• Korean Journal of Environmental Agriculture
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• v.15 no.2
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• pp.232-238
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• 1996

This study was conducted to find out the optimum condition for $NH_4-N$ removal from wastewater by a zeolite column. The removal efficiency of $NH_4-N$ by a glass column packed with decreased with the increase in initial concentration, percolation velocity and fraction number. The result of multiple stepwise regressions, $NH_4-N$ removal efficiency by the zeolite column showed a high correlationship with various parameters such as percolation velocity, initial concentration, adsorption amount and fraction number. Theoretical formula by parameter coefficients of multiple stepwise regression was found to be $NH_4-N$ removal $efficiency=0.620{\times}amount$ of zeolite $-0.456{\times}percolation$ velocity $-0.212{\times}initial$ concentration $-3.038{\times}fraction$ number+100.1 In the case of the $NH_4-N$ removal efficiency in cattle farming wastewater, the experimental data were nearly coincident with the theoretical formula.

• Korean Journal of Ecology and Environment
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• v.43 no.3
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• pp.349-355
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• 2010

This study aims at the augmentation of reliability of the long-term rainfall runoff model. To do so agricultural water uses are evaluated by analyzing the effects of small scale irrigational hydraulic structures on long term runoff processes and thereby rainfall-runoff model is modified considering them. As a result the simulation results of the sub-basins having more agricultural reservoirs than the others are disagreed with the observations. The 2nd quarter simulation results show similar trend to it. Especially the farming seasonal results of the drought year as the year of 2008 have many negative discharge values due to the lack of agricultural water uses. This result come from the water uses input data corresponding to not real water uses but water demands. In this study the formulas are derived to estimate the discharges and return ratios and the long term rainfall-runoff model is reformulated based on these. It is confirmed that the errors of the simulation results could be reduced by considering the effects of small scale irrigational hydraulic structures and the reliability of the simulation results improved greatly.

• Korean Journal of Remote Sensing
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• v.30 no.6
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• pp.797-807
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• 2014

The Sea Surface Temperature (SST) is one of the most important oceanic environmental factors in determining the change of marine environments and ecological activities. Satellite thermal infrared images can be effective for understanding the global trend of sea surface temperature due to large scale. However, their low spatial resolution caused some limitations in some areas where complicated and refined coastal shapes due to many islands are present as in the Korean Peninsula. The coastal ocean is also very important because human activities interact with the environmental change of coastal area and most aqua farming is distributed in the coastal ocean. Thus, low-cost airborne thermal infrared remote sensing with high resolution capability is considered for verifying its possibility to extract SST and to monitor the changes of coastal environment. In this study, an airborne thermal infrared system was implemented using a low-cost and ground-based thermal infrared camera (FLIR), and more than 8 airborne acquisitions were carried out in the western coast of the Korean Peninsula during the periods between May 23, 2012 and December 7, 2013. The acquired thermal infrared images were radiometrically calibrated using an atmospheric radiative transfer model with a support from a temperature-humidity sensor, and geometrically calibrated using GPS and IMU sensors. In particular, the airborne sea surface temperature acquired in June 25, 2013 was compared and verified with satellite SST as well as ship-borne thermal infrared and in-situ SST data. As a result, the airborne thermal infrared sensor extracted SST with an accuracy of $1^{\circ}C$.

• Journal of Korean Society of Rural Planning
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• v.20 no.2
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• pp.71-80
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• 2014

This study intended for Cheongryongsan Community Garden in Gwanak-gu, one of the demonstration places for 'Community Garden' Project recently implemented by the Seoul Government. This study had two major purposes: investigating the current status of the management and usage and identifying its characteristics; investigating users' awareness to consider the construction and operation directions of sustainable community gardens. This study was conducted based on several surveys such as an investigation into the spatial configuration and the management system of parks through a field study, a use survey through a questionnaire survey for vegetable garden users and an awareness survey about the construction direction of gardens direction preferred by users through the analytical hierarchy process (AHP). As a result of a questionnaire survey for vegetable garden users, the usage status was summarized as follows: Considering the common trends in the 2012 and the 2013 user survey, women used Cheongryongsan Vegetable Garden more than men. Over fifties used it most of all users. Users were mostly neighborhood residents. They used to visit there three to five times a week and stayed for about 30 minutes to one hour. Users differently responded to the question related to the order of priority for the use of the garden in the 2012 and the 2013 survey. They had increasingly used it for individuals' production activities more than social exchanges. As a result of making an AHP analysis for general park users, vegetable garden users there were clear differences in the targets which each subject put emphasis on in relation to the construction and operation of vegetable gardens. General park users recognized a vegetable garden as a park where park functions and the functions of the vegetable garden coexisted. On the other hand, vegetable garden users viewed it as a space where they attached importance to the functions of the vegetable garden like an allotment. Last, this study contemplated subjects related to the construction and operation of vegetable gardens which had to be considered in the future. Vegetable gardens tended to be biased as personal hobby places. It was viewed that the main reason was insufficient support activities for vegetable garden education and exchange programs originally planned when vegetable gardens had been constructed. Vegetable garden users recognized vegetable gardens as places for individuals' farming activities like allotments. For the desirable operation of vegetable gardens, it would be necessary to give priority to the park management before the production activities in individuals' vegetable gardens. The important role of the government would be to build the base through the provision of education and opportunities so that a local resident organization could actively participate in the management of a vegetable garden after a vegetable garden was constructed. It would be necessary to make a use survey and an awareness survey for users conducted in this study on a regular basis because the surveys could be important basic data in the decision-making process for the sustainable operations of the vegetable garden.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.12 no.5
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• pp.39-53
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• 2017

The purpose of this study was to investigate the effects of the rural migration factors, degree of preparation for migration, lifestyle conditions and support policies reflected against the family satisfaction of the migration. In this study family factors were used as control variables. Independent variables for this study will consist of the factors of rural migration, the degree of preparation for migration, living conditions of the farmers and the support policies, where as the dependent variable is the satisfaction of migration with an adjusting factor of the family satisfaction which will be further analysed to identify its effects on the dependent variable. For this study, a questionnaire survey was conducted for the residents and 237 valid questionnaires were collected. Multiple regression analysis was performed based on the collected data where demographic attributes being the controlling variable, and regression analysis was performed for the adjusting variable of the family. As the economic factor increases, the level of satisfaction generated to be higher in rural migration. As for the degree of preparation, living condition and support policies resulted, great quantity of green nature, safety and agriculture startup support, respectively, indicated a positive effect to the satisfaction level of migration. From the results, adjustment effect of the family factors on the economic, nature, convenience and satisfaction of the migration have appeared. The conclusion of this study is that policy support, regional stability, and economic gain are the most important factors to increase satisfaction and to reduce re-migration rate to city.

• Journal of Plant Biotechnology
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• v.37 no.3
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• pp.305-312
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• 2010

During a last decade, the introduced traits in commercialized GM crops have been diversified from a simple trait such as herbicide resistance gene or insectresistance gene which are related to the crop production into more complicated traits such as modification of fatty acid or essential amino acid composition, modified coloring pattern of flower. In addition, it was investigated that several other GM crops bearing more refined traits expected to lead next generation are also awaiting for risk assessment (RA) or under field test for the preparation of RA in the near future. These GM crops include abiotic stress resistance including drought or cold, increased biomass, production of bioethanol or diesel, production of pharmaceuticals or functional materials for industrial. In particular, in 2008 and 2009, it was reported that the highest number of GM crops for molecular farming are under developed in laboratory or green house level in all the world. Likewise, in Korea, 171 events from 49 plant species are under developed to introduce several important traits. At present, about 10 events are under field test to select elite lines for RA application. For the first time, herbicide resistance turfgrass developed by Korean research team has been submitted for RA and currently under requested for additional data. Moreover, GM rice resistant to leaf roll (folder) disease is expected as a next event to be submitted for RA application.

• Journal of Preventive Medicine and Public Health
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• v.43 no.6
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• pp.535-542
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• 2010

Objectives: Exposure assessment is a major challenge faced by studies that evaluate the association between pesticide exposure and adverse health outcomes. The objective of this study was to investigate the reliability of information that farmers self-report regarding their pesticide use. Methods: Twenty five items based upon existing questionnaires were designed to focus on pesticide exposure. In 2009, a selfadministrated survey was conducted on two occasions four weeks apart among 205 farmers residing in Gyeonggi and Gangwon provinces. For a reliability measure, we calculated the percentage agreement, the kappa statistics and the intraclass correlation coefficient (ICC) between the two reports according to the characteristics of the subjects. Results: Agreement for ever-never use of any pesticide was 96.4% (kappa 0.61). For both 'years used' and 'age at the first use' of overall pesticides, high agreement was obtained (ICC: 0.88 and, 0.78, respectively), whereas those of 'days used' and 'hours used' were relatively low (ICC: 0.42 and, 0.66, respectively). The kappa value for the use of personal protective equipment ranged from 0.46 to 0.59, and hygiene activities came out at 0.19 to 0.37. The agreement for individual pesticide use ranged widely and there was relatively low agreement due to the low response rates. The reliability scores did not significantly vary according to gender, age, the education level, the types of crop or the years of farming. Conclusions: Our results support that carefully designed, self-reported information on ever-never pesticide use among farmers is reliable. However, the reliability of data on individual pesticide exposure may be unstable due to low response rates and needs to be refined.

• Journal of Soil and Groundwater Environment
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• v.21 no.6
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• pp.179-191
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• 2016

In addition to the measurement of the concentration of soil contaminants, the new idea of indicative parameters was proposed to validate the remedial works through the monitoring for the changes of soil characteristics after applying the clean up technologies. The parameters like CFU (colony forming unit), pH and soil texture were recommended as indicative parameters for land farming. In case of soil washing, water content and the particle size distribution of the sludge were recommended as indicative parameters. The sludge is produced through the particle separation process in soil washing and it is usually treated as a waste. The parameters like water content, organic matter content, CEC (cation exchange capacity) and CFU were recommended as indicative parameters for the low temperature thermal desorption method. Besides the indicative parameter, sampling methods in stock pile and the optimal minimum amount of composite soil sample were proposed. The rates of sampling error in regular grid, zigzag, four bearing, random grid methods were 17.3%, 17.6%, 17.2% and 16.5% respectively. The random grid method showed the minimum sampling error among the 4 kinds of sampling methods although the differences in sampling errors were very little. Therefore the random grid method was recommended as an appropriate sampling method in stock pile. It was not possible to propose a value of optimal minimum amount of composite soil sample based on the real analytical data due to the dynamic variation of $CV_{fund{\cdot}error}$. Instead of this, 355 g of soil was recommended for the optimal minimum amount of composite soil sample under the assumption of ISO 10381-8.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.50 no.4
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• pp.238-246
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• 2005

Rice yield and protein content have been shown to be highly variable across paddy fields. In order to characterize this spatial variability of rice within a field, two-year experiments were conducted in 2002 and 2003 in a large-scale rice field of $6,600m^2$ In year 2004, an experiment was conducted to know if variable rate treatment (VRT) of N fertilizer, that was prescribed for site-specific management at panicle initiation stage, could reduce spatial variation in yield and protein content of rice while increasing yield compared to conventional uniform N topdressing (UN, 33kg N/ha at PIS) method. VRT nitrogen prescription for each grid was calculated based on the nitrogen (N) uptake (from panicle initiation to harvest) required for target rice protein content of $6.8\%$, natural soil N supply, and recovery of top-dressed N fertilizer. The required N uptake for target rice protein content was calculated from the equations to predict rice yield and protein content from plant growth parameters at panicle initiation stage (PIS) and N uptake from PIS to harvest. This model· equations were developed from the data obtained from the previous two-year experiments. The plant growth parameters for the calculation of the required N were predicted non-destructively by canopy reflectance measurement. Soil N supply for each grid was obtained from the experiment of year 2003, and N recovery was assumed to be $60\%$ according to the previous reports. The prescribed VRT N ranged from 0 to 110kg N/ha with an average of 57kg/ha that was higher than 33 kg/ha of UN. The results showed that VRT application successfully worked not only to reduce spatial variability of rice yield and protein content but also to increase rough rice yield by 960kg/ha. The coefficient of variation (CV) for rice yield and protein content was reduced significantly to $8.1\%$ and $7.1\%$ in VRT from $14.6\%$ and $13.0\%$ in UN, respectively. And also the average protein content of milled rice in VRT showed very similar value of target protein content of $6.8\%$. In conclusion the procedure used in this paper was believed to be reliable and promising method for reducing within-field spatial variability of rice yield and protein content. However, inexpensive, reliable, and fast estimation methods of natural N supply and plant growth and nutrition status should be prepared before this method could be practically used for site-specific crop management in large-scale rice field.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.11 no.1
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• pp.55-60
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• 1993

Forest occupied a part of natural ecosystem carries out a role of purifying air, preserving water resource, prevention of the breeding and extermination, recreation areas and etc that preserve and for me one's living environment. In this study, the classification for management of this forest is performed with Landsat TM Image. The classes are decided needle-leaf trees, broad-leaf trees, farming land and grass land, and water. When the TM digital images are classified on computer, water is represented in 7∼13 D.N. of 4th band. But the others is appeared similar mostly specific values so that must be done image processing. When the images compounded 2ed band and 3ed band are processed with ratio of enhancement. Needle-leaf treas is represented in l18∼136 D.N. of 1st band, broad-leaf trees in 72∼91 D.N. of 3ed band, farm land and glass land in 96∼120 of 3ed band. Forest Information is classified with M.L.C, an image classification method. The errors of needle-leaf trees, broad-leaf trees, farm land and grass land, and water are appeared each －7.43, ＋1.89,＋7.58 and －2.04 as compared the digital image with investigation on the scene. Finally, these results are useful for classification of forest vegetation with Landsat TM Image.