• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.19 no.11
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• pp.1061-1066
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• 2006

This paper presents the electrical characteristics with manufacturing process and performance evaluation of high performance zinc oxide varistors. ZnO varistors were fabricated with typical ceramic production methods with different thickness and the structural and electrical characteristics of ZnO varistors were investigated. All varistors exhibited high density, which was in the range of $5.41{\sim}5.49g/cm^3$. In the electrical properties, the reference voltage increased in the range of $4.410{\sim}5.250kV$ with increasing their thickness and the residual voltage exhibited the same trends as the reference voltage. In the long duration current impulse withstand test, E-2 and F-1 samples failed at the two and four shots of impulse current, respectively, but E-1 and F-2 samples survived 18 shots during the test. Before and after this test, the variation ratio of residual voltage of E-1 and F-2 samples were -0.34 % and 0.05 %, respectively, which were in the acceptance range of 5 %. According to the results of tests, it is thought that if the fabrication process such as insulating coating, sintering condition, and soldering method is improved, these ZnO varistors would be possible to apply to the station class arresters in the near future.

• Korean Journal of Food Science and Technology
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• v.34 no.4
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• pp.617-624
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• 2002

Health drinks were prepared with freeze dried powder of 60% ethanol extract (60% EFDP), 60% ethanol extract after hydrolysis with amyloglucosidase (60% AEFDP) and 80% ethanol extract (80% EFDP) from roasted safflower seed. Quality characteristics and antioxidative properties were investigated. Yield of freeze dried powders were ranged in $4.67%{\sim}5.62%$. Brix, pH and titratable acidity of safflower drinks were ranged in $11.4{\sim}14.2%$, $2.83{\sim}3.34$ and $0.09{\sim}0.91%$, respectively. Content of total phenolic compounds was much more in 80% EFDP (117 mg/g) and safflower drink-I (SD-I, 440 ppm) than others. Content of total flavonoid was observed in higher level in 60% EFDP (49 mg/g) and safflower drink-V (SD-V, 138 ppm) than others. Antioxidant compounds such as N-[2-(5-hydroxy-1H-indol-3-yl)ethyl]ferulamide(serotonin-I) and N-[2-(5-hydroxy-1H-indol-3yl)ethyl]-p-coumaramide(serotonin-II) exhibited higher contents of 21.09 ppm, 33.56 ppm in 60% EFDP and of 3.83 ppm, 5.81 ppm in safflower drink-II (SD-II) than others. Content of acacetin was much more in 80% EFDP (13.53 ppm) and safflower drink-IV (SD-IV, 1.14 ppm) than others. From the DPPH test to measure antioxidant activity, it was shown that 80% EFDP and SD-I have stronger scavenging activities of 94.58% and 94.88%, respectively, while BHA standard solution does 93.88%. Among drinks, SD-II was revealed to have highest level on overall acceptance, color and flavor through sensory evaluation. These results induced that safflower seed can be used as natural antioxidant and functional food material.

• The Plant Pathology Journal
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• v.18 no.2
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• pp.68-73
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• 2002

The influence of fungicidal spray was assessed on powdery mildew epidemics caused by Erysiphe polygoni D.C. and on yield-attributing characters of mungbean [Vigna radiata (L.) Wilczek]. Mildew attack adversely affected the yield-attributing characters of mungbean and exhibited negative significant correlation with pod length (-0.57), pods/plant (-0.74), pod weight (-0.68), 100 seeds weight (-0.69), 100 seeds swell weight (-0.59), and seed germination (-0.71). These characters had direct or indirect effects on grain yield, which was also adversely affected due to mildew attack (-0.89). Powdery mildew was significantly retarded due to the single spray of carbendazim (0.05%) at 30-day-old crop, where the apparent rate of infection (r) was minimum at 0.0095/ unit/day and with low (11.44%) powdery mildew intensity. Other fungicides like tridemorph (0.075%) and penconazole (0.05%) were equally effective against the mildew disease where the disease intensity was less than 20% and the values of r were 0.0134 and 0.039/unit/day respectively, as compared with the control at 0.267/unit/day. Fungicide spray influenced the yield-attributing characters besides controlling the disease. Such effects were more pronounced in carbendazim (0.05%)-treated plots due to its phytotonic nature where pod length (7.59cm), pods/plant (29.75), pod weight (8.16 g), 100 grain weight (3.94 g), and swell weight of 100 seed (9.49 g) were maximum resulting to the highest yield (480 kg/ha) as compared with that of control (224 kg/ha). Spray of carbendazim also improved seed germination (74.5%). Spray of other fungicides like carbendazim with copper oxychloride in 1:1 ratio, tridemorph (0.075%), and penconazole (0.05%) was equally effective against powdery mildew of mungbean. These fungicides also exhibited positive effects on yield-attributing characters of the crop and finally increased yield. These systemic fungicides were more effective in controlling powdery mildew disease of V. radiata in the rainy season compared with wettable sulphur.

• International Journal of Computer Science & Network Security
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• v.21 no.1
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• pp.152-161
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• 2021

The paper focuses on Device-to-device (D2D) Architectures evaluation frameworks. D2D communication and discovery can improve spectrum usage efficiency and optimize the tradeoffs between throughput and energy consumption. The target operation modes involve both indirect communication between two nodes via a base station or the direct communication among proximal nodes, enabling use cases that can support communications out of cellular coverage, as well as low end-end delay requirements. The paper will present the architectural evolution of D2D networks within 3GPP standardization and will highlight key network functionalities and signaling protocols. It will also identify key analytical and simulation models that can be used to assess the performance and energy efficiency of resource allocation strategies, and it will present a suitable cross-layer integrated framework.

• Ocean and Polar Research
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• v.43 no.3
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• pp.99-111
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• 2021

Occurrence of epiphytic dinoflagellates (EPDs) in coastal waters off Jeju was first reported in 2011 based on 45 substrate samples from 24 macroalgal species. When re-analyzing, the extreme heterogeneous distribution of whole and genus-specific EPDs was reconfirmed across the sampling stations and substrate macroalgal species, as well as even across substrate samples of the same species. Abundance maximum of an EPD genus (cells g-wwt^-1) at a fixed surface-to-volume ratio (SA/V ratio) of the macroalgal species increased as the SA/V ratio increased up to 500 (cm² cm^-3). However, the abundance maximum of Ostreopsis further increased even in the MG2 (morphological group 2) macroalgae with the SA/V ratios over 500. The number of substrate macroalgal species on the plane of the MG and sampling station was more or less evenly scattered than the average EPD abundance, which was primarily driven by Gambierdiscus and Ostreopsis. Of the total EPD abundance of the five stations, 90.6% were represented by the two most common and abundant genera, Gambierdiscus and Ostreopsis, each accounting for 41.6% and 49.0%. Spatially, 95.9% of the total EPD abundance was found in St. 4 and St. 5, of which St. 4 with higher water temperature had more Ostreopsis spp. (31.8%), and St. 5 with higher salinity had more Gambierdiscus spp. (27.3%). Thus, the environmental transition to favorable T-S condition to MG2, the thin filamentous macroalgal group with very high SA/V ratios, is thus likely to support further success in EPD genera led by Ostreopsis in the coastal waters of Jeju.

• Advances in nano research
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• v.3 no.2
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• pp.97-109
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• 2015

Citrate ion is a commonly used reductant in metal colloid synthesis, undergoes strong surface interaction with silver nanocrystallites. The slow crystal growth observed as a result of the interaction between the silver surface and the citrate ion makes this reduction process unique compared to other chemical and radiolytic synthetic methods. The antimicrobial effects of silver (Ag) ion or salts are well known, but the effects of citrate coated Ag nanoparticles (CAgNPs) are scant. Herein, we have isolated biofilm causative bacteria and fungi from drinking water PVC pipe lines. Stable CAgNPs were prepared and the formation of CAgNPs was confirmed by UV-visible spectroscopic analysis and recorded the localized surface plasmon resonance of CAgNPs at 430 nm. Fourier transform infrared spectroscopic analysis revealed C=O and O-H bending vibrations due to organic capping of silver responsible for the reduction and stabilization of the CAgNPs. X-ray diffraction micrograph indicated the face centered cubic structure of the formed CAgNPs, and morphological studies including size (average size 50 nm) were carried out using transmission electron microscopy. The hydrodynamic diameter (60.7 nm) and zeta potential (-27.6 mV) were measured using the dynamic light scattering technique. The antimicrobial activity of CAgNPs was evaluated (in vitro) against the isolated fungi, Gram-negative and Gram-positive bacteria using disc diffusion method and results revealed that CAgNPs with 170ppm concentration are having significant antimicrobial effects against an array of microbes tested.

• Korean Journal of Soil Science and Fertilizer
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• v.31 no.1
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• pp.67-71
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• 1998

This study was carried out to granulate artificial zeolite powder that remove ammonium nitrogen and phosphorous simultaneously in wastewater treatment. Optimum water content was required for 30 percent volume to granulate artificial zeolite with 1.7mm diameter and 1~2cm length using granulator. Portland cement could remove much $NH_4{^+}$ and $PO_4{^{3-}}$ from the wastewater than other binding materials. Mixed 33, 25. 20. 16 percent of portland cement to artificial zeolite powder(v/v), cation exchange capacity of the granulars were 66.5, 81.4, 126.8, $151.2cmol^+kg^{-1}$ and hardness of that were 176.1, 24.4, 4.1, $0.4kg\;cm^{-2}$, respectively. Content of portland cement in the granular were related with removal of $PO_4{^{3-}}$ positively and that of $NH_4{^+}$ negatively. Shaked 1g of the granulars that made of portland cement 33 percent with 40ml synthetic wastewater containing $NH_4{^+}$ $1545mgl^{-1}$ and $PO_4{^{3-}}$ $417mgl^{-1}$, 99.4 percent of $NH_4{^+}$ and 90.3 percent of $PO_4{^{3-}}$ were removed simultaneously after 48 hours shaking. The longer shaking, the more $NH_4{^+}$ and $PO_4{^{3-}}$were removed. The artificial zeolite granular had both micropore and macropore that could be useful in the wastewater purification.

• The Korean Journal of Pesticide Science
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• v.4 no.1
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• pp.59-63
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• 2000

Isolates of Phytophthora infestans obtained from several locations of Kangwon area in 1998 and 1999 were examined on mating types and sensitivity to metalaxyl. Both A1 and A2 mating type isolates were isolated in 1998 and 1999. The majority of the P. infestans isolates were A1 mating type. About 64.3% of the isolates collected in 1998 and 99.1% in 1999 were determined as A1 mating type. Sensitivity of the P. infestans to metalaxyl was examined by measuring mycelial growth on V8 juice agar amended with $10{\mu}g/mL$ matalaxyl. About 44.6% of the isolates examined in 1988 were resistant to metalaxyl, 55.4% of the isolates were intermediate resistant, but sensitive isolate was not isolated. However, 10.5% of the isolates examined in 1999 were sensitive, 88.6% of the isolates were intermediate resistant, and 0.9% of the isolates were resistant to metalaxyl. This studies indicate that A1 mating type is displacing A2 mating type and metalaxyl sensitivity of the P. infestans isolates of Kangwon area is increasing. This result is quite different from trends of early in 1990s.

• Journal of Korea Society of Digital Industry and Information Management
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• v.14 no.1
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• pp.15-25
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• 2018

ISO/IEC 15118 is a standard for communications and services for electric vehicle charging infrastructure. Although this standard deals only with data communication between an electric vehicle and a charge station, communication with the outside is essential for establishing an authentication system for vehicle certification and V2G service for electric power transmission. In this study, it was designed to verify the information of electric car charging infrastructure in electric power system through communication link between ISO/IEC 15118 electric vehicle model and IEC 61850 standard MMS protocol. This is demonstrated in the field so that the electric vehicle communication data is linked with the micro grid management system. This could be used as an element technology in other distributed power sources as well as electric cars in the future.

• Asian-Australasian Journal of Animal Sciences
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• v.1 no.2
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• pp.107-114
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• 1988

Six steers of each breed type, Hereford ($H{\times}H$), Brahman ($B{\times}B$) and Brahman $\times$ Hereford ($B{\times}H$) were ranked on liveweight and allocated to three treatments, basal hay diet (Basal), Basal plus 1 kg/head/day of cottonseed meal (Basal + CSM) and Basal plus 1 kg/head/day of formaldehyde-treated sunflower meal, $Norpro^{(R)}$ (Basal + NPO). The hay was made from a pasture based predominantly on carpet grass (Axonopus affinus) growing in subtropical New South Wales, and had an estimated organic matter digestibility of 52% and a nitrogen (N) content of 7.8 g/kg dry matter (DM). The steers were accustomed to the Basal diet over 15 days and supplements offered over 42 days. Intake of the basal hay diet by steers was not increased by supplementation. When intakes were adjusted for differences between breed types in liveweight the $B{\times}H$ steers ate 25% (P<0.01) more hay than $H{\times}H$ steers (6.3 V 5.0 kg/head/d) and $B{\times}B$ steers ate 8% less hay than $H{\times}H$ steers. Supplementation significantly (P<0.01) increased liveweight gain during the experiment, being ($g/head/d\;{\pm}\;s.e.d.$) 290, 770 and $795{\pm}118$ respectively for Basal, Basal + NPO and Basal + CSM. There was no difference between supplements in the liveweight gain of steers nor between steers of different genotypes. However, there was a significant interaction (P<0.01) between breeds and treatments such that $B{\times}B$ steers gained most on the basal diet but least of the breed types when supplemented. The estimated non-degradeable fraction of N in the protein meals was 58.5 and 44.5%, respectively for NPO and CSM. Both meals increased (P<0.01) plasma urea N and rumen ammonia N concentrations.