• Korean Journal of Soil Science and Fertilizer
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• v.43 no.6
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• pp.793-797
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• 2010

The investigations were conducted to improve the physical properties by analyzing physico-chemical properties on the different soil families of textures at 20 upland fields located in the parts of Gyengsangbuk-do area. Soil physico-chemical properties were analyzed for bulk density, hardness, porosity, moisture, pH, EC and organic mater by soil depth on the different soil families of textures. Bulk density distributions were higher than 1.2 Mg $m^{-3}$ in the optimum range. Hardness distributions were lower than 20 mm in the optimum range. Therefore, the physical properties of upland soil was deteriorated. Correlation coefficient of bulk density with hardness and organic mater were higher significantly, that was positive and negative, respectively. The soil hardness had the greatest distribution degree to the crop yield and bulk density and organic matter followed. Conclusively, To improve the physical properties of upland soil was more effective to fertilizing organic matter than other ways.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.43 no.4
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• pp.485-492
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• 2023

Among the methods to improve traffic congestion by providing real-time traffic information and solving problems like traffic congestion and traffic crashes, private enterprise is implementing policies to lower insurance premiums like compensation for drivers' driving safety scores. Despite the emergence of various incentive policies, a study on the level of incentive payment for safe/eco-friendly driving is insufficient. The research analyzed the satisfactory factors that affect the scale of incentives through questionnaires and the applicable scale of incentives that enable safe/eco-friendly driving using a binary logistic regression model. As a result of analyzing the incentive scale of the appropriate payment amount for each driving score increase, 0.4% of the toll fee was derived when the driving score increased by 20 points, and 0.5% of the toll fee was derived when the driving score increased by 30 points. This study on calculating the appropriate incentive payment scale for driver information sharing and driving score increase will help optimize incentives and prepare system implementation plans.

• Journal of Korean Society of Forest Science
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• v.76 no.3
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• pp.181-192
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• 1987

The purpose of this study is to develop the method of stand volume estimation by the plotless sampling method. The required data were obtained from 164 sampling plots in the red pine(Pinus densiflora) stands which were located in Kyeong-gi, Chung-nam, Chung-buk and Kang-won areas, and related factors were measured actually. The method of stand volume estimation and several tables were drivel from these data. 1. The relationship between the values of stand average height, basal area per ha, and basal area height obtained from the plotless sampling method and values measured actually could be described by the equation Y=bx, where b approached nearly 1.0 and there were no significant differences between them. Therefore stand volumes could be estimated by the plotless sampling method. 2. The estimated equations of the stand voulumes, which were estimated using factors to be measured by dendrometer, are as follows ; logV=-0.0208+0.8497 logGH, logV=-0.0028+0.7981 logG+0.9313 logH. Stand volume tables by these estimated equations were shown in table 4, 5 and estimation error percentages were 9.16% and 8.50% respectively. FH=D/(1.5205+0.0994D) logFH=0.0451+0.2429 logD+0.3474 logH logFG=-0.0380+0.7758logG-0.0066logH F=H/ (-5.1697+2.6013H) F=FH/(-3.1256+2.7611FH) logF=-0.0634-0.0848 logGH-0.1224 logDi 4. Stand form height tables(table7, 8), form basal area tables(table 9), and stand form factor tables(table 10, 11) were prepared using the above estimated equations, and the estimation error percentages were less than 10%.

• Korean Journal of Agricultural and Forest Meteorology
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• v.11 no.2
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• pp.72-78
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• 2009

The demand for rainfall data in gridded digital formats has increased in recent years due to the close linkage between hydrological models and decision support systems using the geographic information system. One of the most widely used tools for digital rainfall mapping is the PRISM (parameter-elevation regressions on independent slopes model) which uses point data (rain gauge stations), a digital elevation model (DEM), and other spatial datasets to generate repeatable estimates of monthly and annual precipitation. In the PRISM, rain gauge stations are assigned with weights that account for other climatically important factors besides elevation, and aspects and the topographic exposure are simulated by dividing the terrain into topographic facets. The size of facet or grid cell resolution is determined by the density of rain gauge stations and a $5{\times}5km$ grid cell is considered as the lowest limit under the situation in Korea. The PRISM algorithms using a 270m DEM for South Korea were implemented in a script language environment (Python) and relevant weights for each 270m grid cell were derived from the monthly data from 432 official rain gauge stations. Weighted monthly precipitation data from at least 5 nearby stations for each grid cell were regressed to the elevation and the selected linear regression equations with the 270m DEM were used to generate a digital precipitation map of South Korea at 270m resolution. Among 1.25 million grid cells, precipitation estimates at 166 cells, where the measurements were made by the Korea Water Corporation rain gauge network, were extracted and the monthly estimation errors were evaluated. An average of 10% reduction in the root mean square error (RMSE) was found for any months with more than 100mm monthly precipitation compared to the RMSE associated with the original 5km PRISM estimates. This modified PRISM may be used for rainfall mapping in rainy season (May to September) at much higher spatial resolution than the original PRISM without losing the data accuracy.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.7
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• pp.3326-3337
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• 2013

This study was performed to determine health-related dietary and lifestyle of characteristic factors associated with sodium hyperingestion of korean adults by sexual difference. Study subjects were 30~69years (n=1,622) adults who participated in the 2010 Korean National Health and Nutrition Examination Survey (KNHANES V-1). Subjects were divided into the hyperingestion group (HG, n=1,494) and normal ingestion group (NG, n=128) by 'WHO growth standard sodium intakes(2,000mg/day)' and the relationships between Comparison of demographics and physical measurement, eating behaviors and health-related factors were analyzed. By logistic regression method, risk factors for sodium hyperingestion group revealed in this study were gender(female), number of family', 'breakfast', 'lunch', 'dinner', 'nutrition labeling use'. and In case of male, risk factors for sodium hyperingestion group were 'lunch', 'dinner', 'self-rated body image' of eating behaviors. In case of female, Which were number of family' of demographics, 'breakfast', 'lunch', 'dinner' of eating behaviors. In these results, according to different sexual aspect of sodium hyperingestion, we suggest that nutrition label use and proper nutrition intake criteria among sexual, recognition promotion campaign along with education program for repressed sodium hyperingestion related to hypertension prevention of korean adults should include eating habits improvement and demographics lifestyle modification.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.11
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• pp.5578-5586
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• 2012

The accurate estimation of discharge is very essential as the important factor of river design for the utilization and flood control, hydraulic construction design. The present discharge production is using the stage-discharge relationship curve in the river. The rating curve uses the method by predicting the discharge based on regression analysis using the measured stage and discharge data in a flood season. The method is comparatively convenient and has especially advantages in that it can predict the discharge having the difficulty of observation in a flood season. However, this method has basically room for improvement because the method only uses the relationship between stage and discharge, and doesn't reflect the hydraulic parameters such as hydraulic radius, energy slope, roughness, topography, etc.. Therefore, in this study, discharge was predicted using the convenient calculation method with empirical parameters of the Manning and Chezy equations, which were proposed by Choo et at (2011) in KSCE as a new methodology for estimating discharge in open channel. The proposed method can conveniently estimate empirical parameters in both of Manning and Chezy equations and the discharge is estimated in the open channels. There are proved by using data measured in meandering lab. channel and India canal and the accuracies show about determination coefficient 0.8. Accordingly, this method will be used in actual field if this study is continuously conducted.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.15 no.3
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• pp.45-51
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• 2016

Existing real-time signal control system was brought up typical problems which are supersaturated condition, point detection system and loop detection system. For that reason, the next generation signal control system of advanced form is required. Following thesis aimed at calculating queue length for the next generation signal control system to utilize basic parameter of signal control in crossing queue instead of the volume of real-time through traffic. Overflow saturated condition which was appeared as limit of existing system was focused to set-up range. Real-time location information of individual vehicle which is collected by GPS data. It converted into the coordinate to apply shock wave model with an linear equation that is extracted by regression model applied by a least square. Through the calculated queue length and link length by contrast, If queue length exceed the link, queue of downstream intersection is included as queue length that upstream queue vehicle is judeged as affecting downstream intersection. In result of operating correlation analysis among link travel time to judge confidence of extracted queue length, Both of links were shown over 0.9 values. It is appeared that both of links are highly correlated. Following research is significant using real-time data to calculate queue length and contributing to signal control system.

• Journal of Nutrition and Health
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• v.50 no.4
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• pp.383-390
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• 2017

Purpose: This study investigated the importance and performance of food/nutrition labeling. The aim was to determine how important students consider food nutritional labeling, utilization of nutrition labels in daily life, and consumer satisfaction of current nutritional labeling. Methods: This study was conducted using a primary survey of students at one high school in Seoul. A total of 300 of 382 questionnaires were analyzed. Results: Regarding difference analysis of the importance-performance of food/nutrition labeling, importance showed higher scores than performance in all 10 attributes. According to the results of Importance and Performance Analysis (IPA), 'health, weight control and maintenance, proper dietary habits, and personal satisfaction' displayed both high importance and performance in the first quadrant. Importance of two factors (health and nutritional factor and effects of media and education) of the 10 attributes positively influenced overall satisfaction in the multiple regression analysis. Conclusion: To develop healthier food choices, it is necessary to educate adolescents about food/nutrition labeling and improve the food/nutrition labeling system.

• Korean journal of applied entomology
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• v.50 no.4
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• pp.289-293
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• 2011

This study was conducted to develop economic injury level (EIL) of onion thrips, Thrips tabaci, on welsh onion (Allium fistulosum L. var) in the early transplanting stage. The changes of welsh onion biomass, yield loss, and T. tabaci density were investigated according to the inoculation periods of T. tabaci. In the early transplanting stage of welsh onion, the yield loss (%) increased with increasing inoculation periods: 17.0, 53.3, 38.4, and 80.8% yield loss in 5, 10, 15, and 20 d inoculation periods, respectively. The relationship between Cumulative Insect Days (CID) of T. tabaci and yield loss (%) of welsh onion was well described by a nonlinear logistic equation. Using the estimated equation, EIL of T. tabaci on welsh onion was estimated to 30 CID per plant based on the yield loss 12% (an empirical gain threshold 5% + marketable rate 93% of welsh onion). ET was calculated to 24 CID, which corresponds to 80% of EIL. Until a more defined EIL-model is developed, the present results should be useful for T. tabaci management in early growth stage of welsh onion. The effect of T. tabaci attack on the yield of welsh onion in late growing season (120 days after transplanting) was also examined. The yield of welsh onion increased at a low population density of T. tabaci and decreased at higher densities, showing a typical over-compensatory response.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.7
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• pp.4668-4678
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• 2015

This study was conducted to determine the correlation between breakfast consumption and health-related quality of life in elderly adults. It analyzed the data from the National Health and Nutrition Examination Survey from 2010 to 2012, using a sample of 4,035 people aged 65 or above. Analysis followed the SAS SURVEY procedure, considering the complex sample design. A t-test, a chi-square test, and logistic regression analysis were performed using SAS version 9.3. The rate of skipping breakfast by elderly adults was 4.7%, and it was higher in women and elderly adults living alone. It also significantly differed by drinking status and BMI. Elderly adults consuming breakfast had slightly higher scores on the health-related quality of life measure than those who did not (0.85 vs 0.81). Results revealed that health-related quality of life increased with meal frequency, and that elderly adults who ate breakfast tended to score better on the pain/discomfort and anxiety/depression domains of the health-related quality of life measure. It was found that breakfast consumption associated with health-related quality of life in elderly adults. Accordingly, it is necessary to increase awareness among elderly adults regarding the importance of breakfast, and to improve their health-related quality of life by developing and implementing interventions to improve dietary habits.