• Korean Journal of Remote Sensing
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• v.35 no.5_1
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• pp.637-647
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• 2019

The detection of crop stress is an important issue for the accurate assessment of yield decline. The photochemical reflectance index (PRI) was developed as a remotely sensed indicator of light use efficiency (LUE). The PRI has been tested in crop stress detection and a number of studies demonstrated the feasibility of using it. However, only few studies have focused on the use of PRI from remote sensing imagery. The monitoring of PRI using drone and satellite is made difficult by the low spectral resolution image captures. In order to estimate PRI from multispectral sensor, we propose a band fusion method using adjacent bands. The method is applied to the drone-based hyperspectral and multispectral imagery and estimated PRI explain 79% of the original PRI. And time series analyses showed that two PRI data (drone-based and SRS sensor) had very similar temporal variations. From these results, PRI from multispectral imagery using band fusion can be used as a new method for evaluation of crop stress.

• Korean Journal of Soil Science and Fertilizer
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• v.40 no.1
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• pp.43-50
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• 2007

Veterinary antibiotics have been widely used to increase feed efficiency, to prevent disease, and to promote growth as well as to control disease. The antibiotics administered can be excreted through the urine and feces. One of the major routes of veterinary antibiotics entering soil and water environment is via the application of animal manure to agricultural land as an organic fertilizer source. Since little is known about impacts of antibiotics on the environment, this study was conducted to prioritize the veterinary antibiotics based on the consumption and potential to reach the environment. Among 83 veterinary antibiotics consumed in Korea, ten antibiotics were used at the greater dose than 25 Mg in 2004. Potential to reach the environment was determined according to excretion rate after administered to animals and sorption affinity to soil solids after applied to agricultural land. Seventeen antibiotic active ingredients (Ais) were classified as 'High' priority in terms of the potential to reach the environment. An overall priority score was determined by combining priority score based on consumption with the degree of potential environment exposure. Twenty veterinary antibiotic AIs were classified as 'Very high' or 'High' priority requiring detailed assessment. The antibiotic AIs were identified four aminoglycosides, two macrolides, two penicillins, five sulfonamides, three tetracyclines, two quinolones, and two miscellaneous. Eight veterinary antibiotic AIs including amoxicillin, carbadox, chlortetracycline, neomycin, oxytetracycline, sulfamethazine, sulfathiazole, and tylosin were identified to have a greater priority of environmental risk in Korea.

• Journal of Korean Society of Forest Science
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• v.110 no.4
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• pp.622-629
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• 2021

This study analyzed the running speed of logging trucks (25 tons), depending on the structural state of forest roads, on four main forest roads in the national forest management offices in Chuncheon and Hongcheon for trafficability. The speeds for the curved and straight sections were 7.6 km/h and 8.7 km/h, respectively, which were less than the designed speed (20 km/h). Thus, it would be necessary to improve the forest road's structure to fulfill minimum running speed. No significant difference was observed in the running speed by the longitudinal gradient up to 13%, while it was increased at more than 100 m by the distance in the straight section. By the facility's location in the curved section, the running speed was 6.2%-9.3% lower in a ridge than a valley. The running speed was lowest at the internal angles of <90° and at the curved radius of <15 m, respectively. When this radius was less than 15 m, the substandard sections for widening amounts were more than 50%; thus, sufficient widening was not achieved.

• Journal of the Korean Association of Geographic Information Studies
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• v.24 no.3
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• pp.41-57
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• 2021

This study evaluated the application of water quality management measures using the SWAT model and the effectiveness of the measures using the load duration curve targeting the Seohwacheon watershed located upstream of Daecheongho. As water quality management measures, artificial wetlands, reduction of neglected livestock, reduction of runoff from greenhouses, restoration of ecological rivers, application of LID technology, and management of point sources were applied. The applied technology evaluated the efficiency of water quality improvement measures by using the target water quality excess rate and the degree of load reduction for each sulfur through the load duration curve. The load duration curve was created by creating a long-term flow duration curve using SWAT and multiplying it by the target water quality. For the target water quality, the value corresponding to the 60th percentile was set as the target water quality using the 10-year data from the Okcheoncheon water quality observation point located in the downstream of Seohwacheon. Through this study, it was possible to confirm the applicability of various water quality measures through the SWAT model, and to examine the applicability of each period according to the sulfur through the load retention curve.

• Journal of Climate Change Research
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• v.4 no.3
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• pp.201-210
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• 2013

In recent years, with the rising interest to reduce greenhouse gas emissions, the demand for using environmentally friendly product with low greenhouse gas emission is increasing in the printing industry as well. In this study, the carbon footprint of environmentally friendly product mineral paper that uses less plastic and wood than normal printing paper materials was analyzed by utilizing the life cycle assessment (LCA) technique. An analysis utilizing the LCA technique was done per the Korea carbon footprint certification guidelines and, for scope of study, it included the premanufacturing stage and manufacturing stage except for the use and disposal stages. As a result of the study, the emission coefficient of the mineral paper was calculated to be $0.81kg\;CO_2eq/kg$ and the emission from electricity usage of the entire greenhouse gas emission was calculated to be 45.85% ($0.37kg\;CO_2eq/kg$). In order to reduce greenhouse gas emission, required are the efforts to reduce the environmental loads by using energies that have relatively lower environmental loads, such as improvement in electricity usage efficiency and renewable energy, by increasing product completion rates during the manufacturing process of mineral paper.

• Journal of Climate Change Research
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• v.1 no.2
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• pp.179-188
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• 2010

To cope with various issues in the aspect of climate change adaptation of UNFCCC, Korea began preparing a Five-year National Climate Change Adaptation Plan in 2010 to be implemented from 2011~2015, for the purposes of securing a concrete system to adapt to climate change. Compared with the policies and measurement tools of developed countries, Korea's climate change adaptation capabilities suffers from a number of limitations including insufficiencies of basic information, human resources for research on climate change, and technology in risk and vulnerability assessment. At the same time, Korea maintains superior information technology systems, and comparatively strong climate change adaptation technologies. Recently, with the establishment of the Korea Adaptation Center for Climate Change as a specialized research organization in climate change adaptation, Korea has upgraded its ability to adapt to climate change and to provide support to other Asian countries which are vulnerable to climate change. In consideration of the close relation between climate change adaptation policy and technology development with the environmental industry, Korea's pursuit of cooperation and technical support for developing countries in the Asia region can be seen as the commencement of a long term investment for the nation's future. International cooperation on climate change adaptation between countries in the region can build a mutually complementary and integrated partnership in business, research, education, and other areas. Furthermore, Korea can also participate in the exploration of common issues as landmark projects that can attract global interest with developing countries.

• Earthquakes and Structures
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• v.15 no.6
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• pp.667-685
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• 2018

In eccentrically braced steel frames (EBFs), the links are fuse members which enter inelastic phase before other structure members and dissipate the seismic energy. Based on the force-based seismic design method, damages and plastic deformations are limited to the links, and the main structure members are required tremendous sizes to ensure elastic with limited or no damage. Force-based seismic design method is very common and is found in most design codes, it is unable to determine the inelastic response of the structure and the damages of the members. Nowadays, methods of seismic design are emphasizing more on performance-based seismic design concept to have a more realistic assessment of the inelastic response of the structure. Links use ordinary steel Q345 (the nominal yielding strength $f_y{\geq}345MPa$) while other members use high strength steel (Q460 $f_y{\geq}460MPa$ or Q690 $f_y{\geq}690MPa$) in eccentrically braced frames with high strength steel combination (HSS-EBFs). The application of high strength steels brings out many advantages, including higher safety ensured by higher strength in elastic state, better economy which results from the smaller member size and structural weight as well as the corresponding welding work, and most importantly, the application of high strength steel in seismic fortification zone, which is helpful to popularize the extensive use of high strength steel. In order to comparison seismic behavior between HSS-EBFs and ordinary EBFs, on the basis of experimental study, four structures with 5, 10, 15 and 20 stories were designed by PBSD method for HSS-EBFs and ordinary EBFs. Nonlinear static and dynamic analysis is applied to all designs. The loading capacity, lateral stiffness, ductility and story drifts and failure mode under rare earthquake of the designs are compared. Analyses results indicated that HSS-EBFs have similar loading capacity with ordinary EBFs while the lateral stiffness and ductility of HSS-EBFs is lower than that of EBFs. HSS-EBFs and ordinary EBFs designed by PBSD method have the similar failure mode and story drift distribution under rare earthquake, the steel weight of HSS-EBFs is 10%-15% lower than ordinary EBFs resulting in good economic efficiency.

• Journal of Wetlands Research
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• v.21 no.2
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• pp.181-190
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• 2019

Recently, Low impact development techniques, a form of nature-based solutions (NBS), were seen cost-efficient alternatives that can be utilized as alternatives for conventional stormwater management practices. This study evaluated the effectiveness of an infiltration trench (IT) and a small constructed wetland (SCW) in treating urban stormwater runoff. Long-term monitoring data were observed to assess the seasonal performance and cite the advantages and disadvantages of utilizing the facilities. Analyses revealed that the IT has reduced performance during the summer season due to higher runoff volumes that exceeded the facility's storage volume capacity and caused the facility to overflow. On the other hand, the pollutant removal efficiency of the SCW was impacted by the winter season as a result of dormant biological activities. Sediment data also indicated that fine and medium sand particles mostly constituted the trapped sediments in the pretreatment and media zones. Sediments in SCW exhibited a lower COD and TN load due to the phytoremediation and microbiological degradation capabilities of the system. This study presented brief comparison LID facilities equipped with pre-treatment zones. The identified factors that can potentially affect the performance of the systems were also beneficial in establishing metrics on the utilization of similar types of nature-based stormwater management practices.

• Economic and Environmental Geology
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• v.54 no.1
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• pp.69-76
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• 2021

This study is to identify the mineralogical properties of caprock samples from drilling cores of the Pohang basin, which is the research area for the demonstration-scale CO2 storage project in Korea. The interaction of water-rock-gas that can occur due to CO2 injection was identified using geochemical modeling. Results of mineralogical studies, together with petrographic data of caprock and data on the physicochemical parameters of pore water were used for geochemical modeling. Modelling was carried out using the The Geochemist's Workbench 14.0.1 geochemical simulator. Two steps of modeling enabled prediction of immediate changes in the caprocks impacted by the first stage of CO2 injection and the assessment of long-term effects of sequestration. Results of minerlaogical analysis showed that the caprock samples are mainly composed of quartz, K-feldspar, plagioclase and a small amount of pyrite, calcite, kaolinite and montmollonite. After the injection of carbon dioxide, the porosity of the caprock increased due to the dissolution of calcite, and dawsonite and chalcedony were precipitated as a result of the dissolution of albite and k-feldspar. In the second step after the injection was completed, the precipitation of dawsonite and chalcedony occurred as a result of dissolution of calcite and albite, and the pH was increased due to this reaction. Results of these studies are expected to be used as data to quantitatively evaluate the efficiency of mineral trapping capture in long-term storage of carbon dioxide.

• Journal of Korean Society of Forest Science
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• v.100 no.3
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• pp.315-326
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• 2011

In recent years, domestic and international interests focus on climate change, and importance of forest as carbon sink have been also increased. Particularly REDD+ mechanism expanded from REDD (Reduced Emissions from Deforestation and Degradation) is expected to perform a new mechanism for reducing greenhouse gas in post 2012. To conduct this mechanism, countries which try to get a carbon credit have to certify effectiveness of their activities by MRV (Measuring, Reporting and Verification) system. This study analyzed the approaches for detecting land cover change and estimating carbon stock by remote sensing technology which is considered as the effective method to develop MRV system. The most appropriate remote sensing for detection of land cover change is optical medium resolution sensors and satellite SAR (Synthetic Aperture Radar) according to cost efficiency and uncertainty assessment. In case of estimating carbon stock, integration of low uncertainty techniques, airborne LiDAR (Light Detection and Ranging), SAR, and cost efficient techniques, optical medium resolution sensors and satellite SAR, could be more appropriate. However, due to absence of certificate authority, guideline, and standard of uncertainty, we should pay continuously our attention on international information flow and establish appropriate methods. Moreover, to apply monitoring system to developing countries, close collaboration and monitoring method reflected characteristics of each countries should be considered.