Thermometer Research Articles

Visual search for hazardous items: using virtual reality (VR) in laypersons to test wearable displays for firefighters

In virtual reality (VR), we assessed how untrained participants searched for fire sources with the digital twin of a novel augmented reality (AR) device: a firefighter’s helmet equipped with a heat sensor and an integrated display indicating the heat distribution in its field of view. This was compared to the digital twin of a current state-of-the-art device, a handheld thermal imaging camera. The study had three aims: (i) compare the novel device to the current standard, (ii) demonstrate the usefulness of VR for developing AR devices, (iii) investigate visual search in a complex, realistic task free of visual context. Users detected fire sources faster with the thermal camera than with the helmet display. Responses in target-present trials were faster than in target-absent trials for both devices. Fire localization after detection was numerically faster and more accurate, in particular in the horizontal plane, for the helmet display than for the thermal camera. Search was strongly biased to start on the left-hand side of each room, reminiscent of pseudoneglect in scene viewing. Our study exemplifies how VR can be used to study vision in realistic settings, to foster the development of AR devices, and to obtain results relevant to basic science and applications alike.

Comparison of coating damage and shape retention quantity of microcatheter by different shaping methods

ObjectiveTo compare the coating damage and shape retention quality of microcatheter by steam (ST), hot air gun (HA), and HA + ST shaping. MethodSL-10, XT-17, and Q-track microcatheters were included in the study. MarSurf CM explorer (a non-contact 3D confocal microscopy system) and MATLAB software were used to detect the surface coating damage. To detect the shape retention quantity, ImageJ software was used to analyze the images of the shaped microcatheters. Temperature of the outlet of the ST and HA was measured using a high precision contact digital thermometer. ResultsHA could reach the preset temperature (3 ∼ 4 s) 17 times faster than an ST (54 s). HA + ST produced relatively consistent heat flow output. HA had better shape retention quantity than ST, and HA + ST had a relatively better shape retention quantity compared with ST or HA alone. ST had a protective effect on the hydrophilic coating on the surface of microcatheter, and shaping by ST + HA could reduce the damage caused by HA to the surface coating. ConclusionsHA and ST had their own advantages in microcatheter shaping. HA had a better shape retention quantity than ST, and reached the setting temperature faster than ST. ST had the ability to better protect the coating than HA. A device capable of simultaneously generating efficient and stable heat flow and eliminating heat flow damage to the surface coating can be designed for ideal microcatheter shaping.

DETERMINATION OF CALIBRATION MEASUREMENT UNCERTAINTY EFFECT FOR DIFFERENT AMBIENT TEMPERATURES UPON DIGITAL THERMOMETER READOUTS

Calibration of digital thermometer is usually performed in laboratory environmental conditions, mostly at 23 degree Celsius Plus Minus 3 degree Celsius. However, after calibration, there may be circumstances where the device is used at different temperatures. Generally for on-site processes, it is not much possible to provide laboratory environmental conditions. In that situation, it is necessary to determine how the device responds to different temperatures. In this study, calibration measurement uncertainty effect for different ambient temperatures upon digital thermometer readout is investigated by exposing digital thermometer readout to temperature values of 10 degree Celsius and 40 degree Celsius.

Diphenylacetylene‐Incorporating Octaphyrin: A Rigid Macrocycle with Readily Separable Conformational Isomers

AbstractAn expanded carbaporphyrinoid analogue, octaphyrin(2,1,1,1,2,1,1,1), containing two rigid diphenylacetylene moieties is reported. In contrast to traditional pyrrolic macrocycles where flexible conformers coexist in dynamic equilibrium, this macrocycle exists as two separable, conformationally stable stereoisomers, denoted as 1A and 1B. The conformational effect of both conformers, as well as their protonated forms, were thoroughly studied using NMR spectroscopy, UV/Vis, and single crystal X‐ray diffraction analyses. Importantly, heating conformer 1B leads to its irreversible conversion to 1A, whereas in its protonated form, 1A ⋅ 2MSA undergoes irreversible transformation to 1B ⋅ 2MSA at lower temperatures. These temperature‐dependent features establish a foundation for developing new accumulated heat sensors, as demonstrated by the use of the present octaphyrins as a customized thermochromic indicator in steam sterilization. The present study thus underscores how the conformational rigidity of these new polypyrrolic macrocycles imparts properties that are distinct from historically flexible expanded porphyrinoids.

Impact of Conservation Tillage and Nitrogen Management on Soil Temperature and Soil Moisture in Aerobic Rice

This study investigates the impact of different tillage practices, namely Conventional Tillage (CT) (T1), Minimum Tillage with residue retention (MT) (T2) and Zero Tillage (ZT) (T3) and nitrogen fertilizer schedules 100% RDN (N1) (120 kg ha-1), 100% RDN + foliar spray of nano urea 2.5 ml l-1 at active tillering and panicle initiation stage (N2), 100% RDN + foliar spray of nano DAP 2.5 ml l-1 at active tillering and panicle initiation stage (N3), 75% RDN + Nano urea 2.5 ml l-1 at active tillering and panicle initiation stage (N4), 75 % RDN + Nano DAP 2.5 ml l-1 at active tillering and panicle initiation stage (N5) on soil temperature, moisture and their interaction in aerobic rice cultivation. Soil temperature was measured using digital thermometer and soil moisture was determined by Owen drying method. Results revealed that soil temperature and soil moisture was significantly influenced by tillage practices and Nitrogen fertilizer schedules showed no significant effect on soil temperature and soil moisture. Zero tillage (T3) consistently recording the lowest soil temperatures compared to T1 and T2 in both years. During rabi 2022-2023, T3 recorded 18.23°C in the 1st week, significantly lower than T1 (19.32°C). This trend persisted in the rabi 2023-2024, with T3 recording 27.1°C in the 19th week, significantly lower than T1 (28.61°C). In terms of soil moisture, zero tillage (T3) also consistently resulted in the highest moisture levels. During rabi 2022-2023 season, T3 recorded 18.93% soil moisture in the 1st week, significantly higher than T1 (18.11%). This pattern continued in the rabi 2023-2024, with T3 maintaining significantly higher moisture levels in most weeks. Zero tillage is effective in reducing soil temperature and enhancing soil moisture retention. Minimum tillage with residue retention performing similar to zero tillage.

Persistent Photoluminescence and Mechanoluminescence of a Highly Sensitive Pressure and Temperature Gauge in Combination with a 3D-Printable Optical Coding Platform.

Distinct types of luminescence that are activated by various stimuli in a single material offer exciting developmental opportunities for functional materials. A versatile sensing platform that exhibits photoluminescence (PL), persistent luminescence (PersL), and mechanoluminescence (ML) is introduced, which enables the sensitive detection of temperature, pressure, and force/stress. The developed Sr2MgSi2O7:Eu2+/Dy3+ material exhibits a linear relationship between ML intensity and force and can be used as an ML stress sensor. Additionally, the bandwidth of the PL emission band and the PL lifetime of this material are remarkably sensitive to temperature, with values of ≈0.05nmK-1 and 1.29%/K, respectively. This study demonstrates PersL pressure sensing for the first time, using long-lasting (seconds) lifetime as a manometric parameter. The developed material functions as an exceptionally sensitive triple-mode visual pressure sensor; specifically, it exhibits: i) a sensitivity of ≈-297.4cmGPa-1 (8.11nmGPa-1) in bandshift mode, ii) a sensitivity of ≈272.7cm-1/GPa (14.8nmGPa-1) in bandwidth mode, and iii) a sensitivity of 42%GPa-1 in PL-lifetime mode, which is the highest value reported to date. Notably, anti-counterfeiting, night-vision safety-sign, 8-bit optical-coding, and QR-code applications that exhibit intense PersL are demonstrated by 3D-printing the studied material in combination with a polymer.

Mtoto Wetu Growth and Temperature Monitoring System for Tanzania Child Healthcare Clinics

In most government maternal and child health (MCH) clinics in sub-Saharan countries caregivers rely on manual methods for data acquisition, storage, and analysis, leading to challenges such as errors, inefficiencies, and limited accessibility. Recognising the transformative potential of digital technology, this design aims to innovate the child growth monitoring paradigm by introducing a comprehensive Digitized Child Growth Monitoring System. The "Mtoto Wetu Growth and Temperature Monitoring System" is a comprehensive framework designed to monitor and assess the growth and temperature patterns of infants and young children on a monthly basis. This system integrates various components, including anthropometric measurements, temperature monitoring, immunisation schedule, automated growth chart generation, and parental, caregiver, and health care professionals’ involvement, to provide a holistic approach to child health monitoring. Implemented with standardised protocols, training sessions, and robust data management systems, the monitoring system aims to facilitate early detection of growth abnormalities, and health concerns. By promoting early intervention, preventive care measures, parental empowerment, and continuity of care, the Mtoto Wetu system strives to optimise health outcomes, foster parental engagement, and promote health equity among children. The system was able to provide results with a small amount of error compared to the standard weighing machines, tap measure and digital thermometer

Development of an enhanced electrical injera baking pan (Ethiopian Traditional mitad) using steel powder additives and gypsum insulation

Electric Injera baking Pan are prevalent in Ethiopia but are highly inefficient, resulting in significant heat loss, high energy consumption, and increased energy bills. This research investigates improving these devices using steel powder as an additive and gypsum as an insulator. The study examines thermal conductivity, baking time, energy consumption, heat loss, and insulation effectiveness. The objectives of this research are to improve the thermal conductivity of the baking surface while ensuring even heat distribution, enhance the insulation properties of the pan to reduce heat loss, improve the safety of the user by reducing the risk of excessive heat exposure to the outer surfaces, and reduce the overall energy consumption of the Injera baking process. Temperatures were measured using an infrared thermometer, digital thermometer, and thermocouple. Four samples (A0, A1, A2, & A3) with different steel powder compositions (0 %, 15 %, 25 %, and 35 %) and a constant 75 % clay soil composition were tested. The analysis showed an average baking energy of 0.45 kWh per kg of injera (0.198 kWh per injera) and a thermal efficiency of 86.4 % when baking 4.395 kg of injera. The total heat energy loss was 1402.78 KJ (14.08 % of 10300 KJ input energy). The losses were distributed among the retained (92.17 %), the baking plate (3.95 %), the bottom enclosure (2.08 %), the side enclosure (1.04 %), and the cover lid (0.76 %).

Parameter-Free Data Reduction for Short-Time Hypersonic Heat Flux Measurements

High-speed flows associated with hypersonics require significant, diverse, and successful ground-test campaigns before engaging in a flight test program. The present investigation focuses on demonstrating a new data reduction pathway for estimating the source heat flux using an elegant, though fragile, thin-film temperature gauge. The rapid response time of such sensors makes them well-suited for shock tunnel experiments. In such experiments, contaminated flow, composed of diaphragm debris, can often damage the sensing element. For the moment, the existence of an ideal coating (or even a hardened sensing element) is presumed that preserves the sensor’s survivability and accuracy over several test runs. A dynamic, physics-based data reduction methodology is proposed that accounts for the protective coating and that is applicable to millisecond testing times. This paper addresses three critical issues for acquiring the best estimate of the source heat flux. These issues include a) the formation of a baseline data reduction view that accounts for thin coatings; b) the development of a dynamic calibration method that removes the need for specifying thermophysical or geometrical properties; and c) the introduction of a time-scaling that allows for calibration to be performed in alternative and convenient time frames. This last point demonstrates the concept of the dimensionless time map and its novel consequences. The procedure is demonstrated on a reduced formulation, illustrating the merit of the concepts.

Body temperature, systemic inflammation and risk of adverse events in patients with acute coronary syndromes.

Inflammatory processes can trigger acute coronary syndromes (ACS) which may increase core body temperature (BT), a widely available low-cost marker of systemic inflammation. Herein, we aimed to delineate baseline characteristics of ST-segment elevation myocardial infarction (STEMI) and non-ST-segment elevation ACS (NSTE-ACS) patients stratified by initial BT and to assess its predictive utility towards major adverse cardiovascular events (MACE) after the index ACS. From 2012 until 2017, a total of 1044 ACS patients, 517 with STEMI and 527 with NSTE-ACS, were prospectively recruited at the University Hospital Zurich. BT was measured by digital tympanic thermometer along with high-sensitivity C-reactive protein (hs-CRP) and cardiac troponin-T (hs-cTnT) levels prior to coronary angiography. Patients were stratified according to initial BT and uni- and multivariable regression models were fit to assess associations of BT with future MACE risk. Among patients with STEMI, BT was not predictive of 1-year MACE, but a U-shaped relationship between BT and MACE risk was noted in those with NSTE-ACS (p = .029), translating into a 2.4-fold (HR, 2.44, 95% CI, 1.16-5.16) increased 1-year MACE risk in those with BT >36.8°C (reference: 36.6-36.8°C). Results remained robust in multivariable-adjusted analyses accounting for sex, age, diabetes, renal function and hs-cTnT. However, when introducing hs-CRP, the BT-MACE association did not prevail. In prospectively recruited patients with ACS, initial BT shows a U-shaped relationship with 1-year MACE risk among those with NSTE-ACS, but not in those with STEMI. BT is a broadly available low-cost marker to identify ACS patients with high inflammatory burden, at high risk for recurrent ischaemic events, and thus potentially suitable for an anti-inflammatory intervention. ClinicalTrials.gov Identifier: NCT01000701.

Effect of Pressure Loading on Heel Skin Temperature and Moisture in Healthy Volunteers: Preliminary Results.

Recent studies emphasize the significance of skin microclimate in the prevention of pressure injuries (PI). The objective was to evaluate the effect of pressure loading on skin temperature and moisture in the heels of healthy adults. This is a before-and-after study performed at Brazil, in October 2022. Skin temperature (°C) was measured by an infrared digital thermometer, and skin moisture (%) using electrical bioimpedance. Ten individuals/twenty heels were evaluated. The average temperature of the right and left heel was the same at baseline (27.2 °C). It was recognized that after 30 min of pressure loading on the heels, there was a decrease in temperature, and after 15 min of pressure offloading, the temperature decreased again. It was found that at t0, the moisture of the right heel (12.6%) was lower than the left heel (15.6%). The median moisture in the right heel increased from t0 to t1 and decreased in t2, while in the left heel, there was a small variation of the median from t0 to t1, as well as to t2. The pressure loading leads to a decrease in temperature and changes the skin moisture of the heels of healthy individuals.

Computational advances for energy conversion: Unleashing the potential of thermoelectric materials

Thermoelectric (TE) materials have lately attracted a lot of attention and sparked a flurry of research because of their potential for energy conversion and broad spectrum of applications, including waste heat recovery, thermocouples, sensors, and refrigeration. Additionally, they could potentially be able to offer extremely effective and eco-friendly methods for energy production and harvesting, which might aid in addressing the world's energy concerns. Concerning the advancement in condensed matter physics, although a plethora of research has been devoted to identifying suitable TE materials over the years, there is still scope for the exploration of new materials. This review article strives to project extensive progress in the field of thermoelectricity, commencing with a discussion on various classes of TE materials scrutinized based on TE coefficients such as thermopower, power factor, and thermal conductivity computed within the framework of DFT, combined with an in-depth look at the computational techniques used. A wide range of prospective TE material classes, including chalcogenides, pnictides, oxides, perovskites, transition metal dichalcogenides (TMD), and a few more, are meticulously addressed, stressing the unique characteristics of each class in separate sections and subsections. SrAgChF (Ch = S, Se, Te), with its superlattice structure, boasts high thermopower for both carriers, making it ideal for power generation. Similarly, ThOCh (Ch = S, Se, Te) and NbX2Y2 (X = S, Se, Y = Cl, Br, I) chalcogen materials exhibit significant thermoelectric properties in both bulk and monolayer forms. Fe2GeCh4 (Ch = S, Se, Te) demonstrates exceptional anisotropic TE characteristics, advantageous for device applications. Structurally resembling chalcopyrites, Zn-based pnictides show high efficiency, validated by the analysis of power factor scaled by temperature and relaxation time (S2σT/τ: where S is thermopower, σ is electrical conductivity, S2σ is power factor, T is temperature and τ is the relaxation time). Moreover, CaLiPn (Pn = As, Sb, Bi) emerges as more favorable for TE applications than SrLiAs, displaying low lattice thermal conductivity. Among transition metal dichalcogenides (TMDs), OsX2 (S, Se, Te) exhibits high thermopower, while FeS2 displays remarkable thermoelectric properties in both marcasite and pyrite structural phases. In exploring 2D materials akin to graphene, ReS2's TE properties have been scrutinized across various forms, showcasing significant potential, especially when tailored for flexibility. Compounds like CaSrX (X = Si, Ge, Sn, Pb) and ZnGeSb2 exhibit notable TE features, indicating avenues for strain-engineered modulation of TE properties. Lattice dynamics play a pivotal role in TE efficiency, driving investigations into phonon dispersion and thermal properties across materials. CsAgO's remarkably low lattice thermal conductivity highlights its promise as a TE material. Despite the effectiveness of semiclassical approximations, accurately predicting transport parameters requires accounting for scattering effects. Incorporating such factors is essential for precise estimation of the thermoelectric figure of merit (ZT). Notably, CsAgO's low lattice thermal conductivity contributes to its effectiveness, boasting a ZT exceeding 1.4. Layered compounds like CuTlX (X = S, Se) exhibit extreme anisotropy in lattice thermal conductivity and achieve ZT values surpassing one at 300 K. LaAgXO (X = Se, Te) shows a high ZT exceeding 2.5, particularly under heavy carrier doping. The best aspects of the compounds studied, the future of TE materials in the context of device application, the development of flexible and wearable TE materials, and strategies for improving TE parameters are all discussed in this review's conclusion.

Unsteady relationships between instantaneous surface heat flux, instantaneous surface temperature, and tracked shock wave phenomena

Investigated are unsteady relationships between surface heat flux variations, surface temperature fluctuations, and tracked shock wave phenomena. The level of coherence and time lag between events at different flow locations are used to quantify the associated interactions at different frequencies. With this approach, time-varying surface heat flux and surface temperature fluctuations are used to track events at different flow locations relative to unsteadiness associated with the test section inlet and relative to unsteadiness associated with different shock wave phenomena. Employed for the investigation is a specialty test section with an inlet Mach number of 1.54, which contains a normal shock wave, a lambda foot (which is comprised of an upstream oblique shock wave leg, and a downstream oblique shock wave leg), and a flow separation zone beneath the lambda foot. High and low unsteady Mach wave intensity levels are produced at the test section inlet by different numbers and different amounts of unsteadiness of families of intersecting and interacting Mach waves, as these are located within and just downstream of the test section entrance. When correlated with respect to normal shock wave tracked locations, values and magnitudes of the most highly correlated frequency bands are different depending upon the level of test section inlet unsteady Mach wave intensity, and the location where unsteady flow events originate. With low freestream unsteady Mach wave intensity at the test section inlet, unsteady events are generally present at normal shockwave locations prior to times when their influences are present at thin film temperature and heat flux gage surface locations. The presence of high unsteady Mach wave intensity at the test section inlet produces an environment wherein the low Mach wave intensity inlet flow is overwhelmed by highly active Mach wave fluctuations, when they are present, such that the normal shock wave is no longer a primary originating source of flow unsteadiness.

Review of Modern Forest Fire Detection Techniques: Innovations in Image Processing and Deep Learning

Fire detection and extinguishing systems are critical for safeguarding lives and minimizing property damage. These systems are especially vital in combating forest fires. In recent years, several forest fires have set records for their size, duration, and level of destruction. Traditional fire detection methods, such as smoke and heat sensors, have limitations, prompting the development of innovative approaches using advanced technologies. Utilizing image processing, computer vision, and deep learning algorithms, we can now detect fires with exceptional accuracy and respond promptly to mitigate their impact. In this article, we conduct a comprehensive review of articles from 2013 to 2023, exploring how these technologies are applied in fire detection and extinguishing. We delve into modern techniques enabling real-time analysis of the visual data captured by cameras or satellites, facilitating the detection of smoke, flames, and other fire-related cues. Furthermore, we explore the utilization of deep learning and machine learning in training intelligent algorithms to recognize fire patterns and features. Through a comprehensive examination of current research and development, this review aims to provide insights into the potential and future directions of fire detection and extinguishing using image processing, computer vision, and deep learning.

Diphenylacetylene-Incorporating Octaphyrin: A Rigid Macrocycle with Readily Separable Conformational Isomers.

An expanded carbaporphyrinoid analogue, octaphyrin(2,1,1,1,2,1,1,1), containing two rigid diphenylacetylene moieties is reported. In contrast to traditional pyrrolic macrocycles where flexible conformers coexist in dynamic equilibrium, this macrocycle exists as two separable, conformationally stable stereoisomers, denoted as 1A and 1B. The conformational effect of both conformers, as well as their protonated forms, were thoroughly studied using NMR spectroscopy, UV-Vis, and single crystal X-ray diffraction analyses. Importantly, heating conformer 1B leads to its irreversible conversion to 1A, whereas in its protonated form, 1A·2MSA undergoes irreversible transformation to 1B·2MSA at lower temperatures. These temperature-dependent features establish a foundation for developing new accumulated heat sensors, as demonstrated by the use of the present octaphyrins as a customized thermochromic indicator in steam sterilization. The present study thus underscores how the conformational rigidity of these new polypyrrolic macrocycles imparts properties that are distinct from historically flexible expanded porphyrinoids.

Rancang Bangun Green Portable Cooler Box

Freon is one of the refrigerants used in refrigeration systems. The refrigeration system has a very important role, namely to preserve food ingredients so that food can last longer. The use of freon is not only used in ships but is widely found in home appliances in refrigeration systems used in freezers, air conditioners, refrigerators, and dispensers. If more freon is used, the negative impact that arises is greater, namely the depletion of the ozone layer and global warming which can have a bad influence on health, the life of living things and the environment. The purpose of this researcher is to create a tool to reduce the negative impact of freon use, namely by using peltier as a cooling medium with environmentally friendly thermoelectric modules. This study uses trial and error methods. Where the trial process is carried out by turning on one of the working push buttons and observing the temperature value. Then it is processed by the control system, namely Arduino Mega which will later provide a PWM output signal to the IRF540 mosfet when the output temperature value is in line with the reference value and vice versa. The test of this tool was carried out by comparing measurements between the author's prototype tool and the standard measuring tool, namely the digital thermometer. Based on the test results, this device can produce a minimum temperature of 140C at 30-minute intervals without any media. The trial using 330ml bottled water can reach a temperature of 170C within 30 minutes in the cooler box. This tool is also equipped with an automatic monitoring system using a PWM signal in the form of a change in fan speed, which is 255 RPS maximum speed and when getting a PWM signal it changes to 50 RPS. The percentage of errors resulting from the comparison of standard measuring instruments and sensor values had the highest and lowest percentages of 2.37% and 0.84% in cold dispersion conditions without charge. Then the highest and lowest error percentages were 1.69% and 0.72% in the state of containing a load of 1 330ml mineral bottle. This ptototype uses data recording using Micro-SD as a data logger.

An activation guideline for the resistive heating process of iron-based shape memory alloy embedded in concrete

In new and existing reinforced concrete (RC) structures, extensive research has proven that iron-based shape memory alloys (Fe-SMA) can be used as prestressing materials. As for the Fe-SMA embedded in concrete, the resistive heating method is usually adopted to activate its shape memory effect to develop prestress in the concrete. The prestressing process of the Fe-SMA involves multiple physical fields such as electric currents, temperatures, and mechanics. An accurate and standardized implementation of the activation process is essential for the Fe-SMA to effectively generate the expected prestress in the structure. However, data drift can occur when thermocouples measure the temperature of the Fe-SMA through which current flows and non-contact heat sensors can not measure the temperature of the Fe-SMA embedded in the concrete. It is also difficult to theoretically estimate the activation time and temperature of the Fe-SMA in concrete. The pre-test or empirical values are usually required to estimate the activation current and time for reaching the target temperature, compromising the construction efficiency. Additionally, the selection of activation parameters varies wildly for Fe-SMA with different specifications and sizes. There are currently no standardized guidelines for the electrical resistive activation of the Fe-SMA. Therefore, a multi-physical finite element model was developed to study the self-prestressing process of the Fe-SMA embedded in concrete and predict the temperature distribution and prestress of the Fe-SMA and concrete. The effects of the current density, the Fe-SMA shape and size, and the concrete cover depth were analyzed. In the end, an activation guideline for the electrical resistive heating of the Fe-SMA was offered to facilitate the construction and activation process in field engineering.

High prevalence and risk factors associated with asymptomatic malaria among children in Nkwen village, Northwest Region, Cameroon

BackgroundIn endemic locations, asymptomatic malaria is a major contribution to the rise in clinical malaria. In order to achieve the goal of interrupting malaria transmission, control programmes should take into consideration carriers of asymptomatic malaria parasite. Hence, the purpose of this study was to look at the prevalence and risk factors of asymptomatic malaria in children in Nkwen village.MethodsUsing a cross-sectional and community-based design, conducted between June and December 2022, a total of 246 children were enrolled after obtaining informed and signed consent from parents and/ or guardians. To collect data, pre-tested, closed-ended, structured questionnaires were used, ensuring the accuracy and reliability of the information gathered. A digital thermometer with infrared forehead capability was used to take participants’ body temperature, providing precise measurements and respondents with temperature < 37.5 °C, and not presenting any symptoms or indicators of malaria were included in the study, ensuring the focus on asymptomatic cases. Blood samples were collected by venipuncture and screened for the presence of asymptomatic parasitaemia using blood smear microscopy and nested polymerase chain reaction (PCR). Data was entered into Microsoft Excel worksheet and analysed using SPSS version 23 software. Logistic regression models were carried out to explore the risk factors associated with asymptomatic malaria at household and individual levels and statistically significant association was considered at a p-value < 0.05.ResultsA total of 246 healthy children were examined for asymptomatic malaria infection using microscopy and PCR. Of the examined children, 65.9% (162/246) were malaria positive by PCR while 59.3% (146/246) were malaria positive by microscopy. Considering both diagnostic methods, females had a greater prevalence of asymptomatic malaria than males. In logistic analysis, the risk of developing asymptomatic malaria was associated several factors: previous malaria episode (OR = 5.14; CI 2.94–9.01), family history of malaria (OR = 3.86; CI 2.21–6.74), homestead near swampy areas (OR = 3.56; CI 2.10–10.61), non-utilization of insecticide treated nets (OR = 4.36; CI 2.53–7.5), non-usage of indoor residual spray (IRS) (OR = 6.67; CI 3.75–11.86) and opened eaves (OR = 3.86; CI 2.21–6.74). No associations were established between asymptomatic malaria and the following factors: age group (p > 0.05), gender (p > 0.05) and type of wall construction (p > 0.05).ConclusionThe high rate of asymptomatic malaria in this study is a significant problem and may jeopardize the current malaria control effort. Personal and house-level risk factors were linked with asymptomatic malaria. Therefore, it should be considered when evaluating and restructuring more successful malaria elimination tactics to accomplish the intended goals of malaria control.

Parameter identification of linear systems with heat sensors subject to unknown space-varying parameters

We extend existing works on control of (finite-dimensional) linear systems with (infinite-dimensional) heat sensors [6]. The extension lies on the one hand, in the fact that all system poles and zeros are unknown and, on the other, in the fact that sensor equations include unknown spatially-varying parameters. These uncertainties make the problem of parameter identification quite challenging. The existing adaptive observers for this type of systems prove not to be applicable in the presence of these uncertainties. Presently, we develop an identification method that involves multi-sine exciting input signals. Doing so, the inaccessible signal at the junction point, between the system and the sensor, can be given an affine parameterized form. It turns out that the identification problem of the sensor is decoupled from that of the system. Then, a parameter estimator involving K-filters is designed to get estimates of the sensor parameters as well as those of the inaccessible signal at the junction point. A new persistent excitation concept is introduced that ensures exponential convergence of the sensor parameter estimates and the estimated junction signal. The latter is then used to identify the parameters of the system dynamics.

Assessment of the accuracy and reliability of clinical thermometers for body temperature measurements at the hospital: a laboratory study

Abstract This study aims to assess the accuracy and reliability of two different types of thermometers: contact thermometers (CT) and non-contact thermometers (NCIRT) at Maharaj Nakorn Chiang Mai Hospital. The comparison method was carried out in a hospital laboratory setting and followed a specific calibration procedure. The mean readings, errors, and measurement uncertainties were reported and categorized according to the manufacturer’s labeling models. The maximum permissible errors were defined by international standards and clinical acceptances for contact and NCIRTs, respectively. The results showed that thermometers of temperature probes (PTs) provided the highest level of accuracy. When compared to a reference standard thermometer (STD), the mean errors were only 0.04 °C at the calibration point of 37.0 °C. For digital CTs, the mean error at the calibration points of 37.0 °C was 0.24 °C. Most CT models exhibited high accuracy and reliability. However, the forehead (IRFTs) and ear (IRETs) readings significantly differed from the STD, with over half of all units not meeting the ISO 80601–2–56/ASTM E1965–98 standard requirements. These results suggest that CTs and PTs are highly accurate and reliable devices for measuring body temperature. However, both IRFTs and IRETs could be useful in certain situations, such as screening many people in a short amount of time, but their accuracy should be interpreted with caution and confirmed using a more precise method if necessary.