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5A06 aluminum alloy and DP1180 ultrahigh-strength steel dissimilar metals were joined by plasma arc welding with AlCu6 welding wire. The interface of AlCu6 weld/steel joint was characterized by SEM, electron backscatter diffraction (EBSD) and focused ion beam-transmission electron microscopy (FIB-TEM). The results revealed that Fe–Al intermetallic compounds (IMCs) layer with double structure was formed at AlCu6 weld/steel interface, which were Fe4Al13layer with needle-like shape and Fe2Al5layer with tongue-shape. Fe2Al5grains exhibited a clear preferential orientation in the [001] crystal direction and a strong silk texture in the <001> direction, but were weaker in Fe4Al13grains. The average Schmidt factor of the Fe4Al13and Fe2Al5grains in the interface zone was 0.269 and 0.287, respectively, corresponding to the high brittleness and hardness of Fe4Al13and Fe2Al5. The maximum tensile strength of the joints was 118.0 MPa and the aluminum/steel joints all fractured at the interface zones. The brittle IMCs of Fe4Al13and Fe2Al5played a crucial role in contributing to the joint fracture.

Visual hand gesture interaction is one of the main ways of human-computer interaction, and provides users more interactive degrees of freedom and more realistic interactive experience. Authors present a hybrid model based on SVM-LSTM, and design a three-dimensional dynamic gesture interaction system. The system uses Leap Motion to capture gesture information, combined with SVM powerful static gesture classification ability and LSTM powerful variable-length time series gesture processing ability, enabling real-time recognition of user gestures. The gesture interaction method can automatically define the start and end of gestures, recognition accuracy reached 96.4%, greatly reducing the cost of learning. Experiments have shown that the gesture interaction method proposed by authors is effective. In the simulated mobile environment, the average gesture prediction only takes 0.15 seconds, and ordinary users can quickly grasp this method.

Net first and second dipole reflections are computed for several finite and infinite arrays of cylinders or spheres held stationary in a uniform potential flow. The polarizability and resistivity, from which the macroscopic properties of a two-phase flow with corresponding microstructure can be derived, are deduced for the infinite arrays. Finite arrays resemble infinite ones apart from edge and end effects, which are small for some geometries. The added mass coefficient for a regular monolayer of spheres is obtained and shown to be very close to Smythe's (1964) solution for a sphere in a circular tube. Similar agreement is obtained between the solutions for a cubical array of spheres and for a row of spheres in a circular tube.

To solve the problem of solid waste pollution generated during the Ecological Rural Construction in China, the products obtained from composting were used for garden utilization on the premise of mixed compost product treatment of rotten garbage in rural areas. The results showed that the solid waste compost products had good biosafety and fertilizer efficiency in the growth of landscaping plants such as woody flowers, herbaceous flowers, turf plants and foliage plants. The experimental plants could not only survive in the soil containing compost products, but also grow well, significantly better than growing in the garden soil.