Measurement and Processing of Thermographic Data of Passing Persons for Epidemiological Purposes.

Non-contact temperature measurement of persons during an epidemic is the most preferred measurement option because of the safety of personnel and minimal possibility of spreading infection. The use of infrared (IR) sensors to monitor building entrances for infected persons has seen a major boom between 2020 and 2022 due to the COVID-19 epidemic, but with questionable results. This article does not deal with the precise determination of the temperature of an individual person but focuses on the possibility of using infrared cameras for monitoring the health of the population. The aim is to use large amounts of infrared data from many locations to provide information to epidemiologists so they can have better information about potential outbreaks. This paper focuses on the long-term monitoring of the temperature of passing persons inside public buildings and the search for the most appropriate tools for this purpose and is intended as the first step towards creating a useful tool for epidemiologists. As a classical approach, the identification of persons based on their characteristic temperature values over time throughout the day is used. These results are compared with the results of a method using artificial intelligence (AI) to evaluate temperature from simultaneously acquired infrared images. The advantages and disadvantages of both methods are discussed.

Outdoor Target Positioning Using Wii Remote IR Camera and Signal Modulation.

This paper investigates the use of the Wii remote IR (infrared) camera for outdoor target positioning. The Wii remote IR camera is widely used in various applications because of its capability of detection of up to four IR light sources with a fast frame rate (100 Hz) and a relatively low price. However, previous applications are limited to indoor uses due to the obvious reason of sunlight interference for outdoor applications. In this paper, a signal modulation technique is introduced, which enables the IR camera to look for a particular pattern encoded in an IR beacon. In this way, the IR camera can distinguish the IR beacon from the sunlight interference. The irradiance of the sunlight reflection is also analyzed to guarantee that the IR camera can detect the IR beacon even under extremely sunny weather conditions. As the Wii remote IR camera sensor is overloaded under an extremely bright condition that blocks the camera to see any light sources, we propose the use of a filter to dim the camera. Experimental results for outdoor tests are provided to validate the proposed methods.

Digitized Hand Skateboard Based on IR-Camera for Upper Limb Rehabilitation.

Abnormal upper limb function seriously impacts a patient's daily life. After receiving emergency treatment patient should receive function-rebuilding and recovery training. The objective of this study is to integrate IR-camera, an infrared emitter, with a conventional passive hand skateboard training device for conventional upper limb training and the training process is comprehensively recorded and analyzed. Patients participating in the occupational therapy have a binding band attached to hand skateboard on the table to guide the patient in moving the hand skateboard along the designated path to train the patient's upper limbs. Six people with normal upper limb function participated in the stability test. The device repeatability and test results were verified acceptable. Eight patients with abnormal upper limb function (their upper limb function was damaged due to stroke, MMSE > =27) were trained for 4 weeks. The patient scores in finishing rate and finishing time showed significant improvement. The paired T test results (satisfy p < 0.05 or p < 0.01) between wk-1 and wk-2 are significant. The paired T test results (satisfy p < 0.01) between wk-1 and wk-4 are extremely significant. The new IR-Camera system focuses continuously on the "Figure of eight" curve. The system is light weight and convenient for stroke in home use. The study applies IR-camera technology to the conventional hand skateboard for upper limb training. The experiments show that the hardware of the proposed device no longer delays in response and can result in obvious clinical advances. The proposed device is verified worthy of promotion.

Combustion Growth of NiFe Layered Double Hydroxide for Efficient and Durable Oxygen Evolution Reaction.

NiFe layered double hydroxide (LDH) with abundant heterostructures represents a state-of-the-art electrocatalyst for the alkaline oxygen evolution reaction (OER). Herein, NiFe LDH/Fe2O3 nanosheet arrays have been fabricated by facile combustion of corrosion-engineered NiFe foam (NFF). The in situ grown, self-supported electrocatalyst exhibited a low overpotential of 248 mV for the OER at 50 mA cm-2, a small Tafel slope of 31 mV dec-1, and excellent durability over 100 h under the industrial benchmarking 500 mA cm-2 current density. A balanced Ni and Fe composition under optimal corrosion and combustion contributed to the desirable electrochemical properties. Comprehensive ex-situ analyses and operando characterizations including Fourier-transformed alternating current voltammetry (FTACV) and in situ Raman demonstrate the beneficial role of modulated interfacial electron transfer, dynamic atomic structural transformation to NiOOH, and the high-valence active metal sites. This study provides a low-cost and easy-to-expand way to synthesize efficient and durable electrocatalysts.

Brno urban dataset: Winter extension.

This paper presents our latest extension of the Brno Urban Dataset (BUD), the Winter Extension (WE). The dataset contains data from commonly used sensors in the automotive industry, like four RGB and single IR cameras, three 3D LiDARs, differential RTK GNSS receiver with heading estimation, the IMU and FMCW radar. Data from all sensors are precisely timestamped for future offline interpretation and data fusion. The most significant gain of the dataset is the focus on the winter conditions in snow-covered environments. Only a few public datasets deal with these kinds of conditions. We recorded the dataset during February 2021 in Brno, Czechia, when fresh snow covers the entire city and the surrounding countryside. The dataset contains situations from the city center, suburbs, highways as well as the countryside. Overall, the new extension adds three hours of real-life traffic situations from the mid-size city to the existing 10 h of original records. Additionally, we provide the precalculated YOLO neural network object detection annotations for all five cameras for the entire old data and the new ones. The dataset is suitable for developing mapping and navigation algorithms as well as the collision and object detection pipelines. The entire dataset is available as open-source under the MIT license.

Freezing Tolerance Enhancement and Thermographic Observation of Whole Peach Trees Applied with Cellulose Nanocrystals under Realistic Spring Frost Conditions Using a Soil-Fruit-Daylit-System.

Due to recent abnormal weather caused by global warming, peach flowering has gradually accelerated, and spring frost damage caused by premature de-acclimation has increased. In this study, under a simulated spring frost environment using a Soil-Fruit-Daylit-System (SFDS) chamber, we investigated whether treatment with 2% cellulose nanocrystals (CNCs) could enhance the freezing tolerance of the flower buds from 2-year-old whole peach trees. Visual changes in the ice propagation were observed using an infrared camera at the same time. After the peach flower buds in the calyx red stage were placed in the SFDS chamber with a minimum temperature of -4 °C for ~20 h, the percentage of browning in the pistils and stamens was 57.0% in the control group and 14.1% in the group treated with 2% CNCs. During the first pink stage, the percentages of browning in the pistils and stamens in the control group and the group treated with 2% CNCs were 98.2% and 70.3%, respectively. However, when peach flower buds in the group treated with 2% CNCs were exposed to a -6 °C-targeted chamber, they could not mitigate frost injury. Almost all flower buds were damaged. Infrared thermal images showed that the first exotherm in the control group began at 2:33:03 am, whereas that of the group treated with 2% CNCs began at 3:01:33 am. The control started to express exothermic behavior at -4.2 °C, while the group treated with 2% CNCs started expressing exothermic behavior at -5.1 °C. Thus, treatment with 2% CNCs enhanced the freezing tolerance by -0.9 °C and delayed the first instance of exothermic behavior by ~28 min. These results indicate that treatment with 2% CNCs could mitigate the frost damage of peach flower buds in a frost environment of -5 °C.

On the Use of Infrared Thermography for Monitoring a Vial Freeze-Drying Process.

Monitoring a vial freeze-drying process without interfering with product dynamics is a challenging issue. This article presents a novel device constituted by an infrared camera designed to be placed inside the drying chamber, able to monitor the temperature of the vials, very close to that of the product inside. By this way it is possible to estimate the ending point of the primary drying, the heat transfer coefficient to the product (Kv), and the resistance of the dried product to vapor flux (Rp). Experiments were carried out in a pilot-scale freeze-dryer, processing 5% and 10% sucrose solutions at different values of shelf temperature and chamber pressure, using both thermocouples and the IR camera to track product dynamics. Results evidence that the measurements (of temperature) and the estimates (of the ending point of the main drying and of Kv and Rp) obtained using the 2 systems are very close, thus validating the IR camera as an effective process analytical technologies for the freeze-drying process. Besides, it was shown that the presence of the IR camera in the chamber is not responsible for any additional heating to the product and that monitored vials are representative of the majority of the vials of the batch.

Monitoring of the freezing stage in a freeze-drying process using IR thermography.

This paper presents a new Process Analytical Technology based on the use of an infrared camera and a mathematical model to estimate the ice crystal size distribution obtained at the end of the freezing stage of a vial freeze-drying process. Both empirical laws and first-principle based equations, already presented in the Literature, may be used to this purpose, if the temperature gradient in the frozen product and the freezing front rate are obtained from the analysis of the thermal images. The resistance of the dried product to vapor flux may be then calculated from the distribution of the ice crystal diameters, thus enabling the use of a one-dimensional model for process simulation and optimization. Freeze-drying of 5% and 10% w/w aqueous sucrose solutions, and of 5% w/w aqueous mannitol solutions, were considered as case study. The results were validated comparing the calculated diameters of the pores of the dried cake, corresponding to the ice crystal diameters, with the results experimentally obtained from the analysis of the SEM images, and comparing the values of drying duration and maximum product temperature calculated with the mathematical model with those measured experimentally. Results evidences the effectiveness of the proposed system for process monitoring.

Detection of Delamination with Various Width-to-depth Ratios in Concrete Bridge Deck Using Passive IRT: Limits and Applicability.

In bridge structures, concrete decks have a higher risk of damage than other components owing to the direct impact of traffic. This study aims to develop a comprehensive system for bridge inspection using passive infrared thermography (IRT). Experiments were conducted on a concrete specimen (assumed as the surface of the bridge deck) embedded artificial delaminations with different width-to-depth ratios (WTDRs). Both professional handheld IR camera (H-IRC) and a UAV mounted with an IR camera (UAV-IRC) were employed simultaneously to capture the surface temperature of the structure. The present work indicates that the passive IRT technique with an H-IRC can be used to detect delaminations located at depths of 4 cm or less from the structure surface if the WTDRs are not lesser than 1.9 for daytime and 2.5 for nighttime when testing on a sunny day. In addition, the larger the WTDR, the higher the temperature difference can be produced, thus delaminations could be observed more clearly. Furthermore, our study suggests that the concrete bridge deck inspection using passive IRT can produce appropriate results if the inspection is performed from 10:00 to 15:00 or from 19:30 to approximately 2:00 on a sunny day. Good agreement between the results obtained from tests using H-IRC and UAV-IRC was observed, which validates the application of UAV-IRC in real structure inspection.

Visualizing and studying frictional heating effects in reversed-phase liquid chromatography using infrared thermal imaging.

Column temperature control is a fundamental component of liquid chromatography experiments. However, it is typically monitored indirectly by tracking the temperature of an adjacent heating element that exchanges heat with the column in a controlled environment. The practice of not directly measuring the column temperature means that uncontrolled contributions of heat, such as frictional heating inside the column, can be overlooked. The present work describes the use of a high-resolution infrared thermal imaging camera to directly measure the column heat map during mobile phase flow. The approach was used to measure the longitudinal temperature gradient formed with three common mobile phases: water, methanol, and acetonitrile, in two 50 mm reversed-phase columns, a 1.7 µm particle-packed column and a polystyrene divinylbenzene monolith. In a close approximation to an adiabatic environment, the temperature gradients (ΔT) observed with the 1.7 µm particle column at a linear velocity of 5.8 mm/s were up to +16.6 and + 12.8 °C above an ambient temperature of 23 °C for water and acetonitrile, respectively. In the case of water, the measured temperature gradient values (ΔT) were within 1% difference of theoretically-calculated values and on average within 10% for acetonitrile. By contrast, the ΔT observed in the monolith was negligible. The elevated temperatures that are generated through friction in sub-2 µm particle columns may be particularly important to consider for the design of experiments that measure structural features of temperature-sensitive analytes, such as biomolecules. While frictional heating is one important application of the thermal imaging approach described, the technique can be used to provide a data-rich profile of heat exchange in numerous experimental configurations, chromatographic or otherwise.