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Due to the diversity of scales and shapes, the uncertainty of object position, and the complexity of edge details, the recent merging problem of salient object detection in optical remote sensing image (RSI-SOD) is a considerably challenging topic. To cope with the challenges, we propose a new cross-scale interaction network (CIFNet) equipped with the enlarged receptive field, which mainly contains three modules in an encoder–decoder architecture, including a furcate skip connection module (FSCM), a global leading attention module, and an expansion–integration module (EIM). First, the FSCM uses dilated convolutions to enlarge the receptive field and furcate skip connections to capture more multiscale contextual information, both of which facilitate the adaptability of the model to different sizes, shapes, and quantities of the target objects. Second, on the low-resolution branch, a global leading attention module (GLM) locates the potentially significant object positions in the feature map from a global semantic perspective. Finally, through an attention-guided cascade structure, the EIM seeks more delicate characteristics by refining the features in a coarse-to-fine fashion. Extensive experiments are conducted on two RSI-SOD datasets, from which superior results can be achieved by our CIFNet, outperforming the other state-of-the-art methods. Compared with the second-best method, the performance gain of our method reaches 3.45% on mean absolute error (MAE) and 1.38% on $F_{\beta} ^{\mathrm {adp}}$. Notably, the proposed CIF-Net runs with 40.40-M parameters, 14.8-GFLOPs computational complexity, and 58-frames/s inference speed, which guarantees high efficiency. [ABSTRACT FROM AUTHOR]

Existing tensor-based coherent direction-of-arrival (DOA) estimation methods adopting spatial smoothing to decorrelate the coherent tensor statistics usually lead to a poor decorrelation performance. In this letter, we propose a structured tensor reconstruction method for two-dimensional coherent DOA estimation, which then avoids the inefficient spatial smoothing. In particular, after investigating the structural property of the four-dimensional incoherent covariance tensor, we propose a tensorial Hermitian Toeplitz mapping rule to reconstruct a structured covariance tensor from the rank-deficient coherent covariance tensor statistics. It is theoretically proved that, the reconstructed covariance tensor admits a decorrelated canonical polyadic model with a tensorial Hermitian Toeplitz structure, whose decomposition ensures a closed-form coherent DOA estimation. The effectiveness of the proposed method is verified by simulations. [ABSTRACT FROM AUTHOR]

Epitaxial growth of CeO2 buffer layers on biaxially textured (001) Ni tapes was studied using reel-to-reel pulsed laser deposition. Relationship between microstructure and deposition parameters was systematically studied in order to develop reliable long tape coating processes. Prior to buffer layer deposition, Ni tapes were in situ annealed in forming gas (97% argon + 3% hydrogen) under various pressures and tape speeds to accelerate reel-to-reel annealing processes. It was found that orientation and texture of CeO2 buffer layers were sensitive to deposition parameters. X-ray diffraction analyses showed that CeO2 buffer layers had pure (001) orientation at forming gas pressure of 5 mTorr and 700°C. Under optimized deposition conditions, highly (001) oriented CeO2 buffer layers have been achieved at a high tape speed of 20-50 m/h. In-lane texture of CeO2 buffer layers was 7 degree which was comparable to the value of Ni tapes. [ABSTRACT FROM AUTHOR]

This letter proposes a multiple-beam Cassegrain antenna with quasi-optical isolator at 200 GHz for target tracking. The proposed antenna is designed with a special topology, in which a multichannel transceiver feed integrated with a quasi-optical isolator is designed and placed in the back of the main reflector, aiming to isolate the transmitting and receiving channels, and to avoid the aperture blockage. Four receiving feeds are laterally defocused to produce offset beams and each of them is received and sampled individually without comparators, which simplifies the structure and provides flexibility for signal processing. An optimization is performed to achieve the best compromise design considering the conflicts induced by its special structure. The fabricated antenna is measured and the results demonstrate an excellent radiation performance of the proposed antenna. Four well-performed offset beams are obtained as expected and the antenna works stably within a bandwidth of 10 GHz. The measured 3 dB beamwidths vary around 0.6° and the sidelobe levels are lower than −12.5 dB for all the beams. The superiorities of the proposed antenna show its potential application in high-performance tracking and imaging systems. [ABSTRACT FROM AUTHOR]

Heat-assisted magnetic recording (HAMR) is a technique for overcoming the superparamagnetic limit and enabling large increases in the storage density of hard disk drives. A tiny area of the magnetic recording media has to be heated up to a high temperature with a laser to lower the coercivity temporarily before information can be written on the area. The possible degradation of the ultrathin media carbon overcoat induced by the laser heating is a concern. In this paper, the laser heating-induced degradation of ultrathin a-C:Nx, a-C:Hx, and a-C overcoats on HAMR media is studied. Surface topography changes induced by the laser heating are evaluated with atomic force microscopy and structure changes with the visible Raman spectrum and X-ray photoelectron spectroscopy (XPS). Laser heating areas are analyzed with time-of-flight secondary ion mass spectrometry and XPS to reveal the underlying mechanism of the degradations. It is found that at a proper HAMR writing temperature and for a total laser heating duration corresponding to a five-year drive life, the surface topography, structure, and composition of the a-C:Nx overcoat are changed by the laser heating. However, the surface topographies of the a-C:Hx and a-C overcoats are not changed. The structure and composition of the a-C:Hx and a-C overcoats are also not changed much. Interlayer diffusion between the carbon overcoat and the underlying magnetic layer is confirmed in the laser heating area for all the three overcoats. [ABSTRACT FROM AUTHOR]