The aim of this study was to effectively improve the water resistance of a defatted soybean flour (DSF)-based adhesive by subjecting DSF to thermo-chemical treatment in the presence of sodium dodecyl sulfate (SDS), and then the crosslinking with epichlorohydrin-modified polyamide (EMPA). The effect of thermo-chemical treatment on the structures and properties of the DSF and DSF-based adhesive were investigated by plywood evaluation, boiling-water-insoluble content, and acetaldehyde value measurements, as well as FTIR, X-ray photoelectron spectroscopic (XPS), X-ray diffraction spectroscopy (XRD), thermogravimetric analysis (TGA), and rheology analyses. The test results revealed that the water resistance of the DSF-based adhesive was significantly improved, attributed to the formation of a solid three-dimensional crosslinked network structure resulted from the repolymerization of DSF, the Maillard reaction between the protein and carbohydrate, and chemical crosslinking between the crosslinker and DSF. Moreover, SDS destroyed the hydrophobic interactions within protein and inhibited macromolecular aggregations during the thermal treatment. Therefore, more reactive groups buried within the globular structure of the soybean protein component of DSF could be released, which supported the repolymerization, Maillard reaction, and chemical crosslinking of DSF, thereby leading to an improved crosslinking density of the cured DSF-based adhesive. In addition, the adhesive composed of thermo-chemically treated DSF and EMPA exhibited preferable viscosity and viscosity stability suitable for the production of wood composites.

The location information of entities in construction sites, such as workers and construction machines, is valuable in project management and safety. Therefore, as nonintrusive and accurate solutions, various vision-based methods have been proposed to track entities in construction sites and obtain their three-dimensional (3D) coordinates. However, most existing vision-based methods realize 3D localizations by basing entity matching on the epipolar line, which brings instability in entity matching due to the calculation error of the epipolar line or failure to match entities when multiple entities are located on the same epipolar. To solve this problem, a novel framework based on reidentification is proposed to automatically match workers across two camera views, thereby obtaining their 3D coordinates in construction sites. In this framework, deep-learning-based computer vision algorithms are firstly used to detect and track workers in two camera views. Then, the reidentification (ReID) algorithm is applied to utilize tracked workers’ visual features to match the workers across both two camera views and different frames. As a result, for every matched pair, the worker’s pixel locations in two camera views can be obtained to calculate the 3D coordinates through triangulation. The implementation of videos recorded from a real construction project proves the feasibility and accuracy of this framework. Specifically, through utilizing the ReID algorithm to match workers, the framework achieves competitive results on workers matching with precision, recall, and accuracy of more than 99%, 93%, and 93%. Furthermore, it also effectively addresses the practical problems of ID repetition and ID switching. Meanwhile, this paper extends the application scenarios of reidentification algorithms in construction sites, thereby contributing to the future application of multiple-camera vision-based methods in construction sites.

Developing an environmentally friendly soy protein-based film that offers excellent performance has garnered considerable interest while also posing a significant challenge. Herein, we propose the strategy of covalent and noncovalent cross-linking to improve the mechanical properties of the films. First, chemical denaturation was carried out under the combined action of sodium sulfite, sodium dodecyl sulfate, sodium hydroxide, and urea to reshape the structure of the protein to improve the solubility of protein and release active groups. Then, microcrystalline cellulose (MCC) derived from low-cost agro-industrial byproducts (corn husk) was employed to balance the covalent cross-linking reaction between proteins and the noncovalent reaction between MCC and protein. The results indicate that the structure and properties of the soy protein-based films were modified and improved through chemical treatment in conjunction with biomass enhancement. It is concluded that the addition of 1% MCC improves the tensile strength, elastic modulus, water solubility, and water vapor permeability of "MCC-1%" by 64.7, 75.9, 22.7, and 12.9%, respectively. Additionally, the resulting film of "MCC-1%" exhibits better resistance to thermal degradation and improved thermo-stability. However, the elongation at break decreased by increasing the addition of MCC. Thus, this work may provide a simple and affordable approach to preparing a high-performing soy protein-based film.