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This study investigates the impact of the fire decay phase on structural damage using the sectional analysis method. The primary objective of this work is to forecast the non-dimensional capacity parameters for the axial and flexural load-carrying capacity of reinforced concrete (RC) sections for heating and the subsequent post-heating phase (decay phase) of the fire.

The sectional analysis method is used to determine the moment and axial capacities. The findings of sectional analysis and heat transfer for the heating stage are initially validated, and the analysis subsequently proceeds to determine the load capacity during the fire’s heating and decay phases by appropriately incorporating non-dimensional sectional and material parameters. The numerical analysis includes four fire curves with different cooling rates and steel percentages.

The study’s findings indicate that the rate at which the cooling process occurs after undergoing heating substantially impacts the axial and flexural capacity. The maximum degradation in axial and flexural capacity occurred in the range of 15–20% for cooling rates of 3 °C/min and 5 °C/min as compared to the capacity obtained at 120 min of heating for all steel percentages. As the fire cooling rate reduced to 1 °C/min, the highest deterioration in axial and flexural capacity reached 48–50% and 42–46%, respectively, in the post-heating stage.

The established non-dimensional parameters for axial and flexural capacity are limited to the analysed section in the study owing to the thermal profile, however, this can be modified depending on the section geometry and fire scenario.

The study primarily focusses on the degradation of axial and flexural capacity at various time intervals during the entire fire exposure, including heating and cooling. The findings obtained showed that following the completion of the fire’s heating phase, the structural capacity continued to decrease over the subsequent post-heating period. It is recommended that structural members' fire resistance designs encompass both the heating and cooling phases of a fire. Since the capacity degradation varies with fire duration, the conventional method is inadequate to design the load capacity for appropriate fire safety. Therefore, it is essential to adopt a performance-based approach while designing structural elements' capacity for the desired fire resistance rating. The proposed technique of using non-dimensional parameters will effectively support predicting the load capacity for required fire resistance.

The fire-resistant requirements for reinforced concrete structures are generally established based on standard fire exposure conditions, which account for the fire growth phase. However, it is important to note that concrete structures can experience internal damage over time during the decay phase of fires, which can be quantitatively determined using the proposed non-dimensional parameter approach.

This study aims to analyze the relationship of mass versus niche brand coolness on consumers’ brand loyalty, mediated by attitude toward the brand and moderated by conspicuous consumption; test the moderating role of conspicuous consumption and the mediating role of attitude between mass versus niche cool brand and brand love; and analyze whether results are stable when categorizing the luxury brands as niche versus mass cool brand.

Study 1 uses a panel sample to establish the mediating role of attitude toward the brand between perceptions of brand coolness and brand loyalty. Study 2 is an experimental survey study to describe the moderating role of conspicuous consumption on the relationship between mass/niche brand coolness and brand love and between mass/niche coolness and attitude toward the brand. Study 3 is a conjoint analysis that delineates the distinct factors that consumers attribute to mass versus niche cool brands in the luxury fashion arena.

This study demonstrates that attitudes mediate the relationship between brand coolness and brand loyalty. Conspicuous consumption only moderates the relationship between brand coolness and attitudes in the case of niche cool brands. In a realistic field experiment, the authors confirm the mediating impact of attitude and the moderating influence of conspicuous consumption. The authors also attempt to provide coolness dimensions that tend to be more associated with mass luxury brands and those more related to niche luxury brands.

These studies provide a fresh look at the concept of brand coolness, mass and niche cool brands in the context of luxury fashion brands.

Esta investigación pretende (1) analizar la relación entre el atractivo de las marcas de nicho y de masas y la lealtad a la marca de los consumidores, mediada por la actitud hacia la marca y moderada por el consumo conspicuo, (2) comprobar el papel moderador del consumo conspicuo y el papel mediador de la actitud entre el atractivo de las marcas de nicho y de masas y el amor por la marca y (3) analizar si los resultados son estables al categorizar las marcas de lujo como de nicho o de masas.

Demostramos que las actitudes median en la relación entre el “coolness” y la fidelidad a una marca. El consumo ostentoso sólo modera la relación entre el “coolness” de la marca y las actitudes en el caso de las marcas “cool” de nicho. En un experimento de campo realista, confirmamos el efecto mediador de la actitud y la influencia moderadora del consumo ostentoso. También intentamos proporcionar las dimensiones del coolness que tienden a asociarse más con las marcas de lujo de masas y las que están más relacionadas con las marcas de lujo de nicho.

El primer estudio utiliza una muestra de panel para establecer el papel mediador de la actitud hacia la marca entre las percepciones del atractivo de la marca y la fidelidad a la misma. El segundo es un estudio experimental que describe el papel moderador del consumo ostentoso en la relación entre el atractivo de las marcas de masas/nicho y el amor por la marca, y entre el atractivo de las marcas de masas/nicho y la actitud hacia la marca. El último estudio es un análisis conjunto que delinea los distintos factores que los consumidores atribuyen a las marcas de moda de masas frente a las de nicho en el ámbito de la moda de lujo.

Estos estudios aportan una nueva mirada al concepto de “coolness” de marca, marcas “cool” de masas y marcas “cool” de nicho en el contexto de las marcas de moda de lujo.

本研究旨在：（1）分析大众品牌酷与小众品牌酷对消费者品牌忠诚度的关系, 以对品牌的态度为中介, 以显性消费为调节; （2）检验显性消费的调节作用以及态度在大众品牌酷与小众品牌酷与品牌喜爱之间的中介作用; （3）分析将奢侈品牌分为小众品牌酷与大众品牌酷时, 结果是否稳定。

第一项研究使用小组样本, 以确定对品牌的态度在品牌酷感和品牌忠诚度之间的中介作用。第二项研究是一项实验性调查研究, 目的是描述显性消费对大众/小众品牌酷感与品牌喜爱之间以及大众/小众品牌酷感与品牌态度之间关系的调节作用。最后一项研究是一项联合分析, 旨在界定消费者对奢侈时尚领域中大众与小众酷品牌的不同评价因素。

研究结果 我们证明, 态度是品牌酷感与品牌忠诚度之间关系的中介。只有在小众酷品牌的情况下, 显性消费才会调节品牌酷度与态度之间的关系。在一个真实的现场实验中, 我们证实了态度的中介作用和显性消费的调节作用。我们还试图提供与大众奢侈品牌更相关的酷感维度, 以及与小众奢侈品牌更相关的酷感维度。

这些研究以奢侈时尚品牌为背景, 重新审视了品牌酷度、大众和小众酷度品牌的概念。

This study aims to examine the effects of cross-flow and multiple jet impingement on conductive panel cooling performance when subjected to uniform magnetic field effects. The cooling system has double rotating cylinders.

Cross-flow ratios (CFR) ranging from 0.1 to 1, magnetic field strength (Ha) ranging from 0 to 50 and cylinder rotation speed (Rew) ranging from −5,000 to 5,000 are the relevant parameters that are included in the numerical analysis. Finite element method is used as solution technique. Radial basis networks are used for the prediction of average Nusselt number (Nu), average surface temperature of the panel and temperature uniformity effects when varying the impacts of cross-flow, magnetic field and rotations of the double cylinder in the cooling channel.

The effect of CFR on cooling efficiency and temperature uniformity is favorable. By raising the CFR to the highest value under the magnetic field, the average Nu can rise by up to 18.6%, while the temperature drop and temperature difference are obtained as 1.87°C and 3.72°C. Without cylinders, magnetic field improves the cooling performance, while average Nu increases to 4.5% and 8.8% at CR = 0.1 and CR = 1, respectively. When the magnetic field is the strongest with cylinders in channel at CFR = 1, temperature difference (ΔT) is obtained as 2.5 °C. The rotational impacts on thermal performance are more significant when the cross-flow effects are weak (CFR = 0.1) compared to when they are substantial (CFR = 1). Cases without a cylinder have the worst performance for both weak and severe cross-flow effects, whereas using two rotating cylinders increases cooling performance and temperature uniformity for the conductive panel. The average surface temperature lowers by 1.2°C at CFR = 0.1 and 0.5°C at CFR = 1 when the worst and best situations are compared.

The outcomes are relevant in the design and optimization-based studies for electric cooling, photo-voltaic cooling and battery thermal management.

Maintaining the turbine blade’s temperature within the safety limit is challenging in high-pressure turbines. This paper aims to numerically present the conjugate heat transfer analysis of a novel approach to mini-channel embedded film-cooled flat plate.

Numerical simulations were performed at a steady state using SST k – ω turbulence model. Impingement and film cooling are classical approaches generally adopted for turbine blade analysis. The existing film cooling techniques were compared with the proposed design, where a mini-channel was constructed inside the solid plate. The impact of the blowing ratio (M), Biot number (Bi) and temperature ratio (TR) on overall cooling performance was also studied.

Overall cooling effectiveness was always shown to be higher for mini-channel embedded film-cooled plates. The effectiveness increases with increasing the blowing ratio from M = 0.3 to 0.7, then decreases with increasing blowing ratio (M = 1 and 1.4) due to lift-off conditions. The mini-channel embedded plate resulted in an approximately 21% increase in area-weighted average overall effectiveness at a blowing ratio of 0.7 and Bi = 1.605. The lower uniform temperature was also found for all blowing ratios at a low Biot number, where conduction heat transfer significantly impacts total cooling effectiveness.

To the best of the authors’ knowledge, this study presents a novel approach to improve the cooling performances of a film-cooled flat plate with better cooling uniformity by using embedded mini-channels. Despite the widespread application of microchannels and mini-channels in thermal and fluid flow analysis, the application of mini-channels for blade cooling is not explored in detail.

As data centres grow in size and complexity, traditional air-cooling methods are becoming less effective and more expensive. Immersion cooling, where servers are submerged in a dielectric fluid, has emerged as a promising alternative. Ensuring reliable operations in data centre applications requires the development of an effective control framework for immersion cooling systems, which necessitates the prediction of server temperature. While deep learning-based temperature prediction models have shown effectiveness, further enhancement is needed to improve their prediction accuracy. This study aims to develop a temperature prediction model using Long Short-Term Memory (LSTM) Networks based on recursive encoder-decoder architecture.

This paper explores the use of deep learning algorithms to predict the temperature of a heater in a two-phase immersion-cooled system using NOVEC 7100. The performance of recursive-long short-term memory-encoder-decoder (R-LSTM-ED), recursive-convolutional neural network-LSTM (R-CNN-LSTM) and R-LSTM approaches are compared using mean absolute error, root mean square error, mean absolute percentage error and coefficient of determination (R²) as performance metrics. The impact of window size, sampling period and noise within training data on the performance of the model is investigated.

The R-LSTM-ED consistently outperforms the R-LSTM model by 6%, 15.8% and 12.5%, and R-CNN-LSTM model by 4%, 11% and 12.3% in all forecast ranges of 10, 30 and 60 s, respectively, averaged across all the workloads considered in the study. The optimum sampling period based on the study is found to be 2 s and the window size to be 60 s. The performance of the model deteriorates significantly as the noise level reaches 10%.

The proposed models are currently trained on data collected from an experimental setup simulating data centre loads. Future research should seek to extend the applicability of the models by incorporating time series data from immersion-cooled servers.

The proposed multivariate-recursive-prediction models are trained and tested by using real Data Centre workload traces applied to the immersion-cooled system developed in the laboratory.

This study aims to evaluate the thermal performance of sodium alginate (SA) aerogel attached to nano SiO₂ and its radiative cooling effect on firefighting clothing without environmental pollution.

SA/SiO₂ aerogel with refractory heat insulation and enhanced radiative cooling performance was fabricated by freeze-drying method, which can be used in firefighting clothing. The microstructure, chemical composition, thermal stability, and thermal emissivity were analyzed using Fourier transform infrared spectroscopy, scanning electron microscopy, thermogravimetric analyzer and infrared emissivity measurement instrument. The radiative cooling effect of aerogel was studied using thermal infrared imager and thermocouple.

When the addition of SiO₂ is 25% of SA, the prepared aerogel has excellent heat insulation and a high radiative cooling effect. Under a clear sky, the temperature of SA/SiO₂ aerogel is 9.4°C lower than that of pure SA aerogel and 22.1°C lower than that of the simulated environment. In addition, aerogel has more exceptional heat insulation effect than other common fabrics in the heat insulation performance test.

SA/SiO₂ aerogel has passive radiative cooling function, which can efficaciously economize global energy, and it is paramount to environment-friendly cooling.

This method could pave the way for high-performance cooling materials designed for firefighting clothing to keep maintain the wearing comfort of firefighters.

SA/SiO₂ aerogel used in firefighting clothing can release heat to the low-temperature outer space in the form of thermal radiation to achieve its own cooling purpose, without additional energy supply.

This study aims to explore and extend the consumer–brand relationship literature by integrating the relatively new construct of brand coolness with a growing body of work on gratitude. Specifically, gratitude is explored alongside emotional brand attachment as an additional mechanism affecting the relationship between cool brands and the loyalty outcome of repurchase intention. Consumption context is examined as a boundary condition to the effect of gratitude.

Data was collected from an online survey of a Qualtrics panel of 356 US consumers. A moderated mediation model is used to explain the effects of brand coolness on repurchase intention via emotional brand attachment and brand gratitude in the moderating presence of consumption context.

Brand coolness significantly increases repurchase intention. Furthermore, emotional brand attachment and brand gratitude are established as parallel mediators of the relationship between brand coolness and repurchase intention, with brand gratitude exhibiting a significantly stronger mediated effect. The impact of brand coolness on brand gratitude is moderated by social visibility, with publicly consumed cool brands stimulating greater brand gratitude than their privately consumed counterparts.

Brand gratitude is shown to influence repurchase intention independent of the impact exerted by consumers’ emotional brand attachment. Cognitive appraisal theory is used to distinguish brand gratitude from other mediators studied in consumer–brand relationships. Findings establish the moderating influence of the social visibility of the brand on the relationship between brand coolness and gratitude.

This paper investigates the optimization of window design factors (WDFs) in hospital buildings, particularly in government hospitals within the arid climate of the Qassim region, with the aim of achieving a better cooling load reduction. Continuous monitoring of the hospital ward section is crucial due to patients' needs, requiring optimal indoor air quality and cooling load.

The study identifies the optimal conditions for WDF design to mitigate cooling load, including window-to-wall ratio (WWR), window orientation (WO), room size and U-value (thermal properties), effectively reduce energy consumption in terms of sensible cooling load (MWh/m2) and comply with local codes. Data collection involved a smart weather station, while the Integrated Environmental Solution Virtual Environment (IESVE) software facilitated the simulation process.

Key findings reveal that larger patient rooms were about 40% more energy-efficient than smaller rooms. The northern orientation showed lower energy consumption, and specific WWRs and glazing U-values significantly affected energy loads. In an analysis of U-value changes in energy performance based on the Saudi Building Code (SBC), the presented values did not meet the minimum energy consumption standards. For a valid 40% WWR with a thermal permeability of 2.89, 0.181 MWh/m2 was consumed, while for an invalid 100% WWR with the same permeability but facing the north, 0.156 MWh/m2 was consumed, which is considered an invalid practice. It is vital to follow prescribed standards to ensure energy efficiency and avoid unnecessary costs.

Focus lies in emphasizing the significance of adhering to prescribed standards, such as SBC, to guarantee energy efficiency and prevent unwarranted expenses. Additionally, the authors highlight the crucial role of optimizing glazing properties and allocating the WWR appropriately to achieve energy-efficient building design, accounting for diverse orientations and climatic conditions.

The purpose of this study is to improve the thermal management of lithium-ion batteries. The phase change material (PCM) cooling does not require additional equipment to consume energy. To improve the heat dissipation capacity of batteries, fins are added in the PCM to enhance the heat transfer process.

Computational fluid dynamics method is used to study the influence of number of vertical fins and ring fins (i.e. 2, 4, 6 and 8 vertical fins, and 2, 3, 4 and 5 ring fins) and the combination of them on the cooling performance.

The battery maximum temperature can be decreased by the PCM with vertical or ring fins, and it can be further decreased by the combination of them. The PCM with eight vertical fins and five ring fins reduces the battery maximum temperature by 5.21 K. In addition, the temperature and liquid-phase distributions of the battery and PCM are affected by the design of the cooling system.

This work can provide guidelines for the development of new and efficient PCM cooling systems for lithium-ion batteries.

The combination of PCM and fins can be used to reduce the battery maximum temperature and temperature difference.

The capability of steel columns to support their design loads is highly affected by the time of exposure and temperature magnitude, which causes deterioration of mechanical properties of steel under fire conditions. It is known that structural steel loses strength and stiffness as temperature increases, particularly above 400 °C. The duration of time in which steel is exposed to high temperatures also has an impact on how much strength it loses. The time-dependent response of steel is critical when estimating load carrying capacity of steel columns exposed to fire. Thus, investigating the structural response of cold-formed steel (CFS) columns is gaining more interest due to the nature of such structural elements.

In this study, experiments were conducted on two CFS configurations: back-to-back (B-B) channel and toe-to-toe (T-T) channel sections. All CFS column specimens were exposed to different temperatures following the standard fire curve and cooled by air or water. A total of 14 tests were conducted to evaluate the capacity of the CFS sections. The axial resistance and yield deformation were noted for both section types at elevated temperatures. The CFS column sections were modelled to simulate the section's behaviour under various temperature exposures using the general-purpose finite element (FE) program ABAQUS. The results from FE modelling agreed well with the experimental results. Ultimate load of experiment and finite element model (FEM) are compared with each other. The difference in percentage and ratio between both are presented.

The results showed that B-B configuration showed better performance for all the investigated parameters than T-T sections. A noticeable loss in the ultimate strength of 34.5 and 65.6% was observed at 90 min (986℃) for B-B specimens cooled using air and water, respectively. However, the reduction was 29.9 and 46% in the T-T configuration, respectively.

This research paper focusses on assessing the buckling strength of heated CFS sections to analyse the mode of failure of CFS sections with B-B and T-T design configurations under the effect of elevated temperature.