• Magazine of the Korean Society of Agricultural Engineers
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• v.17 no.1
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• pp.3627-3641
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• 1975

The Government is trying to increase total food grain yield to meet national self sufficiency by means of increasing unit yield as well as extending crop land, and this year he set the target of 321,000 hectare of forest to clear for cropping. This study was carried to investigate the most efficient method of clearing hillock by bulldozer, and successful method to develope yielding potential of newly cleared land in short term. Since the conventional land clearing method is just earth leveling and root removing neglecting top soil treatment, the growth of crop was poor and farmer tends not to care the land. The top-soil-furrowing method is applied through out this study, that is advantageous especially for the land having shallow top soil and low fertility like Korean forest. In this study, various operating method were tried to find out most efficient method separately in connection with the land slope less than 25 percent and over, and several fertilizing methods to develop yielding potential. The results are as follows; 1) For the natural land slope utilization method, applicable to the land having less than 25 percent slope, reverse operating was more efficient than using forward gear of bulldozer. The operating time was 3 hour 32 minutes and 36 seconds using forward gear was 2 hour 32 minutes and 30 seconds for reverse gear operation per 1,000 square meter. 2) Bulldozer having angle blade adjustment needed 7hr 15min. for constructing of terrace per 10a compaire with the one having angle & tilt adjustment needed 6hr 4min for same operations. Specially there is significant difference for operation time of first period (earth cutting) such as bulldozer having angle blade adjustment needed 3hr 56min compaired with the one having angle & tilt adjustment 3hr 59min. In construction of terrace, the bull-dozer having tilting and angle blade adjustment was most suitable and performed efficiently. 3) For the fertilizer application treatment, the grass (Ladino clover) yield in first year was almost same as ordinary field's in the plot applied(N.P.K+lime+manure) while none fertilizer plot showed one tenth of it, and (N.P.K.+lime) applied plot yielded on third. 4) The effect of different land clearing method to yield showed significant difference between each treatment especially in the first year, and the conventional method was the lowest. In the second year, still conventional terracing plot yielded only half of ordinary field while the other plots showed as same as ordinary field's. 5) The downward top soil treatment plot showed most rapid improvement in soil structure during one year physio chemically, it showed increase in pH rate and organic composition, and the soil changed gradually from loam to sand-loam and the moisture content increased against the pF rate, and it gives good condition to grow hay due to the increase of field water capacity with higher available water content. 6) Since the soil of tested area was granite, the rate of soil errosion was increased about 2 to 5 percent influencing in soil structure more sand reducing clay content, and an optimum contour farming method should be prepared as a counter measure of errosion.

• Land and Housing Review
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• v.4 no.1
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• pp.65-75
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• 2013

The residential environment of old and deteriorated public rental housing has been improved for preventing house deterioration through the facility improvement projects during the recent three years. The purpose of this study is to check the effect of applied facility improvement projects through a survey to residents on the significance degree of improving the residential environment and the satisfaction degree of current residential environment. Moreover, this study aims to draw out the direction of the residential environment improvement. At first, for this purpose, a survey to the residents of old and deteriorated public rental housing in the country was conducted. In addition, the mean value analysis on the satisfaction degree and significance degree was done, and the factor analysis was conducted for the distinction between types of items. As a result, 29 items of residential public space for residential environment improvement were divided into six factors and 28 items for generation of each units were divided into four factors. The mean value of the satisfaction degree and significance degree was compared. In conclusion, the design direction of environment improvement projects in the future was suggested with the result of the survey.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.10 no.4
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• pp.54-69
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• 2007

The objective of study is to propose theoretical basis for applying planning elements to Environment-friendly Public Land Development in integrated perspective of 'eco' and 'health'. For this purpose, First, the definition of 'Environment-friendly Public Development' and the interrelation between 'eco' and 'heath' as the component element of it are proposed. Secondly, based on internal and external case studies, eco and health related planning elements are deprived. And to assess the planning elements efficiently, representative planning elements are selected by each content. Thirdly, based on the analysis of specialist question, how the selected planning elements contribute to the improvement of human health and ecosystem is assessed. The result of study could be useful to reflect the regional condition and to predict the effect of the application.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.39 no.2
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• pp.175-179
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• 1994

This experiment was carried out to investigate the effect of improved NPK fertilizer and ameliorator application methods on job's tears yield and soil properties in the newly-reclaimed land from 1985 through 1988. Job's tears height of integrated improvement plot was higher than the other plots, and increased from the 1st and the 2nd year, but decreased from the 3rd year when soil conditioner was not applied. Average yield of the crop in the integrated improvement plot was 2.16 t /ha being increased by 49% more than the control plot, and the yield was the greatest in order of integrated improvement>subsoiling>phosphate>lime>compost>control plot. Soil bulk density and hardness of the topsoil decreased to the 3rd year, but increased in the 4th year. Soil pH of the topsoil was not changed significantly by different soil depths and cultivated years.

• Atmosphere
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• v.28 no.4
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• pp.427-441
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• 2018

This study examines the impact of the urban parameterization scheme and the land cover change on simulated near surface temperature using Unified Model (UM) over the Seoul metropolitan area. We perform four simulations by varying the land cover and the urban parameterization scheme, and then compare the model results with 46 AWS observation data from 2 to 9 August 2016. Four simulations were performed with different combination of two urban parameterization schemes and two land cover data. Two schemes are Best scheme and MORUSES (Met Office Reading Urban Surface Exchange Scheme) and two land cover data are IGBP (International Geosphere and Biosphere Programme) and EGIS (Environmental Geographic information service) land cover data. When land use data change from IGBP to EGIS, urban ratio over the study area increased by 15.9%. The results of the study showed that the higher change in urban fraction between IGBP and EGIS, the higher the improvement in temperature performance, and the higher the urban fraction, the higher the effect of improving temperature performance of the urban parameterization scheme. 1.5-m temperature increased rapidly during the early morning due to increase of sensible heat flux in EXP2 compared to CTL. The MORUSES with EGIS (EXP3) provided best agreement with observations and represents a reasonable option for simulating the near surface temperature of urban area.

• Journal of Korean Society on Water Environment
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• v.34 no.3
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• pp.308-315
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• 2018

SWMM-LID was calibrated with flow monitoring data in LHI to evaluate runoff after LID application. The flow rate in the B basin was estimated to be 0.94 and 6.15 for O/S and $D_v$, respectively. In the A and C basins, the difference between the observed and simulated data was greater than in the B basin. As a result of runoff reduction efficiency by the application of LID facilities, the change of infiltration increased from 34.6 % to 45.8 % in the entire watershed, and the runoff decreased from 58.8 % to 46.3 %. In the runoff reduction of each LID facility, rain garden E showed the highest effect with 99.9 % and bioretention B showed the lowest effect with 27.5 %. In order to evaluate the efficiency of each LID facility, a comparison is made between the pore volume (V) of the LID and the catchment area (A). The runoff showed a runoff reduction effect of about 70 % above the 0.1 volume/area (V/A) value. As a result of examining the runoff reduction with LID facilities by the LID module of SWMM, a reasonable design is possible by reflecting the appropriate LID volume to drainage area.

• Journal of The Korean Society of Agricultural Engineers
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• v.57 no.3
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• pp.87-92
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• 2015

Cultivation on reclaimed tidal land is often difficult in the problem such as high salinity of soil, bad drainage because of high level of groundwater. Many researches have been made efforts to solve these problems, but effect of improvement is low and practicality is insufficient. In this study, through numerical analysis of the transport properties of salt and water, we suggested underground drainage of the reclaimed land and the desalination promotion methods in the soil. The results of characteristic of desalination and seepage analysis of underdrain show that underdrain is able to increase twice of the underground seepage amount when installing perforated pipe with horizontal filter (width 50cm) more than installing only the perforated pipe. For soil which coefficient of permeability is below $1{\times}10^{-4}cm/s$ that desalination with pond water is not possible, a method to increase the permeability of the soil is necessary. Therefore, it was concluded that application of underdrain using perforated pipe with horizontal filter would be low-cost and practical.

• The Journal of the Korea institute of electronic communication sciences
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• v.9 no.4
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• pp.515-526
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• 2014

In this study, the 'preservation of Jeonju Hanok Village Improvement Project' in earnest in promoting itself as the official land price changes in Jeonju Hanok Village and surrounding area thereby affect land prices to some extent in order to identify the time series analysis, t-black dispersion analysis showed the following results were obtained. First, time series analysis, and the Hanok Village, but the average official land price rises, and the area has been stead ilyrising. Second, the time series of the Official price year-over-year change in the average rate of the Hanok Village(+)rising, and the area is a gentle rise sooner or later (+)is expected to be an increase in conversion. Third, the number of tourists visiting Jeonju Hanok Village and sharply increased since 2008, was. Fourth, in order to use local official land price rises in the commercial area of highest priority that requires strategy was analyzed.

• Journal of Korean Society of Rural Planning
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• v.24 no.3
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• pp.73-86
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• 2018

Agricultural or rural landscape provides various ecosystem services. However, the ecosystem services function is declining due to various environmental problems such as climate change, land use change, stream intensification, non-point pollution and garbage. The A1B scenario predicts that the mean air temperature of South Korea will rise $3.8^{\circ}C$ degrees celsius in 2100. Agricultural sector is very vulnerable to climate change, so it must be thoroughly predicted and managed. In Korea, the facility horticulture complex is 54,051ha in 2016 and is the 3rd largest in the world(MAFRA, 2014). Facilities of horticultural complexes are reported to cause problems such as groundwater decrease, vegetation and insects diversity reduction, landscapes damage and garbage increase, compared with the existing land use paddy fields. Heat island phenomenon associated with climate change is also accelerated by the high heat absorption of horticultural sites. Therefore, we analyzed the heat island phenomenon occurring in the facility of horticultural complex in Korea. As an improvement measurement, I examined how much air temperature is reduced by putting the channel and the open space. In the case of the Buyeo area, the Computational Fluid Dynamics (CFD) simulation was analyzed for the average summer temperature distribution in the current land use mode at $38.9^{\circ}C$. As an improvement measurement, CFD simulation after 10% of 6m water channel was found to have an effect of lowering the summer temperature of about $2.7^{\circ}C$ compared with the present average of $36.2^{\circ}C$. In addition, CFD simulations after analyzing 10% of the open space were analyzed at $34.7^{\circ}C$, which is $4.2^{\circ}C$ lower than the present. For the Jinju area, CFD simulations were analyzed for the average temperature of summer at $37.8^{\circ}C$ in the present land use pattern. As an improvement measure, CFD simulations after 10% of 6m water channel were found to have an effect of lowering the summer temperature of about $2.6^{\circ}C$ compared to the current average of $35.2^{\circ}C$. In addition, CFD simulations after analyzing 10% of the open space were analyzed at $33.9^{\circ}C$, which is $3.9^{\circ}C$ lower than the present. It can be said that the effect of summer temperature drop in open space and waterway has been proven. The results of this study are expected to be reflected in sustainable agriculture land use and used as basic data for government - level policy in land use planning for climate change.

• Proceedings of the Korean Geotechical Society Conference
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• 2010.09a
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• pp.467-472
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• 2010

Individual vacuum pressure method is soft ground improvement technique, in which a vacuum pressure can be directly applied to the vertical drain board to promote consolidation and strengthening the soft ground. This method does not require a surcharge load, different to embankment or pre-loading method. In this study, given the inner displacement of the ground where the individual vacuum pressure is applied, this dissertation aimed to reproduce the state of stress in the ground that is subject to the constraints created by the depth of improvement area. Modified Cam Clay theory which made it possible to take into account the isotropic displacement of the ground was applied to the NAP-IVP used simulation; the conception of equivalent permeability proposed by Hird was also applied so that the 3-dimensional real construction effect of drain materials could be reflected in the analysis.