• Korean journal of applied entomology
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• v.32 no.2
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• pp.176-183
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• 1993

These sutdies were conducted to investigate the joint toxic action of mixtures of several acaricides including amitraz, bifenthrin, propargite, fenbutatin dxide and bxide dicofol to the field-collected strian of Tetranychus urticae. The synergistic action of acaricidal mixtures was greatly varied with the kind of acaricide combinations and their mixture ratios. The combinations of amitraz with each of the tested acaricides were synergized at the given mixture ratios. The higher synergistic action in the each combination was observed at 2 : 8 ratio of amitraz and bifenthrin, 8 : 2 ratio of amitraz and fenbutatin oxide, 4 : 6 ratio of amitraz and propargite and 6 : 4 ratio of amitraz and dicofol.

• Korean journal of applied entomology
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• v.37 no.2
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• pp.207-212
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• 1998

Tea field-collected populations of the tea red spider mite (Tetranychus kazawai Kishida) from five different locations in the southern region of Korea were assessed for resistance to seven acaricides using leaf spray method. There were considerable differences in susceptibility depending on the tested acaricides and the location from which the population was collected. The populations showing high resistance ratio of more than 20 with respect to certain acaricide were as follows: the Sungjun and Cheju populations to azocyclotin, tebufenpyrad, fenpyroximate, pyridaben, propargite, and fenpropathrin; the Haenam population to propargite and fenpyroximate; the Bosung population to propargite; the Youngam population to pyridaben. Therefore, the use of other alternative acaricides against the Sungjun and Cheju populations is needed. However, careful selection of the appropriate acaricide against the Haenam, Bosung and Youngam populations of the tea red spider mite might be maintained in effective control.

• KEPCO Journal on Electric Power and Energy
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• v.5 no.4
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• pp.311-321
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• 2019

With Korean Government's Renewable energy 3020 plan and 8th Basic plan for long-term power supply, renewable energy industries in Korea are active and catching attention from many relevant industry's relations. Especially with Interconnection guarantee policy established in Oct, 2016, DERs interconnection delay due to lack of allowable distribution hosting capacity is happening and reduction of reinforcement cost for distribution system where 70 % of DERs in South Korea are installed became one of important issues of KEPCO. Therefore, KEPCO needed to extract reasonable solutions to increase feasible hosting capacity of distribution feeders in order to reduce reinforcement cost under the condition of no matter in distribution system operation. This paper proposes feasible hosting capacity of distribution feeders that can be adopted and the status of DER installation in distribution system, PV output data, minimum load in distribution feeders as well as capacity of distribution lines have been investigated and analyzed in proof of the proposal.

• Korean journal of applied entomology
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• v.17 no.2 s.35
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• pp.75-80
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• 1978

The study was conducted to determine the inherited properties of the MEB resistance to natural population of the small brown plant-hopper(Laodelphax striatelluss). The plant-hoppers were collected from the natural population of Naju area where the highest insecticide resistance of MEF to the green rice leaf hopper (Nephotettix cincticeps) have been examined in 1976. And Naju collections were crossed to the susceptible Lab stock to examine the MEP resistance in the $F_1,\;BC_1F_1\;and\;F_2$ and $F_2$ populations. Ail the data were analyzed by the probit method. There was a difference in MEP resistance between Naju collection and susceptible Lab stock, showing $LD_{50}$ value of the former was 0.0029ug/insect compared to 0.0008ug/insect for the later. The $LD_{50}$ values and dosage-mortality lines of the $F_1$ and $BC_1F_1$ tended to close their resistant parent. and it was considered that the character of the MEP resistance in the Naju collection of the small brown plant hopper was controlled by the genetic traits. However, $LD_{50}$ value and dosasage-mortality lines of the $F_2$ populations were intermediate to their parents, it would be conclusive that the trait will be governed by a interaction of the genes or factors rather than the single genic control.

• Weed & Turfgrass Science
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• v.6 no.2
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• pp.136-150
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• 2017

Zoysiagrass mite, Aceria zoysiae is one of the main turfgrass pests causing significant damage on zoysiagrass. In this study we investigated damage by zoysiagrass mite for the selection of zoysiagrass mite-resistance turfgrass individual in natural collected turfgrass isolates transplanted in genetic resources conservation area. In the results of investigation of 295 turfgrass isolates collected from Korea, damage level was different depending on turfgrass species and individuals. Zoysia japonica was highly damaged representing 97.6%, followed by hybrid zoysia and Z. sinica with damage percentages of 87.7% and 81.1% respectively. Additionally, 2 individuals of Z. macrostachya were also damaged by zoysiagrass mite. However several individuals were not damaged by zoysiagrass mite in green house and field. Damage by zoysiagrass mite was occurred from May and peak at after July in field. The study highlighted some important resistant turfgrass individuals which can be used in the management of zoysiagrass mite.

• The Korean Journal of Pesticide Science
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• v.2 no.3
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• pp.117-125
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• 1998

Flupyrazofos (O,O-diethyl-O-(1-phenyl-3-trifluoromethyl-5-pyrazoyl)thiophosphoric acid ester) is a new organo-phosphorous insecticide. Flupyrazofos has exhibited excellent activity against diamondback moth (Plutella xylostella, DBM), and it is highly activity against rice armyworm(Pseudaleta separata) and cotton caterpillar(Palpita indicae). Flupyrazofos has then revealed outstanding both rapidity and residual action for DBM, although no systemic actions were observed and no cross-resistances were found to the resistance strains (Op-R, Py-R, IGR-R). Also, susceptibilities of five local strains to flupyrazofos were similar to those of the susceptible strain. These results indicate that flupyrazofos has considerable potential for controlling diamondback moth, rice armyworm and cotton caterpillar in field.

• Proceedings of the KIPE Conference
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• 2020.08a
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• pp.236-238
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• 2020

신재생에너지의 보급 확대와 함께 전 세계적으로 ESS에 대한 수요가 빠르게 증가하는 추세이며 최근 태양광 발전을 기반으로 하는 ESS 제품이 다양하게 출시 되고 있다. 해당 제품들은 가정에서 전기 공사 후 제품이 고정되어 운용된다. 본 논문에서는 야외용 전원 및 UPS기능을 가진 portable ESS에 대해 언급하고 있으며 그중에서도 DC_LINK제어 방식을 논하고 있다. 기존에 사용한 고정 DC LINK 방식의 문제점을 살펴보고 가변 DC LINK에 대한 시뮬레이션 및 1.5kW급 PCB 제작을 통해 실제 성능 및 동작을 검증한다.

• Journal of The Korean Society of Grassland and Forage Science
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• v.22 no.4
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• pp.265-272
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• 2002

Forage breeding laboratory of National Livestock Research Institute, R.D.A. has made interspecific hybrids of Lolium multiflorum $\times$ L. pratensis and intergeneric hybrids of Lolium $\times$ Festuca since 1984, and has collected ecotypes of Italian ryegrass since 1991. Growth characteristics of these hybrids and ecotypes were researched, and then these clone lines were named. Among these clone lines, the several clones that have polen fertility, high cold-tolerance, and similar heading time were used for making synthetics, Naehan 6, 7, 8, 9, with polycrossing method in 1997. Field experiments were carried out to compare the mophological and agronomical characteristics and forage productivity and quality of the synthetics with those of Italian ryegrass varieties, Barmultra and Hwasan 101. in Suwon and Yonchun from 1999 to 2000. Heading time of the synthetics were 22th to 24th May that belong to late-mature types to be similar to that of Barmultra and Hwasan 101 in Suwon. The synthetics were 101 to 106 c3n in plant length, medium or thick in thickness of stem, dark peen in leaf color, broad and long in flag leaf, strong in lodging resistance, and excellent in regrowth. Winter survivals of the synthetics were no different from that of Barmultra or Hwasan 101 in Suwon, but better than that of Barmultra or Hwasan 101 in Yonchun where was -10 to -12$^{\circ}C$ of minimum average air temperature in January or February. Dry matter(DM) yields of the synthetics were similar to DM 8,238kg per ha of Barmultra in Suwon, but in Yonchun, were more 7 to 13% than DM 7,291kg per ha of Barmultra. Forage qualities, IVDMD, ADF, NDF and TDN of the synthetics were lower than those of Hwasan 101, but higher than those of Barmultra.

• Journal of Sericultural and Entomological Science
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• v.48 no.2
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• pp.61-67
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• 2006

We investigated fertilization rate, hatchability rate, pupation rate and cocoon quality etc to selecting good characteristics of the wild silkmoth, Antheraea yamamai using method of indoor-and outdoor-rearing. As results of indoor rearing, the healthiness of A. yamamai was better in light green colour strain than that of dark green colour strain, but cocoon quality was better in dark green colour strain. There was a little effect to selecting major characteristics in grade of A, B and C strain classified with cocoon weight. $F_1$ hybrid was lower in fertilization rate and hatchability rate than parent, but higher in pupation rate and cocoon quality. There was no effect of heterosis in $F_2$ hybrid. In case of outdoor rearing, mortality rate was lower than that of indoor rearing but missing larva was higher. In addition, outdoor rearing is higher that indoor rearing in cocoon weight, cocoon shell weight and cocoon shell rate.

• Korean journal of applied entomology
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• v.53 no.2
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• pp.149-156
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• 2014

The resistance levels of the green peach aphid, Myzus persicae (Sulzer), against 10 insecticides was checked and selected the applicable insecticide resistance markers. We conducted our study in 5 cabbage cultivation regions (Pyeongchang, Hongcheon, Bongwha, Muju, and Jeju) of Korea, over 3 successive years (2009-2011). We selected a multi-resistant (MR) strain from among the 5 field-collected populations. We analyzed esterase over-expression and mutation(s) in the target sites, by using native isoelectric focusing (IEF) and quantitative sequencing (QS). We detected esterase over-expression and StoF mutation in the acetylcholinesterase 1 gene (ace1) in all of the field-collected populations, including the MR strain. We did not detect the LtoF mutation, which is a well-known knockdown resistance (kdr) mutation in the para-type sodium channel gene (para), in the MR strain; however, the value of the MR strain for bifenthrin was 3,461-fold higher than that of the susceptible strain. Our results indicate that insecticide resistance is more effectively evaluated using molecular markers than by conducting a bioassay. The molecular markers StoF in ace1 and MtoL in para can easily be applied in diagnostic methods such as QS or PCR amplification of specific alleles (PASA). These methods may be extended to management of M. persicae resistance in the field.