• Title/Summary/Keyword: temperature measurements

Search Result 2,772, Processing Time 0.032 seconds

Stress variation analysis based on temperature measurements at Zhuhai Opera House

  • Lu, Wei;Teng, Jun;Qiu, Lihang;Huang, Kai
    • Structural Monitoring and Maintenance
    • /
    • v.5 no.1
    • /
    • pp.1-13
    • /
    • 2018
  • The Zhuhai Opera House has an external structure consisting of a type of spatial steel, where the stress of steel elements varies with the ambient temperature. A structural health monitoring system was implemented at Zhuhai Opera House, and the temperatures and stresses of the structures were monitored in real time. The relationship between the stress distribution and temperature variations was analysed by measuring the temperature and stresses of the steel elements. In addition to measurements of the structure stresses and temperatures, further simulation analysis was carried out to provide the detailed relationship between the stress distributions and temperature variations. The limited temperature measurements were used to simulate the structure temperature distribution, and the stress distributions of all steel elements of the structure were analysed by building a finite element model of the Zhuhai Opera House spatial steel structure. This study aims to reveal the stress distributions of steel elements in a real-world project based on temperature variations, and to supply a basic database for the optimal construction time of a spatial steel structure. This will not only provide convenient, rapid and safe early warnings and decision-making for the spatial steel structure construction and operation processes, but also improve the structural safety and construction accuracy of steel space structures.

Climate change in Korea inferred from subsurface temperatures (한국의 지중온도를 이용한 기후변화연구)

  • Lee, Young-Min;Kim, Hyoung-Chan;Song, Yoon-Ho
    • 한국신재생에너지학회:학술대회논문집
    • /
    • 2006.06a
    • /
    • pp.442-444
    • /
    • 2006
  • On long time scale and over large areas ground surface temperatures (GSTs) track surface air temperatures (SATs). Additionally, GST changes penetrate into the subsurface and are recorded as transient temperature perturbation to the background thermal filed. Therefore, climate change can be reconstructed from borehole temperature measurements We present GST hi story reconstructed from temperature measurements in a borehole at Pocheon The result shows that GST cold period in the late 19th century and then increased by about 2K to 1990. GST history matches well with surface air temperatures measured from 1907 to 2001 at the Seoul Meteorological Station and GST history reconstructed from temperature measurements in three boreholes at Ulsan.

  • PDF

Structural Stability of High-Temperature State of Bacteriorhodopsin: A Model of Multi-state Membrane Proteins

  • Mitaku, Shigeki;Yokoyama, Yasunori;Sonoyama, Masashi
    • Journal of Photoscience
    • /
    • v.9 no.2
    • /
    • pp.118-121
    • /
    • 2002
  • A state of bacteriorhodopsin at high temperature was studied by various spectral measurements. The stability measurements indicated that the onset temperature of the denaturation was 70$^{\circ}C$ in the dark and 60$^{\circ}C$ under illumination. The reactivity of hydroxylamine with the Schiff's base also significantly increased in the temperature range between 60 and 70$^{\circ}C$. A spectral band at about 470 nm appeared in the temperature range higher than 60$^{\circ}C$. The circular dichroism spectra in the visible region started to change from a bilobed exiton type to a positive band at about 60$^{\circ}C$, suggesting that the two-dimensional configuration of bacteriorhodopsin molecules changed from crystalline to amorphous. All the measurements suggested a new state between 60 and 70$^{\circ}C$ in which bacteriorhodopsin is stable only in the dark.

  • PDF

The Experimental Study on Simultaneous Measurements of $O_2$ Concentration and Temperature of Flue Gas Using a Single Diode Laser (다이오드 레이저를 이용한 배기가스 $O_2$ 농도 및 온도 동시 측정에 관한 실험적 연구)

  • Kim, Se-Won;Shin, Myoung-Chul;Lee, Chang-Yeop;Youn, Sung-Woon;Kim, Young-Il
    • Journal of the Korean Society of Combustion
    • /
    • v.17 no.1
    • /
    • pp.12-21
    • /
    • 2012
  • Simultaneous measurements of oxygen concentration and temperature using diode laser in the combustion environment are successfully accomplished. A single DFB type diode laser of 760 nm line centre frequency is used and the scanned-wavelength direct absorption spectroscopy method and wavelength modulation spectroscopy method are applied to measure absorption signals below 793 K temperature region. The experimental results show that oxygen concentration are measured within 1% accuracy and temperature are measured within 5% accuracy. This new method of simultaneous measurements of concentration and temperature with a single diode laser shows a great promise.

A Study on the Errors in Skin Friction Measurements due to Surface Temperature Mismatch (표면온도 차이에 의한 표면마찰력 측정 오차에 대한 연구)

  • 백승욱
    • Journal of the Korea Institute of Military Science and Technology
    • /
    • v.3 no.2
    • /
    • pp.213-218
    • /
    • 2000
  • An experimental study was performed to investigate the effect of surface temperature mismatch on measurements of skin friction using a plug-type skin friction gage mounted on the side wall of a supersonic wind tunnel. The freestream Mach number was 2.4 and Reynolds number per meter was $5.25 {\times}10^7$ with total pressure of 50 psi and total temperature of 275K. Temperature mismatch between the gage surface and surrounding wall surface was generated by hot water injection using the active temperature control system. Results of the tests showed that the temperature mismatch made sizable effects on the measurements of skin friction.

  • PDF

Measurements of Temperature and Flow Fields with Sub-Millimeter Spatial Resolution Using Two-Color Laser Induced Fluorescence (LIF) and Micro-Particle Image Velocimetry (PIV)

  • Kim Hyun Jung
    • Journal of Mechanical Science and Technology
    • /
    • v.19 no.2
    • /
    • pp.716-727
    • /
    • 2005
  • Comprehensive measurements for velocity and temperature fields have been conducted. A Micro PIV 2-color LIF system have been setup to measure the buoyancy driven fields in a 1-mm heated channel with low Grashof-Prandtl numbers [$86]. Fluorescence microscopy is combined with an MPIV system to obtain enough intensity images and clear pictures from nano-scale fluorescence particles. The spatial resolution of the Micro PIV system is $75{\mu}m\;by\;67{\mu}m$ and error due to Brownian motion is estimated $1.05\%$. Temperature measurements have achieved the $4.7\;{\mu}m$ spatial resolution with relatively large data uncertainties the present experiment. The measurement uncertainties have been decreased down to less than ${\pm}1.0^{\circ}C$ when measurement resolution is equivalent to $76\;{\mu}m$. Measured velocity and temperature fields will be compared with numerical results to examine the feasibility of development as a diagnostic technique.

Axillary temperature measurements based on smart wearable thermometers in South Korean children: comparison with tympanic temperature measurements

  • Choi, Younglee;Ahn, Hye Young
    • Child Health Nursing Research
    • /
    • v.28 no.1
    • /
    • pp.62-69
    • /
    • 2022
  • Purpose: This study explored the validity of a new type of thermometer and parent satisfaction with the new device. This 24-hour continuous monitoring smart wearable wireless thermometer (TempTraq®) uses a very small semiconductor sensor with a thin patch-like shape. Methods: We obtained 397 sets of TempTraq® axillary temperatures and tympanic temperatures from 44 pediatric patients. Agreement between the axillary and tympanic measurements, as well as the validity of the TempTraq® axillary temperatures, were evaluated. Satisfaction surveys were completed by 41 caregivers after the measurements. Results: The TempTraq® axillary temperatures demonstrated a strong positive correlation with the tympanic temperatures. The Bland-Altman plot and analysis of TempTraq® axillary temperatures and tympanic temperatures showed that the mean difference was +0.45 ℃, the 95% limits of agreement were -0.57 to +1.46 ℃. Based on a tympanic temperature of 38 ℃, the results of validity of fever detection were sensitivity 0.85 and specificity 0.86. Satisfaction scores for TempTraq® temperature measurement were all > 4 points (satisfactory). Conclusion: TempTraq® smart axillary temperature measurement is an appropriate method for measuring children's temperatures since it was highly correlated to tympanic temperatures, had a reliable level of sensitivity and specificity, and could be used safely and conveniently.

Oceanic Skin-Bulk Temperature Difference through the Comparison of Satellite-Observed Sea Surface Temperature and In-Situ Measurements (인공위성관측 해수면온도와 현장관측 수온의 비교를 통해 본 해양 피층-표층 수온의 차이)

  • Park, Kyung-Ae;Sakaida, Futoki;Kawamura, Hiroshi
    • Korean Journal of Remote Sensing
    • /
    • v.24 no.4
    • /
    • pp.273-287
    • /
    • 2008
  • Characteristics of skin-bulk sea surface temperature (SST) differences in the Northeast Asia seas were analyzed by utilizing 845 collocated matchup data between NOAA/AVHRR data and oceanic in-situ temperature measurements for selected months from 1994 to 2003. In order to understand diurnal variation of SST within a few meters of the upper ocean, the matchup database were classified into four categories according to day-night and drifter-shipboard measurements. Temperature measurements from daytime drifters showed a good agreement with satellite MCSST (Multi-Channel Sea Surface Temperature) with an RMS error of about $0.56^{\circ}C$. Poor accuracy of SST with an rrns error of $1.12^{\circ}C$ was found in the case of daytime shipboard CTD (Conductivity, Temperature, Depth) measurements. SST differences between MCSST and in-situ measurements are caused by various errors coming from atmospheric moist effect, coastal effect, and others. Most of the remarkable errors were resulted from the diurnal variation of vertical temperature structure within a few meters as well as in-situ oceanic temperatures at different depth, about 20 cm for a satellite-tracked drifting buoy and a few meters for shipboard CTD or moored buoy. This study suggests that satellite-derived SST shows significant errors of about ${\pm}3^{\circ}C$ in some cases and therefore it should be carefully used for one's purpose on the base of in-depth understanding of skin-bulk SST difference and vertical temperature structure in regional sea.

Measurement of the Moderator Temperature Coefficient of Reactivity for Pressurized Water Reactors

  • Yu, Sung-Sik;Kim, Se-Chang;Na, Young-Whan;Kim, H. S.;J. Y. Doo;Kim, D. K.;S. W. Long
    • Nuclear Engineering and Technology
    • /
    • v.29 no.6
    • /
    • pp.488-499
    • /
    • 1997
  • The measurements of the moderator temperature coefficient (MTC) are performed to demonstrate that the calculational model produces results that are consistent with the measurements. Since negative MTC is also a technical specification value that may limit the cycle length, it is important to measure it as accurately as possible. In this report, preferred choice of test method depending on the time in cycle, best power indication and temperature definition in MTC calculation were determined based on the MTC test results taken during initial startup testing and at 2/3 cycle burnup in the Yonggwang nuclear power plant. The results show that the ratio and rodded methods provided good agreement with the predictions during initial startup testing. However, near end-of-cycle the depletion method gives better results, and so is suggested to be used in the MTC measurements at 2/3 cycle burnup. The use of primary Delta T power as a power indicator in the MTC calculations is highly advisable since it responds with good consistent results very quickly to changes unlike secondary calorimetric power. For the appropriate temperature definitions used in the MTC calculations, it is considered that the arithmetic average temperature measured simply by inlet and outlet thermocouples is preferred. Although volumetric average temperature provides better results, the improvement is not sufficient to compensate for the simplicity of calculations by arithmetic average temperature.

  • PDF

Planar Laser-Induced Fluorescence (PLIF) Measurements of a Pulsed Electrothermal Plasma Jet

  • Kim, Jong-Uk;Kim, Youn J.;Byungyou Hong
    • Journal of Mechanical Science and Technology
    • /
    • v.15 no.12
    • /
    • pp.1808-1815
    • /
    • 2001
  • The characteristics of a pulsed plasma jet originating from an electrothermal capillary discharge have been investigate using laser-induced fluorescence (LIF) measurement. Previous emission measurements of a 3.1 kJ plasma jet show trial upstream of the Mach disk the temperature and electron number density are about 14,000 K and and 10$\^$17/ cm$\^$-3/, while downstream of the Mach dick tole values are about 25,000 K and 10$\^$18/ cm$\^$-3/, respectively. However, these values are barred on line-of-sight integrated measurements that may be misleading. Hence, LIF is being used to provide both spatially and temporally resolved measurements. Our recent work has been directed at using planar laser-induced fluorescence (PLIF) imaging of atomic copper in the plasma jet flow field. Copper is a good candidate for PLIF studies because it is present throughout the plasma and has electronic transitions that provide an excellent pump-detect strategy. Our PLIF results to date show that emission measurements may give a misleading picture of the flow field, as there appeals to be a large amount of relatively low temperature copper outside the barrel shock. which may lead to errors in temperature inferred from emission spectroscopy. In this paper, the copper LIF image is presented and at the moment, relative density of atomic copper, which is distributed in the upstream of the pulsed plasma jet, is discussed qualitatively.

  • PDF