• Title/Summary/Keyword: photographic information

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A Study on the Rotating Displacement Measurement of Rigid Body by ESPI Method (ESPI법에 의한 강체 회전 변위 측정에 관한 연구)

  • 김경석;홍명석
    • Transactions of the Korean Society of Automotive Engineers
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    • v.1 no.2
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    • pp.125-133
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    • 1993
  • Electronic Speckle Pattern Interferometry(ESPI) using a CW laser, a video system and image processor was applied to the rotating displacement of rigid body. ESPI require no special surface preparation or attachments and displacements between any two arbitrary points on the surface can be measured. The characteristic speckle pattern formed when imaging a scattering surface illuminated by laser light retains phase information, which can be used for interferometric measurement of surface displacement. The application of this principle to measuring in-plane displacement resolved in one direction is described, together with the novel use of television equipment to detect and process the information contained in the speckle pattern. This is faster, and more convenient and versatile than customary photographic methods.

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Thermal Characteristics and Heatsink Modeling. for IGBT (IGBT의 열 특성 및 히트싱크 모델링)

  • Ryu, Se-Hwan;Bea, Kyung-Kuk;Shin, Ho-Chul;Ahn, Hyung-Keun;Han, Deuk-Young
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2007.06a
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    • pp.172-173
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    • 2007
  • As the power density and switching frequency increase, thermal analysis of power electronics system becomes imperative. The thermal analysis provides valuable information on the semiconductor rating, long-term reliability. In this paper, thermal distribution of the Non Punchthrough(NPT) Insulated Gate Bipolar Transistor has been studied. For analysis of thermal distribution, we obtained experimental and simulation results by using finite element simulator, Ansys and by using photographic infrared thermometer, we compared experimental date with simulation result. and got good agreement. Also this paper provided thermal distribution of IGBT connected to heat sinks. and this results will be good information to design optimal heat sink for IGBT.

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Diel Activity Patterns of Water Deer (Hydropotes inermis) and Wild Boar (Sus scrofa) in a Suburban Area Monitored by Long-term Camera-Trapping (장기 카메라트래핑 모니터링 자료를 활용한 도시근교의 고라니 및 멧돼지 일주기성 연구)

  • Han, Youn-Ha;Shin, Won-Hyeop;Kim, Ji-Hwan;Kim, Do-Hee;Yun, J i-Weon;Yi, Sok-Young;Kim, Yong-Hwan;Lee, Seung-Hyeon;Song, Young-Keun
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.27 no.2
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    • pp.55-65
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    • 2024
  • This study aimed to figure out diel activity patterns of water deer and wild boar, whose habitat is disturbed by human activity in a suburban area. Photographic data of water deer and wild boar collected by 18 camera traps from January 2021 to November 2022 was categorized into four diel periods (dawn, day, dusk, and night), and converted into frequencies per 100 CTD (Camera Trap-Days) for seasonal and spatial diel activity pattern analysis. Water deer exhibited intense nocturnality in fall, and wild boar did in fall and winter. During the fall, water deer's night-time capture rate was the highest (61.9%), and day-time photographic rate was the lowest (13.9%) among other seasons. During the fall and winter, wild boar's night-time photographic rate was relatively high (77.6%, 78.0%, respectively), and day-time photographic rate was relatively low (0.7%, 1.8%) in comparison with other seasons. In spatial diel activity analysis, both water deer and wild boar showed a tendency to avoid humans, especially near trails during day-time hours. The day-time photographic rate of water deer in trail-near group was 12.1% and trail-far group was 24.6%. The day-time photographic rate of wild boar was 3.4%, 5.7%, respectively. Because the diel activity patterns of wildlife reflect human disturbance, this study provides useful ecological information for developing appropriate management plans for the coexistence of water deer and wild boar in suburban areas.

Analysis of the Changes for Natural Environment by Geo-Spatial Information Database of Aerial Photo (항공사진의 지형공간정보 자료기반에 의한 자연환경변화의 분석)

  • Kang, In-Joon;Kwak, Jae-Ha;Park, Kie-Tae
    • Journal of Korean Society for Geospatial Information Science
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    • v.1 no.2 s.2
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    • pp.159-166
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    • 1993
  • Decrease of forest is seriously caused by urbanization. Photographic interpretation is the act of examining photographic images for the purpose of identifying objects and judging their significance. A systematic study of aerial photographs usually involves a consideration of the basic characteristics of photographic images. Seven of these characteristics are shape, size, pattern, shadow, tone, texture, and site. Aerial photographs contain a detailed record of the ground at the time of exposure. Authors blow the changes of natural environment by database for interpretation of aerial photo. In this paper, authors choose the Pusan National University located at the Kum-Joung Koo, Pusan as model area. Ten year of interval in 1980 and 1990, authors know the rate of forest decreasing is approximately 41 percents and the necessity of the protection of foreast. Authors suggest the combination of construction and protection of environment.

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The Photography as Technological Aesthetics (데크놀로지 미학으로서의 사진)

  • Jin, Dong-Sun
    • Journal of Science of Art and Design
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    • v.11
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    • pp.221-249
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    • 2007
  • Today, photography is facing to the crisis of identity and dilemma of ontology from the digital imaging process in the new technology form. It is very important points to say rethinking of the traditional photographic medium, that has changed the way we view the world and ourselves is perhaps an understatement and that photography has transformed our essential understanding of reality. Now, no longer are photographic images regarded as the true automatic recording, innocent evidence and the mirror to the reality. Rather, photography constructs the world for our entertainment, helping to create the comforting illusions by which we live. The recognition that photographs are not constructions and reflections of reality, is the basis for the actual presence within the contemporary photographic world. It is shock. This thesis's aim is to look for the problems of photographic identity and ontological crisis that is controlling and regulating digital photographic imagery, allowing the reproduction of the electronic simulations era. Photography loses its special aesthetic status and becomes no more true information and, exclusively evidence by traditional film and paper that appeared both as a technological accuracy and as a medium-specific aesthetic. The result, photography is facing two crises, one is the photographic ontology(the introduction of computerized digital images) and the other is photographic epistemology(having to do broader changes in ethics, knowledge and culture). Taken together, these crises apparently threaten us with the death of photography, with the 'end' of photography and the culture it sustains. The thesis's meaning is to look into the dilemma of photography's ontology and epistemology, especially, automatical index and digital codes from its origin, meaning, and identity as the technological medium. Thus, in particular, thesis focuses on the analog imagery presence, from the nature in the material world, and the digital imagery presence from the cultural situations in our society. And also thesis's aim is to examine the main issues of the history of photography has been concentrated on the ontological arguments since the discovery of photography in 1839. Photography has never been only one static technology form. Rather, its nearly two centuries of technological development have been marked by numerous, competing of technological innovation and self revolution from the dual aspects. This thesis examines recent account of photography by the analysis of the medium's concept, meaning, identity between film base image and digital base image from the aspects of photographic ontology and epistemology. Thus, the structure of thesis is fairy straightforward to examine what appear to be two opposing view of photographic conditions and ontological situations. Thesis' view contrasts that figure out the value of photography according to its fundamental characteristic as a medium. Also, it seeks a possible solution to the dilemma of photographic ontology through the medium's origin from the early years of the nineteenth century to the raising questions about the different meaning(analog/digital) of photography, now. Finally, this thesis emphasizes and concludes that the photographic ontological crisis reflects to the paradoxical dynamic structure, that unsolved the origins of the medium, itself. Moreover, even photography is not single identity of the photographic ontology, and also can not be understood as having a static identity or singular status from the dynamic field of technologies, practices, and images.

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A Study on 3D Model Building of Drones-Based Urban Digital Twin (드론기반 도심지 디지털트윈 3차원 모형 구축에 관한 연구)

  • Lim, Seong-Ha;Choi, Kyu-Myeong;Cho, Gi-Sung
    • Journal of Cadastre & Land InformatiX
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    • v.50 no.1
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    • pp.163-180
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    • 2020
  • In this study, to build a spatial information infrastructure, which is a component of a smart city, a 3D digital twin model in the downtown area was built based on the latest spatial information acquisition technology, the drone. Several analysis models were implemented by utilizing. While the data processing time and quality of the three types of drone photogrammetry software are different, the accuracy of the construction model is ± 0.04 in the N direction and ± 0.03m in the E direction. In the m and Z directions, ± 0.02m was found to be less than 0.1m, which is defined as the allowable range of surveying performance and inspection performance for the boundary point in the area where the registration of the boundary point registration is executed. 1: 500 to 1 of the aerial survey work regulation: The standard deviation, which is the error limit of the photographic reference point of the 600 scale, appeared within 0.14 cm, and it was found that the error limit of the large scale specified in the cadastral and aerial survey was satisfied. In addition, in order to increase the usability of smart city realization using a drone-based 3D urban digital twin model, the model built in this study was used to implement Prospect right analysis, landscape analysis, Right of light analysis, patrol route analysis, and fire suppression simulation training. Compared to the existing aerial photographic survey method, it was judged that the accuracy of the naked eye reading point is more accurate (about 10cm) than the existing aerial photographic survey, and it is possible to reduce the construction cost compared to the existing aerial photographic survey at a construction area of about 30㎢ or less.

Photographic Virtual Reality-based Education Systems for Cultural Property Learning (문화재 학습을 위한 PVR 기반 교육 시스템)

  • Han, Seon-Kwan;Yoon, Kyoung-Nam
    • Journal of The Korean Association of Information Education
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    • v.13 no.2
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    • pp.159-168
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    • 2009
  • This study is a project case research on PVR-based e-book systems for the cultural property learning effectively. In this study, we designed and implemented the systems and contents using a photographic virtual reality technique. This system could provide the students an effectiveness of virtual experience such as a student is at place that has the cultural property. Moreover we developed the educational contents in image DB. We also converted these contents into e-book typed contents that the students easily searched and used the system in class. This systems were applied the students in elementary school. As the result of applying, we found that the PVR-based e-book systems were more effective than plain web-based systems. This study will give advanced education environment to students as well as teachers in future.

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Watermaking Method for Digital Images in the Wavelet Domain (웨이블릿 영역에서의 디지털 영상 워터마킹 방법)

  • Kim, Young-Sik;Kwon, O-Hyung;Park, Rae-Hong
    • Journal of the Korean Institute of Telematics and Electronics S
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    • v.36S no.12
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    • pp.27-33
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    • 1999
  • A wavelet based multiresolution watermarking method using the human visual system (HVS) is proposed, in which a different number of watermarks, in proportion to the energy contained in each band, are embedded into each band. Experiments with various test images show that the proposed three-level wavelet based method is robust to various attacks such as joint photographic experts group (JPEG) compression, smoothing, cropping, collusion, multiple watermarking, and so on.

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A Study on Photographic 3D Modeling Techniques for Their Enhancements (실사적인 3차원 물체 모델링 기법 개선)

  • Lee, Jong-Soo
    • The KIPS Transactions:PartB
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    • v.10B no.2
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    • pp.157-162
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    • 2003
  • In this paper, in-depth considerations are given to various techniques suggested for photographic 3D modelling and possible enhancements of the techniques are discussed. It is found that both the improvement of fundamental matrix estimation techniques and the stereo image rectification processing stage are necessary for more accurate 3D modelling.