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The grating lobe reduction methods for non-equidistant array antennas in X-Band are proposed in this paper. The following methods are investigated: an active element pattern control, irregular arrangement of subarrays. A horn antenna element is designed to obtain a perfect active element pattern of an array, and a ring-grid aperiodic array composed of trapezoid subarrays with 1664 elements that are irregular arranged is designed. It is worth mentioning that the combination of these two methods can suppress the grating lobes dramatically in limited-scan phased array. In addition, it is more grating lobes reduction using the combination of these two methods compared with other methods for suppressing grating lobes.

S-value and the single-event specific energy distribution for electrons are important quantities of the microdosimetry for understanding biological effects of ionizing radiation, both of which have close relation to other quantities of the microdosimetry. In this paper, these quantities of electrons were calculated by different codes from cell surface to nucleus or the whole cell. The properties of the low-energy electrons, such as δ particle equilibrium and the energy-loss straggling, were applied to Monte Carlo simulation codes including MOCA15, TRAX and Geant4, and these codes tracked the electrons until their energy was lower than our cutoff energy. The results of S-value and the single-event specific energy distribution in cell were compared to the results of the Penelope and MIRD.

This paper offer a method to obtain UAV's flight parameters at auto-landing period based on the algorithm of camera calibration. According to the geometry features of landing ground to obtain vanishing point, the focal length function is established from the u and v axis scale of the image plane, then the attitude and position of UAV are achieved from the calibration result. Simulation indicates that the proposed vision-based method works properly for the UAV autonomous landing.

Based on the purpose of eliminating the background noise from the large structure vibration response signals which generated by hammer excitation, through analyzing the reason of background noise and the features of vibration signals, a noise eliminating method based on Prony algorithm is presented. Firstly, using the summation of a set of cosine attenuation signals to fit the original signal, compute the parameters of cosine attenuation signals, then identified the background noise and constructed its expression, and eliminated it at last. In this paper, through the processing of the simulation signals and practical signals by using the traditional Prony algorithm and improved Prony algorithm separately, the effectivity of the two algorithms are verified. And the comparison results of the two algorithms shows that the improved Prony algorithm is more effective.

When we use the acoustic signal to diagnose gearbox faults, it will be affected by the nonlinear factors and other noise, and thus reduce the accuracy of diagnosis. ICA is a kind of signal processing method based on high order statistic, it can recover the source signals from the linearly mixed signals, but there are disadvantages in processing non-linearity signals, and the Kernel ICA, which is based on nonlinear function space, can solve this problem effectively. Compared to current ICA algorithms, the Kernel ICA is notable for its flexibility and robustness. The paper presented the principle and algorithm steps of Kernel ICA, through the analysis of transient acoustic signal on gearbox combined with order cepstrum analysis, we found the fault characters, and distinguished the gear wearing fault of gearbox successfully, thus showed its feasibility and validity.

The traditional vibration measurement can't do the non-contact, non-decomposed test, and the self-propelled gun can't get the stationary signal, so the traditional FFT can't be used in this situation, in this article, we proposed the order cepstrum analysis and combined transient acoustic signal for gearbox wear fault diagnosis, compared with vibration signals, the experiment showed its effective and superiority.

The aviation gas turbine engine is the "heart" of each kind of modern military airplane, and it is the main power source of military airplane in our army. So the condition detection of aero-engine is an important measure to guarantee the engine's safe working. This paper introduced the principle of order tracking analysis and compared it with the traditional spectrum analysis, expounded the superiority of order tracking analysis. Applied this method to the condition detection of turbine, and certified its validity through experiment.

To illustrate the typical fault test and simulation technologies for artillery, three key aspects are discussed in detail, which are selections of characteristic parameters, dynamic fuzzy inference and virtual prototype. To denote and analyze the typical faults, an index system is proposed from mission reliability angle. Aiming to the deficiencies of traditional fuzzy evaluation method, a new dynamic fuzzy inference method is put forward and adopted into fault forecast fields. To simulate the typical fault emergence and development process, virtual prototype of large-caliber artillery is established and four groups of fault relationships are given as simulation results. Based on the fault test and simulation system, severe faults will be predicted and commander can determine corresponding campaign decision and maintenance decision.

Artillery recuperator is the important part of recoil system. Pressuring sensing technology and micro-electronics technology been adopted, mixed with automatic computation technology for data collection, a general static tester of the gas pressure and liquid quantity of recuperator is used to replace the traditional testing method of gas pressure and liquid quantity of artillery recuperator. Experiments and engineering application prove that the tester is reliable, higher practicability and testing precision, and it can greatly lower the labor intensity of artillery operators, it is an absolutely necessary testing equipment for increasing the artillery technical support capability and battle capability of troops.

Quality evaluation and fault forecast are the key technologies to improve the mission reliability of complicated equipments. Virtual prototyping is first adopted into quality evaluation and fault simulation fields. A type of self-propelled gun is taken as example and its virtual prototyping is established in ADAMS environment. A simulation example is illustrated to show the influencing rules of different fault factors on system performance. To describe the complex dynamic process, fuzzy inference is adopted to evaluate the whole performances of equipments and forecast the possible faults. Finally, the flow chart of quality evaluation and fault forecast is given. Based on the evaluation results, commander can determine whether the equipments are capable for the training or battle missions or not.

Adaptive control system in dealing with the controlled plant with some unmodeled dynamics has his bad performance and deficiencies. To overcome this proposing a the adaptive control system with a model-free external loop as a compensator has been proposed. It consists of two feedback loops, one is the traditional adaptive feedback loop, called inner loop. The other is called model-free adaptive control (MFAC) based external loop, which is used to serve as a compensator for system tracking error caused by time-varying parameters and model mismatch and unmodeled dynamics. The method has very simple configuration. This paper have developed the method, added an control function combination, so that the method has improved the control precision. Simulation results have demonstrated the efficiency of the developed method.

Gait recognition refers to automatic identification of an individual based on his/her style of walking; it is a new biometrics recognition technology. This paper attempts to describe a gait contour by using Fourier descriptors, to make a periodical analysis on the height and width ratio of the gait image, and to solve the problems resulting from an image sequence of different gait cycles by using dynamic time warping. By utilizing the presented algorithm, experiments made on the CMU data bank have achieved a comparatively high correct identification ratio.