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The reliability of thermal regulation systems is crucial for ensuring the stability of condensed-mode gas-phase fluidized bed reactors (FBRs) used in the production of linear low-density polyethylene (LLDPE). However, studies reporting on the practical industrial control engineering of such reactors relying on thermal equilibrium mechanisms are scarce. This study presents a thorough analysis of a hot thermoregulating water (TRW) valve-jamming incident and interprets the related phenomena and parameter changes. The effect of the catalyst activity and variations in the liquid-phase quantities on the TRW valve action are investigated in depth, and a general explanation is provided by analyzing typical distributed control system data trends and proven deductive reasoning. Results indicate that the polymerization stability is maintained by two thermal pathways. The first pathway is related to the latent (condensate)/sensible heat (gas) extraction and polymerization heat of the materials, and the second is associated with the TRW system, specifically the cold and hot TRW branches. These pathways exhibited synergistic bidirectional effects. Finally, a series of innovative measures are proposed for internal and external operations to fully prevent and respond to TRW valve malfunctions and maintain overall polymerization stability. This study enhances the dependability of linear low-density polyethylene production through advanced process optimization utilizing the Unipol prototype and offers perspectives on system engineering for polyethylene production processes. [ABSTRACT FROM AUTHOR]

Daylighting design is not only dimensioning glazed surfaces to provide sufficient natural light to an occupied space but also a method of analyzing how this can be achieved without unwanted effects, such as gains and losses of heat, glare, and variations in daylighting intensity at various indoor distances and levels. The case study presented in this paper highlights the energy consumed due to a group of windows with a large glazed area in an existing building located in a temperate continental climate area. The energy consumption results from supplementary artificial lighting required to maintain adequate illumination for indoor activities and to counterbalance heat loss during colder periods are evaluated. The analysis performed by modifying the glazed surface led to the identification of an optimum value of window dimensions for minimum energy consumption. The results of the case study highlight the fact that the evolution of the total energy consumption, evaluated as the sum of the energy consumption due to additional heating/cooling and the artificial lighting required to compensate for the reduction in natural light, is strongly influenced by the dimensions of the glazed surfaces, as well as the minimum level of lighting imposed by the regime of activities carried out in the building. Thus, the outcomes obtained in the research show that at lighting values below 500 lx, the total energy consumption is directly proportional to the glazed surface. From values of 500 lx for the illuminance level, the total energy consumption drops from 2730 kWh/year for a window height of 230 cm to 2399 kWh/year for a height of 110 cm, after which it starts to rise again, reaching a value of 2786 kWh/year for a height of 30 cm. This phenomenon is also found at values higher than 500 lx; accordingly, for an imposed lighting of 1000 lx, the minimum total consumption is identified at a window height of 150 cm. The case study presented in this paper clearly highlights a complex relationship between the height of the glazed surface and the energy consumption required to compensate for heating or cooling and the reduction in natural lighting. Lower window heights reduce heat loss or gain but also correspondingly increase the energy consumption of artificial lighting. [ABSTRACT FROM AUTHOR]

Shallow geothermal heat has the characteristics of wide distribution and huge reserves. However, for northern rural buildings, the heating load in winter is much greater than the cooling load in summer, and thermal imbalance of the soil is prone to occur. This paper takes rural residences in southern Hebei as an example and designs a solar-assisted shallow geothermal energy system. Compared with the original shallow ground-source heat pump system, the indoor and outdoor temperature differences of the target building were first analyzed. Second, the changes in the soil temperature field and the differences in the supply and return water temperature were monitored. Finally, the initial investment and operating costs of the assisted system are analyzed. The results show that the average ground temperature field increases significantly in winter. Through the alternate operation of solar energy and ground-source heat pumps, heat extraction from the ground is reduced, and the imbalance cycle of heat extraction in winter and heat removal in summer is shortened. It alleviates the imbalance of the cold and heat loads for soil throughout the year. The inlet and outlet water temperature and heat exchange efficiency of the buried pipes have been significantly improved. The energy efficiency ratio of the system using the assisted system has increased from 3.40 in 2020 to 4.17, an increase of 0.77. The optimal ratio of the solar- assisted shallow geothermal energy system is a 12.80 m2 solar heat-collection area and one buried hole. The winter heating operating cost of the solar-assisted shallow geothermal energy system is 18.86 CNY/m2. It can save 37% of the annual operating costs of heating, cooling, and hot water compared to a single ground-source heat pump system and 40%–45% compared to traditional heating and cooling modes. [ABSTRACT FROM AUTHOR]

Thermal balance is paramount to human comfort and safety. To better understand the effects of the material and environment, a modified sweating-hot-plate test was used to incorporate environmental parameters such as the ventilation and microclimate thickness. It was found that at wind speeds ≤ 0.5 m/s, the environment has the most significant effect on the insulation. However, at an increased wind speed (1.3 m/s), the construction of the material has a large influence on the insulation of the system. At a low metabolic rate, the heat storage can be compensated for through dry heat loss; but, at a higher metabolic rate, substantial differences in the sweating rates are required based on the material and environment. The various aspects of the environment wind speed, microclimate thickness, and ventilation are crucial, but, in certain combinations, the material can have a significant impact as well. [ABSTRACT FROM AUTHOR]

This article presents the results of model studies of a photovoltaic thermal battery (PVTB) based on a thin-film cadmium telluride (CdTe) module depending on the influence of environmental parameters: solar radiation, air temperature, wind speed on the heating temperature of PVTB elements. A heat transfer scheme in PVTB elements, a mathematical model of heat balance processes and a program in the algorithmic Python language for calculating thermal and energy parameters were developed. The equations of thermal balances were solved in the static state of the installation using the numerical method of Gauss-Seidel iterations. To validate the model, the calculated simulation results were compared with experimental data. A comparison of the values of the corresponding parameters is presented in graphical images. The adequacy of the model was verified by the method of "assessment of agreement and standard deviation". The following values of RMSE and determination coefficients were calculated for the parameters, respectively, for the temperature of the photovoltaic cell, liquid and electrical efficiency R2=0.88, for thermal efficiency and power R2=0.99, for power RMSE=2.56 W, RMSE deviation 5.72%. Using the SolidWorks Flow Simulation software was performed CFD PVTB modeling, simulating the temperature dynamics of glass, PV and absorber depending on environmental factors and the temperature dynamics of cooling water circulating in a copper heat exchanger. The values of the parameters obtained from CFD modeling correspond to the experimental data. The considered modeling methods make it possible to calculate the thermal and energy parameters of PVT installations at the engineering design stage.

The work describes the possibility of using a conducting fluid model (single-fluid model) to analyze physical phenomena observed in the inhomogeneous gas discharge plasma. A technique for calculation of the heat fluxes and temperature fields in a discharge in a cylindrical glass tube with metal sections is proposed. The presence of metal sections leads to a change in the thermal balance in the plasma volume. Specific calculations have been carried out for conditions with significantly different thermal conductivity coefficients of gases (argon and helium) and metals (steel and copper). Two cases of the discharge state—diffuse and constricted—are considered. Spatial distributions of heat sources, temperature fields and heat fluxes depending on the gas type, and discharge tube configuration are presented. The considered discharge configuration and the proposed calculation method can be useful for practical applications, for example, in laser physics. [ABSTRACT FROM AUTHOR]

Efficient operation of terminal devices containing cryogenic current leads connecting the sources of power generation and consumption with a cable based on high-temperature superconductors ensures reliable operation of the entire power supply system. A method for calculating the temperature at the junction of a superconductor with the resistive part of a current lead when the current changes in the case of cooling the contact section with single-phase liquid nitrogen or gaseous helium is proposed. An analysis of heat removal from the contact area under conditions of free and forced convection has been performed, and the ratios between the heat transfer coefficients of liquid nitrogen and gaseous helium in the range of temperature and pressure values corresponding to the operating parameters of existing HTS cables have been determined. It is shown that the main influence on the thermal balance of the resistive and contact sections of the current lead is exerted by the temperature, and not by the heat transfer coefficient of the cryoagent used. [ABSTRACT FROM AUTHOR]

Syngas from biomass gasification represents an interesting alternative to traditional fuels in spark-ignition (SI) internal combustion engines (ICEs). The presence of inert species in the syngas (H2O, CO2, N2) reduces the amount of primary energy that can be exploited through combustion, but it can also have an insulating effect on the cylinder walls, increasing the average combustion temperature and reducing heat losses. A predictive numerical approach is here proposed to derive hints related to the possible optimization of the syngas-engine coupling and to balance at the best the opposite effects taking place during the energy conversion process. A three-dimensional (3D) computational fluid dynamics (CFD) model is developed, based on a detailed kinetic mechanism of combustion, to reproduce the combustion cycle of a cogenerative engine fueled by syngas deriving from the gasification of different feedstocks. Numerical results are validated with respect to experimental measurements made under real operation. Main findings reveal how heat transfer mainly occurs through the chamber and piston walls up to 50° after top dead center (ATDC), with the presence of inert gases (mostly N2) which decrease the syngas lower calorific value but have a beneficial insulating effect along the liner walls. However, the overall conversion efficiency of the biomass-to-ICE chain is mostly favored by high-quality syngas from biomasses with low-ashes content. [ABSTRACT FROM AUTHOR]

This study presents a comprehensive analysis of an Alkaline Water Electrolysis System (AWES) for hydrogen production, focusing on thermal balance, operating conditions, efficiency, and lifecycle cost. A thermal balance model was developed and further refined using machine learning techniques based on experimental data, to accurately calculate electrolysis power, cooling requirements, and temperature maintenance, enabling cost-effective operation. This study provides insights for optimizing AWES performance and economic feasibility in hydrogen production. Selecting appropriate operating conditions considering current density, inlet temperature, and electricity price is crucial. Implementing these optimizations improves energy efficiency, reduces lifecycle hydrogen production costs, and enables integration with renewable energy systems. • An overall understanding of the alkaline electrolyzer operating conditions and performance is provided. • A universal modeling method based on thermal-balance model for operation optimization is proposed. • Machine learning approach is applied to calibrate model accuracy. • Mapping of hydrogen production efficiency and cost effectiveness is produced for full operation range. [ABSTRACT FROM AUTHOR]

The paper presents a one-dimensional aeronomic model of hydrogen–helium upper atmospheres of hot giant exoplanets based on the approximation of single-fluid multicomponent hydrodynamics. Chemical reactions and heating–cooling processes are taken into account. Typical cases of a hot Jupiter and a warm Neptune are considered as an example of the application of the model. Calculations were carried out for various values of the gas pressure at the photometric radius of a planet. In the solutions obtained, the transonic planetary wind is formed, which leads to a hydrodynamic outflow of the atmosphere with mass loss rates of about 1010 and 109 g/s for a hot Jupiter and a warm Neptune, respectively. At the same time, the outer layers of the atmosphere of a hot Jupiter become completely ionized, while the atmosphere of a warm Neptune mainly consists of neutral gas. In some variants of the hot Jupiter model, instability develops in the deep layers of the atmosphere, which may result in the formation of a specific cloud layer. [ABSTRACT FROM AUTHOR]

Daylighting design is not only dimensioning glazed surfaces to provide sufficient natural light to an occupied space but also a method of analyzing how this can be achieved without unwanted effects, such as gains and losses of heat, glare, and variations in daylighting intensity at various indoor distances and levels. The case study presented in this paper highlights the energy consumed due to a group of windows with a large glazed area in an existing building located in a temperate continental climate area. The energy consumption results from supplementary artificial lighting required to maintain adequate illumination for indoor activities and to counterbalance heat loss during colder periods are evaluated. The analysis performed by modifying the glazed surface led to the identification of an optimum value of window dimensions for minimum energy consumption. The results of the case study highlight the fact that the evolution of the total energy consumption, evaluated as the sum of the energy consumption due to additional heating/cooling and the artificial lighting required to compensate for the reduction in natural light, is strongly influenced by the dimensions of the glazed surfaces, as well as the minimum level of lighting imposed by the regime of activities carried out in the building. Thus, the outcomes obtained in the research show that at lighting values below 500 lx, the total energy consumption is directly proportional to the glazed surface. From values of 500 lx for the illuminance level, the total energy consumption drops from 2730 kWh/year for a window height of 230 cm to 2399 kWh/year for a height of 110 cm, after which it starts to rise again, reaching a value of 2786 kWh/year for a height of 30 cm. This phenomenon is also found at values higher than 500 lx; accordingly, for an imposed lighting of 1000 lx, the minimum total consumption is identified at a window height of 150 cm. The case study presented in this paper clearly highlights a complex relationship between the height of the glazed surface and the energy consumption required to compensate for heating or cooling and the reduction in natural lighting. Lower window heights reduce heat loss or gain but also correspondingly increase the energy consumption of artificial lighting.

Thermal balance is paramount to human comfort and safety. To better understand the effects of the material and environment, a modified sweating-hot-plate test was used to incorporate environmental parameters such as the ventilation and microclimate thickness. It was found that at wind speeds ≤ 0.5 m/s, the environment has the most significant effect on the insulation. However, at an increased wind speed (1.3 m/s), the construction of the material has a large influence on the insulation of the system. At a low metabolic rate, the heat storage can be compensated for through dry heat loss; but, at a higher metabolic rate, substantial differences in the sweating rates are required based on the material and environment. The various aspects of the environment wind speed, microclimate thickness, and ventilation are crucial, but, in certain combinations, the material can have a significant impact as well.

Syngas from biomass gasification represents an interesting alternative to traditional fuels in spark-ignition (SI) internal combustion engines (ICEs). The presence of inert species in the syngas (H2O, CO2, N2) reduces the amount of primary energy that can be exploited through combustion, but it can also have an insulating effect on the cylinder walls, increasing the average combustion temperature and reducing heat losses. A predictive numerical approach is here proposed to derive hints related to the possible optimization of the syngas-engine coupling and to balance at the best the opposite effects taking place during the energy conversion process. A three-dimensional (3D) computational fluid dynamics (CFD) model is developed, based on a detailed kinetic mechanism of combustion, to reproduce the combustion cycle of a cogenerative engine fueled by syngas deriving from the gasification of different feedstocks. Numerical results are validated with respect to experimental measurements made under real operation. Main findings reveal how heat transfer mainly occurs through the chamber and piston walls up to 50° after top dead center (ATDC), with the presence of inert gases (mostly N2) which decrease the syngas lower calorific value but have a beneficial insulating effect along the liner walls. However, the overall conversion efficiency of the biomass-to-ICE chain is mostly favored by high-quality syngas from biomasses with low-ashes content.

The dynamic thermal rating (DTR) system can safely determine the thermal limits of power components on the basis of environmental conditions. Studies have shown that the DTR system can provide ratings that are higher than the traditional static thermal rating (STR) 80% to 90% of the time; 50% of the time, DTR is 15% to 30% higher than STR. Hence, the benefits and applications of the DTR system have been widely investigated and reported in various review papers. However, available reviews of the DTR system focused on transmission lines and networks only, ignoring the thermal limits of the transformer and distribution cable, which could form a thermal bottleneck. Moreover, these review articles cover only a few research themes, and many important research topics are left undiscussed. Therefore, these reviews cannot provide sufficiently diverse research on the DTR system. These drawbacks are addressed in this review article, which covers 176 notable research articles related to the DTR system obtained from three major databases, namely, IEEE, Elsevier, and Wiley. The collected articles are categorized based on their focus (e.g., distribution networks, transmission networks, and transformers) and then further classified into small groups on the basis of their research themes. Such an approach provides prospective researchers of the DTR system a one-stop summary of all previous studies.

The composition of the human body can be considered as a machine, as it does not move without fuel or energy. The human being requires energy in order to move, exercise his activity and survive, and human energy and health may be closely linked to the elements of the climate more than any other element of the natural environment. Studies have proven that the physiological functions of the human body respond to atmospheric changes, and achieving thermal balance through choosing the quantity and type of food or clothing, weight, age and the emergence and spread of some diseases also reflect the impact of environmental conditions on them. This paper attempts to clarify those relationships between thermal balance in the human body and between his physiological comfort.

Simple Summary: Water scarcity is a relevant issue in a scenario of climate change not only for animal production but also for many regular human activities. Thus, an adequate estimation of its demand is of high importance due to the high requirement for animal protein worldwide forecasted for the next decades. This study highlights that pen surface temperature can be used to predict daily water intake and tympanic temperature in feedlot steers. Commercial feedlot producers can estimate their water requirements under scenarios of heat stress with a simple tool, contributing to keeping sustainable production systems. Adequate estimation of water demand in cattle production feed yards is of high importance, especially due to reduced water availability because of changes in rain precipitation patterns and amounts. The pen surface in feed yards receives and reflects solar radiation, affecting along with other factors the microclimate to which cattle are exposed. This study aimed to describe the relationship between the pen surface temperature with the daily water intake and the tympanic temperature of finishing steers. Climate variables, including solar radiation, air temperature, relative humidity, and wind speed plus pen surface temperature and soil temperature at 10.2 cm depth were recorded. Data were collected from a weather station located in the feedlot in Concord NE, whereas daily water intake was estimated from a set of experimental pens sharing a waterer in two adjacent pens. Simple and polynomial linear regressions were assessed from data collected in different experiments conducted from 2003 to 2006. Two models to predict daily water intake were developed for finishing steers using the pen surface temperature as the predictor variable. The first one included data for the period May-October (overall model) and the second one for the summer period (June-August). The best fit for the overall model was a quadratic fit (r2 = 0.86), whereas the best-fit model for the summer model was the cubic (r2 = 0.72). Subsequently, both models were validated with data from an independent experiment conducted in the summer of 2007 in the same facilities. Both models tended to slightly overestimate daily water intake when they were validated (14.6% and 12.6%, respectively). For tympanic temperature, the best-fit model was linear, explaining 76% of the observed variability. When the dataset was split into night-time and daytime the best-fit model for the night period was a quadratic one and a linear one for the daytime, both improving the explanation of the variability observed. In conclusion, pen surface temperature can be used to predict both daily water intake and tympanic temperature in feedlot steers without access to shade. [ABSTRACT FROM AUTHOR]

The optimal process parameters of a gas-cleaning plant used to achieve and exceed its design efficiency are presented. The optimization conditions for the process parameters are determined. A situation schematic of static pressure (vacuum) measured at the design process parameters of the gas-cleaning system in the circuit of gas flues and process units is presented. One of the main causes of unstable operation of "dry" gas-cleaning systems is the lack of data on optimal process parameters. Such situations include changes in the properties of supplied alumina, gas-distribution balance, emergency shutdowns of one or more cleaning modules, etc. The results of study and testing of optimal gas cleaning parameters at one of the Russian aluminum plants under various operating conditions of gas-cleaning systems to ensure stable environmental performance of aluminum production are discussed. The case of emergency shutdown of two or more gas-cleaning modules is additionally examined. The test results show that when two or more modules fail or are shut down, the cleaning efficiency is not achieved when removing gaseous fluorine. Therefore, in such situations, it is necessary to increase the amount of fed alumina to 7.5 t/h and to increase the recycle rate to 3. [ABSTRACT FROM AUTHOR]

The temperature at which lubricant is supplied to the film on a fluid film fixed pad thrust bearing in a centrifugal or screw compressor is investigated. Sm2Px3Txτ software is employed for the calculations; this software implements a periodic thermoelastohydrodynamic model of bearing operation. The thermal balance of the bearing is described. The maximum temperature of the lubricant film and boundary layer, the power loss, and the carrying capacity are investigated as a function of the temperature of the incoming lubricant and the working gap. [ABSTRACT FROM AUTHOR]

Hyperactive comets have attracted attention due to their high water production rate with an unclear mechanism, though some hypotheses have been proposed to explain it. Based on the thermal theories of the comet nuclei, this paper studied a comet surface thermal model considering the sublimation of H2O. In this paper, a method for solving the sublimation rate of water ice by infrared spectroscopy is proposed. The method adopts the assumption of subpixel temperature nonuniformity on the comet nucleus surface and uses the numerical solution of the Fredholm equation. We use the HRI‐IR spectrum (1.05–4.8 μm) data by EPOXI to analyze the pixel‐by‐pixel water sublimation rate of hyperactive comet 103P/Hartley 2. The results show that sublimation exists in most areas of the surface with or without surface roughness, and most of the water production rate (70%–90%) may come from the comet nucleus when Gauss random surface roughness is adopted. According to the sublimation law, it is estimated that the sublimation temperature of water ice on 103P is above 180 K. If the dust‐to‐ice volume ratio is 3:1, the sublimation temperature is about 200–210 K, which indicates that the water ice may sublimate underneath. This may explain why exposed water ice on the surface can hardly be observed while the active fraction of this comet is up to 100%. Plain Language Summary: Extremely active comets, known as hyperactive comets, release water at very high rates, although observations indicate that they have little exposed water ice on their surfaces. We found a significant energy deficit in the comet surface spectroscopic data, suggesting that the sublimation of water ice may be prevalent in the layers just below the nucleus surface. The sublimation of these water ices may have provided an appreciable water production rate by hyperactive comets. Key Points: The sublimation of the water ice on the comet nucleus absorbs energy, which significantly reduces the infrared radiation on the surfaceThe high water production rate of hyperactive comets may be due to the sublimation of water ice in the surface layer of the comet nucleusThe solution of the Fredholm equation is proved effective to solve the surface temperature distribution based on the observed spectrum [ABSTRACT FROM AUTHOR]

Generally, the accuracy stability of a precision motorized spindle unit is influenced by its structural thermal balance behaviors (power matching degree of spindle structural heat generation–dissipations). For the accurate analysis of this spindle heat transfer behaviors based on temperature detections, this paper describes a method constructed with the numerical simulation technology and a proposed genetic algorithm-extreme learning machine (GA-ELM) algorithm. Firstly, the heat–fluid–solid coupling FE transient model is established to simulate spindle thermal behaviors, determinations of its thermal loads/boundary conditions are initially based on empirical calculations. Secondly, according to spindle temperature detections, these initial values are applied to thermal simulations and corrected by GA to make simulated spindle temperatures gradually approach detections. Specially, ELM is adopted to estimate the functional relationships from the parent population to the child population generated by genetic operators with increasing fitness values, and the trained ELM model is utilized to ensure the GA faster convergence. Eventually, based on the corrected thermal load/boundary condition values and simulation results, the time-varying power matching conditions of spindle structural heat generation–dissipation are analyzed. This study provides a theoretical basis for the optimization and promotion of spindle structural design and coolant control strategy. [ABSTRACT FROM AUTHOR]

In district heating systems (DHS), periodic heat supply-demand mismatches (HSDM) exacerbate issues such as thermal imbalance and hydraulic instability. To mitigate these issues, this paper proposes a supply water temperature correction strategy for heating stations that considers building's thermal characteristics. Firstly, buildings are classified into energy-saving levels based on comprehensive thermal characteristic Bc and heat load index. Secondly, simulation models are developed for buildings with different thermal characteristics, and response of indoor temperature to supply-demand mismatch rates was analyzed. Then, after determining the regulation sequence and supply water temperature of heating stations, a balanced control strategy is formulated for HSDM conditions. Finally, the proposed strategy was applied to a practical combined heat and power system (CHPS) in severe cold regions. The results showed that the studied heating stations were classified into 4 types. After regulation of both insufficient and excessive heating conditions, the indoor temperature guarantee rate increased by over 20 %; the ranges of thermal imbalance degree and hydraulic imbalance degree were reduced by more than 0.09 and 0.22, respectively; the SD of supply water pressure and supply-return pressure difference were reduced by over 0.17 and 0.11, respectively. The strategy provides a reference for global balanced control of DHS under similar HSDM conditions. • A balance control strategy for DHS under HSDM conditions. • The strategy integrates the buildings' thermal characteristics. • Heating stations are classified into 4 types based on building Bc and heat load index. • A fast and feasible method for adjusting water supply temperature to mitigate HSDM. • The thermal balance and hydraulic stability have been improved after regulation. [ABSTRACT FROM AUTHOR]

Abstract The objective of this work was to determine how different types of gait affect the physiological and thermographic responses of Pantaneiro horses (Equus ferus caballus) subjected to field conditions under high environmental temperatures. Ten horses were evaluated in a double 5x5 Latin square experimental design, with five gait types: walk, trot, extended trot, gallop, and extended gallop. The following physiological measures were determined immediately after exercise: heart and respiratory rates, blood lactate content, and rectal temperature. Body surface temperatures were evaluated using an infrared camera. The walk, trot, and extended trot were the most adequate gaits for Pantaneiro horses to maintain thermoregulation within the physiological norms under conditions with a high air temperature. The temperatures obtained in the eye and elbow regions show the best predictive capacity for physiological parameters.

The article analyzes the issues of formation of probabilistic-statistical worldview in students studying quantum physics chapter of academic lyceum of physics. In academic lyceums, there is little time devoted to the subject of quantum physics, the content of the topics is not well covered, in the analysis of the topic, the radiation laws of the absolute black body have a probabilistic character, and in the process of studying this topic, the introduction of probabilistic concepts based on Planck's formula and the study of radiation laws, the content of the subject - The ability of the extraction and enrichment to meet the requirements of the principle of consistency has been studied and discussed. [ABSTRACT FROM AUTHOR]

Three-dimensional network-on-chip (NoC) is the primary interconnection method for 3D-stacked multicore processors due to their excellent scalability and interconnect flexibility. With the support of 3D NoC, 3D non-uniform cache architecture (NUCA) is commonly used to organize the last-level cache (LLC) due to its high capacity and fast access latency. However, owing to the layered structure that leads to longer heat dissipation paths and variable inter-layer cooling efficiency, 3D NoC experiences a severe thermal problem that has a big impact on the reliability and performance of the chip. In traditional memory-to-LLC mapping in 3D NUCA, the traffic load in each node is inconsistent with its heat dissipation capability, causing thermal hotspots. To solve the above problem, we propose a temperature-balanced NUCA mapping mechanism named TB-NUCA. First, the Bayesian optimization algorithm is used to calculate the probability distribution of cache blocks in each node in order to equalize the node temperature. Secondly, the structure of TB-NUCA is designed. Finally, comparative experiments were conducted under random, transpose-2, and shuffle traffic patterns. The experimental results reveal that, compared with the classical NUCA mapping mechanism (S-NUCA), TB-NUCA can increase the mean-time-to-failure (MTTF) of routers by up to 28.13% while reducing the maximum temperature, average temperature, and standard deviation of temperature by a maximum of 4.92%, 4.48%, and 20.46%, respectively. [ABSTRACT FROM AUTHOR]

Cement production is one of the most energy-consuming industries in the world, and the grate cooler plays a vital role in cement quality and energy recovery. In this paper, a mass and thermal balance experiment of a 5000 t/d cement plant in China is performed to obtain the operating parameters and energy distribution. The experimental results indicate fuel combustion is the main source of energy due to the generation of about 74.8% of the total heat input energy of the system. In the output energy, the formation heat of clinker and the sensible heat of air account for 39.8% and 37.7%, respectively. The proportion of surface heat dissipation is not high, only 6.9%, mainly concentrated in the preheater and kiln shell. Furthermore, based on the experimental parameters, a novel two-equation energy model of the grate cooler is constructed, which shows higher accuracy due to the introduction of thermal dispersion and thermal radiation. The effects of different operating parameters on the heat transfer and energy recovery efficiency of the grate cooler are analyzed. On the premise of ensuring the quality and output of cement, the grate bed speed of 0.01 m/s is considered optimal.

Biological rules describe general morphological, structural and genetic patterns within and across species. Within these, ecogeographical rules correlate phenotypic variation of organisms with biogeography. The latter have been developed over the last 150 years, and recently have gained renewed attention due to climate change, as researchers try to predict how species will respond to different environmental conditions based on certain phenotypic features. However, there is no agreement whether such rules hold true in our rapidly changing world. Among the ecogeographical rules, six have focused on the contributions of the coloured integument and body size to the thermal balance of individuals. They are therefore particularly relevant for predicting how species' phenotypes will respond to future climatic scenarios. Here, we provide an overview and discuss these ecogeographical rules, particularly in light of thermoregulation, and probe the extent to which these rules apply, and the taxonomic levels at which they are relevant. The predictions of these rules often contradict each other, and indeed we argue that use of the word 'rule' itself hinders their careful investigation. Moreover, disrupted climate patterns and global warming alter the environmental conditions under which these rules were once formulated. Thus, these rules may be outdated in our current rapidly changing environment. We conclude by proposing a revised concept of ecogeographical rules, where the micro‐environment should have a stronger influence on the phenotype of organisms than its geographical location, and we suggest precautions researchers should take when testing them. [ABSTRACT FROM AUTHOR]

Gypsum-bearing waste has value for the production of construction materials, resource extraction, and agriculture. However, its unstable composition prevents the development of a single comprehensive approach to processing such waste. The design of a drying drum is discussed for a line capable of comprehensive processing of gypsum-bearing waste from various industrial enterprises. [ABSTRACT FROM AUTHOR]

Religious art, expressed through the architecture and painting of churches, is subject to the action of time, requiring preservation of the architectural and artistic heritage throughout their existence by providing adequate microclimate parameters.

Air-cooled proton exchange membrane fuel cells (PEMFCs) have the advantages of simple structure, low parasitic power, and flexible application scenarios. However, it is difficult to warm up the stack under subzero temperatures because excessive air is used as the cooling medium. In this study, the thermal balance inside an air-cooled PEMFC stack during cold start was theoretically analyzed to explore the relationship between the heating power and ambient temperature. Subsequently, the cold-start performance was tested in a climatic chamber. The results showed that the combination of endplate heating and gas heating is a feasible cold-start measure. The theoretical analysis indicated that only 14 % of the stack rated power for preheating can promote a successful cold start at −30 °C, which has also been validated in the ensuing tests. The test results showed that the temperature uniformity and the cell voltage consistency deteriorate as the ambient temperature decreases, while these two indicators can be improved by increasing the gas heating power. As the ambient temperature decreases, the heating power may become too high, resulting in poor cold-start performance. Therefore, if an air-cooled stack is to be started at extreme low temperatures, further research is needed in terms of flow fields and materials. [ABSTRACT FROM AUTHOR]

The cutting of special stainless steels for thrust bearings is studied experimentally. The steels considered are 95Х18-Ш, 110Х18-ШД, 75ХГСФ, and 40ХНЮ-ВИ. The formation of the surface roughness and the distortion of the part after machining are described. The influence of the cutting parameters on the cutting force and temperature in the machining zone is determined. Experiments are conducted to determine the roughness of the machined surface and the distortion of the samples in various cutting conditions. The results provide the basis for technological recommendations. [ABSTRACT FROM AUTHOR]

Currently the climate computer offers many benefits and solves problems related to the regulation, monitoring and controls. Greenhouse growers remain vigilant and attentive, facing this technological development. They ensure competitiveness and optimize their investments / production cost which continues to grow. The application of artificial intelligence in the industry known for considerable growth, which is not the case in the field of agricultural greenhouses, where enforcement remains timid. It is from this fact, we undertake research work in this area and conduct a simulation based on meteorological data through MATLAB Simulink to finally analyze the thermal behavior greenhouse microclimate energy. In this paper we present comparison of modeling and simulation management of the greenhouse microclimate by fuzzy logic between a wetland (Dar El Beida Algeria) and the other arid (Biskra Algeria).

Improvements in the thermal and energy performance of buildings usually involves techniques with high computational costs, such as multi-objective optimization and parametric simulation. However, sometimes, achieving the optimal case is not desirable, though only the refinement of thermal performance. Hence, methods that enable this analysis are helpful for designers and researchers. Then, this study proposed a framework based on the Heat Exchange Index to assist thermal performance analysis of buildings. The framework consists of two phases and begins by exploring air and surface heat balance derived from the base case building simulation. This analysis is based on the Heat Exchange Index, an index developed in this work, and its result indicates the impact of each heat exchange on the thermal performance. The next phase is the improvement, where strategies are defined and implemented, and the thermal performance of the improved case is evaluated against the base case. A single-family house was modeled using EnergyPlus to demonstrate the framework application. Results showed that the Heat Exchange Index could be used to enhance the thermal performance of buildings since the strategies adopted in the base case increased its thermal autonomy and decreased thermal load. • A framework proposition for early-stage thermal performance analysis of buildings. • The method was based on zone air and surface heat balance. • Development of the Heat Exchange Index to determine the main heat transfer. • The thermal performance of a case study was improved by framework application. [ABSTRACT FROM AUTHOR]

Adequate estimation of water demand in cattle production feed yards is of high importance, especially due to reduced water availability because of changes in rain precipitation patterns and amounts. The pen surface in feed yards receives and reflects solar radiation, affecting along with other factors the microclimate to which cattle are exposed. This study aimed to describe the relationship between the pen surface temperature with the daily water intake and the tympanic temperature of finishing steers. Climate variables, including solar radiation, air temperature, relative humidity, and wind speed plus pen surface temperature and soil temperature at 10.2 cm depth were recorded. Data were collected from a weather station located in the feedlot in Concord NE, whereas daily water intake was estimated from a set of experimental pens sharing a waterer in two adjacent pens. Simple and polynomial linear regressions were assessed from data collected in different experiments conducted from 2003 to 2006. Two models to predict daily water intake were developed for finishing steers using the pen surface temperature as the predictor variable. The first one included data for the period May-October (overall model) and the second one for the summer period (June-August). The best fit for the overall model was a quadratic fit (r2 = 0.86), whereas the best-fit model for the summer model was the cubic (r2 = 0.72). Subsequently, both models were validated with data from an independent experiment conducted in the summer of 2007 in the same facilities. Both models tended to slightly overestimate daily water intake when they were validated (14.6% and 12.6%, respectively). For tympanic temperature, the best-fit model was linear, explaining 76% of the observed variability. When the dataset was split into night-time and daytime the best-fit model for the night period was a quadratic one and a linear one for the daytime, both improving the explanation of the variability observed. In conclusion, pen surface temperature can be used to predict both daily water intake and tympanic temperature in feedlot steers without access to shade.

Due to the large energy consumption as well as poor controllability and other problems, the traditional cooling system has not been able to adapt to the development needs of construction machinery with the continuous upgrading of emission regulations. This paper introduces a hydraulic driven fan cooling system based on pilot operated electro-hydraulic proportional valve. In order to make the whole machine quickly reach the temperature required in the best working condition when the construction machinery starts working, controlling the fan at a lower speed can reduce the heat dissipation and save energy. The electronic control system will adjust the motor speed in time when the temperature of the fluid rises, and control the temperature in the best temperature range required. A one-dimensional simulation model of this stepless speed control system is established to predict the parameter sensitivity of the electro-hydraulic proportional valve and the dynamic performance of the system. The simulation shows that the fan speed of the system can reach the required speed in only 5s at the extreme high temperature of 40 °C; the fan input power of the system accounts for 65% of the system input power at −30 °C and reaches 80% at 40 °C. Three-dimensional simulation shows that the fan-front temperature-controlled cooling system for forklift truck has high heat dissipation efficiency and can be applied to other heavy machinery products. • A hydraulic driven cooling system simulation model is developed. • Parameter sensitivity with pilot relief valve is analyzed. • Dynamic behavior of the system at extreme temperatures is predicted. • Heat transfer efficiency of the system is improved. • Thermal equilibrium temperature is well controlled. [ABSTRACT FROM AUTHOR]

Abstract Background The separate and combined effects of intradialytic exercise training (IET) and cold dialysis (CD) on patient thermoregulation remain unknown. This study assessed the thermoregulatory responses of hemodialysis patients under four different hemodialysis protocols: a) one typical dialysis (TD) protocol (dialysate temperature at 37 °C), b) one cold dialysis (CD) protocol (dialysate temperature at 35 °C), c) one typical dialysis protocol which included a single exercise bout (TD + E), d) one cold dialysis protocol which included a single exercise bout (CD + E). Methods Ten hemodialysis patients (57.2 ± 14.9 years) participated in this randomized, cross-over study. Core and skin temperatures were measured using an ingestible telemetric pill and by four wireless iButtons attached on the skin, respectively. Body heat storage (S) calculated using the thermometric method proposed by Burton. Results The TD and TD + E protocols were associated with increased S leading to moderate effect size increases in core body temperature (as high as 0.4 °C). The low temperature of the dialysate during the CD and the CD + E protocols prevented the rise in S and core temperature (p > 0.05), even during the period that IET took place. Conclusions TD and IET are accompanied by a moderate level of hyperthermia, which can be offset by CD. We recommended that CD or with IET can prevent the excessive rise of S. Trial registration Clinical Trial Registry number: NCT03905551 ( clinicaltrials.gov ), DOR: 05/04/2019,

The article discusses a method for determining the relative eccentricity , used in calculating the thermal balance of an internal combustion engine sliding bearing. When performing this calculation, a number of temperature values are set in the bearing oil layer. For each set temperature, the engine oil viscosity value and the bearing load factor Ф are determined. To determine the relative eccentricity, graphical dependencies of the load factor on the relative eccentricity are used as input data. The thermal calculation of the sliding bearing showed that the accuracy of determining the relative eccentricity is of great importance. Their inaccurate definition leads to a failure of the thermal balance in the bearing. In addition, the method of determining the value of by the accepted value of the ratio of the working length of the bearing to the diameter of the connecting rod neck of the crankshaft (graphically) for this calculation is quite time-consuming. For this reason, the graphical method for determining has been replaced with an analytical one. Relative eccentricities were obtained using the least squares method. An algorithm has been developed for automated construction of transverse and longitudinal profiles of an oil pump with epicycloidal engagement.

Recently, building thermal studies have focused more and more on providing the right living conditions inside buildings, houses, schools, hospitals, etc., especially in hot-dry regions to defeat energy consumption dilemmas generally coming from fossil fuels source by renewable energy. In this paper, a field of experiments in actual conditions is conducted to investigate the influence of external parameters on the occupant's thermal comfort inside a typical dry region house. The obtained results are projected directly on the psychometric chart to position the real thermal comfort current situation. The results confirm the direct influence and indirect influence of external climatic conditions (temperature and humidity, respectively) on internal comfort. Two scenarios with renewable techniques are investigated experimentally based on the obtained results. An earth-to-air heat exchanger (EAHE) and solar chimney (SC) are connected separately to a similar building, and parameters affecting thermal comfort are discussed. The results show that both techniques improve thermal comfort inside the structure with efficiently saving energy. Renewable energy can enhance thermal comfort with significant power- and cost-saving in hot-dry regions.

Copyright of Journal Architecture & Design / Revista de Arquitectura & Diseño is the property of ECORFAN-Mexico S.C. 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.)

The results of experimental and theoretical studies performed to determine the thermal balance and the effective power of air-plasma heating (plasma jet) are presented for a reasonable choice of rational conditions of plasma spraying followed by melting. The theoretical studies take into account the concepts of heat propagation during surfacing processes. The thermal efficiency was experimentally determined by calorimetry using methods for measuring the quantity of heat released or absorbed during various physical or chemical processes. [ABSTRACT FROM AUTHOR]

This paper presents the development and validation of a building integrated photovoltaic (BIPV) simulation platform which can introduce and characterise main faults of BIPV systems. The coupling of the electrical circuit with thermal balance, and the introduction of different faults and their interactions with broken/active protection diodes are among the main contributions of this study. Through comparison with the data measured from a real BIPV installation, it was found that this platform is able to provide an acceptable prediction of the performance of BIPV systems. The design and test of a series of scenarios demonstrated that this platform was capable to simulate and characterise dynamic faulty operations of BIPV systems influenced by various faults. It was found that short-circuit current, gradient information and inflection point in the current-voltage (I–V) curve can be utilised to discriminate the aging and medium partial shading faults with corresponding broken/active bypass diodes. The open-circuit voltage and inflection point in the I–V curve, and the PV cell temperature can be used to distinguish the short-circuit fault in a PV string and inter-string short-circuit fault, with corresponding broken/active blocking diodes. Hotspot phenomenon can also be observed if a minor partial shading fault was introduced in the simulation. • A building integrated PV simulation platform for fault modelling was developed. • Typical PV faults and their interaction with protection diodes were characterised. • Electrical circuit and thermal balance were coupled to simulate PV systems. • Inflection points is the key to discriminating broken/active protection diodes. • Hotspot phenomenon can be simulated by introducing a minor partial shading fault. [ABSTRACT FROM AUTHOR]

Optical cloud radio access network (O-CRAN) is an emerging solution for IIoT, where numerous different devices/nodes are networked together. O-CRAN provides pool of shareable computing facility, equipped with hundreds of general-purpose processor (GPP). The GPPs process massive big data exerted by nodes via remote radio heads (RRHs), regarded as RRH-requests, which are bandwidth-intensive and deadline-constrained digitized base-band signals. Computing resource (CR) optimization has been widely investigated in O-CRAN. However, the existing optimizations may not guarantee workload and thermal balance among the active GPPs while satisfying RRH-request's deadline, which are necessary to efficiently leverage virtualization GPP capacity in a manner that provides the greatest uniform CR utilization (CRU). Due to varying network-load a single optimal solution does not exist. Therefore, in this article, we propose a modified-first-fit decreasing (MFFD) algorithm to obtain a suboptimal solution for each time_stage. The MFFD evenly assigns RRH-requests among GPPs that maximizes individual CRU uniformly contrasting with FFD. [ABSTRACT FROM AUTHOR]

The review focuses on the neuroprotective mechanisms of therapeutic hypothermia from the standpoint of metabolic depression and genomic reprogramming of neurons that develop when brain temperature decreases.The concept of hypothermic pre-conditioning based on the development of typical nonspecific reactions for the formation of the cytoprotective phenotype of neurons due to potentially dangerous stimuli, such as ischemia, reperfusion, and hypothermia, was used to explain the effects of low temperatures. The data confirming the role of therapeutic cerebral hypothermia as a technique of selective brain exposure to mild cold for the neuroprotection and correction of temperature balance disorders are shown.The approach to therapeutic hypothermia as a hypothermic pre-conditioning allows to significantly expand the scope of its use in various procedural variants.

The passive thermal control of a satellite consists of establishing the necessary thermal parameters involved in the process of heat transfer by radiation and conduction in order to delimit the range of temperatures to which the different components will be exposed. If the obtained range implies temperatures that the elements of the satellite are unable to cope with, therefore, an external control is demanded. This work deals with the programming of the equilibrium thermal problem taken into consideration a backward-implicit scheme. The algebraic mathematical approach for steady-state and transient analysis are implemented in Matlab © scripts. In addition, the work analyzes the influence of different coating materials on the passive thermal control of a benchmark spacecraft reported in the literature. The problem under scope considers the characteristics of a low Earth Orbit: the solar, albedo and planetary radiation, the radiation coming from other isotherm surfaces of the same satellite, the heat conduction and, finally, the radiation of these isotherm surfaces to the outer space. The procedure implemented is based on a feasible matrix formulation and results avoid the numerical instabilities prevalent in the forward-explicit approach, moreover, it enables further parametric and sensitivity analysis. Regarding the coating materials influence on the thermal response, the most relevant results evidence that thermal surfaces can guarantee the desirable range of temperature in a spacecraft. We confirm that certain material properties like the absorptance, emittance and its relation (absorption coefficient) are essential in the thermal response of the system. Nevertheless, these thermal properties do not influence in the same way. It is shown that the effect of the emittance is lower than the absorptance. [ABSTRACT FROM AUTHOR]

In the 2019 year, the phenology of the white and black grape varieties for wine was studied, from Medgidia centre and the fertility elements for each variety were determined. Also, the climatic elements specific to 2019 compared to the multiannual average were studied. The year 2019 recorded values close to or higher than the multiannual average for almost all climatic elements, except for the sum of annual rainfall from the vegetation period, where the values are much lower, this year being a deficit in rainfall. According to the value of the Real Heliothermic Index (IHr) of 3.13, the year 2019 registered optimal values for the vine. The study shows that: white varieties for wine, sprouted early, between 15 April ('Chardonnay') and 17April ('Muscat Ottonel'); black varieties, sprouted between 15 April ('Merlot') and 18 April ('Cabernet Sauvignon'); the white varieties bloomed on 5 June ('Merlot') and 7 June ('Cabernet Sauvignon'); the ripe, occurred on different dates for different varieties; full maturity was in 8 September for white varieties and between 17-21 September for the black. For the varieties studied, the largest number of fertile shoots were for 'Muscat Ottonel' (22). [ABSTRACT FROM AUTHOR]

• A correct formulation of average Nusselt number for the case of linearly heated wall is derived. • Thermal balance analysis provides the verification of the correct formulation. • Comparison of the existing and the correct formulation is included. The comment below addresses an inaccurate formulation in the calculation of the Nusselt number for linear heating as presented in the paper titled "Steady natural convection flows in a square cavity with linearly heated side wall(s)" by M. Sathiyamoorthy, T. Basak, S. Roy, and I. Pop, Int. J. Heat Mass Transfer 50 (2007) 766–775. Consequently, this analysis provides a mathematical reformulation for the local and mean Nusselt numbers of a linearly heated side wall. It regenerates a few quantitative results for a specific case solely intended for comparative purposes. [ABSTRACT FROM AUTHOR]

Copyright of Bulletin of the Polytechnic Institute of Iasi - Construction & Architecture Section is the property of Sciendo 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.)

A closed loop adaptive gender-based thermal control system (AG-TCS) is designed, modelled, analysed and tested. The system has the unique feature of adapting to the surrounding environment as a function of the number of humans present and the gender ratio. The operation of the system depends on a unique interface between a radio frequency identification (RFID) device and an imaging device, both of which are correlated and interfaced to a controller. Testing of the system resulted in smooth transition and shape conversion of the response curve, which proved its adaptability. Three mathematical equations describing the internal mechanisms of the AG-TCS are presented and have been proven to optimally reflect the original statistical data covering both genders. [ABSTRACT FROM AUTHOR]

Featured Application: The research results are very valuable for practice because they provide a platform for optimizing of internal conditions in cowsheds by monitoring of internal and external breeding parameters. The results also confirm the positive effect of photovoltaic (PV) modules installation on temperature conditions and Temperature—Humidity—Index (THI) values. This fact is important mainly during the seasonal temperature extremes in summer in the Central European region. This paper is focused on the temperature measurements which can detected the influence of temperature changes on the microclimate in animal production building after the installation of photovoltaic (PV) modules. The first series of experiments were performed on a specially designed model cowshed. For the data comparison and verification, the same measurements were realized in real conditions of the animal production object. The temperature balance was identified by measurements of the temperatures in the different parts of roof, PV modules, and the most important were measurements of the ambient temperature and temperatures in three levels of the cowshed interior. For the confirmation of results, measurements were done in two cowsheds, which had the same azimuth orientation and roof slope. The first cowshed was without installation of the PV modules on the roof and the second building had installed PV modules. By the data analyzed from experimentally obtained time-temperature dependencies, it was found that the installation of PV modules on the cowshed roof had a positive influence on the interior temperature balance. The installation of PV also had a positive effect on the cowshed microclimate, which was declared by calculation of the Temperature—Humidity—Index. [ABSTRACT FROM AUTHOR]

Due to practical limitations in the manufacturing of power semiconductor dies, high power modules are composed of several dies in parallel in order to meet the desired load current requirements. With careful attention to the design, modern insulated gate bipolar transistor (IGBT)-based power modules feature relatively balanced current distribution amongst the parallel dies. However, owing to the increased switching speeds of wide bandgap devices, i.e., silicon carbide (SiC), it is challenging to design the package to achieve both low-loss and balanced operation. In this article, a technique is proposed where the individual dies in a multidie power module can be selectively driven by a closely integrated gate buffer. Amongst the benefits achieved by selectively driving the die gates, a profiling of the power loss within the intelligent power module is enabled. Furthermore, a practical technique to estimate the individual die temperatures is presented, and using the same method, the on-state voltage of the power module during load current conduction can be estimated. Finally, it is experimentally demonstrated that the combination of individual junction temperature estimation and the selective gate driving can be used to increase the power density of the power module by better utilizing the component dies. [ABSTRACT FROM AUTHOR]