The combination between hydrophilic extracellular matrix polysaccharides and hydrophobic aliphatic polyesters is a challenge in the biomaterial field. Here we investigated the formation of chitosan/polylactic acid (CS/PLA) composites using a novel emulsion freeze-drying technique, in which CS soluti...

One of the most important factors to depress the accuracy of position tracking is the internal and external uncertainties always existing in the system. Due to its strong robustness, sliding mode control can effectively eliminate the impact of uncertainties yet with the trouble named chattering. The...

To solve the problem that the confidence on the estimate is poor when the dynamic Allan variance is used to analyze stochastic error of gyro, due to the reduced amount of data captured by the truncation windows, a new algorithm based on high confidence and hybrid theoretical variance (TheoH variance...

An improved constant-frequency digital hysteresis current control strategy (HCCS) was introduced for high-power 20 kW brushless DC motor used in airborne integrated electrical hydrostatic actuator (EHA). In this control strategy, by the modeling of phase current using PWM_ON modulation mode and anal...

Some related questions in system equipment configuration under unsteady state and multi-constraint are discussed. First, taking the very low utilization rate of escort equipment in the waters off Somalia as study background, the paper presents the solution to base and central warehouse spare parts d...

The fluid-structure coupling deformation of the parafoil was numerically simulated under steady condition. The finite volume method was used to compute the aerodynamic load, and the effect of leading-edge cut and ribs on the pressure distribution was analyzed simultaneously. Nonlinear cable-membrane...

Probability hypothesis density (PHD) filter has been demonstrated to be an effective approach for multi-target tracking in real time. However, these methods based on the PHD filter assume that the measurement noise covariance is known as a priori. This is unrealistic for real applications because it...

This paper studies the working principle of the differential piston warm gas self-pressurization system of liquid attitude and divert control engines working with monopropellant-hydrazine, based on which a parametric design method and the corresponding design process of the system parameters are pre...

In order to meet the rapid analysis requirements of launch dynamics, the absolute coordinates method of rigid multibody dynamics was used to fit the characteristics of complex constraints and changing topological structure of the vehicular launch systems. A fast simulation model with nine degrees of...

A locating method of near distance electromagnetic radiation source is proposed in this paper. To avoid the disadvantages of complexity, high hardware cost and large volume of the conventional multi-channel array system, a single antenna motion virtual array system is proposed to realize the functio...

The traditional BPM semi-empirical prediction airfoil turbulent boundary layer trailing edge noise was improved. The traditional BPM semi-empirical prediction formulation overpredicts the spectra in high frequency range at high angle of attack or for thick airfoil. It is found that it was mainly cau...

As a kind of compliance control method, impedance control can realize force and position coordination control. So it has obvious advantages in the applications that the actuating systems are required to interact with the environments. Because of high energy efficiency and compact structure, electro-...

In order to improve the measurement precision and reduce the influence of equipment under test (EUT) electromagnetic radiated emission testing location on test results in electromagnetic capatibility (EMC) semi-anechoic chamber, this paper studies the influence law on electromagnetic signal radiatio...

According to the length and the inlet boundary conditions of injector, the gas-liquid coaxial injectors of liquid rocket engine are simplified into four categories:1/4 wavelength closed tube, 1/2 wavelength closed tube, 1/4 wavelength open tube and 1/2 wavelength open tube. Linear acoustics is adopt...

To solve the problems of overlapping and difficult separation of micro-Doppler information of multi-ballistic target echo in narrow-band radar, a novel method based on auction algorithm and wavelet analysis is proposed to separate micro-Doppler of multi-ballistic targets. First, based on the sliding...

Aimed at vehicle-mounted strap-down inertial navigation system (SINS), a rapid coarse alignment method for marching vehicle is proposed. The matrix between navigation frame and body frame is decomposed into three parts. The problem to solve the matrix between navigation frame and body frame is attri...

Vortex shedding from a circular cylinder with a slit which belongs to the unsteady flow of bluff bodies has very strong application prospects. However, it is still difficult to fully understand the complex flow phenomenon. Using flow visualization and particle image velocimetry (PIV) measurement, we...

In order to study the dynamic load characteristics, the multi-axle vehicle powertrain system dynamics simulation model was developed. First, the engine dynamic characteristic model was built by obtaining the cycle fuel injection quantity-rotate speed-torque MAP according to the load characteristic t...

A new crossbar buffer balanced scheduling algorithm called multicast and unicast crossbuffer balance (MUCB) is proposed for combined input and crossbar queued (CICQ) architecture switches, which accommodates mixed unicast and multicast traffic. Different from the popular algorithms mainly based on t...

Based on the solution algorithm of state equation in modern control theory, analysis and comparison between interval analysis method and stochastic process are proposed to solve control system with uncertain but bounded parameters. After the definition and influence of uncertainty in engineering pra...

Due to the large interference torque of deflected cylindrical magnetic bearing, this paper designs a novel electromagnetic radial spherical magnetic bearing. When the spherical bearing deflects or offsets, the electromagnetic force will keep pointing to the center of the rotor, which can reduce the ...

In order to solve the problem of the existing dynamic fault tree analysis method, such as state space explosion, low computational efficiency and limited application range, a method for dynamic fault tree analysis based on sequential binary decision diagram is proposed. First, dynamic logic gates ar...

Before the localization operation, the serial robot position relationship between base coordinate system and measurement coordinate system needs to be demarcated. For the hidden robot base and flange coordinate systems of serial mechanism, a kind of equivalent transformation method is presented in t...

Flying wing configuration aircraft is advantageous on the characteristics of stealth and aerodynamics, but due to lack of conventional elevator and rudder, gust alleviation control method for the aircraft with conventional configuration is not suitable anymore. For the flying wing configuration airc...

To monitor the oil spill situation in small-scale fixed sea area, a shore-based sea surface oil spill detecting method was developed using BeiDou reflected signal. This method applies/global navigation satellite system-reflection (GNSS-R) technology to shore-based oil spill detection. A shore-based ...

It is a superior new closed-loop simulation method to introduce reaction wheels' real-time torque acquired by a torque measuring system into satellite semi-physical simulation. However, due to the sustained external torque introduced into the simulation closed loop, the semi-physical simulation coul...