PLA Navy Submarine Academy
PLA Navy Submarine Academy
Yuan Z.,PLA Navy Submarine Academy |
Xu S.,PLA Navy Submarine Academy
International Conference on Signal Processing Proceedings, ICSP | Year: 2017
Modulation spectrum simulation is important for the simulation of ship radiated noise, because the modulation spectrum contains abundant characteristics of ship target. To satisfy various research requirements for the simulation of ship radiated noise's modulation spectrum, reconstruction method is utilized based on measured ship radiated noise. The generated modulation spectrum is similar to the measured one with good fidelity. The modulation envelopes are simulated by a pulse stochastic process, where pulses are governed by a set of parameters. Among them, the rotation period, blade number, pulse width and modulation depth of the propeller are obtained with demodulation analysis and time domain analysis on the measured signal. The modulation pulses' amplitude parameters can be got by looking up in a correspondence table between modulation pulses' amplitude data and modulation harmonic spectrum lines, which is generated by simulations and data processes. Simulation results show that frequency and power order of the first group of modulation harmonic spectrum lines are well maintained. © 2016 IEEE.
Yu H.,PLA Navy Submarine Academy |
Geng Y.,Hospital of Traditional Chinese |
Zhu H.,PLA Navy Submarine Academy |
Jiang N.,PLA Navy Submarine Academy |
Chen J.,PLA Navy Submarine Academy
CGNCC 2016 - 2016 IEEE Chinese Guidance, Navigation and Control Conference | Year: 2016
Because of its strong autonomy and high reliability, doppler velocity log (DVL) aided inertial navigation system (INS) has been widely used for autonomous underwater vehicle. Focusing on the aspect of long-term INS/DVL integrated navigation, a novel reduced-order Kalman filtering algorithm with primary influencing variables of system errors is proposed, and then observability degree information of the filtering states are obtained from the eigenvalues of the normalized posterior error covariance matrix and used to check effectiveness of the designed filtering model. Experiments are done from collected field test data to demonstrate the advantages and positioning precision of the proposed filtering model. Experimental results shows that, the proposed novel INS/DVL integrated navigation filtering model is effective, and its positioning precision has achieved to be better than 3‰ of the whole voyage within 5 hours under about 4 knots speed. © 2016 IEEE.
Ren S.,National University of Defense Technology |
Chang W.,National University of Defense Technology |
Liu X.,PLA Navy Submarine Academy
Progress In Electromagnetics Research M | Year: 2011
In order to ensure that SAR scene matching aided navigation system can acquire the position errors and yawing errors simultaneously, we propose an image matching algorithm based on Scale Invariant Feature Transform (SIFT). However, the SIFT is proposed for optical image, and its performance degrades when used in SAR image. To enhance the adaptability of SIFT, two ways are employed. One is the application of a preprocessing on image pairs before matching. The other is the establishment of a scale and rotation restriction criteria on tie-points after SIFT matching. Compared with other matching methods, experiment results show that the proposed method is much more suitable for SAR image and successes in matching performance improvement. Furthermore, the method can meet the real-time requirement.
Hu K.,PLA Navy Submarine Academy |
Zhang X.-F.,PLA Navy Submarine Academy |
Liu C.-B.,PLA Navy Submarine Academy
Binggong Xuebao/Acta Armamentarii | Year: 2013
A kind of auto disturbance rejection controller(ADRC) based on genetic algorithm for keeping UUV depth was designed according to the characteristics of UUV maneuvering. Because of more parameters of ADRC, its parameter design was transformed to parameter optimization. The controller parameter of ADRC in a UUV depth control system was optimized by using the genetic algorithm. The depth control of UUV was simulated without disturbing and near the surface. The simulation results show that the ADRC controller has better depth keeping and anti-jamming performances. Compared with the conventional PID controller, the amplitude and the frequency of steering controlled by ADRC controller are reduced much more obviously. The control quality of ADRC is significantly improved.
Wu H.T.,University of Jinan |
Jiang Y.S.,PLA Navy Submarine Academy |
Yue Y.L.,University of Jinan
Ceramics International | Year: 2012
Trirutile-structure MgTa 2O 6 ceramics were prepared by aqueous sol-gel method and microwave dielectric properties were investigated. Highly reactive nanosized MgTa 2O 6 powders were successfully synthesized at 500°C in oxygen atmosphere with particle sizes of 20-40 nm. The evolution of phase formation was detected by DTA-TG and XRD. Sintering characteristic and microwave dielectric properties of MgTa 2O 6 ceramics were studied at different temperatures ranging from 1100 to 1300°C. With the increase of sintering temperature, density, ε r and Q·f values increased and saturated at 1200°C with excellent microwave properties of ε r ∼ 30.1, Q·f ∼ 57,300 GHz and τ f ∼ 29 ppm/°C. The sintering temperature of MgTa 2O 6 ceramics was significantly reduced by aqueous sol-gel process compared to conventional solid-state method. © 2012 Elsevier Ltd and Techna Group S.r.l. All rights reserved.
Bin X.,PLA Navy Submarine Academy |
Chunsheng S.,PLA Navy Submarine Academy
Proceedings - 2011 International Conference on Virtual Reality and Visualization, ICVRV 2011 | Year: 2011
A SERIES MODELS FOR RADAR DETECTION RANGE UNDER COMPLEX ELECTROMAGNETIC ENVIRONMENT WERE ESTABLISHED, INCLUDING ANTENNA GAIN, PROPAGATION IN MULTI-PATH, ATTENUATION, CLUTTERS OF RAINFALL AND SEA SURFACE, AND ACTIVE ELECTRICAL JAMMING. RADAR RANGE SIMULATION WITH VISUALIZATION IS IMPLEMENTED AND PROVIDES DIRECT IMAGE FOR TACTICAL DECISION. © 2011 IEEE.
Wang X.,Shanghai JiaoTong University |
Wang X.,PLA Navy Submarine Academy
Journal of Software | Year: 2013
Due to having the explicit evidential reasoning (ER) aggregation function, the analytical ER algorithm has been extensively applied to decision problems under uncertainty. However, there are some different opinions to the validity of the analytical ER algorithm. In this paper, a new method is proposed for proving the equivalence between the recursive and analytical ER algorithms, in such a way that is different from and, it is believed, mo e rigorous than that of Wang et al (2006). The new method is based directly on Dempster-Shafer's combination rule and mathematics induction principle. It allows to consider simultaneously the combination and normalization of evidence. In addition, the iterative relationship of the normalization factors between two algorithms is derived. The paper further demonstrates the validity of the analytical ER algorithm theoretically and clarifies the relationship between the recursive and analytical ER algorithms. Index Terms-Dempster-Shafer theory; combination and normalization of evidence; multiple attribute decision analysis; evidential reasoning approach. © 2013 ACADEMY PUBLISHER.
Liu B.J.,PLA Navy Submarine Academy |
Lu W.Z.,PLA Navy Submarine Academy |
Ji H.Y.,PLA Navy Submarine Academy
Applied Mechanics and Materials | Year: 2014
The paper proposed a novel neural network ensemble algrithm (NNNEA) whose individual was generated by clonal selection algorithm. NNNEA can produced individuals of ensemble with better difference than other algrithm. NNNEA was used for predicting ciruit functions and finding sneak circuit. The inputs of NNNEA are states of switches, and the outputs are states of functional components. NNNEA predicted all possible functions of circuit. The sneak circuits can be discovered by comparing the predicted with designed functions. Although there are several limitations of NNNNEA, the results revealed that NNNNEA can exactly discover sneak circuits. © (2014) Trans Tech Publications, Switzerland.
Xing S.-L.,PLA Navy Submarine Academy |
Huang X.-K.,PLA Navy Submarine Academy
Applied Mechanics and Materials | Year: 2014
A kind of tapered and spherical combined liner shaped charge warhead is researched, and the damage mechanism is analyzed. The physics modle of warhead to columniform hull target is build, numerical simulation is done. The result shows that the shaped charge jet formed by this structure can provide movement space, which is in favor of damaging target with water layer. © (2014) Trans Tech Publications, Switzerland.
Jiang N.,National University of Defense Technology |
Li Z.,PLA Navy Submarine Academy |
Yang H.,National University of Defense Technology |
Hu Y.,National University of Defense Technology
Guangxue Xuebao/Acta Optica Sinica | Year: 2012
The principle of polarization maintaining fiber (PMF) is analyzed and a three-dimensional model is established by utilizing the finite element method (FEM). The stress distribution and normalized birefringence are obtained through this model. Three pure-optical beat-length measuring systems are carried out for contrastive research and the advantages and disadvantages are described. Experimental results are in good agreement with the theoretical results. Then one simple and effective method to test the beat-length of high-birefringence photonic crystal fiber (Hi-Bi PCF) is chosen and the results indicate that its beat-length is about 1.2 mm. This research provides an effective theoretical method for the analysis of PMF and a convenient experimental system for the beat-length testing of complex structure PMF and Hi-Bi PCF.