• Title/Summary/Keyword: Traps

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Attracting effect of baits used in trap for swimming crab (꽃게 통발용 미끼의 유인효과)

  • Chang, Ho-Young;Koo, Jae-Geun;Lee, Keun-Woo;Cho, Bong-Kon
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.43 no.4
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    • pp.301-309
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    • 2007
  • In order to develop the artificial bait of trap for swimming crabs, the attracting effect was analyzed in the duration time of attracting effect, preference and shape recognition to the bait in the water tank and field experiments. According to the result which investigated the mean entrapped number of swimming crabs into the trap for each bait(mackerel, sardine and anchovy) in water tank experiments, the mean entrapped number was found to be higher in the trap with mackerel(6.9 ind.; 23.0%) than in other traps with sardine(5.2 ind.; 17.3%) and anchovy(3.4 ind.; 11.3%). In addition, the mean entrapped ratios of swimming crabs into the traps for 3 kinds of baits were estimated to be over 80% all in 5 hours after soaked in the water tank. For preference of swimming crabs to 3 kinds of baits, the trap with mackerel(6.9 ind.; 23.0%) was evaluated to be higher than the traps with sardine(2.8 ind.; 9.3%) and anchovy(0.2 ind.; 0.7%). In the field experiments, the mean entrapped number of swimming crabs into the trap with mackerel and sardine were found to be similar as 120 and 118 ind., but the trap with anchovy was only 85 ind.. According to the result which investigated the shape regnition of swimming crabs to the bait used mackerel, divided into 8 pieces, 16 pieces and grinded mass in water tank experiments, the mean entrapped number of swimming crabs into the traps that includes the mackerel divided into several pieces was significantly decreased. Moreover, by the presence of skin of mackerel for bait, there was a great difference in the entrapped number of swimming crabs. Therefore, it was thought that the swimming crab was attracted to the bait and entrapped into the trap would indicate that not only the chemical stimuli such as the attactant, but also the visual stimuli such as the shape recognition to the bait might be closely related.

Monitoring and Mating Disruption of Pseudococcus comstocki by Uing a Sex Pheromone in Pear Orchards (배과원에서 성페로몬을 이용한 가루깍지벌레의 발생예찰과 교미교란)

  • Cho, Young Sik;Song, Jang Hoon;Lim, Kyeong-Ho;Choi, Jin Ho;Lee, Han Chan
    • Korean journal of applied entomology
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    • v.53 no.3
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    • pp.209-215
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    • 2014
  • This study was performed to monitor the seasonal occurrence of Pseudococcus comstocki (Kuwana) by using pheromone traps and to test a mating disruption technique to control this pest in pear orchards. We compared the attractiveness of rubber septa loaded with 1.5 and 3.0 mg of the pheromone, 2,6-dimethyl-1,5-heptadien-3-yl acetate. A total of 1,021 and 1,431 males were caught in traps baited with 1.5 mg and 3 mg of the pheromone, respectively. The numbers of males caught were not affected by trap color, although yellow traps were more attractive than white traps. In 2012, P. comstocki males were captured between June and October, with peaks in late June, early August, and late September. In 2013, the males were trapped between June and October, with peaks in middle June, late July, and late September. In pheromone mating disruption tests, catches were reduced by 17.7, 65.3, and 62.9% in orchards treated with 450, 900, and 1,350 mg per 10 a of the pheromone, respectively. At harvest, 3.4, 2.9, and 4.8% of fruits in orchards treated with 450, 900, and 1,350 mg per 10 a were damaged by P. comstocki, while 9.5% were damaged in the control orchard.

Diversity and Abundance of Bark Beetles (Coleoptera, Curculionidae: Scolytinae and Platypodinae) in Deadwoods of Quercus serrata and Carpinus laxiflora (졸참나무와 서어나무 고사목의 나무좀의 다양성과 풍부도)

  • Kwon, Tae-Sung;Lee, Bong-Woo;Park, Shin-Young;Byun, Bong-Kyu;Park, Sang-Wook;Lee, Cheol-Min
    • Korean journal of applied entomology
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    • v.50 no.4
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    • pp.353-362
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    • 2011
  • This study was conducted to elucidate the patterns of occurrence of bark beetles on deadwoods of Quercus serrata Fisher and Carpinus laxiflora Blume which are expected to increase due to climate change. The survey was carried out at the LTER site in Gwangneung forest in Gyeonggi Province in 2007-2008. Bark beetles were collected using emergence traps and attraction traps (funnel trap and window trap). A total of 408 beetles belonging to 12 species in two subfamilies were collected. Platypus koryoensis (Murayama) was the most abundant species. P. koryoensis and Xylosandrus germanus (Blandford) occurred mainly in deadwoods of Q. serrata. All other species, except two rare species, occurred commonly in deadwood of both tree species. Species richness and abundance of bark beetles were higher in the attraction traps than in the emergence traps, and higher in Q. serrata than in C. laxiflora. These indexes were higher in classes I-II or I-III than in classes III-IV or IV of deadwood. Bark beetle communities differed according to years and showed a little difference between tree species.

Topics in TFT device physics and modelling

  • Migliorato, P.
    • 한국정보디스플레이학회:학술대회논문집
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    • 2005.07b
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    • pp.929-935
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    • 2005
  • This paper contains a review of methods to analise static and dynamic properties of trap states in TFTs. The Gap Density of States is extracted from C-V and I-V characteristics. Switch on transients and small signal ac measurements are used in conjunction with simulation and an analytic model to extract traps dynamic parameters.

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Efficiency of LED Trap on Controlling Tobacco Whitefly, Bemisia tabaci Adults in Greenhouse (온실에 발생하는 담배가루이 성충에 대한 LED 트랩 방제효과)

  • Jeon, Ju-Hyun;Lee, Sang-Guei;Lee, Hoi-Seon
    • Journal of Applied Biological Chemistry
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    • v.57 no.3
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    • pp.243-245
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    • 2014
  • To evaluate light-emitting diode (LED) as potential attractants for Bemisia tabaci adults, attractiveness of white and yellow LED traps were investigated in greenhouse. The yellow LED trap showed the most attractive to B. tabaci adults, followed by a similarly attraction to the white LED trap, whereas the control (no light trap) was little attractive to B. tabaci adults. These results suggested that yellow and white LED traps could be used for environment-friendly insect pest control.

Estimation of Electrical Parameters of OD Organic Semiconductor Diode from Measured I-V Characteristics

  • Moiz, Syed Abdul;Ahmed, Mansoor M.;Karimov, Kh. S.
    • ETRI Journal
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    • v.27 no.3
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    • pp.319-325
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    • 2005
  • In this paper the effect of temperature on the electrical properties of organic semiconductor disperse orange dye 25 (OD) have been examined. Thin films of OD have been deposited on $In_{2}O_{3}$ substrates using a centrifugal machine. DC current-voltage (I-V) characteristics of the fabricated devices $(Al/OD/In_{2}O_{3)$ have been evaluated at varying temperatures ranging from 40 to $60^{\circ}C$. A rectification behavior in these devices has been observed such that the rectifying ratio increases as a function of temperature. I-V characteristics observed in $Al/OD/In_{2}O_{3)$ devices have been classified as low temperature $({\leq} 50^{\circ}C)$ and high temperature characteristics (approximately $60^{\circ}C$). Low temperature characteristics have been explained on the basis of the charge transport mechanism associated with free carriers available in OD, whereas high temperature characteristics have been explained on the basis of the trapped space-charge-limited current. Different electrical parameters such as traps factor, free carrier density, trapped carrier density, trap density of states, and effective mobility have been determined from the observed temperature dependent I-V characteristics. It has been shown that the traps factor, effective mobility, and free carrier density increase with increasing values of temperature, whilst no significant change has been observed in the trap density of states.

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Influence of Endurance tests on Space Charge Distribution of 160kV HVDC XLPE Cable

  • Liu, Yun-Peng;Liu, He-Chen
    • Journal of Electrical Engineering and Technology
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    • v.12 no.1
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    • pp.302-309
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    • 2017
  • The ageing of XLPE cable insulation will lead to the accelerating accumulation of space charge, which will greatly affect the safe operation of the HVDC cable. In order to investigate the influence of different ageing modes on the space charge distribution of the HVDC cable, thermal stressed, electrical stressed and electro-thermal stressed endurance tests were carried out on the XLPE peelings. The tested XLPE peelings were obtained from 160kV HVDC cable insulation. The endurance tests were carried at thermal stress of 363K, electrical stress of 20kV/mm DC and a combination of both. The Pulsed Electro-Acoustic (PEA) method was used to measure the space charge distribution of the samples. The influences of ageing on the trap energy distribution were analyzed based on the isothermal relaxation theory and the decay characteristics of the space charge. The results showed that thermal ageing would help to improve the crystalline morphologies of the XLPE at the early stage. The total amount of space charge decreased compared to the ones before thermal ageing. The long term of electrical stress would result in the cleavage of polymer molecule chains which would intensify the accumulation of space charge and increase the density and depth of electron traps. With a combination of electrical and thermal stress, the injection and migration of space charge were more significant. Besides, the depth and density of electron traps increased rapidly with the increase of endurance time.

The Study of Deep Level Behaviors in Si Contaminated by Iron (Fe 오염에 따른 Si내의 deep level거동에 관한 연구)

  • Mun, Yeong-Hui;Kim, Jong-O
    • Korean Journal of Materials Research
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    • v.9 no.1
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    • pp.104-107
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    • 1999
  • We investigated the effects of cooling condition on deep levels and iron precipitate formation in iron-contaminated p-type silicon by DLTS(Deep Level Transient Spectroscopy) and preferential etching technique. Dependency of cooling condition on Bulk Micro-Defect (BMD) and four different iron-related deep traps were observed. For normal cooling condition, T1, T2, T3, T4 traps that related to Fe\ulcorner or Fe-O complex were obtained. However, the trap with activation energy, 0.4 eV was observed for slow cooling condition. The trap caused by the $\textrm{Fe}^{+}\textrm{}^{-}$ pair (H4:0.56eV) were detected only at the case of $\textrm{LN}_{2}$ quenching condition.

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