• Horticultural Science & Technology
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• v.28 no.3
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• pp.403-408
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• 2010

This study was carried out to investigate the physiological responses of $Rhododendron$ $mucronulatum$ Turcz. and $R.$ $indicum$ (L.) Sweet seedlings with 0%, 35%, 55% and 75% shading of full sunlight in polyethylene film house. The shading treatments were performed during the late growth season for each species (from Sept. 9 to Nov. 5, 2008). The shading treatment was effective in reducing the daily temperature by 0.9 to $1.7^{\circ}C$ during September and by 0.8 to $1.7^{\circ}C$ during October. Before the shading treatments, the water content of $R.$ $mucronulatum$ and $R.$ $indicum$ amounted to 68.5% and 66.3%, respectively. The water contents of two species after 75% shading treatment period decreased to 66.2% (3.4% reduction) and 65.9% (0.6% reduction), respectively. Notably, both species had a similar tendency indicating less reduction rate of water content with 75% shading. $R.$ $indicum$ showed higher photosynthetic capacity with higher level of shading, and its photosynthetic capacity reached the highest level ($9.63{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$). On the other hand, shading-treated $R.$ $indicum$ showed higher intercellular $CO_2$ concentration, stomatal conductance and transpiration rate (55% shading > 35% shading > 75% shading) than non-treated ones. In addition, non-treated seedlings showed higher water use efficiency than treated ones. In particular, it was found that the leaf color of $R.$ $mucronulatum$ turned equivalent to purple under full sunlight, while its leaf color kept equivalent more to green with higher level of shading, as evidenced even in naked eyes. According to comprehensive analysis using Munsell Color Chart on potential leaf color variations of $R.$ $mucronulatum$ depending on the level of shading, it was found that relatively many leaf colors under full sunlight were equivalent to R (red) and Y (yellow) chart, while relatively many leaf colors with higher level of shading were equivalent to G (green) and Y chart, where the latter still showed green color.

• Journal of Food Hygiene and Safety
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• v.32 no.6
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• pp.493-499
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• 2017

This study was conducted to monitor the current status of pesticide residues and sulfur dioxide in a total of 91 functional rice products from February to October 2016. Multi class pesticide multiresidue methods of 220 pesticides was performed by the GC/ECD, GC/NPD, GC/TOF/MS, LC/PDA, and LC/FLD. As a result of analysis, the pesticides were detected in 3 samples, representing a detection rate of 3.3%. The kind of pesticides was propiconazole and isoprothiolane used for germicide in agriculture or plant growth regulator purposes. The detected levels were 0.0340~0.0566 mg/kg, which were under the MRL (Maximum Residues Limits). The contents of sulfur dioxide in 91 samples by the Monier-Williams method were not detected. Risk assessment of pesticides evaluated using human health exposure with the ratio of EDI (Estimated daily intake) to ADI (Acceptable daily intake). %ADI (the ratios of EDI to ADI) were 0.24~1.25% with safety level.

• Horticultural Science & Technology
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• v.29 no.1
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• pp.29-35
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• 2011

Individual ion concentrations and ionic contributions to EC reading in the circulated nutrient solution are the important factors to be considered for stable EC-based closed-loop soilless culture. This study was conducted to determine appropriate ion-analysis intervals of the circulated nutrient solutions based on ion concentration, ion balance, and ion electrical conductivity under different renewal intervals in EC-based nutrient control systems for sweet peppers (Capsicum annum L. 'Fiesta') in early growth stage. Average node numbers of the plants were 13 and 18 when the experiment started and finished, respectively, and three plants were grown in each rockwool slab. Four different renewal intervals of circulated nutrient solutions such as 1, 2, 3, and 4 weeks were used as treatment. Nutrient solutions were supplied to the plants based on integrated radiation. Drainage was collected into drain tanks after irrigation ended in the day and then mixed with fresh water until the EC reaches 2.69 $dS{\cdot}m^{-1}$. The replenished nutrient solution was supplied to the plants in the next day. Ion concentrations of the individual ions periodically analyzed in the circulated nutrient solutions showed no significant differences among the treatments during the experimental period. Ion concentrations of $K^+$, $Ca^{2+}$, $Mg^{2+}$, $Na^+$, $NO_3{^-}$, ${SO_4}^{2-}$, ${PO_4}^{3-}$, and $Cl^-$ varied within 5-8, 11-14, 2.0-2.7, 0.5-0.6, 14-19, 4-5, 1-4, and 0.3-0.5 $meq{\cdot}L^{-1}$, respectively. Ion balance showed a consistent tendency over all the treatments and especially $K^+$ : $Ca^{2+}$ and ${SO_4}^{2-}$ : ${PO_4}^{3-}$ played great roles in the cation and anion balances in the nutrient solutions, respectively. Activity coefficients of ions such as $K^+$, $NO_3{^-}$, and $H_2PO_4{^-}$ varied within 0.8-0.9 and those of $Ca^{2+}$, $Mg^{2+}$, ${SO_4}^{2-}$ varied within 0.5-0.6, showing little changes with time. Ionic contributions of $K^+$ and $NO_3{^-}$ to EC reading were the greatest followed by $Ca^{2+}$, ${SO_4}^{2-}$, and $Mg^{2+}$ in the order. From the results, we thought that allowable ranges in ion concentration, ion balance, and subsequent individual ionic contributions to EC reading would be obtained within 4-week renewal interval of nutrient solution in EC-based closed-loop soilless culture for sweet pepper plants.

• Journal of Korean Neurosurgical Society
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• v.30 no.sup2
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• pp.189-196
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• 2001

Objective : We tested the hypothesis that photodynamic therapy(PDT) with Photofrin inhibits tumor invasion of U87 human glioma cells using several in vitro assay to measure tumor invasiveness. The effects of PDT on cell growth, directional migration and cell invasion were investigated. Material and Method : Tumor cells were treated with Photofrin at various doses and at a fixed optical(632nm) dose of $100mJ/cm^2$. Cytotoxicity was tested using the MTT method. Invasion assays including the matrigelartificial basement membrane barrier migration and spheroid confrontation with confocal microscopic analysis were used to study the relationship between PDT and invasiveness. Result : U87 cells showed a dose dependent cytotoxic response to increasing Photofrin dose. Data from the matrigel artificial basement membrane assay indicate that PDT inhibits the U87 cell migration dose dependently. Low doses of subcytotoxic PDT treatment, such as 2.5ug/ml Photofrin dose, also appeared to significantly inhibit migration of U87 cells(p<0.05). In co-cultures between U87 cell spheroids and brain aggregates, progressive invasion with destruction of the brain aggregate occurs. The extent of tumor cell infiltration and proportion or intact brain aggregate remaining after 24h differs in Photofrin PDT treated versus Photofrin only control, with changes suggestive of a dose-response effect. Conclusion : our data indicate that PDT with Photofrin significantly inhibits the invasiveness of U87 cells, and this inhibition is dose dependent.

• Journal of Korean Society of Forest Science
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• v.90 no.1
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• pp.64-73
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• 2001

Generally potassium in the soil can be remained as water soluble, exchangeable, and available types, respectively. Theses types of potassiums are also known to keep their kinetic relationships to each other. The Purpose on this research was to investigate types and relationships of potassium in the soil, and the characteristics of potassium supply in different forest soils. The results could be summarized as follows; 1. The amounts of available potassium in A and B horizon soils by continuous leaching with 0.01N-HCl were as follows : for A Horizon soils, pohang(Gray brown forest soils), Changsung (Brown forest soils), and Youngwol(Dark red forest soils) were ranged from 0.2me/l00g to 0.8me/100g, Taean(Red and Yellow forest soils) was 0.1-0.6me/100g, Kapyung(Brown forest soils) was 0.2-0.4me/100g. For the B layer, Youngwol was 0.1-0.5me/100g, Pohang, Taean, Kapyung were 0.1-0.4me/100g, Changsung was 0.1-0.3me/100g, respectivly. 2. Of ten times-pulse leaching with 0.01N-HCl for A layer soil, more 80% of total available potassium leaching were recovered by the second pulse as leachate for Pohang, Changsung, Youngwol, while similar amounts of potassium in the leachate were obtained with the third pulse leaching for Kapyung, Taean, respectively, On the other hand, the 80 % release of available potassium from the B layer soil was obtained by the second pulse leaching for all areas investigated. 3. For the relationships between soluble potassium and exchangeable potassium, the exchangeable potassium was increased while the soluble potassium was not changed significantly in B layer. And both soluble potassium and exchangeable potassium in A layer were similar. For the relationship between exchangeable potassium and available potassium in both A and B layers, the amounts of available potassium increased by 1.2 to 1.5 times as the exchangeable potassium increased. 4. For distribution of all types of potassium throughout locations investigated, the types of potassium were in the decreasing orders of available, exchangeable, and soluble. 5. The simplified method for an analysis of all types of potassium by sequential leaching with 0.01N-HCl should be developed not only with respect to time-saving and efficiency but also verification of the relationship between available potassium and tree growth.

• Korean Journal of Remote Sensing
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• v.14 no.1
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• pp.83-94
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• 1998

To have a basic idea on the spectral reflectance signature in paddy rice canopy, we measured spectral reflectance from paddy rice canopy(Ilpumbyeo) using spectroradiometer (GER Inc. SFOV : 0.35~2.50 ${\mu}{\textrm}{m}$) in situ weekly or biweekly from transplanting to ripening stage. Spectral reflectance of the visible range (0.4~0.7 ${\mu}{\textrm}{m}$) was decreased to below 5% and then slightly increased again after heading stage in rice canopy. Meanwhile spectral reflectance of the near-infrared range (0.7~1.1 ${\mu}{\textrm}{m}$) was increased to 40~50% and then decreased a great deal after panicle initiation stage in rice canopy. Landsat TM equivalent band set ($\bar{p}$$_{TMi}$) was created by averaging spectral reflectance values to the real TM bands. Correlation analysis between the rice crop variables (LAI, total dry matter) and TM equivalent band set ($\bar{p}$$_{TMi}$) showed that LAI and total dry matter of rice were highly correlated with visible bands such as $\bar{p}$$_{TM1}$, $\bar{p}$$_{TM2}$, and $\bar{p}$$_{TM3}$. Ratio values ($\bar{p}$$_{TMi}$/$\bar{p}$$_{TMi}$) such as $\bar{p}$$_{TM4}$/$\bar{p}$$_{TM2}$ were also highly correlated with rice crop variables such as LAI and total dry matter.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.14 no.5
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• pp.25-42
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• 2019

The purpose of this study is to analyze the effect of internal competence of small business on the competitive advantage and start-up intention. Through this, which key competence of small business can be proposed for market growth against of large companies that have a great capital power. Also, implications for development direction can be suggested. For this purpose, technology capability, financing capability, marketing capability, and product/service differentiation capability factors were set as independent variables, as well as competitive advantage as a mediating factor, and startup intention to be franchiser as a dependent variable. For the analysis, a structured questionnaires survey was conducted to 276 domestic small business in capital area. The main results are as follows. First, in relation to the internal competency and the competitive advantage of small businesses, it was found that technological capabilities, financing capabilities and product (service) differentiation have a positive effect on competitive advantage. Second, the relationship between the internal capacity of a small entity and startup intention to commercialize a franchiser business indicates that its financing capacity and marketing capabilities have a positive effect on startup intention to commercialize the business, and that competitive advantage has a significant effect on startup intention to commercialize the franchise. Third, competitive advantage was found to mediate the relationship between internal competency and startup intention. Finally, it was shown that the internal capacity of a small business has a regulating effect in relation to its financing capacity, marketing capabilities and startup intention to commercialize the franchise, and that it also had a regulating effect in relation to its relationship with its competitive advantage and franchise suitability. Based on the above results, if small business can take competitive advantage in the market, they also consider startup intention to commercialize a franchiser, in addition, it is expected that one suggestion can be made from an internal capacity perspective required more emphasis on operations and management as an alternative to expanding small businesses' business, including market access measures that can be linked to internal capacity factors of small businesses.

• Journal of the Korea Society of Computer and Information
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• v.6 no.4
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• pp.188-205
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• 2001

Insurer's duty of declaration is based on reciprocity of principle of the highest good, and recently it is widely recognized in the British and American insurance circles. The conception of fiduciary relationship is no longer equity or the legal theory which is only confined to the nations with Anglo-American laws. Therefore, recognizing the fiduciary relationship as the essence of insurance contract, which is more closely related to public interest than any other fields. will serve an efficient measure to seek fair and reasonable relationship with contractor, and provide legal foundation which permits contractor to bring an action for damage against violation of insurer's duty of declaration. In the future, only when the fiduciary relationship is approved as the essence of insurance contract, the business performance and quality of insurance industry is expected to increase. Therefore, to keep well this fiduciary relationship, or increase the fiduciary relationship persistency rates seems to be the bottom line in the insurance industry. In this paper, we developed a fiduciary relationship maintenance ratio based on comparison by case, which is represented with usually maintained contract months to paid months, based on each contract of the basis point. In this paper we have developed a new business model seeking the maximum profit with low cost and high efficiency, management policy of putting its priority on its substantiality, as an improvement measure to break away from the vicious circle of high cost and low efficiency, and management policy of putting its priority on its external growth(expansion of market share).

• 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 Soil Science and Fertilizer
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• v.40 no.1
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• pp.85-94
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• 2007

To determine the influence of food waste compost (FWC) application on paddy soil, FWC was applied to the paddy soil and then compared with farmer's practice as to the effects on rice and soil environment. Initially, pig manure compost (PMC) had high content of phosphorus ($15g\;kg^{-1}$) and potassium ($23g\;kg^{-1}$), while FWC had high content of total nitrogen ($13g\;kg^{-1}$) and salinity ($18.5g\;kg^{-1}$). Comparison was also made between chemical fertilizer and FWC use as a trial in the paddy field under the clay loam and sandy loam soil. In the panicle formation stage, chemical fertilizer application was proper in clay loam while PMC application was proper in sandy loam. However, chemical fertilizer produced higher yield compared to compost treatment, both on clay loam and sandy loam with 20~25% and 17~19%, respectively. The lower yield in sandy loam maybe due to slow mineralization of compost such that the crop did not effectively use it. Organic matter content in paddy soil after experiment was higher in FWC and PMC plots compared to that in chemical fertilizer plots. But the other soil properties were comparable. Therefore, the FWC compost had little effect on soil when it use as a trial in paddy field. Likewise, after the application of FWC as a trial, analysis of nitrate nitrogen and ammonium nitrogen in the surface water and 60 cm depth of paddy soil water nine days after planting was done. Results revealed that concentration of ammonium nitrogen was similar to irrigation water while nitrate nitrogen concentration was not detected, and hence did not contribute to water pollution. It is concluded that the application of FWC in the paddy field had not affected on environmental pollution in the paddy field. But its use as compost during rice culture reduced yield quantity. Such study should include selection of compost material, amount and method of compost application.