• Journal of the Korean Recycled Construction Resources Institute
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• v.1 no.1
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• pp.8-16
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• 2013

Currently, global warming has advanced by the usage of fossil fuels such as coal and petroleum. and the atmosphere temperature in the world of 100 years(1906~2005) has been risen $0.74^{\circ}C{\pm}0.18^{\circ}C$, IPCC announced that the global warming effect of last decade was nearly doubled compared to the changes($0.07^{\circ}C{\pm}0.02^{\circ}C$/10year) in the past 100 years. Moreover, due to the global warming, heat wave, heavy snow, heavy rain, super typhoon, were caused and are increasing to happen in the world continuously causing damages and destruction of social infrastructures, where concrete structures are suffering deterioration by long-term extreme climate changes. to solve these problems, the new construction technology and codes are necessary. In this study, to solve these problems, experiments on a variety of cases considering the temperature and humidity, the main factors of climate factors, were performed, and the cases are decided by temperature and humidity. The specimens were tested in compressive strength test and split tensile test by the curing age(3,7,28 days) morever, performance based design(PBD) method was applied by using the satisfaction curve developed from the experiment date. PBD is the design method that gathers the current experimental analysis and past experimental analysis and develops the material properties required for the structure, and carries out the design of concrete mix, and it is recently studied actively worldwide. Also, it is the ultimate goal of PBD to design and perform on structures have sufficient performance during usage and to provide the problem solving for various situations, Also, it can achieve maximum effect in terms of functionality and economy.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.14
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• pp.123-131
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• 1973

1. In order to evaluate the performance of the $F_2$ and $F_3$ generations of $F_1$ varietal crosses which in past trials yielded better than or as high as the recommended double-cross hybrids, eleven yellow and five white-endosperm $F_1$ varietal crosses, their $F_2$ and $F_3$ generations, and the parental open-pollinated varieties together with the standard double-cross hybrids were tested in performance trials in the 1963 wet and 1963-64 dry seasons. The former trials, however, failed due to a strong typhoon that damaged the crop. 2. Net hybrid vigor was highly manifested in grain yield in the $F_1$ varietal crosses, which on the average was 39.9 per cent of the mid-parent yields. Reduction in heterosis was 27.2 per cent in the $F_2$and 30.3 per cent in the $F_3$ generation, respectively. 3. A fairly high degree of reduction in yield occurred in the $F_2$ and $F_3$ generation. On the average, the $F_2$ generation decreased by 17.6 per cent and the $F_3$ by 20.7 per cent. The losses in two generations were exhibited in two levels; four crosses decreased by 10.9 per cent and twelve combinations by 22.0 per cent. The advanced generations of one yellow cross, Cuban Yellow Flint ${\times}$ Hawaiian Flinty Dent, and three white flint crosses, Bicol White Flint ${\times}$ Eto Blanco, College White Flint ${\times}$ Eto Blanco and Bicol White Flint ${\times}$ Nariono 330b, yielded as high as Philippine Hybrid No.1 and Philippine Hybrid No.4, respectively. 4. No significant differences in yield were obtained between the $F_2$ and $F_3$ populations, showing that genetic equilibrium was reached in $F_2$, as may be expected in view of the Hardy-Weinberg law on panmixis. 5. As in past trials, Hawaiian Flinty Dent, a variety, yielded as high as Philippine Hybrid No. 1.

• Journal of Animal Science and Technology
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• v.48 no.3
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• pp.443-452
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• 2006

The four rice(Oryza sativa L.) lines, previously demonstrated to have vigorous herbage production at the vegetative growth stage, were investigated for their growth traits, dry matter yield and feed value using the twice-cutting system that 1st-cut is harvested at panicle formation stage and 2nd-cut at the yellow ripen stage. The twice-cutting system is regarded as an effective method in the production of forage rice by escaping lodging and insect damages caused by the overgrowth and typhoon around the heading stage.The feed value of the twice-cut rice plant of there lines were compared with the control of normal, cutting at the yellow ripen stage. The relative feed value(RFV), the total digestible nutrient(TDN) and the crude protein(CP) content of the twice-cut straw were higher the control in every lines. However, the dry matter yield (DMY), represented by the summed forage production of 1st and 2nd cut-rice plant, were lower the control, and the DMY of straws were increase but grains were decrease for twice-cutting system. In addition, TDN yield showed the similar tendency with DMY.Recently, as one of the breeding aims the researches for improving the digestibility of rice straw have been required. In this regard, twice-cutting system is recognized with the fact that it has the effect which raises the digestibility of the straw. Especially, the 2nd cut of IR73111-B-R-15-3-1 line was similar to the control at the TDN yield of straw, and would be used as a breeding material for product the roughage of good quality.

• Journal of the Society of Disaster Information
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• v.14 no.3
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• pp.238-246
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• 2018

Purpose: The purpose of this study is to examine the directions for establishing a disaster safety village in rural areas where damage from a similar type of disaster occurs repeatedly by conducting the consciousness survey targeting at experts and disaster safety officials in a local government. Method: The risks of disaster in rural areas were examined and the concept and characteristics of disaster safety village which is a measure on the basis of Myeon (township) among the measures of village unit were examined in order to carry out this study. In addition, opinion polling targeting at officials-in-charge in the local government and survey targeting at experts in disaster safety and building village were conducted. Based on the findings, the directions for establishing a disaster safety village that fitted the characteristics of rural areas were examined. Result: The officials-in-charge in the local government answered that rural areas have a high risk of storm and flood such as heavy snowing, typhoon, drought, and heavy rain as well as forest fire, and it is difficult to draw voluntary participation of farmers for disaster management activities due to their main duties. They also replied that active support and participation of residents in rural areas are necessary for future improvement measures. The experts mostly replied that the problem of disaster safety village project is a temporary project which has low sustainability, and the lack of connections between the central government, local governments and residents was stressed out as the difficulties. They said that measures to secure the budget and the directions of project promotion system should be promoted by the central government, local governments and residents together. Conclusion: The results of this study are as follows. First, a disaster safety village should be established in consideration of the disaster types and characteristics. Second, measures to secure the budget for utilizing the central government fund as well as local government fund and village development fund should be prepared when establishing and operating a disaster safety village in rural areas. Third, measures to utilize a disaster safety village in rural areas for a long period of time such as the re-authorization system should be prepared in order to continuously operate and manage such villages after its establishment. Fourth, detailed measures that allow residents of rural areas to positively participate in the activities for establishing a disaster safety village in rural areas should be prepared.

• Korean Journal of Heritage: History & Science
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• v.48 no.1
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• pp.24-43
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• 2015

This study constitutes an inquiry into the decline of Government Office(官衙) facilities carried out intensively during modern era, focusing on provincial government offices of Jeollabuk-do. There have been several studies of changes in provincial government offices till now, but there have been few studies of government offices of the counties and prefectures(郡縣) during the period of the Japanese Resident-General of Korea and after the National Liberation, temporally and there have still been lacking studies on Jeollabuk-do, spatially. Thus, this study attempts to empirically prove the reasons and the time of the decline of provincial government offices in Jeollabuk-do and the characteristics in the process of decline focusing on modern era. As a result of the study, four factors: demolition, abolition, appropriation and disaster had the most decisive impacts on the decline of government office facilities. Demolition refers to the destruction of government office facilities, and abolition, to the decline and the discontinuation of the operation of the facilities. Appropriation refers to conversion to facilities to meet public functions, and disaster, damage from a typhoon or fire. These factors had already been started from the 1900s, and by the 1930s, most of the government office facilities came to lose their original looks and functions. In the meantime, there was an essential purpose in demolition, the most direct factor in the destruction of the government office facilities in terms of function: that is new construction of public facilities necessary for administration and rule. The existing government office facilities were appropriated, sometimes, but behind that, many cases of demolition of the government office facilities for the new construction of public facilities are found. The appropriation of the government office facilities is divided into educational, administrative, financial and security facilities, and generally, Gaeksa(客舍) and Dongheon(東軒) were used respectively as educational and administrative facilities while their attached facilities were used as financial and public order and security facilities in general. Especially, some government office facilities were utilized as distinctive facilities such as housing or hospital. In the process of appropriation, a lot of modification occurred inside and outside the government office facilities, due to which, the government office facilities gradually declined losing their traditional styles.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.64 no.1
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• pp.40-47
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• 2019

This study was conducted to investigate the effect of planting density on plant growth, yield, and quality in the sweet sorghum cultivar 'Chorong' (Sorghum bicolor (L.) Moench). Plants were cultivated at densities of 16.7, 11.1, 8.3, 6.7, and $5.6plants{\cdot}m^{-2}$. Factors related to yield and yield components were analyzed using correlation and multivariate analyses. There was no significant difference among plant densities in stem length from 20 to 110 days after sowing. But the stem diameter was thin, and a decrease in number of tillers occurred more rapidly as planting density increased. At harvest, juice and sugar yield were higher at densities of 16.7 (42.9, $4.16Mg{\cdot}ha^{-1}$, respectively) and 11.1 (37.1, $3.73Mg{\cdot}ha^{-1}$) $plants{\cdot}m^{-2}$ than at 8.3 (30.5, $2.96Mg{\cdot}ha^{-1}$), 6.7 (26.6, $2.41Mg{\cdot}ha^{-1}$), and 5.6 (24.7, $2.22Mg{\cdot}ha^{-1}$) $plants{\cdot}m^{-2}$. The soluble solids and total sugar contents were not different among treatments, but relatively high values were observed at the density of 11.1 and $8.3plants{\cdot}m^{-2}$. As plant density was increased from 5.6 to $11.1plants{\cdot}m^{-2}$, the lodging index (1 = no, 9 = lodging) increased rapidly from 2.00 to 6.33. To determine the optimal planting density, the number of typhoons and topographical characteristics should be considered. Correlation and principal components analyses revealed that plant density exhibited a positive relationship with fresh stem yield ($r=0.62^{**}$), dry stem yield ($r=0.58^{**}$), juice ($r=0.63^{**}$), and sugar yield ($r=0.66^{**}$), but a negative with stem diameter ($r=-0.65^{**}$). The yield factors were not statistically related to stem height, diameter, and number of nodes.

• Journal of Korean Society of Disaster and Security
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• v.12 no.1
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• pp.11-21
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• 2019

This study assessed the risk of disaster by using QRE(Quick Risk Estimation - UNISDR Roll Model City of Basic Evaluation Tool) tools for three natural disasters and sixteen social disasters managed by the Seoul Metropolitan Government. The criteria for selecting 19 disaster types in Seoul are limited to disasters that occur frequently in the past and cause a lot of damage to people and property if they occur. We also considered disasters that are likely to occur in the future. According to the results of the QRE tools for disaster type in Seoul, the most dangerous type of disaster among the Seoul city disasters was "suicide accident" and "deterioration of air quality". Suicide risk is high and it is not easy to take measures against the economic and psychological problems of suicide. This corresponds to the Risk ratings(Likelihood ranking score & Severity rating) "M6". In contrast, disaster types with low risk during the disaster managed by the city of Seoul were analyzed as flooding, water leakage, and water pollution accidents. In the case of floods, there is a high likelihood of disaster such as localized heavy rains and typhoons. However, the city of Seoul has established a comprehensive plan to reduce floods and water every five years. This aspect is considered to be appropriate for disaster prevention preparedness and relatively low disaster risk was analyzed. This corresponds to the disaster Risk ratings(Likelihood ranking score & Severity rating) "VL1". Finally, the QRE tool provides the city's leaders and disaster managers with a quick reference to the risk of a disaster so that decisions can be made faster. In addition, the risk assessment using the QRE tool has helped many aspects such as systematic evaluation of resilience against the city's safety risks, basic data on future investment plans, and disaster response.

• Journal of Korea Water Resources Association
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• v.54 no.spc1
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• pp.1095-1105
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• 2021

The advancement of dam operation is further required due to the upcoming rainy season, typhoons, or torrential rains. Besides, physical models based on specific rules may sometimes have limitations in controlling the release discharge of dam due to inherent uncertainty and complex factors. This study aims to forecast the water level of the nearest station to the dam multi-timestep-ahead and evaluate the availability when it makes a decision for a release discharge of dam based on LSTM (Long Short-Term Memory) of deep learning. The LSTM model was trained and tested on eight data sets with a 1-hour temporal resolution, including primary data used in the dam operation and downstream water level station data about 13 years (2009~2021). The trained model forecasted the water level time series divided by the six lead times: 1, 3, 6, 9, 12, 18-hours, and compared and analyzed with the observed data. As a result, the prediction results of the 1-hour ahead exhibited the best performance for all cases with an average accuracy of MAE of 0.01m, RMSE of 0.015 m, and NSE of 0.99, respectively. In addition, as the lead time increases, the predictive performance of the model tends to decrease slightly. The model may similarly estimate and reliably predicts the temporal pattern of the observed water level. Thus, it is judged that the LSTM model could produce predictive data by extracting the characteristics of complex hydrological non-linear data and can be used to determine the amount of release discharge from the dam when simulating the operation of the dam.