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Showing papers by "National University of Defense Technology published in 1992"


Journal ArticleDOI
TL;DR: In this article, the authors calculated total, differential, and momentum transfer cross sections for the vibrationally elastic scattering of electrons from molecules in the range of energy 5 -20 eV.
Abstract: Calculated total, differential, and momentum-transfer cross sections are reported for the vibrationally elastic scattering of electrons from ${\mathrm{H}}_{2}$O and ${\mathrm{NH}}_{3}$ molecules in the range of energy 05--20 eV The total cross sections are approximated by a sum of the rotationally elastic ones and the rotational transition from ground to first excited state (00\ensuremath{\rightarrow}10) The first-order Born approximation with the rotating-molecule model is used in the calculation of the first rotational excitation cross section The experimental value of the dipole moments of ${\mathrm{H}}_{2}$O and ${\mathrm{NH}}_{3}$ are used in this step of the calculation Spherically approximate molecular wave functions are applied to calculate the spherical part of the interactions of the incident electron with the molecule and the rotationally elastic-scattering cross section, in which the static and exchange interactions are calculated exactly within the accuracy of the molecular wave function and a parameter-free correlation-polarization potential is used to account for the polarization effect The agreement of the differential cross sections with the experimental data is good at small angles and reasonably good at intermediate and large angles Good agreement with measured values is obtained for the momentum-transfer cross sections Total cross sections are reported with theoretical results on the e-${\mathrm{NH}}_{3}$ system below 10 eV The possible sources of the discrepancies between the current theoretical and experimental results are analyzed for the total cross sections at very low energies by a quantitative consideration of the contributions of very strong forward scattering at near-zero angles to the total cross sections

19 citations


Proceedings ArticleDOI
18 May 1992
TL;DR: A method of target-position location in a bistatic system is described, and an analysis of the position error is made, and a tracking algorithm is proposed to track a moving target.
Abstract: A method of target-position location in a bistatic system is described, and an analysis of the position error is made. The RMS (root mean square) is used to describe the position accuracy, and constant-accuracy contours are drawn to show the location characteristics of the bistatic system. A tracking algorithm is proposed to track a moving target. A digital simulation has been performed to evaluate its performance. >

3 citations


Journal ArticleDOI
TL;DR: In this paper, the total, differential and momentum transfer cross sections and the spin polarization parameters, S, T and U are presented from 0.04 to 150 eV, and the influences of the loosely bound state in the p-orbital and the low-lying d-wave shape resonance on the spin polarized effect of the scattered electrons are shown to be significant at low collision energies.

2 citations


Proceedings ArticleDOI
18 May 1992
TL;DR: The authors present a general structure for dynamic information processing systems and some principle ideas for dynamic processing techniques are emphasized by two practical applications in the radar signal processing field.
Abstract: The authors present a general structure for dynamic information processing systems. Some principle ideas for dynamic processing techniques are emphasized by two practical applications in the radar signal processing field. The first is radar weak target detection under strong sea clutter, and the second is radar ship target recognition. The corresponding practical detection system and the ship target recognition system based on the proposed dynamic information processing techniques have been developed and tested successfully on low-resolution radars. >

1 citations


Proceedings ArticleDOI
13 Sep 1992
TL;DR: In this article, the normal fire pattern is defined, pointing out the basic condition the fire indexes and the optimal distribution strategies must obey, and the existence of the normal fighting pattern is proved.
Abstract: The fire indexes and the optimal distribution strategies in a tactical game are treated simultaneously. The normal fire pattern is defined, pointing out the basic condition the fire indexes and the optimal distribution strategies must obey. The existence of the normal fighting pattern is proved. The above theories are applied to tactical combat. Notions of fighting strength and shielding strength are proposed, and some tactical conclusions about depth, which would be difficult to obtain without mathematical tools, are presented. >