Chunling Yang

Research on infrared decoy radiation characteristics and simulation

Infrared decoy is a common method of infrared countermeasures. In order to research the corresponding anti-interference strategy, it is essential to establish an IR decoy radiation model. This paper researches on the radiation characteristics of IR decoy, probes into the flow field of IR decoy, then establishes a relatively accurate radiation characteristics model for the IR decoy exhaust plume, at last, simulates the model based on computer simulation which provides the basis for further research on the IR decoy.

A testability allocation method based on Analytic Hierarchy Process and comprehensive weighted

Testability allocation is an important process in design for testability, which allocates system-hierarchy testability index hierarchy by hierarchy down to every part of the system. Aiming at the shortage of the existing testability allocation methods, an unconventional allocation method based on Analytic Hierarchy Process (AHP) and comprehensive weighted method is proposed in this paper. On the basis of testability model of system, comprehensive weighted method is used to take use of the influence parameters and weighting coefficients of each unit of the system calculated by Analytic Hierarchy Process to solve allocation values of each unit. Compared with others, this allocation method is simple, requires less calculation and satisfies different demands. This method is applied to a system to verify its validity, the results show that it is able to effectively integrate various influencing factors and reasonably allocate testability index of the system down to units.

The study of novel chaotic oscillator detecting weak signal amplitude

Nowadays the traditional detecting method of weak signal amplitude is to use Duffing system. However it is limited in actual engineering application. Its structure is very simple but its dynamic characteristics are very complex. There are a lot of chaos oscillators being used to detect unknown signal so that the detection method is too complex. In this paper the dynamic characteristics of Lorenz system are studied. And the Lorenz chaotic oscillators are applied in amplitude detection of weak signal which is submerged in strong noise. Through phase diagram analysis and chaotic orbits change the unknown amplitude of weak signal is obtained. The research purpose is to find a new detection method of weak signal amplitude. The simulation results verified that the presented method is feasible and effective. It is lower to detect the signal to noise ratio than those of Duffing system.

A novel approach based on spectral-temporal information fusion for multi-target detection

This paper describes a novel particle filter-based track-before-detect (TBD) technique for multiple dim moving targets with fluctuating intensity in multi-spectral IR image sequence. The proposed approach consists of a combination of a dimension reduction of multi-spectral and a particle filter. In our novel algorithm, a generallized likelihood ratio test (GLRT) method is first applied to the original multi-spectral IR image to reduce dimension and provide the priori of targets. A TBD method based on particle filtering is then applied to the sequence obtained from dimension reduction of raw multi-spectral IR image. Experimental results are presented for the proposed algorithm for detecting and tracking three dim moving targets with varying intensity in multi-spectral IR image sequence of 20 bands and 30 frames. The results show that the proposed algorithm can detect and track multi-targets with a signal-to-noise ratio (SNR) as low as 3dB.

Testability virtual verification technique based on Modelica

By comparing the test verification method, the testability virtual verification technique based on Modelica is proposed. This paper designs the model architecture of testability virtual verification, completes implementations of the testability virtual verification and develops a software about testability virtual verification based on OpenModelica. And through a system instance, practicality and accuracy of the function about testability virtual verification in this subjects are verified.

Fuzzy algorithm for color recognition and realization on FPGA

This paper designs a fuzzy algorithm for color recognition. We use probability and statistics method to derive membership function so as to eliminate effects of brightness on RGB values. This algorithm is implemented on FPGA, which uses IP cores and gives full play to the FPGA high data processing speed and low power consumption. Therefore it has a promising outlook in industrial production.

Comparative researches on scattering properties of random surface

The different parameter characteristics of two types of surfaces with Gaussian distribution and fractal characteristics are discussed, and the outline of two different surface models are given in this paper. By the KA, Gaussian rough surface scattering coefficient is deduced, and the strength of electromagnetic scattering from fractal surfaces is calculated. Two scattering characteristic curves of different rough surface simulation models are compared. The simulation results show, for the Gaussian rough surface, the scattering characteristic is close to the specular scattering properties when the rms height δ is small enough and correlation length l is large enough. While, for nearly smooth fractal surfaces, with the increase of the fractal dimension D, the scattering showed a more pronounced angular distribution characteristics.

The fault diagnosis of switching power supply based on the principle of the sensitivity sequence of node-voltage

This paper studies on the method for the fault diagnosis of switching power supply. The method is based on the diagnosis principle of the sensitivity sequence of node-voltage and refers to the fault dictionary method which is mostly applied to the artificial circuit without tolerance and the linear circuits. In this paper, it is extended for the nonlinear circuit of switching power supply with tolerance. The method is applied to the fault diagnosis of switching power supply, and an illustrative example is given which is proposed to validate its feasibility and effectiveness based on the fault simulation platform.

Study on position detection method of multi-stage coilgun projectile

The coilgun has important application prospect in space navigation and national defense, but the position of the projectile is difficult to decide. BRDF (bidirectional reflectance distribution function) perfectly describes the hemispherical spatial reflected characteristics and scattering characteristics of material surfaces. The application of BRDF on measuring projectile position in multi-stage coilgun is studied in this paper. The concept and the measurement theory of BRDF are discussed, and the system equation of multi-stage coilgun is analyzed. The position detection system of multi-stage coilgun projectile is designed based on the BRDF value. Results show that, no matter how many stages the driving coil adopts, only one set of the optical irradiation-receiver unit is needed. The position detection system of multi-stage coilgun becomes very simple and the projectile is easy to be controlled based on the BRDF measurement technique.

Multi-electrode solid electrolyte sensor for monitoring hydrogen and the adaptive identification algorithm of hydrogen concentration

In the background of energy crisis, new energies are paid close attention to. Hydrogen energy has the advantages of little pollution, high energy density, huge abundance and so on, so its more attractive than other new energies. However, due to hydrogens easiness to explode, monitoring is rather necessary during its use and storage. This essay designs a Multi-electrode solid electrolyte hydrogen sensor using Pt as its measuring electrode, W as its reference electrode, Ni as its adjusting electrode and the mixture of phosphotungstic acid and glass powder as its electrolyte. Moreover, it comes up with the fitting based on the adaptive algorithm of back-propagation neuron network to the sensor output, which leads to a precise measurement when using this Multi-electrode solid electrolyte hydrogen sensor for hydrogen density.