• Journal of Sericultural and Entomological Science
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• v.50 no.2
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• pp.53-62
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• 2012

Silkworm larvae often suffer from viral infections causing heavy losses to the economy of silk industry. Insects exhibit both humoral and cellular immune responses that are effective against various pathohens like bacteria, fungi, protozoa, etc., but no insect immune responses is effective against viral infection. To obtain genes related to insect antiviral immunity from Bombyx mori, the cDNA library was constructed from B. mori nucleopolyhedrovirus (BmNPV)-infected B. mori. From the cDNA library, we selected 411 differentially expressed clones, and the 5' ends of the inserts were sequenced to generate ESTs. In this work, 135 unigenes were generated after the assembly of 411 differentially expressed clones ESTs. Of these 135 unigenes, we selected 109 antiviral response-related candidates except 26 clones that high similarity with genes derived from BmNPV. Among 109 unigenes, a total of 80% had significant matches to genes from other organisms in the database, wheres 20% of the unigenes had not matched in the database. Functional groups of these sequences with matches in database were constructed according to their putative biological function. Three largest categories were control of cellular oraganization (52%), metabolism (20%), and protein fate (10%). The genetic information reported in this study will provide more information about antiviral-related genes in silkworms.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.7
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• pp.310-316
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• 2019

In automotive application, customers are demanding high efficiency and various functions for convenience. The demand for these automotive applications is steadily increasing. In this study, it has been studied the analysis of heat flow to improve the PCB(printed circuit board) heating performance of WPC (wireless power charger) recently developed for convenience. The charging performance of the wireless charger has been reduced due to power dissipation and thermal resistance of PCB. Therefore, it has been proposed optimal PCB design, layout and position of electronic parts through the simulation of heat flow analysis and PCB design was analyzed and decided at each design stage. Then, the experimental test is performed to verify the consistency of the analysis results under actual environmental conditions. In this paper, The PCB modeling and heat flow simulation in transient response were performed using HyperLynx Thermal and FloTHERM. In addition, the measurement was performed using infrared thermal imaging camera and used to verify the analysis results. In the final comparison, the error between analysis and experiment was found to be less than 10 % and the heating performance of PCB was also improved.

• Science of Emotion and Sensibility
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• v.24 no.2
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• pp.49-56
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• 2021

In this study, we investigated the necessary mechanical properties of conductive multifilament yarns for fabricating the electrodes of biosignal measurement pressure and stretch textile sensors using embroidery. When electrodes and circuits for smart wearable products are produced through the embroidery process using conductive multifilament yarns, unnecessary material loss is minimized, and complex electrode shapes or circuit designs can be produced without additional processes using a computer embroidering machine. However, because ordinary missionary threads cannot overcome the stress in the embroidery process and yarn cutting occurs, herein, we analyzed the S-S curve, thickness, and twist structure, which are three types of silver-coated multifilament yarns, and measured the stress in the thread of the embroidery simultaneously. Thus, the required mechanical properties of the yarns in the embroidery process were analyzed. In the actual sample production, cutting occurred in silver-coated multifilament rather than silver-coated polyamide/polyester, which showed the lowest S-S curve. In the embroidery process, the twist was unwound through repetitive vertical movement. Further, we fabricated a piezoresistive pressure/tension sensor to measure gauge factor, which is an index for measuring biological signals. We confirmed that the sensor can be applied to the fabrication of embroidery electrodes, which is an important process in the mass production of smart wearable products.

• Journal of Korea Water Resources Association
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• v.54 no.3
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• pp.181-190
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• 2021

In this study, a large-scale levee breach experiment from lateral overflow was conducted to verify the effect of the new reinforcement method applied to the levee's surface. The new method could prevent levee failure and minimize damage caused by overflow in rivers. The levee was designed at the height of 2.5 m, a length of 12 m, and a slope of 1:2. A new material mixed with biopolymer powder, water, weathered granite, and loess in an appropriate ratio was sprayed on the levee body's surface at a thickness of about 5 cm, and vegetation recruitment was also monitored. At the Andong River Experiment Center, a flow (4 ㎥/s) was introduced from the upstream of the A3 channel to induce the lateral overflow. The change of lateral overflow was measured using an acoustic doppler current profiler in the upstream and downstream. Additionally, cameras and drones were used to analyze the process of the levee breach. Also, a new method using 3D point cloud for calculating the surface loss rate of the levee over time was suggested to evaluate the performance of the levee reinforcement method. It was compared to existing method based on image analysis and the result was reasonable. The proposed 3D point cloud methodology could be a solution for evaluating the performance of levee reinforcement methods.

• Journal of the Korea institute for structural maintenance and inspection
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• v.26 no.1
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• pp.49-57
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• 2022

In order to efficiently analysis the stability of a slope, measuring the shear strength of soil is needed. The Standard Penetration Test (SPT) is not appropriate for a slope inspection due to cost and weights. One of the ways to effectively measure the N-value is the Dynamic Cone Penetration Test (DCPT). This study was performed to develop a minimized multi-function sensors that can easily estimate CPT values and Volumetric Water Content. N value with multi-fuction sensor DCPT showed -2.5 ~ +3.9% error compared with the SPT N value (reference value) in the field tests. Also, the developed multi-fuction sensor system was tested the correlation between the CPT test and the portable tester with indoor test. The test result showed 0.85 R2 value in soil, 0.83 in weathered soil, and 0.98 in mixed soil. As a result of the field test, the multi-function sensor shows the excellent field applicability of the proposed sensor system. After further research, it is expected that the portable multi-function sensor will be useful for general slope inspection.

• Korean Journal of Environmental Biology
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• v.40 no.3
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• pp.239-246
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• 2022

Lactuca scariola L. is one of ecosystem-disturbance plants that grow everywhere such as roadsides, grasslands, railroads, banks, and fields. L. scariola usually occurs in autumn. It overwinters in rosette form. It flowers and produces seeds in early summer of the next year. Seeds of L. scariola can germinate immediately without dormancy when the temperature is over 20℃. Due to endogenous bacteria in seeds of L. scariola, it has a strong drought tolerance. Thus, it can grow well on roadsides. L. scariola should be controlled as it can result in 60-80% of soybean yield loss at densities above 50 plants m^-2. It is advisable to remove L. scariola as it competes with native plants by acting as a pioneer to other ecosystem-disturbance plants. Among various control methods, chemical control is the most effective method that is widely used. Soil treatment with herbicides such as oxyfluorfen EC and pendimethalin EC can inhibit the development of L. scariola. Foliar treatment herbicides glyphosate and glufosinateammonium are widely used. L. scariola is resistant to 2,4-D, dicamba, and MCPA among foliar treatment herbicides. Thus, it is recommended to apply herbicides with different modes of action.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.2D
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• pp.243-248
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• 2008

Moisture damage of asphalt pavements can usually occur because of the loss of adhesion and cohesion between the asphalt binder and aggregate in the asphalt mixture due to presence of water. And this is one of the causes that is effect on the main distress of asphalt pavement. The objective of this study is to find out moisture damage characteristics of asphalt pavement. Effects of this study changes of the material properties and resistance characteristics of moisture damage on the asphalt mixtures under various temperatures and repeated immersion using indirect tensile test and modify Lottman test were evaluated during this study. The asphalt mixtures were produced using straight asphalt binder, SBS modified asphalt binder and aggregates. The material properties (resilient modulus, indirect tensile strength, failure energy and $DCSE_f$) of the asphalt mixtures were generally decreased with increasing to moisture damage caused by the number of repeated immersion. The decrease ratios of material properties by repeated immersion on SBS modified asphalt mixtures were lower than those of straight asphalt mixtures at all three test temperatures. As a conclusion, current criterion for evaluation moisture damage of asphalt mixtures is difficult for using distinction standard because of the limited evaluation criterion with one time immersion and single material property. Based on this research, to evaluate long term moisture damage on asphalt mixtures, material property tests of various kinds with repeated immersion test are considered.

• Journal of the Korean Electrochemical Society
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• v.27 no.1
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• pp.40-46
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• 2024

Among the electrode manufacturing processes for lithium-ion batteries, the drying process is crucial for production speed and process cost. Particularly, as the loading level of the electrode increases to enhance the energy density of the battery, optimizing process conditions for electrode drying becomes more critical. In this study, we compared the drying time and electrochemical performance of the positive electrode prepared at different drying temperatures. LiNi_0.6Co_0.2Mn_0.2O₂ (NCM622) was used as the active material and manufactured under various drying temperature conditions ranging from 120 ℃ to 210 ℃ at loading levels of 2.5 and 4.5 mAh cm^-2. The physical and electrochemical properties of the electrodes were compared. As the loading level of the electrode increases, the drying time of the electrode also increases, but this time can be reduced by increasing the drying temperature. The drying temperature used in manufacturing the NCM622 positive electrode does not significantly affect the electrochemical performance but drying above 210 ℃ resulted in an increase in the volume resistivity of the electrode and a decrease in electrochemical performance. Accordingly, in the manufacture of high-loading electrodes, the drying temperature was increased to 190 ℃ to shorten the electrode manufacturing time without a loss of performance.

• The Korean Journal of Mycology
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• v.29 no.1
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• pp.15-21
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• 2001

This study was conducted to investigate the immunomodulatory activities of proteoglycan extracted from cultured mycelia of Ganoderma lucidum IY009. The proteoglycan contained two polymer peaks, one was the higher MW peak of 2,000 kD and the other was low peaks of 12kD. To understand the part of strong pharmaceutical activity between two peak, the proteoglycan was separated by ultrafiltration and column chromatography and then examined the various pharmaceutical effects. High molecular weight fraction possesing high content of ${\beta}-linked$ glucan was exhibited high antitumor activity, against sarcoma 180 bearing ICR mouse. And also, anticomplementary activity was highly observed in high molecule fraction than low it fraction. When the raw 264.7 and murine peritoneal macrophage treated with low fraction, high fraction and other stimuli. The activities inducing tumor necrosis factor of the high factions were $2.2{\sim}2.5$ times stronger than that of low fraction.

• Journal of Korean Society of Forest Science
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• v.106 no.4
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• pp.397-407
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• 2017

This research aims to analyze and compare the drought resistance of 7 species of landscape trees commonly grown in Korea. The 7 species are: Camellia japonica, Rhaphiolepis indica, Quercus glauca, Machilus thunbergii, Daphniphyllum macropodum, Dendropanax morbifera and Cinnamomum camphora. In order to analyze their drought resistance, the samples were left without irrigation for 30 days (05/09/2016 ~ 05/10/2016), during which period their respective drought resistor, relative water content, electrolyte elution figures and proline content were measured. As the non-irrigation proceeded, C. camphora was the first to wither, followed by D. morbifera, then D. macropodum, then M. thunbergii, then Q. glauca, then R. indica then finally C. japonica. Of the 7 species, Q. glauca, C. japonica and R. indica can be considered highly drought resistant, since they survived for longer than 3 weeks without irrigation. Relative water content (RWC) plummeted dramatically after the first 15 days of non-irrigation. Whereas RWC readings of C. camphora, D. morbifera, D. macropodum and M. tunbergii dropped by 40% or more, the other 4 species reported a relatively low rate of decrease at 20% or lower. The Camellia japonica, the R. indica and Q. glauca, which were the species with relatively high drought resistance, showed low proline content and electrolyte elution figures, whereas those of C. camphora, D. macropodum, D. morbifera and M. tunbergii were higher. Analysis through the nonlinear regression analysis logistic model showed that non-irrigation proved fatal for the 7 sample species in a range of 22.7 to 37.6 days. The C. japonica, R. indica, Q. glauca and M. tunbergii demonstrated a high drought resistance of 30 days or longer, whereas C. camphora, D. morbifera and D. macropodum had a low resistance of 25 days or less to drought from lack of water. In conclusion, out of the 7 species of broad-leaved evergreen trees tested, C. japonica, R. indica and Q. glauca seem to be suitable for use as landscape trees, owing to their high drought resistance.