• Korean journal of communication and information
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• v.18
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• pp.199-229
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• 2002

This study analyzed the trends of broadcaster licensing policy during 1990-2001 in Korea. It is to seek the answers about how the examination standards and procedures applied to broadcaster licensing has been changed for the last decade. For the purpose this study inquired six cases such as private broadcasting licence (1990 October), cable TV program provider licences(1993 July), cable TV system operator licences(1994 January), private local broadcaster licences(1994 July), satellite broadcaster licence(2000 December) and cable TV home shopping channel licences(2001 March). It examined the degree of specification and measurement of the standards based upon the government white paper; average points per item, average points per quantitative item, and average points per qualitative item etc. The government hadn't opened the standards and procedures how it licensed broadcasters until 1990 and the uncertain attitude brought distrust on the government broadcasting policy. The first white paper about broadcaster licensing was made in 1994 after cable TV broadcaster licensing was finished. The results indicated that Korean broadcasting licensing policy rapidly developed in the dimension of transparency from 'a secret room policy' to 'a sunshine policy' for the last decade. But it still needs improvement in the dimension of fairness of examination. Now one of the main distrust is the ratio that the one of qualitative examination standards are much more than the qualitative one.

• Journal of Korean Society of Forest Science
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• v.85 no.1
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• pp.15-23
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• 1996

Preparing the era of forest resources management requires studies on forest fire. This study attempted to develop forest fire occurrence model using meteorological characteristics for the practical purposes of forecasting forest fire danger rate. To accomplish this goal, the relationships between forest fire occurrence and meteorological characteristics are estimated. In the process, the forest fire occurrence pattern of the study region(Taegu-Kyungpook) is categorized by employing qualification IV method. The study region was divided into three areas such as, Taegu, Andong and Pohang area. The meteorological variables emerged as affective to forest fire occurrence are relative humidity, longitude of sunshine, and duration of precipitation. To estimate the probability of forest fire danger, forest fire occurrence of three areas are regressed on the time series data of affective meteorological variables using logistic and probit model. The effectiveness of the models estimated are tested and showed acceptable degree of goodness. Those models developed would be helpful to increase the efficiency of forest fire management such as detection of forest fire occurrence and effective disposition of forest fire fight equipments.

• Food Science and Preservation
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• v.13 no.5
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• pp.538-542
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• 2006

Physicochemical properties and positional distribution of Hallabong Tangor (Citrus Kiyomi ${\times}$ ponkan) cultivated in heated greenhouse were investigated. About 90% of Hallabong produce fruit within the range of $250{\sim}400g$ fruit weight on a tree, larger fruits were mainly consisted of $400{\sim}450g$ in M16A, a variant species of Hallabong, due to younger tree and fruit thinning. Nevertheless fruit sizes of M16A were larger than Hallabong, and peel thickness of M16A (3.29 mm) was thinner than that of Hallabong (3.51 mm). Hardness of m6h was 994.69g-force, compared to 832.8 g-force of Hallabong on the average. Soluble solids and acid content of Hallabong were $12.20{\sim}12.98^{\circ}Brix$ and $1.08{\sim}1.14%$, while those of M16A were $1.48{\sim}12.63^{\circ}Brix$ and $0.92{\sim}1.00%$, respectively. Vitamin C content of Hallabong was $71.30{\sim}78.77 mg/100 g$, compared to $64.40{\sim}68.01mg/100g$ in M16A. Soluble solid in the part of stem was lower than that of end part among the same segment. Fruit size in the upper part of the tree was larger, the peel was thicket and flesh ratio was lower than the middle or lower part. However, soluble solids and acid content were high, due to cumulative sunshine during cultivation.

• Journal of the Korean Society of Marine Environment & Safety
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• v.16 no.1
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• pp.31-41
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• 2010

Harmful dinoflagellate, Cochlodinium polykrikoides, has always occurred in southern coastal waters every year during summer, but it did not occur in 2009. A comparative study on outbreak in 2007/2008 and non-outbreak of C. polykrikoides in 2009 was performed based on environmental parameters and phytoplankton appearances. Samples were obtained at 13 stations from Yeosu to Wando waters in 2007-2009. The heavy rainfall was associated with the decrease of surface water temperature below $20^{\circ}C$ in July, the decrease of salinity below 31psu in August and increase of pH to 8.4 in Augus, 2009. concentration of DIN in 2009 was approximately too times as high as those of 2007 and 2008, and the ratioes of N:P and Si:N in 2009 showed Redfield ratio to be above the value of 16. This indicates that Redfield ratioes were significantly different between 2007/2008 and 2009. Dominant species during the field survey were shown to be Chaetoceros spp., Skeletonema costatum and Thalassiosir spp. in diatoms and to be Ceratium spp. in dinoflagellate. In partiuclar, Gonyaulax polygramma occurred in August, 2009 instead of C. polykrikoides. Consequently, the massive rainfall and shortage of sunshine contributed to considerable variation in environmental parameters which were associated with delay in the timing of rapid growth phase of C. polykrikoides.

• Korean Journal of Agricultural and Forest Meteorology
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• v.10 no.4
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• pp.113-120
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• 2008

The increase in average air temperature over the past 100 years in northern Asia including Korea is the greatest (about ${1.5}^{\circ}C$) among the various regions of the world. Considering a further warming projected by the IPCC, fluctuations of agro-climatic indices under climate change must precede an evaluation of vulnerability. The purpose of this study is to analyze how climate changes represented by global warming have altered agro-climatic indices in Korea over various time scales. Drought index during the rice-transplanting period of 15 May to 5 June has changed toward the favorable with recently increased precipitation in the Taebaek Alpine and Semi-Alpine Zone, and Yeongnam Basin and Inland Zone. The frequency of low temperature occurrence below $13^{\circ}C$ during the rice transplanting has decreased, while climatic production index (CPI) has fallen because of the decreased sunshine hour and increased temperature during the rice ripening period. We therefore concluded that the recent change of climate conditions was against the rice productivity in Korea.

• Journal of the Korea institute for structural maintenance and inspection
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• v.19 no.5
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• pp.45-55
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• 2015

Currently, extreme weather events such as super typhoon, extreme snowfall, and heat wave are frequently occurring all over the world by natural and human caused factors. After industrial growth in the 1970s, earth's temperature has risen sharply. due to greenhouse effect. Global warming can be attributed to gases emitted from using fossil fuel such as average carbon dioxide, perfluorocarbons, nitrous oxide, and methane. Especially, carbon dioxide has the highest composition of about 90%. in the fossile fuel usage emitted gas. Concrete has excellent durability as a building material climate change. However, due to various of physical and chemical environmental effect such as conditions during its curing process, the performance degradation may occur. Carbon dioxide in the atmosphere causes steel corrosion and durability decreases by lowering the alkalinity of concrete. Therefore, in this study, concrete durability performance with respect to carbonation from curing conditions change due to wind speed and sunshine exposure time. Concrete carbonation experiment are performed. using wind speed (0, 2, 4, 6) m/s and sunlight exposure time (2, 4, 6, 8) hrs. Also, performance based evaluation through the satisfaction curve based on the carbonation depth and carbonation rate test results are performed.

• The Korean Journal of Applied Statistics
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• v.29 no.2
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• pp.331-344
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• 2016

Whole Crop Barley (WCB) is a representative self-sufficient winter annual forage crop, along with Italian Ryegrass (IRG), in Korea. In this study, we examined the path relationship between WCB yield and climate factors such as temperature, precipitation, and sunshine duration using a structural equation model. A Bayesian approach was considered to overcome the limitations of the small WCB sample size. As prior distribution of parameters in Bayesian method, standard normal distribution, the posterior result of structural equation model for WCB, and the posterior result of structural equation model for IRG (which is the most popular winter crop) were used. Also, Heywood case correction in prior distribution was considered to obtain the posterior distribution of parameters; in addition, the best prior to fit the characteristics of winter crops was identified. In our analysis, we found that the best prior was set by using the results of a structural equation model to IRG with Heywood case correction. This result can provide an alternative for research on forage crops that have hard to collect sample data.

• Korean Journal of Construction Engineering and Management
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• v.20 no.6
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• pp.126-131
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• 2019

The estimation of available solar energy at particular locations is critical to find and assess suitable locations of PV sites. The amount of PV power generation is however affected by various geographical factors (e.g., weather), which may make it difficult to identify the complex relationship between affecting factors and power outputs and to apply findings from one study to another in different locations. This study thus undertakes a regression analysis using data collected from 172 PV plants spatially distributed in Korea to identify critical weather conditions and estimate the potential power generation of PV systems. Such data also include solar radiation, precipitation, fine dust, humidity, temperature, cloud amount, sunshine duration, and wind speed. The estimated PV power generation is then compared to the actual PV power generation to evaluate prediction performance. As a result, the proposed model achieves a MAPE of 11.696(%) and an R-squred of 0.979. It is also found that the variables, excluding humidity, are all statistically significant in predicting the efficiency of PV power generation. According, this study may facilitate the understanding of what weather conditions can be considered and the estimation of PV power generation for evaluating and determining suitable locations of PV facilities.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.64 no.3
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• pp.234-245
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• 2019

In order to select the best varieties and cultivation methods for the production of domestic wheat for Hodugwaja(a walnut shaped confection), we carried out a 3-year experiment (2015~2017) to investigate the effect of different factors (crop variety, planting date, nitrogen fertilization) in a double cropping system (wheat then rice) on crop yields in the Cheonan area. Rice is the second crop in the system, and requires an accumulated temperature for 40 days of about $840{\sim}930^{\circ}C$ to ensure ripening. Transplanting dates for rice between June 29 and July 6 were suitable; transplanting on or after July 13 does not ensure ripening. The daily hours of sunshine ranged from 6.3 to 6.5 hours, which were slightly higher than the optimum of 6.0 to 6.1 hours. The higher the nitrogen fertilizer treatment, the higher culm length, and spike length of wheat. The yield of wheat per 10a tended to increase as the amount of nitrogen fertilizer increased. Wheat yields were highest for the Sooan variety, followed by Goso, followed by Keumgang. The number of days from transplanting to heading of rice were shortest for the Jopyeong variety followed by Unkwang, followed by Haedam. The yield of milled rice per 10a increased as the transplanting date was earlier and the transplanting date of June 9 showed the average yield of more than 500 kg in three varieties. From the results of the experiment, we recommend the Goso wheat variety and the Haedam rice variety for growing in a double cropping system under the climatic conditions of the Cheonan area.

• Journal of Korea Water Resources Association
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• v.51 no.12
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• pp.1217-1227
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• 2018

This paper aims to evaluate the applicability of dam inflow prediction model using recurrent neural network theory. To achieve this goal, the Artificial Neural Network (ANN) model and the Elman Recurrent Neural Network(RNN) model were applied to hydro-meteorological data sets for the Soyanggang dam and the Chungju dam basin during dam operation period. For the model training, inflow, rainfall, temperature, sunshine duration, wind speed were used as input data and daily inflow of dam for 10 days were used for output data. The verification was carried out through dam inflow prediction between July, 2016 and June, 2018. The results showed that there was no significant difference in prediction performance between ANN model and the Elman RNN model in the Soyanggang dam basin but the prediction results of the Elman RNN model are comparatively superior to those of the ANN model in the Chungju dam basin. Consequently, the Elman RNN prediction performance is expected to be similar to or better than the ANN model. The prediction performance of Elman RNN was notable during the low dam inflow period. The performance of the multiple hidden layer structure of Elman RNN looks more effective in prediction than that of a single hidden layer structure.