• Title/Summary/Keyword: temperature-sensitive

Search Result 1,632, Processing Time 0.03 seconds

A simulation of steady and dynamic states of methanol reforming reaction (메탄올 개질반응의 정상 및 동특성 모사)

  • 김경미;최영순;송형근
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 1989.10a
    • /
    • pp.395-398
    • /
    • 1989
  • A two dimensional pseudo-homogeneous model for the methanol reforming reaction was developed and its steady and dynamic states were studied by a computer simulation. The reactor tube diameter, the catalyst density in the fixed bed, the feed flow rate, the feed temperature and the external temperature were chosen to be adjusted to determine the length of the reactor. The dynamics of the reactor showed that the system was highly nonlinear and sensitive to the feed disturbances.

  • PDF

Characteristics of the Bacteriocin Produced from Streptococcus salivarius subsp. thermophilus (Streptococcus salivarius subsp. thermophilus가 생산하는 Bacteriocin의 특성)

  • 이장혁;장효일
    • Microbiology and Biotechnology Letters
    • /
    • v.22 no.1
    • /
    • pp.7-12
    • /
    • 1994
  • One bacterial strain, that had made the largest inhibition zone at the antagonism assay and also that lost the inhibition activity by the protease treatment, was isolated from raw milk. That strain was identified as Streptococcus salivarius subsp. thermophilus. The specific growht rate of this strain was maximum at 45$\circ $C. However, at this temperature the strain produced no bacteriocin. The bacteriocin activity was quite stable even at high temperature. Moreover, the activity of the vacteriocin was sensitive to proteases. but not to $\alpha $-amylase, DNase I, or RNase.

  • PDF

The ink jet printing of high conductivity circuits on various substrates using polymer capped nano-particle silver

  • Edwards, Charles O.;Howarth, James;James, Anthony
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 2005.07a
    • /
    • pp.814-816
    • /
    • 2005
  • In this paper, we describe how specially developed polymer capped, nano-particle silver inks can be used to print circuitry for applications like displays, RFID antennas and "disposable electronics". The requirements of printing on temperature sensitive flexible substrates (such as polymer films and papers) that require low temperature curing is also discussed.

  • PDF

써미스터의 기초지식

  • 김석현
    • 전기의세계
    • /
    • v.41 no.3
    • /
    • pp.38-42
    • /
    • 1992
  • 써미스터(THERMLISTOR)는 Thermally Sensitive Resistor의 약칭으로 온도변화에 대한 저항치의 변화가 극히 크게 변화하는 특징을 갖는 감온반도체이다. 이중에는 부특성 또는 NTC(Negative Temperature Coeffient) THERMISTOR와 정특성 또는 PTC(Positive Temperature Coeffient)THERMISTOR의 두종류와 NTC와 동일한 부의 온도계수이지만 어떤 온도영역에서 저항치가 급격히 감소하는 CTR로 분류한다. 이렇게 3가지 종류로 분류되는 THERMISTOR중 우리주변에서 가장 널리 보급되고 가정생활에서 실제로 흔히 볼수 있는 가전기기의 온도검출용 sensor로 많이 사용되고 있는 THERMISTOR SENSOR에 대해서만 기초지식을 알아보기로 하고 다음기회에는 응용기술에 대해서 알아보기로 하겠다.

  • PDF

Quasi-Distributed Temperature Sensor Based on a V-Grooved Single-Mode Optical Fiber Covered with Ethylene Vinyl Acetate

  • Kim, Kwang Taek;Jeong, Seong-Gab
    • Journal of Sensor Science and Technology
    • /
    • v.23 no.4
    • /
    • pp.229-233
    • /
    • 2014
  • In this study, a V-grooved single-mode fiber along with optical time domain reflectometry (OTDR) as a quasi-distributed temperature sensor was investigated. The external medium used to fill the V-groove affects the optical mode. The V-groove was filled with ethylene vinyl acetate (EVA) because its transmittance was sensitive to temperature. The experimental results showed that the optical loss of the sensor varies with temperature, and the sensitivity depends on the depth of the V-groove.

Measurement of the Surface Emissivity of the LED Lighting Module (LED 조명 모듈 표면의 방사율 측정에 관한 연구)

  • Park, Jin-Sung;Huh, Chang-Su
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
    • /
    • v.26 no.6
    • /
    • pp.493-501
    • /
    • 2013
  • LED lighting is sensitive because it made by semiconductor. So it has been researched about radiation of heat technologies for a long time. In addition, measurement and assessment a radiation of heat also conducted. It is necessary to get a date of accuracy temperature on the board after LED driven for measuring Junction temperature of the LED Lighting. For this research, we use 5 chip which is 4 W power on top of LED lighting board made by aluminum. Thermal camera effects to emissivity depending on material and property of the surface in LED board because it determines thermal energy which emitted from material surface. it is not only thermal camera has not a standard about emissivity. It has an error of temperature when emissivity was measured by thermal camera. we confirmed that emissivity and reflected temperature depending on color and quality of the surface throughout experiment.

The study of the high dielectric thin films for MLCC (적층형 커패시터의 응용을 위한 고유전 박막 재료의 연구)

  • 장범식;최원석;문상일;장동민;홍병유;이준신
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 2001.07a
    • /
    • pp.836-839
    • /
    • 2001
  • Ba(Zr$_{x}$Ti$_{l-x}$)O$_3$(BZT) thin films of x=0.2 and 150nm thickness were prepared on Pt/SiO$_2$/Si substrate by RF Magnetron Sputtering deposition at several temperature (40$0^{\circ}C$, 50$0^{\circ}C$, $600^{\circ}C$). As the substrates temperature increase, crystallization of the films and high dielectric constants can be obtained. Capacitance of the film deposited at high temperature is more sensitive to the applied voltage than that of the film deposited at low temperature, and the film's breakdown voltage is higher in low temperature.ure.

  • PDF

A study of Simultaneous Force and Temperature Sensing with PVDF Film (PVDF 필름을 이용한 힘과 온도 동시검지에 대한 연구)

  • Lee, Yong-Kuk;Han, Deuk-Young
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 2002.07b
    • /
    • pp.690-693
    • /
    • 2002
  • This paper is concerned on method of simultaneous force(stress) and temperature sensing with PVDF film. PVDF film has piezoelectric and pyroelectric properties. Therefore, it senses changes of stress and temperature. But it's output is affected with two properties. Using different medium in a sensing element, this problem is solved. Two structures induce different equations that its solutions are changes of stress and temperature. This method and result is applicable in skin sensor that has complexity of material and structure.

  • PDF

Quantitative Vapor Phase Exciplex Fluorescence Measurements at High Ambient Temperature and Pressure

  • Kim, Tongwoo;Jaal B. Ghandhi
    • Journal of Mechanical Science and Technology
    • /
    • v.17 no.1
    • /
    • pp.157-167
    • /
    • 2003
  • The exciplex fluorescence technique with the TMPD (tetamethyl-Ρ-phenylene-diamine) / naphthalene dopant system was applied in a combustion-type constant-volume spray chamber. A detailed set of calibration experiments has been performed in order to quantify the TMPD fluorescence signal. It has been demonstrated that the TMPD fluorescence intensity was directly proportional to concentration, was independent of the chamber pressure, and was not sensitive to quenching by either water vapor or carbon dioxide. Using a dual heated-jet experiment, the temperature dependence of TMPD fluorescence up to 1000 K was measured. The temperature field in the spray images was determined using a simple mixing model, and an iterative solution method was used to determine the concentration and temperature field including the additional effects of the laser sheet extinction. The integrated fuel vapor concentration compared favorably with the measured amount of injected fuel when all of the liquid fuel had evaporated.

High Sensitive Fiber Optic Temperature Sensor Based on a Side-polished Single-mode Fiber Coupled to a Tapered Multimode Overlay Waveguide

  • Prerana, Prerana;Varshney, Ravendra Kumar;Pal, Bishnu Pada;Nagaraju, Bezwada
    • Journal of the Optical Society of Korea
    • /
    • v.14 no.4
    • /
    • pp.337-341
    • /
    • 2010
  • A high sensitivity fiber optic temperature sensor based on a side-polished fiber (SPF) coupled to a tapered multimode overlay waveguide (MMOW) is proposed and studied. Both tapered and non-tapered MMOW were considered to study the effect of tapering of MMOW on the characteristics of the device and to investigate the criticality of the uniformity of the multimode overlay waveguide over the SPF. Present study shows that tapering of the MMOW can be used to tune the desired wavelength range without any loss in the sensitivity. Sensitivity up to 9 nm/$^{\circ}C$ within the temperature range of 25 to $100^{\circ}C$ can be achieved with the proposed sensor, almost 6 times higher compared even to state-of-the-art high-sensitivity grating-based fiber optic temperature sensors.