• Title/Summary/Keyword: 김용하

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Pancreatic Lipase Inhibitors Isolated from the Leaves of Cultivated Mountain Ginseng (Panax ginseng) (산양삼 잎으로부터 Pancreatic lipase 저해 활성물질의 분리)

  • Hong, Ju-Yeon;Shin, Seung-Ryeul;Bae, Man-Jong;Bae, Jong-Sup;Lee, In-Chul;Kwon, O-Jun;Jung, Ji-Wook;Kim, Yong-Han;Kim, Tae-Hoon
    • Food Science and Preservation
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    • v.17 no.5
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    • pp.727-732
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    • 2010
  • Activity-guided fractionation of an ethyl acetate (EtOAc)-soluble portion of an ethanolic extract from the leaves of cultivated mountain ginseng, using pancreatic lipase inhibition assay, led to the isolation and identification of three flavonoids of a previously described structure, kaempferol-3-O-sophoroside (I), kaempferol-3-O-${\beta}$-Dglucopyranoside (astragalin, II) and kaempferol (III). All compounds (I.III) showed pancreatic lipase inhibitory activities, with $IC_{50}$ values ranging from $20.3{\pm}2.2$ to $9.1{\pm}1.5$ ${\mu}M$, kaempferol (III) showed the most potent inhibitory activity with an $IC_{50}$ of $9.1{\pm}1.5$ ${\mu}M$. The level of activity may depend on the number of C-3 glucosyl group(s) linked to the kaempferol backbone, and the isolated compounds may have promise as pancreatic lipase inhibitors.

A Study on the International Discussion of Digital Trade Norms (디지털 무역규범의 국제적 논의에 관한 연구)

  • Hwang, Ji-Hyeon;Kim, Yong-Il
    • Journal of Convergence for Information Technology
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    • v.11 no.10
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    • pp.93-100
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    • 2021
  • With the spread of digital trade, the share of digital trade under the global trade environment is increasing. However, since there is no international digital trade standard, the discussion to establish a new trade rule has important significance. Countries around the world are implementing digital trade policies in consideration of their own interests, but different regulatory policies are causing trade conflicts. In order to provide safeguards against personal information infringement due to the free movement of data across borders, major countries around the world have taken measures to localize data, and the EU has enacted GDPR. And the United States regards the imposition of the digital tax as a trade barrier, and some countries oppose the implementation of the digital tax for fear of negative impact on their countries. However, discussions on the global digital tax, centered on the OECD and the G20 are making progress. As it is highly likely that a digital tax agreement will be drawn up within this year, countermeasures must also be prepared. Therefore, this study presents implications for the future direction of Korea's trade policy by examining recent trends in digital trade norms and analyzing major issues in digital trade.

Wildfire-induced Change Detection Using Post-fire VHR Satellite Images and GIS Data (산불 발생 후 VHR 위성영상과 GIS 데이터를 이용한 산불 피해 지역 변화 탐지)

  • Chung, Minkyung;Kim, Yongil
    • Korean Journal of Remote Sensing
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    • v.37 no.5_3
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    • pp.1389-1403
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    • 2021
  • Disaster management using VHR (very high resolution) satellite images supports rapid damage assessment and also offers detailed information of the damages. However, the acquisition of pre-event VHR satellite images is usually limited due to the long revisit time of VHR satellites. The absence of the pre-event data can reduce the accuracy of damage assessment since it is difficult to distinguish the changed region from the unchanged region with only post-event data. To address this limitation, in this study, we conducted the wildfire-induced change detection on national wildfire cases using post-fire VHR satellite images and GIS (Geographic Information System) data. For GIS data, a national land cover map was selected to simulate the pre-fire NIR (near-infrared) images using the spatial information of the pre-fire land cover. Then, the simulated pre-fire NIR images were used to analyze bi-temporal NDVI (Normalized Difference Vegetation Index) correlation for unsupervised change detection. The whole process of change detection was performed on a superpixel basis considering the advantages of superpixels being able to reduce the complexity of the image processing while preserving the details of the VHR images. The proposed method was validated on the 2019 Gangwon wildfire cases and showed a high overall accuracy over 98% and a high F1-score over 0.97 for both study sites.

Waveform Decomposition of Airborne Bathymetric LiDAR by Estimating Potential Peaks (잠재적 피크 추정을 통한 항공수심라이다 웨이브폼 분해)

  • Kim, Hyejin;Lee, Jaebin;Kim, Yongil;Wie, Gwangjae
    • Korean Journal of Remote Sensing
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    • v.37 no.6_1
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    • pp.1709-1718
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    • 2021
  • The waveform data of the Airborne Bathymetric LiDAR (ABL; LiDAR: Light Detection And Ranging) system provides data with improved accuracy, resolution, and reliability compared to the discrete-return data, and increases the user's control over data processing. Furthermore, we are able to extract additional information about the return signal. Waveform decomposition is a technique that separates each echo from the received waveform with a mixture of water surface and seabed reflections, waterbody backscattering, and various noises. In this study, a new waveform decomposition technique based on a Gaussian model was developed to improve the point extraction performance from the ABL waveform data. In the existing waveform decomposition techniques, the number of decomposed echoes and decomposition performance depend on the peak detection results because they use waveform peaks as initial values. However, in the study, we improved the approximation accuracy of the decomposition model by adding the estimated potential peak candidates to the initial peaks. As a result of an experiment using waveform data obtained from the East Coast from the Seahawk system, the precision of the decomposition model was improved by about 37% based on evaluating RMSE compared to the Gaussian decomposition method.

Object-Based Road Extraction from VHR Satellite Image Using Improved Ant Colony Optimization (개선된 개미 군집 최적화를 이용한 고해상도 위성영상에서의 객체 기반 도로 추출)

  • Kim, Han Sae;Choi, Kang Hyeok;Kim, Yong Il;Kim, Duk-Jin;Jeong, Jae Joon
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.37 no.3
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    • pp.109-118
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    • 2019
  • Road information is one of the most significant geospatial data for applications such as transportation, city planning, map generation, LBS (Location-Based Service), and GIS (Geographic Information System) database updates. Robust technologies to acquire and update accurate road information can contribute significantly to geospatial industries. In this study, we analyze the limitations of ACO (Ant Colony Optimization) road extraction, which is a recently introduced object-based road extraction method using high-resolution satellite images. Object-based ACO road extraction can efficiently extract road areas using both spectral and morphological information. This method, however, is highly dependent on object descriptor information and requires manual designations of descriptors. Moreover, reasonable iteration closing point needs to be specified. In this study, we perform improved ACO road extraction on VHR (Very High Resolution) optical satellite image by proposing an optimization stopping criteria and descriptors that complements the limitations of the existing method. The proposed method revealed 52.51% completeness, 6.12% correctness, and a 51.53% quality improvement over the existing algorithm.

Optimal Parameter Analysis and Evaluation of Change Detection for SLIC-based Superpixel Techniques Using KOMPSAT Data (KOMPSAT 영상을 활용한 SLIC 계열 Superpixel 기법의 최적 파라미터 분석 및 변화 탐지 성능 비교)

  • Chung, Minkyung;Han, Youkyung;Choi, Jaewan;Kim, Yongil
    • Korean Journal of Remote Sensing
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    • v.34 no.6_3
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    • pp.1427-1443
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    • 2018
  • Object-based image analysis (OBIA) allows higher computation efficiency and usability of information inherent in the image, as it reduces the complexity of the image while maintaining the image properties. Superpixel methods oversegment the image with a smaller image unit than an ordinary object segment and well preserve the edges of the image. SLIC (Simple linear iterative clustering) is known for outperforming the previous superpixel methods with high image segmentation quality. Although the input parameter for SLIC, number of superpixels has considerable influence on image segmentation results, impact analysis for SLIC parameter has not been investigated enough. In this study, we performed optimal parameter analysis and evaluation of change detection for SLIC-based superpixel techniques using KOMPSAT data. Forsuperpixel generation, three superpixel methods (SLIC; SLIC0, zero parameter version of SLIC; SNIC, simple non-iterative clustering) were used with superpixel sizes in ranges of $5{\times}5$ (pixels) to $50{\times}50$ (pixels). Then, the image segmentation results were analyzed for how well they preserve the edges of the change detection reference data. Based on the optimal parameter analysis, image segmentation boundaries were obtained from difference image of the bi-temporal images. Then, DBSCAN (Density-based spatial clustering of applications with noise) was applied to cluster the superpixels to a certain size of objects for change detection. The changes of features were detected for each superpixel and compared with reference data for evaluation. From the change detection results, it proved that better change detection can be achieved even with bigger superpixel size if the superpixels were generated with high regularity of size and shape.

Intrusion of the extruded maxillary central incisor using skeletal anchorage system and unilateral segmental intrusion arch (골성 고정원과 편측 분절호선을 이용한 정출된 상악 중절치의 압하 치료)

  • Kwon, Eun-Young;Baek, Young-Jae;Park, Soo-Byung;Kim, Seong-sik;Kim, Yong-il;Choi, Youn-kyung
    • Journal of Dental Rehabilitation and Applied Science
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    • v.35 no.3
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    • pp.180-190
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    • 2019
  • Patients who have a moderate periodontitis with pathologic tooth migration of maxillary incisors, it is necessary not only periodontal treatment for reduce periodontal inflammation, but also orthodontic treatment to teeth repositioning. For orthodontic treatment, it is necessary to apply less force and careful considerations of the center of resistance of the tooth and optimal force of tooth movement. At this time, the segmental arch applied only to the target teeth, is more effective and predictable, because applied force and direction can be controlled. In addition, to design the orthodontic appliance that can prevent the unwanted tooth movement that used as an anchorage is important. In recent years, various types of skeletal anchorage system have been used for preventing loss of the anchorage. We reported the patient who had extruded maxillary central incisor due to pathologic tooth migration, treated by a successful periodontal-orthodontic multidisciplinary treatment using an orthodontic appliance designed to apply less traumatic force and reduce an anchorage loss.

A Study on Improvements and Current Issues of Records and Archives Management in Special Project Teams at the University : focused on the J University (대학특별사업단 기록물 관리 현황분석 및 개선방안 연구 J대학을 중심으로)

  • Choi, Hyo Young;Kim, Chan Young;Kim, Yong
    • The Korean Journal of Archival Studies
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    • no.50
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    • pp.97-138
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    • 2016
  • This study presents the problems in the records management of special project teams at J University. Methods for the improvement plan were also proposed in this study. To achieve these objectives, five special project teams from J University, which were supported by the Ministry of Education, were selected. To collect relevant information, twelve staff members and experts were then interviewed. The records produced by the projects should be managed as evidence of the project evaluation and transparent budget execution. Proper management can be a good material for research. However, the management of project teams is vulnerable in comparison with the records of other universities. The main reason is that although the project team produces various types of records, it has not been recognized as the Department of Processing. Another reason is that the project teams are temporary institutions and do not possess authority over the entire project process. To solve the aforementioned problems, this study proposes improvement plans in the following aspects: institutional, cognitive, administrational, and systemic. In the institutional and cognitive aspects, policy and regulation were set up. In the administrational aspect, the relation and role of each element were defined. In conclusion, the plans for building the Combined Archives System were suggested. In addition the methods on how to connect with the KORUS-which will be introduced in 2017-and the system currently being used are proposed.

A Study on Availability of AtoM for Recording Korean Wave Culture Contents : A Case of K-Food Contents (한류문화콘텐츠의 기록화를 위한 AtoM 활용 방안에 관한 연구 K-Food 콘텐츠를 중심으로)

  • Shim, Gab-yong;Yoo, Hyeon-Gyeong;Moon, Sang-Hoon;Lee, Youn-Yong;Lee, Jeong-Hyeon;Kim, Yong
    • The Korean Journal of Archival Studies
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    • no.43
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    • pp.5-42
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    • 2015
  • Korean wave 3.0 is focused on 'K-Culture' which includes traditional culture, cultural art as well as existing culture contents as a keyword. It considers everything about Korean culture as materials of Korean wave culture contents. Since Korean wave culture contents reflect contemporary social aspect, it needs to preserve those contents as archives and records which have the important value of evidence. With this social environment, this study aims to implement RMS based on AtoM that manages various kinds of Korean wave culture contents through analysis of management situation of those materials. Recently, it is in progress individually to manage them through organizations dealing with korean cultures such as K-Pop, K-Food, K-Movie. However, it has problems in accumulating information and reproducing high quality contents because of lack of coordination among organizations. To solve the problems, this study proposed RMS based on open source software Access to Memory(AtoM) for managing and recording Korean wave culture contents. AtoM provides various functions for managing records and archives such as accumulation, classification, description and browsing. Furthermore AtoM is for free as open source software and easy to implement and use. Thus, this study implemented RMS based on AtoM to methodically manage korean wave culture contents by functional requirements of RMS. Also, this study considered contents relating K-Food as an object to collect, classify, and describe. To describe it, this study selected ISAD(G) standard.

Temporary replacement of congenital missing incisors on mandible using temporary anchorage devices in growing patient: 2-year follow-up (성장기 아동에서 교정용 골성 고정원을 이용한 선천 결손 하악 전치의 임시 보철 수복: 2년 경과 관찰)

  • Choi, Youn-kyung;Kwon, Eun-Young;Jung, Kyung-Hwa;Choi, Na-Rae;Park, Soo-Byung;Kim, Seong-sik;Kim, Yong-il
    • Journal of Dental Rehabilitation and Applied Science
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    • v.36 no.4
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    • pp.272-281
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    • 2020
  • Agenesis of permanent tooth in adolescent patients can be treated either by orthodontic treatment for space closure or by maintaining the space until implant restoration can be carried out in adult. However, gradual atrophy of alveolar bone width makes it difficult to restore the prosthesis in the future or may cause unaesthetic results. Therefore, maintaining of not only the missing space but also the alveolar bone width should be considered. This case is a treatment whereby a temporary replacement of missing 2 mandibular incisors in adolescent patient was carried out using 2 temporary anchorage devices (TADs). Two TADs were placed horizontally 2 - 3 mm below the top of alveolar ridge, and fixed with artificial teeth by stainless steel wires extended. During the 2 year follow-up, neither gingival inflammation nor loss of the TADs have occurred. In the radiographic evaluation, the growth of the adjacent alveolar bone was not inhibited, and the width of the alveolar bone was maintained.