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Durability and multifunctionality are crucial considerations in the realm of electronic textiles. Herein, a hot-pressing process has been developed to enhance the fixation of silver nanowires (AgNWs) on polyethylene terephthalate (PET) fabric. The conductivity, electromagnetic shielding, and electric heating properties of the hot-pressed fabric were measured to demonstrate the effectiveness of the hot-pressing process. The conductivity of the hot-pressed fabric (180 °C for 90 s) was found to be 464.2 S/m, while that of the fabric without hot pressing was 94.9 S/m. The washed hot-pressed fabric was able to provide a maximum electromagnetic shielding of 17 dB, a negative strain sensing performance (the ΔR/R0 of the hot-pressed fabric was maintained at −15%), and an outstanding electric heating property (the temperature reached 110 °C at a current of 0.08 A). This AgNW fabric holds great potential for use in multi-functional wearable devices, and the hot-pressing process improved its stability and durability, making it suitable for industrial production.

Steam curing, a common way of curing precast concrete, can greatly improve its 1-day strength. However, the thermal effect of prolonged high-temperature curing can negatively impact the concrete’s performance, thus compromising production of precast products in cold regions. Fly ash (FA) is used as a supplementary cementitious material to improve part of the properties of concrete. In this paper, we investigated the effect of FA (10~30%) on the compressive strength and microstructure of manufactured sand concrete at the steam curing and later stages. Specifically, we analyzed the behavior of FA in the constant temperature phase under steam curing. Results indicated that the pozzolanic reaction of FA started to occur at 24 h of constant temperature curing. Early hydration under steam curing produces a large amount of Ca(OH)2, causing the pozzolanic reaction of FA to occur significantly earlier, and the high pH value of the solution and the fibrous mesh structure of the FA surface promote the pozzolanic reaction. The addition of 30% FA to manufactured sand concrete causes a significant reduction in early strength under steam curing, which is not beneficial to the formwork removal and tensioning of precast members. Notably, manufactured sand concrete with 20% FA under steam curing had the highest late strength. The filling effect of FA and the additional gel produced by the pozzolanic reaction would result in the reduction in large pore content, refinement of pore size, improvement of microstructural compactness, and increase in gel system strength. Therefore, the addition of 20% FA to the manufactured sand concrete can improve the long-term strength, which is beneficial to the production of precast beams in cold regions.

As a core task of natural language processing and information retrieval, automatic text summarization is widely applied in many fields. There are two existing methods for text summarization task at present: abstractive and extractive. On this basis we propose a novel hybrid model of extractive-abstractive to combine BERT (Bidirectional Encoder Representations from Transformers) word embedding with reinforcement learning. Firstly, we convert the human-written abstractive summaries to the ground truth labels. Secondly, we use BERT word embedding as text representation and pre-train two sub-models respectively. Finally, the extraction network and the abstraction network are bridged by reinforcement learning. To verify the performance of the model, we compare it with the current popular automatic text summary model on the CNN/Daily Mail dataset, and use the ROUGE (Recall-Oriented Understudy for Gisting Evaluation) metrics as the evaluation method. Extensive experimental results show that the accuracy of the model is improved obviously.

To improve the properties of ground granulated blast furnace slag (GGBS) and utilize ground granulated blast furnace slag efficiently, this study investigates the effect of fineness on the hydration activity index (HAI) of ground granulated blast furnace slag. The hydration activity index of GGBS with six specific surface areas (SSAs) was characterized by the ratio of compressive strength of the prismatic mortar test block. The particle size distribution of GGBS with different grinding times was tested by laser particle size analyzer. The paste of different specific surface area GGBSs in different curing ages was investigated at the micro level by X-ray diffraction, scanning electron microscope, energy dispersive spectrometer, thermogravimetric scanning calorimeter, and differential scanning calorimeter. The effect of particle distribution of GGBS on the hydration activity index of different curing ages was studied by gray correlation analysis. The results indicated that the compressive strength and hydration activity index increases with the increase of a specific surface area of GGBS at different curing ages. The hydration activity index at different curing ages is almost a linear role for specific surface areas. With the increase in the specific surface area of GGBS, the content of Ca(OH)2 in paste decreases gradually. When GGBS was added into a mortar test block, the hydrate calcium silicate gel in paste changed from a high Ca/Si ratio to a low Ca/Si ratio. The 0–10 micron particles of GGBS particle distribution were highly correlated with the hydration activity index at different curing ages.

To study different lateral restraints, different constituents of expansion agents, the influence of different steel ratios, and concrete creep properties, we carried out experiments with lateral restraint and without lateral restraint conditions separately on 12 specimens with the expansion agent content accounting for 4%, 8%, and 12% respectively. In addition, the creep tests were performed on specimens with different steel ratios of 0.0%, 3.8%, 6.6%, and 9.2%. The test results show that the lateral restraint improves the strength of the system (concrete-filled steel tubes) which resists further load after the concrete ultimate strength is surpassed and reduces the creep. The creep degree of the concrete-filled steel tube with lateral restraint is about 0.09–0.30 times smaller than that of the tube without lateral restraints. The creep degree of the concrete-filled steel tube increases as the steel ratio decreases. Creep tests with different amounts of expansion agent indicate that the creep degree of the concrete structure increases as expansion agent content decreases. To study the internal mechanism of the creep of concrete-filled steel tubes with different lateral restraints and different expansion agent concentrations, a microscopic pore structure test on the steel core concrete was conducted using the RapidAir457 pore structure instrument. Microscopic studies show that the air content and the length of the bubble chord of the laterally restrained core concrete are lower than those without lateral restraint core concrete. The amount of air content and the length of the bubble chord of core concrete specimens increase as the expansion agent content in the core concrete specimens decreases from 12% to 4%. Under the same external loading conditions, as steel ratio increases, the lateral restraint causes a further reduction of creep. The results of this study suggest that the creep of concrete can be reduced by selecting appropriate lateral restraint conditions and an optimal amount of expansion agent in the mix design of concrete for concrete-filled steel tubes.

To thoroughly explore the relationship between concrete pavement texture characteristics and tire/pavement noise of grooving concrete pavement, the surface texture, i.e., roughness, macrotexture, and microtexture, was investigated in numerous highway pavements. The On-Board Sound Intensity (OBSI) method was used to test the pavement/tire noise. The statistical correlation between concrete pavement texture characteristics and tire/pavement noise was quantitatively described by two correlation analysis methods for highway concrete pavement: origin of linear regression and the Pearson two-sided test method. The results indicate that the effect of pavement roughness on tire/pavement noise is significant, while the noise level is minor for the flat pavement. The macro texture depth also has a marked impact on the tire/pavement noise. In addition, a large grooving depth of concrete pavement could cause a high tire/pavement noise level; however, there is no clear correlation between side-way force coefficient (SFC) and tire/pavement noise.