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This research presents the design, construction, and experimental evaluation of a novel box-type solar oven optimized for enhanced thermal efficiency and heat retention, developed to address the challenges of sustainable cooking in temperate climates. The solar oven, measuring 120 cm × 60 cm × 45 cm, incorporates strategically designed rock wool insulation and 5 kg of steel plates as thermal mass, along with a double-glazed glass cover tilted at an experimentally optimized angle of 15° relative to the horizontal plane. Extensive experimental testing was conducted in Viseu, Portugal (40° N latitude) under varying meteorological conditions, including solar irradiance levels ranging from 400 to 900 W/m2 and wind speeds of up to 3 m/s. The results demonstrated that the oven consistently achieved internal temperatures exceeding 160 °C, with a peak temperature of 180 °C, maintaining cooking capability even during periods of intermittent cloud cover. Quantitative analysis showed that the thermal efficiency of the oven reached a peak of 38%, representing a 25–30% improvement over conventional designs. The incorporation of thermal mass reduced temperature fluctuations by up to 40%, and the enhanced insulation reduced conductive heat loss by approximately 30%. Cooking tests validated the oven's practical effectiveness, with the successful preparation of various foods including rice (90 min), cake (120 min), vegetables (60 min), and bread (110 min). This study provides comprehensive performance data under different meteorological conditions, including detailed temperature profiles, heating rates, and thermal efficiency measurements. By addressing key limitations of prior models, particularly the challenge of temperature stability during variable solar conditions, the proposed solar oven offers a cost-effective, efficient solution that can be adapted for use in diverse climates and regions, with particular relevance to areas seeking sustainable alternatives to traditional cooking methods. [ABSTRACT FROM AUTHOR]

The growing global energy demand, particularly in India, calls for innovative strategies to improve building energy efficiency. With buildings contributing significantly to energy consumption, especially in cooling-dominated climates, sustainable insulation materials are essential in minimizing energy usage. This study explores the potential of bamboo biochar, fly ash, and lime as sustainable insulation materials for building envelopes. This study also addresses the critical issue of energy efficiency in building construction, specifically focusing on the comparative analysis of three materials for their thermal performance, environmental impact, and economic viability. This research aims to identify the most sustainable material choice by assessing each material's life cycle energy consumption, thermal resistance, and associated costs. The research methodology involves an extensive review of 125 relevant studies to assess the thermal performance of these materials. U-values were computed from the reported thermal conductivity data and systematically arranged in chronological order to evaluate and compare their insulation effectiveness over time. Additionally, these materials were analyzed under sustainability criteria, incorporating life cycle analysis and a carbon footprint assessment. This study identifies existing research gaps and offers recommendations for future research, creating structure for the development of sustainable insulation system. [ABSTRACT FROM AUTHOR]

Strain sensors are often used to monitor the use of critical components. The bond strength between the strain sensor and the gear teeth is particularly critical. There is a problem of insufficient bond strength between separated strain sensors and parts. The strain sensor is prone to loosening and flaking in the working environment. Therefore, a method of preparing the ceramic insulation layer of the strain sensor by direct laser deposition (DLD) is proposed. The effects of laser scanning trajectories, laser power, and scanning speed on forming quality were investigated experimentally. In addition, the phase analysis, microstructure characterization, and insulation properties of the insulating layers prepared at different overlap rates were researched. The research shows that the ceramic insulation layer has good insulation properties and hardness. The maximum hardness can reach 2405.74MPa, and the insulation resistance increases with the number of layers. The surface of the ceramic insulation layer is dense and has no cracks. [ABSTRACT FROM AUTHOR]

Replacing thermoset insulation by healable and recyclable covalent adaptable networks is a promising approach to the sustainable development of electrical and electronic devices. However, the repair performance gifted by dynamic covalent bonds always conflicts with the excellent mechanical properties gifted by stiff cross‐linked networks. In this paper, by introducing dynamic thiocarbamate bonds, polythiourethane (PTU) with excellent mechanical properties and electrical insulation comparable to commercial epoxy resins are successfully developed, which exhibit superior healability and recyclability properties. Sub‐centimeter scale electrical breakdown failures of the PTU samples could be efficiently self‐healed with a healing efficiency up to 90%, while the storage modulus and volume resistivity exceeded 2 GPa and 1016 Ω cm, respectively. Even though the electrical breakdown strength inevitably declined after multiple repair processes, PTU samples could restore their initial excellent insulation performance by simply reprocessing with the efficiency above 95%. Moreover, the efficient healability performance of large‐sized electrical breakdown failures remained after the reprocessing. These outstanding characteristics underscore the tremendous potential of PTU materials as a new generation of sustainable high voltage insulation. [ABSTRACT FROM AUTHOR]

Upcycling of low valuable plastic waste into materials with enhanced properties helps progress toward establishing a plastics circular economy. Furthermore, implementing recyclability as a core design criterium for newly formed materials can significantly increase their impact on sustainability, yet rarely explored. In this work, the upcycling of polystyrene (PS) waste is presented into closed‐loop recyclable high‐performance aerogels. Through a simple post‐functionalization process, PS is aminated to generate a polyfunctional amine, which is then reacted with aldehydes to form a recyclable cross‐linked imine network. This network is subsequently dried to produce poly(styrene‐imine) aerogels (PSAs). The resulting PSAs exhibit excellent thermally insulating properties, along with low density, outstanding mechanical strength, and intrinsic hydrophobicity. More importantly, these aerogels show quantitative depolymerization under acidic aqueous conditions, back to their original precursors which can be recovered in high yield and purity and reused for the synthesis of fresh aerogels with nearly identical material properties, thus achieving closed‐loop recycling. This work presents an efficient method for upcycling of chemically non‐recyclable plastics into recyclable and high value‐added advanced aerogel materials, offering a new pathway for establishing a circular economy for plastics. [ABSTRACT FROM AUTHOR]

This study investigates the mechanical properties and erosion resistance of high temperature–pressure carbon‐epoxy novolac insulation reinforced with ZrB2/SiC particles. For this reason, at first, five samples were fabricated using the hot press, which included resin epoxy novolac EPN1180 base without reinforcement and four samples containing resin with 20:80, 30:70, 40:60, and 50:50 of SiC: ZrB2 particles respectively. After manufacturing of the samples, the mechanical properties were evaluated through bending and tensile testing, followed by erosion resistance properties by the use of oxyacetylene flame erosion tests. Chemical composition and surface morphology analysis of the composites were conducted using energy‐dispersive spectroscopy, scanning electron microscopy, and x‐ray diffraction analysis. Results indicate that the addition of ceramic particles enhances both mechanical properties and erosion resistance of the composite. The pure resin sample exhibited the highest weight loss and thickness reduction, while the sample containing 40% SiC and 60% ZrB2 demonstrated the least weight loss and thickness reduction about 55% and 83% respectively compared to pure sample. Additionally, the sample with 30% SiC and 70% ZrB2 had the lowest backside temperature. Furthermore, the sample with 20% SiC and 80% ZrB2 exhibited the highest mechanical properties, with a tensile strength of 422.5 MPa and flexural strength of 587.11 MPa. Morphological analysis revealed the presence of phases such as SiO2, ZrO2, and ZrSiO4 attributable to the ZrB2/SiC particles, contributing to the enhancement of erosion resistance. Highlights: Examines volume ratios of ZrB2/SiC.Discovers the best particle ratio (20%SiC, 80%ZrB2) for mechanical properties.Identifies the best particle ratio (30% SiC, 70% ZrB2) for erosion resistance.Reveals key phases enhancing erosion resistance with advanced analysis methods.Linear and mass ablation rate improved by 83% and 55% (best formation). [ABSTRACT FROM AUTHOR]

Wind power-to-gas concepts have a high potential to sustainably cover the increasing demand for hydrogen as an energy carrier and raw material, as it has been shown in the past that there is an enormous potential in energy overproduction, which currently remains unused due to the shutdown of wind turbines. Thus, there is barely experience in maritime production, offshore storage, and transport of large quantities of liquid hydrogen (LH2) due to the developing market. Instead, tank designs refer to heavy standard onshore storage and transport applications with vacuum insulated double wall hulls made from austenitic stainless steel and comparatively high thermal diffusivity and conductivity. This reduces cost effectiveness due to inevitable boil-off and disregards some other requirements such as mechanical and cyclic strength and high corrosion resistance. Hence, new concepts for LH2 tanks are required for addressing these issues. Two innovative technical concepts from space travel and high-temperature applications were adopted, combined and qualified for use in the wind-power-to-gas scenario. The focus was particularly on the high requirements for transport weight, insulation and cryogenic durability. The first concept part consisted of the implementation of FRP (fiber-reinforced plastics)–steel hybrid tanks which have a high potential as a hull for LH2 tanks. However, these hybrid tanks are currently only used in the space sector. Questions still arise regarding interactions with coatings, production, material, temperature resilience and design for commercial use. Thermally sprayed thermal barrier coatings (TBC) in turn show promising potential for surfaces subject to high thermal and mechanical stress. However, the application is currently limited to use at high temperatures and needed to be extended to the cryogenic temperature range. The research on this second part of the concept thus focused on the validation of standard MCrAlY alloys and innovative (partially) amorphous metal coatings with regard to mechanical-technological and insulating properties in the low temperature range. This article gives an overview regarding the achieved results including manufacturing and measurements on a small tank demonstrator. [ABSTRACT FROM AUTHOR]

This paper seeks to assist in the surveying of listed properties and the considerations that may be taken when addressing whether to insulate solid flooring and, if so, how to go about it. The author seeks to address a variety of potential problems and opportunities that may be found when assessing the property and does not consider this paper to cover all eventualities. One of the main things the author is aware of is the merit of each property needing to be assessed as a unique and individual entity. In many cases, it may also be worth looking at areas within the property itself; different rooms will have different needs, uses and potentially differing existing flooring and will therefore need to be addressed on a room-by-room basis. As the author runs a company that specialises in limecrete flooring, she is aware of her own potential bias and the weighted information that she will provide in her own specialist field. Therefore, this paper does not aim to suggest a single answer approach to the question of insulating solid floors in listed buildings; however, more detail will be given with regard to an insulated limecrete flooring approach. The author does not hold any design liability, and any design ideas described in this paper are based upon her knowledge and experience in the field. In particular, when it comes to limecrete floor design, she is drawing on designs that her company has been given by their customers to work on and the opportunities this has given for consideration in this paper. [ABSTRACT FROM AUTHOR]

The largest influences on a building's cooling and heating load come from heat absorption and loss through building surfaces. Most of the heat gain is absorbed by a structure's roof. Applying insulation to building envelopes is an efficient approach to cut back on heating and cooling energy use as well as the damaging effects of the construction industry on the environment. As a result, it is extremely important to choose the right insulation material and determine the ideal insulation thickness. Eight diverse cities with a range of climatic variables that are spread over several Indian areas (geometric coordinates) are the starting point for this investigation. To overcome the constraints of the various climate typology representing the diverse climatic circumstances present in India, a generic method is proposed, considering the numerous climatic parameters for eight selected Indian locations. The subject of the project is the analysis of a composite insulation layer made from a combination of chosen seven insulating materials, each of which has a unique property. This building roof envelope is examined using ANSYS software and e-Quest building energy modeling. The results of simulations over the course of the whole year show a significant decrease in energy use and CO2 emissions. By altering the thickness of the created envelope, the annual energy need is decreased for each of the seven trials in the range of 30–90%. A decrease in heat flow results in sustainable buildings and a low-carbon future by lowering temperatures by 19 degrees and cutting greenhouse gas emissions by 90% to 96%. [ABSTRACT FROM AUTHOR]

This research aims to reduce electricity use and promote activities to reduce electricity use within the organisation through a case study from the PCB assembly department. It was found that the total annual electricity consumption is approximately 2,099,093 kWh/y. The amount of PCB production per time is 7 sheets, and the delay time to release PCB sheets is 15 s per sheet. Therefore, the researcher used the AHP techniques to identify the problems. The solution is to introduce innovative insulation wrapping that can help reduce heat radiation from the machine. From the experiment, it was found that after the improvement, the production number increased to 11 sheets, with a delay time of 10 s per sheet. Production increased by 33.3%, heat loss decreased by 53.5%. As a percentage per power dropped 51% and the percentage of the electricity cost was 70.1% the payback period was 1.69 years. [ABSTRACT FROM AUTHOR]

Purpose: The use of thermal insulations reduces the risk of hypothermia, therefore decreases the risk of death in trauma victims. The aim of the study was to assess whether thermal insulations cause artifacts, which may hinder the diagnosis of injuries, and how the used thermo-systems alter the radiation dose in polytrauma computed tomography. Methods: Computed tomography scans were made using the road accident victim body wrapped consecutively with 7 different covers. 14 injury areas were listed and evaluated by 22 radiologists. The radiation dose was measured using a dosimeter placed on the victim in the abdominal area. Results: No significant artifacts in any of the tested covers were observed. The presence of few minor artifacts did not hinder the assessment of injuries. Certain materials increased (up to 19,1%) and some decreased (up to -30,3%) the absorbed radiation dose. Conclusions: Thermal insulation systems tested in this study do not cause significant artifacts hindering assessment of injuries in CT scans. Concern for artifacts and increased radiation dose should not be a reason to remove patients' thermal insulation during performing trauma CT-scanning. [ABSTRACT FROM AUTHOR]

Copyright of Bearing is the property of Bearing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Herein, the cellulose aerogel (CellA) material was synthesized from bulk cellulose derived from corn stalks with poly(vinyl alcohol) (PVA) as the binding agent. In detail, the influence of precursor mass ratio on the physicochemical properties and adsorption capacity of CellA was thoroughly investigated, which illustrated the cellulose:PVA ratio of 15:1 as the suitable fabrication of cellulose aerogel, with favorable density, porosity, and characteristic behaviors. The surface modification for the prepared CellA was also carried out using stearic acid and polydimethylsiloxane, followed by a carbonization treatment. The obtained results revealed that the 500 °C-carbonization of the stearic acid-coated sample exhibited superior adsorption capacity of cooking oil (32.98 g/g) as well as a high hydrophobicity with a wetting angle of 131.7°. Besides, the sample also provided a relatively low thermal conductivity at 0.067–0.069 W/m K within a surveyed temperature range of 40–50 °C. Conclusively, the environmentally-inspired CellA material highlights an effective utilization of corn stalks—an abundant biomass source via a facile preparation effort as an alternative candidate for the adsorption of non-polar organic compounds and thermal insulation. [ABSTRACT FROM AUTHOR]

A popular belief for why polar bears have black skin is to increase solar heat gain from solar radiation that penetrates through a translucent fur layer made of unpigmented hollow hair. To examine the relative importance of skin color on solar heat gain, we measured thermal gradients, heat flux, and solar transmittance through a polar bear pelt under solar irradiation while thermally anchored to a temperature-controlled plate set to 33 °C. We found that for 60–70% of the dorsal region of the pelt where the fur layer is thickest, solar energy cannot reach the skin through the fur (solar transmittance ≤ 3.5 ± 0.2%) and therefore skin color does not meaningfully contribute to solar heat gain. In contrast, skin pigmentation was important in the remaining areas of the pelt that were covered with thinner fur. This information was used to select commercially available materials according to their solar optical properties to build biomimetic outdoor apparel with enhanced solar heat gain by a factor of 3 compared to standard outerwear constructions. [ABSTRACT FROM AUTHOR]

This study assesses the technical, economic, and environmental assessment of a developed improved cookstove (ICS) for domestic uses focusing on outperforming the traditional charcoal cookstove by improving technical performance, fuel economy, and environmental savings. A set of experiments were conducted to verify the performance of the ICS. The technical performance involved measuring the cooking time (tc), maximum cooking temperature (Tmax), fuel consumption (fcons), thermal efficiency (ηth), and cooling time (tcool). The economic assessment involved daily and annual fuel cost, and daily and annual fuel cost saving while environmental saving involved annual reduction of CO, CO2, NO, and NOx gases. The Tmax of the ICS reached 1273 K, reducing the tc by 18 mins, a drop of 43%. Furthermore, this reduced the fcons by approximately 50 g, around 30%. The ICS had an enhanced tcool of about 24.53 mins and attained ηth of 43.3%. In five tests, the ICS consumed about 596 g, which costs TZS 870 and TZS 317,550 per year. The reduction in consumption significantly reduces fuel costs by 29.83%. The results showed the ICS reduced the emission of CO, CO2, NO, and NOx concentrations by 258, 650, 2, and 2.5 ppm, respectively, compared to a traditional charcoal cookstove. [ABSTRACT FROM AUTHOR]

The widespread use of cellulose nanofiber (CNF)-based aerogels is hindered by their limited flame retardancy and mechanical properties. This study addresses these challenges by developing cellulose nanofiber/sodium alginate/fly ash (CNF/SA/FA) aerogel through a one-pot method, utilizing industrial waste fly ash (FA) as a reinforcing material. Various characterization and analytical techniques were employed to evaluate the properties of the CNF/SA/FA aerogel. The findings have revealed that resulting aerogel exhibited excellent thermal insulation performance, with a thermal conductivity of 0.485 W/(m·K), along with an impressive compressive strength of 88.4 kPa and favorable shape processability. Vertical combustion tests demonstrated a V-0 rating, indicating superior flame retardancy, and the aerogel achieved a remarkable 79.16% residual carbon, confirming their effective heat shielding capabilities. Notably, the incorporation of FA significantly enhanced both the thermal and mechanical properties of the composite aerogel, presenting a sustainable and effective solution to optimizing the properties of aerogel for thermal insulation.

We address a non-destructive testing of bitumen insulations. A new approach to its in situ monitoring is proposed. It is based on single impact microindentation. To describe the straining process of a bitumen coating, we analyzed Maxwell and Voigt rheological models. It is shown experimentally that Maxwell model suits well for this task. Temporal changes of the rigidity coefficient in the coating depending on the ambient temperature were measured. It has been established that microindentation-based method is effective for the assessment of the insulation aging. Thermal aging experiments and measurements were carried out to confirm the applicability of the proposed approach. [ABSTRACT FROM AUTHOR]

A popular belief for why polar bears have black skin is to increase solar heat gain from solar radiation that penetrates through a translucent fur layer made of unpigmented hollow hair. To examine the relative importance of skin color on solar heat gain, we measured thermal gradients, heat flux, and solar transmittance through a polar bear pelt under solar irradiation while thermally anchored to a temperature-controlled plate set to 33 °C. We found that for 60–70% of the dorsal region of the pelt where the fur layer is thickest, solar energy cannot reach the skin through the fur (solar transmittance ≤ 3.5 ± 0.2%) and therefore skin color does not meaningfully contribute to solar heat gain. In contrast, skin pigmentation was important in the remaining areas of the pelt that were covered with thinner fur. This information was used to select commercially available materials according to their solar optical properties to build biomimetic outdoor apparel with enhanced solar heat gain by a factor of 3 compared to standard outerwear constructions.

Abstract Electric machines form an essential part of a wide range of modern systems. When speed control is required, the use of pulse width modulation‐based inverters is generally the solution of choice. It is also usual to connect the machine to the inverter using a cable. The combination of these three elements produces the potential for voltages which exceed the dc link voltage to occur at the machine terminals. Methods for predicting the terminal voltage exist; however, these methods assume that the pulses applied to the system can be considered as isolated, discrete events. The authors highlight an issue with this assumption. When a switching event occurs, it will cause a voltage disturbance in the unswitched phases of the system due to the mutual coupling between the phases. If a second switching event occurs within a short time of this event the resultant voltage will interact with the previous switching event resulting in a higher terminal voltage than would be the case for an isolated event. This effect can be problematic for insulation design if it is not considered. This issue is demonstrated, with the worst‐case scenarios identified and potential methods of reducing terminal voltage being proposed.

RELEVANCE. The current technical condition of electrical networks at the moment is generally unsatisfactory with an average level of physical wear of about 60-70 %, therefore,the development of fundamentally new methods for assessing their technical condition is currently an urgent task. The methods of assessing the technical condition of electrical networks analyzed in the article are based to a greater extent on the subjective and insufficiently accurate method of expert assessments, which actually does not take into account the data of its technical diagnostics, as well as statistics of defects and failures. OBJECT. To develop a methodology for assessing the technical condition of electrical networks, which would be based on probabilistic models characterizing the physical processes occurring in electrical networks, as well as data from their technical diagnostics, statistics of defects and failures. METHODS. To assess the technical condition of electrical networks, a probabilistic assessment method was used. In this case, the methodology involves sequential determination of the probabilities of occurrence of selected groups of emergency modes, the probability of failure of a network element as a whole, as well as the probability of failure of an object and a group of objects of the power grid. RESULTS. Based on the research results, probabilistic models of failure of electrical networks were obtained, which, unlike the assessment methods discussed in the article, are based on data from technical diagnostics and inspections of electrical equipment. An example of the implementation of the developed methodology on real electrical network objects is given. CONCLUSION. The developed methodology allows for a more reasonable prioritization of technical impacts on electrical grid equipment, which will make it possible to replace or repair equipment that has actually exhausted its physical resource, which will reduce the frequency of emergency conditions and reduce damage from power supply interruptions.

In the last decade, growing efforts were made to replace crosslinked XLPE insulations with thermoplastic ones in high-voltage DC cables. The main reason for these development projects is the injection and trapping of charge carriers under DC conditions, leading to a field distribution within the insulation layer different from HVAC cables. Thermoplastic cable insulation is favorable in many respects, except for its thermal stability. So far, HDPE/LDPE and binary or ternary PP-based blends have been tried. The former offers a limited advantage in heat resistance, while the latter is too hard at high PP contents and loses thermomechanical properties at high elastomer contents. In this paper, the compatibility of binary polyolefin blends is first briefly reviewed; then, the cable-specific properties are presented together with examples taken from the literature. Deep trap formation, low conductivity, and optimum breakdown properties are observed in HDPE/LDPE blends under specific crystallization conditions where a fine-grained structure is formed. It results in a proper concentration of the traps, but these are not accumulated at the spherulite boundaries. Trap density and energy are also modulated by the relaxation processes. The future belongs to the PP-based blends, where several compatibilizing agents (copolymers, elastomers, in situ reactions) have been tried to find the balance between electrical, mechanical, and thermal properties. In these materials, again, fine, close to co-continuous structures should be achieved to reach the required properties, but the aromatic and polar comonomer content also contributes to the formation of deep traps in relatively uniform distribution. The PP phase must remain continuous to maintain the necessary thermomechanical properties above the Tg of the soft components.

Abstract Electric power provision for all the customers is not always possible for distribution companies. Some customers are interested in serving their load through renewable resources regarding the climate situation. Electrically off‐grid zero‐energy building is an applicable concept, in which the electrical energy provision of the buildings is isolated from the power supply infrastructures. This paper introduces a robust bi‐level programming model to create a cost‐effective off‐grid zero energy complex in Kish Island under risk management. The upper level of the planning is composed of two components, the passive design of buildings within the complex and the design of a stand‐alone energy system. The passive design as an energy‐saving tool includes the selection of insulation material for building external walls and finding the optimum thickness. Also, the stand‐alone energy system design denotes the sizing of diesel generator, photovoltaic, and battery energy storage as the distributed energy resources. The lower‐level problem optimally handles the annual scheduling of these resources to meet the complex demand under the impact of passive cooling. The Karush–Kuhn–Tucker condition method is used to solve this bi‐level planning problem. Furthermore, the battery degradation is concerned via the throughput model to consider the replacement cost of the problem.

Abstract Assessing the insulation condition of oil‐impregnated paper (OIP) bushings is necessary to guarantee the safe operation of power transformers. Moisture is the main threat to the insulation of OIP bushings. Therefore, accurately estimating their moisture value is crucial to keep power systems running smoothly. However, it has been suggested that the ageing status of OIP bushings should be considered while assessing the moisture. Dielectric frequency‐domain spectroscopy (FDS) has been extensively employed for assessing insulation condition of OIP insulations due to its benefits. A new approach was proposed to assess the insulation condition of OIP bushings using FDS results. Various OIP samples with various moisture levels and degrees of polymerisation (DP) were selected. The extended Debye model (EDM) parameters related to each sample were calculated using their tanδ − f curve. A time constant database (TCD) was created using the obtained time constants of EDM, which includes the dominant time constant and time constant related to the R0 – C0 branch, and their corresponding insulation condition. Then, a method was introduced based on the created TCD to estimate the insulation condition of OIP bushings. The results showed that the average relative error of moisture and DP estimation is 8.33% and 6.32%, respectively.

RELEVANCE. The length and complexity of the geography of medium voltage cable lines is at a high level. Such lines extend underground, on supports in the air. In order to constantly maintain the reliability of city power supply at a high level, any interruptions and accidents should be promptly corrected.TARGET. The main goal of the work is to develop the theory of medium voltage CL research, to practically and theoretically substantiate the search for the most convenient and effective installation for CL diagnostics, to study and develop possible modifications of CL diagnostic installations.METHODS. A variant of CL diagnostics based on the CPDA-60 installation is proposed, which makes it possible to find and localize the places where defects occur in the insulation based on the measurement and analysis of partial discharges (PD). Suitable for insulation monitoring in all types of high voltage cables. The CPDA installation can be used when testing new cable lines being put into operation, and to analyze the condition of old cables in operation.RESULTS. Cable lines require an integrated approach to diagnostics and monitoring, since the reliability of modern authentication systems for the generation and distribution of electricity is largely determined by the electrical reliability of electrical equipment. Technical diagnostics of equipment is a key link, the quality of which determines the efficiency of the processes of organizing production activities, strategic planning and renovation of electric grid assets.CONCLUSION. The study and analysis of the presented data and research allows us to form a conclusion regarding the method of measuring and localizing partial discharges (PD) in power cable lines (CL) using the Online Wire Testing System (OWTS) diagnostic system. The OWTS system allows real-time measurements without interrupting cable lines, making it especially valuable to the energy industry. Thanks to the introduction of advanced technologies and signal processing algorithms, the method has high accuracy and sensitivity to minimal manifestations of private discharges, which allows not only to detect, but also to accurately localize the location of defects in the insulation. The use of this method can significantly increase the service life of power cables, reduce the likelihood of sudden accidents and, as a result, reduce the cost of repair and maintenance of electrical power equipment. Ultimately, improvements in diagnostic and monitoring techniques, including the method of measuring and localizing PD in power lines using OWTS, represent a significant step towards improving the reliability and safety of electrical power systems. This will not only reduce operating costs, but also ensure uninterrupted and high-quality power supply to consumers.

Biobased foams have the potential to serve as eco-friendly alternatives to petroleum-based foams, provided they achieve comparable thermomechanical and physical properties. We propose a facile approach to fabricate eco-friendly cellulose nanofibril (CNF)-reinforced thermomechanical pulp (TMP) fiber-based foams via an oven-drying process with thermal conductivity as low as 0.036 W/(m·K) at a 34.4 kg/m3 density. Acrodur®, iron chloride (FeCl3), and cationic polyacrylamide (CPAM) were used to improve the foam properties. Acrodur® did not have any significant effect on the foamability and density of the foams. Mechanical, thermal, cushioning, and water absorption properties of the foams were dependent on the density and interactions of the additives with the fibers. Due to their high density, foams with CPAM and FeCl3 at a 1% additive dosage had significantly higher compressive properties at the expense of slightly higher thermal conductivity. There was slight increase in compressive properties with the addition of Acrodur®. All additives improved the water stability of the foams, rendering them stable even after 24 h of water absorption. [ABSTRACT FROM AUTHOR]

Local buckling (wrinkling) is very common in metal-faced insulating sandwich panels (MFISPs) due to the small thickness of their face sheets. In some cases, wrinkling leads to sudden failures, while in others it leads to degradation of the overall stiffness and can decrease the failure load. A simplified finite-element modelling approach is presented to estimate the local buckling pressure of such panels. In the proposed approach, only the face sheet under compression is modelled, thus avoiding the need to perform a full three-dimensional (3D) structural analysis. The working assumption is that the relative deflection of the buckled face against the face under tension (unbuckled face) can be modelled using a two-parameter elastic foundation approach. The elastic foundation is simulated by closely spaced horizontal and vertical springs that model the rigidities of the foam core. Two models are used to determine the elastic foundation properties. The simplified approach was validated through comparisons with 3D analyses of full sandwich panels and available experimental results. It was found that the proposed approach can be applied to various types of MFISPs (flat or heavily profiled) with a variety of foam cores and face sheet thicknesses. [ABSTRACT FROM AUTHOR]

Copyright of Automobile Technology & Material is the property of Automobile Technology & Material Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)