• Journal of Ecology and Environment
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• v.29 no.4
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• pp.365-379
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• 2006

Collection of moths in four Gotjawal terrains of Jeju Island was conducted using black light trap, beginning July through September 2005. The insects investigated were classified into 146 species, 15 families and 7 superfamilies, and Noctuoidea appeared to have accounted for 41.1%, or 60 species, which was the largest number among them, followed by Geometroidea. Ercheia niveostrigata was found to have been the dominant species over the entire area. The diversity index showed the highest at Aewol Gotjawal and the lowest at Hangyeong-Andeog Gotjawal. Aewol Gotjawal formed a cluster with Gujwa- Sungsan Gotjawal at the lowest chord distance (0.75). At the higher chord distance of 0.82, Jocheon- Hamdeog Gotjawal fused the cluster of Aewol Gotjawal and Gujwa-Sungsan Gotjawal. Hangyeong-Andeog Gotjawal fused with the rest three terrains, forming a single cluster at the highest chord distance of 0.89.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.07a
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• pp.531-532
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• 2005

We have used ITO/$Alq_3$/Al structure to study electrical conduction mechanism in $Alq_3$ based organic light emitting diode. Current-voltage characteristics were measured at room temperature by varying the thickness of $Alq_3$ layer from 60 to 400nm. We were able to prove that there are three different mechanism depending on the applied voltage; Ohmic, SCLC (space-charge-limited current). and TCLC (trap-charge -limited current) mechanism.

• Current Photovoltaic Research
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• v.9 no.4
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• pp.145-159
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• 2021

Light soaking (LS) stability in polymer solar cells (PSCs) has always been a challenge to achieve due to unstable photoactive layer-electrode interface. Especially, the electron transport layer (ETL) and photoactive layer interface limits the LS stability of PSCs. Herein, we have modified the most commonly used and robust zinc oxide (ZnO) ETL-interface using an organic dye molecule and a co-adsorbent. Power conversion efficiencies have been slightly improved but when these PSCs were subjected to long term LS stability chamber, equipped with heat and humidity (45℃ and 85% relative humidity), an outstanding stability in the case of ZnO/dye+co-adsorbent ETL containing devices have been achieved. The enhanced LS stability occurred due to the suppressed interfacial defects and robust contact between the ZnO and photoactive layer. Current density as well as fill factors have been retained after LS with the modified ETL as compared to un-modified ETL, owing to their higher charge collection efficiencies which originated from higher electron mobilities. Moreover, the existence of less traps (as observed from light intensity-open circuit voltage measurements and dark currents at -2V) are also found to be one of the reasons for enhanced LS stability in the current study. We conclude that the mitigation ETL-surface traps using an organic dye with a co-adsorbent is an effective and robust approach to enhance the LS stability in PSCs.

• Korean journal of applied entomology
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• v.52 no.4
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• pp.341-348
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• 2013

We desinged and evaluated a remote-sensing sex pheromone trap for real-time monitoring of Mythimna separata (Lepidoptera: Noctuidae), a migratory insect in Korea. The system consisted of a modified cone-trap with a sex pheromone lure, a sensing module based on light interruption, a signal transmission module based on code division multiple access, a main electronic board for system control, a power supply based on a solar collector, a stainless steel-pole supporting the system, and a signal collection and display system based on an internet web page. The ratio (>92%) of the actual number of insects to the signal number in the remote-sensing trap was improved by sensing only within a limited period at night on the basis of the insect's circadian rhythm, control of signal sensitivity on the basis of sensing software programming, 1-h interval for signal transmission, and adjustment of the signal transmission program. The signal occurrence pattern in the remote-sensing trap was conclusively similar (correlation coefficient, >0.98) to the actual pattern of adult occurrence in the trap. The result indicated that the remote-sensing trap based on the attraction of the sex pheromone lure for M. separata has a promising potential for practical use. Occurrence of M. separata adults was observed several times in 2011 and 2012, and the peaks were sharp.

• Electrical & Electronic Materials
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• v.9 no.7
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• pp.719-726
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• 1996

DLTS measurements were performed to study the annealing induced changes of the trap centers in MOV and to shed more light on the stability mechanism of the MOV. Two electron traps, Ec-0.26[eV] and Ec-(O.2-0.3)[eV], were observed in the unannealed samples in large quantities(7-9 X 1014[CM 3]), whereas the three electron traps Ec-0.17 [eV], Ec-0.26[eV] and Ec-(O.2-0.3)[eV] were observed far less in the annealed samples. The minima in the Ec-0.26[eV] trap density, coupled with the presented results that unannealed devices are unstable whereas 600.deg. C annealed devices are most stable, suggests that the instability of the MOV under long term electrical stressing is related to the Ec-0.26[eV] trap. This results support that the ion migration model for the device instability where the Ec-0.26[eV] defects may be the interstitial zinc or the migrating ions. The interstitial zinc originated as a result of the nonstoichiometric nature of ZnO might cause the degradation of the I-V characteristics of the MOV with long term electrical stressing.

• Design & Manufacturing
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• v.14 no.2
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• pp.42-48
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• 2020

This study is on the injection molding analysis for the LED outdoor lighting top cover of one heat sink body type structure. Thermoplastic and thermosetting resins were applied to compare the thermal properties during the injection molding process. The thermoplastic resin is used in this study due to special characteristics that it is light, good strength and dose long not transmute quality even if pass long time. The thermosetting resin is applied to this study due to good in strength, lightweight and excellent etc, thermal conductivity. This study presented a preliminary analysis of fill time, weld line, air trap etc. for the injection molding process of LED lamp cover and body through simulation using Moldflow. As a result of the study, it was selected HTM-102 material because the thermosetting resin has excellent strength and heat conductivity.

• International Commerce and Information Review
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• v.12 no.4
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• pp.509-535
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• 2010

This paper examines the Spaghetti bowl effect that different tariffs and rules of origin in multiple FTAs have resulted in increasing the significantly additional burden for business when it comes to apply for the use of FTA preference. The wide spread of FTAs in the several years, from 2003 to 2010, has been the most important trade policy development in economically important Korea. Korea presently has 5 FTAs in effect, and made 3 additional agreements which will be expected to take effect in next year. With the study result and expecting a growing number of FTAs in Korea in a next decade, the international trading firms will face rise of transaction costs for enterprises, particularly small- and medium-sized enterprises(SMEs) to cope with multiple tariffs and rule of origins in FTAs. To help mitigate negative effects and facilitate a more SEMs to use the FTA preference, providing new computer programs system, increasing the awareness of FTA provisions, improving business participation in FTA consultations, and SME support in light of education, and financial support are needed.

• Applied Microscopy
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• v.40 no.4
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• pp.237-244
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• 2010

Utricularia forms small, but complex carnivorous trap along the stem either in water or in soil depending upon species. The shapes and sizes of the traps, appendages, and trichomes are known to differ among aquatic, terrestrial and epiphytic species. In the present study, the morphology and microstructure of the trap in aquatic Utricularia japonica and terrestrial U. livida were examined using light and electron microscopy. The aim of this study was to compare the characteristics of trap features between the aquatic and terrestrial species. The trap was found to be comprised of a thin walled bladder with numerous capitate trichomes, two-armed bifid and four-armed quadrifid glands in both species; however, the traps of the two species were different in size, and number and morphology of the trichomes and glands. Aquatic Utricularia was chlorenchymatous with chloroplasts distributed throughout the body, whereas the terrestrial species was translucent without plastids due to an adaptation to underground habitats. Furthermore, the former differed considerably in that the traps developed antenna and appendages around the entrance area. A peculiar trap entrance was also noted in U. livida, which exhibited radiating rows of various trichomes within funnel-shaped tissue. A large number of glandular trichomes covered the entrance area and door surface with four trigger hairs each in the aquatic form but only two in the terrestrial form. The glandular trichomes near the door secreted a large amount of mucilage that temporarily composed the velum in the U. japonica, however, it was not observed in the terrestrial species. All of the aforementioned features were highly related in their structure and function during carnivorous mechanism in Utricularia. The current findings provide important data for further comparison of the different life forms within Utricularia.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.2 no.1
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• pp.3-9
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• 2009

Although Active matrix organic light emitting diode (AMOLED) display has a better image quality in terms of viewing angle, contrast ratio, and response time than liquid crystal displays (LCDs), it still has some critical issues such as lifetime, residual images, and brightness non-uniformity due to non-uniformity in electrical characteristics of driving TFTs and IR drops on supplied power line. Among them, we improved irrecoverable residual images of AMOLED displays which is mainly related to the hysteresis characteristics of driving TFTs. We consider four kinds of surface treatment conditions before gate oxide deposition for improving hysteresis characteristics. We can reduce the hysteresis level of p-channel TFT to 0.23 V, interface trap states between the poly-Si layer and gate insulator to $3.11{\times}10^{11}cm^{-2}$, and output current variation of p-channel TFT to 3.65 % through the surface treatment using ultraviolet light and H2 plasma. Therefore, the recoverable residual image problem of AMOLED displays can be improved by surface treatment using ultraviolet light and $H_2$ plasma.

• Journal of Applied Biological Chemistry
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• v.59 no.2
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• pp.99-102
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• 2016

The phototactic behavioral responses of Tribolium castaneum adults to light-emitting diodes (LEDs) of seven different wavelengths were determined under various conditions (light exposure times, light sources, and luminance intensities) and compared with those of a black light bulb (BLB) under laboratory conditions. Based on the attractive rate (%) of T. castaneum adults under optimal conditions (50 lx and an 48 h exposure time) in the dark, red LED ($625{\pm}10nm$) exhibited the highest potential attractive rate (97.8 %), followed by yellow ($590{\pm}5nm$, 68.9 %), green ($520{\pm}5nm$, 55.6 %), infrared (IR) (730 nm, 54.4 %), white (450-620 nm, 41.1 %), blue ($470{\pm}10nm$, 34.4 %), and ultraviolet (UV) (365 nm, 0.06 %) LEDs. In comparison, red LED (97.8 %) was approximately 3.4 times more attractive to T. castaneum adults than the BLB (28.9 %). These results indicate that a red LED trap could be useful to control T. castaneum adults.