• Journal of Korea Port Economic Association
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• v.27 no.1
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• pp.185-212
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• 2011

The purpose of this paper is to show the empirical analysis way for measuring the seaport efficiency by using the previous radial model and the newly modified non-radial models( panel additive model, panel RAM model, and panel SBM model)with Spearman rank order correlation coefficient(SROCC) for 20 Korean ports during 11 years(1997-2007) for 1 inputs(port investment amount) and 4 outputs(Number of Ship Calls, Port Revenue, Customer Satisfaction Score for Port Service and Container Cargo Throughput). The main empirical results of this paper are as follows. First, consistency ratio of SROCC in terms of efficiency scores between radial and panel Additive model was over about 76% and overall consistency ratio was about 71.6%. Second, an efficiency of panel RAM model was higher than that of radial model with similarity. However, panel SBM model shows the very similar efficiency scores with panel radial model. Third, the slack size of radial model is smaller compared to non-radial model. Models' ranking orders in terms of efficiency scores, number of efficient ports are panel RAM model, panel SBM model, and radial model. The order from the minimum efficiency scores was the same order like just before. The policy implication to the Korean seaports and planner is that Korean seaports should introduce the new methods like non-radial models(panel additive model, panel RAM model, and panel SBM model) for measuring the port performance.

• Korean Journal of Soil Science and Fertilizer
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• v.1 no.1
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• pp.117-123
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• 1968

A simplest and best method to find out lime requirement for Korean soils is described. Twenty six top soil samples were collected from various localities and chemical characteristics were dertermined. Three different buffer curve methods were employed as the standard to find out the most reliable test for lime requirement. In addition, the lime requirement test by the Shoemaker's and Woodruff's as well as the O.R.D. kit method were compared with the most reliable buffer curve method. The results may be summarized as follows. 1. The regression equation of the most reliable lime requirement by buffer curve method, y, on percent base saturation of various soils, X, was y=9.69-0.106 X and the negative correlation coefficient r=-0.84 was statistically significant at 5% level. 2. Lime requirement test by the best, buffer curve, method was more well correlated with the sum of exchangeable hydrogen and exchangeable aluminum contents of the soil samples than the exchangeable hydrogen content only. 3. The ordinary buffer curve method for lime requirement is more reasonable than the lime requirement test by the buffer curve prepared after addition of 1 normal potassium chloride or calcium chloride solutions. 4. The lime requirement tests by the most reasonable buffer curve method, X, and by the Woodruff's, the Shoemaker's and O.R.D. kit were compared. The best method for laboratory lime requirement test was the Shoemaker's method and the O.R.D. kit method also was good enough for the field test and these two method are recommended as the unified method of lime requirement test in each soil testing laboratories throughout Korea.

• Journal of Food Hygiene and Safety
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• v.20 no.3
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• pp.141-146
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• 2005

A simple and sensitive analysis method based on reverse phase (RP) HPLC with UV detector was developed for simultaneous determination of chlorophyll a and b, pheophorbide a and $\beta-Carotene$ in Chlorella and Spirulina products. For added concentration $(50\;\mug/ml)$ of chlorophyll a and b, pheophorbide a and $\beta-Carotene$, recoveries of those were 70.3, 71.6, 60.1 and $90.5\%$, respectively, with relative standard deviations of 2.8,6.0, 10.6 and $10.4\%$. Limit of detection and quantification had ranges of $0.1\sim1.0\;\mug/ml$ and $0.2\sim2.0\;\mug/ml$, respectively. Calibration curve was linear with correlation coefficient of 0.995 for chlorophyll a and b, pheophorbide a and $\beta-Carotene$. Results of simultaneous determination in Chlorella and Spirulina products were showed ranges of $121.g\sim543.0\;\mug/ml$ for chlorophyll a,$0.6\sim160.0\;\mug/ml$ for chlorophyll b, $19.2\sim60.3\;\mug/ml$ for pheophorbide a and $383.6\sim1713.7\;\mug/ml$ for $\beta-Carotene$, respectively. Chlorophyll b contents in Chlorella products were detected above 30 times level to those in Spirulina products. $\beta-Carotene$ contents in Spirulina products were detected 2.7 times level to those in Chlorella products.

• Journal of Food Hygiene and Safety
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• v.35 no.3
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• pp.225-233
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• 2020

By the standards and specifications for hygiene products, three test methods for formaldehyde are specified for each item type of hygiene product. After derivatization using acetylacetone and 2,4-dinitrophenylhydrazine (2,4-DNPH), formaldehyde is analyzed by spectrophotometer and high-performance liquid chromatography (HPLC). Validation of the three test methods was performed on tissue, diaper lining and waterproof layer, and panty liner products. The results of linearity (R²), limit of detection (LOD), limit of quantification (LOQ), recovery rate (%) and reproducibility (%), showed that all three methods are suitable for analyzing formaldehyde in hygiene products. After derivatization with 2,4-DNPH and cetylacetone, formaldehyde was analyzed at 0, 3, 6, 9, 24 and 48 hours by HPLC. Formaldehyde derivatized with 2,4-DNPH showed no statistically significant change in formaldehyde peak area over time (P>0.05). But, acetylacetone-derivatizated formaldehyde showed a negative correlation coefficient (r) over time (P<0.01). We investigated the residual amounts of formaldehyde in 205 hygiene products distributed in Busan. Among 74 disposable diaper products tested, 73 had low concentrations of formaldehyde (0.13-29.87 mg/kg). Moreover, formaldehyde was not detected in any of 78 tissue, 27 disposable paper towel, 12 disposable dishcloth, 7 paper cup, one brand of paper straw and 6 disposable napkin products.

• Korean Journal of Soil Science and Fertilizer
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• v.9 no.1
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• pp.47-55
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• 1976

This study is conducted to find out potential evapotranspiration values computed by a reasonable formula which is well suited among the existing ones for Suweon area. Each formula based on the data from Suweon Agricultural Meteorological Station during 1964 to 1973. Five formulas which are Blanney-Criddle, Thornthwaite, Penman, Jensen-Haise and Truc have been applied for calculation of potential evapotanspiration. Results obtained are summarized as follows. 1. Potential evapotranspiration of Suweon area shows uni-modal distribution which maximum value occurs in summer and minimum value occurs in winter. Annual potential evapotranspiration computed by Blanney-Criddle formula is 1,377 mm and that computed by others ranges from 714mm to 896mm. 2. Potential evapotranspiration computed by Blanney-Criddle formula is higher value than that computed by others, and among the other formulas it's values show little differences. However, relationships between the former and the mean of four others is highly correlated. 3. In comparison with potential evapotranspiration computed by formulas and actual evapotranspiration for rice paddy which is already reported, value for crop coefficient may be 0.8 in local varities, 1.0 in Tongil varity on Blanney-Criddle formula, and 1.2 in local varities and 1.5 in Tongil varity on the mean of four other fomulas. 4. Five formulas may applied for calculation of potential evapotranspiration because of relatively good correlation among them. However Blanney-Criddle formula is one of recommendable ones, because it is easy to compute and requires less data in compare with other formulas.

• Korean Journal of Remote Sensing
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• v.30 no.4
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• pp.525-536
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• 2014

In this study, a method to assess and monitor hydrological drought using remote sensing was investigated for use in regions with limited observation data, and was applied to the Upper Namhangang basin in South Korea, which was seriously affected by the 2008-2009 drought. Drought information may be obtained more easily from meteorological data based on water balance than hydrological data that are hard to estimate. Air temperature data at 2 m above ground level (AGL) were estimated using remotely sensed data, evapotranspiration was estimated from the air temperature, and the correlations between precipitation minus evapotranspiration (P-PET) and streamflow percentiles were examined. Land Surface Temperature data with $1{\times}1km$ spatial resolution as well as Atmospheric Profile data with $5{\times}5km$ spatial resolution from MODIS sensor on board Aqua satellite were used to estimate monthly maximum and minimum air temperature in South Korea. Evapotranspiration was estimated from the maximum and minimum air temperature using the Hargreaves method and the estimates were compared to existing data of the University of Montana based on Penman-Monteith method showing smaller coefficient of determination values but smaller error values. Precipitation was obtained from TRMM monthly rainfall data, and the correlations of 1-, 3-, 6-, and 12-month P-PET percentiles with streamflow percentiles were analyzed for the Upper Namhan-gang basin in South Korea. The 1-month P-PET percentile during JJA (r = 0.89, tau = 0.71) and SON (r = 0.63, tau = 0.47) in the Upper Namhan-gang basin are highly correlated with the streamflow percentile with 95% confidence level. Since the effect of precipitation in the basin is especially high, the correlation between evapotranspiration percentile and streamflow percentile is positive. These results indicate that remote sensing-based P-PET estimates can be used for the assessment and monitoring of hydrological drought. The high spatial resolution estimates can be used in the decision-making process to minimize the adverse impacts of hydrological drought and to establish differentiated measures coping with drought.

• Journal of Biomedical Engineering Research
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• v.24 no.2
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• pp.133-140
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• 2003

In this study, muscle activity was measured using surface EMG (sEMG) during a voluntary maneuver (ankle dorsiflexion) in the supine position was compared pre and post gait training. Nine patients with incomplete spinal cord injury participated in a supported treadmill ambulation training (STAT), twenty minutes a day, five days a week for three months. Two tests, a gait speed test and a voluntary maneuver test, were made the same day, or at least the same week, pre and post gait training. Ten healthy subjects' data recorded using the same voluntary maneuvers were used for the reference. sEMG measured from ten lower limb muscles was used to observe the two features of amplitude and motor control distribution pattern, named response vector. The result showed that the average gait speed of patients increased significantly (p〈0.1) from 0.47$\pm$0.35 m/s to 0.68$\pm$0.52 m/s. In sEMG analysis, six out of nine patients showed a tendency to increase the right tibialis anterior activity during right ankle dorsiflexion from 109.7$\pm$148.5 $mutextrm{V}$ to 145.9$\pm$180.7 $mutextrm{V}$ but it was not significant (p〈0.055). In addition, only two patients showed increase of correlation coefficient and total muscle activity in the left fide during left dorsiflexion. Patients' muscle activity changes after gait training varied individually and generally depended on their muscle control abilities of the pre-STAT status. Response vector being introduced for quantitative analysis showed good Possibility to anticipate. evaluate, and/or guide patients with SCI, before and after gait training.

• Journal of dental hygiene science
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• v.6 no.4
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• pp.271-276
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• 2006

This study set out to analyze the relationships between the senior citizens' dental health activities and dental health conditions, to provide basic data to develop a program for their better dental health, and finally to search for the ways to improve their life quality through dental health care. The subjects were 142 senior citizens(58 were male and 84 were female) who were 65 years old or older and visited a dental hospital or clinic in the Seoul metropolitan area from April 17 to April 28, 2006. With the cooperation from the dentists, the investigators examined their dental conditions and conducted one-on-one interviews to collect the information about their demographic characteristics, dental health activities, and subjective dental health conditions. The collected data were analyzed with T-test, ANOVA and Pearson's correlation coefficient using the SPSS WIN 11.5 program. The analysis results were summarized as follows: First, 58 men(40.8%) and 84 women(59.2%) consisted of the subject group, where percentage of the female participants was bigger Those who were aged from 65 to 69 made the biggest age group in the subjects, accounting for 58.5% with 83. Second, those who had three dental caries or less and then didn't treat them or treated them(F) accounted for the biggest percentage with 117(82.4%) and 72(50.7%) respectively. As for the remaining teeth, the biggest number of them(40 subjects, 28.2%) had three or less remaining. Third, it turned out the female subjects had a higher level of dental health activities than their male counterparts(P = 0.00). As for living expenses, those who were paid salary or earned income themselves carried out their dental health activities in a higher level than those who lived on the benefit from the government(p = 0.02). Fourth, the subjects' subjective dental health conditions had negative correlations with their dental caries not treated. And there were positive correlations between their dental caries not treated and dental caries lost and between their dental caries treated and remaining teeth. Fifth, those subjects who earned their living expenses themselves had the most dental caries treated at 5.4(p = 0.02), and there was statistically significant difference with the numbers. Sixth, those subjects who brushed their teeth in their own manner had 11.8 teeth lost(p = 0.05), which was more than the number of those who brushed their teeth in other methods. And there was statistically significant difference among them. The remaining teeth were found most at 17.3(p = 0.00) among those who brushed their upper and lower teeth separately. In addition, those who visited the public health center often had significantly more teeth treated(4.3) than others(p = 0.00).

• Korean Journal of Agricultural and Forest Meteorology
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• v.8 no.3
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• pp.183-189
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• 2006

Six japonica and three Tongil type cultivars that were released in different years and planted to a large area during different periods were grown at the experimental farm of Seoul National University in 2001 and compared for traits related to dry matter production and grain yield. The varieties chosen were Jodongji released in 1896, Paldal in 1944, Jinheung in 1962, Nagdong and Tongil (Tonsil type) in 1971, Milyang#23 (Tongil type) in 1976, Hwasung in 1986, Ilpum in 1991, and Dasan (Tonsil type) in 1996. The more recent cultivars tended to have lower canopy light extinction coefficients (K). The K value was 0.601 in the oldest cultivar, Jodongji, and decreased below 0.5 in the cultivars released since 1971. Radiation use efficiency (RUE) was significantly different among cultivars before heading stage, showing no consistent tendency with the year of release and not significantly different after heading. Leaf area duration (LAD) was significantly different among varieties, and LAD values tended to be higher in the more recent cultivars. In particular, this tendency was more obscure in Tongil type cultivars. LAD of whole growth period had a significantly positive correlation with dry matter yield at harvest $(r=0.776^*)$. Dry matters measured at heading and harvest tended to be higher in recently released cultivars, but not significantly. The grain yield of Jodongji was the lowest but there was no significant difference among the other varieties in japonica, while higher yield occurred in the more recent Tongil type. Grain yield was correlated with grain number per square meter, and the more recent Tongil type cultivars had the greater grain number per square meter, In conclusion, not only the dry matter and grain yield but also related traits except K value showed no clear changes when compared with the year of their release in japonica cultivars. However, the increased grain yield in the more recent Tonsil type cultivars might have resulted from the enhanced LAD that lead to the higher dry matter production and in turn to the enlarged sink size.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.5
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• pp.2142-2147
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• 2012

This study is aimed at decreasing wrong diagnosis with corrected EF(Ejection Fraction) of 2D echo cardiography by analysing the physical time-resolution difference between Cine MRI and 2D echo cardiography and applying the corrected EF in 2D echocardiography. From February 2010 to December 2011, among the 110 patients who had undergone both 2D echo cardiography and cine MRI only 37 patient were selected suffering aortic valve regurgitation. ED, ES and SV were measured and EF was calculated in each system while normal ranges of Cine MRI and 2D echocardiography were compared to evauate misdiagnosis rate. The correlation of physical time resolution between 2D echocardiography and MRI was evaluated and the differences were corrected with linear regression coefficient which is derived from linear regression analysis. Blandt-Altman plot was used to evaluate the reliability of corrected 2D echo cardiography EF and compare the error among measured values. The values were compared with MRI normal range and misdiagnosis rate was measured again. As a result, misdiagnosis rates of physical time resolution were measured to be 32.4%(12people) before the correction of EF and 18.9%(7people) after the correction. Also, EF confirmed in Blandt-Altman plot were almost the same with MRI EF. In conclusion, when diagnosing aortic regurgitation disease, simply using 2D echocardiography can easily raise the misdiagnosis rates, therefore considering the MRI machine's physical merits, correcting the time resolution difference is important by calculating time resolution wrong diagnosis would decrease and it is considered to be useful in clinical circumstances.