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AbstractElectroencephalogram (EEG) signals, which objectively reflect the state of the brain, are widely favored in emotion recognition research. However, the presence of cross-session and cross-subject variation in EEG signals has hindered the practical implementation of EEG-based emotion recognition technologies. In this article, we propose a multi-source domain transfer method based on subdomain adaptation and minimum class confusion (MS-SAMCC) in response to the addressed issue. First, we introduce the mix-up data augmentation technique to generate augmented samples. Next, we propose a minimum class confusion subdomain adaptation method (MCCSA) as a sub-module of the multi-source domain adaptation module. This approach enables global alignment between each source domain and the target domain, while also achieving alignment among individual subdomains within them. Additionally, we employ minimum class confusion (MCC) as a regularizer for this sub-module. We performed experiments on SEED, SEED IV, and FACED datasets. In the cross-subject experiments, our method achieved mean classification accuracies of 87.14% on SEED, 63.24% on SEED IV, and 42.07% on FACED. In the cross-session experiments, our approach obtained average classification accuracies of 94.20% on SEED and 71.66% on SEED IV. These results demonstrate that the MS-SAMCC approach proposed in this study can effectively address EEG-based emotion recognition tasks. [ABSTRACT FROM AUTHOR]

As the demand for high-performance dissimilar material joining continues to increase in fields such as aerospace, biomedical engineering, and electronics, the welding technology of dissimilar materials has become a focus of research. However, due to the differences in material properties, particularly in the welding between metals and non-metals, numerous challenges arise. The formation and quality of the weld seam are strongly influenced by laser process parameters. In this study, successful welding of high-borosilicate glass to a TC4 titanium alloy, which was treated with high-temperature oxidation, was achieved using a millisecond pulsed laser. A series of process parameter comparison experiments were designed, and the laser welding behavior of the titanium alloy and glass under different process parameters was investigated using scanning electron microscopy (SEM) and a universal testing machine as the primary analysis and testing equipment. The results revealed that changes in process parameters significantly affect the energy input and accumulation during the welding process. The maximum joint strength of 60.67 N was obtained at a laser power of 180 W, a welding speed of 3 mm/s, a defocus distance of 0 mm, and a frequency of 10 Hz. Under the action of the laser, the two materials mixed and penetrated into the molten pool, thus achieving a connection. A phase, Ti5Si3, was detected at the fracture site, indicating that both mechanical bonding and chemical bonding reactions occurred between the high-borosilicate glass and the TC4 titanium alloy during the laser welding process. [ABSTRACT FROM AUTHOR]

The authors describe the process whereby a student with a background in economics was guided to understand the central role in qualitative research of the researcher as instrument. The instructor designed a three-part mock research project designed to provide experiential knowledge of the enterprise of qualitative research. Students, as neophyte qualitative researchers, were guided to develop a sophisticated understanding of the necessity for congruence between the ontological and epistemological philosophical underpinnings of the research question, data collection techniques, and analysis. An example of the trail of analytic decisions one student made during analysis is included to show the complexity of qualitative analysis and interpretation. (Contains 3 tables and 1 figure.)

Large-size β-Ga2O3 single crystals without sub-grain boundaries and cracks were grown by the optimized EFG technology. The thermal volatilization of Ga2O3, polycrystalline growth and cracking were systematically characterized and analyzed from phenomenological and crystallographic points. The proportion of CO2 gas in the growth atmosphere and axial temperature gradient of the thermal field play important roles in suppressing the thermal decomposition and volatilization of a Ga2O3 melt. A higher seeding temperature could effectively inhibit polycrystalline growth. Furthermore, the effects of annealing in an oxygen environment on the optical properties of β-Ga2O3 crystals were discussed. [ABSTRACT FROM AUTHOR]

High-quantity and large-size β-Ga2O3 single crystals were grown by the optimal edge-defined film-fed method. Under the excitation of 241Am α-ray, the scintillation light yields of the as-grown and after-annealed β-Ga2O3 single crystal are estimated to be 4797 and 6788 ph/5.5 MeV-α, respectively. The energy resolutions of the as-grown and after-annealed β-Ga2O3 single crystal are 21.8% and 19.1%, respectively. Annealing in the air can eliminate some color centers and decrease the concentration of free electrons, which can lead to the near-infrared absorption. The light yield and the energy resolution are some slightly worse than that of the commercial Bi4Ge3O12 (BGO) scintillator. However, the fast component with the time constant of 7 ns for the as-grown and after-annealed β-Ga2O3 single crystal reaches 25% of the total yield, suggesting that the β-Ga2O3 single crystal grown by the present method is a promising fast scintillator, which could be used in the ultrafast timing resolution detection systems. [ABSTRACT FROM AUTHOR]

We investigated the temperature-dependence of X-ray excited luminescence of β-Ga2O3 single crystals. The recombination of free-electrons with self-trapped holes (STHs) responsible for the ultraviolet luminescence (UVL) band was observed. For the as-grown sample with a high electron concentration, the Auger recombination becomes important, which accelerates the decay dynamics and reduces the ultraviolet luminescence band. The ultraviolet luminescence band is controlled by temperature quenching due to the migration of self-trapped holes to VGa3− centers. Annealing in an oxygen environment can increase the VGa3− concentration, which contributes to the blue-green luminescence band when VGa3− captures a self-trapped hole forming a VGa2− center at rising temperature. [ABSTRACT FROM AUTHOR]

Abstract: Controllable and repeatable crystal imperfection modulation engineering (CIME) is important for the development of semiconductor science and technology. However, for wide band gap semiconductors (WBGSs), there still lacks universal and reliable CIME. Here, based on the general idea of chemical composition complete expression design, a well‐designed, repeatable, and feasible CIME for ZnO is introduced, making free modulation of carrier in WBGS become possible. Briefly, this extraordinary CIME is dominated by two innovative procedures: an electrochemical doping and a strong oxidizing atmosphere annealing. The proposed CIME is a repeatable and universal carrier modulation project, which holds technological promise for various WBGS‐based semiconductor devices. Benefiting from this CIME, an α particle detector which operating at a high electric field of 107 V cm−1 can be fabricated successfully. [ABSTRACT FROM AUTHOR]