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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.

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.

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.

This study aims to answer the following questions: How do consumers’ perceptions of brand coolness affect brand relationship outcomes and how do brand coolness effects differ between product brands and service brands?

A quantitative survey was used to collect data from 1,500 consumers assigned to assess one of 20 popular product and service brands in Vietnam. Partial least square structural equation modeling was used to analyze the data.

Data analysis reveals that both dimensions of brand coolness (i.e. self-oriented and other-oriented coolness) exert positive impacts on brand relationship outcomes (i.e. brand satisfaction, brand love and brand advocacy) through brand attitude (i.e. the evaluative mechanism) and self-brand connection (i.e. the identity mechanism). While the identity mechanism of brand coolness effects is more prominent in product brands, the evaluative mechanism is more pronounced for service brands.

This research provides practical guidance for brand managers to build strong customer relationships by leveraging their brand coolness and the mechanisms underlying coolness effects. This study suggests a tailored application of brand coolness dimensions to different branded entities.

This research contributes to the brand coolness literature by validating a two-dimensional brand coolness structure encompassing self-oriented and other-oriented coolness, in accordance with a value-based conceptualization of the concept. For mass brand studies, this study recommends the exclusion of rebellious and subcultural attributes, as well as the utility of pre-determined brands as evaluated objects, in measuring brand coolness. This study also illuminates dual mediation mechanisms and moderation of the branded entity underlying brand coolness effects on consumer–brand relationships.

A combustor design is a particularly important and difficult task in the development of gas turbine engines. During studies for accurate and easy combustor design, reasonable design methodologies have been established and used in engine development. The purpose of this paper is to review the design methodology for combustor in development of advanced gas turbine engines. The advanced combustor development task can be successfully achieved in less time and at lower cost by adopting new and superior design methodologies.

The review considers the main technical problems (combustion, cooling, fuel injection and ignition technology) in the development of modern combustor design and deals with combustor design methods by dividing it into preliminary design, performance evaluation, optimization and experiment. The advanced combustion and cooling technologies mainly used in combustor design are mentioned in detail. In accordance with the modern combustor design method, the design mechanisms are considered and the methods used in every stage of the design are reviewed technically.

The improved performances and strict emission limits of gas turbine engines require the application of advanced technologies when designing combustors. The optimized design mechanism and reasonable performance evaluation methods are very important in reducing experiments and increasing the effectiveness of the design.

This paper provides a comprehensive review of the design methodology for the advanced gas turbine engine combustor.

The final properties of ductile iron are decided by the inoculant processing while pouring the melt. The shape and size of nodules generated during solidification are of paramount importance in solidification of ductile cast iron. The purpose of this study is to examine the effect of different inoculant addition on the solidification of ductile cast iron melt through thermal analysis.

Thermal analysis has recently grown as a tool for modeling the solidification behavior of ductile cast irons. Iron properties will be predicted by analyzing the cooling curve patterns of the melts and predicting the related effectiveness of inoculant processing. In this study, thermal analysis is used to evaluate the need for inoculation.

The amount and type of inoculation will affect the amount of undercooling during the solidification of ductile cast iron. It is found that the addition of 0.1 to 0.4 Wt.% inoculant lowers the austenite dendrite formation starting temperature while increasing the eutectic freezing temperature. Microstructure analysis revealed that the addition of inoculation increases the nodule count from 103 to 242 nodules. The beneficial effects of inoculation are sustained by an improved graphitization factor, which shows the formation of graphite nodules in the second phase of the eutectic reaction.

The inoculation treatment has improved metallurgical occurrences such as carbide to graphite conversion, graphite microstructure control, graphite nodule count at the start of solidification and the last stage of solidification, which determines the soundness of casting. The foundry industry can follow these steps for monitoring the solidification of ductile iron castings.

Electric motor heating during biomass recovery and its handling on conveyor is a serious concern for the motor performance. Thus, the purpose of this paper is to design and develop a hardware prototype of master–slave electric motors based biomass conveyor system to use the motors under normal operating conditions without overheating.

The hardware prototype of the system used master–slave electric motors for embedded controller operated robotic arm to automatically replace conveyor motors by one another. A mixed signal based embedded controller (C8051F226DK), fully compliant with IEEE 1149.1 specifications, was used to operate the entire system. A precise temperature measurement of motor with the help of negative temperature coefficient sensor was possible due to the utilization of industry standard temperature controller (N76E003AT20). Also, a pulse width modulation based speed control was achieved for master–slave motors of biomass conveyor.

As compared to conventional energy based mains supply, the system is self-sufficient to extract more energy from solar supply with an energy increase of 11.38%. With respect to conventional energy based \ of 47.31%, solar energy based higher energy saving of 52.69% was reported. Also, the work achieved higher temperature reduction of 34.26% of the motor as compared to previous cooling options.

The proposed technique is free from air, liquid and phase-changing material based cooling materials. As a consequence, the work prevents the wastage of these materials and does not cause the risk of health hazards. Also, the motors are used with their original dimensions without facing any leakage problems.

This study aims to demonstrate a modified wire arc additive manufacturing (AM) named non-transferring arc and wire AM (NTA-WAM). Here, the build plate has no electrical arc attachment, and the system’s arc is ignited between tungsten electrode and filler wire.

The effect of various deposition conditions (welding voltage, travel speed and wire feed speed [WFS]) on bead characteristics is studied through response surface methodology (RSM). Under optimum deposition condition, a single-bead and thin-layered part is fabricated and subjected to microstructural, tensile testing and X-ray diffraction study. Moreover, bulk texture analysis has been carried out to illustrate the effect of thermal cycles and tensile-induced deformations on fibre texture evolutions.

RSM illustrates WFS as a crucial deposition parameter that suitably monitors bead width, height, penetration depth, dilution, contact angle and microhardness. The ferritic (acicular and polygonal) and lath bainitic microstructure is transformed into ferrite and pearlitic micrographs with increasing deposition layers. It is attributed to a reduced cooling rate with increased depositions. Mechanical testing exhibits high tensile strength and ductility, which is primarily due to compressive residual stress and lattice strain development. In deposits, ϒ-fibre evolution is more resilient due to the continuous recrystallisation process after each successive deposition. Tensile-induced deformation mostly favours ζ and ε-fibre development due to high strain accumulations.

This modified electrode arrangement in NTA-WAM suitably reduces spatter and bead height deviation. Low penetration depth and dilution denote a reduction in heat input that enhances the cooling rate.