Thermal Imaging Systems for Measuring Temperature Distribution

2008 ◽  
pp. 86-86-13
Author(s):  
H Kaplan
1989 ◽  
Vol 18 (1) ◽  
pp. 6-11
Author(s):  
A. K. Jaiswai ◽  
P. S. Kohli ◽  
R. N. Singh

2014 ◽  
Vol 50 (4) ◽  
pp. 402-406 ◽  
Author(s):  
V. M. Tymkul ◽  
L. V. Tymkul ◽  
Yu. A. Fes’ko ◽  
A. N. Polikanin

2021 ◽  
Vol 21 (11) ◽  
pp. 293
Author(s):  
Shan-Xiang Wei ◽  
De-Qing Kong ◽  
Qi-Ming Wang

Abstract The non-uniform temperature distribution of the main reflector of a large radio telescope may cause serious deformation of the main reflector, which will dramatically reduce the aperture efficiency of a radio telescope. To study the non-uniform temperature field of the main reflector of a large radio telescope, numerical calculations including thermal environment factors, the coefficients on convection and radiation, and the shadow boundary of the main reflector are first discussed. In addition, the shadow coverage and the non-uniform temperature field of the main reflector of a 70-m radio telescope under solar radiation are simulated by finite element analysis. The simulation results show that the temperature distribution of the main reflector under solar radiation is very uneven, and the maximum of the root mean square temperature is 12.3°C. To verify the simulation results, an optical camera and a thermal imaging camera are used to measure the shadow coverage and the non-uniform temperature distribution of the main reflector on a clear day. At the same time, some temperature sensors are used to measure the temperature at some points close to the main reflector on the backup structure. It has been verified that the simulation and measurement results of the shadow coverage on the main reflector are in good agreement, and the cosine similarity between the simulation and the measurement is above 90%. Despite the inevitable thermal imaging errors caused by large viewing angles, the simulated temperature field is similar to the measured temperature distribution of the main reflector to a large extent. The temperature trend measured at the test points on the backup structure close to the main reflector without direct solar radiation is consistent with the simulated temperature trend of the corresponding points on the main reflector with the solar radiation. It is credible to calculate the temperature field of the main reflector through the finite element method. This work can provide valuable references for studying the thermal deformation and the surface accuracy of the main reflector of a large radio telescope.


2018 ◽  
Vol 13 (3) ◽  
pp. 561-567
Author(s):  
Behzad Aliahmad ◽  
Aye Nyein Tint ◽  
Sridhar Poosapadi Arjunan ◽  
Priya Rani ◽  
Dinesh Kant Kumar ◽  
...  

Introduction: In clinical practice, both area and temperature of the ulcer have been shown to be effective in tracking the healing status of diabetes-related foot ulcer (DRFU). However, traditionally, the area of the DRFU is measured regardless of the temperature distribution. The current prospective, observational study used thermal imaging, as a more accurate tool, to measure both the area and the temperature of DRFU. We aimed to predict healing of DRFU using thermal imaging within the first 4 weeks of ulceration. Method: A pilot study was conducted where thermal and color images of 26 neuropathic DRFUs (11 healing vs 15 nonhealing) from individuals with type 1 or 2 diabetes were taken at the initial clinic visit (baseline), at week 2, and at week 4. The thermal images were segmented into isothermal patches to identify the wound boundary and area corresponding to temperature distribution. Five parameters were obtained: temperature of the wound bed, area of the isothermal patch of the wound bed, area of isothermal patch of periwound, number of isolated isothermal patches of the wound region, and physical wound bed area from color image. The ulcers were also measured by experienced podiatrists over 4 consecutive weeks and used as the healing reference. Results: For healing cases, the ratio of the area of the wound bed to its baseline measured using thermal images was found to be significantly lower at 2 weeks compared to nonhealing cases and this corresponded with a 50% reduction in area of DRFU at 4 weeks (group rank-based nonparametric analysis of variance P = .036). In comparison, neither the planimetric area measured using color images nor the temperature of the wound bed was associated with the healing. Conclusion: This study of 26 patients demonstrates that change in the isothermal area of DRFU can predict the healing status at week 4. Thermal imaging of DRFUs has the advantage of incorporating both area and temperature allowing for early prediction of the healing of these ulcers. Further studies with greater sample sizes are required to test the significance of these results.


1977 ◽  
Vol 16 (11) ◽  
pp. 2938 ◽  
Author(s):  
J. A. Savage ◽  
P. J. Webber ◽  
A. N. Pitt

2013 ◽  
Vol 13 (02) ◽  
pp. 1350045 ◽  
Author(s):  
E. F. J. RING ◽  
A. JUNG ◽  
B. KALICKI ◽  
J. ZUBER ◽  
A. RUSTECKA ◽  
...  

Infrared thermal imaging has in recent years become more accessible and affordable as a means of remote sensing for human body temperature such as in identifying a person with fever. The implementation and operational guidelines for identifying a febrile human using a screening thermograph as documented in the ISO/TR 13154:2009 ISO/TR 80600 has been deployed for the screening of a total of 402 children. It was found that there was a significant difference between the temperatures measured in non-fevered patients and those with known fever, with the thermal imaging of the eye region being the most rapid non-contact site for measurement.


1986 ◽  
Author(s):  
T. L. Williams ◽  
Lionel R. Baker ◽  
Andre Masson

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