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Skin is the largest organ of the human body and participates in the functional activities of the human body all the time. Therefore, human beings have a large risk of getting skin diseases. The diseased skin lesion image shows visually different characteristics from the normal skin image, and sometimes unusual skin color may indicate human viscera or autoimmune issues. However, the current recognition and classification of dermatological conditions still rely on expert visual diagnosis rather than a visual algorithm. This is because there are many kinds of lesion features of skin diseases, and the lesion accounts for a small proportion of the skin image, so it is difficult to learn the required lesion features; meanwhile, some dermatology images have too few samples to deal with the problem of small samples. In view of the above limitations, we propose a model named Lesion Area Aware Shifted windows Transformer for dermatological conditions classification rely on the powerful performance and excellent result of Swin transformer recently proposed. For brief notation, we use its abbreviation later. Our main contributions are as follows. First, we modify the Swin transformer and use it in the automatic classification of dermatological conditions. Using the self‐attention mechanism of the transformer, our method can mine more long‐distance correlations between diseased tissue image features. Using its shifting windows, we can fuse local features and global features, so it is possible to get better classification results with a flexible receptive field. Second, we use a skip connection to grasp and reinforce global features from the previous block and use Swin transformer to extract detailed local features, which will excavate and merge global features and local features further. Third, considering Swin transformer is a lightweight model compared with traditional transformers, our model is compact for deployment and more favorable to resource‐strict medical devices. [ABSTRACT FROM AUTHOR]

The ocean‐bottom currents are believed to be largely responsible for the high noise level in ocean bottom seismograph (OBS) data, in particular on the horizontal components. Due to the lack of in‐situ experiments and measurements, the generation mechanism and characteristics of the current‐induced noise are still poorly understood. In this paper, we designed an experiment to explore the features of current‐induced noise. A sensor module from a typical passive‐source OBS was installed in a water flume that can produce controllable steady water flows. We measured and analyzed the recorded noise with changing current velocities, with and without shielding. With other noise sources, such as infragravity waves precluded, this experiment demonstrates that the currents can generate low‐frequency noise, particularly <0.1 Hz. The noise level depends on the current velocity as well as the frequency. While the current‐induced noise affects the horizontal components significantly, its impacts on the vertical component appear negligible. The experiment shows that current‐induced noise has a dominant direction approximately perpendicular to the currents, a pattern consistent with an actual OBS on the flank of Mariana Trench, where the current direction is supposed to be along the trench. Shielding the sensor module with a plastic casing can substantially suppress the noise, indicating that shielding is a practical, low‐cost scheme to reduce the current‐induced noise. Key Points: Current‐induced noise exists in a wide frequency band; its level depends on the current velocity and the frequencyCurrent‐induced noise shows a dominant direction roughly perpendicular to currents, consistent with that at an actual ocean bottom seismograph in Mariana TrenchShielding the sensor can suppress the current‐induced noise substantially [ABSTRACT FROM AUTHOR]

This paper presents a new broadband ocean bottom seismograph (OBS) developed by the SUSTech OBS lab for passive-source seafloor seismic observations. This instrument, called Pankun, has several key features that set it apart from traditional OBS instruments. In addition to the seismometer-separated scheme, these features include a unique shielding structure to minimize current-induced noise, a compact gimbal for accurate leveling, and low power consumption for extended operation on the seafloor. The design and testing of Pankun's primary components are thoroughly described in this paper. The instrument has been successfully tested in the South China Sea, demonstrating its ability to record high-quality seismic data. The anti-current shielding structure of Pankun OBS has the potential to improve low-frequency signals, particularly on the horizontal components, in seafloor seismic data. [ABSTRACT FROM AUTHOR]

• An LGS electro-optically Q-switched Ho:GdVO4 laser operating at room temperature and directly pumped by LD is firstly reported. • The maximum output energy of 3.25 mJ with a pulse width of 4.2 ns were achieved at PRK of 1 kHz. • The peak power as high as 773.8 kW was achieved. We proposed a Ho:GdVO 4 laser operating at 2.05 µm in-band directly pumped by the 1.94 μm fiber-coupled laser diode, which electro-optically Q-switched by an LGS(La 3 Ga 5 SiO 14) crystal. Adopting 1.0 at.%-doped Ho:GdVO 4 crystal as the gain medium, a maximum output power of 6.5 W at 2047.9 nm with the absorbed pump power of 28 W was obtained in the continuous-wave mode, corresponding to a slope efficiency of 37.6 %. At a pulse repetition frequency of 1 kHz, the highest pulse energy of 3.25 mJ with a pulse width of 4.2 ns was achieved, corresponding to a peak power of 773.8 kW. In addition, the beam quality factor M2 was measured to be 1.9 at the maximum output level by the 90/10 knife-edge method. TEM 00 propagation has been verified by a camera. To the best of our knowledge, this is the first demonstration of high peak power electro-optically Q-switched Ho:GdVO 4 laser directly pumped by the 1.94 μm laser diode. [ABSTRACT FROM AUTHOR]

• High efficiency laser ultrasound of carbon fiber reinforced plastics is developed based on an annular distributed laser excitation source with wavelength of 2.09 µm. • The maximum ultrasound signal amplitude higher than 280 mV was realized. In this paper, we demonstrate a high-efficiency laser ultrasound in carbon-fiber-reinforced plastics (CFRP) by means of excitation laser spatial distribution modulation. The maximum ultrasound signal amplitude of about 286 mV was achieved by directing an annular laser with wavelength of 2090 nm, energy of 2.5 mJ and pulse width of 16 ns onto CFRP samples. The ultrasonic signal amplitude excited by annular laser is more than one times higher than that by typical Gaussian laser under the same conditions. Also, for CFRP laser ultrasound excited by annular laser, the intensity of ultrasound increased in different frequency components as a whole with increasement of laser energy density. The results indicated that it is an effective technical way to improve photo-acoustic efficiency and amplitude of the ultrasonic signal by shaping 2 μm region excited laser spatial distribution into annular type in the CFRP laser ultrasound. [ABSTRACT FROM AUTHOR]