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To address the problems of low accuracy of existing deep learning-based micro-expression recognition models, numerous network parameters, and the difficulty of mobile deployment of micro-expression recognition models, this paper proposes DCBAM-EfficientNet, a micro-expression recognition model that uses the lightweight network EfficientNet as the backbone network and incorporates the attention module. The network can guarantee the accuracy of micro-expression recognition with relatively few network parameters. The attention mechanism allows the more expressive micro-expression features to be highlighted, and the CBAM attention is improved into a DCBAM model, where the large convolution kernel in the spatial attention module of CBAM is replaced by a dilated convolution with the same receptive field, reducing the network parameters while better preserving the spatial features of the image. The integration of the DCBAM model into the main structure of EfficientNet enables better integration of contextual information. Data enhancement is used to process the micro-expression dataset to decrease the occurrence of overfitting and improve the generalization ability of the model. The results demonstrate that the optimized model DCBAM-EfficientNet can effectively promote the recognition accuracy of micro-expressions, significantly reduce the quantity and volume of model parameters, and provide a reference for the deployment of mobile micro-expression recognition models.

This paper reports that the growth of RuO2(110) thin layer growth on Ru(0001) has been investigated by means of scanning tunnelling microscope (STM). The STM images showed a domain structure with three rotational domains of RuO2(110) rotated by an angle of 120°. The as-grown RuO2(110) thin layer is expanded from the bulk-truncated RuO2(110) due to the large mismatch between RuO2(110) and the Ru(0001) substrate. The results also indicate that growth of RuO2(110) thin layer on the Ru(0001) substrate by oxidation tends first to formation of the Ru-O (oxygen) chains in the [001] direction of RuO2(110).

Rb3C60 single-crystal thin films were prepared on the cleaved (111) surface of C60 single crystal. The photoemission spectrum line shapes of the lowest unoccupied molecular orbital (LUMO) derived band at room temperature and 150 K were established by synchrotron radiation photoemission spectrum measurements. The density of states near the Fermi level was distinctly affected by temperature. No less than six sub-peaks of the LUMO band were observed even at room temperature. The existence of so many sub-peaks offered the opportunities to analyse in more detail the orientational structure and the electron-Boson interactions of the narrow-band metallic Rb3C60.

We report the results of first-principles calculations on the electronic structure in ferromagnetic and non-magnetic hexagonal MnV (V = As, Sb, Bi). The calculations are based on the local-spin-density approximation (LSDA) of the density-functional theory (DFT) as well as the atomic sphere approximation (ASA) in the linear muffin-tin orbitals (LMTO) method. For the non-spin-polarized case, the calculated bands in these compounds exhibit p-d mixing in the vicnity of Fermi energy and the Mn 3d bands dominate the antibonding parts of p–d hybride. The spin-polarization in ferromagnetic states are mainly due to the splitting of anti-bonding bands from p–d mixing. The calculated spin moments in these compounds agree fairly well with experimental values and refine previous band calculations. In the spin-polarized band structure, the Mn 3d electrons are found to exhibit week dispersions.

Electron band structure of C60 single crystal has been investigated using synchrotron radiation. On the cleaved (111) surface of the C60 single crystal the angle-resolved ultraviolet photoelectron spectra were measured at normal emission with varying photon energy from 12.7 to 28.2 eV. The valence band dispersions in L-Γ-L direction were successfully observed. The dispersions are 0.14 and 0.17 eV for the highest occupied molecular orbitals (HOMO) and HOMO-1 derived band respectively.

Ultra-violet photoemission spectroscopy measurements for CO adsorption on the (2×2)-Cs precovered Ru (0001) surface were performed. The Cs 5p (5p3/2) level (Cs state) locates at 11.3 eV in binding energy for the (2×2)-Cs overlayer on Ru (0001). Upon the CO adsorption, a new peak, which is associated with the Cs 5p state for the Cs adatoms influenced by the neighbouring CO adsorbed (the Cs+CO state), appears at the lower binding energy side of the Cs state. This new peak is at 10.8 eV for the CO saturation where the (2×2)-Cs+2CO compound layer is formed. This result gives clear evidence for local interaction of Cs and CO on the Ru (0001) surface. PACS: 73. 20. At, 82. 65. My, 68. 35. Bs

We prepare a well-defined C84 monolayer on the surface of Ag (111) and study the geometric structure by scanning tunneling microscopy (STM). The C84 molecules form a nearly close-packed incommensurate R30° lattice. The lattice is long-distance ordered with numerous local disorders. The monolayer exhibits complex bright/dim contrast; the largest height difference between the molecules can be greater than 0.4 nm. Annealing the monolayer at 380 °C can desorb part of the molecules, but more than sixty percent molecules stay on the Ag (111) surface even after the sample has been annealed at 650 °C. Our analyses reveal that the 7-atom pits form beneath many molecules. Some other molecules sit at the 1-atom pits. Ag adatoms (those removed substrate atoms, accompanying the pit formation) play a very important role in this system. The adatoms can either stabilize or destabilize the monolayer, depending on the distribution manner of the adatoms at the interface. The distribution manner is determined by the co-play of the following factors: the dimension of the interstitial regions of the C84 overlayer, the number of the adatoms, and the long-distance migration of part adatoms.

A symmetry plane for K-CO co-adsorbate at low coverage on Fe(110) surface was found using angle-resolved UPS with polarized light. This plane is parallel to the 110 azimuth of the crystal surface. The dependence of the CO 4σ peak intensity on incidence angle was found to be nearly the same as in the case without K, where the molecular axis of CO is perpendicular to the surface.

The geometric and electronic structures at the interface between iron phthalocyanine (FePc) and Si(110) surface are studied by ultraviolet photoelectron spectroscopy and density functional theory (DFT) calculation. After FePc is deposited on Si(110), the emission features are located at 2.56, 4.90, 7.90, 10.88 eV below the Fermi level for monolayer and 2.73, 4.90, 7.74, 10.52 eV below the Fermi level for multilayer. At the coverage of 1 ML, FePc molecules are adsorbed on the bridge site in a flat-lying geometry with a 2.17 A separation between the molecule and the substrate. The molecular plane is bent due to the interaction between the adsorbate and the substrate.

We present the simple designs of metamaterial absorbers which are composed of a periodic array of copper annular (or circular) patches, FR4 substrate, and copper film. With appropriate geometrical parameters, these metamaterials can provide the electric and magnetic resonances overlapping in the given frequency range, and the experiments demonstrate the absorptivities of 97.6% and 96.7% with only a single layer of the metamaterial absorber. The surface currents and field distributions of these metamaterials are discussed to look straight into the resonance mechanism. Furthermore, our numerical simulations confirm that these metamaterial absorbers could be operated at wide angles of incidence. The simple and highly symmetric structures of the metamaterial absorbers proposed would greatly accelerate the practical applications in optics and electromagnetics.