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The purpose of this study is to predict the thermal protective performance (TPP) of flame-retardant fabric more economically using machine learning and analyze the factors affecting the TPP using model visualization.

A total of 13 machine learning models were trained by collecting 414 datasets of typical flame-retardant fabric from current literature. The optimal performance model was used for feature importance ranking and correlation variable analysis through model visualization.

Five models with better performance were screened, all of which showed R2 greater than 0.96 and root mean squared error less than 3.0. Heat map results revealed that the TPP of fabrics differed significantly under different types of thermal exposure. The effect of fabric weight was more apparent in the flame or low thermal radiation environment. The increase in fabric weight, fabric thickness, air gap width and relative humidity of the air gap improved the TPP of the fabric.

The findings suggested that the visual analysis method of machine learning can intuitively understand the change trend and range of second-degree burn time under the influence of multiple variables. The established models can be used to predict the TPP of fabrics, providing a reference for researchers to carry out relevant research.

The findings of this study contribute directional insights for optimizing the structure of thermal protective clothing, and introduce innovative perspectives and methodologies for advancing heat transfer modeling in thermal protective clothing.

Selective laser sintering (SLS) is an essential technology in the field of additive manufacturing. However, SLS technology is limited by the traditional point-laser sintering method and has reached the bottleneck of efficiency improvement. This study aims to develop an image-shaped laser sintering (ISLS) system based on a digital micromirror device (DMD) to address this problem. The ISLS system uses an image-shaped laser light source with a size of 16 mm × 25.6 mm instead of the traditional SLS point-laser light source.

The ISLS system achieves large-area image-shaped sintering of polymer powder materials by moving the laser light source continuously in the x-direction and updating the sintering pattern synchronously, as well as by overlapping the splicing of adjacent sintering areas in the y-direction. A low-cost composite powder suitable for the ISLS system was prepared using polyether sulfone (PES), pinewood and carbon black (CB) powders as raw materials. Large-sized samples were fabricated using composite powder, and the microstructure, dimensional accuracy, geometric deviation, density, mechanical properties and feasible feature sizes were evaluated.

The experimental results demonstrate that the ISLS system is feasible and can print large-sized parts with good dimensional accuracy, acceptable geometric deviations, specific small-scale features and certain density and mechanical properties.

This study has achieved the transition from traditional point sintering mode to image-shaped surface sintering mode. It has provided a new approach to enhance the system performance of traditional SLS.

Creativity and productivity are important factors for corporate and government institutions in the COVID-19 era. As a result, there is an urgent need to ensure that construction projects can recover adequately to survive potential surges or even potential epidemics. Therefore, this study aims to explore social capital by examining the effect/impact of knowledge creation on construction performance in the COVID-19 era.

A simple random sampling approach focused on Ghanaian construction firms was used. Completed responses were obtained and analyzed from employees who had tasks on sites. SmartPLS 3.3.3 and Statistical Package for Social Sciences v. 26 was used.

One key finding from this research was that construction firms with solid social capital built by their management staff are more connected and have better adaptive systems than firms with low capital. A company’s development programs must concentrate not only on the development of targeted or selective know-how and professional abilities but also on capacity creating, collaboration and knowledge creation and sharing among its employees.

Using this study’s findings, construction professionals can develop successful solutions to the COVID-19 epidemic and future emergencies. Additionally, the comprehensive exposition of the implications, constraints and preventive methods in this study may enable scholars to discover current gaps in the literature and investigate other elements of the pandemic’s influence on the construction industry.