• The Korean Journal of Pesticide Science
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• v.4 no.3
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• pp.47-51
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• 2000

A some of synthesized 2,3-dihydro-2,2,4,6,7-pentamethylbenzofuran-5-yl substituents in 5-benzofuryl-2-[1-(alkoxyimino)alkyl]-3-hydroxycyclohex-2-en-1-one derivatives as substrates were found to show herbicidal activity against rice plant (Oryza sativa L.) and barnyard grass (Echinochloa crus-galli) with post emergence under submerged conditions. The substrate with $R_{1}$=methyl substituents, $1{\sim}5$ showed the higher herbicidal activity to the seed, 3 leaf stage of rice plant and barnyard grass. The structure activity relationships (SARs) on the herbicidal activity of $R_{1}$ and $R_{2}$ on the azomethine bond in substrate were analysized. In the condition of $R_{1}$ groups are same, the herbicidal activity against 3 leaf stage of rice plant were governed by the optimal hydrophobicity $(logP)_{opt.}=4.57$. Whereas, in the case of barnyard grass, the herbicidal activities were largely dependent upon the steric effect, $B_{2}$ constant than hydrophobicity. In order to take the selective herbicidal activity between rice plant and barnyard grass, it is assumed that the (S) should be a round shape with higher hydrophobicity (logP>4.57) than optimal value. Also, the $R_{1}$ groups must be small and the $R_{2}$ groups are advisable to be unsaturate.

• Journal of the Korea Computer Graphics Society
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• v.25 no.3
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• pp.43-54
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• 2019

In this paper, we review the applicability of fog screen to implement 'Spatial Augmented Reality' which displays the image on the whole space of real space or in real space by separating display equipment and user, in contrast to the traditional Augmented Reality. Through three exhibitions and one performance, we confirmed t hat the fog screen, which can be passed through, is a suitable material for implementing the Spatial Augment ed Reality. We found that the hologram production was easier than before because of fog screen. Through the questionnaire survey conducted on performers along with the exhibition, we found that only about half of people know what a fog screen is, and about 10% of the total respondents saw the fog screen. In order to investigate the effect of fog screen on the surrounding space, we conducted an experiment to observe the change of humidity according to the time and distance in the Children's Culture Center of the Asian Culture Center. We found that the humidity within a radius of 5m around the fog screen could increase by 2~3%($6,400m^3$ standard). Thus we provided some safety requirement with fog screen when works made of materials vulnerable to moisture such as paint, paper, and wood are exhibited at the same time with fog screen in the exhibition hall.

• 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.

• Korean Journal of Environmental Agriculture
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• v.19 no.3
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• pp.242-246
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• 2000

This study was carried out to show the chemical variations of monthly water quality and to estimate the quality as irrigation water at Seo-Lake. The water quality was surveyed at 6 sites for 7 months from May to November in 1999. The average concentration of $COD_{Cr}$ at Seo-Lake was 47.8mg/L. This value meant that the organic matters at the lake would exceed to the crop damage level (50mg/L). Especially, the values in May and in July were 83.07mg/L, 80.64mg/L, respectively. The average concentration of $NH_3-N$ was appeared to 2.84mg/L. But it was shown 5.72mg/L in May. That could put a restraint on the productive power of the crops. It was supposed that happened by eutrophication. And the water pollutant levels were high at stagnation part of the lake. But average water quality of the lake could be used for irrigation. The result showed that the research and the management of water quality were needed to make the lake water more suitable as the source for irrigation.

• Korean Security Journal
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• no.13
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• pp.113-144
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• 2007

The entire world has lived in terror threatened by new-terrorism since the 9.11 terror. Having appeared since 9.11, new-terrorism is new kind of terror targeting victims at random. Bioterrorism is one good example. Since bioterrorism happens secretly, it's hard to identify. The case becomes even harder to detect if it takes the form of a new epidemic. This study set out to apply the four phases of crisis management regarding outbreak and measures of SARS, the latest new epidemic, and to prepare against bioterrorism taking the form of a new epidemic, It also shows the efforts to study what to prepare and what kind of actions to take in case of bioterrorism by applying the four phases. There results demonstrate that the preventive measures against bioterrorism include arranging terror-related laws and identifying and monitoring expected pathogenic organs. In the preparation phases, they should integrate the related agencies, prepare for the standard operating procedures(SOP), execute integrated training sessions among the related agencies, and secure the necessary resources such as vaccine, cures, and exploration devices. In the response phases, they need to set up a rapid diagnosis system, quarantine and then cure the patients, and pursue cooperation from the media and promotions and further an international cooperation system to take appropriate measures. And the final recovery phases should involve offering emergency support by checking the situations and engaging in activities to prevent another terror attack by providing counseling, exchanging information, and analyzing and evaluating the causes.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.10
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• pp.2997-3003
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• 2009

The pharmacological profile of KR-31081, a nonpeptide $AT_1$ selective angiotensin receptor antagonist, was investigated by receptor binding studies, functional in vitro assays with rabbit aorta. KR-31081 inhibited the specific binding of $[^{125}I]\;[Sar^1,\;Ile^8]$-angiotensin II to human recombinant $AT_1$ receptor with an 8.6-fold greater potency than losartan ($IC_{50}$: 1.43 and 12.3 nM, respectively), but it did not inhibit the binding of [$^{125}I$] CGP 42112A to human recombinant $AT_2$ receptor ($IC_{50}$: higher than $10{\mu}M$ for both). The Hill coefficient for the competition curve of KR-31081 against $AT_1$ receptor was not significantly different from unity (0.99). Scatchard analysis showed that KR-31081 interacted with human recombinant $AT_1$ receptor in a competitive manner, as with losartan. In functional studies with rabbit aorta, KR-31081 competitively inhibited the contractile response to angiotensin II ($pK_B$ values: 8.66) with 20-70% decrease in the maximum contractile responses, unlike losartan that showed competitive antagonism without any change in the maximum contractile responses to angiotensin II ($pA_2$ values: 7.59). These results suggest that KR-31081 is a highly potent $AT_1$ selective angiotensin II receptor antagonist with a mode of insurmountable antagonism to be developed as the exploratory potential of this compound.

• Natural Product Sciences
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• v.13 no.1
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• pp.33-39
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• 2007

Eleven polyhydroxyursane triterpenoids (PHUTs) were tested to determine their cytoprotective, immunosuppressive and anti-inflammatory effects. To compare the bioactivities of $19{\alpha}$-hydroxyursane-type triterpenoids {23-hydroxytormentic acid (6), its methyl ester (7), tormentic acid (8), niga-ichigoside $F_1$ (9),euscaphic acid (10) and kaji-ichigoside $F_1$ (11)} of the Rosaceae crude drugs (Rubi Fructus and Rosa rugosae Radix) with PHUTs possessing no $19{\alpha}-hydroxyl$ of Centella asiatica (Umbelliferae), the four PHUTs, asiaticoside (1), madecassoside (2), asiatic acid (3), and madecassic acid (4) were isolated from C. asiatica and 23-hydroxyursolic acid (5) from Cussonia bancoensis. Cytoprotective effects were assessed by measuring cell viabilities against cisplatin-induced cytotoxocity in $LLC-PK_1$, cells (proximal tubule, pig kidney) to determine whether these agents have protective effects against nephrotoxicity caused by cisplatin. The inhibitory effect of 11 PHUTS on nitric oxide (NO) and prostaglandin $E_2\;(PGE_2)$ were evaluated by measuring nitrite accumulation in lipopolysaccharide (LPS)-induced macrophage RAW 264.7 cells, and their anti-inflammatory effects were tested in 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced mouse ear edema model. Six MHUTs (compounds 1, 2, 4, 6, 10, and 11) exhibited higher cell viabilities during cisplatin-induced cytotoxicity testing even at a concentration of $200\;{\mu}g/ml$ than cisplatin only-treated group, suggesting that ese compounds have the potentcytoprotective efffcts. Compounds 1 and 3 of the C. asiatica and niga-ichigoside $F_1$ exhibited no inhibitory effect on NO and/or $PGE_2$ production whereas other PHUTs produced mild to significant NO and/or $PGE_2$ production.The four compounds (2, 5, 9, and 10) potently inhibited mouse ear edema induced by TPA whereas two compounds (1 and 3) had no activity in this test. These results suggest that many PHUTs are potentchemopreventives. Structure-activity relationship (SAR) was also discussed in each assay with regard to the significant role of OHs at the position of 2, 3, 6, 19, and 23 and to the glycoside linkage at the 28-carboxyl.

• Pediatric Infection and Vaccine
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• v.27 no.1
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• pp.1-10
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• 2020

A cluster of severe pneumonia of unknown etiology in Wuhan City, Hubei province in China emerged in December 2019. A novel coronavirus named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was isolated from lower respiratory tract sample as the causative agent. The current outbreak of infections with SARS-CoV-2 is termed coronavirus disease 2019 (COVID-19) by the World Health Organization (WHO). COVID-19 rapidly spread into at least 114 countries and killed more than 4,000 people by March 11, 2020. WHO officially declared COVID-19 a pandemic on March 11, 2020. There have been 2 novel coronavirus outbreaks in the past 2 decades. The outbreak of severe acute respiratory syndrome (SARS) in 2002-2003 caused by SARS-CoV had a case fatality rate of around 10% (8,098 confirmed cases and 774 deaths), while Middle East respiratory syndrome (MERS) caused by MERS-CoV killed 858 people out of a total 2,499 confirmed cases between 2012 and 2019. The purpose of this review is to summarize known-to-date information about SARS-CoV-2, transmission of SARS-CoV-2, and clinical features of COVID-19.

• Journal of Soil and Groundwater Environment
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• v.15 no.3
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• pp.44-51
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• 2010

Contamination of groundwater from point and non-point sources is one of major problems of water resource manangement in Jeju island. This study characterized groundwater and soil contamination in Hallim area which is one of the areas of significantly contaminated soil and groundwater in Jeju Island. The amount of loaded contaminant (ALC) of Jeju area was estimated as 13,212 ton N/yr and 3,210 ton P/yr, The ALC of Hallim area was amounted to 2,895 ton N/yr and 1,102 ton P/yr, which accounted for 21.9% and 34.3% of the Jeju's ALC, respectively. The soil pH values (5.6-5.9) were not much different in land use areas. By contrat, average cation exchange capacity (CEC) of 14.1 $cmol^+/kg$ was high comparing to the nationwide range of 7.7-10.9 $cmol^+/kg$. Further, Sodium adsorption ratios (SARs) of horse ranch, pasture, and cultivating land for livestock were as high as 0.19, 0.17, and 0.16 respectively, comparing to the other landuse areas. Nitrate nitrogen at 22.2% of total groundwater wells exceeded 10 mg/L (the criteria of nitrate nitrogen for drinking water), averaginged 6.62 mg/L with maximum 28.95 mg/L. Groundwater types belonged to Mg-$HCO_3$, Na-$HCO_3$, Ca-$HCO_3$, and Na-Cl, among which Mg-$HCO_3$ type occupied more than 70% of the total samples, indicating the presence of anthropogenic sources. The concentration of nitrate nitrogen was negatively related to altitude and well depth, and positively related to the concentration of Ca, Mg, and $SO_4$ which might originate from chemical fertilizer. The ratio of nitrogen isotopes was estimated as an average of 8.10$^{\circ}/_{\circ\circ}$, and the maximum value of 17.9$^{\circ}/_{\circ\circ}$. According to the nitrogen isotope ratio, the most important nitrogen source was assessed as chemical fertilizer (52.6%) followed by sewage (26.3%) and livestock manures (21.1%).

• Journal of the Korean Geographical Society
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• v.39 no.2
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• pp.212-228
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• 2004

This paper is concerned with an important aspect of regional income convergence, ${\beta}$-convergence, which refers to the negative relationship between initial income levels and income growth rates of regions over a period of time. The common research framework on ${\beta}$-convergence which is based on OLS regression models has two drawbacks. First, it ignores spatially autocorrelated residuals. Second, it does not provide any way of exploring spatial heterogeneity across regions in terms of ${\beta}$-convergence. Given that empirical studies on ${\beta}$-convergence need to be edified by spatial data analysis, this paper aims to: (1) provide a critical review of empirical studies on ${\beta}$-convergence from a spatial perspective; (2) investigate spatio-temporal income dynamics across the U.S. labor market areas for the last 30 years (1969-1999) by fitting spatial regression models and applying bivariate ESDA techniques. The major findings are as follows. First, the hypothesis of ${\beta}$-convergence was only partially evidenced, and the trend substantively varied across sub-periods. Second, a SAR model indicated that ${\beta}$-coefficient for the entire period was not significant at the 99％ confidence level, which may lead to a conclusion that there is no statistical evidence of regional income convergence in the US over the last three decades. Third, the results from bivariate ESDA techniques and a GWR model report that there was a substantive level of spatial heterogeneity in the catch-up process, and suggested possible spatial regimes. It was also observed that the sub-periods showed a substantial level of spatio-temporal heterogeneity in ${\beta}$-convergence: the catch-up scenario in a spatial sense was least pronounced during the 1980s.