• Journal of the Architectural Institute of Korea Planning & Design
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• v.35 no.9
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• pp.131-142
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• 2019

The purpose of this study was to find out the characteristics of housing policies and apartment designs by comparison of supplying and remodeling apartments between France and Korea. The literature review was used in Korea cases and the literature review, site investigation, and expert interviews were used in France cases. At first, by reviewing the related literatures about the apartment developments and regenerations in France and Korea, twelve remodeling cases were represented respectively in Ile de France and Seoul. As a result, in housing policy, the Korean housing market had a shortage of low-priced houses related to biased apartment developments by private sector dependence. Consequently, the living in Korea generally required the high price in low quality houses. But in France, the housing policies were very successful in housing quantity, quality, and expense. It is involved in balances between the public housing supply and the activation of a private housing market based on the government support policy. Nevertheless, in the success of the apartment as a house type, apartments in France means the social elimination because of the supply method problems and the management failures of HLM institutions. However, in Korea, the apartment implies the successful life of the middle class population because of the competitive evolutions during 40 years as a market housing. Secondly, In the characteristics of remodeling, the remodeling in Korea was for property value improvements. It mainly executed to expand the size of a house by expansion of living space. However the remodeling in France was for social mixes and connections with the surrounding area. It mostly performed by various design methods such as vertical merging houses, partial removal, reconstruction, and construction of a local community centers and mixed-use residential buildings. This study shows the simultaneously remodeling features of those two countries. These findings can be used in developing effective strategies for the public housing regenerations in Korea and other countries.

• Korean Journal of Metals and Materials
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• v.46 no.3
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• pp.169-173
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• 2008

Characteristics of etching and induced surface morphology variation by wet-etching of n-type GaN were investigated using phosphoric acidic solutions. Generally, the etch-rate was increased as the temperature of the etch solutions was increased, and the highest etch rate of about $300{\AA}/min$ was achieved at the temperature of $180^{\circ}C$. The morphology variation of the etched surface was observed by optical microscopy and atomic force microscopy. Initially, high density of hexagonal holes or pits were formed on the etched surface at the time of 40 min with the bimodal size of $20{\mu}m$ or $5{\mu}m$, respectively. However, as the etching time was increased further, the lateral size of the hexagonal holes or pits was increased, and finally, joined and merged together at the time of 100 min. This means that the etching of n-type GaN by phosphoric acidic solutions proceeded through the lateral widening and the merging of initial holes and pits.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.21 no.5
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• pp.149-160
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• 2011

Technique based on the notions of anonymity is one of several ways to achieve the goal of privacy and it transforms the original data into the micro data by some group based methods. The first notion of group based method is ${\kappa}$-anonymity, and it is enhanced by the notions of ${\ell}$-diversity and t-closeness. Since there is the natural tradeoff between privacy and data utility, the development of practical anonymization algorithms is not a simple work and there is still no noticeable algorithm which achieves some combined anonymity conditions. In this paper, we provides a comparative analysis of previous anonymity and accuracy measures. Moreover we propose an algorithm to achieve ${\ell}$-diversity by the block merging method from a micro-data achieving ${\kappa}$-anonymity.

• Journal of Platform Technology
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• v.9 no.4
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• pp.71-78
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• 2021

Self-driving vehicles are increasing as new alternatives to solving problems such as human safety, environment and aging. And such technology development has a great ripple effect on other industries. However, various problems are occurring. The number of casualties caused by self-driving is increasing. Although the collision of fixed obstacles is somewhat decreasing, on the contrary, the technology by active obstacles is still insignificant. Therefore, in this study, in order to solve the core problem of self-driving vehicles, we propose a method of extracting active obstacles on the road. First, a center scene is extracted from a continuous image. In addition, it was proposed to extract activity obstacles using activity size and activity repeatability information from objects included in the center scene. The center scene is calculated using region segmentation and merging. Based on these results, the size of the frequency for each pixel in the region was calculated and the size of the activity of the obstacle was calculated using information that frequently appears in activity. Compared to the results extracted directly by humans, the extraction accuracy was somewhat lower, but satisfactory results were obtained. Therefore, it is believed that the proposed method will contribute to solving the problems of self-driving and reducing human accidents.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.21 no.2
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• pp.132-151
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• 2022

Vehicle localization is one of the core technologies for autonomous driving. Image-based localization provides location information efficiently, and various related studies have been conducted. However, the image-based localization methods using feature points or lane information has a limitation that positioning accuracy may be greatly affected by road and driving environments. In this study, we propose a line segment matching framework for accurate vehicle localization. The proposed framework consists of four steps: line segment extraction, merging, overlap area detection, and MSLD-based segment matching. The proposed framework stably performed line segment matching at a sufficient level for vehicle positioning regardless of vehicle speed, driving method, and surrounding environment.

• The Journal of Engineering Geology
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• v.32 no.3
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• pp.339-350
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• 2022

There are a variety of types in tafoni formed in Miocene tuff from Golgulsa, Gyeongju. Tuff bearing tafoni was quite weathered, composed of quartz, feldspars, micas, vermiculite, chlorite, smectite, and analcite. In the early stage of the tafoni development, tafoni preferentially formed from cavities where volcanic breccias were removed or from microcavities where microcrystals were chemically altered. Small tafoni grew into large one by merging each other. The orientation of tafoni is inversely arranged to slopes, with slight inclination toward the inner cavity. Height, width, and depth of tafoni are closely interrelated: the correlation coefficients are 0.839 (width-height), 0.900 (width-depth), and 0.856 (height-depth), respectively. Removal of walls between tafoni resulted in lenticular or crescent forms, and small tafoni laterally combined to large tafoni. Large tafoni is weak because of high porosity and low strength compared to normal slope. Therefore, systematic monitoring for slope strength, pore proportion and volume, and growth of cavity needs to secure the slope stability where tafoni in Golgulsa is widespread.

• Archives of Plastic Surgery
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• v.49 no.5
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• pp.596-603
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• 2022

Background We suggested an easy and effective harvesting technique to avoid injury to tissues adjacent to the latissimus dorsi (LD). Methods Between 2007 and 2017, breast reconstruction was performed with an LD flap using the "bottom-up" technique. Medical records were retrospectively reviewed. Data on postoperative complications, results, and follow-up were obtained. Nine cadaveric dissections were performed to assess positional relationships between LD and adjacent muscles based on the ribs where relevant muscles and LD attach. Overall, 78 LD flaps were harvested without complications. Results Average age was 45.4 years. The mean operation time was 260minutes. There were no abnormalities or injuries in the adjacent fascia and muscles during the flap harvest. Drains were removed at an average of 21.9 days postoperatively. In all cadavers, there was conjoined fascia between the thoracolumbar and LD fasciae. The average level of the merging point between the LD and external oblique muscle (EOM) was 8.9 to 11.1 ribs. The average level of the overlapping point between the LD and serratus posterior inferior (SPI) was 9.5 to 11.1 ribs. Conclusions There are three dangerous zones during LD flap harvesting. The first zone is where the conjoined fascia encompasses the LD and thoracolumbar fasciae. The second zone is where the LD merges with the EOM and the serratus anterior. The third zone is the lower part where the LD merges with the SPI and EOM. The "bottom-up" technique enables a more meticulous and atraumatic operation by beginner flap surgeons.

• Journal of the Korean Association of Geographic Information Studies
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• v.25 no.4
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• pp.49-62
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• 2022

Borehole Data is geotechnical information provided so that workers can safely perform construction at the field. It creates 3D data and supports viewing as a 3D image. Currently, all Korean companies that develop programs using 3D visualization use the MVS program developed by C Tech Development Corporation. However, the MVS program is a commercial program, and it is difficult to use MVS in 3D related programs developed by Korean Companies. In this paper, we propose to develop a program that can replace MVS to generate a 3D stratum model from clustered borehole information using Python's Gempy open-source. The 3D stratum model program can creates point data for each stratum and can creates a surface for each stratum through interpolation. Then, the 3D stratum model program is completed by merging the surfaces of each stratum. It was confirmed that there was no difference when a 3D model was created and compared with the MVS program and the proposed program from the borehole data of a Goyang area.

• The korean journal of orthodontics
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• v.53 no.1
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• pp.26-34
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• 2023

Objective: The purpose of the present study was to compare the root positions in virtual tooth setups using only crowns in a simulated treatment with those achieved in the actual treatment. Methods: Pre- and post-treatment intraoral and corresponding cone beam computed tomography (CBCT) scans were obtained from 15 patients who underwent orthodontic treatment with premolar extraction. A conventional virtual tooth setup was used for the treatment simulation. Pre- and post-treatment three-dimensional digital tooth models were fabricated by integrating the patients' intraoral and CBCT scans. The simulated root positions in the virtual setup were obtained by merging the crown in the virtual setup and root in the pre-treatment tooth model. The root positions of the simulated and actual post-treatment tooth models were compared. Results: Differences in root positions between the simulated and actual models were > 1 mm in all teeth, and statistically significant differences were observed (p < 0.05), except for the maxillary lateral incisors. The differences in the inter-root angulation were > 1° in all teeth, and statistically significant differences were observed in the maxillary and mandibular canines. Conclusions: The virtual tooth setup using only crown data showed errors over the clinical limits. The clinical application of a virtual setup using crowns and roots is necessary for accurate and precise treatment simulation, particularly in extraction treatment.

• Journal of Broadcast Engineering
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• v.28 no.2
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• pp.194-212
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• 2023

The MPEG immersive video (MIV) coding standard achieved high compression efficiency by removing inter-view redundancy and merging the residuals of immersive video which consists of multiple texture (color) and geometry (depth) pairs. Grouping of views that represent similar spaces enables quality improvement and implementation of selective streaming, but this has not been actively discussed recently. This paper introduces an implementation of group-based encoding into the recent version of MIV reference software, provides experimental results on optimal views and videos per group, and proposes a decision method for optimal number of videos for global immersive video representation by using portion of residual videos.