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Wireless sensor network (WSN) location is a significant research area. In complex environments like forests, inaccurate signal intensity ranging is a major challenge. To address this issue, this paper presents a reliable WSN distance measurement-positioning algorithm for forest environments. The algorithm divides the positioning area into several sub-regions based on the discrete coefficient of the collected signal strength. Then, using the fitting method based on the signal intensity value of each sub-region, the algorithm derives the reference points of the logarithmic distance path loss model and path loss index. Finally, the algorithm locates target nodes using anchor nodes in different regions. Additionally, to enhance the positioning accuracy, weight values are assigned to the positioning result based on the discrete coefficient of the signal intensity in each sub-region. Experimental results demonstrate that the proposed WSN algorithm has high precision in forest environments. [ABSTRACT FROM AUTHOR]

Birds play a vital role in maintaining biodiversity. Accurate identification of bird species is essential for conducting biodiversity surveys. However, fine-grained image recognition of birds encounters challenges due to large within-class differences and small inter-class differences. To solve this problem, our study took a part-based approach, dividing the identification task into two parts: part detection and identification classification. We proposed an improved bird part detection algorithm based on YOLOv5, which can handle partial overlap and complex environmental conditions between part objects. The backbone network incorporates the Res2Net-CBAM module to enhance the receptive fields of each network layer, strengthen the channel characteristics, and improve the sensitivity of the model to important information. Additionally, in order to boost data on features extraction and channel self-regulation, we have integrated CBAM attention mechanisms into the neck. The success rate of our suggested model, according to experimental findings, is 86.6%, 1.2% greater than the accuracy of the original model. Furthermore, when compared with other algorithms, our model's accuracy shows noticeable improvement. These results show how useful the method we suggested is for quickly and precisely recognizing different bird species. [ABSTRACT FROM AUTHOR]

Due to their high surface energy, naked gold nanoparticles (AuNPs) tend to form agglomerates, which could lead to the decrease of active sites and catalytic activity of AuNPs. Herein, the gold nanoparticles/polyacrylonitrile (AuNPs/PAN) nanofibrous membranes have been prepared via an environmentally friendly and efficient route combining electrospinning, amination, and electroless plating technique. The abundant amine and imine groups can be introduced onto the surface of PAN nanofibrous membranes via amination treatment which could be used as 'anchoring sites' to immobilize AuNPs. The resultant composite membranes were applied as the new catalytic materials for reduction of 4-nitrophenol to 4-aminophenol under room temperature. The new catalytic membranes exhibited the significant advantages, such as low dosage, high catalytic activity, easy recycling, and excellent stability. [ABSTRACT FROM AUTHOR]

Freestanding paper-like materials prepared from chemically derived graphene have considerable potential as a carbon-based catalyst in high-performance flexible catalytic reaction. Herein, a highly flexible graphene paper (GP) assembled from graphene oxides (GOs) with the aid of polyacrylamide (PAA) and electroless deposition of gold nanoparticles (AuNPs) was prepared. In contrast to previous reports on GOs based on a flow-directed assembly of graphene sheets, this GOs/PAA/Au composite paper exhibited a highly wrinkled and disordered morphology. The resultant GOs/PAA/Au composite paper was applied as a catalytic material for the reduction of 4-nitrophenol and showed the favour separation, recovery and cyclic utilization properties. [ABSTRACT FROM AUTHOR]

The multi-sensitive micelles were prepared through a photoinitiated polymerization and self-assembly route using 2-ketobutyric acid (2-KBA) as effective water-soluble photoinitiator and emulsifier. The drug release behaviors were investigated under different glucose concentration, pH and temperature conditions. This work provides a new platform for development drug delivery vehicles with reducing possible utilization of organic solvents and initiators and surfactants. [ABSTRACT FROM AUTHOR]