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Zhang L.,Academy of Equipment Command and Technology | Sun H.,Academy of Equipment Command and Technology | Xu J.,Wuhan Ordnance Nco Academy
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2010

The laser atmosphere transmission characteristic affects the use of laser in engineering greatly. This paper designed a laser atmosphere transmission characteristic measurement system based on LabVIEW software, a product of NI. The system acquires laser spacial distribution by means of controlling NI image acquisition card and CCD through PCI, controls oscillograph to acquire laser time domain distribution through Ethernet and controls power meter to acquire energy of laser through RS-232. It processes the data acquired and analyses the laser atmosphere transmission characteristic using Matlab, which is powerful in data processing, through software interface. It provided a new way to study the laser atmosphere transmission characteristic. © 2010 SPIE.


Shen J.,Naval Academy of Armament | Shi J.,Naval Academy of Armament | Xiong L.,Wuhan Ordnance Nco Academy
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2016

Underwater terrain aided positioning technology is an effective method to improve the navigation accuracy of underwater vehicle. The route pre-planning on digit map can reduce matching time and improve matching accuracy for underwater terrain aided positioning. In this paper, a kind of route planning method for underwater terrain aided positioning based on gray wolf Optimization (GWO) algorithm is proposed. Firstly, the GWO algorithm was introduced. The objective functions and route planning method was researched combining with terrain matching problem. Secondly, the calculation formulas of underwater terrain entropy were introduced as well as the terrain information distribution. Thirdly, simulation parameters were set and the best planning route was get using GWO route planning method. Finally, the terrain matching simulation of ICCP was implemented along with the planned route which proved the feasibility of the planning method. © Springer International Publishing AG 2016.


Jian S.,Naval Academy of Armament | Jing S.,Naval Academy of Armament | Lu X.,Wuhan Ordnance Nco Academy
Communications in Computer and Information Science | Year: 2016

In order to make an improved algorithm of good environmental adaptability and practicability, the simulation of three terrain matching algorithms were done on the condition of typical underwater navigation. Firstly, the differences of terrain aided navigation between on land and underwater were researched. Secondly, the underwater terrain aided navigation models were established as well as the underwater terrain aided navigation simulation of TERCOM, SITAN and ICCP. Finally, the influence of INS errors, measurement accuracy, and digital map resolution to algorithms performance were studied. © Springer Science+Business Media Singapore 2016.


Yu H.,Wuhan Ordnance Nco Academy | Zhao D.,Shijiazhuang Mechanical Engineering College
Proceedings - 2011 7th International Conference on Natural Computation, ICNC 2011 | Year: 2011

For multi-LEO combined orbit determination (COD) satellite-network based on space-based tracking telemetry and command (STTC) satellites, kinematic orbit information can be obtained only using the method of precise point positioning (PPP) based on observation models, but the orbits results are not very precise because of the precision of observation data and the Geometry Dilution of Precision (GDOP) of STTC constellation. If kinematic orbit information of low earth orbit (LEO) satellite-network can be taken full advantage of participating in dynamic precise orbit determination (POD) and making them achieve best matching, namely integrative COD models based on kinematic and dynamic information are brought forward in this paper to realize dynamic smoothness of kinematic orbit information, which hopefully can be gained more perfect COD precision of LEO satellite-network. Firstly, single LEO kinematic method based on difference positioning model and the corresponding algorithm was designed, and integrative COD models of COD satellite-network were constituted based on kinematic orbit information of PPP method and dynamic trajectory information. Then integrative COD fusion models based on prior trajectory information were established, and the optimal weighting algorithm of multi-structural nonlinear COD models based on extended prior information was designed. Theoretical analysis and simulation computation results show that COD weighting method based on prior trajectory information can realize LEOs dynamic information optimal matching with kinematic prior information, and can restrain nonlinear influence factor including measure models errors and ephemeris errors to the effects of POD precision by considering models errors modeling and dynamic models sparse parameters denotation, which further ameliorate COD precision of STTC satellite constellation and LEOs. © 2011 IEEE.


Zhao D.,Shijiazhuang Mechanical Engineering College | Yu H.,Wuhan Ordnance Nco Academy
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2011

For multi-LEO combined orbit determination (COD) satellite-network based on space-based tracking telemetry and command (STTC) satellites, kinematic orbit information can be obtained only using the method of precise point positioning (PPP) based on observation models, but the orbits results are not very precise because that the precision of observation data and the Geometry Dilution of Precision (GDOP) of STTC constellation cannot meet the demands of high precision application requirements of LEOs. The high precision denotation model of satellite orbit dynamics based on physics parameter model and mathematics model which associates sparse parameter representation with time sequence analysis, nonlinear semi-parametric combined observation model based on system error parameters modeling and non-parametric component denotation of model error, and COD parameterized fusion model are established aiming at multi-satellite high precision COD based on bi-satellite positioning system and low earth orbiters (LEOs). Then parameters estimation algorithms of the former two kinds of models and the combined estimation algorithm of parameterized fusion model are designed. Theoretic analysis and simulated computation results show that the high precision denotation method of sparse parameters model and the optimized modeling method of observation model considering model error can improve modeling precision, and combined estimation algorithm of parameterized fusion model can synchronously ameliorate orbit determination precision ulteriorly. © 2011 Springer-Verlag.


Xi X.,National University of Defense Technology | Wu Y.,National University of Defense Technology | Wu X.,National University of Defense Technology | Tao Y.,National University of Defense Technology | Tao Y.,Wuhan Ordnance Nco Academy
Sensors and Actuators, A: Physical | Year: 2013

Trimming of resonators is an important process to improve the performance of the cupped gyroscopes. However, it may cause uneven thermal stress which destroys the stability of frequency split and mode shape. Though frequency splits can be reduced to the same degree by trimming at different positions of the resonator, the thermal stresses caused by varying temperatures are significantly different. In this paper, the stress effects of trimmed cupped resonators considering the influence of temperature are studied. The dynamical behavior of the cupped resonators at various temperatures is presented. The stress effects of trimmed resonators due to temperature variation are analyzed based on FE model. Simulation results show that under the same conditions, the bottom trimming gives rise to much more thermal stress than suspension trimming and ring trimming. In addition, a trimming method based on adding mass is studied. Finally, experiments were set up to validate the stress effect by using vibration measurement equipments and frequency analysis equipments. Experimental results show that with reference to the temperature variation the bottom trimming affects the frequency split and the mode deflection of the cupped resonator significantly. © 2012 Elsevier B.V.


Wu Y.,National University of Defense Technology | Xi X.,National University of Defense Technology | Tao Y.,National University of Defense Technology | Tao Y.,Wuhan Ordnance Nco Academy | Wu X.,National University of Defense Technology
Sensors | Year: 2011

The zero bias stability, which is an important performance parameter for vibratory cylinder gyroscopes, is high sensitive to temperature change. It is considered that the varying temperature makes the vibration mode axes unstable, which has significant influence on the zero bias stability. This paper will investigate this problem in detail. First, the relationships between the angular positions of vibration mode axes and the zero bias are analyzed. Secondly, the thermal-modal model of the cylinder resonator with several defects such as mass imbalance, frequency split (FS), and geometry errors are developed by ANSYS. Simulation results show that with the increase of temperature, angular positions of the vibration mode axes obviously change, which leads to a dramatic zero bias drift. Finally, several major influence factors on the angular position stability of vibration mode axes, including frequency split, geometry errors, thermal elastic modulus coefficient (TEMC) and thermal expansion coefficient (TEC) are analyzed in detail. Simulation results in this paper will be helpful for deep understanding of the drift principle of zero bias induced by temperature for vibratory cylinder gyroscopes and also be helpful for further temperature compensation or control. © 2011 by the authors; licensee MDPI, Basel, Switzerland.


Zhao D.,Ordnance Engineering College | Yu H.,Wuhan Ordnance Nco Academy
Proceedings - 2010 IEEE International Conference on Intelligent Computing and Intelligent Systems, ICIS 2010 | Year: 2010

For multi-LEO orbit determination based on Bisatellite Positioning System (BPS), trajectory error of positioning satellites becomes bottle-neck which improves orbit determination precision of LEOs, so we can take combined orbit determination strategy of BPS and user satellites (LEOs) to ameliorate precision. This paper constructs a basic method of range sum observation data simulation for single Low Earth Orbit (LEO) precise orbit determination by statistical analysis of ranging error characteristic, and establishes precise orbit determination model and ranging system error parameters estimation algorithm based on numerical fusion method. Then the paper constructs multi-LEO COD model and corresponding optimal estimation algorithm by introducing weighting factor, and carries out simulation experiments. Simulation computations show that we can improve LEOs COD precision to the greatest extent by constructing rational COD model and optimal weighting algorithm, which proves the feasibility of multi-LEO data fusion model of COD strategy in the paper and can satisfy LEO high precision application requirements. ©2010 IEEE.


Guohui W.,Wuhan Ordnance Nco Academy | Le H.,Wuhan Ordnance Nco Academy | Huidong L.,Wuhan Ordnance Nco Academy | Long H.,Wuhan Ordnance Nco Academy
Proceedings of 2015 IEEE Advanced Information Technology, Electronic and Automation Control Conference, IAEAC 2015 | Year: 2015

With the development of Internet and cloud computing, a data center has an urgent need to use the transformation and optimization of energy. Efficiency evaluation of the data center is imperative. Study on PUE evaluation index. The calculation method of PUE was analyzed. Based on the Web service, efficiency evaluation platform was constructed by ASP and SQL Server database architecture. A dynamic Webpage was refreshed without updating data by using AJAX technology. Man-machine interface was a browser that supported HTML5. Sensors deployment reported monitoring information through Internet gateway. These information was processed automatically in real-time by the platform. The administrator could use the browser to login in any terminal to examine evaluation results and give orders to the actuators. © 2015 IEEE.


Liu X.-P.,Ordnance Engineering College | Zheng H.-Q.,Ordnance Engineering College | Zhu T.-Y.,Wuhan Ordnance Nco Academy
Zhendong yu Chongji/Journal of Vibration and Shock | Year: 2011

Feature selection can eliminate redundant features in an original feature set, find an optimal subset of features and enhance classification accuracy and efficiency in machine fault diagnosis. A feature selection method based on evolutionary Monte Carlo was proposed. Support vector machine (SVM) was taken as a fault classifier, the evaluation criterion was the Wrapper model, and the evolutionary Monte Carlo was implemented for optimal feature subset selection. This method was used in feature selection of a rolling bearing fault diagnosis based on vibration signal. Experimental results indicated the proposed method is effective for feature selection in fault diagnosis.

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