• 마이크로전자및패키징학회지
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• 제13권4호
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• pp.65-70
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• 2006

CVD 및 PECVD법으로 탄소 나노튜브를 성장하고, 그 후 $400{\sim}500^{\circ}C$에서 산화 열처리한 센서의 이산화질소 감지특성을 $200^{\circ}C$ 및 1.5ppm의 이산화질소 농도 하에서 측정하였다. 탄소 나노튜브 센서의 전기저항은 온도 증가에 따라 감소하는 반도체 특성을 보였으며, 이산화질소 흡착에 따라 전기저항은 감소하였다. 공기 중의 수분은 센서감도에 영향을 주고 있으며, 센서를 마이크로파에 3분간 노출하면 센서의 특성은 저하되었다. 또한 CVD법으로 제조한 시편에 비하여 PECVD법으로 성장한 탄소 나노튜브 센서의 감도는 향상 되었다.

• 한국군사과학기술학회지
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• 제15권2호
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• pp.208-214
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• 2012

The spectral radiance received by a remote sensor is consisted of the self-emitted component directly from the target surface, the reflected component of the solar irradiance at the target surface, and the scattered component by the atmosphere without ever reaching the object surface. In general, the self-emitted component is the most important part in the infrared signatures from the target. We measured the solar irradiation, sky irradiation, air temperature, wind velocity, wind direction, relative humidity, and atmospheric pressure together with the surface temperatures of rectangular parallelepiped targets. The measured diurnal surface temperature variations on the three different rectangular parallelepiped targets constructed by the steel, aluminum and bakelite are obtained at the same time intervals. The measured surface temperature results show that the top surface temperature of bakelite recorded up tp $7.6^{\circ}C$ higher than that of aluminium and $6.1^{\circ}C$ higher than that of steel at 11 AM on the sunny condition. A complete set of measured data including the surface temperature of rectangular parallelepiped targets together with the detailed weather information can be a valuable reference for future study.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1998년도 추계종합학술대회 논문집
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• pp.597-600
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• 1998

When a semiconductor(pMOSFET) sensor is exposed to ionizing radiation, electrons/holes are generated in its oxide layer. By the phenomenon of hole traps in oxide layer during their move, the characteristics of semiconductor is changed. This paper describes the output characteristic changes of two kind of pMOSFET(domestic, japan) after C0-60 ${\gamma}$-irradiation on them for their application as radiation accumulated dose monitoring sensors. We found the threshold voltage shifts (VT) of pMOSFETs in proportion to irradiated radiation dose and their linear properties. These results make us confirm that we will be able to develop good accumulated radiation dose monitoring sensors.

• 세라미스트
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• 제22권1호
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• pp.27-35
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• 2019

Research on ultraviolet (UV) light detection has attracted considerable attention from scientific researchers in related fields. It can be said that it is a very important time to accurately monitor the UV irradiation amount according to the wavelength region in real time. The oxide is very diverse in its kind and has the advantage of being able to efficiently control the band gap through band gap engineering. In addition, it is very stable in response to heat and atmospheric oxygen when UV is absorbed. Also, there is a known method that can effectively manufacture oxide nanoparticles and nanorods through various synthesis methods, and researches for improving the sensitivity of UV sensors have been carried out using this method. In this paper, we introduce the materials that can be used as UV sensors among various wide band oxide materials, and review the results of researches of various UV sensors using nano materials.

• 센서학회지
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• 제22권5호
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• pp.357-363
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• 2013

An ultraviolet pulsed laser ablation of polyimide film coated with platinum has been used to enhance the sensitivity for the application as an electrochemical biosensor. Densely packed cones are formed on polyimide surface after UV irradiation which results in increase of surface area. In order to apply the sensitivity improvement of laser ablated polyimide film electrodes, the glucose oxidase modified biosensor was fabricated by using an encapsulation in the gel matrix through sol-gel transition of tetraethoxysliane on the surface of laser ablated polyimide film. The optimum conditions for glucose determination have been characterized with respect to the applied potential and pH. The linear range and detection limit of glucose detection were from 2.0 mM to 18.0 mM and 0.18 mM, respectively. The sensitivity of glucose biosensors fabricated with laser ablated polyimide film is about three times higher than that of plain polyimide film due to increase in surface area by laser ablation.

• 한국IT서비스학회지
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• 제8권2호
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• pp.147-156
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• 2009

As the result of the rapid development of IT technology, an on-line diagnostic system using the field bus communication network coupled with a smart sensor module will be widely used at the nuclear power plant in the near future. The smart sensor system is very useful for the prompt understanding of abnormal state of the key equipments installed in the nuclear power plant. In this paper, it is assumed that a smart sensor system based on the fieldbus communication network for the surveillance and diagnostics of safety-critical equipments will be installed in the harsh-environment of the nuclear power plant. It means that the key components of fieldbus communication system including microprocessor, FPGA, and ASIC devices, are to be installed in the RPV (reactor pressure vessel) and the RCS (reactor coolant system) area, which is the area of a high dose-rate gamma irradiation fields. Gamma radiation constraints for the DBA (design basis accident) qualification of the RTD sensor installed in the harsh environment of nuclear power plant, are typically on the order of 4 kGy/h. In order to use a field bus communication network as an ad-hoc diagnostics sensor network in the vicinity of the RCS pump area of the nuclear power plant, the robust survivability of IT-based micro-electronic components in such intense gamma-radiation fields therefore should be verified. An intelligent CCD camera system, which are composed of advanced micro-electronics devices based on IT technology, have been gamma irradiated at the dose rate of about 4.2kGy/h during an hour UP to a total dose of 4kGy. The degradation performance of the gamma irradiated CCD camera system is explained.

• 한국정보통신학회논문지
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• 제23권12호
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• pp.1535-1541
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• 2019

방사선 사고 지역 및 제염이 필요한 지역에서의 안전하고 신속한 제염작업을 진행하기 위해서는 방사선 오염원에 대한 다양한 정보 획득이 필요하다. 특히 방사선원의 정확한 위치와 분포 정보의 파악은 신속한 후속 조치 및 오염원 제거를 위해 반드시 필요하며, 작업자의 방사선 피폭을 최소화할 수 있다. 방사선원의 위치와 분포 정보를 획득하기 위해서는 방사선 분포 탐지 장치를 사용한다. 방사선 분포 탐지 장치의 경우 일반적으로 탐지 센서 부가 단일 센서로 구성되며, 단일 센서의 물리적 한계로 인해 탐지 범위가 제한되는 문제점이 있다. 본 논문에서는 방사선 오염 분포 영상화 장치에 사용되는 단일 센서의 탐지 감도 제어를 위하여 보정 검출기를 적용하였으며, 이를 통해 제한적이었던 선량률 탐지 범위를 향상하였다. 또한 감마선 조사 시험을 통해 방사선 분포 탐지 범위의 개선을 확인하였다.

• 한국군사과학기술학회지
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• 제13권2호
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• pp.320-327
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• 2010

The IR signature data of a ship is mainly affected by location, meteorological conditions(atmosphere temperature, wind direction and velocity, humidity etc.), atmospheric transmittance, solar position and ship surface temperature etc. The IR signatures received by a remote sensor at a given temperature and wavelength region is consisted of the self-emitted component directly from the object surface, the reflected component of the solar irradiation at the object surface, and the scattered component by the atmosphere without ever reaching the object surface. Computer simulations for prediction of the IR signatures of ships are very useful to examine the effects of various sensor positions. In this paper, we have acquired the IR signature for different sensor positions by using computer program for prediction of the IR signatures. The numerical results show that the IR signature contrast as compared to the background sea considering the meteorological conditions, solar and sky irradiations.

• Bulletin of the Korean Chemical Society
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• 제34권6호
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• pp.1632-1636
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• 2013

$Ga_2O_3$ one-dimensional (1D) nanostructures were synthesized by using a thermal evaporation technique. The morphology, crystal structure, and sensing properties of the $Ga_2O_3$ nanostructures functionalized with Pt to $NO_2$ gas at room temperature under UV irradiation were examined. The diameters of the 1D nanostructures ranged from a few tens to a few hundreds of nanometers and the lengths ranged up to a few hundreds of micrometers. Pt nanoparticles with diameters of a few tens of nanometers were distributed around a $Ga_2O_3$ nanorod. The responses of the nanorods gas sensors fabricated from multiple networked $Ga_2O_3$ nanorods were improved 3-4 fold at $NO_2$ concentrations ranging from 1 to 5 ppm by Pt functionalization. The Pt-functionalized $Ga_2O_3$ nanorod gas sensors showed a remarkably enhanced response at room temperature under ultraviolet (UV) light illumination. In addition, the mechanisms via which the gas sensing properties of $Ga_2O_3$ nanorods are enhanced by Pt functionalization and UV irradiation are discussed.

• 한국표면공학회지
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• 제41권2호
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• pp.76-82
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• 2008

We investigated sterilization characteristics of UV lights by counting the number of bacteria units with varying sterilization time and distance from the light source. We focused on an idea that UV light of 184.9 nm could generate ozone and developed a new sterilizer. The UV-ozone duplex system sterilized bacteria faster than UV-only sterilizers. To reduce shadowing effects by target objects, we used UV transparent quartz plate as a support and put a reflecting plate. Distribution of UV irradiation intensity and ozone supply were analyzed by a 3D model and measured by a semiconductor UV sensor. But even with an Al reflector, multi-layered pens could not be treated properly from UV irradiation only. Ozone generating lamp could treat more uniformly multi-layered pens with a stirring fan by supplying ozone to shadowed surfaces.