• Korean Journal of Remote Sensing
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• v.39 no.5_1
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• pp.495-505
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• 2023

The Musan mine, situated in Musan County, Hamgyong Province, North Korea, stands as a prominent open-pit iron mine on the Korean Peninsula. This study focuses on estimating the mining and dumping activities within the Musan mine area by analyzing digital elevation model (DEM) changes. To calculate the long-term volume changes in the Musan mine, we digitized and converted the 1:200,000-scale third topographic map of the Joseon published in 1918 and compared with interferometric synthetic aperture radar (InSAR) DEMs, including Shuttle Radar Topography Mission DEM (2000) and Copernicus DEM (2011-2015). The findings reveal that over a century, Musan mine yielded around 1.37 billion tons of iron ore, while approximately 1.06 billion tons of waste rock were dumped. This study is particularly significant as it utilizes a historical topographic map predating the full-scale development of Musan mine to estimate a century's mining production and waste rock deposition. It is expected that this research provides valuable insights for future investigation of surface change of North Korea where the acquisition of in situ data remains challenging.

• The Korean Journal of Air & Space Law and Policy
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• v.18
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• pp.135-183
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• 2003

Aerospace force is a determining factor in a modem war. The combat field is expanding to space. Thus, the legitimacy of establishing aerospace force is no longer an debating issue, but "how should we establish aerospace force" has become an issue to the military. The standard limiting on the military use of space should be non-aggressive use as asserted by the U.S., rather than non-military use as asserted by the former Soviet Union. The former Soviet Union's argument is not even strongly supported by the current Russia government, and realistically is hard to be applied. Thus, the multi-purpose satellite used for military surveillance or a commercial satellite employed for military communication are allowed under the U.S. principle of peaceful use of space. In this regard, Air Force may be free to develop a military surveillance satellite and a communication satellite with civilian research institute. Although MTCR, entered into with the U.S., restricts the development of space-launching vehicle for the export purpose, the development of space-launching vehicle by the Korea Air Force or Korea Aerospace Research Institute is beyond the scope of application of MTCR, and Air Force may just operate a satellite in the orbit for the military purpose. The primary task for multi-purpose satellite is a remote sensing; SAR sensor with high resolution is mainly employed for military use. Therefore, a system that enables Air Force, the Korea Aerospace Research Institute, and Agency for Defense Development to conduct joint-research and development should be instituted. U.S. Air Force has dismantled its own space-launching vehicle step by step, and, instead, has increased using private space launching vehicle. In addition, Military communication has been operated separately from civil communication services or broadcasting services due to the special circumstances unique to the military setting. However, joint-operation of communication facility by the military and civil users is preferred because this reduces financial burden resulting from separate operation of military satellite. During the Gulf War, U.S. armed forces employed commercial satellites for its military communication. Korea's participation in space technology research is a little bit behind in time, considering its economic scale. In terms of budget, Korea is to spend 5 trillion won for 15 years for the space activities. However, Japan has 2 trillion won annul budget for the same activities. Because the development of space industry during initial fostering period does not apply to profit-making business, government supports are inevitable. All space development programs of other foreign countries are entirely supported by each government, and, only recently, private industry started participating in limited area such as a communication satellite and broadcasting satellite, Particularly, Korea's space industry is in an infant stage, which largely demands government supports. Government support should be in the form of investment or financial contribution, rather than in the form of loan or borrowing. Compared to other advanced countries in space industry, Korea needs more budget and professional research staff. Naturally, for the efficient and systemic space development and for the prevention of overlapping and distraction of power, it is necessary to enact space-related statutes, which would provide dear vision for the Korea space development. Furthermore, the fact that a variety of departments are running their own space development program requires a centralized and single space-industry development system. Prior to discussing how to coordinate or integrate space programs between Agency for Defense Development and the Korea Aerospace Research Institute, it is a prerequisite to establish, namely, "Space Operations Center"in the Air Force, which would determine policy and strategy in operating space forces. For the establishment of "Space Operations Center," policy determinations by the Ministry of National Defense and the Joint Chief of Staff are required. Especially, space surveillance system through using a military surveillance satellite and communication satellite, which would lay foundation for independent defense, shall be established with reference to Japan's space force plan. In order to resolve issues related to MTCR, Air Force would use space-launching vehicle of the Korea Aerospace Research Institute. Moreover, defense budge should be appropriated for using multi-purpose satellite and communication satellite. The Ministry of National Defense needs to appropriate 2.5 trillion won budget for space operations, which amounts to Japan's surveillance satellite operating budges.

• Journal of the Korean Institute of Landscape Architecture
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• v.43 no.3
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• pp.77-91
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• 2015

This study aims to suggest adequate soil management through the analysis of physicochemical properties of soil in the planting grounds of Incheon International Airport, which was constructed on a massive land reclamation site. Study areas were 5 sites at the international business complex, the passenger terminal, the airport support complex, the free trade zone, and the access road. Soil profile analysis showed that 9 plots out of the 27 plots were hardpan and heterospere within 80cm from the soil surface. The earth laid on the ground was categorized as gravel based soil(4 plots), dredged soil from the sea bottom and mixed reclamation materials(2 plots), clay with poor permeability(3 plots) and waste construction material(1 plot). Average soil hardness was $11.5kg/cm^2$ and soil textures were sandy soil, sandy loam and loamy sand. Average soil pH was 6.7 and average organic matter content was 0.7%. Electrical conductivity was 0.0dS/m and exchangeable cation concentrations were $Ca^{2+}$ 3.4cmol/kg, $Mg^{2+}$ 1.5cmol/kg, $K^+$ 0.3cmol/kg and $Na^+$ 1.0cmol/kg. Average cation exchange capacity was 11.0cmol/kg. Although average figures in Solum mostly meet the landscape design criteria, properties of each soil layer showed various values sometimes over the limit. Base saturations were $Ca^{2+}$ 29.9%, $Mg^{2+}$ 13.3% and $K^+$ 3.7% for lower soil, $Ca^{2+}$ 33.3%, $Mg^{2+}$ 17.0% and $K^+$ 2.7% for mid-soil and $Ca^{2+}$ 32.6%, $Mg^{2+}$ 12.2% and $K^+$ 1.9% for upper soil. Exchangeable sodium percentages were 16.4% for lower soil, 7.5% for mid-soil and 4.7% upper soil. Sodium adsorption rates were 0.8 for lower soil, 0.3 for mid-soil and 0.2 for upper soil. Factors affecting to the vegetation growth were heterogeneity and poorness of solum, disturbance of dredged soils, high soil hardness including hardpan in the subsurface soil layer and shallow effective soil depth, high soil acidity, imbalance of base contents, low organic matter content and low available phosphate levels in the soil.

• Korean Journal of Remote Sensing
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• v.36 no.5_3
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• pp.1109-1123
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• 2020

In South Korea with forest as a major land cover class (over 60% of the country), many wildfires occur every year. Wildfires weaken the shear strength of the soil, forming a layer of soil that is vulnerable to landslides. It is important to identify the severity of a wildfire as well as the burned area to sustainably manage the forest. Although satellite remote sensing has been widely used to map wildfire severity, it is often difficult to determine the severity using only the temporal change of satellite-derived indices such as Normalized Difference Vegetation Index (NDVI) and Normalized Burn Ratio (NBR). In this study, we proposed an approach for determining wildfire severity based on machine learning through the synergistic use of Sentinel-1A Synthetic Aperture Radar-C data and Sentinel-2A Multi Spectral Instrument data. Three wildfire cases-Samcheok in May 2017, Gangreung·Donghae in April 2019, and Gosung·Sokcho in April 2019-were used for developing wildfire severity mapping models with three machine learning algorithms (i.e., Random Forest, Logistic Regression, and Support Vector Machine). The results showed that the random forest model yielded the best performance, resulting in an overall accuracy of 82.3%. The cross-site validation to examine the spatiotemporal transferability of the machine learning models showed that the models were highly sensitive to temporal differences between the training and validation sites, especially in the early growing season. This implies that a more robust model with high spatiotemporal transferability can be developed when more wildfire cases with different seasons and areas are added in the future.

• 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.

• 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.

• 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.

• 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.

• (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.