• Title/Summary/Keyword: digital sensing

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Feasibility Study on Producing 1:25,000 Digital Map Using KOMPSAT-5 SAR Stereo Images (KOMPSAT-5 레이더 위성 스테레오 영상을 이용한 1:25,000 수치지형도제작 가능성 연구)

  • Lee, Yong-Suk;Jung, Hyung-Sup
    • Korean Journal of Remote Sensing
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    • v.34 no.6_3
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    • pp.1329-1350
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    • 2018
  • There have been many applications to observe Earth using synthetic aperture radar (SAR) since it could acquire Earth observation data without reference to weathers or local times. However researches about digital map generation using SAR have hardly been performed due to complex raw data processing. In this study, we suggested feasibility of producing digital map using SAR stereo images. We collected two sets, which include an ascending and a descending orbit acquisitions respectively, of KOMPSAT-5 stereo dataset. In order to suggest the feasibility of digital map generation from SAR stereo images, we performed 1) rational polynomial coefficient transformation from radar geometry, 2) digital resititution using KOMPSAT-5 stereo images, and 3) validation using digital-map-derived reference points and check points. As the results of two models, root mean squared errors of XY and Z direction were less than 1m for each model. We discussed that KOMPSAT-5 stereo image could generated 1:25,000 digital map which meets a standard of the digital map. The proposed results would contribute to generate and update digital maps for inaccessible areas and wherever weather conditions are unstable such as North Korea or Polar region.

Monitoring canopy phenology in a deciduous broadleaf forest using the Phenological Eyes Network (PEN)

  • Choi, Jeong-Pil;Kang, Sin-Kyu;Choi, Gwang-Yong;Nasahara, Kenlo Nishda;Motohka, Takeshi;Lim, Jong-Hwan
    • Journal of Ecology and Environment
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    • v.34 no.2
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    • pp.149-156
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    • 2011
  • Phenological variables derived from remote sensing are useful in determining the seasonal cycles of ecosystems in a changing climate. Satellite remote sensing imagery is useful for the spatial continuous monitoring of vegetation phenology across broad regions; however, its applications are substantially constrained by atmospheric disturbances such as clouds, dusts, and aerosols. By way of contrast, a tower-based ground remote sensing approach at the canopy level can provide continuous information on canopy phenology at finer spatial and temporal scales, regardless of atmospheric conditions. In this study, a tower-based ground remote sensing system, called the "Phenological Eyes Network (PEN)", which was installed at the Gwangneung Deciduous KoFlux (GDK) flux tower site in Korea was introduced, and daily phenological progressions at the canopy level were assessed using ratios of red, green, and blue (RGB) spectral reflectances obtained by the PEN system. The PEN system at the GDK site consists of an automatic-capturing digital fisheye camera and a hemi-spherical spectroradiometer, and monitors stand canopy phenology on an hourly basis. RGB data analyses conducted between late March and early December in 2009 revealed that the 2G_RB (i.e., 2G - R - B) index was lower than the G/R (i.e., G divided by R) index during the off-growing season, owing to the effects of surface reflectance, including soil and snow effects. The results of comparisons between the daily PEN-obtained RGB ratios and daily moderate-resolution imaging spectroradiometer (MODIS)-driven vegetation indices demonstrate that ground remote sensing data, including the PEN data, can help to improve cloud-contaminated satellite remote sensing imagery.

Detection of low salinity water in the northern East China Sea in summer using ocean color remote sensing

  • Suh, Young-Sang;Jang, Lee-Hyun;Lee, Na-Kyung;Kim, Bok-Kee
    • Proceedings of the KSRS Conference
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    • 2002.10a
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    • pp.649-654
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    • 2002
  • In summer season of 1998, a huge flood occurred around the Yangtze River in the eastern China. The low salinity water less than 28 psu from the river was detected around the southeastern part of the Jeju Island which is located in the southern part of the Korean peninsula. We studied how to detect low salinity water from the Yangtze River, which gives terrible damages to the Korean fisheries. We got the relationships between low surface salinity, turbid water from the Yangtze River and digital ocean color using remote sensing of SeaWiFS satellite in the northern East China Sea in summer seanson of 1998, 1999, 2000 and 2001. The charts of salinity in the northern East China Sea were made by the regenerating of the satellite ocean color data with the formula from the relationships between low salinity, in situ turbid water (transparency) and satellite ocean color.

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Reliability and Validity of a Force-Sensing Resistor for the Measurement of Static Hindlimb Weight Distribution in Beagle Dogs

  • Heo, Su-Young;Jeong, Heejun;Jeong, Jaemin;Jeong, Seong Mok;Lee, HaeBeom
    • Journal of Veterinary Clinics
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    • v.35 no.5
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    • pp.206-210
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    • 2018
  • The purpose of this study was to evaluate the reliability and validity of the Force-Sensing Resistor (FSR) for measurement of static hindlimb weight distribution in beagle dogs and to compare these results to a Digital Weighing Scale (DWS). Nine healthy beagle dogs were recruited for this study. Static weight distribution was evaluated four times at intervals of 5 days with each device and two observers to calculate the intra- and interobserver reliability. The intraclass correlation coefficient (ICC) values of the FSR for intraobserver reliability were moderate to good (0.74). The results for the DWS showed poor to moderate (0.56) ICC values for intraobserver reliability. The ICC values for interobserver reliability were 0.53 and 0.61 for FSR and DWS, respectively, indicating poor to moderate agreement. Our findings suggest that the Force-Sensing Resistor can be used to measure static weight distribution in veterinary medicine. However, caution should be taken when comparing measured values of static weight distribution obtained utilizing both the FSR and DWS due to their low positive correlation (R = 0.41, p < 0.01).

Mixed-Mode Simulations of Touch Screen Panel Driver with Capacitive Sensor based on Improved Charge Pump Circuit (개선된 charge pump 기반 정전 센싱 회로를 이용한 터치 스크린 패널 드라이버의 혼성모드 회로 분석)

  • Yeo, Hyeop-Goo
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.16 no.2
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    • pp.319-324
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    • 2012
  • This paper introduces a 2-dimensional touch screen panel driver based on an improved capacitive sensing circuit. The improved capacitive sensing circuit based on charge pump can eliminate the remaining charges of the intermediate nodes, which may cause output voltage drift. The touch screen panel driver with mixed-mode circuits was built and simulated using Cadence Spectre. Verilog-A models the digital circuits effectively and enables them to interface with analog circuits easily. From the simulation results, we can verify the reliable operations of the simple structured touch screen panel driver based on the improved capacitive sensing circuit offering no voltage drift.

ANALYSIS OF THE CHARACTERISTICS ABOUT GYEONG-GANG FAULT ZONE THROUGH REMOTE SENSING TECHNIQUES

  • Hwang, Jin-Kyong;Choi, Jong-Kuk;Won, Joong-Sun
    • Proceedings of the KSRS Conference
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    • 2008.10a
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    • pp.196-199
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    • 2008
  • Lineament is defined generally as a linear feature or pattern on interpretation of a satellite image and indicates the geological structures such as faults and fractures. For this reason, a lineament extraction and analysis using remote sensing images have been widely used for mapping large areas. The Gyeong-gang Fault is a NNE trending structure located in Gangwon-do and Kyeonggi-do district. However, a few geological researches on that fault have been carried out and its trace or continuity is ambiguous. In this study, we investigate the geologic features at Gyeong-gang Fault Zone using LANDSAT ETM+ satellite image and SRTM digital elevation model. In order to extract the characteristics of geologic features effectively, we transform the LANDSAT ETM+ image using Principal Component Analysis (PCA) and create a shade relief from SRTM data with various illumination angles. The results show that it is possible to identify the dimensions and orientations of the geologic features at Gyeong-gang Fault Zone using remote sensing data. An aerial photograph interpretation and a field work will be future tasks for more accurate analysis in this area.

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Footprint extraction of urban buildings with LIDAR data

  • Kanniah, Kasturi Devi;Gunaratnam, Kasturi;Mohd, Mohd Ibrahim Seeni
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.113-119
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    • 2003
  • Building information is extremely important for many applications within the urban environment. Sufficient techniques and user-friendly tools for information extraction from remotely sensed imagery are urgently needed. This paper presents an automatic and manual approach for extracting footprints of buildings in urban areas from airborne Light Detection and Ranging (LIDAR) data. First a digital surface model (DSM) was generated from the LIDAR point data. Then, objects higher than the ground surface are extracted using the generated DSM. Based on general knowledge on the study area and field visits, buildings were separated from other objects. The automatic technique for extracting the building footprints was based on different window sizes and different values of image add backs, while the manual technique was based on image segmentation. A comparison was then made to see how precise the two techniques are in detecting and extracting building footprints. Finally, the results were compared with manually digitized building reference data to conduct an accuracy assessment and the result shows that LIDAR data provide a better shape characterization of each buildings.

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Key Indicators for the Growth of Logistics and Distribution Tech Startups in Thailand

  • Thanatchaporn JARUWANAKUL
    • Journal of Distribution Science
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    • v.21 no.2
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    • pp.35-43
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    • 2023
  • Purpose: As Thailand seeks to become a regional startup hub, Thai startups have been acquiring growth and scalability in the last ten years. Hence, this paper examines influential factors in Thailand's growth of logistics tech startups. The conceptual framework incorporates sensing user needs, sensing technological options, conceptualizing, scaling, and stretching, co-producing, and orchestrating, business strategy, strategic flexibility, and startup growth. Research design, data, and methodology: The quantitative method was applied to distribute the questionnaire to 500 managers and above in logistics tech startups in Thailand. The sampling techniques involve judgmental, convenience, and snowball samplings. Before the data collection, The Item Objective Congruence (IOC) Index and pilot test (n=45) were employed for content validity and reliability. The data were mainly analyzed by Confirmatory Factor Analysis (CFA) and Structural Equation Model (SEM). Results: The findings revealed that sensing technological options, scaling, and stretching, co-producing, and orchestrating, and business strategy significantly influence the growth of startups in Thailand. Nevertheless, sensing user needs, conceptualizing, and strategic flexibility have no significant relationship with startup growth. Conclusions: For Thailand to accelerate its digital economy driven by tech startups, firms must emphasize influential factors to accelerate growth by providing the right tech solutions for people's lives.

Extraction of Waterline Using Low Altitude Remote Sensing (저고도 원격탐사 영상 분석을 통한 수륙경계선 추출)

  • Jung, Dawoon;Lee, Jong-Seok;Baek, Ji-Yeon;Jo, Young-Heon
    • Korean Journal of Remote Sensing
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    • v.36 no.2_2
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    • pp.337-349
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    • 2020
  • In this study, Helikite, Low Altitude Remote Sensing (LARS) platform, was used to acquire coastal images. In the obtained image, the land and water masses were divided using four types of region clustering algorithms, and then waterline was extracted using edge detection. Quantitative comparisons were not possible due to the lack of in-situ waterline data. But, based on the image of the infrared band where water masses and land are relatively clear, the waterlines extracted by each algorithm were compared. As a result, it was found that each algorithm differed significantly in the part where the distinction between water masses and land was ambiguous. This is considered to be a difference in the process of selecting the threshold value of the digital number that each algorithm uses to distinguish the regions. The extraction of waterlines through various algorithms is expected to be used in conjunction with a Low Altitude Remote Sensing system that can be continuously monitored in the future to explain the rapid changes in coastal shape through several years of long-term data from fixed areas.

3D Visualization of Satellite Remote-Sensing Images Using an Array DBMS (Array DBMS을 이용한 위성원격탐사 영상의 3차원 시각화)

  • Choi, Jong Hyeok;Lee, Jong Yun
    • Journal of Digital Convergence
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    • v.13 no.2
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    • pp.193-204
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    • 2015
  • An array DBMS has been expected widely from scientists because it is convenient to store and analyze the data of array type. In this paper, we describe how to handle satellite remote-sensing images in the array DBMS. However, previous works in their visualization have two problems as follows. First, the images are visualized as a state of distorted by the curvature of the earth. Second, it is difficult to apply the results of visualization by pre-written queries to other analyses. Therefore, this paper proposes a three dimensional visualization method of satellite remote-sensing images, not traditional 2D visualization. Our research contents are as follows. First, we describe how to store, process, and analyze the satellite remote-sensing images in the array DBMS. Second, we propose a three-dimensional visualization method for their processed outputs. Lastly, our contributions can be summarized that we propose a method of handling satellite remote-sensing images in the array DBMS and their 3D visualization techniques. It is also expected that their use be available widely in many industrial areas.