• Title/Summary/Keyword: SAR

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The Study of Standardization of Temperature Distribution of Interstitial Hyperthermia -In Phantoms and Living cat's brain tissue (Normal Tissue)- (915 MHz 극초단파 자입온열시 온도분포 적정화에 관한 연구 -조직등가물 및 가묘대뇌를 대상으로-)

  • Kyoung Hwan Koh;Cho Chul Koo;Park Young Hwan;Yoo Seong Yul;Kim Jong Hyun;Lee Seung Hoon
    • Radiation Oncology Journal
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    • v.8 no.1
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    • pp.7-15
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    • 1990
  • The ultimate objective of our experiment is to obtain the precise distribution of temperature in malignant tumors occurring in cerebral parenchyme of human beings when we will carry out interstitial hyperthermia in the near future. To achieve this purpose, first of all, it is necessary to make an attempt at performing interstitial hyperthermia in vivo under the similar condition of human beings. Therefore, we chose cats as materials much alike tissue characteristics of human beings. Moreover, it is also necessary to get the basic data from dynamic phantom in order to standardize and compare results obtained from interstitial hyperthermia carried out in cats. By having performed these experiments we got the following results. 1) On doing interstitial hyperthermia with 915 MHz microwave, the possible treated volume was 2 cm by 2 cm by 6 cm according to $50\%$ specific absorption rate (SAR). 2) The distribution of temperature within non-circulated static phantom was much the same as power density in air, but we observed that the temperature, within $5\~10$ minutes, rose to more higher than $55^{\circ}C$ not measured with Ga-As fiberoptic thermistor which was not impeded by microwave after performing interstitial hyperthermia. 3) Within dynamic phantom in which normal saline was circulating, temperature reached steady state which was maintained for more than 45 minutes through transit period in 5 minutes after starting interstitial hyperthermia. 4) When we interrupted circulation in the dynamic phantom, we observed that temperature rose to the same level as in the static phantom. 5) We could carry out interstitial hyperthermia safely when we used the generating power below 5 watts. Abrupt interruption of circulation caused a rapid increase in temperature. Times taking to rise to maximum $55^{\circ}C$ were 15.2 minutes (SE 0.4),9.7 minutes (SE 0.3), and 6.3 min-utes (SE 0.4) respectively with generating powers of 5,10, and 15 watts.

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Comparative Analysis among Radar Image Filters for Flood Mapping (홍수매핑을 위한 레이더 영상 필터의 비교분석)

  • Kim, Daeseong;Jung, Hyung-Sup;Baek, Wonkyung
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.34 no.1
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    • pp.43-52
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    • 2016
  • Due to the characteristics of microwave signals, Radar satellite image has been used for flood detection without weather and time influence. The more methods of flood detection were developed, the more detection rate of flood area has been increased. Since flood causes a lot of damages, flooded area should be distinguished from non flooded area. Also, the detection of flood area should be accurate. Therefore, not only image resolution but also the filtering process is critical to minimize resolution degradation. Although a resolution of radar images become better as technology develops, there were a limited focused on a highly suitable filtering methods for flood detection. Thus, the purpose of this study is to find out the most appropriate filtering method for flood detection by comparing three filtering methods: Lee filter, Frost filter and NL-means filter. Therefore, to compare the filters to detect floods, each filters are applied to the radar image. Comparison was drawn among filtered images. Then, the flood map, results of filtered images are compared in that order. As a result, Frost and NL-means filter are more effective in removing the speckle noise compared to Lee filter. In case of Frost filter, resolution degradation occurred severly during removal of the noise. In case of NL-means filter, shadow effect which could be one of the main reasons that causes false detection were not eliminated comparing to other filters. Nevertheless, result of NL-means filter shows the best detection rate because the number of shadow pixels is relatively low in entire image. Kappa coefficient is scored 0.81 for NL-means filtered image and 0.55, 0.64 and 0.74 follows for non filtered image, Lee filtered image and Frost filtered image respectively. Also, in the process of NL-means filter, speckle noise could be removed without resolution degradation. Accordingly, flooded area could be distinguished effectively from other area in NL-means filtered image.

Anti-inflammatory Metabolites of Agrimonia pilosa Ledeb. and Their Mechanism

  • Park, Mi Jin;Ryu, Da Hye;Cho, Jwa Yeoung;Kang, Young-Hwa
    • Proceedings of the Plant Resources Society of Korea Conference
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    • 2018.04a
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    • pp.13-13
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    • 2018
  • The anti-inflammatory (INF) compounds (1-15) were isolated from Agrimonia pilosa Ledeb. (APL) by activity-guided isolation technique. The isolated compounds (1-15) were identified as quercetin-7-O-rhanmoside (1), apigenin-7-O-glycoside (2), kaempferol-7-O-glycoside (3), apigenin-7-O-[6"-(butyl)-glycoside] (4), querceitn (5), kaempferol (6), apigenin (7), apigenin-7-O-[6"-(pentyl)-glycoside] (8), agrimonolide (9), agrimonolide-6-O-glucoside (10), desmethylagrimonolide (11), desmethylagrimonolide-6-O-glucoside (12), luteolin (13), vitexin (14) and isovitexin (15). Flavonoids, compound 2, 3, 11, and 14-15 have been found in APL for the first time. Furthermore, two novel flavone derivatives, compound 4 and 8, have been isolated inceptively in plant. In the no cytotoxicity concentration ranges of $0-20{\mu}M$, nitric oxide (NO) production level of 1-15 was estimated in LPS-treated Raw 264.7 macrophage cells. The flavone aglycones, 7 (apigenin, $IC_{50}=3.69{\pm}0.34{\mu}M$), 13 (luteolin, $IC_{50}=4.62{\pm}0.43{\mu}M$), 6 (kaempferol, $IC_{50}=14.43{\pm}0.23{\mu}M$) and 5 (quercetin, $IC_{50}=19.50{\pm}1.71{\mu}M$), exhibited excellent NO inhibitory (NOI) activity in dose-dependent manner. In the structure activity relationship (SAR) study of apigenin-derivatives (APD), apigenin; Api, apigenin-7-O-glucoside; Api-G, apignenin-7-O-[6"-(butyl)-glycoside]; Api-BG and apignenin-7-O-[6"-(pentyl)-glycoside]; Api-P, from APL on INF activity was investigated. The INF mediators level such as NO, INF-cytokines, NF-KB proteins, iNOS and COX-2 were sharply increased in Raw 264.7 cells by LPS. When pretreatment with APD in INF induced macrophages, NOI activity of Api was most effective than other APD with $IC_{50}$ values of $3.69{\pm}0.77{\mu}M$. And the NOI activity was declined in the following order: Api-BG ($IC_{50}=8.91{\pm}1.18{\mu}M$), Api-PG ($IC_{50}=13.52{\pm}0.85{\mu}M$) and API-G ($IC_{50}=17.30{\pm}0.66{\mu}M$). The NOI activity of two novel compounds, Api-PG and Api-BG were lower than their aglycone; Api, but more effective than Api-G (NOI: Api-PG and Api-BG). And their suppression ability on INF cytokines such as $TNF-{\alpha}$, $IL-1{\beta}$ and IL-6 mRNA showed the similar tendency. Therefore, the anti-INF mechanism study of Api-PG and Api-BG on nuclear factor-kappa B ($NF-{\kappa}B$) pathway, representative INF mechanism, was investigated and Api was used as positive control. Api-BF was more effectively prevent the than phosphorylation of $pI{\kappa}B$ kinase (p-IKK) and p65 than Api-PG in Raw 264.7 cells. In contrast, Api-PG and Api-BG were not reduced the phosphorylation of inhibitor of kappa B alpha ($I{\kappa}B{\alpha}$). Moreover, pretreatment with Api-PG and Api-BG, dose-dependently inhibited LPS-induced expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) mRNAs and proteins in macrophage cells, and their expression were correlated with their NOI activity. Therefore, APL can be utilized to health promote agent associated with their AIN metabolites.

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DEM Generation over Coastal Area using ALOS PALSAR Data - Focus on Coherence and Height Ambiguity - (ALOS PALSAR 자료를 이용한 연안지역의 DEM 생성 - 긴밀도와 고도 민감도 분석을 중심으로 -)

  • Choi, Jung-Hyun;Lee, Chang-Wook;Won, Joong-Sun
    • Korean Journal of Remote Sensing
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    • v.23 no.6
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    • pp.559-566
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    • 2007
  • The generation of precise digital elevation model (DEM) is very important in coastal area where time series are especially required. Although a LIDAR system is useful in coastal regions, it is not yet popular in Korea mainly because of its high surveying cost and national security reasons. Recently, precise DEM has been made using radar interferometry and waterline methods. One of these methods, spaceborne imaging radar interferometry has been widely used to measure the topography and deformation of the Earth. We acquired ALOS PALSAR FBD mode (Fine Beam Dual) data for evaluating the quality of interferograms and their coherency. We attempted to construct DEM using ALOS PALSAR pairs - One pair is 2007/05/22 and 2007/08/22, another pair is 2007/08/22 and 2007/10/22 with respective perpendicular baseline of 820 m, 312m and respective height sensitivity of 75 m and 185m at southern of Ganghwa tidal flat, Siwha- and Hwaong-lake over west coastal of Korea peninsula. Ganghwa tidal flat has low coherence between 0.3 and 0.5 of 2007/05/22 and 2007/08/22 pair. However, Siwha-lake and Hwaong-lake areas have a higher coherence value (From 0.7 and 0.9) than Ganghwa tidal area. The reason of difference coherence value is tidal condition between tidal flat area (Ganghwa) and reclaimed zone (Siwha-lake and Hwaong-lake). Therefore, DEM was constructed by ALOS PALSAR pair over Siwha-lake and Hwaong-lake. If the temporal baseline is enough short to maintain the coherent phases and height sensitivity is enough small, we will be able to successfully construct a precise DEM over coastal area. From now on, more ALOS PALSAR data will be needed to construct precise DEM of West Coast of Korea peninsular.

A Study on the clarification of the name of Anapji(雁鴨池) and Anapbupyeong(雁鴨浮萍) - Focusing on Anapji through its Appearance in Poems(題詠詩) ('안압지'의 이름과 '안압부평(雁鴨浮萍)'의 의미 연구 - 안압지(雁鴨池) 제영시(題詠詩)를 중심으로 -)

  • Kang, seog-keun
    • (The)Study of the Eastern Classic
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    • no.68
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    • pp.145-171
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    • 2017
  • This study aims to clarify the meaning of the Anapji which was one of the scenic places of historical interest during Silla Dynasty and of the Anapbupyeong(雁鴨浮萍) which was one of the greatest seven miracles (Dong-do-chil-gue(東都七怪) through appearance of the Anapji in poems. Anapji lies its original meanings on Anhaji(安夏池) and then it was shortened to Anji(雁池), apji(鴨池) while Dongho(東湖) has also been called since it is located in the South of Gyeongju. As of July 2011, the Ministry of Culture officially renamed Anapji and Imhaejeon Hall Site(臨海殿址) as the palace of Crown Prince-Gyonegju Donggung(慶州 東宮) and Wolji(月池) (Historical Site No. 18) and Wolji became the current name. While pond was made during Munmu of Silla, the name Anapji did not exist. Kim Si-Seup (1465~1471) in the early Chosun period referred to the pond as Anhaji(安夏池) and its name started being called as Anapji in the Geography of Korea (Sinjeung dongguk yeoji seungnam,(新增東國輿地勝覽)(Jungjong 25, 1530). Though modern scholar states that it was being called Anapji since there are always many ducks and wild geese in the pond, they fails to present the literature evidences. The author found the line in the poem -Anapji composed by writer Kim Chul Woo, which means that a wild duck and water bird get in and off the pond on their own and the record saying which means Dong-ho(東湖) from the phrase of Dongho-saw-sar-gi(東湖書社記) of Lee Su In(李樹仁)(1739-1822)-Confucian Scholar of Gyeongju was created due to the fact that many wild geese and ducks are flying over. Based on the facts foresaid, the literature evidences for the name of Anapji are presented in the paper. Anapji is a combined word between the Anapbupyeong(雁鴨浮萍) which is a flooding weed and Dong-do-chil-gue(東都七怪). Dong-do-chil-gue is an ancient form of Modern Eight Scenic Views. Eight Scenic Views -Gyeongju Parlgyong is just well-known as scenic places without grotesque elements Dong-do-chil-gue had before. However, the author also found the passage of Ilseongnok: Records of Daily Reflections saying that Anapji has a clod that is as wide as rock(盤石) and the clod also has moneywort on, which are undulating in the wind and clarified how the Anapbupyeong became one of the one of the greatest-seven miracles Dong-do-chil-gue and why the Anapbupyeong frequently appears in the poems of many writers.