• KSCE Journal of Civil and Environmental Engineering Research
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• v.41 no.6
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• pp.675-686
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• 2021

This study investigated the ground displacement occurring in a slope below a waste-rock dumping site and estimated the likelihood of a disaster due to a landslide. To start with, photogrammetry was conducted by unmanned aerial vehicles (UAVs) to investigate the size and extent of the ground displacement. From April 2019 to July 2020, the average error rate of the five UAV surveys was 0.011-0.034 m, and an elevation change of 2.97 m occurred due to the movement of the soil layer. Only some areas of the slope showedelevation change, and this was believed to be due to thegroundwater generated during rainfall rather than the effect of the waste-rock load at the top. Sensitivity analysis for LS-RAPID simulation was performed, and the simulation results were compared and analyzed by applying a digital elevation model (DEM) and a digital surface model (DSM)as terrain data with 10 m, 5 m, and 4 m grids. When data with high spatial resolution were used, the extent of the sedimentation of landslide material tended to be excessively expanded in the DEM. In contrast, in the result of applying a DSM, which reflects the topography in detail, the diffusion range was not significantly affected even when the spatial resolution was changed, and the sedimentation behavior according to the river shape could be accurately expressed. As a result, it was concluded that applying a DSM rather than a DEM does not significantly expand the sedimentation range, and results that reflect the site situation well can be obtained.

• Journal of Applied Biological Chemistry
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• v.65 no.2
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• pp.113-120
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• 2022

We examined the anti-inflammatory properties of Nostoc commune HCW0811 in lipopolysaccharide-stimulated RAW264.7 macrophage cells. The anti-inflammatory activity of HCW0811 on viability of treated cells was assessed by measuring the level of expression of NO, prostaglandin E₂ and pro-inflammatory cytokines, namely interleukin-1β, interleukin-6, and tumor necrosis factor-α in HCW0811 treated RAW 264.7 macrophages. HCW0811 was non-toxic to cells and inhibited the production of cytokines in a concentration-dependent manner. In addition its treatment suppressed the production of pro-inflammatory cytokines in a dose-dependent manner, and concomitantly decreased the protein expressions of inducible NO synthase and cyclooxygenase-2. Moreover, the levels of the phosphorylation of mitogen-activated protein kinase family proteins such as extracellular signal-regulated kinase, c-Jun N-terminal kinase, p38, and nuclear factor kappa B were reduced by HCW0811. These findings suggest that the HCW0811 collected from Daejeon National Cemetery have anti-inflammatory effects, and demonstrated its efficacy in cell-based in vitro assays.

• Korean Journal of Plant Resources
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• v.35 no.2
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• pp.183-191
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• 2022

Ginseng (Panax ginseng C.A. Meyer) is a perennial plant and propagates by seeds, and those need after-ripening for germination. To be ready for climate change and to ensure a stable seed supply, the technique for storing seeds in short-term and long-term in large quantities is required. In this study, dehisced ginseng seeds from two locations, batch #1 and batch #2, were stored at -3.5℃ with different moisture content, and after 3, 15, and 27 months of storage, the percentage of radicle emergence and shoot emergence were measured. After 3 months, radicle emergence and shoot emergence were normal only when the seed moisture content was more than 35%, and overall, germination was higher in batch #2 than in batch #1. After 15 months, the partially dehydrated seeds, with a moisture content between 45 to 54%, showed the highest germination rates, and most of the undried seeds were spoiled and failed to germinate. Seeds with moisture content lower than 25% had poor germination, too. The partially dehydrated seeds also succeeded in germination and growth in the soil after 15 months of storage, but deteriorated after one more 1 year, too. In summary, ginseng seeds look like have temperate recalcitrant seed characteristics, and partial dehydration allows extension of seed longevity.

• Korean Journal of Remote Sensing
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• v.38 no.6_1
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• pp.1101-1107
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• 2022

The leaf temperature is principally regulated by the opening and closing of stomata that is sensitive to various kinds of plant physiological stress. Thus, the analysis of thermal imagery, one of remote sensing technique, will be useful to detect crop physiological condition on smart farm system and phenomics platform. However, there are few case studies using a thermal imaging camera on the agricultural application. In this study, three cases are presented: the effect of lime fertilizer on the rice, the different physiological properties of soybean under shading condition, and the screening of soybean breeds for salinity tolerance characteristic. The leaf temperature measured by thermal imaging camera on the three cases was used effectively to the physiological change and characteristics. However, the thermal imagery analysis requires considering the accuracy of measured temperature and the weather conditions that affects to the leaf temperature.

• Korean Journal of Environment and Ecology
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• v.36 no.4
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• pp.402-412
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• 2022

This study investigated each forest's stand characteristics and the NVOCs emission characteristics for Quercus acuta, Castanopsis sieboldii, Dendropanax trifidus, Camellia Japonica which are major warm temperate evergreen broad-leaved species, and Pinus thunbergii. Data were collected from May 2019 to January 2020. The seasonal temperature and humidity of each research site indicated the typical climatic characteristics of Korea, which are hot and humid in summer and cold and dry in winter. Also, the atmospheric pressure was generally high in winter and higher in autumn and winter than in spring and summer. Overall, the total volume of NVOCs (Natural Volatile Organic Compounds) from the five research sites was the highest in the summer. The concentration of TNVOCs was relatively high in the Dendropanax trifidus forest in spring and winter, the Castanopsis sieboldii forest in the autumn, and the Quercus acuta forest in the summer. According to the results of this study, it was confirmed that the concentrations of NVOCs emission of warm temperate evergreen broad-leaved species such as Quercus acuta, Castanopsis sieboldii, Dendropanax trifidus and Camellia Japonica were not lower but rather higher than Pinus thunbergii. The correlation was positive (+) between NVOCs emission and temperature (r=0.590, P=0.000) or humidity (r=0.655, P=0.000), whereas it was negative (-) between NVOCs emission and atmospheric pressure (r=-0.384, P=0.000) or wind speed (r=-0.263, P=0.018). Among the micrometeological factors, humidity (β=0.507, P=0.000) was found to have the greatest effect on NVOC emission, followed by temperature, atmospheric pressure, and wind speed.

• Journal of the Korean GEO-environmental Society
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• v.22 no.6
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• pp.5-15
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• 2021

One of the construction methods applied as a pier foundation type is a single type cast-in-place pile. In applying a pile bent system as a foundation type, the main concern in designing can be said to secure the lateral bearing capacity of pile structure in system. In addition, to increase the rigidity of the pile structure, a method of increasing the lateral bearing capacity by reinforcing the pile structure with a casing has been used. However, although the reinforcing effect and appropriate reinforcing length of casing may vary depending on the soil conditions, there is insufficient studies on this, and for this reason, the entire pile structure in a pile bent system is reinforced with a casing, in the field. In addition, if the length of the entire pile is reinforced with a casing, it may lead to delays in construction and increase in construction costs. That is, in order to more effectively reinforce the pile structure with a casing, it is necessary to study the lateral bearing characteristics of the reinforced pile structure in system. And it should be determined the appropriate reinforcing length of the casing from the evaluated bearing characteristics. Therefore, in this study, the lateral bearing characteristics of piles applied with the reinforcing length of casing for each condition were evaluated through a numerical analysis. And, based on the analysis results, the appropriate reinforcing length of casing was proposed. As a result of the study, it was found that in order to effectively increase the lateral bearing capacity of pile structure, the reinforcing length of casing should be applied twice the influence range of the bending behavior of the pile, 1/β.

• The Korean Journal of Archival Studies
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• no.69
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• pp.129-152
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• 2021

With the enactment and enforcement of the 「Public Records and Archives Act」, the Tottori Prefectural Archives newly enacted the "Records Management Ordinance" through a comprehensive review of the previous archive function. In accordance with this ordinance, which came into effect in April 2012, Tottori Prefecture expanded the records management institutions (Public Security Committee and Police Headquarters, etc.) A series of archive systems were improved, such as the expansion and reinforcement of the authority to appraisal and select. In addition, the Tottori Prefectural Archives went further and implemented the "Ordinance on the Preservation of Historical Documents, etc." from April 2017. Through this, the municipalities unit basic local government's record management support work was set as a unique function of the local archive, and a linkage and cooperation system was established for the preservation of private records of the prefecture area as well as the basic local area together with cultural heritage institutions such as museums and libraries. As a reference case that continuously guarantees the performance of various activities based on the mission and vision of the local archives in Korea that aim for 'autonomy of records' on the poor archival culture soil, it is worth paying attention to the case of continuous record management reform of the Tottori Prefectural Archives through the enactment of the original role and function of the archive.

• Journal of the Korean Geosynthetics Society
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• v.21 no.4
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• pp.69-78
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• 2022

Geotextile tubes are widely used to prevent erosion in coastal areas and to replace the backfill for shore slopes in the reclamation of land using dredged soil. In this study, The triaxial confining pressures were chosen as 10kPa, 50kPa, or 100kPa for the specimens reinforced with geotextile considering the condition in the site. The strain behavior under various compressive stresses was then identified. At strains 0% to 7%, the stress-strain behavior was the same due to the effect of initial strain hardening, in which the force was exerted according to the relaxation of the geotextile regardless of the confining pressure (≤100kPa). At strains of 7% or more, the specimen with the small confining pressure had smaller deformation under load, which increases the tensile resistance provided by the reinforcing geotextile. Brittle fracture was then observed due to strain softening and the deviator stress abruptly decreased. This is different from the phenomenon in which the shear strength increases as the confining pressure increases in general triaxial compression tests. In the geoxtile-confined tests, geotextiles are primarily subjected to tensile displacement. Thereafter, the modulus of elasticity increases rapidly, which exhibits the elastic behavior of the geotextile.

• Journal of the Korean Geotechnical Society
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• v.37 no.11
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• pp.37-49
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• 2021

Micropiles are widely used in construction field to enhance bearing capacity and reduce settlement of existing foundation. It has various benefits such as low construction expense, simple installation process, and small construction equipment. Recently, new microple equipped with the base expansion structure at the end has been developed to improve the foundation bearing capacity. The improvement of load capacity can be conceptually achieved by expanding the base expansion structure when a load is applied to the micropile. However, the expansion mechanism of the base expansion structure and the improvement of load capacity of the micropile were not yet experimentally validated. Therefore, in this study, a series of centrifuge model tests was performed to evaluate the effect of the base expansion structure on the improvement of load capacity. Two types of soil, sand and weathered rock, were prepared and the loading tests were performed using the real micropile with the base expansion structure. During the tests, the earth pressures surrounding the base expansion structure were monitored. As a result, when a load of 30 kN was applied to the micropile, the increase in the ratio of the horizontal to vertical pressure increment (∆σ_h/∆σ_𝜈) ranged from 0.4 to 0.58 in sand and ∆σ_h/∆σ_𝜈 = 0.19 in weathered rock, respectively. Therefore, it can be concluded that the increase in the horizontal earth pressure adjacent to the base expansion structure will improve the bearing capacity of the micropile.

• Research in Plant Disease
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• v.28 no.2
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• pp.61-68
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• 2022

Powdery mildew and two-spotted spider mite are detrimental to strawberry plants and are controlled with traditional pesticides. To accommodate consumer demand, eco-friendly methods of pest control are required. Strawberries were cultivated (in soil and in a hydroponic system) for two years, and ultraviolet B (UV-B) irradiation was used as an alternative pest control during the harvesting season. Three varieties were grown (Seolhyang, Kingsberry, and Durihyang), and four UV-B lamp/mulch (black, green, and light reflection sheet [LRS]) combinations were used during harvesting: UV-B+black or green mulch, UV-B+black or green+LRS, no UV-B+black or green, and no UV-B+black or green+LRS. In all varieties, powdery mildew was 65% more controlled when UV-B irradiation was used. The adult two-spotted spider mite density was lowest in the UV-B lamp+black or green+LRS treatments. Therefore, UV-B irradiation during the strawberry harvesting season could effectively control powdery mildew and two-spotted spider mite with little side effect on the plants.