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With the quickly development of the Internet of Things technology, Bluetooth (BLE) protocol has been increasingly adopted in consumer communication applications, industry communication utilization, and even positioning requirement, due to its advantages such as low power consumption, low cost, and low complexity. Especially the outstanding low power capability compared with other short-range communication protocol, many power limited AIoT (Artificial Intelligence IoT) devices select BLE as basic component. So, the low power, high performance, and small area BLE module become the key point of successful of whole AIoT system. In BLE system, the baseband data processing is the foundation. A good hardware circuit design of BLE baseband can improve BLE module performance and decrease power simultaneously. This paper analyzes the baseband data processing function of BLE in detail, and designs the baseband transmission data processing RTL circuit IP using Verilog HDL Hardware description language based on BLE protocol. The IP includes CRC verification module, whitening module and coding mapping function module. The RTL design is simulated and evaluated in workstation server with Synopsys VCS tool. The simulation results show that this design can achieve the Low-power BLE Bluetooth baseband function.

During the development of the stealth fighter, the S-shaped inlet enters the designer’s vision because it has better stealth than bump inlet and straight inlet. During the use of the S-shaped inlet, due to its structural reasons, secondary flow is likely to occur in the curved section, which directly causes the flow state to be changeable and complicated. Therefore, this paper takes the S-shaped inlet as the research object to analyzes the steady flow field simulation under uniform inlet condition and distortion inlet condition and analyze the flow field of the airflow and the total pressure of each section under the S-shaped inlet by changing the intake distortion conditions with CFX software. The results show that although the S-shaped inlet will occur total pressure distortion under uniform intake. However, when the S-shaped inlet work under certain flight conditions, the level of total pressure distortion will be smaller than the uniform inlet condition, which can improve the air intake performance. Finally, it can be inferred that with use of the S-shaped intake port, the deterioration of distortion may be prevented under certain specific intake conditions.

Along with the development of advanced high-performance aero-engines to the higher thrust-weight ratio, further improvement of stage load, the adoption of new materials and new lightweight structures, the aeroelasticity of blade structure is becoming more and more prominent. The high cycle fatigue failure of blades significantly reduces the structural reliability during the process of development and using. At the same time, a large number of failure forms of aero-engine experimental and server can be attributed to aeroelastic problems. Therefore, it is urgent to improve the aeroelastic stability of the blade. One of the most important factors is to suppress the airflow separation, but its mechanism is still unclear. Based on this, this paper combines the aerodynamic damping analysis of energy method with the plasma excitation simulation and references low-speed wind tunnel plasma expansion test to consider the effects of different exciter distributions and intensities on flutter. The results show that stall flutter is related to the flow separation, but the flow separation is not a key factor that determinates whether the flutters occurs or not. Flutter suppression is strongly correlated with the shock wave intensity, amplitude of first harmonic aerodynamic force, low-speed separation and aerodynamic work density. In addition, the relative distribution of the excitation field and the positive work zone also has a direct effect on the suppression of flutter.

Polylactic acid (PLA) / polyolefin elastomer (POE) / modified starch composites were prepared by melt blending. The composites were characterized by softening point, polarizing microscope, melt flow rate, tensile strength and degradation properties. The results showed that with the increase of modified starch and POE content, phase separation occurred between modified starch and PLA, and the tensile strength decreased compared with pure PLA. Modified starch could increase the crystallinity of PLA to increase the softening point and improve the thermal stability of PLA. When the modified starch and POE content were 15 and 20 parts respectively; the composite material has the best performance. At this time, the softening point was 75°C and the tensile strength could reach 47.7 MPa. The composite materials in different media showed the quality decreased with the prolongation of degradation time, especially in acidic and alkaline conditions, because the degradation rate of hydrolysis was accelerated.