Search Results - Liu liu

To address the issue of declined cooling performance caused by the recirculation of hot jet flow into the cavity of conventional synthetic jet actuators, a loudspeaker-driven thermoacoustic-cooling synthetic jet actuator was developed by integrating a thermoacoustic cooler with a synthetic jet actua...

Full description

In view of the problem of the plastic state of the surrounding rock of loess high-speed railway tunnels changing from hard plastic to soft-plastic, even in a flow-plastic state with increasing moisture content, and appearing collapse and large deformation of support structure, it is put forward to u...

Full description

The study optimizes the flight trajectory and power of multiple unmanned aerial vehicles with the deep deterministic policy gradient algorithm and constructs a multi-unmanned aerial vehicle semantic communication optimization model based on singular value decomposition and multi-agent deep reinforce...

Full description

A multimode bus structure consisting of densely packed uniform waveguide array (DPUWA) with a narrow gap of 150 nm is proposed. A compact and robust mode converter between DPUWA and a conventional wide multimode waveguide is designed with an insertion loss of <0.05 dB and crosstalk of &lt...

Full description

Thin film lithium niobate (LN) shows great potentials for highly compact passive and active devices. As LN is an anisotropic material, waveguides made on it exhibit different mode properties from those on conventional isotropic materials. We study the effective refractive indices of fundamental mode...

Full description

Although there is an increasing interest in forecasting global and regional vegetation productivity trends under climate change, it remains unclear whether the effects of water availability on vegetation growth are changing. This study evaluates the long-term trends and time thresholds (the time req...

Full description

A free space vortex light generator is designed based on the diffraction of an optical Bessel beam. The Bessel beam propagating in a single mode fiber is modulated by a helical phase disk designed at the fiber end and gradually evolves to vortex light in free space. The properties of the generator s...

Full description

We design a 121-channel on-chip spectrometer based on an echelle grating with densely packed waveguide array on 220-nm silicon-on-insulator platform. It offers a high spectral resolution of 0.5 nm in a 3 ^* 3 mm² footprint, covering a spectral...

Full description

As an important supplement to the ground network, the low earth orbit (LEO) satellite network is an important component of the integrated network of space and earth. Due to the high moving speed of LEO satellites, a large Doppler frequency offset and its rate of change are caused, so a new frequency...

Full description

IntroductionConstruction of an animal model of rabbit anterior cruciate ligament (ACL) near isometric reconstruction is a basic condition to study the patterns of graft stress and tendon to bone healing. The impact of alterations in the bone tunnel entrance within the femoral footprint region on gra...

Full description

This review explores polarization mode hybridization in x‐cut thin‐film lithium niobate (TFLN) waveguides and its implications for the design of photonic integrated device. It addresses strategies to mitigate anisotropy and mode hybridization as well as approaches to exploit these effects for advanc...

Full description

A six-channel wavelength-division-multiplexed optical transceiver with a compact footprint of 1.5 <inline-formula> <tex-math notation="LaTeX">$\times$</tex-math></inline-formula> 0.65 mm² for off-chip and on-chip interconnects is demonstrated...

Full description

Abstract Photonic manipulation of large‐capacity data with the advantages of high speed and low power consumption is a promising solution for explosive growth demands in the era of post‐Moore. A well‐developed lithium‐niobate‐on‐insulator (LNOI) platform has been widely explored for high‐performance...

Full description