• Korean journal of applied entomology
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• v.45 no.2 s.143
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• pp.161-167
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• 2006

The citrus leafminer (CLM), Phyllocnistis citrella Stainton, is an oligophagous pest of Rutaceae family, especially Citrus spp. occurring in most worldwide citrus-growing areas. This study was conducted to evaluate a sex pheromone chemical of CLM, (Z,Z)-7,11-hexadecadienal (7Z,11Z-16:Al) in monitoring CLM by trap types, the diel activity and the influence of some weather factors on trap catch. CLM was well attracted on a trap baited 7Z,11Z-16:Al 1mg. Sticky wing trap was more effective than bucket trap. Most caught CLM were attracted at 2$\sim$6 a.m. regardless of season, and activity time of CLM was affected by sunrise time as well as sunset time. The trap catch of CLM was more influenced by wind velocity than temperature for activity time of CLM. The number of caught CLM was fallen at below 13$^{\circ}C$, but there was little effect for trap catch at over that temperature. The average wind velocity at over 2.0 m/sec made the number of caught CLM drop down. The precipitation did not affect the number of caught CLM when the average wind velocity was lower than at 2.0 m/sec.

• Journal of the Society of Disaster Information
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• v.12 no.1
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• pp.98-104
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• 2016

This study clarifies the simulation on freezing of remaining water in the Z-trap set up in the PVC sewage bay to control malodor. It made use of commercial FEM LAB program(ver. 3.2) well known as a solution of the problems arising in the flow of various fluid, heat transfer and mass transfer. Simulation results under the temperature $-20^{\circ}C$ outwards show that the water in the Z-trap set up in the sewage bay to control malodor freeze in the 60cm under the ground level after 14 days in the wet ground, and after 17 days in the regular ground. On the other hand, if the soil is dry even after the 42 days does not go down below freezing. Therefore, the water in the Z-trap was confirmed that it does not freeze.

• Korean journal of applied entomology
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• v.46 no.3
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• pp.349-356
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• 2007

Three active components (Z8-12:Ac, E8-12:Ac, and Z8-12:OH) are known in sex pheromone of the oriental fruit moth, Grapholita molesta, and have been commercially available to apply for population monitoring and mating disruption. However, there have been variation among commercial products in pheromone composition and amount impregnated in each pheromone releaser. This study was performed to optimize factors influencing on pheromone monitoring of G. molesta by analyzing pheromone composition/amount, effective period of releaser, and trap type/placement in apple trees. High purity of Z8-12:Ac component was effective to attract males, in which 96% or more of cis acetate isomer component appeared to be optimal composition. Pheromone amounts ($0.01-1\;{\mu}g$) impregnated in each rubber dispenser did not give significant effect on monitoring during 90 days from June to August. "Delta" trap was much more efficient than "cone" trap to collect males. Trap installation was another factor, in which placing traps at canopy level was much efficient than at trunk or ground levels. Pheromone trap monitoring with these optimal factors indicated three to four adult peaks from June to September in addition to high overwintering population from April to May in pesticide-applied orchards in Andong, Korea.

• Journal of IKEEE
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• v.26 no.1
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• pp.50-55
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• 2022

SiC is a power semiconductor with a wide bandgap, high insulation failure strength, and thermal conductivity, but many deep-level defects. Defects that appear in SiC can be divided into two categories, defects that appear in physical properties and interface traps that appear at interfaces. In this paper, Z_1/2 trap concentration 0 ~ 9×10¹⁴ cm^-3 reported at room temperature (300 K) is applied to SiC substrates and epi layer to investigate turn-on characteristics. As the trap concentration increased, the current density, Shockley-read-Hall (SRH), and Auger recombination decreased, and Ron increased by about 550% from 0.004 to 0.022 mohm.

• Korean journal of applied entomology
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• v.56 no.2
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• pp.165-169
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• 2017

Seasonal occurrence of persimmon bark borer moth, Euzophera batangensis, and attractiveness of its sex pheromone gland components and trap types were studied at sweet (non-astringent) persimmon orchards of two southern provinces of Gyeongsangnam-do and Jeollanam-do, Korea, from 2014 to 2016. E. batangensis occurred three times a year. Occurrences of the moths of the over-wintered, the $1^{st}$ and the $2^{nd}$ generations were early April to late May, early June to late July, and early August to mid October, respectively. The (Z9,E12)-tetradeca-9,12-dien-1-ol (Z9,E12-14OH) was more attractive than (Z)-tetradec-9-en-1-ol (Z9-14OH). The Z9,E12-14OH was equally attractive to the 9:1 binary mixture of Z9,E12-14OH and Z9-14OH to the male moths. The three trap types of funnel, white and red delta traps had no effect on the attractiveness of the components.

• The Korean Journal of Pesticide Science
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• v.17 no.3
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• pp.200-205
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• 2013

Mating disruption experiments were evaluated and compared in several pheromone traps and sex pheromone composition ratios at commercial chestnut garden for developing alternative control method of D. punctiferalis. The highest attractive was shown in Delta traps at the effective sex pheromone ratio of 75:25 (E10-16:A1:Z10-16:A1). Comparisons of domestic and imported pheromone constituents were not significant difference in 90:10 (E10-16:A1:Z10-16:A1). But, there was significant difference in sex pheromone ratio of 75:25. D. punctiferalis was caught the highest number in Gongju area for attractive test using pheromone trap. Attractive effects with dose of pheromone were showed the highest at 2.5 mg/lure and 1 mg/lure in Gongju area and Cheongyang area respectively. However, there was no significant difference among pheromone dose in Buyeo area. These data could be useful for eco-friendly managing of D. punctiferalis in the chestnut farm.

• Korean journal of applied entomology
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• v.61 no.1
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• pp.77-83
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• 2022

This study was conducted to determine the optimal composition of sex attractant for monitoring adults of the tobacco cutworm, Spodoptera litura, in Korea. Lures of different compositions from the two sex pheromone components the female, (Z,E)-9,11-tetradecadienyl acetate (Z9E11-14:Ac) and (Z,E)-9,12-tetradecadienyl acetate (Z9E12-14:Ac), were compared for male attraction using synthetic chemicals, rubber septa, and funnel traps in soybean and peanut fields. After sequential tests were conducted using three sets of the two components different ranges from 5:5 to 10:1, from 9:1 to 99:1, and from 9:1 to 39:1, the 19:1 ratio was identified as the most efficient composition. However, S. litura males were barely caught in the trap of the Z9E11-14Ac single component lure. The results show that both the sex attractant compounds are necessary for monitoring adults S. litura males. The higher the pheromone amount in the dispenser in the range from 0.1 to 10 mg, the more males were attracted. Furthermore, the trap height of 1.5 m was optimal for male capture.

• Korean journal of applied entomology
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• v.62 no.3
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• pp.131-137
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• 2023

The striped fruit fly, Zeugodacus scutellata (Diptera: Tephritidae), is one of important pests in Cucurbitaceae plants. The cuelure is currently using with various forms for surveillance to the Z. scutellata male as well as Z. cucurbitae, Z. tau, and Bactrocera tryoni, which are categorized as prohibited-quarantine fruit flies in Korea. This study was conducted to verify the attraction effect of applying the cuelure in different forms in field conditions. In this study, we used cuelure by 3 different forms as solid, liquid, and wax to striped fruit flies using the Steiner trap. The trap was placed in two Jeju and one Gyeongbuk regions and the number of attracted flies by each cuelure form is monitored by every 2 weeks during 2021. Attraction effect on Z. scutellata was significant difference by different cuelure forms in two Jeju regions. Liquid and wax forms of cuelure showed high attraction number to the Z. scutellata male compared with solid form when flies were occurred with high population from July to August in Jeju. However, there was no significant difference on attraction effect at low population in Juju and Gyeongbuk by different forms. Based on field assay, liquid and wax form of cuelure are recommended for surveillance against Z. scutellata male. Furthermore, these results also strongly suggest that the attractant, liquid and wax forms of cuelure, could be effective for surveillance to quarantine fruit flies such as Z. cucurbitae, Z. tau, and B. tryoni in Korea.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.22 no.11
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• pp.949-955
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• 2009

In this study, we investigated the effects of Cr dopant (1.0 at% $Cr_2O_3$ sintered at $1000^{\circ}C$ for 1 h in air) on the bulk trap (i.e. defect) and interface state levels of ZnO using dielectric functions ($Z^*$, $M^*$, $Y^*$, $\varepsilon^*$, and $tan{\delta}$), admittance spectroscopy (AS), and impedance-modulus spectroscopy (IS & MS). For the identification of the bulk trap levels, we examine the zero-biased admittance spectroscopy and dielectric functions as a function of frequency and temperature. Impedance and electric modulus spectroscopy is a powerful technique to characterize grain boundaries of electronic ceramic materials as well. As a result, three kinds of bulk defect trap levels were found below the conduction band edge of ZnO in 1.0 at% Cr-doped ZnO (Cr-ZnO) as 0.11 eV, 0.21 eV, and 0.31 eV. The overlapped defect levels ($Zn^{..}_i$ and $V^{\cdot}_0$) in admittance spectra were successfully separated by the combination of dielectric function such as $M^*$, $\varepsilon^*$, and $tan{\delta}$. In Cr-ZnO, the interfacial state level was about 1.17 eV by IS and MS. Also we measured the resistance ($R_{gb}$) and capacitance ($C_{gb}$) of grain boundaries with temperature using impedance-modulus spectroscopy. It have discussed about the stability and homogeneity of grain boundaries using distribution parameter ($\alpha$) simulated with the Z"-logf plots with temperature.

• Journal of the Society of Disaster Information
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• v.15 no.3
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• pp.450-458
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• 2019

Purpose: The purpose of this study is to develop a new sewage bay that has removed its previous problems and verify the excellence of the maintainability of the new sewage bay. Method: The fluid characteristics in the developed sewage bay was analysed with computer simulation tool(COMSOL MultiphysicsTM ver. 3.2 ; COMSOL) and clarified the problems of the existing sewage bay. In addition, the durability of the newly developed sewage bay was verified by the long-term usability testing. Results: As a result of the simulation of a blocked drainage trap, an whirlpool and blockage did not occurred at the flow rate of 0.6m/sec, and we verified that switch device of drain trap was in good condition durably with 6 months long-term usability test. Conclusion: In this study, a newly advanced sewage bay was developed that solved the problems of the existing sewage bay structure. With the fluid simulation and the long-term usability tests, the excellence of the maintenance ability of the newly developed sewage bay was proved.