Performance Analysis of a Floating Photovoltaic System and Estimation of the Evaporation Losses Reduction

Our research aims to achieve dual-positive effects in the presented study by raising photovoltaic (PV) panels over the water surface. With this, target experiments were primarily conducted to evaluate the efficiency increments of the PV panel while reducing its operating temperature through passive convective cooling obtained by raising it over water. The following objective was to estimate the reduction in water evaporation due to the shading effect induced by the panel placed inside the same basin. The performance of two PV panels was analyzed, one used for tests, the other as a reference. The characteristic curves were determined under the local environmental conditions of Cagliari, Italy. The true temperature reduction and efficiency gain calculations of panel P1 due to water cooling was achieved via the measured temperatures and calculated efficiencies of panel P2 at environmental conditions. The water height inside the basin was constantly monitored and maintained at approximately 7.5 cm below panel P1, which covered about 17% of the total water surface area. The presence of water underneath P1 leads to its efficiency increment on average by 2.7% (absolute) and about 17.22% (relative). At the same time, temperature of panel P1 dropped by 2.7 °C on average. The comparative water evaporation study conducted with and without P1 inside the basin showed a 30% reduction in water evaporation.

Long-Wave Infrared Imaging for Intraoperative Cancer Detection—What is the True Temperature of a Cancer?

Background During cancer operations, the cancer itself is often hard to delineate—buried beneath healthy tissue and lacking discernable differences from the surrounding healthy organ. Long-wave infrared, or thermal, imaging poses a unique solution to this problem, allowing for the real-time label-free visualization of temperature deviations within the depth of tissues. The current study evaluated this technology for intraoperative cancer detection. Methods In this diagnostic study, patients with gastrointestinal, hepatobiliary, and renal cancers underwent long-wave infrared imaging of the malignancy during routine operations. Results It was found that 74% were clearly identifiable as hypothermic anomalies. The average temperature difference was 2.4°C (range 0.7 to 5.0) relative to the surrounding tissue. Cancers as deep as 3.3 cm from the surgical surface were visualized. Yet, 79% of the images had clinically relevant false positive signals [median 3 per image (range 0 to 10)] establishing an accuracy of 47%. Analysis suggests that the degree of temperature difference was primarily determined by features within the cancer and not peritumoral changes in the surrounding tissue. Conclusion These findings provide important information on the unexpected hypothermal properties of intra-abdominal cancers, directions for future use of intraoperative long-wave infrared imaging, and new knowledge about the in vivo thermal energy expenditure of cancers and peritumoral tissue.

Thermal Fault Diagnosis of Electrical Equipment in Substations Based on Image Fusion

Infrared thermal imaging can diagnose whether there are faults in electrical equipment during non-stop operation. However, the existing thermal fault diagnosis algorithms fail to consider an important fact: the infrared image of a single band cannot fully reflect the true temperature information of the target. As a result, these algorithms fail to achieve desired effects on target extraction from low-quality infrared images of electrical equipment. To solve the problem, this paper explores the thermal fault diagnosis of electrical equipment in substations based on image fusion. Specifically, a registration and fusion algorithm was proposed for infrared images of electrical equipment in substations; a segmentation and recognition model was established based on mask region-based convolutional neural network (R-CNN) for the said images; the steps of thermal fault diagnosis were detailed for electrical equipment in substations. The proposed model was proved effective through experiments.

Tungsten Ores of the Dzhida W-Mo Ore Field (Southwestern Transbaikalia, Russia): Mineral Composition and Physical-Chemical Conditions of Formation

This article discusses the peculiarities of mineral composition and a fluid inclusions (FIs further in the text) study of the Kholtoson W and Inkur W deposits located within the Dzhida W-Mo ore field (Southwestern Transbaikalia, Russia). The Mo mineralization spatially coincides with the apical part of the Pervomaisky stock (Pervomaisky deposit), and the W mineralization forms numerous quartz veins in the western part of the ore field (Kholtoson vein deposit) and the stockwork in the central part (Inkur stockwork deposit). The ore mineral composition is similar at both deposits. Quartz is the main gangue mineral; there are also present muscovite, K-feldspar, and carbonates. The main ore mineral of both deposits is hubnerite. In addition to hubnerite, at both deposits, more than 20 mineral species were identified; they include sulfides (pyrite, chalcopyrite, galena, sphalerite, bornite, etc.), sulfosalts (tetrahedrite, aikinite, stannite, etc.), oxides (scheelite, cassiterite), and tellurides (hessite). The results of mineralogical and fluid inclusions studies allowed us to conclude that the Inkur W and the Kholtoson W deposits were formed by the same hydrothermal fluids, related to the same ore-forming system. For both deposits, the fluid inclusion homogenization temperatures varied within the range ~195–344 °C. The presence of cogenetic liquid- and vapor-dominated inclusions in the quartz from the ores of the Kholtoson deposit allowed us to estimate the true temperature range of mineral formation as 413–350 °C. Ore deposition occurred under similar physical-chemical conditions, differing only in pressures of mineral formation. The main factors of hubnerite deposition from hydrothermal fluids were decreases in temperature.

THERMAL IMAGING STUDIES OF THE ORIGINAL HEAT EXCHANGER PLATE

A modern method for studying the temperature field of heated bodies is considered. The object under study is a corrugated heat exchange plate with an original geometry. Heat exchangers are one of the main types of process equipment in heat supply systems. The article presents a comparison of two main types of heat exchange equipment: shell-and-tube and plate devices. The FLIR i50 thermal imaging device is characterized. A comparison is made between a standard heat exchange plate and a corrugated plate with spherical recesses located linearly on the areas between the corrugations. The use of original plates can increase the efficiency of the heat exchange process due to increased turbulization of the coolant. The relationship between the true temperature of a heated body and the brightness temperature of a black body is established. Experimental studies are carried out, in result the value of the average temperature of the heated body is obtained. This value is necessary for further calculation of heat transfer coefficients, which, in turn, are decisive in calculating the main parameter that characterizes the efficiency of heat exchange equipment-the heat transfer coefficient. The use of thermal imaging is the original way to study heat transfer processes, allowing to show the real increase of heat transfer coefficient of a plate heat exchanger.

Indirect Measurement of Forest Canopy Temperature by Handheld Thermal Infrared Imager through Upward Observation

The influence of leaf temperature on transpiration, photosynthesis, respiration, and other metabolic activities is critical to plant growth, development, production and distribution. However, traditional measurement of canopy temperature by thermocouples or thermal infrared thermometers is laborious and difficult, especially for tall trees. The recent development of a handheld thermal infrared imager has made it possible to perform high temporal and spatial canopy temperature measurements efficiently. However, the signal recorded by the sensor is often a mixture of radiation from the target and the atmosphere, which must be corrected to get the true temperature. In this study, we propose a ground-based indirect measurement method of canopy temperature by a handheld thermal infrared imager through upward observation. Visible and thermal images are combined to distinguish the canopy pixels and sky pixels. To remove the atmospheric radiation from the sky, an empirical atmospheric model is established, which can perform atmospheric correction accurately and efficiently. To validate the proposed method, we collected canopy temperatures of 36 species of trees with a FLIR T420 thermal infrared imager and compared the estimated temperatures with those directly measured by thermocouples. The accuracy of the corrected canopy temperature has been significantly improved with mean absolute error reduced from 3.73 °C to 0.64 °C. This proposed canopy temperature measurement method can be used to various applications in remote sensing product validation, and ecosystem and forestry studies.

Development of a Pyrometer That Measures the True Temperature Field of the Two-Dimensional Array

This paper develops a two-dimensional array pyrometer, which can measure the true temperature field of the two-dimensional array. The pyrometer consists of an optical part, a circuit part and a software part. In the optical part, the radiation energy of the two-dimensional array target is obtained by scanning with the rotating mirror. Then, the radiation signal is converted and amplified by the circuit part. The software component realizes the functions of the pyrometer calibration, signal acquisition and data processing. The data processing adopts the secondary measurement method to calculate the true temperature and uses the multi-threaded method to improve the operational efficiency. Experiments show that the uncertainty of the two-dimensional pyrometer array can reach 1.43%. Compared with the single-threaded method, the true temperature operation time of the two-dimensional pyrometer array is improved by 77%, which verifies that the software operational efficiency is greatly improved.

Testing the ideal ice-core record for past temperature reconstructions using combined isotope and impurity analyses

<p>Ice cores represent one of the most important palaeoclimate archives, which record, among many other parameters, changes in stable oxygen and hydrogen isotopic composition and soluble ionic impurities. While impurities serve, for example, as proxies for sea ice, marine biological activity and volcanism, records of isotopic composition are the major proxy for the reconstruction of natural polar temperature variability. The latter is based on the temperature-dependent distillation and fractionation of the isotopic composition of water vapour along its atmospheric pathway and empirically determined relationships thereof.</p><p>However, temperature is by far not the only driver of isotopic composition changes. A single isotopic ice-core record will comprise variations caused by a multitude of processes, from variable atmospheric circulation and moisture pathways to the intermittency of precipitation and finally to the mixing and re-location of surface snow by wind drift (stratigraphic noise). Taken together, these additional processes constitute a large amount of noise in the single isotope record, which masks the true temperature-related variability. Averaging a sufficient number of records to reduce overall noise is one means to allow for quantitative reconstructions, but its effectiveness depends on the spatial scales of the involved processes. Here, we discuss an alternative approach. Assuming that major impurity species exhibit a seasonal cycle and are mainly also, along with the isotopic composition, deposited by precipitation and redistributed by wind, a large portion of their interannual variability should be linked, which would offer the possibility of using the impurities to correct the variability of the isotopic records.</p><p>In this contribution, we present the "ideal" dataset for testing this idea. We sampled and analysed isotopic composition and major impurity species on a four metre deep and 50 metre long trench at Kohnen Station, East Antarctica. This enables us to study the two-dimensional structure and relationship of both proxies to learn about their deposition mechanisms, their seasonality, and to test the ability of a combined isotope–impurity approach to reconstruct local temperatures by comparing so obtained temperature reconstructions with the local weather station data.</p><p> </p>

SVEEEETIES: singular vector expansion to estimate Earth-like exoplanet temperatures from infrared emission spectra

Context. Detailed characterizations of exoplanets are clearly moving to the forefront of planetary science. Temperature is a key marker for understanding atmospheric physics and chemistry. Aims. We aim to retrieve temperatures of N2-O2 dominated atmospheres from secondary eclipse spectroscopic observations of the thermal emission of Earth-like exoplanets orbiting G-, K-, and M-stars, using large-aperture future space telescopes. Methods. A line-by-line radiative transfer code was used to generate synthetic thermal infrared (TIR) observations. The atmospheric temperature is approximated by an expansion with the base vectors defined by a singular value decomposition of a matrix comprising representative profiles. A nonlinear least squares fitting was used to estimate the unknown expansion coefficients. Results. Analysis of the 4.3 and 15 μm CO2 bands in the TIR spectra permits the inference of temperatures even for low signal-to-noise ratios of 5 at medium resolution. Deviations from the true temperature in the upper troposphere and lower-to-mid stratosphere are usually in the range of a few Kelvin, with larger deviations in the upper atmosphere and, less often, in the lower troposphere. Although the performance of the two bands is equivalent in most cases, the longwave TIR is more favorable than the shortwave due to increased star-planet contrast. A high spectral resolution, as provided by the James Webb Space Telescope (JWST) instruments, is important for retaining sensitivity to the upper atmosphere. Furthermore, the selection of an appropriate set of base functions is also key. Conclusions. Temperature in the mid-atmosphere, relevant for understanding habitability, can be suitably characterized by infrared emission spectroscopy with a resolution of at least 1000 (ideally ≈2500). Obtaining the necessary signal-to-noise ratio will be challenging even for JWST, however, it could be feasible with future space missions, such as the Origins Space Telescope or the Large Interferometer for Exoplanets. In the meantime, a least squares fitting with an appropriate set of base functions is also applicable for other classes of planets.

Evaluation of Electromagnetic Exposure to Heavy Oil Stock

One of the promising and environmentally acceptable ways to radically solve the problem of improving the quality of bitumen is the creation of an intensive physical and chemical technology for their production based on the use of residual oil fractions activated by an electromagnetic field. The task of maximizing the involvement of heavy oil residues in refining is very urgent in the face of increasing competition in the oil products market, on one side, and viseversa the background of inceciment of demands on their quality in view of environmental protect, on the other side. To assess the potential of high viscosity oils and natural bitumen and, as well as conventional oils, it is necessary to conduct thorough investigations to determine the curves of the true temperature curve (TTC), density, sulphur content, low temperature and viscosity features, fractional and hydrocarbon compositions. It has been established that prolonged irradiation has a destructive effect on most known organic particles. So, there is a request to study the performance features of materials like plastics, coatings and bitumen in the area of electromagnetic radiation and its capability to withstand exposure to radiation. The effect of electromagnetic radiation on organic parts has recently been investigated to evaluate the impact of electromagnetic waves on bituminous materials, specially for asphalts, and to utilize in practice the data gained. Bituminous particels vary significantly in their composition that relates to the resource of raw particles and the method of obtaining the particles.