• Journal of the Korean Society of Radiology
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• v.11 no.1
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• pp.49-54
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• 2017

As the Radiofrequency(RF) increases with the magnetic field strength, the wavelength of the RF excitation field becomes smaller, which leads to more the thermal effect in the human-body placed in the electric field. MRI scanner used was GE signa 1.5T, HDx 3.0T and Philips 3.0T with same routine clinical sequence protocol. Therefore temperature was measured before and after each scan. Taken the temperatures in the ear with ear infra-red type thermometer(Braun co). 3.0T were temperature increases more than $0.15^{\circ}C$ and GE 3.0T MRI equipment about $0.14^{\circ}C$ higher than the Philips 3.0T MRI(p<0.012). Psychogenic status was investigated by the survey respondents about their status can not just answer therefore, a little different from the expected. In our study of Thermal effect of clinical MRI with clinical protocol sequence, we found that the 3.0T in the body-temperature rise was greater than the 1.5T. Therefore, in clinical 3.0T examine the dangerous situation caused by the temperature rise occurred (burns, impaired thermoregulatory mechanism in patients with high-temperature damage, exhaustion occurs due to excessive sweating), not to appear the more watched the patient's condition with procedure.

• 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%).

• Analytical Science and Technology
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• v.25 no.5
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• pp.324-332
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• 2012

Construction era of Pungnabtoseong earthen wall is one of the most popular controversial issues in Korean archaeological research. For the evaluation of construction era, OSL dating was carried out using seven pottery pieces collected in each construction stage. From TL/OSL characteristics, and the results of absolute zeroing test and recovery test, it was proved that the pottery samples were completely bleached. The reliable paleodose was evaluated by using the SAR method with preheat at $220^{\circ}C$, and the pottery OSL age was determined from the ratio of paleodose to annual dose rate. Considering the resultant OSL ages, archaeological context and the related 14C ages, the first construction era was determined as $294{\pm}52$ yrs AD ($1{\sigma}$ SE). Also we found that the enlargement of construction stage III was $328{\pm}30$ yrs AD ($1{\sigma}$ SE) and final construction was finished within $400{\pm}76$ yrs AD ($1{\sigma}$ SE). Therefore, it is suggested that the construction of Pungnabtoseong earthen wall was firstly started in the late $3^{rd}$ century AD and several enlargements and repairs had been carried out, before the transfer of the capital of Baekje dynasty to Woongjin (Gongju) at 475 AD.

• Korean Journal of Environmental Agriculture
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• v.2 no.2
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• pp.78-82
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• 1983

Some physico-chemical properties and heavy metal contents of up-land and paddy field soils on the drainage-basin of Daejeon Cheon and Yoodeung Cheon in Daejeon area were investigated. The average contents (and the range) of Pb was 6.75 ppm (2.33-11.65 ppm), Cr; 1.77 ppm (0.58-4.0 ppm), Cd; 0.7pprn (0.09-1.83 ppm), Cu; 9.96 ppm (t-19.36 ppm), and Zn; 19.99 ppm (2.38-47.9 ppm) in up-land soil, and Pb; 7.77 ppm (t-15.5 ppm), Cr; 1.91 ppm (t-9.38 ppm), Cd; 0.21 ppm(t-2.05 ppm), Cu; 11.17 ppm (t-21.96 ppm), and Zn; 18.0l ppm (1.65-40.0ppm) in paddy field soil, respectively.

• Journal of Life Science
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• v.20 no.6
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• pp.831-837
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• 2010

KR-31125 (2-butyl-5-dimethoxymethyl-6-phenyl-7-methyl-3-[[2'-(1H-tetrazol-5-yl)biphenyl-4-yl]methyl]-3H-imidazo[4,5-b]pyridine) is a potent inhibitor of angiotensin II type 1 ($AT_1$) receptors in human recombinant $AT_1$ receptors and rabbit aorta. These in vitro studies revealed that KR-31125 inhibited specific [$^{125}I$] [$Sar^1$, $Ile^8$]-angiotensin II binding to human recombinant $AT_1$ receptors in a concentration dependent manner with an $IC_{50}$ value of $19.72{\pm}2.65$ nM. However, no interaction with $AT_2$ receptors was detected as displayed by the competition binding of [$^{125}I$] CGP 42112A to human recombinant $AT_2$ receptor. The binding action was also confirmed as a competitive mode that was identical to the previously studied compound, losartan. In addition, KR-31125 caused a nonparallel shift to the right in the concentration response curves to angiotensin II with a 30-80% decrease in the maximum contractile responses ($pK_B$: 7.63). Compared to the previous studies with losartan that showed a parallel right shift in the maximum contractile responses to AII ($pA_2$: 7.59), KR-31125 presented a different mode of action with a similar potency to losartan. These results demonstrate that KR-31125 is a highly potent and $AT_1$ selective angiotensin II receptor antagonist that can be applied to the fields of new diagnostic and research tools with upcoming in vivo study results.

• Management & Information Systems Review
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• v.36 no.2
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• pp.81-92
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• 2017

This study was to investigate the elasticity in tourism demand of Chinese tourists visiting Malaysia through ARDL models by using Chinese tourists arrivals, GDP, CPI, transportation costs and others. When China was implementing an open-door policy with foreign countries in the early 15th century, the movement of Chinese was very limited, and then communication between China and other countries was very weak. However, the Chinese government persistently and entirely implemented an open-door policy by participating in the World Trade Organization(WTO) in 2001. The Chinese government has opened the economy through foreign direct investment by providing various incentives for foreign investment. As a result, inbound and outbound Chinese movements increased in the early 21st century. China was one of the top five most visited tourist destinations in the world by 2016, and also Chinese tourists traveling abroad increased, so they made Malaysia a popular tourists destination because of increase sharply to around 1.41 million. This study examined the significance of major economic factors affecting the increase in Chinese tourists arriving in Malaysia. Other factors that induced their arrival included income, tourism prices, transportation costs and promotional activities. Short-run shocks from the Asian economic crisis and the outbreak of SARS were included to understand how tourism demand in Malaysia was affected. Finally this study found that the combination of the ARDL and the Error Correction Model were useful to statistically estimate the elasticities of tourism demand.

• Journal of the Korean Society of Food Science and Nutrition
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• v.21 no.2
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• pp.154-162
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• 1992

This study was designed to investigate the antitumor effect and immunological activities of chitosan extracted from Solenocera prominetis toward on mire bearing sarcoma-180. The growth inhibition ratio of the chitosan toward sarcoma-180 showed at the highest level of 63.84% when chitosan were administrated at the concentration of 40mg/kg. The direct cytotoxic effect of chitosan was not observed in the mice bearing sar-roma-180 in vitro. In the effect of immunological activities, dose-dependent responses indicated by the increase of leucocyte, peritoneal exudate cell than that of control group when chitosan administered to the mice in the concentation of 30mg/kg and 40mg/kg. Also dose-dependent responses showed also by the increase of immunoorgans weights such as body weight, liver, spleen or thymus in the same concentration of 30mg/kg and 40mg/kg. Food pad swelling having the relationship with arthus reaction of antibody-mediated hypersensitivity and delayed type hypersensitivity was recovered the almost normal level. In the efforts of macrophge on phagocytes, there were not substantial differences in phagorytic and corrected phagocytic index. In the number of plaque forming cell(PFC), PFC on the 10$^{7}$ spleen cells were increased the levels of 18.88% and 31.83% when chitosan were adminstersd at the concentration of 30mg/kg and 40mg/kg.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.44 no.9
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• pp.796-805
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• 2016

As a part of the first stage in the helicopter flight simulator development, this study numerically evaluates handling qualities of the dynamics model. The flight dynamics model was generated using public information for AS365 N2, the target aircraft of the simulator. The flight simulator is under development as a pilot training and research tool for firefighting missions. The assessment of the model intends to validate general characteristics and suitability before the model is enhanced with flight test data. The evaluation is based on the ADS-33E-PRF(Aeroautical Design Standard Performance Specification Handling Qualities Requirement) criteria, with consideration of category of the aircraft, missions, and environment. The numerical operations follow required or recommended procedures of flight test for compliance demonstration. Evaluation results are evaluated according to the rating specified in maneuverability ADS-33E-PRF. Results have identified to provide a satisfactory platform for flight dynamic model in the general helicopter simulator generated based on the RotorLibFDM, and can be used as a base for basic training and research.

• 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 Korean Society for Geospatial Information Science
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• v.11 no.4 s.27
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• pp.21-27
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• 2003

The rational polynomial coefficients(RPC) model is a generalized sensor model that is used as an alternative for the physical sensor model for IKONOS-2 and QuickBird. As the number of sensors increases along with greater complexity, and as the need for standard sensor model has become important, the applicability of the RPC model is also increasing. The RPC model can be substituted for all sensor models, such as the projective camera the linear pushbroom sensor and the SAR This paper is aimed at generating a RPC model from the physical sensor model of the KOMPSAT-1(Korean Multi-Purpose Satellite) and aerial photography. The KOMPSAT-1 collects $510{\sim}730nm$ panchromatic images with a ground sample distance (GSD) of 6.6m and a swath width of 17 km by pushbroom scanning. We generated the RPC from a physical sensor model of KOMPSAT-1 and aerial photography. The iterative least square solution based on Levenberg-Marquardt algorithm is used to estimate the RPC. In addition, data normalization and regularization are applied to improve the accuracy and minimize noise. And the accuracy of the test was evaluated based on the 2-D image coordinates. From this test, we were able to find that the RPC model is suitable for both KOMPSAT-1 and aerial photography.