• Title/Summary/Keyword: Oxygen sensor

Search Result 308, Processing Time 0.035 seconds

A study on measurement of oxygen in a reheating furnace using TDLAS (가열로에서 TDLAS를 이용한 각대산소농도측정에 관한 연구)

  • Kim, Young-Il;Kim, Ki-Hong;Lee, In-Bum
    • 한국연소학회:학술대회논문집
    • /
    • 2006.10a
    • /
    • pp.160-167
    • /
    • 2006
  • In this project, we studied more accurate and reliable sensing method for oxygen in reheating furnace, made the empirical model for NOx concentration based on oxygen and evaluate the stability of the Tuneable Diode Laser (Absorption) Spectroscopy(TDL(A)S). The tested oxygen monitoring system is installed at work-field reheating furnace on hot roll at POSCO and compared with the Zr sensor system which shows too sensitive because it measures oxygen concentration on a spot unlike TDLS sensor which is successfully applied at 13m-width reheating furnace to measures the line average along the Optical Path Line(OPL).

  • PDF

Data processing of sensor output for correction of pressure measurement value of an anesthesia ventilator (마취기용 인공호흡기의 압력 측정값의 보정을 위한 센서 출력의 데이터 처리)

  • 박영준;이종수;김영길
    • Proceedings of the IEEK Conference
    • /
    • 1999.11a
    • /
    • pp.1067-1070
    • /
    • 1999
  • Anesthesia gas to pour to patients affects the flow and volume as the pressure difference of an oxygen and an anesthesia gas. An anesthesia gas, being injurious and polluting an environment, must control the pressure of an oxygen gas because of being used by closing up tight. But a pressure sensor to use for measuring an oxygen gas appears other pressure as the characteristic and the error difference of elements to use for implementing an system. A medical machine such as an anesthesia ventilator must be accurate because of using for the person's body. So we intend to implement an system for a sensor pressure measurement not to be change regardless of an environment. This papers is the target that a sensor pressrue measurement to be changed in environment is equal to actual sensor pressure measurement. So an implemented system is using analog filter and digital filter to reduce a noise. And we are using auto-zeroing and calibration to correct a sensor pressure which is changed in environment. Through such a process we increase the accuracy and the confidence of an anesthesia ventilator by controlling the flow of an anesthesia gas.

  • PDF

Potentiometric NOx sensors for automotive exhaust using YSZ(yittria stabilized zirconia) electrolyte (YSZ 전해질을 이용한 농담전지식 자동차용 NOx센서)

  • Park, Jin-Su;Park, Kwang-Chol;Park, C.O.
    • Journal of Sensor Science and Technology
    • /
    • v.16 no.6
    • /
    • pp.434-440
    • /
    • 2007
  • Two kinds of new NOx sensing mechanism was proposed and examined. One of those was potentiomtric sensor based on the measurement of decomposed oxygen from NO using YSZ porous diffusion barrier and Pd catalytic electrode. The sensor based on decomposed oxygen measurement responded to the range of 300 - 1000 ppm NO in $N_{2}$ environment and the sensitivities were coincident with theoretical values at 700 and $800^{\circ}C$ but the decomposition rate depended on gas flow rate. The other sensor was equilibrium potentiometric type using $Gd_{2}O_{3}$-nitrates solid solution as sensing material. The sensor using $Gd_{2}O_{3}$-nitrates solid solution was suitable for NOxxsensing at $700^{\circ}C$ in 5 % oxygen and the sensitivity was 19.3 mV/decade. However, long term stability of the sensing material at high temperature was not sufficient.

Solid-State $CO_2$ Sensor using ${Li_2}{CO_3}-{Li_3}{PO_4}-{Al_2}{O_3}$ Solid Electrolyte and ${LiMn_2}{O_4}$ as Reference Electrode (${Li_2}{CO_3}-{Li_3}{PO_4}-{Al_2}{O_3}$계의 고체 전해질 및 ${LiMn_2}{O_4}$의 기준전극을 사용한 $CO_2$ 가스센서)

  • 김동현;윤지영;박희찬;김광호
    • Journal of the Korean Ceramic Society
    • /
    • v.37 no.8
    • /
    • pp.817-823
    • /
    • 2000
  • A solid-state electrochemicall cell for sensing CO2 gas was fabricated using a solid electrolyte of Li2CO3-Li3PO4-Al2O3 mixture and a reference electrode of LiMn2O4. The e.m.f. (electromotive force) of sensor showed a good accordance with theoretical Nernst slope (n=2) for CO2 gas concentration range of 100-10000 ppm above 35$0^{\circ}C$. The e.m.f. of sensor was constant regardless of oxygen partial pressure at the high temperature above 0.1 atm. It was, however, a little depended on oxygen partial pressure as the pressure decreased below 0.1 atm. The oxygen-dependency of our sensor gradually disappeared as the operating temperature increased. The sensing behavior of our CO2 sensor was affected by the presence of water vapor, but its effect was small comparing with other sensors.

  • PDF

An Implementation of System for Control of Dissolved Oxygen and Temperature in the pools of Smart Fish Farm (스마트 양식장 수조 내 용존 산소 및 온도 제어를 위한 시스템 구현)

  • Jeon, Joo-Hyeon;Lee, Yoon-Ho;Lee, Na-Eun;Joo, Moon G.
    • IEMEK Journal of Embedded Systems and Applications
    • /
    • v.16 no.6
    • /
    • pp.299-305
    • /
    • 2021
  • Dissolved oxygen, pH, and temperature are the most important factors for fish farming because they affect fish growth and mass mortality of the fish. Therefore, fish farm workers must always check all pools on the farm, but this is very difficult in reality. That's why we developed a control system for smart fish farms. This system includes a gateway, sensor gatherers, and a PC program using LabVIEW. One sensor gatherer can cover up to four pools. The sensor gatherers are connected to the gateway in the form of a bus. For the gateway, the ATmega2560 is used as the main processor for communication and the STM32F429 is used as a sub-processor for displaying LCD. For the sensor gatherer, ATmega2560 is used as the main processor for communication. MQTT (Message Queuing Telemetry Transport), RS-485, and Zigbee are used as the communication protocols in the control system. The users can control the temperature and the dissolved oxygen using the PC program. The commands are transferred from the PC program to the gateway through the MQTT protocol. When the gateway gets the commands, it transfers the commands to the appropriate sensor gatherer through RS-485 and Zigbee.

A Study on Cerebral Blood Flow Enhancement Device Using Blood Oxygen Level Sensor (Blood Oxygen Level Sensor를 이용한 대뇌혈류증가 장치에 관한 연구)

  • Lim, Jung-Hyun;Joh, In-Hee;Kim, Young-kil
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
    • /
    • 2018.05a
    • /
    • pp.188-192
    • /
    • 2018
  • Surgery to increase cerebral blood flow is one of the treatment methods of cerebral infarction. However, invasive methods, such as surgery, may result in postoperative complications or side effects. In order to supplement this invasive method, non-invasive devices have been introduced that use human blood pressure to pressurize the extremities to increase cerebral blood flow. However, the problem of poor speed and accuracy was raised. In this paper, the perfusion index of each arm was measured by applying pressure to both arms using Blood Oxygen Level Sensor to improve the accuracy of measurement and measurement time. The pressure applied to the arm by 75% of the moment when it falls to the leg and the pressure calculated by using the pressure value obtained from the arm. Like the existing blood pressure measuring cerebral blood flow increasing device, the blood flow can be increased by more than 20% and the measurement time can be shortened, so that it can be selectively used for the patient with cerebral infarction.

  • PDF

An Experimental Study on the Secondary Waveform Analysis according to Measure of Electronic Control Waveform (가솔린엔진의 전자제어 센서파형 측정을 통한 점화2차 파형 분석에 관한 실험적 연구)

  • Yoo, Jong-Sik;Kim, Chul-Soo;Cha, Kyoung-Ok
    • Transactions of the Korean Society of Automotive Engineers
    • /
    • v.19 no.1
    • /
    • pp.95-100
    • /
    • 2011
  • The test was done on cars travelling at speeds of 20km/h, 60km/h and 100km/h, the performance testing mode for chassis dynamometer. In this test, the secondary waveform were measured, including those using faulty MAP sensors, oxygen sensors and spark plugs. The results from these measurements and their analysis of secondary waveform can be summarized as follows: 1) The secondary waveform measured from the faulty oxygen sensor showed a lot of noise around peak voltage and in the rising and falling sections during spark line which means that the air fuel mixture was non-homogeneous. 2) The secondary waveform from the faulty MAP sensor showed the worst shape compared to other sensors, including variation of spark line, state of air-fuel mixture and velocity of flame front. 3) The spark line time of secondary waveform using a faulty spark plug displayed the shortest and smallest energy spark line, which means that a misfire occurred.

A Study on Waveform Analysis of Oxygen Sensor, Injector and Secondary Waveform through Emission Characteristics by a Decrepit Vehicle (노후 차량의 배기가스 측정을 이용한 산소센서, 인젝터, 점화2차파형의 파형분석 연구)

  • Yoo, Jongsik;Kim, Chulsoo
    • Transactions of the Korean Society of Automotive Engineers
    • /
    • v.21 no.5
    • /
    • pp.151-156
    • /
    • 2013
  • The experiment was done on cars travelling at the speeds of 20km/h, 60km/h and 100km/h using the performance testing mode for chassis dynamometer. In this experiment, the relativity between the secondary waveform coming from ignition coil and exhaust emissions were measured in case of cars with failures, in oxygen sensor, spark plugs. The following results obtained by analysis of the relativity between the secondary waveform and exhaust emissions. 1) When the oxygen sensor is failure, the average value of CO emission measured was 6.8 times higher than the standard CO emission value and the average value of HC emission measured was 2.3 times higher than the standard emission level. 2) When engine parts are in failure, more fuel enters the cylinder due to longer opening duration of injector, and it tended to make CO and HC emission values increase. 3) Combustion duration, the shape of flame propagation during spark line, and the size of the discharge-induced energy were the three main elements that directly cause variations in CO and HC emission values.

Robust Nonlinear Control of Air-to-Fuel Ratio in Spark Ignition Engines

  • Myoungho Sunwoo;Paljoo Yoon;Park, Seungbum;Lee, Wootaik
    • Journal of Mechanical Science and Technology
    • /
    • v.15 no.6
    • /
    • pp.699-708
    • /
    • 2001
  • This paper presents a new approach to the AFR (Air-to-Fuel Ratio) control problem, which is based on the wide-band oxygen sensor output. The dedicated nonlinear controller is based on the feedback lineaization technique. It is well known that the feedback linearizing control technique requires an exact model of the plant for the cancellation of plant nonlinearities. A sliding mode control scheme is applied which can effectively compensate the modeling uncertainties. The measurement time delay of an oxygen sensor limits the gain of the feedback controller. Hence, time delay compensation procedure is necessary for the improvement of control performance. The Smith predictor is adopted to compensate the effects of time delay. The simulation and experimental results show that the proposed controllers can effectively reduce the transient peaks of AFR in spite of fast tip-in and tip-out maneuvers of the throttle.

  • PDF

Zirconia galvani sensor for the measurement of oxygen activity (용존산소활량 측정용 지르코니아 갈바니 센서)

  • Oh, Young-Jei
    • Journal of Sensor Science and Technology
    • /
    • v.18 no.6
    • /
    • pp.441-448
    • /
    • 2009
  • Magnesia partially stabilized zirconia(Mg-PSZ) solid electrolytes for an improvement of thermal shock resistance, which is suitable for the measurement of oxygen activity in a molten steel, were prepared by post-thermal aging treatment. The steelmaking oxygen sensor elements were formed by an injection molding method, sintered at $1650^{\circ}C$, and then thermal aged ranged from 1250 to $1400^{\circ}C$. Sintered density and porosity were decreased as increasing the magnesia content in a zirconia-magnesia solid solution. Fractions of cubic phase to the synthesized Mg-PSZ solid electrolytes were ranged from 13.13 to 79.54.% after post-thermal aging treatment. Very dense microstructure without voids in the grains was obtained by the post-thermal aging process. Fine tetragonal phase crystallites precipitated on the cubic surface during post-thermal aging up to $1300^{\circ}C$ improve a thermal shock resistance and reappearance of electro motive force(EMF) curve.