• Title/Summary/Keyword: high-spatial resolution

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Building DSMs Generation Integrating Three Line Scanner (TLS) and LiDAR

  • Suh, Yong-Cheol;Nakagawa , Masafumi
    • Korean Journal of Remote Sensing
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    • v.21 no.3
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    • pp.229-242
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    • 2005
  • Photogrammetry is a current method of GIS data acquisition. However, as a matter of fact, a large manpower and expenditure for making detailed 3D spatial information is required especially in urban areas where various buildings exist. There are no photogrammetric systems which can automate a process of spatial information acquisition completely. On the other hand, LiDAR has high potential of automating 3D spatial data acquisition because it can directly measure 3D coordinates of objects, but it is rather difficult to recognize the object with only LiDAR data, for its low resolution at this moment. With this background, we believe that it is very advantageous to integrate LiDAR data and stereo CCD images for more efficient and automated acquisition of the 3D spatial data with higher resolution. In this research, the automatic urban object recognition methodology was proposed by integrating ultra highresolution stereo images and LiDAR data. Moreover, a method to enable more reliable and detailed stereo matching method for CCD images was examined by using LiDAR data as an initial 3D data to determine the search range and to detect possibility of occlusions. Finally, intellectual DSMs, which were identified urban features with high resolution, were generated with high speed processing.

Numerical Study on the Impact of the Spatial Resolution of Wind Map in the Korean Peninsula on the Accuracy of Wind Energy Resources Estimation (한반도 풍력 자원 지도의 공간 해상도가 풍력자원 예측 정확도에 미치는 영향에 관한 수치연구)

  • Lee, Soon-Hwan;Lee, Hwa-Woon;Kim, Dong-Hyuk;Kim, Min-Jung;Kim, Hyun-Goo
    • Journal of Environmental Science International
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    • v.18 no.8
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    • pp.885-897
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    • 2009
  • In order to make sure the impact of spatial resolution of wind energy map on the estimation of wind power density in the Korean Peninsula, the comparison studies on the characteristics of wind energy map with three different spatial resolutions were carried out. Numerical model used in the establishment of wind map is MM5 (5th generation Mesoscale Model) with RBAPS (Regional Data Assimilation and Prediction System) as initial and boundary data. Analyzed Period are four months (March, August, October, and December), which are representative of four seasons. Since high spatial resolution of wind map make the undulation of topography be clear, wind pattern in high resolution wind map is correspond well with topography pattern and maximum value of wind speed is also increase. Indication of island and mountains in wind energy map depends on the its spatial resolution, so wind patterns in Heuksan island and Jiri mountains are clearly different in high and low resolutions. And area averaged power density can be changed by estimation method of wind speed for unit area in the numerical model and by treatment of air density. Therefore the studiable resolution for the topography should be evaluated and set before the estimation of wind resources in the Korean Peninsula.

An Efficient Focusing Method for High Resolution Ultrasound Imaging

  • Kim Kang-Sik
    • Journal of Biomedical Engineering Research
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    • v.27 no.1
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    • pp.22-29
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    • 2006
  • This paper proposes an efficient array beamforming method using spatial matched filtering for ultrasound imaging. In the proposed method, ultrasound waves are transmitted from an array subaperture with fixed transmit focus as in conventional array imaging. At receive, radio frequency (RF) echo signals from each receive channel are passed through a spatial matched filter that is constructed based on the system transmit-receive spatial impulse response. The filtered echo signals are then summed. The filter remaps and spatially registers the acoustic energy from each element so that the pulse-echo impulse response of the summed output is focused with acceptably low side lobes. Analytical beam pattern analysis and simulation results using a linear array show that the proposed spatial filtering method can provide more improved spatial resolution and contrast-to-noise ratio (CNR) compared with conventional dynamic receive focusing (DRF) method by implementing two-way dynamically focused beam pattern throughout the field.

Spatial Resolution and Dynamic Range Enhancement Algorithm using Multiple Exposures (복수 노출을 이용한 공간 해상도와 다이내믹 레인지 향상 알고리즘)

  • Choi, Jong-Seong;Han, Young-Seok;Kang, Moon-Gi
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.45 no.6
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    • pp.117-124
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    • 2008
  • The approaches to overcome the limited spatial resolution and the limited dynamic range of image sensors have been studied independently. A high resolution image is reconstructed from multiple low resolution observations and a wide dynamic range image is reconstructed from differently exposed multiple low dynamic range in es based on signal processing approach. In practical situations, it is reasonable to address them in a unified context because the recorded image suffers from limitations of both spatial resolution and dynamic range. In this paper, the image acquisition process including limited spatial resolution and limited dynamic range is modelled. With the image acquisition model, the response function of the imaging system is estimated and the single image of which spatial resolution and dynamic range are simultaneously enhanced is obtained. Experimental results indicate that the proposed algorithm outperforms the conventional approaches that perform the high resolution and wide dynamic range reconstruction sequentially with respect to both objective and subjective criteria.

Quantitative Evaluation of Super-resolution Drone Images Generated Using Deep Learning (딥러닝을 이용하여 생성한 초해상화 드론 영상의 정량적 평가)

  • Seo, Hong-Deok;So, Hyeong-Yoon;Kim, Eui-Myoung
    • Journal of Cadastre & Land InformatiX
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    • v.53 no.2
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    • pp.5-18
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    • 2023
  • As the development of drones and sensors accelerates, new services and values are created by fusing data acquired from various sensors mounted on drone. However, the construction of spatial information through data fusion is mainly constructed depending on the image, and the quality of data is determined according to the specification and performance of the hardware. In addition, it is difficult to utilize it in the actual field because expensive equipment is required to construct spatial information of high-quality. In this study, super-resolution was performed by applying deep learning to low-resolution images acquired through RGB and THM cameras mounted on a drone, and quantitative evaluation and feature point extraction were performed on the generated high-resolution images. As a result of the experiment, the high-resolution image generated by super-resolution was maintained the characteristics of the original image, and as the resolution was improved, more features could be extracted compared to the original image. Therefore, when generating a high-resolution image by applying a low-resolution image to an super-resolution deep learning model, it is judged to be a new method to construct spatial information of high-quality without being restricted by hardware.

GENERATION OF FOREST FRACTION MAP WITH MODIS IMAGES USING ENDMEMBER EXTRACTED FROM HIGH RESOLUTION IMAGE

  • Kim, Tae-Geun;Lee, Kyu-Sung
    • Proceedings of the KSRS Conference
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    • 2007.10a
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    • pp.468-470
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    • 2007
  • This paper is to present an approach for generating coarse resolution (MODIS data) fraction images of forested region in Korea peninsula using forest type area fraction derived from high resolution data (ASTER data) in regional forest area. A 15-m spatial resolution multi-spectral ASTER image was acquired under clear sky conditions on September 22, 2003 over the forested area near Seoul, Korea and was used to select each end-member that represent a pure reflectance of component of forest such as different forest, bare soil and water. The area fraction of selected each end-member and a 500-m spatial resolution MODIS reflectance product covering study area was applied to a linear mixture inversion model for calculating the fraction image of forest component across the South Korea. We found that the area fraction values of each end-member observed from high resolution image data could be used to separate forest cover in low resolution image data.

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Development of Diode Based High Energy X-ray Spatial Dose Distribution Measuring Device

  • Lee, Jeonghee;Kim, Ikhyun;Park, Jong-Won;Lim, Yong-Kon;Moon, Myungkook;Lee, Sangheon;Lim, Chang Hwy
    • Journal of Radiation Protection and Research
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    • v.43 no.3
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    • pp.97-106
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    • 2018
  • Background: A cargo container scanner using a high-energy X-ray generates a fan beam X-ray to acquire a transmitted image. Because the generated X-rays by LINAC may affect the image quality and radiation protection of the system, it is necessary to acquire accurate information about the generated X-ray beam distribution. In this paper, a diode-based multi-channel spatial dose measuring device for measuring the X-ray dose distribution developed for measuring the high energy X-ray beam distribution of the container scanner is described. Materials and Methods: The developed high-energy X-ray spatial dose distribution measuring device can measure the spatial distribution of X-rays using 128 diode-based X-ray sensors. And precise measurement of the beam distribution is possible through automatic positioning in the vertical and horizontal directions. The response characteristics of the measurement system were evaluated by comparing the signal gain difference of each pixel, response linearity according to X-ray incident dose change, evaluation of resolution, and measurement of two-dimensional spatial beam distribution. Results and Discussion: As a result, it was found that the difference between the maximum value and the minimum value of the response signal according to the incident position showed a difference of about 10%, and the response signal was linearly increased. And it has been confirmed that high-resolution and two-dimensional measurements are possible. Conclusion: The developed X-ray spatial dose measuring device was evaluated as suitable for dose measurement of high energy X-ray through confirmation of linearity of response signal, spatial uniformity, high resolution measuring ability and ability to measure spatial dose. We will perform precise measurement of the X-ray beamline in the container scanning system using the X-ray spatial dose distribution measuring device developed through this research.

A STUDY ON THE DETERMINATION OF THE INSTANTANEOUS FIELD OF VIEW FOR I-M HIGH RESOLUTION SATELLITE IMAGE

  • Seo Doo-Chun;Park Su-Young;Lee Dong-Han;Lee Sun-Gu;Song Jeong Heon;Lim Hyo-Suk
    • Proceedings of the KSRS Conference
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    • 2005.10a
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    • pp.649-652
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    • 2005
  • In this paper we present a detail approach of the determination of IFOV (Instantaneous Field of View) of high-resolution (l m) panchromatic satellite image over test site. IFOV is the representative measurements as the determination of the spatial resolution in remote sensed imaging system. It can be defined as some area on the ground with the particular altitude when the satellite acquires the image at any given time. Especially, spatial resolution of passive sensors primarily depends on their IFOV. The determination of IFOV goes through simple steps of procedure as followings: Firstly, the GSD (Ground Sample Distance) should be computed at each point on the geometrically corrected image. Then, The GSD is converted into the IFOV. So we are going to explain our test procedures and results.

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A Study on Super Resolution Image Reconstruction for Effective Spatial Identification

  • Park Jae-Min;Jung Jae-Seung;Kim Byung-Guk
    • Spatial Information Research
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    • v.13 no.4 s.35
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    • pp.345-354
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    • 2005
  • Super resolution image reconstruction method refers to image processing algorithms that produce a high resolution(HR) image from observed several low resolution(LR) images of the same scene. This method has proven to be useful in many practical cases where multiple frames of the same scene can be obtained, such as satellite imaging, video surveillance, video enhancement and restoration, digital mosaicking, and medical imaging. In this paper, we applied the super resolution reconstruction method in spatial domain to video sequences. Test images are adjacently sampled images from continuous video sequences and are overlapped at high rate. We constructed the observation model between the HR images and LR images applied with the Maximum A Posteriori(MAP) reconstruction method which is one of the major methods in the super resolution grid construction. Based on the MAP method, we reconstructed high resolution images from low resolution images and compared the results with those from other known interpolation methods.

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