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Simple Summary: Rectal thermometry is still standard practice in the measurement of body temperature in livestock because of its low cost. However, there are situations where this method is contraindicated or impractical, and a less invasive method is required. Non-contact devices have been used in livestock production; however, there are few studies about the variation and correlations in body temperature between rectal temperature and non-contact devices. The present work aims to compare rectal temperature with two types of non-contact devices (non-contact infrared thermometers and thermal imaging/infrared thermography) for the assessment of body temperature in healthy sheep. Except for the temperature taken by non-contact infrared thermometers at the muzzle, the correlation between rectal temperature vs. non-contact infrared thermometers or thermal imaging/infrared thermography showed a low significance or was difficult to use for practical flock management purposes. In addition, the variability between devices was high, which implies that measurements should be interpreted with caution in warm climates and open pens, such as most sheep farms in the Spanish Mediterranean area. Non-contact devices have been used in the measurement of body temperature in livestock production as a tool for testing disease in different species. However, there are few studies about the variation and correlations in body temperature between rectal temperature (RT) and non-contact devices such as non-contact infrared thermometers (NCIT) and thermal imaging/infrared thermography (IRT). The objective of this work was to evaluate the accuracy of non-contact devices to measure the body temperature in sheep, considering six body regions and the possibility of implementing these systems in herd management. The experiment was carried out at the experimental farm of the Catholic University of Valencia, located in the municipality of Massanassa in July of 2021, with 72 dry manchega ewes, and we compared the rectal temperature with two types of non-contact infrared devices for the assessment of body temperature in healthy sheep. Except for the temperature taken by NCIT at the muzzle, the correlation between RT vs. NCIT or IRT showed a low significance or was difficult to use for practical flock management purposes. In addition, the variability between devices was high, which implies that measurements should be interpreted with caution in warm climates and open pens, such as most sheep farms in the Spanish Mediterranean area. The use of infrared cameras devices to assess body temperature may have a promising future, but in order to be widely applied as a routine management method on farms, the system needs to become cheaper, simpler in terms of measurements and quicker in terms of analyzing results. [ABSTRACT FROM AUTHOR]

Background and Aim: Body temperature is a vital sign that determines physical status. Infrared thermography (IRT) is more frequently used for assessing horses’ temperature because of its ease of use and less contact with the horses, making it a safer measurement method. However, the accuracy of IRT remains unclear; therefore, this study aimed to assess the potential use of IRT as an alternative method for measuring horse body temperature. Materials and Methods: Temperatures were measured in 14 horses. A digital thermometer was used to collect rectal temperature (RT), whereas a thermographic camera was used for IRT at three different positions to obtain the center of body temperature (CBT), head temperature (HT), and eye temperature (ET). The protocol was performed over 30 days, repeated thrice daily: morning (6:00–8:00), afternoon (14:00–15:00), and evening (17:00–19:00). Environmental factors, including humidity, ambient temperature, wind flow, and light intensity, were recorded indirectly according to the time of day and cooling device use. Results: Mean RT, CBT, HT, and ET were 37.33°C, 34.08°C, 35.02°C, and 35.14°C, respectively. Center of body temperature was lower than RT by an average of 3.24°C (95% confidence interval [CI], 5.4°C–1.09°C). HT was lower than RT by an average of 2.3°C (95% CI, 4.33–0.28). The eye position showed the least difference between RT and infrared temperature, with an average of 2°C (95% CI, 0.7–3.92). However, there was no significant correlation between RT and infrared temperature at any position. Spray and vaporizer use significantly affected IRT and time of day (p = 0.05). Conclusion: Although IRT has advantages in terms of non-invasiveness and reduced stress on horses, its accuracy and reliability may be compromised by environmental variables, which interfere with infrared measurement. Future research should specifically focus on investigating environmental factors. [ABSTRACT FROM AUTHOR]

In recent years, non-contact infrared thermometers (NCITs) and infrared thermography (IRT) have gained prominence as convenient, non-invasive tools for human body temperature measurement. Despite their widespread adoption in a range of settings, there remain questions about their accuracy under varying conditions. This systematic review sought to critically evaluate the performance of NCITs and IRT in body temperature monitoring, synthesizing evidence from a total of 72 unique settings from 32 studies. The studies incorporated in our review ranged from climate-controlled room investigations to clinical applications. Our primary findings showed that NCITs and IRT can provide accurate and reliable body temperature measurements in specific settings and conditions. We revealed that while both NCITs and IRT displayed a consistent positive correlation with conventional, contact-based temperature measurement tools, NCITs demonstrated slightly superior accuracy over IRT. A total of 29 of 50 settings from NCIT studies and 4 of 22 settings from IRT studies achieved accuracy levels within a range of ±0.3 °C. Furthermore, we found that several factors influenced the performance of these devices. These included the measurement location, the type of sensor, the reference and tool, individual physiological attributes, and the surrounding environmental conditions. Our research underscores the critical need for further studies in this area to refine our understanding of these influential factors and to develop standardized guidelines for the use of NCITs and IRT. [ABSTRACT FROM AUTHOR]

Accurate temperature measurements are critical in manufacturing, affecting both product quality and energy consumption. At elevated temperatures, non-contact thermometers are often the only option. However, such instruments require prior knowledge of the surface emissivity, which is often unknown or difficult to determine, leading to large errors. Here we present a novel imaging luminescence thermometer based on the intensity ratio technique using magnesium fluorogermanate phosphor, with the potential to overcome this limitation. We describe measurements performed on a number of engineering alloys undergoing heat treatment at temperatures of up to 750 °C and compare these measurements against a traditional contact thermocouple and thermal imager system. Agreement between the luminescence and embedded thermocouple temperatures was found to be better than 45 °C at all temperatures. However, the thermal imager measurement on the bare metal samples, with the instrument emissivity set to 1.0, showed differences of up to 500 °C at 750 °C, a factor of 10 larger. In an effort to improve the thermal imager accuracy, its instrument emissivity was adjusted until its temperature agreed with that of the thermocouple. When measuring on the bare metal, the effective emissivity was strongly sample dependent, with mean values ranging from 0.205 to 0.784. Since the phosphor derived temperatures exhibited substantially smaller errors compared to the thermal imager, it is suggested that this method can be used to compliment the thermal imaging technique, by providing a robust mechanism for adjustment of the instrument emissivity until agreement between the thermal imager and phosphor thermometer is obtained. [ABSTRACT FROM AUTHOR]

• Application of IRT method to estimate complex phase diagrams. • Detection of complex phase transitions and data treatment automation. • IRT results comparison with DSC measurements, literature and a thermodynamic model. • IRT method limiting factors and influence parameters assessment. Phase diagrams are a primordial tool in materials science, gathering key information for the materials synthesis and the understanding of their formation processes. Numerous experimental techniques exist to determine the phase diagram of a binary system but they are time-consuming. The previously developed IRT method (InfraRed Thermography) enabled the fast determination of preliminary phase diagrams of polyols binary systems in which only liquid-solid and eutectic transitions occur. This method thus allows accelerating their screening step which is crucial before each development of a new material. This work aims at improving the transitions detection and at adapting the IRT-method to more complex phase diagrams containing eutectic, peritectic and metatectic transitions. To do so, the phase diagram of the capric-palmitic fatty acids binary system is experimentally determined using the improved IRT-method. It is then compared with those obtained using standard Differential Scanning Calorimetry measurements (DSC) and an improved thermodynamic model. Eventually, the limiting factors and the parameters of influence such as the material droplet size, as well as the nature and roughness of the substrate are investigated and discussed. [ABSTRACT FROM AUTHOR]

Hot surfaces in ship engine rooms are the risk objects that most frequently contribute to fire ignition. Thermography, especially when using thermal cameras, offers many advantages over more common infrared thermometers, but dedicated systems are often prohibitively expensive. An affordable hybrid approach was thus tested in this study, where a low-cost thermal camera smartphone was paired with a common infrared thermometer. Measurements were taken in situ during a sea voyage in an engine room under normal operating conditions, and the surfaces of the main engine, the generating set auxiliary engine, and the exhaust gas boiler were tested. Several areas were discovered to be well above the generally-accepted temperature limit of 220°C, primarily due to absent or poor insulation. Clear recommendations for remediation are made, and the proposed testing method offers fast, easy, effective, and affordable inspection. [ABSTRACT FROM AUTHOR]

Abstract Convection of a magnetic fluid within a perspex container was investigated experimentally and complemented by a computational Finite-Element model built according to the same physical specification. The enclosure was heated at two opposite side walls and exposed to a magnetic field provided by a Neodymium-Iron-Boron permanent magnet placed either above or below the container. The spatial temperature distribution on the front side wall of the container was recorded via infrared thermography (IR) and compared to computational results that reproduced the spatial temperature fields. The results show a significant effect on heat transfer by the location of the permanent magnet and gave evidence that the Kelvin body force can be much stronger than buoyancy. As both body forces are temperature sensitive an increase in temperature difference increased both, buoyancy and Kelvin body force, albeit with a different intensity that was explained via Curie's Law and expressed as a temperature dependent magnetisation through the pyromagnetic coefficient, K. The heat transfer was characterised by the Nusselt number and a suitable modified Rayleigh number that took the orientation of both buoyancy and Kelvin body force in account. The degree of heat transfer enhancement reported varied between a 23% reduction to a 20% enhancement. [ABSTRACT FROM AUTHOR]

Summary: The commercialization of polymer electrolyte membrane fuel cells has been hindered by durability problems caused by defects in the manufacturing process. We demonstrate for the first time a non‐destructive, non‐contact method that uses optical microscopy and image analysis to identify defects that may lead to failure in catalyst‐coated membranes (CCMs) of polymer electrolyte membrane fuel cells. This method is applied to 2 commercial CCMs produced by the decal transfer technique. Defects in the catalyst layer (CL) at the beginning‐of‐life (BOL) are characterized in terms of their initial size and shape, and their propagation is tracked as the CCMs are aged in a non‐reactive environment. The defected area in one of the commercial CCMs increases from approximately 2.4% of the total CL area at BOL to 10.5% by end‐of‐life (EOL). BOL defects in the CL are found to propagate faster in the CCMs stored for 2 years under atmospheric conditions compared with freshly manufactured CCMs with narrow CL defects. Image analysis of another commercial CCM shows the presence of pores with diameters between 5 and 25 μm that comprise 52% of the total pore area in the CL. Other defects such as scratches and missing/empty catalyst areas are identified and characterized, providing a framework for quality control applications. Finally, the effect of defects on fuel cell performance is characterized by measurement of the open‐circuit voltage (OCV). These experiments show that CCMs with a large number of cracks in the CL exhibit a voltage loss of 2.55 mV/hr, whereas CCMs with thin/missing/empty CL defects show a loss of 1.12 mV/hr. [ABSTRACT FROM AUTHOR]

The breakage of tools in the process of machining by removal of chip in industrial machinery is an important issue to consider because of the costs that can be generated by a setback in production or damage in parts of the machine-tool. High temperatures are one of the main causes that contribute to the damage of the tools and this problem has been researched in multiple studies; however, the use of refrigerant has not been considered due to its inherent interference in the process. The contribution of this work is the development of a smart-sensor for the timely detection of rupture of the tool in the milling process including refrigerant, which is specially designed with the application of infrared thermography and processing of thermal matrix obtained instead of the pseudo-color as commonly used. The outcome of this experimentation shows that with the smart-sensor, the condition of the tool in dry conditions and with coolant was obtained. Also, the smart-sensor provides the heat curves, images represented in different color palettes, the thermogram, and the average of the thermograms obtained during the monitoring of the cutting process. [ABSTRACT FROM AUTHOR]

Dynamic infrared thermography (DIRT) has been used for the preoperative mapping of cutaneous perforators. This technique has shown a positive correlation with intraoperative findings. Our aim was to evaluate the accuracy of perforator mapping with DIRT and augmented reality using a portable projector. For this purpose, three volunteers had both of their anterolateral thighs assessed for the presence and location of cutaneous perforators using DIRT. The obtained image of these "hotspots" was projected back onto the thigh and the presence of Doppler signals within a 10-cm diameter from the midpoint between the lateral patella and the anterior superior iliac spine was assessed using a handheld Doppler device. Hotspots were identified in all six anterolateral thighs and were successfully projected onto the skin. The median number of perforators identified within the area of interest was 5 (range, 3-8) and the median time needed to identify them was 3.5 minutes (range, 3.3-4.0 minutes). Every hotspot was correlated to a Doppler sound signal. In conclusion, augmented reality can be a reliable method for transferring the location of perforators identified by DIRT onto the thigh, facilitating its assessment and yielding a reliable map of potential perforators for flap raising. [ABSTRACT FROM AUTHOR]

The combinations of infrared thermal images and artificial intelligence methods have opened new avenues for pushing the boundaries of available testing methods. Hence, in the current study, a novel thermal non-destructive testing method for polyethylene electrofusion joints was combined with k-means clustering algorithms as an intelligent screening tool. The experiments focused on ovality of pipes in the coupler, as well as misalignment of pipes-couplers in 25 mm diameter joints. The temperature responses of each joint to an internal heat pulse were recorded by an IR thermal camera, and further processed to identify the faulty joints. The results represented clustering accuracy of 92%, as well as more than 90% abnormality detection capabilities. [ABSTRACT FROM AUTHOR]

In this paper, a new method based on the use of infrared thermography is proposed for the characterization of repairs and inserted parts on ancient bronzes. In particular, the quality of the contact between different kind of insertions and the main body of bronze statues is investigated by analysing the heat conduction process occurring across the interface between them. The thermographic results have been used to establish the nature of these inserted elements and the way they have been coupled to the main body of the statue during and after the manufacturing process. A model for the heat conduction based on the numerical finite elements method has been applied to compare the obtained results to the theoretical predictions. Measurements have been first carried out on test samples and then in the field on the Boxer at Rest ( Museo Nazionale Romano in Rome), a masterpiece of the Greek Statuary, which contains a large variety of inserted items and repairs which are typical of the manufacturing process of bronze artefacts in general. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the heat transfer processes during the freeze-drying of gelatin model solutions (GMS) with ethanol and carrier agents, and to understand the relation of the temperature profiles with gel thermorheological behaviors and microstructural properties of the freeze-dried systems. Temperature variations caused by phase transitions were detected using an infrared thermograph camera. Temperature profiles have shown that in systems of GMS that use ethanol with or without sucrose, water removal has occurred more rapidly and at lower temperatures. The activation energies determined were reduced with the addition of sucrose. Shrinkage measurements and photomicrographs allowed visualization of the cavities left after the sublimation of the ice and showed the additive effects on the water removal rate. The lowest shrinkage values were obtained for GMS using ethanol with or without sucrose, and the highest shrinkage values were obtained for GMS using maltodextrin, which presented amorphous structures. [ABSTRACT FROM AUTHOR]

In this work, glass/epoxy has been chosen as case study as it represents the most-used composite material, being appropriate for a vast variety of applications and a reasonable performance/cost compromise. This material has already been inline impact-monitored with infrared thermography, mostly for feasibility tests. Now, impact tests are repeated by changing some parameters and by inline monitoring simultaneously with two different infrared cameras to share a high frame rate and spatial resolution at the same time. In addition, glass/epoxy is monitored also while it is under quasi-static bending tests. The aim of this paper is to show what it is possible to learn from thermal signatures developing in the same material when it is either impacted or under quasi-static bending. [ABSTRACT FROM AUTHOR]

Abstract: In this work, high‐speed thermography is shown to effectively capture quasi‐stationary temperature fields during the laser welding of steel plates. This capability is demonstrated for two cases, with one involving the addition of a ferritic‐bainitic filler wire, and the other involving the addition of a low‐transformation‐temperature (LTT) filler wire. The same welding parameters are used in each case, but the temperature fields differ, with the spacing between isotherms being greater in the case where the low‐transformation‐temperature filler material is added. This observation is consistent with the differences in the extent of the heat‐affected zone in each sample, and the shape of the weld pool ripples on the weld bead surfaces. The characterization of temperature fields in this way can greatly assist in the development of novel methods for reducing residual stresses, such as the application of low‐transformation‐temperature filler materials through partial‐metallurgical injection (PMI). This technique reduces or eliminates tensile residual stresses by controlling the temperature fields so that phase transformations take place at the optimum times, and success can only be guaranteed through precise knowledge of the temperature fields in the vicinity of the welding heat source in real time. [ABSTRACT FROM AUTHOR]

In Neutral Beam Heated plasmas, Beam transmission must be carefully evaluated in plasma experiments involving NBI parameter scans. In the TJ-II stellarator a number of experiments have been carried out in which the beam energy (Vaccel) is changed at constant current (Iaccel), or vice versa. The beam transmission varies along the parameter scan according to the perveance value that determines the beam divergence. The transmission is calculated using a beam simulation code in which the beam geometry and divergence as well as the transmission apertures are included in a 3D model. In TJ-II Infrared thermography of the target calorimeter intercepting the beam is used in the divergence measurements. From the performed parameter scan it is concluded that neither the beam power nor the beam current injected in the plasma have a monotonic variation with the control parameters at the ion source (Vaccel or Iaccel). [ABSTRACT FROM AUTHOR]

The paper presents an experimental study on the floor heave of roadway excavated in deep ten degree inclined strata. During the processes of roadway floor heave, infrared thermography and video camera were employed for capturing the thermal response and displacement of roadway’s section, meanwhile, strain gauges installed with a circular layout in surrounding rocks was used for measuring roadway sectional deformation. Floor heave and failure was investigated by the combined analyses of the acquired infrared images, video photographs and straining field variations. A numerical model was also implemented based on the physical model for verifying the tunnel displacements obtained by image analysis of the photographs. The results showed that the horizontal stress had a great effect on the floor heave failure and the rock mass failure was accompanied with abnormal temperature change. [ABSTRACT FROM AUTHOR]

The paper aims to illustrate the relevant use of infrared thermography and energy based approaches to study the plastic behavior and the crack initiation under plain fretting loadings. A well known 35Ni Cr Mo 16 low-alloyed steel was studied under various plain fretting partial slip conditions. The experimental results showed that the proposed 2D image processing method is able to estimate thermoelastic amplitude fields in a good agreement with the theory of linear thermoelasticity, and mean intrinsic dissipation per cycle fields reflecting localized microplastic deformation. The maximal local evolution of the intrinsic dissipation as function of the shear stress amplitude, underlined the presence of a non-dissipative regime, where the specimen mainly undergoes elastic deformation and a dissipative regime where plastic deformation take place. The transition between these two regimes was then coupled with the local elastic shakedown boundary. [ABSTRACT FROM AUTHOR]

A key aspect in assessing the thermal standard of building envelopes is the quantification of the heat loss though thermal bridging, which can be expressed in terms of the linear thermal transmittance Ψ . Values of Ψ may be obtained from tabulated values for standard building details, from numerical modelling or from measurement. Where the internal structure of the building envelope is unknown, which is very often the case, measurement is the only option. This study shows how the infrared thermography technique (ITT) can be used as a non-invasive and easy-to-use method to provide quantitative measures of the actual thermal bridging performance. The novelty of this approach includes evaluation of the actual heat flow rate caused by thermal bridge q TB and Ψ -value by means of the ITT solely, without any supporting methods. Another important aspect of the methodology is that it accounts for the correlation between the surface temperature and the convective and radiative heat transfer coefficients. Values for these coefficients are assessed for the whole range of the surface temperatures recorded on the thermogram resulting in improve accuracy. The q TB and Ψ -value calculated using the presented methodology fully mirrors the real thermal performance of the thermal bridge. The methodology has been tested under laboratory conditions in a steady state in a hot box with excellent agreement. [ABSTRACT FROM AUTHOR]

The recovery of the true temperature of a metal powder during selective laser melting is examined. A method is proposed for determining the temperature of the surface of the melt bath of a metal powder during selective laser melting based on measurements with an infrared camera. The influence of key melt parameters on the geometry of the melt bath is estimated. [ABSTRACT FROM AUTHOR]

This retrospective study aimed to evaluate the differences in abdominal temperature (AT) between fertile (n=206; age) and infertile (n=250) women between the ages of 30 and 39 years. We evaluated the differences in two distinctive skin temperatures by thermography: Δ T 1 (CV8 index) – difference in temperature between the mid-abdomen (CV8 acupuncture area) and ventral upper arm (VUA) and Δ T 2 (CV4 index) – difference in temperature between the lower abdomen (CV4 acupuncture area) and VUA. The results indicated that the Δ T 1 and Δ T 2 of infertile women were significantly lower (by 1.05 °C and 0.79 °C, respectively; p<0.001, both) compared to those of fertile women. Additionally, the area under the curve of Δ T 1 (0.78) was greater compared to that of Δ T 2 (0.736), and its threshold was set at 0.675 °C, by which, the sensitivity and specificity of Δ T 1 for determination of fertility were found to be 80.8% and 68.4%, respectively. In conclusion, infertility is associated with lower AT. The decrease in AT in infertile women might be due to poor blood perfusion to the core muscles and tissues of the body. These findings provide a basis for further research for evaluation of clinical feasibility of thermography for analysis of infertility in women. Further evaluation of the influence of AT on fertility outcomes is required to determine the causal relationship between AT and infertility. [ABSTRACT FROM AUTHOR]

Infrared thermography is a technology that detects infrared radiation by thermographic cameras showing the surface temperature of the bodies, making it visible to our eyes, and allowing the visualization of fundamental physical and chemical principles, which otherwise would be impossible for our eyes. [ABSTRACT FROM AUTHOR]

The authors discuss the physiological bases of thermographic research and review its current applications in sport performance diagnostics on the basis of available professional literature. The methodology of thermographic studies involves the proper preparation of the workstation, thermographic equipment, and the athlete. The authors also refer to the results of their own research conducted during real training sessions. Factors influencing the obtained outcomes are discussed. [ABSTRACT FROM AUTHOR]

Phase change materials (PCM) are widely used today in thermal energy storage applications. Pure PCMs are rarely used because of non adapted melting points. Instead of them, mixtures are preferred. The search of suitable mixtures, preferably eutectics, is often a tedious and time consuming task which requires the determination of phase diagrams. In order to accelerate this screening step, a new method for estimating phase diagrams in record time (1–3 h) has been established and validated. A sample composed by small droplets of mixtures with different compositions (as many as necessary to have a good coverage of the phase diagram) deposited on a flat substrate is first prepared and cooled down to ambient temperature so that all droplets crystallize. The plate is then heated at constant heating rate up to a sufficiently high temperature for melting all the small crystals. The heating process is imaged by using an infrared camera. An appropriate method based on singular values decomposition technique has been developed to analyze the recorded images and to determine the transition lines of the phase diagram. The method has been applied to determine several simple eutectic phase diagrams and the reached results have been validated by comparison with the phase diagrams obtained by Differential Scanning Calorimeter measurements and by thermodynamic modelling. [ABSTRACT FROM AUTHOR]

Infrared thermography is a powerful non contact method with the ability to fast inspection of abnormal situations in many electrical systems and equipments. With the aim of a high resolution thermal camera a laboratory power transformer was checked under different scenarios. These scenarios include thermal measurements for 58%, 87% and 116% of rated load conditions, problems in primary or secondary phases and an asymmetric charge. The thermograpic system illustrate fast and reliable the changes in the windings of the power transformer. [ABSTRACT FROM AUTHOR]

Infrared thermography, thanks to its non-contact character, can be advantageously exploited to get information in lots of temperature-dependent applications. Indeed, a vast variety of infrared imaging devices is today available, allowing measurements also in complex configurations such as in presence of fast phenomena, or moving objects. Of course, the measurement accuracy depends strongly on the magnitude of temperature differences both in space and in time; some limitations may arise when attempting to measure temperature variations which are very small and at the edge of the instrument resolution. In this regard, a difficult task is to perceive the temperature variations which are related to thermo-elastic effects, e.g., developing under relatively low loads. The purpose of this work is to deepen inside the parameters that mostly affect such critical measurements and to search for a simple and reliable solution. Measurements are performed with the LWIR QWIP SC6000 camera and the obtained data are compared with those supplied by either an InSb MWIR camera, or an un-cooled camera. Particular attention is deserved to the electronic output of the infrared imaging device and to post-processing signal procedures. It is found that, through the use of a reference area, is possible to account and avoid most of the existing noise. [ABSTRACT FROM AUTHOR]

The angle of view between inspected object and thermal imager influences the values of temperature measured by infrared thermography. This happens because the emissivity depends on the angle of radiation, and because the apparent temperature measured is influenced by that angle of view combined to thermal imager’s field of view. Therefore, it is necessary to know the angle of view during thermographic inspection, which is generally not feasible due to safety reasons. This paper develops a method of measuring the angle of view with no contact with the inspected object, by employing laser distance meters, commonly available in the market. [ABSTRACT FROM AUTHOR]

The application of resonant magnetic perturbations (RMPs) produces splitting of the divertor strike point due to the interaction of the RMP field and the plasma field. The application of a rotating RMP field causes the strike point splitting to rotate, distributing the particle and heat flux evenly over the divertor. The RMP coils in MAST have been used to generate a rotating perturbation with a toroidal mode number n = 3. The ELM frequency is doubled with the application of the RMP rotating field, whilst maintaining the H mode. During mitigation, the ELM peak heat flux is seen to be reduced by 50% for a halving in the ELM energy and motion of the strike point, consistent with the rotation of the applied RMP field, is seen using high spatial resolution (1.5 mm at the target) heat flux profiles measured using infrared (IR) thermography. [ABSTRACT FROM AUTHOR]

This paper presents an experimental device developed to detect and estimate dissipated energy during very high cycle fatigue tests (VHCF) at high loading frequency (20 kHz) and low stress (i.e. far below the yield stress). Intrinsic dissipation is computed using local expressions of the heat diffusion equation and thermal data fields provided by an infrared focal plane array camera. The results obtained from tests performed on pure copper specimens show that dissipated energy exists whatever the attainable stress range and show that the dissipated energy rate is not constant throughout the test. Both findings are respectively incompatible with the concepts of fatigue limit based on elastic shakedown or on stabilized cyclic state associated with the mechanical hysteresis loop (viscoplastic shakedown). [ABSTRACT FROM AUTHOR]

Infrared thermography is a useful imaging technique for analyzing the thermomechanical behaviour of materials. It allows, under certain conditions, surface temperature monitoring and, via a diffusion model, estimation of heat sources induced by dissipative and/or thermally coupled deformation mechanisms. However, the noisy and discrete character of thermal data, the regularizing effect of heat diffusion and heat exchanges with the surroundings complicate the passage from temperature to heat source. The aim of this paper is to show that the prior use of reduced-basis projection of thermal data improves the signal-to-noise ratio before estimating the heat source distributions. The reduced basis is generated by proper orthogonal decomposition (POD) of physically-admissible thermal fields. These fields are solutions of ideal diffusion problems related to a set of putative heat sources. preprocessing is applied to different direct methods (finite differences, spectral solution, local least-squares fitting) already used in the past. The gain of this preprocessing is determined using a numerical penalizing benchmark test. The methods are finally compared using data extracted from a dynamic cyclic test on a pure copper specimen. [ABSTRACT FROM AUTHOR]

This paper is a combined numerical and experimental study which aims to demonstrate the implementation of the infrared thermography (IRT) method for the non-destructive evaluation of concrete masonry structural components. Specifically, a three-dimensional finite element (FE) analysis is formulated and implemented to predict both steady state and transient heat transfer in masonry specimens. A micro-element approach is followed to build the FE model geometry of the masonry walls. The model provides surface temperature contours which are the prime interest of infrared thermography. Three different scaled masonry specimens with identical thermal properties are considered for this study. The FE simulation results of heat diffusion are initially compared with finite difference method predictions for one specimen. Subsequently, the FE results are validated by implementing experimentally the IRT method on the other two specimens. The numerically predicted temperature values agree well with the actual measured values which validate the use of the IRT method for the nondestructive evaluation of concrete masonry components. [ABSTRACT FROM AUTHOR]

Adult–infant interactions operate simultaneously across multiple domains and at multiple levels – from physiology to behaviour. Unpackaging and understanding them, therefore, involve analysis of multiple data streams. In this study, we tested physiological responses and cognitive preferences for infant and adult faces in adult females and males. Infrared thermography was used to assess facial temperature changes as a measure of emotional valence, and we used a behavioural rating system to assess adults' expressed preferences. We found greater physiological activation in response to infant stimuli in females than males. As for cognitive preferences, we found greater responses to adult stimuli than to infant stimuli, both in males and females. The results are discussed in light of the Life History Theory. Finally, we discuss the importance of integrating the two data streams on our conclusions. [ABSTRACT FROM PUBLISHER]

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Infrared thermography (IRT) has met an extensive popularity among the non-destructive technologies for building diagnostics, especially with the increasing concerns of energy minimisation and low energy consumption of the building sector. Its popularity for a broad range of applications can be attributed to its non-contact safe nature, its usefulness and effectiveness, as well as the energy and cost savings it can achieve. This paper reviews the state-of-the-art literature and research regarding the passive and active infrared thermography. The fundamentals of IRT are thoroughly explained and the thermographic process for building diagnostics is presented. This work also presents the fields of applicability of IRT with a focus on the building sector, as well as the advantages, limitations and potential sources of errors of IRT employment. Additionally previous non-destructive testing (NDT) studies that employed passive, active pulsed, and active lock-in thermographies for building diagnostics are presented. A review of the thermal image analysis methods and the future trends of thermal imaging are also included in this work. It can be concluded that while IRT is a useful tool for the characterisation of defects in the building sector, there is great prospect for the development of more advanced, effective and accurate approaches that will employ a combination of thermography approaches. [ABSTRACT FROM AUTHOR]

Infrared thermography is a non-contact and full field inspection method which has proven to be suitable for automatic surface crack detection. For automatic analysis of the inspection results, a high signal-to-noise ratio (SNR) is required. In this paper an alternative excitation method, using ultraviolet (UV) illumination, is presented and evaluated. Artificial surface defects, so-called notches, in a titanium plate are detected both in the weld seam and in the heat affected zone. Notches with a size from 80 μm in width and 250 μm in length are detected. The SNR using UV illumination is compared with that using flash lamp excitation. The results show that UV illumination using a mercury lamp is a good alternative as excitation source for thermography when detecting surface cracks. To validate the excitation method, results from real surface cracks are included. [ABSTRACT FROM AUTHOR]

Any loss of power in converters is dissipated as heat in the components of the circuit. The article presents a new approach to measuring heat dissipation in a bridge power converter with hard switches using infrared thermography. Parallel measurements by thermocouples have been carried out. The experimental results are compared and used from the both cases. The proposed approach can be used for various circuit implementations of the converters in a similar manner. [ABSTRACT FROM AUTHOR]

This study presents a NDT method using infrared thermography associated with a microwave excitation. The advantages of such stimulation lie in the volumic absorption of incoming waves which lead to a greater sounded depth. This method is applied to two types of samples. The first is a concrete slab reinforced with CFRP on which a bonding failure is inserted and the second is a wooden plate on which a metallic insert is placed on the back face. The device generating the microwaves is made of a commercial magnetron associated with a pyramidal horn antenna. An infrared camera is placed on the same side as the stimulated surface and thermograms are recorded at regular intervals. The whole assembly is placed in a protective room against high frequencies. The incident power density leads to heating of less than 1 °C of the surface of the samples. The thermograms show a higher temperature rise in front of the defect area. The non-uniformity of the beam, leads us to treat the thermograms with an algorithm of contrast. These first results show the interest of the microwave excitation to detect defects deeper than in the case of surface excitation. [ABSTRACT FROM AUTHOR]

Coupling an infrared ( IR) camera to a freeze dryer for on-line monitoring of freeze-drying cycles is described for the first time. Normally, product temperature is measured using a few invasive Pt-100 probes, resulting in poor spatial resolution. To overcome this, an IR camera was placed on a process-scale freeze dryer. Imaging took place every 120 s through a Germanium window comprising 30,000 measurement points obtained contact-free from −40°C to 25°C. Results are presented for an empty system, bulk drying of cheese slurry, and drying of 1 mL human serum in 150 vials. During freezing of the empty system, differences of more than 5°C were measured on the shelf. Adding a tray to the empty system, a difference of more than 8°C was observed. These temperature differences probably cause different ice structures affecting the drying speed during sublimation. A temperature difference of maximum 13°C was observed in bulk mode during sublimation. When drying in vials, differences of more than 10°C were observed. Gradually, the large temperature differences disappeared during secondary drying and products were transformed into uniformly dry cakes. The experimental data show that the IR camera is a highly versatile on-line monitoring tool for different kinds of freeze-drying processes. © 2014 European Union 103:2088-2097, 2014 [ABSTRACT FROM AUTHOR]

Evidence of head-body temperature differences are known for many species of medium- to large-sized reptiles, but are scanty for small lacertid lizards. In this study, we heated 48 individuals of P odarcis muralis (19 males and 29 females) in order to investigate their ability to achieve and maintain local temperature differences between body parts. Lizards were put into polystyrene boxes and heated with incandescent lamps. Temperatures were measured with both an infrared thermometer and an infrared camera at four different body points every 20 min for 2 h. We found a statistically significant thermal gradient from the tip of the nose, the coolest part of the body, to the trunk, the warmest area, whereas the head achieved an intermediate temperature. We therefore hypothesize that P . muralis is able to physiologically regulate the heat distribution across its body. P odarcis muralis is sexually dimorphic, but neither sex nor body size are associated with temperature differences between individuals. The two measurement devices used responded differently to insulating material and to living animals, possibly indicating that infrared camera is able to detect dermal heat, while infrared thermometer detects mainly epidermal heat. This study shows for the first time that P . muralis can achieve and maintain temperature differences between the head and the body. [ABSTRACT FROM AUTHOR]

Traditional high-stiffness metal plates for Vancouver B1 femur shaft fractures below the tip of a hip implant can cause stress shielding, bone resorption, and implant loosening. This is the first study to compare the biomechanics of a traditional metal plate versus a low-stiffness carbon fibre/epoxy composite plate for this injury. A total hip replacement was implanted in two previously validated intact artificial femurs. Femurs were fitted with either a metal or composite plate and had a 5 mm fracture gap created to simulate a Vancouver B1 shaft fracture. Femurs were cyclically loaded using 5 Hz at 7° of adduction with an average axial load of 800 N (range = 400–1200 N). Overall mechanical stiffnesses and femur and plate thermographic stresses were obtained. Femur/metal plate stiffness (698 N/mm) was only 12% higher than femur/composite plate stiffness (625 N/mm). The femur with the composite plate had 22.7% higher combined average stress compared to the femur with the metal plate, having specific differences of 29.5% (anterior view), 33.9% (posterior view), 1.0% (medial view), and 26.4% (lateral view). The composite plate itself had an average 21.1% reduction in stress compared to the metal plate. The composite plate reduced stress shielding, yet provided adequate stiffness. [ABSTRACT FROM AUTHOR]

We compared the daily rhythms of body core temperature and surface temperature in 10 Comisana ewes housed at thermoneutrality (25 °C) and in the cold (9 °C). Core temperature was measured with a rectal probe, whereas surface temperature (in the eye, forehead, and foot) was measured by infrared thermography, at 3 h intervals for 27 consecutive hours under each condition. We found a robust rhythm of core temperature, whose amplitude doubled from 0.2 °C at thermoneutrality to 0.4 °C in the cold. The surface temperatures were all lower than core temperature and exhibited weaker but significant daily rhythmicity. At thermoneutrality, foot temperature (an indicator of vasodilation in the service of heat loss) peaked 3 h before rectal temperature. Studies on other species are needed to clarify whether the latency between the peaks of the oscillations in foot and core temperature vary in a species-specific manner and are responsible for the generation of the core temperature rhythm. [ABSTRACT FROM AUTHOR]

Abstract: Alternative and more practical methods for plant water stress detection than stem water potential (ψ s) and stomatal conductance (g s) are needed when regulated deficit irrigation (RDI) strategies are applied. The aim of this experiment was to compare sap flow and canopy temperature (T c) measurements with more classical methods like ψ s or g s to predict the effect of deficit irrigation on fresh fruit weight in citrus trees. The experiment was performed during the summer of 2011 in a “Clementina de Nules” orchard undergoing RDI. Sap flow was determined by means of the compensation heat pulse method in well-watered and RDI trees. T c was measured continuously with infrared thermometers (IRTs) mounted over the canopies and also weekly with an infrared hand-operated thermographic camera taking frontal images of the sunlit side of tree crowns. Concurrently, ψ s and g s were also measured on all trees. Results showed that the evolution of the relative transpiration obtained with the sap flow sensors was in agreement with the plant water stress experienced. The values of T c obtained with the fixed IRTs, normalized by air temperature (T c − T a) were in general poorly related with ψ s and g s. However, when T c was obtained from thermal imaging, there was a good correlation with ψ s in days of relatively high water stress (i.e. when ψ s differences among treatments were >1.0MPa). The average fruit weight at harvest was significantly correlated with all the stress indicators, and the best correlation was that of thermographic T c followed by ψ s and g s. Overall, results showed that in citrus trees T c measurement obtained from thermal imaging is a good tool to predict the effect of water deficit on fresh fruit weight. [Copyright &y& Elsevier]

Abstract: Infrared thermography (IRT) can be used in remote recognition of potential weakening features of a rock cliff like shallow holes, high fracturing, moisture or material inhomogeneities, providing useful information for the corresponding rock mass geo-engineering characterization. A method aimed at such a recognition is proposed here together with its MATLAB implementation (IRTROCK package). It is based on the acquisition of a series of IRT images during the night-time cooling of a rock mass and on the search for possible anomalous thermal transients. The IRT alone is unable to completely characterize a rock mass; a meaningful interpretation of the results requires a geological on-contact survey or other on-contact or contactless techniques. Nevertheless, the results obtained in a portion of the cliff, where a detailed study with other techniques has been carried out, can be advantageously extended to the whole cliff. Moreover, the IRT measurements can be easily and safety repeated over time to evaluate possible changes that affect the studied rock mass. The effectiveness of the proposed approach has been verified in two test sites. [Copyright &y& Elsevier]

Infrared thermographs (IRTs) implemented according to standardized best practices have shown strong potential for detecting elevated body temperatures (EBT), which may be useful in clinical settings and during infectious disease epidemics. However, optimal IRT calibration methods have not been established and the clinical performance of these devices relative to the more common non-contact infrared thermometers (NCITs) remains unclear. In addition to confirming the findings of our preliminary analysis of clinical study results, the primary intent of this study was to compare methods for IRT calibration and identify best practices for assessing the performance of IRTs intended to detect EBT. A key secondary aim was to compare IRT clinical accuracy to that of NCITs. We performed a clinical thermographic imaging study of more than 1000 subjects, acquiring temperature data from several facial locations that, along with reference oral temperatures, were used to calibrate two IRT systems based on seven different regression methods. Oral temperatures imputed from facial data were used to evaluate IRT clinical accuracy based on metrics such as clinical bias ( Δ c b ), repeatability, root-mean-square difference, and sensitivity/specificity. We proposed several calibration approaches designed to account for the non-uniform data density across the temperature range and a constant offset approach tended to show better ability to detect EBT. As in our prior study, inner canthi or full-face maximum temperatures provided the highest clinical accuracy. With an optimal calibration approach, these methods achieved a Δ c b between ±0.03 °C with standard deviation ( σ Δ c b ) less than 0.3 °C, and sensitivity/specificity between 84% and 94%. Results of forehead-center measurements with NCITs or IRTs indicated reduced performance. An analysis of the complete clinical data set confirms the essential findings of our preliminary evaluation, with minor differences. Our findings provide novel insights into methods and metrics for the clinical accuracy assessment of IRTs. Furthermore, our results indicate that calibration approaches providing the highest clinical accuracy in the 37–38.5 °C range may be most effective for measuring EBT. While device performance depends on many factors, IRTs can provide superior performance to NCITs. [ABSTRACT FROM AUTHOR]

Pea (Pisum sativum L.) is an important leguminous plant worldwide, in which pests trigger significant damage every year. One of the most important pest is pea weevil (Bruchus pisorum, L) which causes covert damage in crops. In the present study, our aim was to obtain precise information pertaining to the extent and the nature of damage in pea caused by B. pisorum by means of non-invasive imaging methods. The infested pea samples were analysed by an infrared thermometer and a bioluminescence plant imaging system as well as a computer tomograph under laboratory conditions. The calculated weight of organic matter destroyed by the developing larvae was 36.46%. The changing of RGB (red, blue, green) codes obtained through thermal imaging and the CPS (counts per second) values originating from bioluminescence imaging in infested samples were statistically verifiable. According to our CT assay, the damage caused by B. pisorum changed the tissue density, volume and shape of the pea seeds by the end of the development of the pest. The results of thermal and bioluminescence imaging contribute to a better understanding of the internal chemical processes and the CT analysis helps to understand the alteration trends of the inner structure of seeds caused by this pest. [ABSTRACT FROM AUTHOR]