Amorphous SiO₂(a-SiO₂) thin films are widely used in integrated circuits (ICs) due to their excellent thermal stability and insulation properties. In this paper, the thermal conductivity of a-SiO₂thin film was systematically investigated using non-equilibrium molecular dynamics (NEMD) simulations. In addition to the size effect and the temperature effect for thermal conductivity of a-SiO₂thin films, the effect of defects induced thermal conductivity tuning was also examined. It was found that the thermal conductivity of a-SiO₂thin films is insensitive to the temperature from −55 °C to 150 °C. Nevertheless, in the range of the thickness in this work, the thermal conductivity of the crystalline SiO₂(c-SiO₂) thin films conforms to the T^−αwith the exponent range from −0.12 to −0.37, and the thinner films are less sensitive to temperature. Meanwhile, the thermal conductivity of a-SiO₂with thickness beyond 4.26 nm has no significant size effect, which is consistent with the experimental results. Compared with c-SiO₂thin film, the thermal conductivity of a-SiO₂is less sensitive to defects. Particularly, the effect of spherical void defects on the thermal conductivity of a-SiO₂is followed by Coherent Potential model, which is helpful for the design of low-K material based porous a-SiO₂thin film in microelectronics.

Coral reef habitat structural complexity influences key ecological processes, ecosystem biodiversity, and resilience. Measuring structural complexity underwater is not trivial and researchers have been searching for accurate and cost-effective methods that can be applied across spatial extents for over 50 years. This study integrated a set of existing multi-view, image-processing algorithms, to accurately compute metrics of structural complexity (e.g., ratio of surface to planar area) underwater solely from images. This framework resulted in accurate, high-speed 3D habitat reconstructions at scales ranging from small corals to reef-scapes (10s km²). Structural complexity was accurately quantified from both contemporary and historical image datasets across three spatial scales: (i) branching coral colony (Acropora spp.); (ii) reef area (400 m²); and (iii) reef transect (2 km). At small scales, our method delivered models with <1 mm error over 90% of the surface area, while the accuracy at transect scale was 85.3% ± 6% (CI). Advantages are: no need for an a priori requirement for image size or resolution, no invasive techniques, cost-effectiveness, and utilization of existing imagery taken from off-the-shelf cameras (both monocular or stereo). This remote sensing method can be integrated to reef monitoring and improve our knowledge of key aspects of coral reef dynamics, from reef accretion to habitat provisioning and productivity, by measuring and up-scaling estimates of structural complexity.

The mosaicking of Unmanned Aerial Vehicle (UAV) imagery usually requires information from additional sensors, such as Global Position System (GPS) and Inertial Measurement Unit (IMU), to facilitate direct orientation, or 3D reconstruction approaches (e.g., structure-from-motion) to recover the camera poses. In this paper, we propose a novel mosaicking method for UAV imagery in which neither direct nor indirect orientation procedures are required. Inspired by the embedded deformation model, a widely used non-rigid mesh deformation model, we present a novel objective function for image mosaicking. Firstly, we construct a feature correspondence energy term that minimizes the sum of the squared distances between matched feature pairs to align the images geometrically. Secondly, we model a regularization term that constrains the image transformation parameters directly by keeping all transformations as rigid as possible to avoid global distortion in the final mosaic. Experimental results presented herein demonstrate that the accuracy of our method is twice as high as an existing (purely image-based) approach, with the associated benefits of significantly faster processing times and improved robustness with respect to reference image selection.

Silicon Carbide (SiC) is a typical material for third-generation semiconductors. The thermal boundary resistance (TBR) of the 4H-SiC/SiO₂ interface was investigated by both experimental measurements and theoretical calculations. The structure of 4H-SiC/SiO₂ was characterized by using transmission electron microscopy and X-ray diffraction. The TBR was found to be 8.11 × 10⁻⁸ m²K/W at 298 K by the 3ω method. Furthermore, the diffuse mismatch model was employed to predict the TBR of different interfaces, which is in good agreement with measurements. Heat transport behavior based on the phonon scattering perspective was also discussed to understand the variations of TBR across different interfaces. Besides, the intrinsic thermal conductivity of SiO₂ thin films (200–1500 nm in thickness) on 4H-SiC substrates was measured by the 3ω procedure, to be 1.42 W/m K at 298 K. It is believed the presented results could provide useful insights into the thermal management and heat dissipation for SiC devices.

To achieve less than 50 N soft-landing using magneto-rheological fluid (MRF) damper, a novel small-MRF damper has been developed. First, we design a new outer electromagnetic coil comparing with traditional inner coil structure, which can obtain miniature damper easily and control the magnetic field conveniently. Second, we apply silicon steel rather than carbon steel for MRF damper, which can improve the performance of response and demagnetization of the damper. The effectiveness of the innovative design is confirmed by experiments in this paper. The range of soft-landing load can be controlled from 18 to 55 N by adjusting the coil current from 0 to 0.8 A. Additionally, an impact force at the beginning can be eliminated using a modeled synchronous linear current, which indicates that the small-MRF damper has good soft-landing performance. Furthermore, the novel approach provides developing ideas for the miniaturization of the MRF damper.