• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2014.05a
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• pp.51-52
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• 2014

Non-destructive technique to measure internal structure and constant distribution of material can be widely used to exploration of mineral resources, identification of underground cables and buried pipelines, and diagnostic imaging in medical area. In this paper, we considered 2-dimensional EM scattering problem. Radiation pattern in far field is estimated by using some measured information obtained from near-field solutions.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.24 no.3
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• pp.324-330
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• 2013

This paper presented measurement results of scattering characteristics of dielectric barrier discharge (DBD) plasma at atmospheric pressure. In this paper, plasma actuator is fabricated by parallel connecting of basic configuration of DBD plasma actuator, then plasma could be generated by applying 14 kV, 4 kHz of high voltage generator. In order to measure the scattering characteristics of DBD plasma, in this paper, two horn antennas and vector network analyzer are used to compare the S-parameter. Because of the structure of fabricated plasma generator, different result is obtained as antenna polarization changes. When antenna polarization is parallel to electrodes of plasma generator, the scattered field is reduced by 2 dB in maximum. In addition, for parallel polarization case, PEC is set up behind the plasma generator to measure backward scattered field. When the observation angles are $40^{\circ}C$ and $60^{\circ}C$, the amount of reduced scattered field is 2 dB in maximum at 5 GHz.

• Journal of Animal Science and Technology
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• v.53 no.2
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• pp.133-138
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• 2011

Two experiments were conducted to determine the effects of supplementing different levels of kaolin (Exp. 1) and effects of age of layers and levels of kaolin (Exp. 2) on the performance, egg and shell quality parameters of laying hens. In Exp.1, 64 laying hens of 58 wks age were randomly allotted to 4 treatments of 16 hens in each. Dietary treatments were basal diet supplemented with 0.0, 0.2, 0.4 and 0.6% kaolin. In Exp. 2 96 laying hens were divided into 6 groups of 16 hens each in a 2 ${\times}$ 3 factorial arrangement (two different ages, 30 and 58 wk and three levels of kaolin, 0.0, 0.2 and 0.4%). In both the experiment there were linear decreases in feed intake (P<0.001), improvement in FCR (P<0.05), and egg production (P<0.05), with increasing dietary kolin level. Supplementation of kaolin had no effect on the egg and shell quality parameters in both experiments. Thus, it is concluded that kaolin may improve performance, and 0.2% level showed the best laying performance.

• Korean journal of applied entomology
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• v.46 no.1 s.145
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• pp.79-85
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• 2007

From the surveys of 2005 and 2006 in Korea, Trissolicus nigripedius was found in four locations, i.e., Andong, Miryang, Namhae, and Suwon, and one of the major egg parasitoids of Dolycoris baccarum. T. nigripedius was also found to parasitize two other soybean bugs, Riptortus clavatus and Piezodous hybneri, from the field collection in 2005. Host acceptance behaviors of T. nigripedius consisting of drumming, oviposition, and marking were observed and compared on five species of soybean bugs. T. nigripedius showed the complete host acceptance behaviors on the eggs of D. baccarum, P. hybneri, and Halyomorpha halys. But T. nigripedius emerged only from the eggs of D. baccarum (96%) and P. hybneri (75%) after 24 hours of exposure. T. nigripedius did not mark on the eggs of R. clavatus and Nezara antennata during the observation of behavior, hence no egg deposition was made. However, T. nigripedius parasitized 20% and killed 30% of the eggs of R. clavatus when 24 hours were given for parasitization. T. nigripedius would be a potential biological control agent of D. baccarum and P. hybneri with ability of giving additional mortality on R. clavatus in soybean field.

• Korean journal of applied entomology
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• v.25 no.4 s.69
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• pp.201-207
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• 1986

This study was conducted to investigate the host plants in greenhouse, developmental periods at different temperatures and distribution patterns on cucumber of the greenhouse whitefly, Trialeurodes vaporariorum(TV) in $1984{\sim}1985$. Host plants of 39 species belonging 27 families only in the greenhouse were recorded in 1984. Longevity of adult was 26.8 days and number of eggs per female was 305 eggs at $25^{\circ}C$. The eggs, larval and pupal periods were 8.2, 8.3, 7.5 days respectively at $25^{\circ}C$. The threshold temperature of development from egg to larva was $8.8^{\circ}C$. Survival rates from eggs to adults at $22^{\circ}C,\;25^{\circ}C,\;30^{\circ}C$ were 70.3%, 58.0% and 66.4%, respectively. Adults and eggs were found only on the apical leaves of cucumber plants within 40 days after transplanting. On the other hand, larva distributed on the middle leaves and pupa on the lower leaves.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 1999.11a
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• pp.552-554
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• 1999

Phonon scattering and impact ionization models have been presented to analyze hot carrier transport in high energy region, using full band model and Fermi's golden rule. We have investigated temperature dependent properties for impact ionization process of Si using realistic energy band structures at 77K and look. The realistic full band model, obtained from the empirical pseudopotential method with local from factors, is used to calculate scattering rate. The accurate calculation of impact ionization rate requires the use of a wavevector- and frequency-dependent dielectric function ξ ( q,$\omega$). The empirical phonon scattering rate P$\sub$ph/, is given by deriving from linear function for P$\sub$ph/ versus D(E) since the phonon scattering rate is linearly depended on density of states D(E). Impact ionization rate p,, is calculated from the first principle's theory. and fitted by modified Keldysh formula having power of above 2.

• Korean Journal of Optics and Photonics
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• v.1 no.2
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• pp.142-148
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• 1990

Surface-enhanced Raman scattering (SERS) experiment of pyridine (CsHsN) has been performed at silverpyridine interface by use of long range surface plasmon (LRSP) which is generated in the Sarid-type attenuated total reflection (A TR) structure consisting of prism. dielectric. metal and dielectric media. Generation of LRSP has ben confirmed by observing the propagation of the LRSP. Raman signal of pyridine adsorbed on a silver surface in the above layered structure has been observed and compared with the bulk Raman signal and SERS signal from the chemically adsorbed pyridine. SERS experiment by use of LRSP has not yet reported to the best of our knowledge.wledge.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.28 no.1
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• pp.42-48
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• 2017

Characteristics of ground-penetrating radar(GPR) signals for detecting buried pipes are investigated numerically. Transmitting and receiving parts of a GPR system, a subsurface soil and a plastic pipe filled with a dielectric material are modeled by using the finite-difference time-domain(FDTD) method. FDTD simulations for observing aspects of GPR signals are performed as a function of the diameter of the pipe and the permittivity of the filling material in the pipe. GPR signals scattered by a dielectric filled pipe appear as a superposition of two waves, such as the specular wave from the front convex surface of the pipe and the axial wave from the rear concave surface of the pipe. We show that the amplitude, the polarity, the delay time of two waves depend on the size of the pipe and the permittivity of the filling material in the pipe.

• Proceedings of the KSRS Conference
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• 2009.03a
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• pp.309-313
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• 2009

산불은 전세계적으로 발생하는 가장 주요한 재해현상 중 하나이다. 산불 감시나 산불에 의한 피해지역의 효과적인 관측은 피해 지역을 최소화하고, 효율적인 피해 복구 계획 수립에 매우 중요한 기초자료를 제공한다. 광학 위성 자료를 활용한 산불 피해지역 탐지가 널리 사용되고 있음에도 불구하고, 산불에 의한 연기 또는 구름 분포에 의해 종종 사용상에 제약이 있다. 본 연구에서는 2000년 4월 강원도 고성, 강릉, 삼척, 물진 지역에서 발생한 대규모 산불을 연구 대상지역으로 하여, 1998년-2000년 동안 획득된 RADARSAT-1 SAR 영상을 이용하여 산불 피해 지역 감시의 활용성을 연구하였다. 산불에 의한 산림 피해지역 관측을 위해 RADARSAT-1 SAR 영상의 후방산란관의 변화를 통한 변환 탐지를 수행하였다. 산불 피해지역에서 산불 전에 비해 산불 후에 획득된 RADARSAT-1 SAR 영상의 후방산란값이 증가하는 것으로 관측되었다. RADARSAT-1 SAR 영상으로부터 관측된 산불 피해 지역은 Landsat-7 ETM 자료와 현장 조사 자료에 의한 산불 피해 지역과 매우 상관성이 높은 것으로 관측되었다.

• Korean journal of applied entomology
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• v.27 no.2
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• pp.103-110
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• 1988

The behavior and circadian rhythm of emergence, copulation and oviposition in the Oriental tobacco budworm (Heliothis assulta Guenee) were studied to obtain the following results. More than three quarters of adults emerged within 3 hours after the light-off. It took about 33 min for an adult to expand and tan its wings after emergence. Adult male showed a sequential pattern of mating behavior, such as antennal movement, wing elevation and vibration, exten¬sion of hairpencils, and tapping of female ovipositor leading to a copulation. However, adult female revealed a rather simple behavior, such as protraction and retraction of her terminal abdomen and vibration of wings. All of the mating took place during the early part of the scotophase, with the peak from 1 hr to 2 hrs after the light-off. But the mating peak in virgin females tended to advance with age. Adult females showed the highest rate of mating among 24 hr-olds and the rate declined with age. The rate of first matings in males gave a very similar pattern to that of females. The duration of copulation was $77\pm$14min. Oviposition occurred throughout the entire scotophase, with the peak during the first 2 hrs. The most nu¬mber of eggs deposited daily was seen on the 3rd day after the mating. Mating rate, number of eggs laid and longevity we~e compared under different sex ratio. Unmated adults lived longer than mated adults.