• 센서학회지
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• 제32권6호
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• pp.455-461
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• 2023

We investigated the electrical characteristics of ZnO nanoparticles (NPs) with air exposure that is a widely used electron transport layer for quantum dot light-emitting diodes (QLEDs). Upon air exposure, we observed changes in the density of states (DOS) of the trap levels of ZnO NPs. In particular, with air exposure, the concentration of deep trap energy levels in ZnO NPs decreased and electron mobility significantly improved. Consequently, the air-exposed ZnO reduced leakage current by approximately one order of magnitude and enhanced the external quantum efficiency at the low driving voltage region of the QLED. In addition, based on the excellent conductivity properties, high-brightness QLEDs could be achieved.

• 한국환경농학회지
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• 제28권4호
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• pp.468-471
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• 2009

This study was conducted to determine the phototactic response of Paratlanticus ussuriensis to different wavelength of light by the use of LEDs and to provide a basic information for developing an improved trap with the longer trapping efficiency to control environment-friendly this katydid. P. ussuriensis were attracted to the single LED light source, especially, blue and white. For the multiple LED light sources, the movement of P. ussuriensis was not significantly different among LED-light bands. Overall, P. ussuriensis had a tendency to move to light source although they were not attracted to a specific wavelength of light. These methods may be used as information for conducting a phototactic response of other insects.

• 한국응용곤충학회지
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• 제31권1호
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• pp.45-49
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• 1992

파밤나방은 기존 살충제에 대한 저항성이 강하기 때문에 전남 진도의 파 집단 재배단지에서 합성 성훼로몬을 이용한 방제의 가능성을 검토하여 다음과 같은 결과를 얻었다. 파를 가해하는 해충중 우점종은 파밤나방과 파굴파리였으며, 두 종은 포장에 따라 경합을 이루어 우점종이 달랐다. 성훼로몬 트랩에 의한 방제효과는 초기에 피해가 많았던 포장은 처리 4주후에 피해엽수가 급격히 감소하고, 중간 정도의 포장은 2주후에는 약간 증가하거나 감소하였지만 4주후에는 같은 경향으로 급격히 감소하였고, 초기피해가 낮은 포장은 계속 낮은 피해가 유지되었으며, 8주후에는 파 60주당 피해엽수가 무처리 포장에서 평균 33.2개의 반면 처리포장에서는 0.2~3개로 조절되었다. 또한 pheromone trap에 의한 웅성충의 유인량도 설치 초기에는 1.8~5.0마리로 적었으나, 2주후부터는 점차 증가하기 시작하여 8주후에는 77.4마리로 초기에 비해 유인량이 28배 가량 많아졌다. 성훼로몬 트랩 유인량과 피해엽수와는 부의 상관관계(r={TEX}$-0.9572^{*}${/TEX})가 인정되었다. 또한 색광별 light trap의 유인량은 30일 동안 적색에 6마리, 백색에 11마리, 청색에는 전혀 유인되지 않은 반면 pheromone trap에는 1,041마리가 유인되었다.

• 한국습지학회지
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• 제14권4호
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• pp.687-698
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• 2012

본 연구는 마산시에서 준설공사 완료 후 준설토 투기장에서 유해곤충의 대량발생을 조사하고, 피해를 예방하기위해서 실시되었다. 모니터링은 텐트트랩, 색상착상트랩, CDC라이트 트랩을 이용하여 실시하였다. 조사결과, 3목 10과 23종 217,073개체의 곤충류가 채집되었다. 텐트트랩을 이용한 월동조사에서 채집된 3종 중 2종(애기똥파리(Leptocera fuscipennis (Haliday))와 극동물가파리(Ephydra japonica Miyagi)는 대량발생 종이었다. 색상점착트랩에서는 16종 중 5종(물가파리금좀벌(Urolepis maritima Walker) (43%), 극동물가파리(19%), Fucellia sp. 1(13%), Philotelma sp. 1(10%), Homalometopus sp. 1(9%))이 전체 개체수의 약 96%를 차지하였다. CDC 라이트트랩에서 우점종은 Homalometopus sp. 1(91%), 도꾸나가조각깔따구(Glyptotendipes tokunagai Sasa) (6%), 애기똥파리(1%)로 전체의 약 98%를 차지했다. 조사시 개체수의 급격한 증가가 관찰되었을 경우에는 유해곤충의 대량발생으로 인한 피해를 막기 위해서, 가열연막과 유충성장억제제 사용을 최소화하면서, 대량발생지역 복토, 유문등 사용, 물빼기작업 등의 환경적인 저감방법을 수행하여 그 결과를 분석하였다.

• 한국전기전자재료학회논문지
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• 제17권6호
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• pp.668-672
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• 2004

Upon Debye's dielectric relaxation theory, we tried simple determination method of trap level in organic EL materials. From dielectric measurements in the 20 Hz - 1 MHz frequency range and in the 150 K - 320K temperature range, the depth of traps in Alq$_3$ filled with remaining electrons was determinated. Comparing to other determination techniques like TSL, or TL, the apparatus all we need is just simple LCR meter, thermometer and cooling method(liquid nitrogen). The mean activation energy is about 0.20 eV. It is in good agreement with previous determinations by other techniques like TSL. This results consolidate the validity of Burrow's transport mechanism model. Further intensified experiment with UV light on the dielectric absorption(Photodipolair effect) was nevertheless disturbed by the photoconductivity component.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 추계학술대회 논문집 Vol.17
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• pp.103-106
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• 2004

We have studied a conduction mechanism and equivalent circuit analysis in $Alq_3$ based Organic Light Emitting Diode. The conduction mechanism in organic light emitting diode can be classified into three regions; ohmic region, space-charge-limited current (SCLC) region and trap-charge-limited current (TCLC) region depending on the region of applied voltage. Equivalent circuit model of organic light emitting diode can be established using a parallel combination of resistance $R_p$ and capacitance $C_p$ with a small series resistance $R_s$.

• 환경생물
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• 제23권1호
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• pp.71-88
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• 2005

강원대학교 학술림내 연엽산 일대의 딱정벌레목 군집에 관한 연구를 위하여 2004년 4월부터 9월까지 총 6회의 조사를 실시하였다. 연엽산 일대에 4개의 지점을 정하여 light trap, pitfall trap, 그리고 sweeping의 3가지 방법으로 조사한 결과 총 48과 358종 3053개체가 출현하였다. 가장 많은 종이 출현한 과는 Carabidae로 50종이 출현하였고, 다음으로 Chrysomelida 가 40종 그리고 Curculionidae가 40종의 순으로 나타났다. 지점별로는 고도가 낮고 하천이 있는 지점 4에서 가장 많은 종이 출현하였고, pitfall trap에 많은 개체수가 채집된 지점 2에서 가장 많은 개체수가 출현하였다. 월별로는 7월에 가장 많은 종수와 개체수가 출현하였다. 우점종은 Nicro-phorus (Nicrophorus) quadripunctatus (13.00%), 아우점종은 Synuchus (Synuchus) cycloderus (7.17%)이었다. 특히 환경부 보호종인 Damaster mirabilissimus mirabilissimus가 5월에 1개체 출현하였다.

• 한국응용곤충학회:학술대회논문집
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• 한국응용곤충학회 2003년도 추계 학술발표회
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• pp.52-52
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• 2003

• Journal of Ecology and Environment
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• 제41권3호
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• pp.107-113
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• 2017

Background: As the habitat changes in Korea due to climate change, the emergence of disease-mediated vectors is increasing rapidly. Thus for the surveillance of mosquito- and chigger mite-borne disease, their seasonal prevalence and species composition were investigated at seven locations in Daegu, Gunwi and Sangju. Methods: Mosquitoes were collected twice every month from five collection sites using a black light and BG sentinel traps in Daegu and Gunwi from April through November. Chigger mites were investigated twice per month from wild rodents caught with Sherman live traps in Gunwi and Sangju from April through May and September through November. Results: A total of 2,361 female mosquitoes were collected. Cowshed (626 individuals, Trap index (TI) 44.7) and Kyungpook National University campus (846 individuals, TI 60.4) in Daegu had the highest number of mosquitoes in the black light and BG sentinel trap, respectively. The mosquitoes were collected more by BG sentinel trap than the black light trap. Nine mosquito species were trapped, and the Culex pipiens complex was the most commonly mosquito (1,397 individuals, 59.2%), followed by Anopheles sinensis (554 individuals, 23.5%). Anopheles sinensis (531 individuals, 51.9%) and Culex pipiens complex (1,142 individuals, 85.4%) were the most mosquitoes from black light and BG sentinel trap, respectively. In terms of seasonal prevalence, the highest abundance was in July, with 824 individuals collected. In chigger mites, eighty-one wild rodents of five species that are hosts of chigger mites were collected; among them, 53 and 25 individuals of Apodemus agrarius and Crocidura suaveolens, respectively were trapped. Leptotrombidium pallidum was a dominant species, with 2,467 individuals collected (67.8%). Conclusions: The mosquito was the dominant species in Culex pipiens complex and the highest in July and August. Apodemus agrarius was most abundant in wild rats and Leptotrombidium pallidum was dominant in the collected chigger mites.

• Journal of the Korean Physical Society
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• 제73권12호
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• pp.1879-1883
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• 2018

We analyzed the deep-trap states of GaN/InGaN ultraviolet light-emitting diodes (UV LEDs) before and after electrical stress. After electrical stress, the light output power dropped by 5.5%, and the forward leakage current was increased. The optical degradation mechanism could be explained based on the space-charge-limited conduction (SCLC) theory. Specifically, for the reference UV LED (before stress), two sets of deep-level states which were located 0.26 and 0.52 eV below the conduction band edge were present, one with a density of $2.41{\times}10^{16}$ and the other with a density of $3.91{\times}10^{16}cm^{-3}$. However, after maximum electrical stress, three sets of deep-level states, with respective densities of $1.82{\times}10^{16}$, $2.32{\times}10^{16}cm^{-3}$, $5.31{\times}10^{16}cm^{-3}$ were found to locate at 0.21, 0.24, and 0.50 eV below the conduction band. This finding shows that the SCLC theory is useful for understanding the degradation mechanism associated with defect generation in UV LEDs.