• 제목/요약/키워드: proper mapping

검색결과 114건 처리시간 0.025초

A Proposal for Generation of Digital Elevation Models in Korea

  • Lee, Chang-Kyung;Park, Byung-Gil;Kim, Young-An;Min Heo
    • 한국측량학회:학술대회논문집
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    • 한국측량학회 2004년도 Korea-Russia Joint Conference on Geometics
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    • pp.73-81
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    • 2004
  • National Geographic Information Institute (NGII) in Korea, through National Geographic Information System (NGIS) Program, has prepared to generate and disseminate digital elevation data for Korea. This is a pilot research to propose a policy for generation, maintenance, and supply of Korea Digital Elevation Data (KDED). Customer demands for accuracy and resolution of DEM was surveyed through questionnaire. In order to investigate the quality, the technical efficiency and the production cost, a tentative DEM in a small test site was generated based on digital topographic maps (original paper map scale 1 :5,000), analytical plotter, and LIDAR. Accuracy standard for KDED was derived based on source data and generation methods. As results of this research, we recommend uniformly spaced grid model for KDED. Its preferable grid space is 5m in urban and its vicinity; and 10m in field and mountainous area. LIDAR has been valuated as a proper KDED generation method fulfilling customers demand for the accuracy.

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초소형 프로젝터를 위한 디지털 LCOS 마이크로 디스플레이의 계조 연구 (A Study on the Gray Scale Method of Digital LCOS Micro-display for Pico-projector Application)

  • 김민석;강정원
    • 반도체디스플레이기술학회지
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    • 제9권2호
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    • pp.87-90
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    • 2010
  • A new SRAM pixel circuit with RESET Transistor of a LCOS display module was designed for a pico-projector application. A dual-block PWM method was also proposed to realize the field sequential color system having only one LCOS panel. 0.29 inch LCOS panel in SVGA resolution was fabricated and the proposed dual-block PWM method was tested with it. Discontinuity of brightness curve was caused due to multi-pulses and it was improved by the adoption of proper mapping table. With the proposed SRAM with RESET pixel circuit and dual-block PWM method, the test images were successfully demonstrated.

Extra-tidal stars around globular clusters NGC 5024 and NGC 5053 and their chemical abundances

  • Chun, Sang-Hyun;Lee, Jae-Joon
    • 천문학회보
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    • 제43권2호
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    • pp.40.2-40.2
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    • 2018
  • NGC 5024 and NGC 5053 are among the most metal-poor globular clusters in the Milky Way. Both globular clusters are considered to be accreted from dwarf galaxies (like Sagittarius dwarf galaxy or Magellanic clouds), and common stellar envelope and tidal tails between globular clusters are also detected. We present a search for extra-tidal cluster member candidates around these globular clusters from APOGEE survey data. Using 20 chemical elements (e.g., Fe, C, Mg, Al) and radial velocities, t-distributed stochastic neighbour embedding (t-SNE), which identifies an optimal mapping of a high-dimensional space into fewer dimensions, was explored, and we find that globular cluster stars are well separated from the field stars in 2-dimensional map from t-SNE. We also find that some stars selected in t-SNE map are placed outside of the tidal radius of the clusters. The proper motion of stars outside tidal radius is also comparable to that of globular clusters, which suggest that these stars are tidally decoupled from the globular clusters. We manually measure chemical abundances for the clusters and extra-tidal stars, and discuss the association of extra-tidal stars with the clusters.

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Automatic Power Line Reconstruction from Multiple Drone Images Based on the Epipolarity

  • Oh, Jae Hong;Lee, Chang No
    • 한국측량학회지
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    • 제36권3호
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    • pp.127-134
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    • 2018
  • Electric transmission towers are facilities to transport electrical power from a plant to an electrical substation. The towers are connected using power lines that are installed with a proper sag by loosening the cable to lower the tension and to secure the sufficient clearance from the ground or nearby objects. The power line sag may extend over the tolerance due to the weather such as strong winds, temperature changes, and a heavy snowfall. Therefore the periodical mapping of the power lines is required but the poor accessibility to the power lines limit the work because most power lines are placed at the mountain area. In addition, the manual mapping of the power lines is also time-consuming either using the terrestrial surveying or the aerial surveying. Therefore we utilized multiple overlapping images acquired from a low-cost drone to automatically reconstruct the power lines in the object space. Two overlapping images are selected for epipolar image resampling, followed by the line extraction for the resampled images and the redundant images. The extracted lines from the epipolar images are matched together and reconstructed for the power lines primitive that are noisy because of the multiple line matches. They are filtered using the extracted line information from the redundant images for final power lines points. The experiment result showed that the proposed method successfully generated parabolic curves of power lines by interpolating the power lines points though the line extraction and reconstruction were not complete in some part due to the lack of the image contrast.

드론 기반 사진측량기법을 활용한 고압 송전선의 처짐량 측정 (Electric Power Line Dips Measurement Using Drone-based Photogrammetric Techniques)

  • 김유종;오재홍;이창노
    • 한국측량학회지
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    • 제35권6호
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    • pp.453-460
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    • 2017
  • 고압 송전선은 전선을 느슨하게 가선하여 약간의 이도를 유지하도록 되어있다. 현재 송전선의 이도를 측정하는 방법은 직접 측량에 의존하고 있고 비교적 정확한 값을 얻을 수 있지만, 송전탑에 직접 승탑하거나 가까이 접근해야하는 위험성 및 어려움이 있다. 본 연구에서는 대상체에 접근하지 않고 3차원 측정을 수행하기 위해 저가의 드론을 활용한 항공사진측량 기법을 사용하였다. 선형 구조물인 송전선은 매핑을 위한 특징점이 존재하지 않기 때문에, 송전선의 방향과 수직이 되도록 에피폴라 라인을 형성하여 입체 사진 처리기법을 통해 송전선의 3차원 매핑을 수행하고, 송전선의 처짐량을 도출하였다. 사진측량기법에 의한 측정 결과 무타겟 토탈스테이션을 사용하여 직접 측정한 두 지점의 송전선의 처짐량과 비교하였을 때 수직 정확도가 15~16cm로 파악되었고 이는 해당 지점 처짐량 대비 5% 이내 및 대상 송전선 이도량의 3% 이내에 해당하는 값이다.

도시경관의 통합적 개선을 위한 색채관리 제도 연구 (A Study on the Color Management System for the Holistic Improvement of Urban Landscape)

  • 김대수;조정송
    • 한국조경학회지
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    • 제31권4호
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    • pp.25-38
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    • 2003
  • The main problems of disordered and congested urban landscape are due to the lack of holistic management that can control various elements of forming a city. Especially, the color of urban landscape is problematic because it is related to individual and social characteristics as well as to physical characteristics. Therefore, temporary expedients that can solve only visualized problems can not be a proper solution for color problems of urban landscape. This study originated from the question about why the color of disordered and congested urban landscape has not been improved. This study aims at directly improving the urban environmental color by finding out what the actual problems related to color are, and what the solutions would be. The goal of this study is to find a holistic systematic problem-solving method. Problems of urban environmental color are identified from both literature review and questionnaires to the expert group, such as environmental planning, design group, and the landscape executive group. Through mapping of relationships among these problems, the intellectual map was made to layout the structures of problems. Based on this method, the structures of problems of urban environmental color were classified into 5 categories: 1) the items related to the administrative structure, 2) the items related to the color management goal and system, 3) the items related to the color planning and design phase, 4) the items related to the color consulting committee, and 5) the items related to the present state of color use. Thus, in order to solve the color problem in urban landscape, practical strategy is strongly required. It is not a temporary expedient but a holistic approach. The solution for the problems of urban environmental color could be divided into 6 types; ‘regulations amendment’,‘color standard amendment’,‘color management plan’,‘color education’, and ‘advertisement for the goal of color management’. Regulations amendment among these types was proposed as the most effective method due to the close relationship with problem categories. Thus, as the solution for the problems of urban environmental color, the ‘color management system’ was suggested. Detailed contents the suggested color management system were divided into three parts; 1) legislation by regulations, ordinance and acts, 2) management by controling the level of guidelines, and 3) the standards for execution of this system.

비유 생성 과정에서 속성과 관계에 대한 고려 여부에 따라 과학영재들이 생성한 비유의 특징 (The Characteristics of Analogies Generated by Science-Gifted Students Depending on the Consideration of Attributes and Relationships in the Processes of Generating Analogies)

  • 김유정;박원;노태희
    • 대한화학회지
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    • 제54권5호
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    • pp.621-632
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    • 2010
  • 이 연구에서는 비유 생성 과정에서 속성과 관계 고려 여부에 따라 과학영재들이 생성한 비유의 특징을 분석하고, 과학 영재 교육프로그램으로 비유 생성 활동의 적용 가능성을 조사하였다. 연구 결과, 과학영재의 비유 생성 과정은 목표 개념과 비유 소재의 속성 및 속성들 간의 관계에 대한 고려 여부에 따라 세 가지 패턴이 나타났으며, 각 패턴에 따라 생성한 비유와 좋은 비유로 선택한 비유 유형 및 적절한 대응의 개수에 차이가 있었다. 대부분의 과학영재들은 다른 목표 개념에 대해서도 비유 생성 활동을 활용하였으며, 비유 생성 활동이 유용하다고 인식하였다. 그러나 비유 생성 과정에서 비유의 소재를 선택하는데 어려움을 겪는 것으로 나타났다. 이 연구 결과는 과학영재의 창의성 계발에 효과적인 교육프로그램으로 비유 생성 활동의 활용 방안을 모색하는데 도움을 줄 수 있을 것이다.

몽골 울란바토르 복드한산 자연보호지역의 산림훼손지 경년변화 분석 (An analysis of year-to-year change of degraded forest land in Mongolia nature reserve Mt. Bogdkhan in Ulaanbaatar)

  • 간조릭;이준우;권형근;최성민;이명교
    • 농업과학연구
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    • 제41권3호
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    • pp.205-211
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    • 2014
  • Focused on Mt. Bogdkhan nature reserve in Mongolia, this study was conducted as a fundamental research to discover a tendency and characteristics of forest damage and to draw up measures for proper plans of forest restoration through an analysis of year-to year change using satellite images. In specific, land cover mapping was conducted by using Landsat images from 1994 to 2011, and then year-to year change was analyzed to investigate the features of forest damage in Mt. Bogdkhan. The results showed that the whole area of a reservation in Mongolia in 2011 was about $416.89km^2$; among them, forest area was $167,87km^2$, accounting for about 40.3%, followed by bare patch and grassland area (58.6%) and urban dry area (1.1%). In particular, compared in 1994, the area of forest in 2011 has increased by $6.12km^2$; while bare patch and grassland area has decreased by $10.81km^2$. Primary causes of forest degradation occurred in Mt. Bogdkhan nature reserve included illegal logging for fuel, forest and grassland degradation caused by domestic animals grazing, man-made forest fire, and disaster caused by insect pest.

B3G 네트워크에서 SLA 기반 QoS 매핑을 위한 연구 (A Study of QoS Mapping based on SLA in B3G Networks)

  • 문현주;이진관;정규철;이종찬;박상준;신성윤
    • 한국컴퓨터정보학회논문지
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    • 제16권3호
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    • pp.157-165
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    • 2011
  • B3G 네트워크에서 SLA 기반 QoS 관리방안은 서비스 이용자와 서비스 제공자 사이에서 이루어지는 협약으로 서비스 제공자는 협약된 사항을 근거로 사용자에게 통신 서비스를 제공하게 된다. 서비스 제공자는 협의된 서비스 레벨을 유지하기 위한 QoS 방안을 제공하며 이는 정책레벨에서 시스템 레벨까지의 세부방안을 포괄하여 다룬다. 협약된 서비스 정책에 의하여 서비스 제공자는 서비스 사용자와의 협약에 맞추어 정해진 QoS를 제공하며, 따라서 서비스 사용자는 신뢰적으로 서비스를 제공받을 수 있다. 따라서 본 논문에서는 B3G 네트워크에서 SLA 기반에서 이루어질 수 있는 서비스 협약을 통하여 사용자 서비스 제공을 위한 융합 망의 QoS 매핑에 대한 방안을 제안한다.

관계형 데이터베이스에서의 시맨틱 기반 키워드 탐색 시스템 (Semantic-based Keyword Search System over Relational Database)

  • 양영휴
    • 한국컴퓨터정보학회논문지
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    • 제18권12호
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    • pp.91-101
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    • 2013
  • 키워드의 모호성은 효율적인 키워드 탐색에 있어서 일반적인 이슈가 되어왔는데, 이 모호성은 탐색결과의 신뢰성에 큰 영향을 줄 수 있으며, 기본적으로 질의에 사용된 용어 자체가 가지는 문맥상 의미의 모호함에 기인한다. 질의 자체의 모호함뿐만 아니라, 사용자들이 그 탐색 결과를 적절하게 해석하기 위해 결과에 나타나는 키워드간의 관계도 중요하므로 명확하게 명시 되어야 한다. 이 논문에서는 기존의 질의 용어와 스키마 용어/인스턴스간의 키워드 매핑기법을 적용하여 키워드 탐색의 모호성을 해결한다. 용어간의 매핑에서는 질의 키워드와 스키마 용어간의 구문적 유사성은 물론 시맨틱 유사성까지 고려하기 때문에 기존의 시스템에 비해 매핑과 정밀도가 50% 이상 상승하는 결과를 얻을 수 있다. 탐색결과에 나타나는 용어간의 불분명한 관계를 점 더 명확하게 나타내기 위하여 시맨틱 웹 기술을 적용하여 키워드간의 의미 있는 관계를 더 많이 지식베이스 내에서 찾을 수 있도록 하였다.