In order to scientifically and reasonably evaluate and select the quality and effect of ecological slope protection construction project and the structural form of ecological slope protection, this paper mainly studies nanomontmorillonite modified fly ash ecological slope protection material and its preparation method and related applications. The nanomontmorillonite modified fly ash ecological slope protection material and its application in this paper are based on nanomontmorillonite modified fly ash as the basic carrier, and the pore structure is used to plant grass for slope protection to achieve the purpose of ecological slope protection. Firstly, the nanomontmorillonite modified fly ash ecological slope protection material was prepared through the selection of raw materials, the mix ratio design, and the reasonable selection of the preparation process, and the range analysis method was used to optimize the mix ratio of nanomontmorillonite modified fly ash. By reasonable selection of alkali-reducing measures, selection of slope protection vegetation, preparation of planting substrates, and research on phytobiology, through experimental analysis, we obtained nanomontmorillonite modified fly ash with high strength and good water permeability and alkalinity in the pores to meet the requirements of plant growth ecological slope protection materials. Finally, through engineering practice, we explored the construction method of nanomontmorillonite modified fly ash ecological slope protection material and obtained good ecological slope protection benefits. The experimental data show that, for dispersive soil, when the degree of compaction is 80%, the compressive modulus of the soil is 3.46 MPa; when the degree of compaction is 86%, the compressive modulus of the soil becomes 4.51 MPa, an increase of 46.57%. The experimental results show that the nanomontmorillonite modified fly ash ecological slope protection material can help the soil become more compact.

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Whether launching from the ground or in the air, hypersonic vehicles need the booster to accelerate to a predetermined window, so as to meet the requirements of scramjet engine ignition. Therefore, there is interference suppression between boosters and hypersonic vehicles under the high dynamic pressure, which has become a key technical problem that affects the success of flight tests, especially when the aircraft is statically unstable. A method of variable structure switching-based control is proposed in this paper for rapid suppression on hypersonic vehicle booster separation interference. Switching control systems in real time according to state changes caused by flow field interference, the method can keep the attitude stability of hypersonic vehicle booster separation under the high dynamic pressure of static instability. The aerodynamic calculation model of the hypersonic vehicle booster separation process is established first, which adopts an unsteady solution and clarifies the aerodynamic interference characteristics of the afterbody on the vehicle in booster separation. Then, according to the characteristics of the flow field, the dynamics of the vehicle in and out of the interference area are converted into subsystems with switching characteristics. Using the dimension reduction and variable structure method, the switching control surface of the control system is established. On the basis of the vehicle state changes caused by flow field, the control system on the orbital change surface can be switched in real time to achieve stable attitude in the process of separation interference. Meanwhile, considering the additional interference torque generated by the afterbody to the vehicle in the separation process, a control system for interference suppression of the booster separation is designed. Simulation results verify that the designed control system can rapidly suppress the booster separation interference when the dynamic pressure is about 150 kPa and the vehicle has the static instability of 5%, thereby realizing the stable attitude of the vehicle.

Whether the test of free-flight stall/spin can be carried out successfully, it depends on the airborne anti-stall parachute system, the performance indexes of the system are related to the test pilots’ safety directly. There are large numbers of test signals in the system and half of them are transient pulse signals, so it requires high real-time capability and data throughput level. Thus the danger of the Ignition testing experiment, Telemetry Tracking Monitoring is requisite. To satisfy the need of measuring electric parameters of an airborne anti-stall parachute system, a multi-thread real-time DAQ system of multi-task is constructed, using dual-core industrial computer and high-speed DAQ card as its core, LabWindows/CVI as VI software platform. By a method of dual-core parallel processing through OS kernel, system accomplishes multi-channel data acquisition with high real-timing and huge data throughput, and through TCP/IP, ODBC interface, remote measurement and database management is also accomplished. At the last, the system design a modularize software by DLL technology, packaging several functional modules in DLL form. This system implements the multi-thread mechanism and its synchronization, TCP/IP communication and parallel processing under LabWindows/CVI platform. Finally high real-timing and reliability of this system are validated by experiment.

Hypersonic vehicles often use the aerodynamic configuration and light materials such as lifting body and waverider, which leads to the unmatched uncertain control problems caused by strong coupling characteristics and interference during reentry. To solve these problems, firstly, this paper analyzes the key factors and uncertainties that affect the attitude motion of hypersonic vehicle. Secondly, it studies the modeling and verification of rigid body and elastic body of hypersonic vehicle, establishes the error model with disturbance observation compensation, and proposes a new attitude control scheme of hypersonic vehicle, which realizes the stable tracking of attitude angle and improves the uncertainty of key parameters of the system. The simulation results show that the performance index meets the requirements and has good robust performance in the presence of unknown disturbance.