3D-printed mm-wave dielectric spherical conformal transmitarray for multi-order and multi-beam OAM generation.

In this paper, what we believe to be a novel 3D-printed mm-wave dielectric spherical conformal transmitarray with octagonal cylindrical dielectric elements is proposed for generating multi-order OAM beams. By adjusting the wall thickness of the cylindrical dielectric unit, a full 360° transmission phase shift with high transmission efficiency is achieved in the millimeter-wave band of 25-27 GHz. According to the design principles of spherical structures, the elements are arranged to form an OAM-generating spherical conformal transmitarray.

Subregional parabolic conformal multi-order OAM-generating transmitarray with a novel C-I-shaped grating cell.

A parabolic conformal multi-order OAM-generating transmitarray with novel C-I-shaped grating cell is presented in this paper. The novel cell is composed of three layers of the upper and lower grating structures, and the C-I-shaped metal in the middle layer. Compared with the traditional C-shaped structure, the novel cell can be adjusted to cover 360° transmission phase change with high transmission coefficient at the frequency band of 10-20 GHz.

Blockchain-Based Neural Network Model for Agricultural Product Cold Chain Coordination.

This paper adopts a blockchain fusion neural network algorithm to conduct an in-depth study on the model of agricultural cold chain coordination. We aim to enable HDFS to meet the demand of storing many small files of various types generated by various stages of agricultural cold chain coordination and then propose an improved balanced merging and index caching strategy based on file types and size grouping. The main three modules are the file preprocessing module, file balanced merging module, and index caching module.