• Korean Journal of Remote Sensing
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• v.23 no.6
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• pp.507-520
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• 2007

Satellite passive microwave(PM) sensors have been observing polar sea ice concentration(SIC), ice temperature, and snow depth since 1970s. Among them SIC is playing an important role in the various studies as it is considered the first factor for the monitoring of global climate and environment changes. Verification and correction of PM SIC is essential for this purpose. In this study, we calculated SIC from KOMPSAT-1 EOC images obtained from Arctic sea ice edges from July to August 2005 and compared with SSM/I SIC calculated from NASA Team(NT) algorithm. When we have no consideration of sea ice types, EOC and SSM/I NT SIC showed low correlation coefficient of 0.574. This is because there are differences in spatial resolution and observing time between two sensors, and the temporal and spatial variation of sea ice was high in summer Arctic ice edge. For the verification of SSM/I NT SIC according to sea ice types, we divided sea ice into land-fast ice, pack ice, and drift ice from EOC images, and compared them with SSM/I NT SIC corresponding to each ice type. The concentration of land-fast ice between EOC and SSM/I SIC were calculated very similarly to each other with the mean difference of 0.38%. This is because the temporal and spatial variation of land-fast ice is small, and the snow condition on the ice surface is relatively dry. In case of pack ice, there were lots of ice ridge and new ice that are known to be underestimated by NT algorithm. SSM/I NT SIC were lower than EOC SIC by 19.63% in average. In drift ice, SSM/I NT SIC showed 20.17% higher than EOC SIC in average. The sea ice with high concentration could be included inside the wide IFOV of SSM/I because the drift ice was located near the edge of pack ice. It is also suggested that SSM/I NT SIC overestimated the drift ice covered by wet snow.

• Korean Journal of Comparative Education
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• v.28 no.3
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• pp.135-159
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• 2018

This thesis compares and analyzes the dynamics between policy, knowledge and power of Myanmar's higher education development. The papers begins by exploring the dynamics during the Socialist Military Regime(1962~1988), the Collapse of Higher Education Era(1988~2010), Thein Sein's Reform Era(2010~2015) and the current Aung San Suu Kyi's Civilian Era(2015~Now). By highlighting recent dramatic policy changes, the article argues that the policy discourse on the subject of internationalization of higher education and the technocratization of education development policy by the current Civilian Government in its new policy discourse, that resulted in the active participation as well as the contributions of international donors has directly impacted on the policy dynamics around the Comprehensive Education Sector Review and the introduction of the National Education Strategic Plan 2016~2020. Further, by examining complex interaction between the current domestic education stakeholders and international donors in education sector in Myanmar, this thesis argues that the new analytical framework on the understanding of policy dynamics in developing countries goes beyond the national level. The paper argues that there needs to be broadening of the analytical framework towards the multidimensional analysis perspective that includes global, national as well as local level policy, knowledge and power dynamics in Myanmar's dynamically changing higher education sector.

• Food Science and Preservation
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• v.14 no.2
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• pp.148-153
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• 2007

The chemical components of flesh persimmon flowers (petal and calyx), and the qualify of hot-water extracts (teas) prepared from powders of these flower parts, were investigated In flesh petal and calyx, the contents of moisture, crude protein, crude lipid, and carbohydrate were 84.8% 0.4% 0.3% and 13.7% respectively. The values were not significantly different when the two tissues were compared. In petal and calyx respectively, the crude ash values were 0.5% and 1.1% of flesh weights, the vitamin C content were 192.3mg% and 392.7ng%, the flavonoid levels were 98.4 mg% and 355.2mg% and the carotenoid content were 0.8mg% and 3.8mg%. Hot air and freeze drying methods applied to petals, prior to powder preparation, did not affect the levels of soluble solids or soluble annins. Extract from calyx had higher L values, higher ${-\alpha}$ values, more soluble tannins, greater 1,1-diphenyl-2-picrylhy-drazylradical-scavenging activities, me lower pH values, than did exracts from petal. Fructose and glucose were higher in petal extract than in calyx extract, but sucrose was higher in calyx extracts. Extract of freeze-dried powdered petals had significantly higher free sugar levels than did exracts from petals dried with hot air. The major organic acids in extracts were citric acid, oxalic acid, and malic acid. The levels of organic acids were inversely related to free sugar levels in all flower parts and after all drying methods tested. Sensory tests of aroma, taste and overall acceptability yielded scores above medium for all teas, regardless of the flower part powdered, or the drying method used. The results show that the petal and calyx of persimmon may be used to make tea and perhaps other foods.

• Food Science and Preservation
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• v.19 no.4
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• pp.470-476
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• 2012

Enzymatic action and microbial growth degrade the quality of fresh-cut lettuce. Browning, a bad smell, and softening during storage are the major forms of quality deterioration. Health-oriented consumers tend to avoid foods treated with chemicals to maintain their freshness. This study was conducted to evaluate the change in the quality of fresh-cut lettuce with combined low-temperature blanching (LB) and ultrasonication (US). The optimum condition was selected using the response surface methodology (RSM), through a regression analysis with the following independent variables; the ultrasonication time (X1), blanching temperature (X2), blanching time (X3), and dependent variable; ${\Delta}E$ value (y). It was found that the condition with the lowest ${\Delta}E$ value occurred with combined 90s US and $45^{\circ}C$ 90s LB (US+LB). The combined treatment group (US+LB) was stored at $10^{\circ}C$ for 9 days with the control group and each single-treatment group, with low-temperature blanching and ultrasonication. Overall, the US+LB group had a significantly high $L^*$ value, which indicates significantly low $a^*$, $b^*$, ${\Delta}E$, browning index, PPO, and POD activity values, and a low total bacteria count (p < 0.05). The US+LB group also had the highest sensory score (except for aroma and texture; p > 0.05).

• Korean Journal of Plant Resources
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• v.31 no.4
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• pp.303-311
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• 2018

In this study, a preliminary evaluation of the antioxidant and anti-inflammatory activity of the Ficus erecta var. sieboldii (Miq.) King (FES) leaf extract has been performed to assess its potential as a natural resource for food and medicinal materials. FES was extracted using 70% EtOH and then fractionated sequentially using n-hexane, $CH_2Cl_2$, EtOAc, and n-BuOH. To screen for antioxidant and anti-inflammatory agents effectively, the inhibitory effect of the FES extracts on the production of oxidant stresses (DPPH, xanthine oxidase, and superoxide) and pro-inflammatory factors (NO, iNOS, COX-2, $PGE_2$, IL-6, and $IL-1{\beta}$) in the murine macrophage cell line RAW 264.7 activated with lipopolysaccharide (LPS) was examined. Among the sequential solvent fractions of FES, the $CH_2Cl_2$ and EtOAc fractions showed decreased production of oxidant stresses (DPPH, xanthine oxidase and superoxide), and the hexane and $CH_2Cl_2$ fractions of FES inhibited the production of pro-inflammatory factors (NO, iNOS, COX-2, and $PGE_2$). The $CH_2Cl_2$ fraction also inhibited the production of pro-inflammatory cytokines ($TNF-{\alpha}$, IL-6, and $IL-1{\beta}$). These results suggest that FES has a significant effects on the production of oxidant stresses and pro-inflammatory factors and may be used a natural resource for antioxidant and anti-inflammatory agents.

• Geophysics and Geophysical Exploration
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• v.8 no.1
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• pp.7-17
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• 2005

The determination of seismic velocities in refractors for near-surface seismic refraction investigations is an ill-posed problem. Small variations in the computed time parameters can result in quite large lateral variations in the derived velocities, which are often artefacts of the inversion algorithms. Such artefacts are usually not recognized or corrected with forward modelling. Therefore, if detailed refractor models are sought with model based inversion, then detailed starting models are required. The usual source of artefacts in seismic velocities is irregular refractors. Under most circumstances, the variable migration of the generalized reciprocal method (GRM) is able to accommodate irregular interfaces and generate detailed starting models of the refractor. However, where the very-near-surface environment of the Earth is also irregular, the efficacy of the GRM is reduced, and weathering corrections can be necessary. Standard methods for correcting for surface irregularities are usually not practical where the very-near-surface irregularities are of limited lateral extent. In such circumstances, the GRM smoothing statics method (SSM) is a simple and robust approach, which can facilitate more-accurate estimates of refractor velocities. The GRM SSM generates a smoothing 'statics' correction by subtracting an average of the time-depths computed with a range of XY values from the time-depths computed with a zero XY value (where the XY value is the separation between the receivers used to compute the time-depth). The time-depths to the deeper target refractors do not vary greatly with varying XY values, and therefore an average is much the same as the optimum value. However, the time-depths for the very-near-surface irregularities migrate laterally with increasing XY values and they are substantially reduced with the averaging process. As a result, the time-depth profile averaged over a range of XY values is effectively corrected for the near-surface irregularities. In addition, the time-depths computed with a Bero XY value are the sum of both the near-surface effects and the time-depths to the target refractor. Therefore, their subtraction generates an approximate 'statics' correction, which in turn, is subtracted from the traveltimes The GRM SSM is essentially a smoothing procedure, rather than a deterministic weathering correction approach, and it is most effective with near-surface irregularities of quite limited lateral extent. Model and case studies demonstrate that the GRM SSM substantially improves the reliability in determining detailed seismic velocities in irregular refractors.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.6
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• pp.1306-1313
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• 2011

A liquid fertilizer treated with slurry composting and biofiltration (SCB) process has been applied increasingly on agricultural field but the effects on the soil properties and crop production has not been throughly evaluated. This study was conducted to investigate the effect of the SCB application on soil chemical properties and the growth of radish and corn. SCB liquid fertilizer as a basal fertilization was treated with five levels based on $6kg\;10a^{-1}$ for radish and $10kg\;10a^{-1}$ for corn. The experimental design was the completely randomized block design with five levels and three replicates. Electrical conductivity (EC), $NO_3$-N, Exch. K and Exch. Na increased depending on the treatment levels of SCB. There were no changes in soil organic matter, Avail. $P_2O_5$, Exch. Ca and Exch. Mg. EC, $NO_3$-N and Exch. Na content decreased as precipitation increased. Especially, they decreased up to the initial condition before the treatment after the heavy rainy season in 2008. Although Exch. K decreased at the rainy season, they remained relatively higher content after the experiment on August, 2008. Fresh weight and the amount of N uptake of radish increased due to the levels of SCB, but corn did not present any significant increase. It is recommended that we need to decide the proper amount of SCB as well as the application method on the field to increase the productivity and decrease environmental stress. Additional experiments also need to clarify the effect of the trace element and heavy metal accumulations due to long term application of SCB.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.6
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• pp.1016-1022
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• 2011

Application of silicate fertilizers is typically practiced with several year's interval to amend soil quality and improve rice productivity at the paddy field in Korea. Most of silicate fertilizers applied in Korea is slag-originated silicate fertilizer. Some water soluble silicate fertilizers are manufactured and commercially available. The objective of this study was to assess changes of soil chemical properties in paddy field by applying slag-originated silicate fertilizer and water soluble silicate fertilizer. Field experiment was conducted on a silt loam paddy soil, where four levels of each silicate fertilizer were applied in soil at the rate of 0, 1, 2, 4 times of the recommended levels. Application of slag-originated silicate fertilizer increased soil pH, while no significant pH increase occurred with the treatment of water soluble silicate fertilizers. Soil pH increased 0.4~0.5 with the 1 time of recommended level of slag-originated silicate fertilizer. Available $SiO_2$ contents also significantly increased with the treatment of slag-originated silicate fertilizer at 15 and 35 days after treatment, while decreased after 60 days after treatment possibly due to rice uptake. Exchangeable Ca, Mg and available phosphate contents in soil increased with application of slag-originated silicate fertilizer, while a little increases for them were shown with the application of soluble silicate fertilizer. $SiO_2$/N ratios in rice straw for 1 time of recommended level of slag-originated silicate fertilizer was 11.5, while that of control was 8.4, which was much lower value. Throughout this study, soil application of slag-originated silicate fertilizer enhanced soil chemical properties, while water soluble silicate fertilizer application in soil needs further study resulting in a little effects on soil property.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.5
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• pp.734-744
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• 2011

A soil stabilization method is an effective and practical remediation alternative for arsenic (As) and heavy metal contaminated farmland soils nearby abandoned metal mine in Korea. This method is a technique whereby amendments are incorporated and mixed with a contaminated soil. Toxic metal bind to the amendments, which reduce their mobility in soil, so the successful stabilization of multi-element contaminated soil depends on the combination of critical elements in the soil and the type of amendments. The objective of this study is to investigate the treatment effects and applicability of limestone (LS) and steel refining slag (SRS) as the amendment for farmland soil contaminated with As and heavy metals, and a lab-column test was conducted for achieving this purpose. The result showed that soil treated with LS and SRS maintained pH buffer capacity and, as a result, the heavy metal leaching concentration was quite low below the water quality standard compared to untreated soil which leachate exceeding the water quality standard was observed, however, the arsenic concentration rather increased with increasing mixture ratio of SRS. This was believed to be related to phosphorus (P) contained in SRS, and dominancy in the competitive adsorption relation between As and P binding strongly to iron might be different according to soil characteristic. We suggested that LS is a effective amendment for reducing heavy metals in soil, and SRS should be used after investigating its applicability based on the adsorption selectivity of arsenic and phosphorus in selected soil.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.6
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• pp.1107-1111
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• 2011

Organic fertilizers application has become a popular alternatives to reduce the dependence on chemical fertilizer in Korean farming systems. In this study, we evaluated the nitrogen (N) use efficiency and growth performance of Chinese cabbage grown by black vinyl mulching after application of organic and chemical fertilizers compared with no-mulching. The treatments included chemical fertilizer alone as control (NPK, N-$P_2O_5-K_2O$ : $320-78-198kg\;ha^{-1}$), organic fertilizer alone (OF100), 70% organic fertilizer and 30% chemical fertilizer (OF70+N30), and 30% organic fertilizer and 70% chemical fertilizer (OF30+N70), which were all applied in the no-mulching plots and in plots with black vinyl mulching. Daily means soil temperature was $2^{\circ}C$ higher in the black vinyl mulched treatments throughout the 54 days compared with no-mulched treatments. OF100 with black vinyl mulching gave highest soil inorganic N content. Also, Chines cabbage yield increased 46% by black vinyl mulched compared with no-mulching in OF100 treatment. Without mulching, N use efficiency was, 44, 26, 29, and 27% in NPK, OF100, OF70+N30, and OF30+N70, respectively. However, black vinyl mulching much more effectively increased N use efficiencies by 56, 55, 51, and 39% in the same treatments in the order as mentioned above. Conclusively, combined organic and chemical fertilizers application with black vinyl mulching could be good practical technique to reduce a amount of used nitrogen because of its greater ability to enhance N use efficiency.