• Korean Journal of Agricultural and Forest Meteorology
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• v.18 no.3
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• pp.135-142
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• 2016

The aim of this study was to confirm the improvement of efficiency for temperature estimation at 0600 and 1500 LST by using a simple method for estimating temperature lapse rate modulated by the amount of clouds in comparison with the case adopting the existing single temperature lapse rate ($-6.5^{\circ}C/km$ or $-9^{\circ}C/km$). A catchment of the 'Hadong Watermark2,' which includes Hadong, Gurye, and Gwangyang was selected as the area for evaluating the practicality of the temperature lapse rate estimation method. The weather data of 0600 and 1500 LST at 12 weather observation sites within the catchment were collected during the entire year of 2015. Also, the 'sky condition' of digital forecast products of KMA in 2015 ($5{\times}5km$ lattice resolution) were overlapped with the catchment of the 'Hadong Watermark2,' to calculate the spatial average value within the catchment, which were used to simulate the 0600 and 1500 LST temperature lapse rate of the catchment. The estimation errors of the temperatures at 0600 LST were ME $-0.39^{\circ}C$ and RMSE $1.45^{\circ}C$ in 2015, when applying the existing temperature lapse rate. Using the estimated temperature lapse rate, they were improved to ME $-0.19^{\circ}C$ and RMSE $1.32^{\circ}C$. At 1500 LST, the effect of the improvements found from the comparison between the existing temperature lapse rate and the estimated temperature lapse rate were minute, because the estimated lapse rate of clear days is not very different from the existing lapse rate. However, the estimation errors of the temperatures at 1500 LST during cloudy days were improved from ME $-0.69^{\circ}C$, RMSE $1.54^{\circ}C$ to ME $-0.51^{\circ}C$, RMSE $1.19^{\circ}C$.

• Journal of Nutrition and Health
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• v.51 no.5
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• pp.400-413
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• 2018

Purpose: This study examined the association between the antioxidant vitamin intake and obesity in Korean women. Methods: Adult women aged ${\geq}19years$ who completed a health examination and nutrition survey from the Korea National Health and Nutrition Examination Survey between 2007 ~ 2016 were selected for the study (n = 30,425). A BMI ${\geq}25kg/m^2$ and waist circumference ${\geq}85cm$ were defined as obesity and abdominal obesity, respectively. The individual antioxidant vitamin intake was estimated by linking the antioxidant vitamin composition database of commonly consumed foods and the subjects' 24-hour recall food consumption data. Carotenoids, retinol, vitamin A (retinol activity equivalent), vitamin C, tocopherols, and vitamin E (${\alpha}$-tocopherol equivalent) were included in the analysis. Each vitamin intake was converted to the nutrient density per 1,000 kcal. Odds ratio (ORs) and 95% confidence interval (CI) for obesity according to each tertile of the nutrient density was obtained from multiple logistic regression adjusted for age, household income, education level, smoking, alcohol consumption, and physical activity. Results: The mean intake of ${\alpha}$-carotene, retinol, vitamin E, ${\alpha}$-tocopherol, and ${\gamma}$-tocopherol per 1,000 kcal was significantly lower in the obese group than in the normal group. A higher intake of lycopene was inversely associated with obesity (highest vs. lowest; OR = 0.89, 95% CI: 0.83-0.96) and abdominal obesity (highest vs. lowest; OR = 0.88, 95% CI: 0.81-0.95). Higher intakes of ${\alpha}$-carotene, total carotenoids, vitamin A, and ${\gamma}$-tocopherol also had a negative relationship with abdominal obesity. The antioxidant vitamin intakes from eggs, milk and dairy products, seasoning, and grains were significantly lower in the obese group than in the normal group. Conclusion: This study showed that the dietary intake of antioxidant vitamins was inversely associated with obesity and abdominal obesity among Korean women. Further study will be needed to examine the causal relationship between the antioxidant vitamin and obesity.

• Journal of Distribution Science
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• v.9 no.2
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• pp.49-59
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• 2011

A franchise can be said to be the main method of distribution and marketing. It appears to be the future of the retail industry and is one of the world's fastest growing businesses sectors, as many policy reports and research results have acknowledged. Korea's franchise industry began in the 1970s, spread out into many areas (including food services, retail, and the service industry), and has grown by over 10% each year ever since. The industry's influence on the national economy becomes ever greater. Although the size of the franchise industry is expected to grow as it spreads and as the government expands its support, it has not yet attracted much academic interest. Research has so far been very fragmented. The main interest has been the relationship and conflicts between the head offices and the affiliates. No study has yet occurred on whether the concepts of satisfaction and intent to conclude a contract directly affect the success or failure of the affiliates. Few studies have empirically inquired into the demographic characteristics and abilities of the affiliates that significantly affect their results. Domestic franchise industries must prepare to leap from quantitative to qualitative growth. Most important is the need for affiliate headquarters and affiliates to build confidence between them. A friendly and reliable relationship between affiliate headquarters and affiliates will eliminate distrust from the franchise and maintain a healthy franchise system. This study suggests that current and prospective heads of affiliation should concentrate not on attracting affiliates but on investment and techniques of affiliate support. They should work on the reinforcement of brand power, the appropriate affiliate business environment, systematic education/training, taking burdens off the affiliate business persons, consolidating the relationship with the affiliate business persons, marketing mix factors (e.g. products, price conditions, logistics and shipping services, promotion, supervising and supervisor, operation procedures/processes, and material evidence); these all greatly affect the success or failure of the affiliate business. Supporting the affiliates is an important factor that enhances their results and satisfaction and consequently increases the positive recommendations to others and the ratio of recurrent conclusions of contracts, which ultimately generate the growth of the franchises. In addition, it is suggested that prospective franchise founders should make every effort to choose a good head office since the characteristics of the head office greatly influence the success of the affiliates. This study is significant in that it grasps the characteristics of the head office of affiliation and of the affiliates that influence affiliate results in ways not yet academically attempted.

• Korean Journal of Agricultural and Forest Meteorology
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• v.21 no.1
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• pp.29-41
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• 2019

Terrestrial Gross Primary Production (GPP) is the largest global carbon flux, and forest ecosystems are important because of the ability to store much more significant amounts of carbon than other terrestrial ecosystems. There have been several attempts to estimate GPP using mechanism-based models. However, mechanism-based models including biological, chemical, and physical processes are limited due to a lack of flexibility in predicting non-stationary ecological processes, which are caused by a local and global change. Instead mechanism-free methods are strongly recommended to estimate nonlinear dynamics that occur in nature like GPP. Therefore, we used the mechanism-free machine learning techniques to estimate the daily GPP. In this study, support vector machine (SVM), random forest (RF) and artificial neural network (ANN) were used and compared with the traditional multiple linear regression model (LM). MODIS products and meteorological parameters from eddy covariance data were employed to train the machine learning and LM models from 2006 to 2013. GPP prediction models were compared with daily GPP from eddy covariance measurement in a deciduous forest in South Korea in 2014 and 2015. Statistical analysis including correlation coefficient (R), root mean square error (RMSE) and mean squared error (MSE) were used to evaluate the performance of models. In general, the models from machine-learning algorithms (R = 0.85 - 0.93, MSE = 1.00 - 2.05, p < 0.001) showed better performance than linear regression model (R = 0.82 - 0.92, MSE = 1.24 - 2.45, p < 0.001). These results provide insight into high predictability and the possibility of expansion through the use of the mechanism-free machine-learning models and remote sensing for predicting non-stationary ecological processes such as seasonal GPP.

• Korean Journal of Soil Science and Fertilizer
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• v.39 no.5
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• pp.321-327
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• 2006

In Korea, there is a growing competitive for water resources between industrial, domestic and agricultural consumer, and the environment as many other OECD countries. The demand on water use is also affecting aquatic ecosystems particularly where withdrawals are in excess of minimum environmental needs for rivers, lakes and wetland habits. OECD developed three indicators related to water use by the agriculture in above contexts : the first is a water use intensity indicator, which is expressed as the quantity or share of agricultural water use in total national water utilization; the second is a water stress indicator, which is expressed as the proportion of rivers (in length) subject to diversion or regulation for irrigation without reserving a minimum of limiting reference flow; and the third is a water use efficiency indicator designated as the technical and the economic efficiency. These indicators have different meanings in the aspect of water resource conservation and sustainable water use. So, it will be more significant that the indicators should reflect the intrinsic meanings of them. The problem is that the aspect of an overall water flow in the agro-ecosystem and recycling of water use not considered in the assessment of agricultural water use needed for calculation of these water use indicators. Namely, regional or meteorological characteristics and site-specific farming practices were not considered in the calculation of these indicators. In this paper, we tried to calculate water use indicators suggested in OECD and to modify some other indicators considering our situation because water use pattern and water cycling in Korea where paddy rice farming is dominant in the monsoon region are quite different from those of semi-arid regions. In the calculation of water use intensity, we excluded the amount of water restored through the ground from the total agricultural water use because a large amount of water supplied to the farm was discharged into the stream or the ground water. The resultant water use intensity was 22.9% in 2001. As for water stress indicator, Korea has not defined nor monitored reference levels of minimum flow rate for rivers subject to diversion of water for irrigation. So, we calculated the water stress indicator in a different way from OECD method. The water stress indicator was calculated using data on the degree of water storage in agricultural water reservoirs because 87% of water for irrigation was taken from the agricultural water reservoirs. Water use technical efficiency was calculated as the reverse of the ratio of irrigation water to a standard water requirement of the paddy rice. The efficiency in 2001 was better than in 1990 and 1998. As for the economic efficiency for water use, we think that there are a lot of things to be taken into considerations to make a useful indicator to reflect socio-economic values of agricultural products resulted from the water use. Conclusively, site-specific, regional or meteorogical characteristics as in Korea were not considered in the calculation of water use indicators by methods suggested in OECD(Volume 3, 2001). So, it is needed to develop a new indicators for the indicators to be more widely applicable in the world.