Abstract:According to the characteristics and reality of aerial tactical training in light of an analytic hierarchy process (AHP), entropy theory and fuzzy matterelement theory, this paper builds a fuzzy matter-element model of security evaluation index system for the aerial tactical training space designing scheme based on AHPentropy, and evaluates 17 indexes of task, equipment, environment and management in the scheme system on the basis of this model. The result indicates that this model is capable of finding the connections, computing the distance degree between evaluation examples and standards, and evaluating multiple examples at the same time. In careful consideration of subjectivity and objectivity in evaluating based on the combination of AHP and entropy, the evaluation is very practical.

Abstract:To solve the problem of airlines failure, an optimization model for traffic redistribution based on the theories of hub airline network and complex network is proposea. In the model, the cost is divided into airline cost and node cost. Taking the smallest in the total cost of traffic redistribution as a target in consideration of the effect from nonhub airport on cost and capacitated constraint, the paper works out a cost function based on congestion. The model is solved by particle swarm optimization (PSO). At last, a simulation is made taking the airline between Hangzhou and Xianyang as an example. The results of the experiment show that the proposed model is good in reliability and in validity. And the operability and practicability can be improved by adjusting these parameters.

Abstract:With the growth of four countering capability of the radar network in electronic warfare，the allocation power of jammer becomes a key to the aircraft penetration. For this reason， a method of power allocation based on threat evaluation of collaborative electronic jamming is given. A kind of the radar network threat assessment model is established，and the basic methods of the model through standardization calculate the radar threat assessment value of each attribute corresponds to get radar threat assessment value standardization matrix. The paper obtains a relative degree through calculation of the distance and an ideal solution，and comprehensive threat level calculated for each member. A reasonable power distribution can be performed through the threat level proportion of the radar network on the premise of limited jamming power. Finally, the simulation shows that the method is feasible. The results show that in selecting appropriate radar network for evaluating parameters，interference power allocation can be achieved by using the method, and has a certain reference value for further research in this field.

Abstract:The most existing MIMO radar waveform optimization designs are a narrowband signal designed according to the need of radar tasks in tracking and detecting without the requirement of imaging tasks. A kind of method about MIMO radar waveform optimization design for multi-target ISAR imaging is proposed in the paper. The prior information like target location, RCS, target velocity as well as bandwidth limitation of imaging task is considered in waveform optimization as important constraints, a waveform optimization model for multitarget Imaging is established and solved by the conjugate gradient method. The designed waveform can achieve the imaging of targets in different directions at the same time.

Abstract:Aimed at the problem of imaging task scheduling of multifunction phased array radar, this paper puts forward an adaptive scheduling algorithm for ISAR imaging radar based on pulse interleaving. Firstly, the paper calculates the required resources for sparse aperture ISAR imaging according to initial cognition of target feature. On the basis of that, a rational and optimized scheduling model of interleaved pulsedwelling is established, and then radar resources can be allocated reasonably under condition of the dual restraints by time and energy. Average interleaving degree is proposed as an indicator of measuring imaging radar resources scheduling. At last, different targets are imaged respectively by using compressed sensingbased sparse aperture ISAR imaging method, and the required imaging resolution is achieved while the resource utilization rate is enhanced apparently. The simulation result shows that this algorithm is feasible.

Abstract:Aimed at the problem that by using the polar format algorithm (PFA) the computation amount is large and its imaging precision is affected by interpolation, a fast polar format imaging method of MIMO radar with sparse array based on two-dimensional CZT is proposed in this paper coupled with compressed sensing (CS) and the Chirp-Z translation (CZT). Instead of the interpolation, the CZT achieves the interpolation-re-sampling process by selecting proper parameters. With the imaging size changing, the simulation results show that the amount rate of computation work by the proposed algorithm to the PFA is maintained between 0.22～0.4, thus reducing the computation amount and improving the precision availably with small image entropy.

Abstract:Aimed at the resource scheduling problem of phased array radar in multiple target tracking, this paper proposes a task scheduling algorithm based on modified priority. The algorithm introduces the threat of the target to radar into the design of the target task priority. Firstly, the target threat degree is defined. A method that combines comprehensive decision-making of information entropy with subjective weighting is used to calculate the target threat degree in accordance with various parameters of the target and radar. And then, the algorithm synthesizes planning of the target threat degree, the priority of function mode of the task and the deadline of the task to obtain the comprehensive priority. Finally, the calculation process of target threat degree and task scheduling are simulated. The simulation results indicate that the calculation results of target threat degree conform to the demand for tracking resource distribution in different target threat degrees of targets, and the algorithm has a certain superiority for executing high threat tasks, compared with the traditional algorithm.

Abstract:Aimed at the problems that the time cost is excessive and very hard to meet the needs of user equity by using the existing dynamic spectrum allocation algorithm, a parallel spectrum allocation algorithm based on user equity is proposed. On the basis of mathematic model of CSGC（Color Sensitive Graph Coloring） dynamic allocation theory, HE（Homo Egualis） social model is introduced to calculate the equity parameter for proposed algorithm, and then the equity of parallel allocation can be modified by using this parameter to ensure the allocation algorithm fairly, and can satisfy the time cost as well. Meanwhile, the influence on algorithm caused by equity parameter design is also discussed. The simulation result show that when number of user is fixed, the fluctuation of user benefit will be smooth and steady, the equity will also be satisfied. With the increasing number of frequency band , the time cost of the algorithm will stay at a low level.

Abstract:Synthetic Aperture Radar（SAR）image edge detection is a hot issue in the field of image processing. It is difficult to eliminate the noise and internal texture of SAR image by traditional methods. By making use of the properties of the receptive field and the surround suppression mechanism to texture and noise in the homogeneous region in cells with nonclassical receptive field in Primary Visual Cortex (V1) in human visual system, this paper proposes a new method of SAR image edge detection by modeling the information processing mechanism of V1 Through the operations of odd and even decomposition, spatial summation and normalization by Gabor filter, the paper simulates the properties of the classical receptive field. A series of computational steps motivated by surround suppression mechanism are added to suppress the texture and noise in homogeneous region and preserve the contour wanted. The simulation results show that the proposed method can suppress most texture in the homogeneous region of the four kinds of SAR images used in the article，can weaken speckle noise to some degree, and edge detection effect is better than that of the canny detector. The method can be applied to the edge detection of SAR images.

Abstract:Traditional eddy current testing technology generate a magnetic field excitation by a cylindrical excitation coil, and collect magnetic field perturbations through the detecting coil, however, the magnetic field generated by excitation coil is much stronger than those generated by defect, so the defect detection sensitivity of the sensor with this structure is not high, and it is necessary to adopt difference methods to obtain the information of defect. A new type of eddy current sensor is proposed, which can be used to change the spatial distribution of the excitation magnetic field by using the rectangular excitation coil, so that the defect can be quantified without difference. Based on the analysis of the principle of the new sensor, the sensitivity difference between the traditional sensor and the defect detection is analyzed by simulation. The sensor size and excitation frequency were optimized, and the quantitative detection ability of the new sensor was verified. Simulation results show that the new sensor has high detection sensitivity and defect quantitative accuracy. To lay the foundation for the research of single excitation and multi detector array eddy current sensor.

Abstract:Three-dimensional features of targets include delicate structure and micro-motion information. Taking coneshaped warhead as an object of study, this paper proposes a three-dimensional reconstruction method of cone targets based on the mixed netted radars consisting of both narrowband and wideband ones. Firstly a procession model of cone-shaped target is established, and the microDoppler modulation characteristic is analyzed for radar echo in different radar systems. Then the paper, by using the improved algorithm and the least-square theory, extracts and estimates the amplitude and phase information of each scattering center. The gray cognate analysis method is used to correlate those corresponding non-ideal scattering centers. Thirdly, the amplitude and phase information fusion equations in different radar systems are set. Based on the equations, procession parameters and configuration parameters of cone target are calculated to identify the position parameters and realize the three-dimensional reconstruction. The simulation results show that the precision of three-dimensional reconstruction is at about 91% when the signal noise ratio (SNR) is under condition of 5dB.

Abstract:Aimed at the problem that the Kernelized Correlation Filter position of the target is in the image through the correlation filter，such generative models are easily subject to the interference from the backgrounds similar to the targets, causing the failure of tracking, this paper strengthens the criterion of correlation filter based on the maximum margin. The similar backgrounds are updated as negative samples to improve the tracking robustness. First, the algorithm constructs a model of maximum margin correlation and distinguishes backgrounds similar to the targets by classifier. Second，the obtained similar backgrounds are taken as negative samples and the tracking model is updated online during the tracking process. So the algorithm can adapt to the various changes of the target movement and can achieve the goal of robust tracking by online updating the target tracking model. The paper selects seventeen typical image sequences of OTB2013 and VOT2014 database and compares the results of the six correlation tracking algorithm in the experiment. The experimental results show that the algorithm can improve by 8% and by 2% on precision and success rate compared with the suboptimal algorithm, the tracking efficiency is the best and the tracking realtimeability is comparatively good.

Abstract:The traditional methods based on regional characteristics of image fusion have two limitations. First, the fusion rule of low-frequency sub-image does not make full use of regional energy information and regional edge information at the same time. Second, the fusion rule of high-frequency sub-image even sometimes ignores the directional information. In order to overcome the limitation for getting more the neighborhood information from the traditional region characteristics method, an improved image fusion method is proposed based on the NSST（Non-Subsampled Shearlet Transform）and the modified directional fusion rule. First, the source images are decomposed by the NSST algorithm to obtain a low-frequency sub-image and a series of high-frequency sub-images. Subsequently, the low-frequency sub-image is performed by adaptive contrast Spatial Frequency algorithm based on region energy, and the high-frequency sub-images contained the directional information is performed by a novel Sum-modified-Laplacian fusion rule. Finally, the method is verified by living example.

Abstract:Aimed at the problem that it is difficult for FRFT-TDCS to get rid of multi-component LFM interference signals by the traditional TDCS threshold design methods, this paper proposes a threshold design method based on noise estimation for FRFT-TDCS. On the basis of analyzing the FRFT domain spectrum distribution characteristics of LFM interference signals and noise, the paper obtains a set of unoccupied spectrum subcarrier through the FRFT domain energy broadening and position of interference signals, and determines the system adaptable threshold according to the amplitude statistical properties of Gaussian white noise and the requirements of system performance. The simulation results show that the proposed method can eliminate the single component LFM interference signal spectrum while λ>2.6, can eliminate the multicomponent LFM interference signal spectrum, and can retain “clean” spectrum while 3<λ<2.2. Compared with the traditional hard threshold setting method, the proposed method can achieve a better effect of interference eliminating and performance of BER under condition of multi-component LFM interference signals .

Abstract:With the rapid development of Internet technology, the size and complexity of the database are continually growing, the traditional classification method can no longer meet the demand of the classification of complex data. For this reason, a data classification algorithm based on variational Bayesian is proposed. This paper introduces the variational approximation theory on the basis of traditional Bayesian inference, combines with the thought of maximum expected algorithm, utilizes the mean field theory in the statistical physics, and simulates taking Gaussian mixture model as an example. The experimental results show that the randomly generated data are composed of the three Gaussian models mixed after 382 iterations, the lower bound of likelihood function rises with the increase of iteration number, the curve becomes flat as expectation after 350 iterations, and the mean value and the inverse of covariance matrix close to the real data are obtained in the range of allowable error. Under the requirement of high precision, the calculation speed is faster, calculation efficiency is higher, and all of these accord with the demands of actual engineering application background.

Abstract:Aimed at the problems that the message formats supported by multiple data links are different, and multiple data links in communicating with each other are difficult to interoperate, a multi-data link system task assignment model based on message processing platform is proposed, on which the message format is transformed and distributed to the corresponding data link. This paper analyzes several dominant metrics in multi-data links interoperability, and gives the mathematical expression. Then considering a typical application of information communication among multi-data links, a simulated annealing particle swarm algorithm is used to solve this model. The simulation result shows that multi-data link system can both meet the count of interoperability indicators and achieve effective information communication under either low load or medium load condition. At the same time, compared with the standard particle swarm optimization algorithm, the improved algorithm significantly improves the convergence speed and the global search ability.

Abstract:The Statistical test and analysis methodologies are applied to Operational Test and Evaluation (OT&E) by analyzing the mechanism of OT&E. The step of Operational Test and analysis (OT&A) based on Statistical test and analysis methodologies are concluded and the related theory of OT&A is discussed. An OT&A case of AirtoAir Missile are studied to verify the proposed method. Both the science and stringency of OT&E are improved by applying statistical test and analysis methodologies.

Abstract:Locally repairable code (LRC) is a class of code aimed at local correction of erasures. This code is applied widely in the distributed storage systems. A code with locality r, requires the access of at most r other codeword symbols to recover a symbol from erasure. This paper studies the existence and construction of binary cyclic LRCs with locality r≤3. Based on the theory of defining set of cyclic codes, the paper describes by adopting the dual of LRCs. After a consideration into the constraints among code parameters, LRCs are constructed and optimized. The existence of binary cyclic codes in arbitrary length with locality 1 is proved and the construction of LRCs meeting the Griesmer bound with locality 1 is offered. Judgment on the existence of binary cyclic codes with locality 2 and 3 is put forward in which LRCs in short length with satisfying parameters and locality 2 and 3 are constructed on the basis of binary cyclic codes in length 7≤n≤99. There is much in these results that researchers further study the relationship among locality and other code parameters as well as the construction of LRCs with satisfying parameters in arbitrary length for reference.