• Korean Journal of Remote Sensing
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• v.39 no.6_1
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• pp.1517-1522
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• 2023

This study evaluates the impact of Moderate Resolution Imaging Spectroradiometer (MODIS) aerosol optical depth (AOD) expected error (EE) on the accuracy of surface reflectance (SR) derived from the KOMPSAT-3A satellite, utilizing the Second Simulation of the Satellite Signal in the Solar Spectrum Vector radiative transfer model. By considering a range of ground-based AOD and the resultant MODIS AOD EE, the research identifies significant influences on SR accuracy, particularly under high solar zenith angles(SZA) and shorter wavelengths. The study's simulations reveal that SR errors increase with shorter wavelengths and higher SZAs, highlighting the necessity for further research to improve atmospheric correction algorithms by incorporating wavelength and SZA considerations. Additionally, the study provides foundational data for better understanding the use of AOD data from other satellites in atmospheric correction processes and contributes to advancing atmospheric correction technologies.

• Journal of the Korean GEO-environmental Society
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• v.24 no.12
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• pp.53-60
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• 2023

Recently, along with the improvement of high-speed rail and road design speed, the proportion of tunnel construction work is increasing proportionally. In particular, the construction of long tunnels is rapidly increasing due to the mountainous terrain of our country. In this way, due to the trend of tunnels becoming longer, it is difficult to design and construct tunnels by avoiding fault zones. In the case of tunnel construction in mountainous areas, ground investigation is often difficult even during design due to the topographical conditions, making precise ground investigation difficult, and as a result, the upper part of the tunnel is damaged during tunnel construction. When fault zones, which are vulnerable to weathering, exist, the stability of the tunnel during excavation is directly affected by the fault zone distribution, strength characteristics, and groundwater distribution range. In particular, when a fault zone is distributed in the upper part of a tunnel, damage such as tunnel collapse and excessive displacement may occur, and in order to prevent this in advance, countermeasures must be established through analysis of similar cases. Therefore, in this study, when a large-scale fault zone exists in the upper part of a tunnel, the relationship and characteristics of damage to the tunnel structure were analyzed.

• Explosives and Blasting
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• v.41 no.3
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• pp.38-61
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• 2023

An Excavation Damaged Zone(EDZ) caused by blasting impact changes rock properties, in situ stress distribution, etc., and its effects are noticeable at around a radioactive waste repository located at deep underground. In particular, the increase in permeability due to the formation of cracks may significantly increase the amount of groundwater inflow and the possibility of radioactive nuclide outflow. In this study, FLAC2D and FLAC3D were used to analyze the mechanical and thermal behaviors for three categories: a)No EDZ, b)Uniform EDZ, and c)Random EDZ. It was found that the tunnel displacement in the Random EDZ case was 423% higher than that in the No EDZ case and was 16% higher than that in the Uniform EDZ case. Tunnel inflow in the Random EDZ was also 17.3% and 10.8% higher than that in the No EDZ and the Uniform EDZ case, respectively. The permeability around the tunnel was increased by up to 10 times in the corner of the tunnel wall and roof due to the stress redistribution after excavation. From the computer simulation, it was found that the permeability around the tunnel wall was partially increased but the overall tunnel inflow was decreased with increase of stress ratio. Mechanical analysis using FLAC 3D showed similar results. Slight difference between 2D and 3D could be explained with the development of plastic zone during the advance of tunnel excavation in 3D.

• The Journal of the Convergence on Culture Technology
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• v.10 no.5
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• pp.331-339
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• 2024

This study seeks to expand the jewelry market and overall development of the industry by understanding the fashion jewelry market and researching marketing strategies based on changes in market consumption. Looking at recent changes in the jewelry market, the number of new consumers (fashion jewelry buyers) has increased since 2014, leading to a recovery in purchases and strong sales. However, the decline in costs is prolonged, the focus on purchasing low-priced products is increasing, and there is a growing trend of purchasing products other than rings. Items are becoming more diverse, including bracelets and necklaces, and the popularity of imported products and brands is intensifying. Ultimately, the penetration of fashion jewelry and the growth of imported brands are expected to continue for a long time. The fashion jewelry market is a market that appears to have ample potential to grow into a larger market, filling the structural limitations of the jewelry market and providing consumer satisfaction in line with recent consumption trends. If so, We need to think about how to grow and develop this market, and We need to view it as a jewelry market in a broad sense, and it is a market that can serve as a bridgehead for the precious metal jewelry market to expand into the accessory market in the future. Therefore, it is necessary to create a jewelry market by utilizing the advantages of fashion jewelry, such as diversity of materials and expressions, price competitiveness, wide distribution channels and consumer accessibility, reflection of trends, and consumer awareness.

• Journal of Korean Society of Forest Science
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• v.9 no.1
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• pp.1-44
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• 1969

The important results which have been obtained in the investigation can be recapitulated as follows. 1. As demostrated by the experimental results and analyses concerning their effects in the on-ground type mushroom house, the constructions in relation to the side wall and ceiling of the experimental houses showed a sufficient heat insulation on effect to protect insides of the houses from outside climatic conditions. 2. As the effect on the solar type experimental mushroom house which was constructed in a half basement has been shown by the experimental results and analyses, it has been proved to be effective for making use of solar heat. However there were found two problems to be improved for putting solar houses to practical use in the farm mushroom growing: (1) the construction of the roof and ceiling should be the same as for the on-ground type house, and (2) the solar heat generating system should be reconstructed properly. A trial solar heat generating system is shown in Fig. 40. 3. Among several ventilation systems which have been studied in the experiments, the underground earthen pipe and ceiling ventilation, and vertical side wall and ceiling ventilation systems have been proved to be most effective for natural ventilation. 4. The experimental results have shown that ventilation systems such as the vertical side wall and underground ventilation systems are suitable to put to practical use as natural ventilation systems for farm mushroom houses. These ventilation systems can remarkably improve the temperature of fresh air which is introduced into the house by heat transfers within the ventilation passages, so as to approach to the desired temperature of the house without any cooling or heating operation. For example, if it is assuming that x is the outside temperature and y is the amount of temperature adjustment made by the influence of the ventilation system, the relationships that exist between x and y can be expressed by the following regression lines. Underground iron pipe ventilation system ${\cdots}{\cdots}$ y=0.9x-12.8 Underground earthen pipe ventilation system ${\cdots}{\cdots}$y=0.96x-15.11 Vertical side wall ventilation system${\cdots}{\cdots}$ y=0.94x-17.57 5. The experimental results have shown that the relationships existing between the admitted and expelled air and the $Co_2$ concentration can be described with experimental regression lines or an exponent equation as follows: 1) If it is assumed that x is an air speed cm/sec. and y is an expelled air speed in cm/sec. in a natural ventilation system, since the y is a function of the x, the relationships that exist between x and y can be expressed by the regression lines shown below: 2) If it is assumed that x is an admitted volume of air in $m^3/hr$ and y is an expelled volume of air in $m^3/hr$ in a natural ventilation system, since the y is a function of the x, the relationships that exist between x and y can be expressed by the regression lines shown below. 3) If it is assumed that the expelled air speed in cm/sec and replacement air speed in cm/sec. at the bed surface in a natural ventilation system are shown as x and y, respectively, since the y is a function of the x, the relationships that exist between x and y can be expressed by the following regression line: G.E. (100%)- C.V. (50%) ventilation system${\cdots}$ y=0.54X+0.84 4) If it is assumed that the replacement air speed in cm/sec. at the bed surface is shown as x, and $CO_2$ concentration which is expressed by multiplying 1000 times the actual value of $CO_2$ % is shown as y, in a natural ventilation system, since the y is a function of the x the relationships that exist between x and y can be expressed by the following regression line: G.E. (100%)- C.V. (50%) ventilation system${\cdots}{\cdots}$ y=114.53-6.42x 5) If it is assumed that the expelled volume of air is shown as x and the $CO_2$ concentration which is expressed by multiplying 1000 times the actual of $CO_2$ % is shown as y in a natural ventilation system, since the y is a function of of the x, the relationships that exist between x and y can be expressed by the following exponent equation: G.E. (100%)-C.V. (50%) ventilation system${\cdots}{\cdots}$ $$y=127.18{\times}1.0093^{-X}$$ 6. The experimental results have shown that the ratios of the crass sectional area of the G.E. and C.V. vent to the total cubic capacity of the house, required for providing an adequate amount of air in a natural ventilation system, can be estimated as follows: G.E. (admitting vent of the underground ventilation)${\cdots}{\cdots}$ 0.30-0.5% (controllable) C.V. (expelling vent of the ceiling ventilation)${\cdots}{\cdots}$ 0.8-1.0% (controllable) 7. Among several heating devices which were studied in the experiments, the hot-water boilor which was modified to be fitted both as hot-water toiler and as a pressureless steam-water was found most suitable for farm mushroom growing.

• Clinical and Experimental Pediatrics
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• v.52 no.11
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• pp.1273-1278
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• 2009

Purpose:Congenital muscular torticollis (CMT), a common musculoskeletal disorder in infants, is characterized by the rotation and flexion deformity of the neck caused by sternocleidomastoid muscle shortening. We investigated the clinical courses and perinatal risk factors of CMT. Methods:Less than 6-month-old patients (98; M:F = 60:38) diagnosed with CMT between February 2007 and August 2008 were classified into 2 clinical subgroups, namely, SMT (sternocleidomastoid tumor) and POST (postural torticollis). All the patients were physically and neurologically examined prospectively and their cervical X-rays and ultrasonographies were obtained. Their medical histories about perinatal problems were recorded. Of the 98 patients, 45 with normal range of motion were taught passive physical exercises and 43 were referred to the Department of Rehabilitation for undergoing manual stretching therapy. Results:The mean age at initial assessment was 2.2 months (SMT: $1.4{\pm}1.0$, POST: $2.7{\pm}1.6$). SMT presented earlier than POST. All ophthalmologic examinations and cervical X-rays were normal. SMT was associated with higher incidence of caput succedaneum and cephalhematoma. POST was highly associated with plagiocephaly. Mean duration of rehabilitative physical therapy was 3.7 months (SMT: $4.6{\pm}2.5$, POST: $2.6{\pm}1.9$). POST resolved earlier than SMT. Of the 88 patients with follow-up, 87 had total resolution and only 1 had residual torticollis. Conclusion:All the patients received early treatment with passive stretching exercises. CMT was associated with perinatal problems and had various risk factors such as obstetrical problems.

• Journal of Korean Society of Environmental Engineers
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• v.33 no.6
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• pp.413-419
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• 2011

Nanoscale zero-valent iron (NZVI) particles were tested as remediation media for groundwater contaminated by organic pollutants (e.g., TCE, trichloroethylene). The contaminated groundwater contained anions ($NO_3^-$, $Cl^-$, $SO_4^{2-}$, and $HCO_3^-$) and natural organic matter (NOM). Treatability of commercial NZVI particles (NANOFER 25, Nanoiron, Czech) was tested by using a synthetic groundwater and the field groundwater samples. More than 95% of 1.8 mM TCE was removed within 20 hours with a NZVI dosage of 25 g/L ($k=0.15hr^{-1}$). Repetitive degradation experiments revealed that the removal capacity of NANOFER 25 was 0.19 mmole TCE/g NZVI. TCE degradation reactions were not substantially affected by the presence of each anion with concentrations as high as 100 times the average field concentrations. However, when the four anions ($NO_3^-$, $Cl^-$, $SO_4^{2-}$, $HCO_3^-$) were present simultaneously. the degradation reactivity and removal capacity were decreased by 60% ($k=0.069hr^{-1}$) and 10%, respectively. The k value of TCE degradation in the presence of NZVI (25 g/L) with dissovled organic carbon of 2.5 mg/L was also decreased by 84% ($k=0.025hr^{-1}$). In the experiments with the field groundwater, more than 90% of $1.8{\mu}M$ TCE, which is the concentration of TCE at the source zone, was removed within 10 hours with a NANOFER 25 dosage of 25 g/L. The results imply that the contaminated groundwater can effectively be treated by NANOFER 25 with more information on the hydrogeology of the site.

• Korean Journal of Agricultural and Forest Meteorology
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• v.20 no.1
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• pp.5-17
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• 2018

The standardized eddy covariance flux data processing in KoFlux has been updated, and its database has been amended accordingly. KoFlux data users have not been informed properly regarding these changes and the likely impacts on their analyses. In this paper, we have documented how the current structure of data processing in KoFlux has been established through the changes and improvements to ensure transparency, reliability and usability of the KoFlux database. Due to increasing diversity and complexity of flux site instrumentation and organization, we have re-implemented the previously ignored or simplified procedures in data processing (e.g., frequency response correction, stationarity test), and added new methods for $CH_4$ flux gap-filling and $CO_2$ flux correction and partitioning. To evaluate the effects of the changes, we processed the data measured at a flat and homogeneous paddy field (i.e., HPK) and a deciduous forest in complex and heterogeneous topography (i.e., GDK), and quantified the differences. Based on the results from our overall assessment, it is confirmed that (1) the frequency response correction (HPK: 11~18% of biases for annually integrated values, GDK: 6~10%) and the stationarity test (HPK: 4~19% of biases for annually integrated values, GDK: 9~23%) are important for quality control and (2) the minimization of the missing data and the choice of the appropriate driver (rather than the choice of the gap-filling method) are important to reduce the uncertainty in gap-filled fluxes. These results suggest the future directions for the data processing technology development to ensure the continuity of the long-term KoFlux database.

• Journal of Dairy Science and Biotechnology
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• v.33 no.3
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• pp.179-196
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• 2015

Because of our aging population, there is increasing concern about the impact of dementia and age-related cognitive decline. Intense research efforts on effective dietary interventions for the prevention or amelioration of dementia and age-related cognitive decline have indicated that dairy products affect physiological health and potentially healthy brain function during aging. Milk is a rich source of proteins and peptides with nutritional and immunotropic activities. The preparation of biologically active proteins and peptides generally requires enzymatic degradation, chemical modification, or the addition of specific co-factors. Milk-derived preparations are widely available in the food industry in the form of hygiene products and infant formulas. However, milk-derived products could also be applied as preventive or therapeutic measures for a wide-range of pathological conditions not only in neonates and infants but also in adults, including the elderly. Because they have no adverse side effects, milk-derived proteins and peptides could be used as a supplementary treatment for dementia and age-related cognitive decline.

• Journal of Food Hygiene and Safety
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• v.23 no.2
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• pp.163-168
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• 2008

This study investigated the anti-oxidative and anti-cancer activities by extracting of Yacon by fraction with organic solvents. The content of total phenol was the highest by 45.53% in ethyl acetate fraction and the results of electron donating abilities were 65.20% ($100\;{\mu}g/ml$), 91.81% ($500\;{\mu}g/ml$) and 95.06% ($1000\;{\mu}g/ml$) and those of nitrite scavenging abilities were 11.71% ($100\;{\mu}g/ml$), 36.81% ($500\;{\mu}g/ml$), 59.70% ($1000\;{\mu}g/ml$) in ethyl acetate fraction, which were higher concentration than the control group. Xanthine oxidase inhibitory activities were 23.74% ($100\;{\mu}g/ml$) and 43.41% ($500\;{\mu}g/ml$) in low concentration, which showed higher activities than the control group. After measuring the growth inhibitory activities for cancer cells, it has been found that hexane fraction had the highest growth inhibitory activities by 23.75% ($10\;{\mu}g/ml$), 34.67% ($50\;{\mu}g/ml$), 54.21% ($100\;{\mu}g/ml$) for SNU-1. Meanwhile, hexane fraction demonstrated high growth inhibitory activities by 41.38% ($10\;{\mu}g/ml$), 50.53% ($50\;{\mu}g/ml$), 60.91% ($100\;{\mu}g/ml$) and butanol fraction had 17.05% ($10\;{\mu}g/ml$), 43.87% ($50\;{\mu}g/ml$), 62.99% ($100\;{\mu}g/ml$) for HeLa. Therefore, it has been believed that there were peculiar properties of anti-oxidative and anti-cancer activities depending on each fraction. Furthermore, it has been expected that further studies on the development of functional food and concrete components depending on the components of each fraction to be conducted.