Earticle

본 연구에서의 방사선 검출기센서는 미세 전류, 전압, 저항 등의 변화를 감지하여 증폭할 수 있는 프리엠 프(preamplifier) 신호처리 회로를 설계하였으며, 디지털 필터회로설계, 고전압 발생 장치 모듈 및 스팩트럼 분석용 회로 시스템 인터페이스 기술 등을 통해서 시스템을 개발하였다. 방사선 검출성능 평가 장비의 정확도를 측정한 결과 신호 측정 방사선 검출기의 선형성은 ±2 % 이하, 고전압 출력 특성 ±1 % 이하의 성능으로 만족한 결과를 얻었다. 신호 평가는 윈도우 환경 화면을 통해서 하드웨어를 세팅, 에너지 스펙트럼 측정, 에너지 교정 설정 및 측정 결과를 효율적으로 평가가능하였다. 또한 휴대가 가능한 방사선 측정용 장비는 저전압 출력신호를 고성능 증폭이 가능하며, 신호처리용 디지털회로 성능 개선을 통해 원자력 분야 등에 사용 가능할 것으로 판단된다.

The radiation detector sensor in this study designed a pre-amplifier signal processing circuit that can detect and amplify changes in micro-current, voltage, and resistance, and developed the system through digital filter circuit design, high voltage generator module, and spectrum analysis circuit system interface technology. As a result of measuring the accuracy of the radiation detection performance evaluation equipment, the linearity of the signal measurement radiation detector was ±2% or less, and the high voltage output characteristics were ±1% or less. Signal evaluation was able to efficiently evaluate hardware setting, energy spectrum measurement, energy calibration setting, and measurement results through the window environment screen. n addition, portable radiation measurement equipment is capable of high-performance amplification of low-voltage output signals and is expected to be used in the nuclear field by improving the performance of digital circuits for signal processing.

Fire detectors are designed to minimize loss of life from a fire alarm system as an alarm to help evacuate more quickly until the completion of the evacuation alarm should be continued. the purpose of such alarms in order to achieve the characteristic fire heat release rate reaches a certain level, or when a certain time has elapsed, when the heat detector is to be alarms to answer. Requires a quick response, it is desirable to install the sensor as much as possible, but taking into account the cost of installation problems by engineering approach to minimize the quantity and rapidity of detection capability should be increased. In order to increase the rapidity of fire detectors in a room according to the height of the sensing period is to be maintained the optimum distance of the fire detector detects characteristics should be considered. Differential spot-type heat detectors installed domestic basis, depending on the type of sensor that can detect one sensor area is limited and less than 4m ceiling height regulations and simply double the number in excess of 4m and intended to be installed

A biochip can obtain various types of genetic information over a short period of time and enable genetic analysis. A biochip needs temperature sensors to measure temperature. A resistance temperature detector temperature sensor chip, made of copper using a printed circuit board, was introduced in this study. A printed circuit board is readily usable for copper pattern design for the substrate of a biochip. To measure biochip resistance, we tested whether it was possible to accurately measure the temperature using resistances measured at room temperature and at 55, 72, 85, and 95°C in a water bath. However, in analyzing the results obtained, the printed circuit board based resistance temperature detector sensor was found to be inadequate for use as a biochip temperature sensor, although it showed potential for use as a general-purpose resistance temperature detector sensor.

Conventional leak detectors are widely based on helium gas sensors. However, the usage of hydrogen sensors in leak detectors has increased because of the high prices of helium leak detectors and the dearth in the supply of helium gas. In this study, a hydrogen leak detector was developed using solid-state hydrogen sensors. The hydrogen sensors are based on Park-Rapp probes with heterojunctions made by oxygen-ion conducting Yttria-stabilized zirconia and proton-conducting In-doped $CaZrO_3$. The hydrogen sensors were used for determining the potential difference between air and air balanced 5 ppm of $H_2$. Even though the Park-Rapp probe shows an excellent selectivity for hydrogen, the sensitivity of the sensor was low because of the low concentration of hydrogen, and the oxygen on the surface of the sensor. In order to increase the sensitivity of the sensor, the sensors were connected in series by Pt wires to increase the potential difference. The sensors were tested at temperatures ranging from $500-600^{\circ}C$.

높은 초당 프레임 속도와 낮은 영상지연을 갖는 동영상 엑스레이 디텍터의 요구조건을 만족하기 위해서는 픽셀내 포토다이오드와 금속 배선간 중첩 영역의 기생정전용량을 최소화하여야 한다. 본 연구에서는 리드아웃 박막트랜지스터, 리셋 박막트랜지스터, 그리고 포토다이오드로 픽셀이 구성된 듀오픽스^TM(duoPIX^TM) 동영상 엑스레이 영상센서를 처음으로 제시하였다. 이후 150 × 150 mm² 영상영역, 73 ㎛ 픽셀 크기, 2048 × 2048 해상도(4.2 M pixels), 최대 초당 50 프레임의 특성을 갖는 duoPIX^TM 동영상 엑스레이 디텍터를 제작하여 초당 프레임 속도, 감도, 노이즈, MTF, 영상지연과 같은 엑스레이 영상 성능을 기존 엑스레이 영상센서를 적용한 동영상 엑스레이 디텍터와 비교 평가하였다. 평가 결과 이전 연구에서 기대했던 것과 같이 duoPIX^TM 동영상 엑스레이 디텍터가 기존 동영상 엑스레이 디텍터 대비 모든 특성에서 우위의 성능을 보여 주었다.

In order to satisfy the requirements of dynamic X-ray imaging with high frame rate and low image lag, minimizing parasitic capacitance in photodiode and overlapped electrodes in pixels is critically required. This study presents duoPIX^TM dynamic X-ray imaging sensor composing of readout thin film transistor, reset thin film transistor and photodiode in a pixel. Furthermore, dynamic X-ray detector using duoPIX^TM imaging sensor was manufactured and evaluated its X-ray imaging performances such as frame rate, sensitivity, noise, MTF and image lag. duoPIX^TM dynamic X-ray detector has 150 × 150 mm² imaging area, 73 um pixel pitch, 2048 × 2048 matrix resolution(4.2M pixels) and maximum 50 frames per second. By means of comparison with conventional dynamic X-ray detector, duoPIX^TM dynamic X-ray detector showed overall better performances than conventional dynamic X-ray detector as shown in the previous study.

This paper analysised Oil-Mist-Detector applied Capacitance Sensor which protects Diesel engine & human from explosion by detecting density of oil mist distribution. Assuming that distance between oil mists is same, Capacitance sensor plates & all oil mists could be analogized to capacitors. From equivalent circuit of Oil-Mist-Detector, variation of Capacitance which is related to Oil Mist's diameter & density of oil mist distribution is obtainable.

In this paper, an efficient detection algorithm for the flicker, which is caused by mismatching between light frequency and exposure time at CMOS image sensor (CIS), is proposed. The flicker detection can be implemented by specific hardware or complex signal processing logic. However it is difficult to implement on single chip image sensor, which has pixel, CDS, ADC, and ISP on a die, because of limited die area. Thus for the flicker detection, the simple algorithm and high accuracy should be achieved on single chip image sensor,. To satisfy these purposes, the proposed algorithm organizes only simple operation, which calculates the subtraction of horizontal luminance mean between continuous two frames. This algorithm was verified with MATLAB and Xilinx FPGA, and it is implemented with Magnachip 0.18 standard cell library. As a result, the accuracy is 95% in average on FPGA emulation and the consumed gate count is about 7,500 gates (@40MHz) for implementation using Magnachip 0.18 process.

In the continuous casting process, mold level sensor control system is very important for the quality of slab & bloom, in this paper, the principle of eddy current molr level sensor was studied and a method of mold oscillation signal detecting was purposed.

본 논문에서는 고정도의 방사선 측정이 가능한 능동형 전자선량계를 제작하기 위해 필수적으로 요구되는 반도체 방사선 검출기를 ASIC으로 구현하였다. 이는 전자선량계의 소형화와 저소비전력을 실현할 수 있도록 전치증폭기와 성형증폭기를 일체화한 것으로 방사선과 방사선 검출 소자인 상용 핀 포토다이오드의 상호작용으로 생성된 수 [nA]의 전류펄스를 측정할 수 있다. MOSIS 공정을 통하여 ASIC으로 구현된 방사선검출기는 $10{\mu}Ci$의 ${\gamma}$-선 Ba-133, Cs-137 및 Co-60의 세 핵종에 대하여 방사선 조사시험을 수행하여 구현된 방사선 검출기의 유용성을 입증하였다.

This paper proposes a vehicle detector with an anisotropic magnetoresistive (AMR) sensor and addresses experimental results to show the detector's performance. The detector consists of an AMR sensor and mechanical and electronic apparatuses. The AMR sensor, composed of four magnetoresistors, senses disturbance of the earth's magnetic field caused by a vehicle moving over the sensor and then produces an output indicative of the moving vehicle. This paper verifies performance of the detector on the basis of experimental results obtained from the field tests carried under the two traffic conditions on local highways in Korea. First, I show the vehicle counting performance on a low speed congested highway by comparing the vehicle counts measured by the detector with the exact counts. Second, both vehicle counts and average speeds calculated from the measured point-occupancy on another continuously free running highway are compared with the reference values obtained from a loop detector which has two independent loop coils, where I have used several performance indices including mean absolute percentage error (MAPE) to show the performance consistency between the two types of detectors.

This paper proposed a new type of vehicle detector using a MR sensor. and addressed detector's apparatuses and detecting algorithms. Proposed detector has been tested on a local highway between Mishiryong and Sokcho in Korea. Through extensive field tests, the outputs of the detector in response to various kinds of passing vehicles have been collected and analyzed. It is verified from the analyses that the outputs of the detector take on very different aspects with each vehicle, so that information on not only traffic count but vehicle types could be extracted from the outputs. And, with the proposed detector, traffic volumes on the two lanes in the tested region were measured and compared when both congested and clear traffic situations.

This paper deals with the development, reliability, specification and performances of the ACSR inner corrosion detector system. It is designed to run on ACSR automatically and to inspect the corrosion of the line with on-line continuously. And it comprises a sensor a constant current source, a signal processing unit, a RF transmitter and receiver unit. Also separable encircling coil sensor is proposed in order to detect inner corrosion of the overhead ground wires. In conclusion, this detector can realize the nondestructive detecting of an ACSR inner corrosion.

This paper describes the design of a real time traffic data acquisition system using loop detector and piezzo sensor. Loop detector is the cheapest method to measure the speed and piezzo is used to detect the vehicle axle information. A ISA slot based I/O board is designed for data acquisition and PC process the raw traffic data and transfer the data to the host system. Simulation kit is designed with toy car kits. simulated loop detector and piezzo sensor. The data acquisition system collects up to 10 lane highway traffic data such as vehicle count. speed. length axle count. distance between the axles. The data is processed to generate traffic count, vehicle classification, which are to be used for ITS. The system architecture and simulation data is included and the system will be tested for field operation.

본 논문에서는 홈 헬스케어 환경에서 위험 동작이 발생할 경우 이를 검지하는 방법으로, 물체 검출을 위해 입력받은 영상으로 부터 배경모델을 생성하여 이를 이용해 관심 물체를 검출한다. 검출된 물체 영역 내에서 중심점의 주변 탐색을 통해 관심 물체를 추적하며, 관심 물체의 모멘트 분석 정보와 깊이 정보를 활용하여 정상 동작이 아닌 낙상과 같은 비정상적인 위험 동작이 발생되었을 경우 검출할 수 있다. 기존 비전 센서 기반 방법들은 2차원 영상 정보를 이용하기 때문에 다양한 낙상 동작에 대해 낮은 검출율을 보이고 있다. 이에 대한 개선책으로 깊이정보를 활용하여 검출함으로써 신뢰성있는 검출율을 보여주는 실시간 비전 센서 기반을 둔 위험 낙상 검출기를 제안한다.

Accidents at level crossing where railways and roads cross cause many casualties because of collision of cars etc and it also has a risk of the 2nd accident of trains. it is the most vulnerable point in the railway safety. Fundamental solution for accidents at level crossing is making the crossings cubic. but it can't be easily progressed because of environmental and financial difficulties. every kind of anti-accident measures are being strived for. one of the strived results is level crossing obstacle detector which automatically detects obstacles like defected cars etc in the middle of level crossing and transmits the information of obstacles to the approaching train. However present level crossing obstacle auto detector needs high expenses to be installed and has difficulties that lenses of beam transmitter, beam receiver should be cleaned in snowing winter. this document reviews level crossing obstacle auto detector using ultrasonic sensor to measure these difficulties.

Intravenous(IV) therapy being in use for many patients may cause serious side effects such as infiltration, extravasation. To minimize such side effects, it is important to detect symptoms appearing when fluid escapes from blood vessel to tissue as soon as possible. This paper describes a device which has been developed to detect IV infiltration early using optical sensor. The device detects IV infiltration as measuring intensity of lights reflected from that lights after emitting lights in IV therapy site. The lights are consisted of 4 different waves which provide different reflection ratio depending the fluid used in IV therapy. The experimental results show that the device can be used to detect IV infiltration early.

보상식 화재 감지기는 일정한 온도 상승률 이상으로 빠르게 상승하는 경우에 작동하는 차동식 화재 감지기의 기능과 정온점에 이르렀을 때 작동하는 정온식 화재 감지기의 기능을 모두 가진 감지기다. 이 화재 감지기는 정온점 이하에서 발생하는 화재를 감지하지 못하는 정온식 화재 감지기의 단점과 불꽃없이 천천히 타는 현상과 같이 천천히 열이 증가하는 화재를 감지하지 못하는 차동식 화재 감지기의 단점을 보완하기 위해 개발된다. 이것을 위해 우리는 이 감지기의 센서로 금속-절연체 전이 임계온도센서를 이용했는데 이 센서의 감도를 결정하는 저항온도계수가 $55^{\circ}C$일 때 14.15%로써, 서미스터(약 0.5%)보다 큰 값이다. 이 센서는 하나의 센서가 정온점 이하에서는 차동 기능, 정온점 이상에서는 정온 기능을 모두 가진다.

A Compensation-type fire detector (CFD) is operated with two functions of a differential-temperature detector and as a fixed-temperature detector. The differential-temperature detector observes a rate of temperature increase, and the fixed-temperature detector measures a given fixed temperature. The differential-temperature detector does not observe the outbreak of fire in slowly increasing temperature conditions, whereas the fixed-temperature detector is not able to observe the outbreak of fire in conditions under predetermined temperature level. We developed a CFD to compensate for weaknesses of both detectors. To compensate for the disadvantages, a sensor of the sensor metal-insulator-transition critical-temperature sensor was used. Temperature coefficient of resistance is the sensitivity for sensor. At $55^{\circ}C$, temperature coefficient of resistance of metal-insulator-transition critical-temperature sensor was 14.15%. Temperature coefficient of resistance of thermistor was about 0.5%. This CFD was operated as two ways that fixed-temperature detector and differential-temperature detector in one sensor.