Artillery Academy

Hefei, China

Artillery Academy

Hefei, China
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Lv T.,Artillery Academy | Yan P.,Anhui Agricultural University
International Arab Journal of Information Technology | Year: 2013

XML has become one of the de facto standards of data exchange and representation in many applications. An XML document is usually too complex and large to understand and use for a human being. A summarized XML document of the original document is useful in such cases. Three standards are given to evaluate the final summarized XML document: document size, information content, and information importance. A framework of summarizing an XML document based both on the document itself and the schema is given, which applies schema to summarize XML documents because there are many important semantic and structural information implied by the schema. In our framework, redundant data are first removed by abnormal functional dependencies and schema structure. Then tags and values of the XML document are summarized based on the document itself and schema. Our framework is a semi-automatic approach which can help users to summarize an XML document in the sense that some parameters must be specified by the users. Experiments show that the framework can make the summarized XML document has a good balance of document size, information content, and information importance comparing with the original one.


Lv T.,Artillery Academy | Yan P.,Anhui Agricultural University
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2010

In this paper, the exponential synchronization of delayed fuzzy Cohen-Grossberg neural networks is discussed. Some sufficient conditions are given to ensure the exponential synchronization of the drive-response delayed fuzzy cellular neural networks. © 2010 Springer-Verlag.


Kong X.-K.,Zhenjiang Watercraft College | Kong X.-K.,Nanjing University of Aeronautics and Astronautics | Liu S.-B.,Nanjing University of Aeronautics and Astronautics | Liu S.-B.,Nanjing Southeast University | And 3 more authors.
Optics Communications | Year: 2011

The electromagnetic properties of one-dimensional plasma photonic crystals influenced by random perturbation of structure parameters are studied through transfer matrix method in the paper. The random perturbation of thicknesses of layers as well as plasma frequency of layers can influence the electromagnetic properties of one-dimensional plasma photonic crystal. The random perturbation of thicknesses of layers tremendously impacts the band structure of one-dimensional plasma photonic crystals in high frequency domain. The random perturbation of plasma frequency, however, contributes to the moving of a cutoff frequency in the low frequency domain. The position of the defect mode of one-dimensional plasma photonic crystal randomly moves due to the random perturbations. The effect of random perturbation of plasma frequency is more significant than that of random perturbation of thickness of layers, which alters not only the transmittance but also the position of the defect mode. An improved quality factor and a shortened moving distance of the defect mode are both acquired by increasing the period number. And then this work may provide a crude but useful instrument in analyzing disordered 1DPPCs. Crown Copyright © 2011 Published by Elsevier B.V. All rights reserved.


Liu N.,Artillery Academy | Chai J.-H.,Artillery Academy
Hongwai yu Jiguang Gongcheng/Infrared and Laser Engineering | Year: 2010

For the purpose of eliminating the influence of jamming spots on laser seeker with four-quadrant detector, the characteristics of dual spots detection using classical algorithm of four-quadrant photoelectric detector (QPD) were analyzed. The analysis shows that the jamming spot causes sudden change of the energy received by detector, the energy center of dual spots offsets the energy center of target spot without jamming spot, and the offset value δd is determined by distance d from target spot center to jamming spot center and the energy ratio k of jamming spot to target spot. Based on these, a new algorithm of dual spots detection of four-quadrant laser guidance was put forward. In the new algorithm, the time of jamming spot appearing was determined by the suddenly changed energy, δd was obtained by calculating d and k corresponding to each wave gate, and dual spots error signal was modified by ± δd. The position error signal of dual spots was numerically simulated to test the new algorithm. The simulation results show that the jamming spot can be distinguished from the target spot by the new algorithm and the influence of jamming spot can be eliminated.


Lin L.,National University of Defense Technology | Xu H.,National University of Defense Technology | Xu D.,National University of Defense Technology | An W.,National University of Defense Technology | Xie K.,Artillery Academy
Journal of Systems Engineering and Electronics | Year: 2011

The midcourse ballistic closely spaced objects (CSO) create blur pixel-cluster on the space-based infrared focal plane, making the super-resolution of CSO quite necessary. A novel algorithm of CSO joint super-resolution and trajectory estimation is presented. The algorithm combines the focal plane CSO dynamics and radiation models, proposes a novel least square objective function from the space and time information, where CSO radiant intensity is excluded and initial dynamics (position and velocity) are chosen as the model parameters. Subsequently, the quantum-behaved particle swarm optimization (QPSO) is adopted to optimize the objective function to estimate model parameters, and then CSO focal plane trajectories and radiant intensities are computed. Meanwhile, the estimated CSO focal plane trajectories from multiple space-based infrared focal planes are associated and filtered to estimate the CSO stereo ballistic trajectories. Finally, the performance (CSO estimation precision of the focal plane coordinates, radiant intensities, and stereo ballistic trajectories, together with the computation load) of the algorithm is tested, and the results show that the algorithm is effective and feasible.


Zhang H.-F.,Nanjing University of Aeronautics and Astronautics | Zhang H.-F.,Artillery Academy | Liu S.-B.,Nanjing University of Aeronautics and Astronautics | Kong X.-K.,Nanjing University of Aeronautics and Astronautics | Kong X.-K.,Zhenjiang Watercraft College
Wuli Xuebao/Acta Physica Sinica | Year: 2011

The piecewise linear current density recursive convolution (PLCDRC) on finite-difference time-domain (FDTD) method is applied to study the properties of prohibited band gaps for TM wave propagation in the two-dimensional unmagnetized plasma photonic crystal. In frequency-domain, the transmission coefficient of electromagnetic differential Gaussian pulses are computed and we analyzed the effect on properties of tunable prohibited band gaps for the two-dimensional unmagnetized plasma photonic crystals by its relative permittivity of column, lattic constant, dielectric column radius, periodic constant and parameters of plasma. The results showed that the prohibited band gaps can not be broadened by inceasing periodic constant and plasma collision frequency, but can be broadened by increasing relative permittivity of column and plasma frequency. The prohibited gaps also can be widened by decreasing the lattic constant and dielectric column radius for fill rate of a certain value. © Chinese Physical Society.


Li C.-Z.,Nanjing University of Aeronautics and Astronautics | Liu S.-B.,Nanjing University of Aeronautics and Astronautics | Liu S.-B.,Nanjing Southeast University | Kong X.-K.,Nanjing University of Aeronautics and Astronautics | And 5 more authors.
IEEE Transactions on Plasma Science | Year: 2011

The transmission properties of one-dimensional photonic crystals (PCs) consisting of plasma and lossless dielectric have been systematically studied through the transfer matrix method. In this structure, plasma is used as a kind of single-negative (permittivity-negative) material. Because of the coupling between evanescent waves in plasma layers and propagation waves in dielectric layers, comb-like resonant peaks in transmission band are formed without adding any defect layer in plasma PCs. The numbers and positions of peaks can be modulated by the number of the periods, the plasma frequency, the thickness of plasma layers, plasma collision frequency, and the incident angle. © 2011 IEEE.


He W.,University of Wisconsin - Stevens Point | Lv T.,Artillery Academy
4th International Conference on the Applications of Digital Information and Web Technologies, ICADIWT 2011 | Year: 2011

There is an increasing interest in recent years for querying and ranking XML documents. In this paper, we present a new framework for querying and ranking schema-less XML documents based on concise summaries of their structural and textual content. We introduce a novel data synopsis structure to summarize the textual content of an XML document for efficient indexing. More importantly, we extend the traditional vector space model to effectively rank XML documents over the proposed data synopses. We conduct extensive experiments over XML benchmark data to demonstrate the advantages of the indexing scheme and the effectiveness of our ranking scheme. We also compare our framework with Lucene to demonstrate our extended TF*IDF scoring function is effective © 2011 IEEE.


Wu L.,University of Science and Technology Beijing | Wu L.,Shandong University of Science and Technology | Jiang Z.,University of Science and Technology Beijing | Cheng W.,Shandong University of Science and Technology | And 3 more authors.
Mining Science and Technology | Year: 2011

From the year of 1949 to the present, the China national coal output has been increasing quickly and became first in the world in 2009. But at the same time, major coal mining accidents still exist nowadays. In order to review the overall situation and provide information on major accidents of coal mines in China, we investigated 26 major coal mining accidents in China between the years of 1949 and 2009 through statistical methods, each of which led to more than 100 fatalities. Statistical characteristics about accident-related factors such as time, death toll, accident reasons, characters and nature of enterprise were analyzed. And some special conclusions have been achieved. For example, although we have made great progress, the safety situation in China coal mining industry is still serious, and the reasons for the mining accidents are all human errors which are not inevitable. Such results may be helpful to prevent major accidents in coal mines. Moreso, based on both the knowledge of other countries which have good safety situation nowadays and the safety management situation of China, we made suggestion on safety management of China coal mining. In conclusion, countermeasures were proposed in accordance with the results of statistical studies and the analyses of problems existed in coal mines, including the perfection of safety supervision organization, the establishment of cooperating agency among government, coal mines and workers, the perfection of safety rules and regulations, the improvement of safety investment, the enhancement of safety training, the development of safety technique, and the development of emergency rescue technique and equipment. © 2011 Published by Elsevier B.V. on behalf of China University of Mining & Technology.


Tao Z.,Artillery Academy | Tao Z.,Chinese Academy of Sciences | Wu D.,Chinese Academy of Sciences | Liu D.,Chinese Academy of Sciences | And 3 more authors.
Zhongguo Jiguang/Chinese Journal of Lasers | Year: 2011

Lidar is a powerful tool for atmospheric detection, and its estimation of error is an important content for data processing. In the inversion formula of aerosol backscatter coefficient, it is difficult to calculate the partial derivative of aerosol backscatter coefficient for direct measuring variables, and the conventional error transfer formula can not be applied. To solve the above problem, a direct error formula is proposed, and its reasonability and reliability are tested by comparison calculation. This method can be applied in estimation of aerosol backscatter coefficient total error from molecular extinction coefficient error, aerosol backscatter coefficient error at reference point, lidar ratio error and measuring signal error in lidar data processing.

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