Continuous Temperature Measurements Research Articles

Malt Barley Yield and Quality Response to Crop Water Stress Index

Malt barley is a crucial irrigated crop in the semi-arid Western United States, where the states of Idaho, Colorado, Wyoming, and Utah account for 92% of the irrigated production acreage and 30% of total U.S. production. In this region, spring malt barley’s seasonal evapotranspiration ranges from 400 to 650 mm, and competition for limited water supplies, coupled with drought, is straining regional water resources. This study aimed to investigate the use of canopy temperature for deficit irrigation scheduling of malt barley. Specifically, the objectives were to use data-driven models to estimate well-watered (TLL) and non-transpiring (TUL) canopy temperatures, correlate the crop water stress index (CWSI) with malt barley yield and quality measures, and assess the applicability of CWSI for malt barley irrigation scheduling in a semi-arid climate. A 3-year field study was conducted with five irrigation treatments relative to estimated crop evapotranspiration (full, 75%, 50%, 25%, and no irrigation) and four replicates each. Continuous canopy temperature measurements and meteorological data were collected, and a feedforward neural network model was used to predict TLL, while a physical model was used to estimate TUL. The neural network model accurately predicted TLL, with a strong correlation (R2 = 0.99), a root mean square error of 0.89 °C, and a mean absolute error of 0.70 °C. Significant differences in calculated season-average CWSI were observed between the irrigation treatments, and relative evapotranspiration, malt barley relative yield, test weight, and plump kernels were negatively correlated with the season-average CWSI, while seed protein was positively correlated. The relationship between daily CWSI and fraction of available soil water was well described by an exponential decay function (R2 = 0.72). These results demonstrate the applicability of data-driven models for computing CWSI of irrigated spring malt barley in a semi-arid environment and their ability to assess plant water stress and predict crop yield and quality response from CWSI.

Experimental investigation of a nano coating efficiency for dust mitigation on photovoltaic panels in harsh climatic conditions

Dust accumulation on photovoltaic (PV) panels in arid regions diminishes solar energy absorption and panel efficiency. In this study, the effectiveness of a self-cleaning nano-coating thin film is evaluated in reducing dust accumulation and improving PV Panel efficiency. Surface morphology and elemental analysis of the nano-coating and dust are conducted. Continuous measurements of solar irradiances and ambient temperature have been recorded. SEM analysis of dust revealed irregularly shaped micron-sized particles with potential adhesive properties, causing shading effects on the PV panel surface. Conversely, the coating particles exhibited a uniform, spherical shape, suggesting effective prevention of dust adhesion. Solar irradiance ranged from 120 W/m² to a peak of 720 W/m² at noon. Application of the self-cleaning nano-coating thin film consistently increased short circuit current (Isc), with the coated panel averaging 2.8 A, which is 64.7% higher than the uncoated panel’s 1.7 A. The power output of the coated panel ranged from 7 W to 38 W, with an average of approximately 24.75 W, whereas the uncoated panel exhibited a power output between 3 W and 23 W, averaging around 14 W. These findings highlight the substantial potential of nano-coating for effective dust mitigation, particularly in dusty environments, thus enhancing PV system reliability.

The interplay of temperature and circadian periodicity in winter activity of non-cavernous hibernator, Nyctalusnoctula

Winter activity of hibernating mammals is likely to be influenced by climate change. Our study focuses on Nyctalus noctula, a non-cavernous hibernator using artificial roosts in a recently colonized winter region. Using continuous acoustic monitoring and temperature measurements inside and outside the roosts, we found that bats exhibit a circadian cycle (active at night, resting during the day) even during hibernation season. Activity duration and intensity changed in response to ambient temperature, photoperiod, and hibernation progression. Warm ambient temperatures led to increased nighttime activity, extending the duration of the active phase. As photoperiod increased, the rest phase lengthened, while the overall magnitude of activity decreased from the beginning to the end of the hibernation period. Below 0 °C vocal activity was nearly zero indicating a minimal probability of bat activity during both day and night. The species recent success in extending its hibernation range northward may be attributed to its flexible adjustment to prevailing environmental conditions. Nevertheless, it remains uncertain whether engaging in daily activity at temperatures above 0 °C confers any advantages at northern latitudes to prevent premature energy depletion. The persistence of circadian activity during winter could be a relic behavior, adapted from historical patterns of wintering in insect-rich and warm southern latitudes.

Fracture Characterization Via AI‐Assisted Analysis of Temperature Logs

AbstractFractures control fluid flow, mass transport, and heat transfer in a geothermal reservoir. This makes accurate characterization of fracture networks a prerequisite for optimal design and control of a reservoir's exploitation. We develop a deep‐learning procedure to identify fracture locations via interpretation of temporally and spatially continuous downhole temperature measurements. A long short‐term memory fully convolutional network (LSTM‐FCN) is used both to capture long‐term dependencies in sequential temperature data and to distill local features around fractures. A wellbore and fractured‐reservoir thermal model is established to generate temperature data for network training. The trained LSTM‐FCN exhibits a unique ability to detect multiple fractures intersecting a borehole. We use the LSTM‐FCN algorithm to evaluate the effectiveness of different‐stage wellbore temperature measurements on fracture detection in a complex fractured system. Our experiments reveal that the use of various‐stage temperature information as an input feature set improves the robustness of fracture detection to noise interference. This study indicates the practical feasibility of obtaining accurate fracture‐network reconstructions from temperature signals, at reasonable computational cost.

Stratification and respiration dynamics in shallow ponds: insights from continuous temperature measurements

Stratification and respiration dynamics in shallow ponds: insights from continuous temperature measurements

Thermal Behaviour of Cool-Pavement Materials Development using Palm Oil Shell Aggregate

Cool-pavement technology has emerged as a potential solution to environmental issues posed by the urban heat island phenomenon, with surface temperature acting as a vital parameter in the evaluation of its thermal performance. This study focuses on the thermal performance results of modified asphalt concrete mix, wherein palm oil shell (POS) serves as a replacement for fine aggregate. Modified asphalt samples prepared using the Marshall Mix Design, with varying degrees of fine aggregate substitution (0%, 10%, 20%, 30%, 40%, and 50%), underwent a 24-hour continuous surface temperature measurement over a span of 20 days, under real-world tropical climate conditions. The findings demonstrated that sample P5, comprising 50% fine aggregate substitution, exhibited the highest reduction in surface temperature when compared to control sample P0, registering a significant decrease of up to 3.29°C during the period of peak solar intensity. ANOVA test-based statistical analyses confirmed significantly lower temperatures for all test samples, barring sample P1 (10% aggregate replacement), relative to the control sample. The results highlight the efficacy of POS as a fine aggregate substitute in asphalt concrete, significantly lowering asphalt pavement surface temperature, thereby endorsing the potential use of POS-modified asphalt in cool-pavement applications.

Recent Advances in Flexible Temperature Sensors: Materials, Mechanism, Fabrication, and Applications.

Flexible electronics is an emerging and cutting-edge technology which is considered as the building blocks of the next generation micro-nano electronics. Flexible electronics integrate both active and passive functions in devices, driving rapid developments in healthcare, the Internet of Things (IoT), and industrial fields. Among them, flexible temperature sensors, which can be directly attached to human skin or curved surfaces of objects for continuous and stable temperature measurement, have attracted much attention for applications in disease prediction, health monitoring, robotic signal sensing, and curved surface temperature measurement. Preparing flexible temperature sensors with high sensitivity, fast response, wide temperature measurement interval, high flexibility, stretchability, low cost, high reliability, and stability has become a research target. This article reviewed the latest development of flexible temperature sensors and mainly discusses the sensitive materials, working mechanism, preparation process, and the applications of flexible temperature sensors. Finally, conclusions based on the latest developments, and the challenges and prospects for research in this field are presented.

Comparison of continuous temperature measurement methods in the intensive care unit: standard bladder catheter measurements versus non-invasive transcutaneous sensors.

The purpose of this study was to compare a wearable system for body core temperature measurement versus bladder and tympanic thermometers in an intensive care setting. The question was, if continuous non-invasive sensors in the intensive care unit represent an alternative to current standard methods of invasive continuous bladder temperature measurement methods?Between May and September 2023, a comparative investigation involving 112 patients was conducted in a 20-bed surgical intensive care unit to assess various temperature probes, including those placed in the tympanic tube, bladder, and skin. To achieve this, a wireless non-invasive sensor system provided by greenTEG AG, Switzerland, was affixed to different body locations (clavicular and lateral chest) of each catheterized patient (equipped with a temperature probe) admitted to the intensive care unit. Furthermore, tympanic temperatures were recorded at specified intervals. The measurement duration ranged from a minimum of six hours to a maximum of six days, resulting in the analysis of a total of 355 simultaneous temperature measurements.In this study, a wearable temperature measurement system attached to two different body sites revealed a consistent negative bias compared to bladder temperature. In addition, the measurements were particularly influenced by body constitution. The tested system in all patients showed a mean absolute error (MAE) of 0.45°C for the lateral chest and 0.50°C for the clavicular position. Tympanic measurements had a mean absolute error of 0.35°C. In patients with body mass index (BMI) ≥ 25 the MAE increased to 0.5°C for the lateral chest and 0.56°C for the clavicular position. In contrast, the tympanic measurement had a reduced MAE of 0.32°C, which is well below this threshold when compared to bladder measurements.In conclusion the investigated system did not meet the clinically relevant acceptance criteria and showed low precision in correctly identifying fever episodes compared to invasive temperature probes, however its main advantage lies in its continuity and non-invasiveness. This makes it a potential alternative to intermittent tympanic measurement devices. In this study we were able to show, that in at least one subset of patients, the non-invasive and continuous device demonstrated a precision comparable to tympanic measurements.The accuracy of all non-invasive methods was lower than in previous studies, suggesting that the use of bladder temperature as reference and user related variations may have introduced additional errors.

Comparison of Wireless Continuous Axillary and Core Temperature Measurement after Major Surgery.

Temperature is considered one of the primary vital signs for detection of complications such as infections. Continuous wireless real-time axillary temperature monitoring is technologically feasible at the general ward, but no clinical validation studies exist. This study compared axillary temperature with a urinary bladder thermometer in 40 major abdominal postoperative patients. The primary outcome was changes in axillary temperature registrations. Secondary outcomes were mean bias between the urinary bladder and the axillary temperatures. Intermittent frontal and tympanic temperature recordings were also collected. Forty patients were monitored for 50 min with an average core temperature of 36.8 °C. The mean bias was -1.0 °C (LoA -1.9 to -0) after 5 min, and -0.8 °C (LoA -1.6 to -0.1) after 10 min when comparing the axillary temperature with the urinary bladder temperature. After 20 min, the mean bias was -0.6 °C (LoA -1.3-0.1). During upper arm abduction, the axilla temperature was reduced to -1.6 °C (LoA -2.9 to -0.3) within 1 min. Temporal skin temperature measurement had a resulted in a mean bias of -0.1 °C (LOA -1.1 to -1.0) compared with central temperature. Compared with the mean tympanic temperature, it was -0.1 °C (LoA -0.9 to -1.0) lower than the urinay bladder temperature. Axillary temperature increased with time, reaching a mean bias of 1 °C between axillary and core temperature within 5 min. Opening the axillary resulted in rapidly lower temperature recordings. These findings may aid in use and designing corrections for continuous axillary temperature monitoring.

Development of a micro-infrared thermometry method for surface temperature distribution and variation of millimeter particle during high-temperature reaction

Temperature strongly affects the conversion efficiency, local reactivity, and particle stabilization of the reactions, particularly at high temperature. This study integrated infrared thermography with a high-temperature hot stage reactor to develop a methodology of continuous temperature measurement for a single particle reaction at high temperatures. The external optical transmission transmittance and temperature field core were corrected, and the relationship between the measured temperature (Tr) and true temperature (T0) was obtained by adjusting the sample emissivity. Sample temperature with known emissivity at elevated temperature was measured with 1% deviation. The instantaneous temperature measurement for the gasification process was carried out and the overall emissivities of coal particles were corrected. Temperature distribution and variation on the coal particle surface during the gasification process were further obtained and consistent with the previous research results. The proposed online temperature measurement method provides a new approach for gaining insights into particle reaction states.

Freshwater discharge drives latitudinal changes of phytoplankton composition on the continental shelf off Chilean Patagonia

A high-resolution survey of distribution, abundance and composition of phytoplankton was carried out for the first time in surface waters of the continental shelf off Chilean Patagonia (41–48°S). An Imaging FlowCytobot was used along the survey track to record phytoplankton in the size range of 10–120 μm during the austral spring of 2018. Phytoplankton community structure was complemented with continuous underway measurements of temperature and salinity, and physicochemical parameters of the water column at 35 oceanographic stations. Our results evidenced two main macrozones with distinctive phytoplankton assemblages delimited latitudinally at ~45°S. The northern macrozone was characterized by higher surface temperature and salinity, Si:N ratio > 1, diatoms of the genera Thalassiosira and Chaetoceros, and dinoflagellates accounting for over 70% of the total abundance. The southern macrozone, with lower surface temperature and salinity and Si:N ratio < 1, was characterized by members of the genera Guinardia, Lauderia and Cerataulina, representing over 60% of the total phytoplankton. These changes were attributable to the strong influence of freshwater at latitudes higher than 45°S and the enhanced discharge of meltwaters from Patagonian icefields in the area of the Taitao Peninsula and the Gulf of Penas (47–-48°S). Fresh and cold waters impacted the water column stratification and the availability of dissolved silicic acid with potential effects on phytoplankton composition and diatom cell silicification and, thus, on carbon exportation. Our estimations of phytoplankton carbon were comparable to those observed in Patagonian fjords and the highly productive upwelling ecosystem of central Chile. We suggest that the continental shelf off Patagonia can contribute significantly to strengthen the biological carbon pump through the synthesis, exportation, and sequestration of phytoplankton-based organic carbon in the southeastern Pacific Ocean.

Evaluation and Correction of PurpleAir Temperature and Relative Humidity Measurements

The PurpleAir PA-II sensor provides low-cost in situ measurements of meteorological variables including temperature and relative humidity (RH), as well as fine particulate matter (PM2.5) in real time. The sensors have been used in several studies investigating intracity differences in temperature and PM2.5. While the adoption and use of low-cost sensors has many benefits, care must be taken to ensure proper calibration and testing. This is true not only for PM2.5 measurements but also for temperature and RH given the synergistic health impacts from extreme heat and air pollution exposure. Here, we compare continuous temperature and RH measurements from a PA-II sensor to measurements from a Campbell Scientific 107 temperature probe and Vaisala HMP45C RH probe. All three instruments were co-located from December 2021 to June 2023 in Asheville, North Carolina. We found that the PA-II has an overall high temperature bias of 2.6 °C and root mean square error (RMSE) of 2.8 °C. Applying a linear regression correction reduces RMSE to 1.0 °C, while applying the constant 4.4 °C correction suggested by PurpleAir reduces RMSE to only 2.2 °C. Our PA-II RH measurements have a low bias of −17.4% and uncorrected RMSE of 18.5%. A linear regression correction improves the RH RMSE to 4.5%. Applying the constant 4% RH correction suggested by PurpleAir reduces RMSE to only 14.8%. We present new correction factors that differ from those suggested by PurpleAir, which overcorrect the high temperature bias and undercorrect the low RH bias. We also show that our correction factors improve estimates of dewpoint temperature (RMSE of 0.6 °C and 0.9 °C) compared to the corrections suggested by PurpleAir.

Интенсивность нейтронной компоненты космических лучей и влажность воздуха

Neutron monitor data is currently corrected only for the barometric effect. We cannot, however, exclude that changes in air humidity affect the intensity of the cosmic-ray neutron component recorded by neutron monitors. In this regard, we have carried out continuous measurements of air humidity and temperature when observing variations in the cosmic ray intensity with a neutron monitor in Novosibirsk. Analysis of the results of observations of meteorological parameters and cosmic ray intensity in Novosibirsk, as well as data from the global network of neutron monitors, made it possible to identify neutron component intensity variations caused by changes in air humidity. The estimated humidity effect indicates the need to regularly take it into account in the neutron monitor data. To do this, along with atmospheric pressure, regular measurements of humidity and air temperature should be performed.

Intensity of the neutron component of cosmic rays and air humidity

Neutron monitor data is currently corrected only for the barometric effect. We cannot, however, exclude that changes in air humidity affect the intensity of the cosmic-ray neutron component recorded by neutron monitors. In this regard, we have carried out continuous measurements of air humidity and temperature when observing variations in the cosmic ray intensity with a neutron monitor in Novosibirsk. Analysis of the results of observations of meteorological parameters and cosmic ray intensity in Novosibirsk, as well as data from the global network of neutron monitors, made it possible to identify neutron component intensity variations caused by changes in air humidity. The estimated humidity effect indicates the need to regularly take it into account in the neutron monitor data. To do this, along with atmospheric pressure, regular measurements of humidity and air temperature should be performed.

Phenotypes for general behavior, activity, and body temperature in 3q29 deletion model mice

Whole genome analysis has identified rare copy number variations (CNV) that are strongly involved in the pathogenesis of psychiatric disorders, and 3q29 deletion has been found to have the largest effect size. The 3q29 deletion mice model (3q29-del mice) has been established as a good pathological model for schizophrenia based on phenotypic analysis; however, circadian rhythm and sleep, which are also closely related to neuropsychiatric disorders, have not been investigated. In this study, our aims were to reevaluate the pathogenesis of 3q29-del by recreating model mice and analyzing their behavior and to identify novel new insights into the temporal activity and temperature fluctuations of the mouse model using a recently developed small implantable accelerometer chip, Nano-tag. We generated 3q29-del mice using genome editing technology and reevaluated common behavioral phenotypes. We next implanted Nano-tag in the abdominal cavity of mice for continuous measurements of long-time activity and body temperature. Our model mice exhibited weight loss similar to that of other mice reported previously. A general behavioral battery test in the model mice revealed phenotypes similar to those observed in mouse models of schizophrenia, including increased rearing frequency. Intraperitoneal implantation of Nano-tag, a miniature acceleration sensor, resulted in hypersensitive and rapid increases in the activity and body temperature of 3q29-del mice upon switching to lights-off condition. Similar to the 3q29-del mice reported previously, these mice are a promising model animals for schizophrenia. Successive quantitative analysis may provide results that could help in treating sleep disorders closely associated with neuropsychiatric disorders.

Accuracy of a zero-heat-flux thermometer in cardiac surgery, a prospective, multicentre, method comparison study

Accurate measurement of core temperature is of utmost importance during on-pump cardiac surgery, for detection of hypothermia before cardiopulmonary bypass (CPB), guidance of temperature management on CPB, active rewarming on CPB and guidance of warming therapy after CPB. Most temperature measurement methods are known to become inaccurate during rapid changes in core temperature and suffer from delayed detection of temperature changes. Zero-heat-flux temperature (ZHF) measurement from the lateral forehead may be an alternative, non-invasive method quantifying the core temperature. A prospective, observational, multicentre study was conducted in one hundred patients scheduled for on-pump coronary artery bypass grafting. Core temperatures were measured every minute by two zero-heat-flux thermometer (SpotOn™) and a bladder thermometer and a pulmonary artery catheter (PAC) in the period after induction of anesthesia until CPB. Accuracy and precision of both methods were compared against core temperature measured in the pulmonary artery using the method of Bland and Altman. A high accuracy (around 0.1 °C) and a very good precision (Limits of agreement (LoA) − 0.6; 0.4 °C) were found between zero-heat-flux thermometer and core temperature measured by PAC. Among the two ZHF thermometers the bias was negligible (− 0.003 °C) with narrow LoA of − 0.42 °C and 0.41 °C. In contrast, bias between bladder temperature and PAC temperature was large (0.51 °C) with corresponding LoA of − 0.06 °C and 1.1 °C. ZHF thermometers are in contrast to bladder temperature a reliable core temperature monitor in cardiac surgery during the period after induction of anestesia until CPB. The zero-heat-flux method can provide clinicians reliably with continuous and non-invasive measurements of core temperature in normothermic and mild hypothermic temperature ranges and therefore can be helpful to guide temperature management.

Integrating Fiber Sensing for Spatially Resolved Temperature Measurement in Fuel Cells

Fiber optic sensors integrated into fuel cell stacks have the potential to significantly enhance the temperature control and health monitoring of fuel cells. Inhomogeneous loading, both within individual cells and across different cells in a stack, leads to the formation of local hotspots that accelerate aging and degrade performance. This study investigates the behavior and feasibility of incorporating polyimide-coated optical fiber sensors into bipolar plates for precise and spatially resolved temperature monitoring. The sensor is successfully integrated into a single cell of a fuel cell stack, positioned on the bipolar plate in direct contact with the membrane. Pre-tests are conducted to thoroughly evaluate the technical properties of the fiber in relation to specific cell requirements. Additionally, a physical prototype featuring the sensor is developed and employed to validate its effectiveness under realistic operating conditions. The temperature measurement obtained via the fiber exhibits a continuous profile throughout the entire length, covering both the active area and distributor region of the cell. Throughout the entire 60 min test period, the measuring system provided continuous and uninterrupted temperature measurements, encompassing the start of the stack, the heating phase, the subsequent stable operating point, and the cooling phase. However, some technical challenges are identified, as mechanical pressure exerted on the fiber influences the measured temperature. While this work demonstrates promising results, further advancements are necessary to address inhomogeneous loading within fuel cells and hotspot mitigation. The precise monitoring of temperature distribution enables early detection of potential damage, facilitating timely interventions to improve the service life and overall performance of fuel cells.

Seasonal and spatial variability of CO2 emissions in a large tropical mangrove‐dominated delta

AbstractThis study quantified the seasonal and spatial variability of partial pressure of CO2 (pCO2) and water‐atmosphere CO2 fluxes in the Parnaíba River Delta, the largest delta in the Americas. It is a pristine equatorial, mangrove‐dominated environment located in a transitional between humid and semi‐arid climates, with marked seasonality in rainfall and river discharge. Major channels and bays were sampled during dry and wet seasons, with continuous measurements of pCO2, temperature, salinity, and wind velocity. Subsurface water samples were collected in discrete stations for pH, total alkalinity (TA), dissolved inorganic carbon (DIC), dissolved oxygen and chlorophyll a quantification. A significant positive correlation between carbonate system parameters with salinity was found in both periods, with salinity significantly higher in the dry season. Strong deviations of pCO2, TA, and DIC from two endmembers conservative mixing were found, particularly in mangrove‐dominated waters, due to organic matter degradation. The Delta showed high spatial variability of pCO2, with the highest values in mangrove‐dominated waters, moderate in the river‐dominated regions, and lowest in the high salinity areas, suggesting that pCO2 variability is likely controlled by a combination of river‐ocean mixing and biological processes (respiration and photosynthesis). The Delta outgasses about 20 times less CO2 in the dry season (9.06 ± 11.09 mmol m−2.d−1) than in the rainy season (209.68 ± 250.87 mmol m−2 d−1). Our results indicate this large mangrove‐dominated tropical delta is an important source of CO2 to the atmosphere, but a sharp decrease was observed during dry periods.

Comparing body temperature measurements using the double sensor method within a wearable device with oral and core body temperature measurements using medical grade thermometers-a short report.

Introduction: Body temperature is essential for diagnosing, managing, and following multiple medical conditions. There are several methods and devices to measure body temperature, but most do not allow continuous and prolonged measurement of body temperature. Noninvasive skin temperature sensor combined with a heat flux sensor, also known as the "double sensor" technique, is becoming a valuable and simple method for frequently monitoring body temperature. Methods: Body temperature measurements using the "double sensor" method in a wearable monitoring device were compared with oral and core body temperature measurements using medical grade thermometers, analyzing data from two prospective clinical trials of different clinical scenarios. One study included 45 hospitalized COVID-19 patients in which oral measurements were taken using a hand-held device, and the second included 18 post-cardiac surgery patients in which rectal measurements were taken using a rectal probe. Results: In study 1, Bland-Altman analysis showed a bias of -0.04°C [0.34-(-0.43)°C, 95% LOA] with a correlation of 99.4% (p < 0.001). In study 2, Bland-Altman analysis showed a bias of 0.0°C [0.27-(-0.28)°C, 95% LOA], and the correlation was 99.3% (p < 0.001). In both studies, stratifying patients based on BMI and skin tone showed high accordance in all sub-groups. Discussion: The wearable monitor showed high correlation with oral and core body temperature measurements in different clinical scenarios.

Accuracy of a Dual-Sensor Heat-Flux (DHF) Non-Invasive Core Temperature Sensor in Pediatric Patients Undergoing Surgery.

Accurate temperature measurement is crucial for the perioperative management of pediatric patients, and non-invasive thermometry is necessary when invasive methods are infeasible. A prospective observational study was conducted on 57 patients undergoing elective surgery. Temperatures were measured using a dual-sensor heat-flux (DHF) thermometer (Tcore™) and a rectal temperature probe (TRec), and the agreement between the two measurements was assessed. The DHF measurements showed a bias of +0.413 °C compared with those of the TRec. The limits of agreement were broader than the pre-defined ±0.5 °C range (-0.741 °C and +1.567 °C). Although the DHF sensors tended to overestimate the core temperature compared to the rectal measurements, an error grid analysis demonstrated that 95.81% of the DHF measurements would not have led to a wrong clinical decision, e.g., warming or cooling when not necessary. In conclusion, the low number of measurements that would have led to incorrect decisions suggests that the DHF sensor can be considered an option for continuous temperature measurement when more invasive methods are infeasible.