Semantic Segmentation of Satellite Images for Landslide Detection Using Foreground-Aware and Multi-Scale Convolutional Attention Mechanism.

Advancements in satellite and aerial imagery technology have made it easier to obtain high-resolution remote sensing images, leading to widespread research and applications in various fields. Remote sensing image semantic segmentation is a crucial task that provides semantic and localization information for target objects. In addition to the large-scale variation issues common in most semantic segmentation datasets, aerial images present unique challenges, including high background complexity and imbalanced foreground-background ratios.

Independent Manipulation of Topological Charges and Polarization Patterns of Optical Vortices.

We present a simple and flexible method to generate various vectorial vortex beams (VVBs) with a Pancharatnam phase based on the scheme of double reflections from a single liquid crystal spatial light modulator (SLM). In this configuration, VVBs are constructed by the superposition of two orthogonally polarized orbital angular momentum (OAM) eigenstates. To verify the optical properties of the generated beams, Stokes polarimetry is developed to measure the states of polarization (SOP) over the transverse plane, while a Shack-Hartmann wavefront sensor is used to measure the OAM charge of beams.

Direct optical switching of bistable cholesteric textures in chiral azobenzene-doped liquid crystals.

The direct optical switching of bistable cholesteric textures (i.e., planar and focal conic textures) in chiral azobenzene-doped liquid crystals (LCs) is demonstrated.

All-optically controllable and highly efficient scattering mode light modulator based on azobenzene liquid crystals and poly(N-vinylcarbazole) films.

The present study reports that isothermal phase transition induced by photoisomerization of azobenzene liquid crystals (azo-LCs) from trans- to cis-isomers results in the dissolution of poly(N-vinylcarbazole) (PVK) into azo-LCs. Transparent (scattering) states can be demonstrated using uniform (rough) morphologies of PVK generated by slow (rapid) phase separation of PVK and azo-LCs from cis- to trans-isomers. The PVK films were examined in detail using scanning electron microscopy.

Optically and thermally controllable light scattering based on dye-doped liquid crystals in poly(N-vinylcarbazole) films-coated liquid crystal cell.

This paper presents the optically controllable light scattering based on dye-doped liquid crystals (DDLCs) in a cell, whose substrates are coated with poly(N-vinylcarbazole) (PVK) films. The optical control mechanism is the light-induced dissolution of PVK in DDLCs, which reforms the disordered LC distribution into multiple and micron-sized LC domains. The induced thermal effect on the process is investigated in detail.

Dual liquid crystal alignment configuration based on nanoparticle-doped polymer films.

This paper proposes an approach for producing dual liquid crystal (LC) alignment configuration based on nanoparticle-doped polymer films. Experimental results indicate that illuminating a nanoparticle-doped pre-polymer film, coated onto a substrate with a homogeneous alignment layer, with unpolarized UV light through a photomask causes the polymerization of pre-polymer, ultimately generating homogeneous and vertical alignment layers in unpolymerized and polymerized regions, respectively. The dual LC alignment configuration of the homogeneous (vertical) and hybrid alignments can be achieved by combining the treated substrate with another substrate that has a homogeneous (vertical) alignment layer.

Polarization rotators fabricated by thermally-switched liquid crystal alignments based on rubbed poly(N-vinyl carbazole) films.

This paper demonstrates the thermally-switched liquid crystal (LC) alignments based on a rubbed poly(N-vinyl carbazole) (PVK) film, and their application for polarization rotators. The mechanically rubbed PVK layer can induce a planar alignment of LCs with their director axis perpendicular to the direction of rubbing. This direction can be switched toward the rubbing direction by thermal treatment.