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This work is intended to describe the design aspects and to characterize the functionality of a novel flip-chip (FC) structure applicable for THz camera assembling. The proposed FC structure consists of a thin-film ceramic layer sandwiched between a GaAs substrate and PCB board. There is an air chamber underneath the antenna to protect the air bridge of Schottky Diode located on GaAs substrate and improve antenna performance. In particular, we have used the novel FC structure simulation result as the excitation source for THz camera lens simulation. Even if the FC structure cause antenna performance to deteriorate, the high gain can be obtained at 0.34 THz and 0.22 THz (λ = 880 and 1360 μm) from the FEKO simulation results. The FC structure mode and the without FC structure (wire bonding structure) mode were characterized using same test system, they show good match in proposed frequency range.

According to the principle and mathematical model of doubly-fed induction generator (DFIG), the rotor current is first analyzed under blade mass imbalance, and then the stator current characteristics is deduced based on the dq coordinate system transformation. At last, use the rotor and stator current Hilbert envelope demodulation (HED) method to diagnose the fault of blade mass imbalance. In order to verify the effectiveness of the theoretical analysis, the simulation analysis is carried out under Matlab/Simulink environment firstly. Then the experiment on a wind turbine experiment platform is carried out. Simulation and experimental results show the correctness of the proposed method in this paper.

To research the inherent properties of the co-expression of three types degumming-related enzymes and breed more powerful degumming strains. Six tandem multimers of the pectate lyase gene, the xylanase gene, and the endo-1,4-β-mannanase gene, which are essential for degumming process, were co-expressed and evaluated in Escherichia coli BL21(DE3). The xyl91 gene had a synergistic effect with endo-1,4-β-mannanase and pectate lyase from DCE-01, when xyl gene was replaced with xyl91 in the multimer. The recombinant pET-pxm(91x) was selected and transformed into the original degumming strain DCE-01, which led to an enzymatic activity improvement. Furthermore, the weight loss, reducing sugar and COD value of the sample treated with the new engineered strain pET-pxm(91x)/DCE-01 increased to 22.5 %, 460 mg ml−1 and 4.9, respectively. The co-expression of degumming-related enzyme genes may be applied in industrial tests and represents a novel direction for bio-degumming research.