• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.06a
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• pp.15-15
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• 2010

$Na_2Ti_6O_{13}$ (NT)가 도핑된 $BaTiO_3-(Bi_{0.5}Na_{0.5})TiO_3$ BBNT) PTCR 세라믹스를 변형된 세라믹공정을 이용하여 제조하였다. 제조된 BBNT 세라믹의 미세구조와 PTCR 특성에 미치는 NT의 효과를 조사하였다. $1300^{\circ}C$에서 합성된 BBNT 세라믹은 NT의 도핑량이 증가함에 따라 비정상적으로 성장된 입자의 수가 증가하였다. 뿐만 아니라, NT의 도핑량 증가는 상온비저항을 약간 증가시켰지만 큐리온도 (Tc) 부근의 최대비저항/최소비저항으로 정의되는 PTC 점프 특성을 크게 향상시켰다. 특히, 0.01mol%의 NT 도핑 시 상온비저항은 $425\;\Omega{\cdot}cm$, PTC 점프는 ($2.02{\times}^10^5$) 저항온도계수는 69.8% 및 Tc는 $155^{\circ}C$의 우수한 결과를 나타내었다.

• The Korean Journal of Food And Nutrition
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• v.10 no.4
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• pp.475-479
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• 1997

The effects of amino acids and metabolites in growth media on the biosynthesis of prodigiosin from Serratia marcescens ATCC 25419 were examined. The prodigiosin synthesis was decreased approximately by 50 to 80% by several amino acids and metabolites tested. The prodigiosin synthesis was increased approximately by 20 to 40% by a low concentration of glyoxylate(1 to 3mM) and outstandingly increased by 122% at 5mM concentration under anaerobic condition. However, the prodigiosin synthesis was decreased approximately by 50 to 90% at a high concentration(20 to 30mM) under anaerobic condition. The prodigiosin was not synthesized by pyruvate and $\alpha$-ketobutyrate under aerobic and anaerobic condition, with addition to glyoxylate under aerobic condition, among the range from 0.5 to 30mM, while the cell growth under anaerobic condition was decreased distinctly by a high concentration(20mM above) of glyoxylate. These data suggest that the growth and prodigiosin of S. marcescens is positively regulated by a low concentration of glyoxylate (1-5mM), but repressed by a high concentration of glyoxylate(20mM above) unlike pyruvate and $\alpha$-ketobutyrate.

• Journal of the Korean earth science society
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• v.25 no.6
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• pp.474-483
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• 2004

This paper analyzed the characteristics of daily ozone variations over Kangreung and Wonju. It was found that the diurnal cycle of ozone over Wonju has a primary ozone peak in the afternoon and a minimum around sunrise, which is a typical diurnal ozone cycle observable in the urban area. However, the cycle over Kangreung shows a primary peak in the afternoon and secondary peak around 3 a.m. The amounts of ozone in the secondary peak is occasionally higher than that in the primary peak. This nocturnal ozone peak is frequently observed year-round, and the highest frequency and extent are observed in spring. The possible cause of this nocturnal ozone increase was investigated using meteorological parameters and the HYSPLIT trajectory model. It was found that the nocturnal ozone peak is highly correlated with strong wind speed, which has led to positive temperature anomaly. The trajectory model revealed that when the secondary peak occurred, the air was originated from the west and a sinking motion subsequently followed. These findings suggested that when the westerly wind is strongest in spring, the polluted airs from urban areas are transported to the upper boundary layer over Kangreung area. In the case of strong wind during the night, nocturnal ozone peaks were produced by active vertical mixing between lower boundary and upper boundary layers.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.16 no.6
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• pp.385-391
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• 2023

As the use of electric vehicles has increased to minimize carbon emissions, the analyzing the state and performance of lithium-ion batteries that is instrumental in electric vehicles have been important. Comprehensive analysis using not only the voltage, current and temperature of the battery pack, which can affect the condition and performance of the battery, but also the driving data and charging pattern data of the electric vehicle is required. Therefore, a thorough analysis is imperative, utilizing electric vehicle operation data, charging pattern data, as well as battery pack voltage, current, and temperature data, which collectively influence the condition and performance of the battery. Therefore, collection and preprocessing of battery data collected from electric vehicles, collection and preprocessing of data on driver driving habits in addition to simple battery data, detailed design and modification of artificial intelligence algorithm based on the analyzed influencing factors, and A battery analysis and evaluation model was designed. In this paper, we gathered operational data and battery data from real-time electric buses. These data sets were then utilized to train a Random Forest algorithm. Furthermore, a comprehensive assessment of battery status, operation, and charging patterns was conducted using the explainable Artificial Intelligence (XAI) algorithm. The study identified crucial influencing factors on battery status, including rapid acceleration, rapid deceleration, sudden stops in driving patterns, the number of drives per day in the charging and discharging pattern, daily accumulated Depth of Discharge (DOD), cell voltage differences during discharge, maximum cell temperature, and minimum cell temperature. These factors were confirmed to significantly impact the battery condition. Based on the identified influencing factors, a battery analysis and evaluation model was designed and assessed using the Random Forest algorithm. The results contribute to the understanding of battery health and lay the foundation for effective battery management in electric vehicles.

• Korean Journal of Food Science and Technology
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• v.40 no.1
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• pp.1-7
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• 2008

Quality attributes of welsh onion (Allium fistulosum L.) as affected by harvest timing (November, December 2006 and January 2007) and storage temperature (5, 10 and $20^{\circ}C$) were investigated in terms of respiration rate, weight loss, decay rate, color, hardness, sensory quality. A higher respiration rate was found when welsh onions were harvested later and storage temperature was higher. A smaller weight loss was observed in welsh onions that were harvested in November and stored at temperature of $5^{\circ}C$, demonstrating a 9.35% reduction. In other words, there were a minimum difference of 2.15% and a maximum difference of 9.92% between the weight loss in test samples harvested in November and those of test samples harvested in other months. The decay rate was higher in welsh onions harvested in January. The degree of color was more stable in test samples kept at temperature of $5^{\circ}C$ than those kept at higher temperature (10 and $20^{\circ}C$). There were, however, no significant differences in color changes among test samples harvested at different times of the year. Thus color change is closely associated with temperature. Also, welsh onions were harvested in November and stored at temperature of $5^{\circ}C$ showed a good sensory quality.

• Current Research on Agriculture and Life Sciences
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• v.15
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• pp.33-38
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• 1997

This investigation was attemped to know fruit quality of apple 'Fuji' grown at three different areas of Taegu. Fruits were gathered from hill side area : Kyungsangpookdo yongchongun chongtongmynn synwonri, flat area : Kyungsangpookdo yongchongun synyoungmyun youujeongri and river side area : Kyungsangpookdo yongchongun kewmhoyeub naenhchundong. Results were as follows: 1. In fruit sampling, we made an effort to select the same size of fruit from all areas, However, the size at river side area was about 40g lighter and minimum length was shorter than those of the other areas. On the other hand, maximum and minimum diameter of the fruit at flat and river side areas were longer than hill side area. Accordingly, shape index of the fruit in river side area was flatter than the other areas. This difference may be due to temperture, soil moisture content, etc. In squeeze rate of the fruit, no significant difference was recognized among areas. 2. Though, rate of fructose in total sugar was almost 50% in all areas, sucrose, fructose and sorbitol concentration of hill side area were higher than the other areas. however glucose was reverse amd brix was almost same as total sugar concentration. 3. Rate of malic acid in total acid was almost 98% and citric acid was only 2% in all areas. Malic acid concentration of hill side area was higher than the other areas and titratable acid concentration was almost same as total acid.

• Korean Journal of Food Science and Technology
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• v.18 no.6
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• pp.468-474
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• 1986

The emulsifying properties of soy protein isolate were measured at various conditions, and the relationships between the emulsifying properties and solubility, viscosity, hydrophobicity, protein adsorption, the tension at water-oil interface were investigated. The emulsifying properties are minimum at the isoelectric point(pI), and the effect of pH parallels its effect on protein solubility. The emulsifying activity is increasing up to $50^{\circ}C$ and then is somewhat decreasing above that temperature, while the emulsion stability is continuously decreasing. Except for phosphates, the salts cause the decrease of the emulsifying properties. The hydrophobicity is increasing as the temperature increases and decreasing somewhat as pH gets lower. However, it is increasing substantially at pH below the pI. The maximum protein adsorption at the water-oil interface is 0.78, 0.47, and $0.33mg/m^2$ at pH 2, 7, and 4, respectively. The tension at water-oil interface is 19.76 dyne/cm in the absence of soy protein, whereas it is decreasing to 11.45-18.08 dyne/cm in the presence of the protein.

• Journal of Korean Society of Environmental Engineers
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• v.31 no.10
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• pp.873-882
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• 2009

Sonolysis of TCE (Trichloroethylene) was performed in 584 kHz rectangular reactor. At first, the effect of acoustic power and aqueous temperature which are both important factors to operate ultrasound system on sonolysis of TCE were examined under one side irradiation condition. First degradation rate constants of TCE and chloride yields were increased with increasing acoustic power from 100 to 300 W. And increasing the aqeuous temperature resulted in the increase of first degradation rate constants of TCE and the decrease of chloride yield. Sonolysis of TCE was performed under multi ultrasound irradiation conditions that total acoustic power of 300 W was distributed according to the number of irradiation sides. First degradation rate constants of TCE followed the order 4 sides > 3 sides > 1 side > 2 sides (parallel) > 2 sides (orthogonal). When comparing the experimental results under parallel and orthogonal irradiation conditions of 2 sides with 300 and 450 W, first degradation rate constants of TCE were similar, while production rate constants of hydrogen peroxide were more higher at parallel conditions compared to orthogonal conditions.

• Korean journal of applied entomology
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• v.1
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• pp.20-25
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• 1962

A. The increases moisture contents of grain at R.H $75\%,\; and\; 28^{\circ}C$ 1) The moisture contents of polished rice were $0.4\%,\; 1 \%,\; 3.3\%$ higher than control after 4weeks in which had been infested with 100, 200, 500 individuals of weevil at the beginning. respectively. 2) The greatest moisture contents of polished rice was $16.26\%$ for 500 individual infested grain and the lowest one was $14.86\%$ for the 100 individual weevil infested grain after 4 weeks. 3) The increases in moisture contents of grain were proportionally greater with the size of the weevil population. B. Changes in moisture contents of polished rice at the three levels of cylinder which contain 3kgs of grain and 1000 weevils were infested at the beginning of the experiment. 1) The moisture contents of the grain at all the levels of the cylinder which was not infested with weevil, were consistantly decreased in 12 weeks. 2) The moisture contents of the grain at all the levels of the cylenders which had been infested with 1000 weevils at the beginning of the experiment, were increased except top lovel, that were $15.6\%$ for middle, $41.55\%$ for the bottom levels after 12 weeks. 3) The moisture contents of the grain were greater toward bottom in both weevil infested grain and in control. 4) The moisture content increase might be caused by the respiration of the weevils and deterioration of the grain by microorganisms. 5) There were no tendency to confine the weevils at any definite levels, but as the deterioration of the grain goes on, the weevil moved to top levels of cylinders. 5) The decreases in moisture contents of the grain at the top levels of the cylinders might be caused by diffusion of water to the environment. 7) The differences in temperature at three levels of the cylinder from enviroment were little or negative in control but were greater and positive. and the bottom were higher than top in experimental cylinders. 8) The increases of temperature might be caused by the respiration of the weevil and microorganisms.

• Journal of Korea Water Resources Association
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• v.49 no.6
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• pp.551-563
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• 2016

According to the 4th and 5th assessment of the Intergovernmental Panel on Climate Change (IPCC), global climate has been rapidly changing because of the human activities since Industrial Revolution. The perceived changes were appeared strongly in temperature and concentration of carbon dioxide ($CO_2$). Global average temperature has increased about $0.74^{\circ}C$ over last 100 years (IPCC, 2007) and concentration of $CO_2$ is unprecedented in at least the last 800,000 years (IPCC, 2014). These phenomena influence precipitation, evapotranspiration and soil moisture which have an important role in hydrology, and that is the reason why there is a necessity to study climate change. In this study, Asia region was selected to simulate primary energy index from 1951 to 2100. To predict future climate change effect, Common Land Model (CLM) which is used for various fields across the world was employed. The forcing data was Representative Concentration Pathway (RCP) data which is the newest greenhouse gas emission scenario published in IPCC 5th assessment. Validation of net radiation ($R_n$), sensible heat flux (H), latent heat flux (LE) for historical period was performed with 5 flux tower site-data in the region of AsiaFlux and the monthly trends of simulation results were almost equaled to observation data. The simulation results for 2006-2100 showed almost stable net radiation, slightly decreasing sensible heat flux and quite increasing latent heat flux. Especially the uptrend for RCP 8.5 has been about doubled compared to RCP 4.5 and since late 2060s, variations of net radiation and sensible heat flux would be significantly risen becoming an extreme climate condition. In a follow-up study, a simulation for energy index and hydrological index under the detailed condition will be conducted with various scenario established from this study.