler and compared them with the fire resistant board flexural strength standard. As a result, it was judged that the powder of egg shells could be used as a building material, because the standards for the flexural strength of fire resistant boards were satisfied except for a part.

• Journal of the Semiconductor & Display Technology
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• v.22 no.2
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• pp.6-10
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• 2023

High-potential data can be predicted and stored in the cache to prevent cache misses, thus reducing the processor's request and wait times. As a result, the processor can work non-stop, hiding memory latency. By utilizing the temporal/spatial locality of memory access, the prefetcher introduced to improve the performance of these computers predicts the following memory address will be accessed. We propose a prefetcher that applies the GRU model, which is advantageous for handling time series data. Display the currently accessed address in binary and use it as training data to train the Gated Recurrent Unit model based on the difference (delta) between consecutive memory accesses. Finally, using a GRU model with learned memory access patterns, the proposed data prefetcher predicts the memory address to be accessed next. We have compared the model with the multi-layer perceptron, but our prefetcher showed better results than the Multi-Layer Perceptron.

• Imaging Science in Dentistry
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• v.37 no.4
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• pp.185-189
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• 2007

Purpose: This study was intended to estimate the prevalence of cemento-osseous dysplasia (COD) in the Korean population and to assess the clinical and radiographic characteristics of this condition. Materials and Methods: Panoramic radiographs from 10,646 patients (4,982 males and 5,664 females, age range from 6 to 91 years) were reviewed for evidence of COD. Their demographics, clinical characteristics, and radiographic features were retrospectively assessed. Results: Of 10,646 panoramic radiographs, 33 radiographs (0.31 %) exhibited evidence of COD. The prevalence of COD increased to over 1 % in women over 40-years old. Of these 33 patients, 16 had florid cemento-osseous dysplasia (FCOD) and 17 had focal COD. Due to the multiplicity of FCOD, a total of 63 COD lesions were assessed. These lesions were most common in the mandibular molar area. Most of the COD lesions examined (61.9%) were less than 10 mm and the majority (82.5%) showed radiopacity. Conclusion : COD has a predilection for the mandibular molar area of middle-aged and older women.

• Imaging Science in Dentistry
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• v.37 no.4
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• pp.217-220
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• 2007

Purpose: The purpose of this study was to compare the location of the mandibular canal in Class III malocclusion to its location in normal occlusion for adults. Materials and Methods: For this study 32 skeletal Class III patients and 26 normal patients were observed. Four measurements were taken on cross sectional tomography between the first and second molars: the distance from the mandibular canal to the inner surface of both the buccal and lingual cortices, the distance from the mandibular canal to the inferior border of the mandible, and the buccolingual width of the mandible. The buccolingual location of the canals was classified as lingual, central, or buccal. Each measurement was analyzed with an independent t test to compare Class III malocclusion to normal occlusion. Results: Compared to the control group, the prognathic group had a shorter distance from the canal to the inner surface of the lingual cortex and to the base of the mandible. A higher percentage of the canals were located lingually in the prognathic group. Conclusion: This study showed that the mandibular canal was located more lingually and inferiorly in prognathic patients than in patients with normal occlusion. These results could help surgeons to reduce injuries to the inferior alveolar nerve.

• Food Science and Biotechnology
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• v.17 no.1
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• pp.156-160
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• 2008

This study was conducted to evaluate the hypotensive properties of the extract of Chinese balloon flower (Platycodon grandiflorum)'s root. In the studies for calcium channel-blocking using Xenopus oocytes, the ethanol-extract ($26.2{\pm}5.2%$) showed higher activity than water-extract. Twenty female rats were fed 25, 35, and 45 mg/kg BW/day of the ethanol-extract for 14 days to observe the changes in blood pressures and heart pulses. Ethanol-extract decreased the systolic, diastolic, and mean blood pressures of the rats. Especially, the rats fed with 45 mg/kg BW/day of the ethanol-extract showed significant decreases in the blood pressures. These results suggested that a decrease in blood pressures was due to the extension of a blood vessel with calcium channel-blocking by ethanol-extract of Chinese balloon flower. Forty %-ethanol showed the highest efficiency for ethanol-extraction of Chinese balloon flower.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.22 no.1
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• pp.137-144
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• 1992

This study was performed to observe the effects of arthrography on the tissues of temporomandibular joint histopathologically. Among 17 rabbits (34 joints), 2 (4 joints) were used as normal control group, others (30 joints) were experimentally arthrographed using 0.03㎖ diatrizoate meglumine (Hypaque meglumine 60, Wintrop, U.S.A). The rabbits were sacrificed at 2-hour, 1-, 2-, 4- and 7-day after experiment and the tissues of temporomandibular joint were prepared according to the usual method for light microscopic examination. The results were as follows: 1. There were no changes of the fibrous connective tissues of the condylar fossa, the fibrous connective tissues and hyaline cartilages of the condyle, and the articular dislc 2. In 2-hour experimental group, the proliferation of the surface synovial membrane cells, the congestion and hemorrage of the vessels were observed. 3. In 1 and 2-day experimental group, minimal lymphocytes infiltration was observed with the proliferation of the surface synovial membrane cells, the congestion and hemorrage of the vessels. 4. In 4-day experimental group, the diminution of the proliferation of the surface synovial membrane cells was seen, but there was no vascular changes. 5. In 7-day experimental group, the tissues showed similar appearance to the normal control group.

• Proceedings of the Ginseng society Conference
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• 2006.05a
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• pp.77-77
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• 2006