• Clinical and Experimental Pediatrics
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• v.48 no.1
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• pp.55-62
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• 2005

Purpose : We compared the therapeutic efficacy of lamivudine and alpha-interferon in children with chronic hepatitis B two years after the initiation of treatment, so that we could verify the safety and long term efficacy of lamivudine in children. Methods : We prospectively studied 44 children(32 male and 12 female; age, 1-18 years, mean, 9 years) treated for chronic hepatitis B from September 1996 to June 2004 in Kyungpook National University Hospital in Korea. Twenty three children were treated with interferon, and 21 with lamivudine. Treatment efficacy was defined as the normalization of ALT and hepatitis B virus(HBV) DNA levels, loss of HBsAg and HBeAg seroconversion at two years after the initiation of treatment. Results : Among the 23 children treated with interferon, the ALT level normalized in 10 children(43 %) and HBV DNA was undetectable in 12 children(52%). HBsAg was undetectable in one child (4 %) and HBeAg seroconversion occurred in nine children(39%) two years after the initiation of treatment. In comparison, among the 21 children treated with lamivudine, ALT normalized in 20 children (95%), HBV DNA in 19(90%), HBsAg in 5(24%), and HBeAg seroconversion occurred in 13(62%). Above all, in the lamivudine treated group under the age of seven, HBeAg and HBsAg seroconversion occurred in six(75%) and five(63%) out of the eight children respectively, which showed superior HBsAg seroconversion rate if treated in preschool aged children. Conclusion : We believe that the therapeutic efficacy of lamivudine in children with chronic hepatitis B could be better than interferon with fewer side effects, especially in preschool aged children.

• Korean Journal of Remote Sensing
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• v.34 no.2_1
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• pp.267-282
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• 2018

Despite the continuous development of phenology detection studies using satellite imagery, verification through comparison with the field observed data is insufficient. Especially, in the case of Korean forests patching in various forms, it is difficult to estimate the start of season (SOS) by using only satellite images due to resolution difference. To improve the accuracy of vegetation phenology estimation, this study reconstructed the large scaled forest type map (1:5,000) with MODIS pixel resolution and produced time series vegetation phenology curves from Normalized Difference Vegetation Index (NDVI) and Enhanced Vegetation Index (EVI) derived from MODIS images. Based on the field observed data, extraction methods for the vegetation indices and SOS for Korean forests were compared and evaluated. We also analyzed the correlation between the composition ratio of forest types in each pixel and phenology extraction from the vegetation indices. When we compared NDVI and EVI with the field observed SOS data from the Korea National Arboretum, EVI was more accurate for Korean forests, and the first derivative was most suitable for extracting SOS in the phenology curve from the vegetation index. When the eight pixels neighboring the pixels of 7 broadleaved trees with field SOS data (center pixel) were compared to field SOS, the forest types of the best pixels with the highest correlation with the field data were deciduous forest by 67.9%, coniferous forest by 14.3%, and mixed forest by 7.7%, and the mean coefficient of determination ($R^2$) was 0.64. The average national SOS extracted from MODIS EVI were DOY 112.9 in 2014 at the earliest and DOY 129.1 in 2010 at the latest, which is about 0.16 days faster since 2003. In future research, it is necessary to expand the analysis of deciduous and mixed forests' SOS into the extraction of coniferous forest's SOS in order to understand the various climate and geomorphic factors. As such, comprehensive study should be carried out considering the diversity of forest ecosystems in Korea.

• Archives of design research
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• v.15 no.4
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• pp.97-110
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• 2002

As users environments change, users primary needs for homepages also change more complicatedly. Today, users do not only want usability for homepages, but also to feel appropriate emotional experiences. Despite users needs, users do not always experience appropriate emotions that are conveyed by designers through homepage. I In this research paper, we analyzed the related factors with the emotional quality, which means the degree that users feel target emotions intended by designers. For analyzing factors related with the emotional quality, three hypotheses were verified; the factor of an emotion, the factor of users and the factor of designers. As the factor of emotions, the first hypothesis is that unclear emotional dimensions in users minds are related with the emotional quality. The second hypothesis, as the factor of users, is that the diversity of users experiences by same homepage is related with the emotional quality. The third hypothesis, as the factor of designers, is that the appropriate selection of design elements is related with the emotional quality. In the previous research, we selected the basic 13 emotional dimensions and 30 representative emotional words based on the statistical results and evaluations by professional designers. For this research, we conducted an experiment and user survey. In the experiment, we asked 30 designers to design homepages focusing on the typical emotion that was presented by a researcher. Based on the designing process and user evaluation, we performed statistical analyses: ANOVA with Tukey post hoc method and Factor Analysis. We found the discrepancy between the emotions that designers intend and the actual emotions that users experienced from homepages. From the result of analysis, we know that the factor of users and the factor of designers related with the emotional qualities, but the factor of emotions did not. The definiteness of emotions did not relate with the emotional quality. However, the diversity of emotions that users feel seeing the same homepages and design elements that designers chose for conveying target emotion related with the emotional quality.

• Journal of Applied Biological Chemistry
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• v.57 no.1
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• pp.73-81
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• 2014

The present study was carried out to assess exposure and risk to thiophanate-methyl wettable powder for agricultural worker during mixing/loading and application with power sprayer in green pepper, cucumber and apple fields. Dermal exposure was measured with patches, gloves, socks and masks, while inhalation exposure was evaluated with personal air pump and solid sorbent. Those methods were full validated before experiment. During mixing/loading, dermal exposure amount in green pepper, cucumber and apple fields was $24.0{\pm}6.7$, $4.5{\pm}1.5$ and $18.5{\pm}0.6mg$, corresponding to mean 0.007, 0.001 and 0.005% of prepared active ingredient, respectively. The major exposed part for mixer/loader was hands (78-92%). Dermal exposure amount for applicator in green pepper, cucumber and apple fields was $84.9{\pm}14.0$, $34.0{\pm}20.8$ and $30.7{\pm}9.1mg$, corresponding to mean 0.024, 0.016 and 0.013% of applied active ingredient, respectively. The main body parts of exposure in apple field were hands, while thighs and shins in other fields. Inhalation exposure amount in green pepper, cucumber and apple fields was $1.5{\pm}2.2$, $52.7{\pm}48.9$ and $4.0{\pm}4.9{\mu}g$ during mixing/loading and $0.2{\pm}0.1$, $23.2{\pm}12.4$ and $0.4{\pm}0.6{\mu}g$ for applicator, respectively. These results were suggested that main factors affecting dermal exposure were contact frequency to the plants, foliage density, hygienic behavior, work type, and working environment, while inhalation exposure was affected mainly by working environment, especially wind. In risk assessment, margin of safety for thiophanate-methyl in all cases was over 1. However, during application in green pepper field, margin of safety was close to 1.

• Korean Journal of Remote Sensing
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• v.33 no.2
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• pp.243-248
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• 2017

Sea ice which is an important component of the global climate system is being actively detected by satellite because it have been distributed to polar and high-latitude region. and the sea ice detection method using satellite uses reflectance and temperature data. the sea ice detection method of Moderate-Resolution Imaging Spectroradiometer (MODIS), which is a technique utilizing Ice Surface Temperature (IST) have been utilized by many studies. In this study, we propose a simple and effective method of sea ice detection using the dynamic threshold technique with no IST calculation process. In order to specify the dynamic threshold, pixels with freezing point of MODIS IST of 273.0 K or less were extracted. For the extracted pixels, we analyzed the relationship between MODIS IST, MODIS $11{\mu}m$ channel brightness temperature($T_{11{\mu}m}$) and Brightness Temperature Difference ($BTD:T_{11{\mu}m}-T_{12{\mu}m}$). As a result of the analysis, the relationship between the three values showed a linear characteristic and the threshold value was designated by using this. In the case ofsea ice detection, if $T_{11{\mu}m}$ is below the specified threshold value, it is detected as sea ice on clear sky. And in order to estimate the performance of the proposed sea ice detection method, the accuracy was analyzed using MODIS Sea ice extent and then validation accuracy was higher than 99% in Producer Accuracy (PA).

• Spatial Information Research
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• v.22 no.1
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• pp.55-63
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• 2014

Near surface air temperature data which are one of the essential factors in hydrology, meteorology and climatology, have drawn a substantial amount of attention from various academic domains and societies. Meteorological observations, however, have high spatio-temporal constraints with the limits in the number and distribution over the earth surface. To overcome such limits, many studies have sought to estimate the near surface air temperature from satellite image data at a regional or continental scale with simple regression methods. Alternatively, we applied various Kriging methods such as ordinary Kriging, universal Kriging, Cokriging, Regression Kriging in search of an optimal estimation method based on near surface air temperature data observed from automatic weather stations (AWS) in South Korea throughout 2010 (365 days) and MODIS land surface temperature (LST) data (MOD11A1, 365 images). Due to high spatial heterogeneity, auxiliary data have been also analyzed such as land cover, DEM (digital elevation model) to consider factors that can affect near surface air temperature. Prior to the main estimation, we calculated root mean square error (RMSE) of temperature differences from the 365-days LST and AWS data by season and landcover. The results show that the coefficient of variation (CV) of RMSE by season is 0.86, but the equivalent value of CV by landcover is 0.00746. Seasonal differences between LST and AWS data were greater than that those by landcover. Seasonal RMSE was the lowest in winter (3.72). The results from a linear regression analysis for examining the relationship among AWS, LST, and auxiliary data show that the coefficient of determination was the highest in winter (0.818) but the lowest in summer (0.078), thereby indicating a significant level of seasonal variation. Based on these results, we utilized a variety of Kriging techniques to estimate the surface temperature. The results of cross-validation in each Kriging model show that the measure of model accuracy was 1.71, 1.71, 1.848, and 1.630 for universal Kriging, ordinary Kriging, cokriging, and regression Kriging, respectively. The estimates from regression Kriging thus proved to be the most accurate among the Kriging methods compared.

• Journal of Distribution Science
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• v.9 no.1
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• pp.39-48
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• 2011

One of the major reasons for fierce competition among firms is that they strive to increase their own market shares in the same market with similar and apparently undifferentiated products in terms of quality and perceived benefit. Due to such changes in the marketing environment, differentiated after-sales service and diversified promotion strategies have become more important in the race to gain a competitive advantage. Price discount is one of the popular promotion strategies that most retailers use, especially to increase sales, but offering a price discount does not always lead to the expected result. If marketers apply an identical price-promotion strategy without considering the characteristic differences in products and consumer preferences, the discounted price itself may make people skeptical about the quality of the product. Moreover, the changes in perceived value may appear differently depending on factors such as consumer involvement. This implies that variables such as the level of consumer involvement, brand loyalty, and external reference prices, in reality, would have different effects on how consumers perceive the value of price discounts. The variables that affect consumers' perceived values and buying decisions are diverse and complicated. Several studies have examined the effects of such variables as external reference price, selling price, and brand on consumers' perceived value of products. Results have not shown consistent patterns. Therefore, we must note that the factors affecting consumers' value perceptions and buying behaviors are diverse and that the results of studies on the same dependent variable come out differently depending on what that variable is. This study focused on the level of consumer involvement as a salient variable that supposedly affects the perceived value of a product, willingness to buy, and search intentions. We tried to examine whether a price discount affects the perceived value-such as perceived acquisition value and perceived transaction value-in different ways depending on the level of consumer involvement. In addition, we proposed managerial implications that marketers need to consider as a whole, for instance, product attributes, brand loyalty, and involvement and then established a differentiated pricing strategy, case by case, in order to effectively enhance consumers' perceived values. As a result, we found that perceived transaction value positively affects perceived acquisition value and when discounting the price of a high-involvement product enhances the consumer's willingness to buy, but perceived acquisition value does not affect the search intentions significantly. In the case of discounting prices of low-involvement products, on the other hand, the perceived transaction value has a positive effect on the willingness to buy, but the negative effect of perceived acquisition value on the search intentions was not significant. We suppose that people doubt a product's quality because of a declined perceived quality derived from a price discount. Even though the price discount enhanced the transaction value, people eventually increased their level of searching for additional product information. From the results of this study, we suggest that marketers ought to establish an appropriate value-enhancing strategy based on the understanding of which perceived value consumers rely on more when they conduct purchasing behavior because consumers perceive the degree of importance of acquisition value or transaction value differently, depending on their level of involvement.

• Korean Journal of Psychosomatic Medicine
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• v.15 no.2
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• pp.81-87
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• 2007

Objectives : The distressed personality (type-D) pattern, consisting of negative affectivity and social inhibition, has been shown by Denollet et al. For measuring the Type D characteristics, Denollet has devised the 14 item Type D scale (DS14). In the present study, this instrument was translated into Korean. The reliability and validity of the Korean DS14 was pilot tested. Methods : Preliminary version of the total 17-item DS14 scale was translated into Korean. 372 controls that did not have any coronary heart diseases (CHD) were randomly sampled in Seoul and Gyeonggi province. Preliminary Korean version was applied to controls and 14 items were finally selected to maximize reliability of the scale. We compared the distribution of type-D personality among the normal controls, hypertensive patients, and the CHD patients. Results : 7 of 10 items in social inhibition were selected and final 14-item version was made. The internal consistency of negative affectivity (0.817) and social inhibition (0.797) were high. In addition, the prevalence of type-D personality in the CHD patients group was significantly higher than normal controls. Conclusion : These findings suggest that Korean version of DS14 is a valid tool for measuring the type D characteristics. Type-D characteristics can be suggested to predict adverse prognosis in patients with CHD.

• Korean Journal of Clinical Laboratory Science
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• v.49 no.4
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• pp.350-358
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• 2017

The hemolysis index (HI) is semi-quantitative marker for hemolysis. Because the characteristics of the HI vary from one commercial platform to another, no standardization or harmonization of the HI is currently available. Specimens (N=40) randomly selected from clinical patients were artificially hemolyzed in vitro. The serum of the specimens was then diluted with a 20 mg/dL difference between 0~300 mg/dL based on serum hemoglobin measured using the XE-2100 hematology automation equipment (Sysmex, Japan). Diluted serum was measured using the Hitachi-7600 biochemical automation equipment (Hitachi, Japan) to differentiate between HI and serum hemoglobin. The data showed linearity between HI and serum hemoglobin and that HI 1 contained approximately 20 mg/dL of serum hemoglobin. To determine the blood rejection threshold, the HI was divided into three groups: HI 0~1, HI 4~6, HI 9~15. After another batch of clinical specimens (N=40) was measured using a Hitachi-7600 (Hitachi, Japan), each specimen was moved forward and backward with the piston of the syringe to induce an artificial in vitro hemolysis, then measured again with a Hitachi-7600 (Hitachi, Japan). The percentage difference between the three groups was analyzed by ANOVA or the Kruskal-Wallis test. In the post-test, there were significant differences between the HI 0~1 and the HI 5~6: Glucose, creatinine, total protein, AST, direct bilirubin, uric acid, phosphorus, triglyceride, LDH, CPK, Magnesium, and potassium levels. Because many clinical tests differed significantly, the threshold for hemolysis could be appropriate for HI 5 (serum hemoglobin 100 mg/dL).

• Korean Journal of Food Science and Technology
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• v.27 no.2
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• pp.156-163
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• 1995

The practical shelf-life of pasteurized Korean rice wine ‘Yakju’, aseptically packed in Tetra-pak, was determined. The test sample products were stored at $4^{\circ}C,\;20^{\circ}C,\;30^{\circ}C\;and\;35^{\circ}C$ for 19 weeks, and the quality assessment was made at two weeks interval. The quality parameters evaluated were pH, acidity, reducing sugar, absorbance at 370 nm, total and acid producing bacteria, yeast and mold, and sensory quality. No meaningful changes of pH and reducing sugar were noticed during the storage for 19 weeks at temperatures tested. The absorbance at 370 nm increased slightly during storage. The total numbers of microorganisms in the product decreased during storage and a drastical reduction of acid producing bacteria was observed after 6 weeks of storage. Both yeast and mold were not found in the pasteurized products. The sensory quality of stored rice-wine was evaluated by triangle test and scoring test. The panels could distinguish the product stored at $4^{\circ}C$ from other products stored at the higher temperatures for over 6 weeks. The overall acceptance of the product decreased gradually during storage, and the rate constants for the changes were $7.93{\times}10^{-3},\;at\;20^{\circ}C,\;9.69{\times}10^{-3}\;at\;30^{\circ}C\;and\;13.4{\times}10^{-3}\;at\;35^{\circ}C$, respectively. The activation energy estimated by Arrhenius equation was 24,795 kJ/kmol. The estimated shelf-life of Yakju pasteurized and aseptically packed was 24 months at $10^{\circ}C$, 16 months at $25^{\circ}C$ and 14 months at $25^{\circ}C$. The shelf-life of Yakju in Seoul was calculated to be 20 months, based on the monthly average temperature of the city.