• 대한기계학회논문집B
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• 제30권6호
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• pp.531-537
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• 2006

A lever type $NO_2$ micro gas sensor was fabricated by MEMS technology. In order to heat up the gas sensing material to a target temperature, a micro heater was built on the gas sensor. The sensing material laid on the heater and electrodes and did not contact with the silicon base to minimize the heat loss to the silicon base. The electric power to heat up the gas sensor to a target temperature was measured. The temperature distribution of micro gas sensor was analyzed by a CFD program. The predicted electric power of micro heater to heat up the sensing material to the target temperature showed a good agreement with the measured data. The design of micro gas sensor could be modified to show more uniform temperature distribution and to consume less electric power by optimizing the layout of micro heater and electrodes.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제55권5호
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• pp.278-285
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• 2006

A micro hotplate for micro gas sensor was fabricated by MEMS technology. In order to heat up the gas sensing material to a target temperature, a micro hotplate was built on the gas sensor. The sensing material was deposited on the heater and electrodes, and did not contact with the silicon base to minimize the heat loss to the silicon base. The electric power to heat up the gas sensor was measured. The temperature distribution of micro gas sensor was analyzed by a CFD program. The predicted electric power to heat up th sensing material showed a good agreement with the measured data. The design of micro gas sensor could be modified to increase the temperature uniformity and to decrease the electric power consumption by optimizing the layout of micro hotplate and electrodes.

• Current Optics and Photonics
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• 제3권6호
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• pp.541-547
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• 2019

A novel photonic crystal fiber (PCF) sensor with three D-shaped holes based on surface plasmon resonance (SPR) is analyzed in this paper. Three D-shaped holes are filled with the analyte, and the gold film is deposited on the side of three planes. The design of D-shaped holes with outward expansion can effectively solve the uniformity problem of metallized nano-coating, it is beneficial to the filling of the analyte and is convenient for real-time measurement of the analyte. Compared with the hexagonal lattice structure, the triangular arrangement of the clad air holes can significantly reduce the transmission loss of light and improve the sensitivity of the sensor. The influences of the air hole diameter, the distance between D-shaped holes and core, and the counterclockwise rotation angle of D-shaped holes on sensing performance are studied. The simulation results show that the wavelength sensitivity of the designed sensor can be as high as 10100 nm/RIU and the resolution can reach 9.9 × 10^-6 RIU.

• 디지털콘텐츠학회 논문지
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• 제16권3호
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• pp.355-363
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• 2015

본 논문에서는 ATmega기반의 스마트 제어보드를 이용하여, 지형의 경사로에 따라 실시간으로 전동휠체어의 시트를 제어하는 시스템을 제안한다. 스마트 제어보드에는 자이로 및 가속도 센서와 Tilt센서가 포함되어 있으며, 전동휠체어가 다양한 경사로 지형을 지나갈 때 실시간으로 2개의 센서를 이용하여, 지형을 파악할 수 있도록 구성되었다. 본 논문에서는 정확한 지형을 파악할 수 있도록 자이로 센서와 가속도 센서 기반에 상호보안 필터를 적용하여, 전동휠체어가 이동 중에 출력되는 센서 값의 노이즈를 해결하였다. 이를 기반으로 전동휠체어가 이동시 센서 출력 값의 노이즈로 인하여, 시트가 지속적으로 흔들리지 않고 안정적으로 시트 평행을 유지하는 것을 확인할 수 있다. 본 논문에서는 사용자의 편의를 위해 전동휠체어에 익숙하지 않은 사람들이 쉽게 제어할 수 있도록 스마트 폰 기반의 제어 플랫폼을 제공한다. 스마트 폰의 제어플랫폼은 전동휠체어의 현재 상태를 실시간으로 모니터링 할 수 있으며, 욕창 방지와 관련하여, 시트의 기울기를 임의적으로 제어할 수 있도록 도와준다.

• 센서학회지
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• 제4권1호
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• pp.15-20
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• 1995

본 논문은 시변전장을 측정할 수 있는 평판형 센서에 대하여 기술하였다. 광대역의 전장측정계를 구현하기 한 평판형 센서가 제안되었다. 측정계의 이론적인 원리와 설계방법에 대하여 제시하였으며, 교정실험 및 적용실험을 수행하였다. 교정실험을 통하여 전장측정계의 주파수대역과 감도는 $160\;[Hz]\;{\sim}\;25\;[MHz]$, 1.2 [mV/V/m] 이었다. 적용실험으로 고전압 실험실에서 임펄스전압과 진동성 과도전압에 의해 발생되는 전장을 제안된 측정장치로 측정하였으며, 측정결과는 우수하였다.

• 설비공학논문집
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• 제26권8호
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• pp.351-356
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• 2014

Typical trouble patterns in solar thermal systems include working fluid leakage and freezing other than breakdown of pump. A fluid sensor for measuring electric resistance of fluid was developed and installed at the top of the collector piping in order to check the fault of solar system. Working fluid level in the pipe was determined by measuring electric resistance from a fluid sensor. On the base of this, it was confirmed that the fluid sensor diagnoses leakage of fluid. Electric resistance of propylene glycol aqueous solution was measured in the range of $0{\sim}70^{\circ}C$ and 0~40% of concentration. The response surface analysis was performed by using a central composite design, and the regression equation was derived from the relationship between electric resistance, temperature, and concentration. Through the experiment in a real solar system, we can estimate a concentration of working fluid when a pump is not operating and predict a possibility of freezing. Finally, an effective algorithm for trouble shooting was proposed to operate and maintain the solar system.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 하계학술대회 논문집 Vol.3 No.2
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• pp.900-903
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• 2002

Partial discharges(PD) in air, corona discharges, deteriorate the insulation strength. So, it is necessary to detect PD at an early stage before the system failure and extensive damage to the equipment. PD emit signals which can be detected by applying an capacitive electric field diagnosis. In this paper, We measured signals by capacitive electric field sensor and analyzed FFT from PD, and then compared conventional electric PD detecting method to capacitive electric field diagnosis by $\Psi-q-n$, $\Psi-v-n$, $\Psi-n$, $\Psi-q$ distributions.

• 한국초전도학회:학술대회논문집
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• 한국초전도학회 2006년도 High Temperature Superconductivity Vol.XVI
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• pp.76-76
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• 2006

• 한국전기전자재료학회논문지
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• 제25권2호
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• pp.159-164
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• 2012

In this paper, it tried to develop the core sensor for detection of micro magnetic field in electric wires. The sensor is non contact type and is consisted of ferrite core for low price. To investigate their properties for variations of current, it changed the number of winding and the length of sample core, it examined, to check the live wire situation in built-in wires, electrical characteristics due to difference between electric wires and core sensor. As the results, it verified live wire situation at the number of winding(5,000) and within length of 6[cm]. Also, it obtained magnetic field magnitude decreased inverse proportion ratio to a square about difference between electric wires and core sensor.

• 센서학회지
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• 제15권4호
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• pp.231-236
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• 2006

Single-mode planar waveguide type UV sensor was fabricated using SU-8 and photochromic dye. Polymer waveguide was fabricated $10{\mu}m$ width and $2{\mu}m$ thickness for single-mode operation. The UV sensor had an absorbance with $0.0396{\sim}0.114$ absorbance/mW respectively when the 5 mm sensing area was irradiated with UV for 3 sec. And sensor had a linear properties by sensing area variation. Proposed single-mode sensor had more excellent properties of UV sensitivity than other UV sensors.