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With the application of the unmanned aerial vehicle (UAV) on the battlefield, how to avoid obstacle and reach the goal has been becoming crucial issues. In this paper, a collision avoidance algorithm for UAV based on the conventional proportional navigation (PN) guidance law is studied. First, the concept of the collision avoidance vector is introduced. Based on the idea of proportional navigation...
In this paper, we propose an improved QP-Free method for nonlinear inequality constrained optimization based on linear equations. This new algorithm only needs to solve two systems of linear equations. It has the following advantages: (1) the amount of computation is greatly reduced; (2) the good nature of the descent directions is fully used; (3) the obtained search direction is feasible. Under some...
A novel conical horn antenna loaded with ball cone dielectric is designed in this paper. The design method of the dielectric surface equation is given. The comparison between the smooth wall conical horn antenna and the four types of horn antennas, the dielectric lens-corrected horn antenna, the dielectric loaded horn antenna, the cone dielectric loaded horn antenna, and the ball cone dielectric loaded...
Parallel micro-manipulators adopt flexible joints and the flexible deformation makes the up-platform move. Considering the counter-force/moment of the flexible joints, we concern the statics of a 6-PSS parallel micro-manipulator with perpendicular structures(PMMWPS), the construction of a relationship model between force output of PZT actuators and outer load on the up-platform, and the definition...
A frequency-domain parameter identification method based on improved particle filtering algorithm is proposed to identify parameters of generator excitation system. The process model and measurement model of the nonlinear excitation system parameter identification are proposed, which can correct the position of each particle based on the residual and the error between the particle and the local optimal...
Precise results of eigenvalues can be obtained in order reduction approach for special modes. To improve calculation efficiency, the order reduction approach is analyzed in this paper. In the process of order reduction, every set made up of retained state variables is shared by different modes, which reduces calculation amount. Based on real number expression of complex matrix, the expression of outer...
Mathematical mass transfer model of racemic resolution for chiral compounds using HFSLM was presented in this study. Factors such as transportation resistance of boundary layers in strip phase inside the hollow fiber and in feed phase on the shell side of the hollow fiber module, diffusion resistance in the membrane solution and equilibrium constant of interfacial chemical reactions are considered...
A 1D object is a segment with several known-distance markers, and calibration methods with 1D objects are more flexible than those with 2D/3D objects. Under the pinhole camera model, it is proved that the calibration with free-moving 1D objects is not possible. For a central catadioptric camera setup, can the camera be calibrated by a 1D object under general motions? In this paper, we prove that a...
Due to today's diverse resource constraints and user preferences, video adaptation attracts more and more research interests. A video adaptation framework for scalable video coding(SVC) is proposed in this paper. The content description is acquired off-line, and then a bitstream syntax description is automatic created by a format-specific parser. Finally, video adaptation is implemented based on bitstream...
Based on the theory of fractional order differential equation, a fractional order integral compensator of slide mode control(SMC) with its design method are presented for control of time delay system. The specify memory characteristic of fractional calculus is used to improve the dynamic performance for SMC. A simulation example is given and its results show the new kind of compensator has the effect...
Flame stability is an important issue for combustion-based micro power generation systems. In the present work, we developed a planar micro-combustor with a bluff body fro micro power generation systems. Comparative study on lean and stoichiometric hydrogen/air flames in the micro-combustor with and without a bluff body was performed numerically. The results show that the blowoff limit is extended...
Flame stabilization is of great importance for combustion-based micro power generation devices. In the present work, we developed a planar micro-combustor fitted with a bluff body at the entrance of the combustor chamber. A comparative study on stoichiometric hydrogen/air flames in the planar micro-combustor with and without a bluff body was performed numerically. Computation results demonstrate that...
The positioning precision of multilateration system is relevant with the location of remote stations which is reflected by dilution of precision (DOP). It is a common sense that adding a new station will improve the positioning precision because of the decreasing of DOP. However, nobody has declared the quality relationship between the number of stations and DOP. In this paper, we firstly analyze...
A class of reference signal based (RSB) beamforming algorithms is proposed based on a symmetrically distributed array (SDA) by constraining its weight vector to a specific conjugate symmetric form, which is derived from the beamformer with a minimum mean square error (MSE). The effect of the additional constraint is equivalent to adding a second step in the derived adaptive algorithms. Moreover, since...
In wireless sensor networks (WSNs), Energy consumption will be reduced by grouping all the sensor nodes into clusters and letting the data be aggregated at cluster heads(CHs). In this paper, we address the issue of how many tiers in a given clustering scheme are optimal in saving energy. We present a method to calculate the optimal tier number with consideration to the energy consumption both in data...
This paper presents the sliding exponential window max-correlation matching (SEWMCM) adaptive algorithm and the sliding rectangular window max-correlation matching (SRWMCM) adaptive algorithm for finding the maximum correlation of two different signal vectors. A unified approach to the steady-state excess mean square error (MSE) performance analyses for proposed algorithms is developed, including...
According to the symmetric characteristics of bispectrum, a novel feature extraction scheme, which includes the summation-at-every-column feature vector, the summation-at-every-row feature vector and their combination in a triangle area, one of the 12 symmetric areas of bispectrum, is proposed. By using One-against-One (OAO) method of multi classification of Support Vector Machine (SVM), the mean...
This paper proposes a robust rear-view camera based moving object detection algorithm for backup aid and parking assist applications. A single fish-eye camera is used in order to get much larger FOV (field of view) for object detection. To detect various moving objects such as vehicles and pedestrians, the ego-motion of host vehicle is firstly estimated by A robust NGPP (near ground point projection)...
Zoom tracking plays an important role in camera tracking. It is always a challenge for camera calibration when the focal length becomes long, for the principal plane would move and rotate inevitably in the process of zoom. To deal with this problem, a new method is presented in this paper, in which we does not lay emphasis on the camera calibration itself, but focuses on the compensation to the extrinsic...
Random Walks has less interaction, better accuracy and higher computing independency. We introduce local intensity entropy to modify the weight function in Random Walks, in order to consider not only the intensity change of adjacent pixels, but also the statistical features of regions. Then we put forward a real-time interactive object extraction system for high resolution remote sensing images based...
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