This study demonstrated the enhanced conversion efficiency of an indium gallium nitride (InGaN) multiple quantum well (MQW) solar cell fabricated on a patterned sapphire substrate (PSS). Compared to conventional solar cells grown on a planar sapphire substrate, threading dislocation defects were found to be reduced from 1.28 × 109 to 3.62 × 108 cm−2, leading to an increase in short-circuit current density (JSC = 1.09 mA·cm−2) of approximately 60%. In addition, the open-circuit voltage and fill factor (VOC = 2.05 V; FF = 51%) of the solar cells grown on PSS were nearly identical to those of conventional devices. The enhanced performance is primarily due to improvements in the crystalline quality of the epitaxial layers, reducing the trapping of photogenerated electrons and holes by nonradiative recombination centers in MQW, with a corresponding increase in the transport efficiency of the carriers outside the device.

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The influence on coupling vibrations among shaft-torsion and blade-bending coupling vibrations of a rotor system with grouped blades was investigated analytically. The natural frequencies and the mode shapes of the system were solved with five- and six-blade cases used as examples. First, numerical results showed how the natural frequencies varied with the wire stiffness and the lacing wire mistuned. The diagrams of the coupling mode shapes were drawn. From the results, it was found that lacing wire did not affect the SB (shaft-blades) coupling modes, but the BB (inter-blades) modes were indeed affected by the lacing wire. At wire stiffness k*=10, the repeated BB modes split into more distinct modes. The BB modes were of (N-1) / 2 and N / 2 multiplicity for odd and even numbered blades. When the system has a mistuned lacing wire, it splits the BB modes and will once more have (N-1) frequencies. In the rotation effect, whatever tuned or mistuned, the lacing wires did not affect the instability. That means the instability preexisted due to rotation and was not induced by lacing wires.

A novel scheme of direct electrical contact on vertically aligned silicon nanowire (SiNW) axial p-n junction is demonstrated by means of oblique-angle deposition of slanted indium-tin-oxide (ITO) film for photovoltaic applications. The slanted ITO film exhibits an acceptable resistivity of 1.07 x 10⁻³Ω-cm underwent RTA treatment of T = 450°C, and the doping concentration and carrier mobility by Hall measurement amount to 3.7 x 10²⁰ cm⁻³ and 15.8 cm²/V-s, respectively, with an n-type doping polarity. Because of the shadowing effect provided by the SiNWs, the incident ITO vapor-flow is deposited preferentially on the top of SiNWs, which coalesces and eventually forms a nearly continuous film for the subsequent fabrication of grid electrode. Under AM 1.5 G normal illumination, our axial p-n junction SiNW solar cell exhibits an open circuit voltage of VOC = 0.56 V, and a short circuit current of JSC = 1.54 mA/cm² with a fill factor of FF = 30%, resulting in a total power conversion efficiency of PEC = 0.26%.

This paper aims to design an ultrasonic cleaning machine for crops to provide the engineers with very useful information. First, the new practical model is designed, including the body shell, cleaning tank, ultrasonic generator and control system. Second, three vegetables (lettuce, cabbage and potato) are used in the experiment. The result shows the damage percentage after washed was 0%. The root vegetables are cleaned faster in this machine.