• Title/Summary/Keyword: Recovery of occlusion areas

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Patch-Based Processing and Occlusion Area Recovery for True Orthoimage Generation (정밀정사영상 생성을 위한 패치기반 처리와 폐색지역 복원)

  • Yoo, Eun-Jin;Lee, Dong-Cheon
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.28 no.1
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    • pp.83-92
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    • 2010
  • Emergence of high-resolution digital aerial cameras and airborne laser scanners have made innovative progress in photogrammetry and spatial information technology. The purpose of this study is to generate true orthoimage by recovering occlusion areas. The orthoimages were generated patch-based transformation. The occlusion areas were mutually corrected by using multiple aerial images. This study proposed a novel method of building roof based orthoimage generation and an effective method of occlusion area detection and recovery. The proposed methods could be efficient to generate true orthoimages in urban areas where occlusion areas are problematic.

RADIOMETRIC RESTORATION OF SHADOW AREAS FROM KOMPSAT-2 IMAGERY

  • Choi, Jae-Wan;Kim, Hye-Jin;Han, You-Kyung;Kim, Yong-II
    • Proceedings of the KSRS Conference
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    • 2008.10a
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    • pp.371-374
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    • 2008
  • In very high-spatial resolution remote sensing imagery, it is difficult to extract the feature information of various objects because of occlusion and shadows. Moreover, various and feeble information within shadows can be of use in GIS-based applications and remote sensing analysis. In this paper, we developed a radiometric restoration method for shadow areas using KOMPSAT-2 satellite image. After detecting the shadow, non-shadow pixels nearby are extracted using a morphological filter. An iterative linear regression method is applied to calculate the relationship between shadow and non-shadow pixels. The shadows are restored by the parameters of the linear regression algorithm. Tests show that recovery of shadowed areas by our method leads to improved image quality.

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Protective Effects of Gamiheechum-tang(Jiaweixiqian-tang) on Hypertension and Brain Damage (가미치첨탕이 고혈압 및 뇌손상에 미치는 효과)

  • Ryu, Jong-Sam;Kim, Dong-Hee;Park, Jong-O;Namgung, UK;Hong, Seok
    • The Journal of Korean Medicine
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    • v.24 no.3
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    • pp.72-83
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    • 2003
  • Objective : The goal of the present study was to investigate the protective effect of Gamiheechum-tang (Jiaweixiqian-tang; GHCT) on brain tissue damage from chemical or ischemic insults. Methods : Levels of cultured cortical neuron death caused by toxic chemicals were measured by LDH release assay. Neuroprotective effects of GHCT on brain tissues were examined in vivo by ischemic model of middle cerebral artery (MCA) occlusion. Results : Animal groups treated with GBCT showed significantly decreased hypertension, and reduced levels of aldosterone, dopamine, and epinephrine in the plasma. GHCT treatments ($l0-200\mu\textrm{g}/ml$) significantly decreased cultured cortical neuron death mediated by AMPA, kainate, BSO, or Fe2+ when measured by LDH release assay. Yet, cell death mediated by NMDA was effectively protected by GHCT at the highest concentration examined ($200\mu\textrm{g}/ml$). In the in vivo experiment examining brain damage by MCA occlusion, affected brain areas by ischemic damage and edema were significantly less in animal groups administered with GHCT compared to the non-treated control group. Neurological examinations of forelimbs and hindlimbs showed that GHCT treatment improved animals' recovery from ischemic injury. Moreover, the extent of injury in cortical and hippocampal pyramidal neurons in ischemic rats was much reduced by GHCT, whose morphological features were similarly observed in non-ischemic animals. Conclusion : The present data suggest that GBCT may play an important role in protecting brain tissues from chemical or ischemic injuries.

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Increase of Synapsin I, Phosphosynapsin (ser-9), and GAP-43 in the Rat Hippocampus after Middle Cerebral Artery Occlusion

  • Jung, Yeon-Joo;Huh, Pil-Woo;Park, Su-Jin;Park, Jung-Sun;Lee, Kyung-Eun
    • The Korean Journal of Physiology and Pharmacology
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    • v.8 no.2
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    • pp.77-81
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    • 2004
  • The loss of neurons and synaptic contacts following cerebral ischemia may lead to a synaptic plastic modification, which may contribute to the functional recovery after a brain lesion. Using synapsin I and GAP-43 as markers, we investigated the neuronal cell death and the synaptic plastic modification in the rat hippocampus of a middle cerebral artery occlusion (MCAO) model. Cresyl violet staining revealed that neuronal cell damage occurred after 2 h of MCAO, which progressed during reperfusion for 2 weeks. The immunoreactivity of synapsin I and GAP-43 was increased in the stratum lucidum in the CA3 subfield as well as in the inner and outer molecular layers of dentate gyrus in the hippocampus at reperfusion for 2 weeks. The immunoreactivity of phosphosynapsin was increased in the stratum lucidum in the CA3 subfield during reperfusion for 1 week. Our data suggest that the increase in the synapsin I and GAP-43 immunoreactivity probably mediates either the functional adaptation of the neurons through reactive synaptogenesis from the pre-existing presynaptic nerve terminals or the structural remodeling of their axonal connections in the areas with ischemic loss of target cells. Furthermore, phosphosynapsin may play some role in the synaptic plastic adaptations before or during reactive synaptogenesis after the MCAO.