scholarly journals Evaluation of the Size-of-Source Effect in Thermal Imaging Cameras

Sensors ◽  
2021 ◽  
Vol 21 (2) ◽  
pp. 607
Author(s):  
Igor Pušnik ◽  
Gregor Geršak
Keyword(s):  
Thermal Imaging ◽  
Region Of Interest ◽  
Thermal Imager ◽  
Direct Evaluation ◽  
Source Effect ◽  
Quantitative Measurements ◽  
Central Pixel ◽  
Custom Made ◽  
Temperature Levels

In numerous applications, including current body temperature monitoring in viral pandemic management, thermal imaging cameras are used for quantitative measurements. These require determination of the measurement accuracy (error) and its traceability (measurement uncertainty). Within error estimation, the size-of-source effect (SSE) is an important error source. The SSE is the relation between the physical size of a target and the instrument’s nominal target size. This study presents a direct evaluation of the error due to the SSE. A stable and uniform temperature, generated by blackbodies, was measured by a high-quality thermal imager. To limit the generated radiation, custom-made blocking tiles with different apertures were used. Effects of aperture shapes and positions, camera-target distances and temperature levels on the error were investigated. The study findings suggest that due to the SSE the measured temperatures are too low, especially at longer camera-target distances. The SSE error depends on the number of pixels available and included into the region of interest, for which the accurate measurement is about to be performed. For an accurate temperature measurement, an array of at least 10 × 10 pixels should be exposed to the observed target radiation, while 3 × 3 central pixel area should be included in the temperature calculation.

Investigations on skeletal growth zones via bone scans as base of determination of optimal time for surgery in mandibular asymmetry

2000 ◽  
Vol 39 (05) ◽  
pp. 121-126 ◽  
Author(s):  
R. Werz ◽  
P. Reuland
Keyword(s):  
Bone Growth ◽  
Region Of Interest ◽  
Tracer Uptake ◽  
Optimal Time ◽  
Mandibular Bone ◽  
The Third ◽  
Mandibular Asymmetry ◽  
Bone Scans ◽  
Epiphyseal Plates

Summary Aim of the study was to find out wether there is a common stop of growth of mandibular bone, so that no individual determination of the optimal time for surgery in patients with asymmetric mandibular bone growth is needed. As there are no epiphyseal plates in the mandibular bone, stop of growth cannot be determined on X-ray films. Methods: Bone scans of 731 patients [687 patients (324 male, 363 female) under 39 y for exact determination of end of growth and 44 (21 male, 23 female) patients over 40 y for evaluation of nongrowth dependant differences in tracer uptake] were reviewed for the study. All the patients were examined 3 hours after injection of 99mTc-DPD. Tracer uptake was measured by region of interest technique in different points of the mandibular bone and in several epiphyseal plates of extremities. Results: Tracer uptake in different epiphyseal plates of the extremities shows strong variation with age and good correlation with reported data of bone growth and closure of the epiphyseal plates. The relative maximum of bone activity is smaller in mandibular bone than in epiphyseal plates, which show well defined peaks, ending at 15-18 years in females and at 18-21 years in males. In contrast, mandibular bone shows no well defined end of growing but a gradually reduction of bone activity which remains higher than bone activity in epiphyseal plates over several years. Conclusion: No well defined end of growth of mandibular bone exists. The optimal age for surgery of asymmetric mandibular bone growth is not before the middle of the third decade of life, bone scans performed earlier for determination of bone growth can be omitted. Bone scans performed at the middle of the third decade of life help to optimize the time of surgical intervention.

Identification and measurement of testosterone in plasma and follicular fluid of the mare, using gas chromatography–mass spectrometry associated with isotope dilution

1983 ◽  
Vol 97 (1) ◽  
pp. 51-56 ◽  
Author(s):  
P. Silberzahn ◽  
L. Dehennin ◽  
I. H. Zwaïn ◽  
P. Leymarie
Keyword(s):  
Mass Spectrometry ◽  
Gas Chromatography ◽  
Follicular Fluid ◽  
Biosynthetic Pathway ◽  
Mammalian Species ◽  
Gas Chromatography Mass Spectrometry ◽  
Plasma Testosterone ◽  
Quantitative Measurements ◽  
Chromatography Mass Spectrometry

Testosterone has been identified by mass spectrometry in blood and follicular fluid aspirated from mature Graafian follicles of mares. Quantitative measurements made by gas chromatography–mass spectrometry have validated the determination of plasma testosterone made by radioimmunoassay. However, because of high levels of epitestosterone (17α-hydroxyandrost-4-en-3-one) in the follicular fluid, radioimmunoassay overestimates the true concentrations of testosterone. The occurrence of testosterone in mare follicular fluid at a concentration which is two orders of magnitude higher than that in peripheral plasma suggests that the follicle may contribute to the production of circulating testosterone. A biosynthetic pathway for oestradiol-17β which involves testosterone is therefore likely to occur in the mare ovary as in many other mammalian species.

scholarly journals On the ionization of light gases by X-rays. I.—Technique

1933 ◽  
Vol 141 (845) ◽  
pp. 669-686
Keyword(s):  
Absolute Intensity ◽  
X Rays ◽  
X Ray ◽  
Quantitative Correlation ◽  
Quantitative Measurements ◽  
Fluorescent Radiation ◽  
A New Technique ◽  
Heavy Gas ◽  
Reliable Correlation

The measurement of the intensity of an X-ray beam in absolute units is in theory most satisfactorily accomplished by a determination of its heating effect. The method, however, is attended by considerable experimental difficulties, so that its application is very limited, and in practice it is usual to replace it by a determination of the ionization produced when the beam is passed through a gas. To correlate the ionization with an absolute intensity requires a quantitative knowledge of the details of the interaction between the X-rays and the molecules concerned and of the ionization of the gas by the ejected electrons. It sometimes happens that the processes involved about which we know least are relatively unimportant, so that a fairly reliable correlation can be made; and much work has been done on the application of the ionization method to X-ray dosimetry. But in general a quantitative correlation between ionization and intensity is not possible. A further study of the ionization of gases by X-rays is therefore desirable; moreover it may be made to yield important information concerning the processes involved. The early development of the physics of X-rays contains many examples of this, and more recently an important contribution has been made by Stockmeyer. The events leading to the ionization of a heavy gas are exceedingly complicated, whereas in the light gases (hydrogen and helium) some of these events are absent or else occur to a negligible extent, so that the interpretation of experiments with the latter becomes simpler and more reliable. These gases are therefore specially worthy of study. Moreover, for them the application of quantum mechanics leads to the most definite results for comparison with experiment, and in particular permits of a direct test of some aspects of Dirac’s theory of recoil scattering. The ionization due to the gas itself is, however, very small, and may even be less than the secondary ionization due to electrons liberated from the chamber walls. The technique used in ionization measurements with heavy gases is therefore unsuitable. Hitherto the only attempt made to extend such measurements to light gases is an experiment carried out in 1915 on hydrogen by Shearer who, however, obtained very variable results and an ionization markedly smaller than that to be expected from recoil electrons alone. Moreover his experimental method is now open to criticism in view of our greater knowledge of X-rays, and in particular the fluorescent radiation used was of doubtful homogeneity. The present paper will describe a new technique suitable for quantitative measurements of the ionization produced by X-rays in light gases, and in another paper it will be applied to a re-investigation of hydrogen.

The hyperspectral thermal imager: High spectral and spatial resolution thermal imaging from a 6U platform

2021 ◽  
Author(s):  
Robert Wright ◽  
Paul Lucey ◽  
Miguel Nunes ◽  
Sarath Gunapala ◽  
Sir Rafol ◽  
...  
Keyword(s):  
Spatial Resolution ◽  
Thermal Imaging ◽  
Thermal Imager

scholarly journals Robust Traffic Light and Arrow Detection Using Digital Map with Spatial Prior Information for Automated Driving

Sensors ◽  
2020 ◽  
Vol 20 (4) ◽  
pp. 1181
Author(s):  
Keisuke Yoneda ◽  
Akisuke Kuramoto ◽  
Naoki Suganuma ◽  
Toru Asaka ◽  
Mohammad Aldibaja ◽  
...  
Keyword(s):  
Urban Areas ◽  
Spatial Information ◽  
Recognition Performance ◽  
Computational Cost ◽  
Region Of Interest ◽  
Traffic Light ◽  
Automated Driving ◽  
Digital Map ◽  
Traffic Lights

Traffic light recognition is an indispensable elemental technology for automated driving in urban areas. In this study, we propose an algorithm that recognizes traffic lights and arrow lights by image processing using the digital map and precise vehicle pose which is estimated by a localization module. The use of a digital map allows the determination of a region-of-interest in an image to reduce the computational cost and false detection. In addition, this study develops an algorithm to recognize arrow lights using relative positions of traffic lights, and the arrow light is used as prior spatial information. This allows for the recognition of distant arrow lights that are difficult for humans to see clearly. Experiments were conducted to evaluate the recognition performance of the proposed method and to verify if it matches the performance required for automated driving. Quantitative evaluations indicate that the proposed method achieved 91.8% and 56.7% of the average f-value for traffic lights and arrow lights, respectively. It was confirmed that the arrow-light detection could recognize small arrow objects even if their size was smaller than 10 pixels. The verification experiments indicate that the performance of the proposed method meets the necessary requirements for smooth acceleration or deceleration at intersections in automated driving.

Dermatoglyphics in Twins

1973 ◽  
Vol 22 (1) ◽  
pp. 91-98 ◽  
Author(s):  
Heloisa F. Peña ◽  
F.M. Salzano ◽  
Sidia M. Callegari
Keyword(s):  
Correlation Coefficients ◽  
The Other ◽  
Ridge Count ◽  
Genetic Determination ◽  
Qualitative Traits ◽  
Quantitative Measurements ◽  
Other Hand ◽  
Adult Twins

SummaryThe degree of genetic determination of 4 digital and 16 palmar characteristics was investigated in an unselected series of 49 MZ and 51 DZ adult twins. Low indications of heritability were obtained for the qualitative traits, but 6 of the 8 h2 estimates calculated for the quantitative measurements gave values above 0.70. In general, the results reported here are in agreement with those presented by other authors; however, the correlation coefficients observed for the A′d ridge count were lower than those of two other series. All palmar ridge counts seemed to be intercorrelated in a given individual; other expected relationships, however, were not observed. The fingerprints of MZ and DZ twins on the other hand, showed an unexplained difference.

An integral which occurs in statistics

1933 ◽  
Vol 29 (2) ◽  
pp. 271-276 ◽  
Author(s):  
A. E. Ingham
Keyword(s):  
Real Number ◽  
Positive Definite ◽  
Direct Evaluation ◽  
Independent Variables ◽  
Symmetrical Matrices ◽  
Image Position

1. In this note we give a direct evaluation of the integralwhose value has been inferred from the theory of statistics. Here A = Ap = (αμν) and C = Cp = (Cμν) are real symmetrical matrices, of which A is positive definite; there are ½ p (p + 1) independent variables of integration tμν (1 ≤ μ ≤ ν ≤ p), and tμν is written also as tνμ for symmetry of notation; in the summation ∑ the variables μ, ν run independently from 1 to p; k is a real number. A word of explanation is necessary with regard to the determination of the power |A − iT|−k. Since A is positive definite and T real and symmetric, the roots of the equation

THE PROCESS OF THERMAL IMAGING INSPECTION OF BUILDING ENVELOPES

2020 ◽  
Vol 12 (4) ◽  
pp. 66-72 ◽  
Author(s):  
Aleksandr Ignatyuk ◽  
S. Nikolenko ◽  
Svetlana Sazonova
Keyword(s):  
Heat Flux ◽  
Energy Efficiency ◽  
Thermal Imaging ◽  
Heat Flux Density ◽  
Thermal Imager ◽  
Federal Law ◽  
Building Envelopes ◽  
Digital Thermometer ◽  
The Russian Federation ◽  
Energy Survey

The paper analyzes and develops proposals to improve the energy efficiency of the building of MBOU «Lyceum No. 65» in Voronezh. The energy survey was carried out in order to comply with the requirements of Article 13 of Federal Law of November 23, 2010 No. 261-ФЗ «On Energy Saving and on Improving Energy Efficiency and on Amending Certain Legislative Acts of the Russian Federation». The survey was carried out using a Testo 881-2 thermal imager, a digital thermometer Testo 905-T2, a meter of heat flux density and ITP temperature - MG4.03 / 5 (I) «Potok».

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