• Korean journal of applied entomology
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• v.40 no.2
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• pp.97-103
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• 2001

The rate of gerbera (Gerbera jamesonii Bolus.) leaf damaged by Liriomyza trifolii larvae was lower than that by adults. The adults began to be attracted to yellow sticky trap immediately after transplanting and increased gradually up to early August followed by low population density from middle to late August. In the second year, adults began to be attracted from late April after transplanting and increased abrubtly from middle May and the high density was maintained till early truly. The density decreased, however, from middle July, and then followed by the high density again early September and late October The seasonal fluctuations of larva and pupa were similar to that of adults and the peaks of pupa occurred one week later than that of larvae. Larva infected by parasitoid were observed 4 weeks after transplanting. Parasitism was 65% in average from early July to late August but decreased to 50% from early September. Number of trapped adults was the highest in the yellow sticky trap among the five different colour raps. Catches at 30~60 cm above soil surface were significantly greater than that at 90 cm.

• Proceedings of the Korean Vacuum Society Conference
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• 2015.08a
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• pp.212.1-212.1
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• 2015

본 연구에서는 용액 공정을 통해 제작한 IGZO 박막 트랜지스터의 Active layer를 적층 구조로 쌓아올리고, 신뢰성 평가를 위해 Gate에 지속적인 바이어스를 인가함으로써 소자의 문턱 전압 변화를 측정 실험을 진행하였다. Active layer 제작에 사용된 용액의 비율은 In:Zn:Ga = 1:1:30%로 제작되었고, 단일층부터 이중, 삼중층까지 적층을 하였다. 각 소자의 Active layer 층이 많아질수록 이동도가 1.21, 0.87, 0.69 ($cm^2/Vs$)으로 감소하는 등의 전기적 특성이 감소하는 경향을 보였다. 하지만 Gate에 10 V를 3000초간 지속적으로 인가해주었을 때 문턱 전압의 변화가 단일층일 때 10.4 V에서 삼중층일 때 1.3 V로 감소하였다. 이것은 Active layer의 층 사이의 계면이 형성되면서 current path에 영향을 주어 전기적 특성이 감소하였지만, 적층으로 인한 surface의 uniformity가 향상되는 것으로 확인하였다. 또한 1500초에서 Dit (Interface Trap Density)를 추출한 결과, 단일층에서는 $7.53{\times}10^{12}$($cm^{-2}-1$<)로 삼중층에서 $4.52{\times}10^{12}$($cm^{-2}-1$<)의 약 두 배 정도 높게 추출되었다.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1993.05a
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• pp.55-58
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• 1993

In this paper, the relationship between trap properties and the molecular orientation owing to elongation was investigation from TSC, electrical conductivity and X-ray diffraction was investgated. The changes of the stretching direction, from an a-axis orientation(at low elongation) to a c-axis orientation(at high elongation), as the elongation increases. were determined from X-my diffraction patterns. These results suggest that the tendency for a decrease in the trap density at a higher elongation is consistent with a continuous change of the reorientation from the a-axis to the c-axis as the elongation increases.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1994.11a
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• pp.46-49
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• 1994

In this paper we investigate the characteristics of switching and memory traps in sealed MONOS nonvolatile memory devices with different nitride thicknesses. We have demonttrated flatband voltage shift of 1V with 5V programming voltage. By fitting the experimental observations with theoretical calculations, trap density and capture cross section of memory trap at the nitride-blocking oxide interface are estimated to be 1.0${\times}$10$\^$13/ cm$\^$-2/ and 8.0${\times}$10$\^$14/ cm$\^$-2/

• Water Engineering Research
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• v.7 no.1
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• pp.29-41
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• 2006

The Imha watershed is vulnerable to severe erosion due to the topographical characteristics such as mountainous steep slopes. Sediment inflow from upland area has also deteriorated the water quality and caused negative effects on the aquatic ecosystem of the Imha reservoir. The Imha reservoir was affected by sediment-laden density currents during the typhoon 'Maemi' in 2003. The RUSLE model was combined with GIS techniques to analyze the mean annual erosion losses and the soil losses caused by typhoon 'Maemi'. The model is used to evaluate the spatial distribution of soil loss rates under different land uses. The mean annual soil loss rate and soil losses caused by typhoon 'Maemi' were predicted as 3,450 tons/km2/year and 2,920 ton/km2/'Maemi', respectively. The sediment delivery ratio was determined to be about 25% from the mean annual soil loss rate and the surveyed sediment deposits in the Imha reservoir in 1997. The trap efficiency of the Imha reservoir was calculated using the methods of Julien, Brown, Brune, and Churchill and ranges from 96% to 99%.

• JSTS:Journal of Semiconductor Technology and Science
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• v.17 no.2
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• pp.167-173
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• 2017

In this paper, the characterization of the vertical position of trapped charges in the charge-trap flash (CTF) memory is performed in the novel CTF memory cell with gate-all-around structure using technology computer-aided design (TCAD) simulation. In the CTF memories, injected charges are not stored in the conductive poly-crystalline silicon layer in the trapping layer such as silicon nitride. Thus, a reliable technique for exactly locating the trapped charges is required for making up an accurate macro-models for CTF memory cells. When a programming operation is performed initially, the injected charges are trapped near the interface between tunneling oxide and trapping nitride layers. However, as the program voltage gets higher and a larger threshold voltage shift is resulted, additional charges are trapped near the blocking oxide interface. Intrinsic properties of nitride including trap density and effective capture cross-sectional area substantially affect the position of charge centroid. By exactly locating the charge centroid from the charge distribution in programmed cells under various operation conditions, the relation between charge centroid and program operation condition is closely investigated.

• Korean journal of applied entomology
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• v.46 no.1 s.145
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• pp.117-122
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• 2007

This study was investigated the potential of ducks and fish trap for the control of golden apple snail, Pomacea canaliculata, in paddy field and water canals. The smaller size of duck (700g) preyed snails than the bigger one (1,300g). The consumption of two ducks was bigger under plastic house. They preyed over 90% on the second days of release. The release time of ducks was more effective at seven days after inoculation of snails than simultaneous. Duck could suppress the density of snails at any time from month after inoculation. Four ducks per $30m^2$ could control snails in an irrigation canals. The number of attracted golden apple snail per week was 216 in big fish trap $({\Phi}15cm)$ with menthol paste which for a carp.

• Korean journal of applied entomology
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• v.32 no.4
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• pp.389-394
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• 1993

Seasonal fluctuation of Beet armyworm, Spodoptem exigua, adults and larvae were momtored by pheromone trap and direct obseration in the welsh onion field, respecLively. Adult peaked on mid~late November and occurred 4 Limes a year by pheromone trap at Yesan, 1990. There were 3 peaks a year at Asan, 1991. The highest number of adults were caught on early September. In Suwon, the yearly number of adults caught by pheromone trap was high in the order of 1990, 1991, and 1992. In 1992, the moLh was initily caught on mid April by pheromone trap at Koheung, Chonnam, and it vms 3 month earlier than that at Suwon. The larvae of beet armyworm at welsh onion field at Asan, 1991 was first found on late June and gradually increased until mid September. The density at peak occurrence was about 20 individual per 100 hills of welsh onion. The peak of the larvae appeared 20 days after peak emergence of adult. It is expected that there are 4 times of occurrence when the first egg of beet armyworm IS laid on mid May at Suwon. It takes 48, 25, 23, and 58 days to complete 1st, 2nd, 3rd. and 4th generation, respectively.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.22 no.2
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• pp.101-106
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• 2009

In this paper, Thin films of $HfO_2$/Hf were deposited on p-type wafer by Atomic Layer Deposition (ALD). We studied the electrical and material characteristics of $HfO_2$/Hf/Si MOS capacitor depending on thickness of Hf metal layer. $HfO_2$ films were deposited using TEMAH and $O_3$ at $350^{\circ}C$. Samples were then annealed using furnace heating to $500^{\circ}C$. Round-type MOS capacitors have been fabricated on Si substrates with $2000\;{\AA}$-thick Pt top electrodes. The composition rate of the dielectric material was analyzed using TEM (Transmission Electron Microscopy), XRD (X-ray Diffraction) and XPS (X-ray Photoelectron Spectroscopy). Also the capacitance-voltage (C-V), conductance-voltage (G-V), and current-voltage (I-V) characteristics were measured. We calculated the density of oxide trap charges and interface trap charges in our MOS device. At the interface between $HfO_2$ and Si, both Hf-Si and Hf-Si-O bonds were observed, instead of Si-O bond. The sandwiched Hf metal layer suppressed the growing of $SiO_x$ layer so that $HfSi_xO_y$ layer was achieved. And finally, the generation of both oxide trap charge and interface trap charge in $HfO_2$ film was reduced effectively by using Hf metal layer.

• Korean journal of applied entomology
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• v.47 no.4
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• pp.345-352
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• 2008

The seasonal occurrence of insect pests in watermelon cultivated in greenhouses was surveyed in Gochang from 2006 to 2007 considering three seasonal types of culture: forcing culture, semi-forcing culture and retarding culture. Aphis gossypii, mites (Tetranychus urticae+T. kanzawai) and Palpita indica were the most serious pest species in watermelon greenhouse culture. A. gossypii and mites showed high density during the months of June and September in semi-forcing and retarding culture, respectively. Palpita indica was observed only in retarding culture. Leaf damage by Palpita indica was observed from the middle of August and peaked to 79.4% damage in the middle of September. Thrips and whiteflies were captured in high density by the yellow sticky trap in semi-forcing culture and retarding culture but these insects showed low population density in watermelon leaves.