• 한국안전학회지
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• 제22권5호
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• pp.27-32
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• 2007

We investigated the damage of the TTL ICs which manufactured five different technologies by artificial microwave. The artificial microwave was rated at a microwave output from 0 to 1000W, at a frequency of 2.45GHz. The microwave power was extracted into a standard rectangular waveguide(WR-340) and TTL ICs were located into the waveguide. TTL ICs were damaged two types. One is breakdown which means no physical damage is done to the system and after a reset the system is going back into function. The other is destruction which means a physical damage of the system so that the system will not recover without a hardware repair. TTL SN74S08N and SN74ALS08N devices get a breakdown and destruction occurred but TTL SN74LS08N, SN74AS08N and 74F08N devices get a destruction occurred. Also destructed TTL ICs were removed their surface and a chip conditions were analyzed by SEM. The SEM analysis of the damaged devices showed onchipwire and bondwire destruction like melting due to thermal effect. The tested results expect to be applied to the fundamental data which interprets the combination mechanism of the semiconductors from artificial microwave environment.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 추계학술대회 논문집 Vol.16
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• pp.494-497
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• 2003

We report the dark spots in organic light emitting diodes by using a near-field scanning microwave microscope. Devices structure was glass / indium-tin-oxide(ITO) / copper-pthalocyiane(Cu-Pc) / tris-(8-hydroquinoline)aluminum(Alq3) / aluminum(Al). We made artificial dark spots by using a etching technique on a ITO substrate. Near-field scanning microwave microscope images and reflective coefficient of dark spots were measured and compared by the change of various applied voltage changes 0-15V.

• 정보통신설비학회논문지
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• 제9권4호
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• pp.164-167
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• 2010

In this paper, an artificial transmission line of triangular-patch type with slots is proposed. This artificial transmission line is useful for miniaturizing the electrical lengths of conventional transmission lines. Also, this structure is easy to regulate the characteristic impedance and electrical lengths. The electrical lengths and the characteristic impedances of the proposed artificial transmission line with some parameters are researched and summarized The proposed artificial transmission line could be useful for compact designs for most of the passive microwave components. The optional-artificial transmission line is fabricated and measured at 2.45GHz.

• Journal of Advanced Marine Engineering and Technology
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• 제41권1호
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• pp.70-75
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• 2017

본 논문에서는 MMIC (Monolithic microwave integrated circuit)상에서의 초소형 무선 통신 시스템에의 응용을 위해 주기적으로 배열된 다이오드를 이용한 전압제어형 전송선로(Voltage-controlled Artificial Transmission Line Employing Periodically Arrayed Diodes)의 RF특성 연구를 진행하였다. 연구 결과, 본 논문에서 제안하는 전압제어형 전송선로는 회로의 용량증가로 인해 기존의 마이크로스트립 선로의 35.2%로 단파장의 성능을 보여주었다. 그리고 유효유전율 및 전파상수는 기존의 마이크로스트립 선로보다 높은 결과를 나타냈으며, 감쇠정수 또한 기존의 전송선로에 비해 전압제어형 선로에서 높게 나타났다. 그리고 전압제어형 전송선로의 등가회로를 closed-form 방정식을 통하여 이론적으로 해석하였다.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2006년도 정기 학술대회 논문집
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• pp.35-39
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• 2006

With a growing concern about the state of infrastructure worldwide, the demand for the development of reliable nondestructive testing techniques (NDT) is ever increasing. Among possible NDT techniques. microwave method is proven to be effective in fast and non-contact inspection of concrete structures and inclusions inside concrete. It is also found that the microwave method has a potential in detecting the delamination between fiber reinforced polymer (FRP) plate and concrete. On the other hand, ultrasonic method can be another way to find the delamination. In this paper, the research work needed for the development of a reliable microwave method and ultrasonic method is studied in actual measurements of concrete specimens reinforced with FRP. Concrete specimens are made with FRP and artificial delamination inside. A microwave measurement system with horn antennas with high center frequency and broad frequency bandwidth are used to image inside concrete specimens for the detection of debonding. between concrete and FRP. Also, the equipment of ultrasonic method which is commercialized are used at the same condition. Both of the results are analyzed in comparison of each other. Microwave and ultrasonic methods have been used for the detection of debonding between concrete and fiber-reinforced plastic (FRP).

• 전기학회논문지
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• 제56권7호
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• pp.1282-1287
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• 2007

We investigated the damage of the CMOS IC which manufactured three different technologies by high power microwave. The tests separated the two methods in accordance with the types of the CMOS IC located inner waveguide. The only CMOS IC which was located inner waveguide was occurred breakdown below the max electric field (23.94kV/m) without destruction but the CMOS IC which was connected IC to line organically was located inner waveguide and it was occurred breakdown and destruction below the max electric field. Also destructed CMOS IC was removed their surface and a chip condition was analyzed by SEM. The SEM analysis of the damaged devices showed onchuipwire and bondwire destruction like melting due to thermal effect. The tested results are applied to the fundamental data which interprets the combination mechanism of the semiconductors from artificial electromagnetic wave environment and are applied to the data which understand electromagnetic wave effects of electronic equipments.

• 한국지구과학회지
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• 제31권5호
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• pp.465-474
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• 2010

Real-time rainfall monitoring is of great practical importance over the highly populated Indochina area, which is prone to natural disasters, in particular in association with rainfall. With the goal of d etermining near real-time half-hourlyrain estimates from satellite, the three-layer, artificial neural networks (ANN) approach was used to train the brightness temperatures at 6.7, 11, and $12-{\mu}m$ channels of the Japanese geostationary satellite MTSAT against passive microwavebased rain rates from Tropical Rainfall Measuring Mission (TRMM) Microwave Imager (TMI) and TRMM Precipitation Radar (PR) data for the June-September 2005 period. The developed model was applied to the MTSAT data for the June-September 2006 period. The results demonstrate that the developed algorithm is comparable to the PERSIANN (Precipitation Estimation from Remotely Sensed Information using Artificial Neural Networks) results and can be used for flood monitoring across the Indochina area on a half-hourly time scale.

• 콘크리트학회논문집
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• 제19권1호
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• pp.3-9
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• 2007

구조물의 성능평가에 대한 관심이 높아지면서 비파괴 검사 기술에 대한 요구는 계속 증가하고 있다. 이 중에서 전자파법을 이용한 비파괴 검사 기술은 콘크리트 구조물의 균열 탐사에 유용하다고 입증되어 왔고 탄소섬유 (FRP)로 보강된 콘크리트 구조물의 계면 박리를 탐사하는데도 효율적으로 쓰일 수 있을 것으로 예상되었다. 또한 초음파법을 이용한 비파괴 검사 기술도 적용 가능할 것으로 예상되었다. 이번 연구의 목적은 전자기파법 및 초음파법을 이용하여 FRP로 보강된 콘크리트 구조물의 박리를 탐사하기 위한 신뢰성 있는 기술을 개발하는데 있다. 기초 실험을 위하여 스티로폼을 이용하여 인위박리 콘크리트 보강시편을 제작하였고 측정을 실시하였다. 전자기파법을 이용한 연구에서는 기존 안테나 대신에 중심 주파수 15 GHz, 대역폭 10 GHz의 성능을 가진 혼 안테나를 사용하였고 초음파법을 이용한 연구에서는 콘크리트 균열용 상용 장비인 TR-300에 박리측정용 탐촉자를 사용하여 측정을 실시하였다. 두 가지 방법 모두 박리의 유무를 판별하는데 성공하였고 더욱 정밀한 결과를 위하여 향후 연구 방향을 제시하였다.

• JSTS:Journal of Semiconductor Technology and Science
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• 제6권3호
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• pp.182-188
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• 2006

An artificial neural network model for the microwave characteristics of an InGaAs/InP hemt for 70 nm gate length has been developed. The small-signal microwave parameters have been evaluated to determine the transconductance and drain-conductance. We have further investigated the frequency characteristics of the device. The neural network training have been done using the three layer architecture using Levenberg-Marqaurdt Backpropagation algorithm. The results have been compared with the experimental data, which shows a close agreement and the validity of our proposed model.

• Journal of Radiation Protection and Research
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• 제38권4호
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• pp.185-188
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• 2013

Heating method using electric heater was used to reduce water content in fingernail clippings. Authors found that low water content is helpful to measure EPR signal of fingernail sample with enhanced variability. Generally, natural dehydration happens in normal room condition at least one month and needs much time for using in experiment. So, artificial heating method is applied in this study for time savings. Fingernail samples were tested to find effect of water content to the EPR signal on microwave power levels for dosimetry. Low water content in fingernail reduced variability of EPR signal and makes it possible to measure accurate EPR signal. It also made it possible to measure constant movement of EPR signals on several microwave power levels. Although this method was difficult to apply directly in fingernail/EPR dosimetry, we, authors, believe that this heating method would be useful to differentiate MIS2 and RIS which are generally located at the same g-factor and almost impossible to be identified with each other.