According to the work characteristics of semi-active laser-guided weapon system, at first, the optical characteristics of the laser received by seeker were analyzed; and mathematical model of the optical signal power received by seeker was established. Secondly, a hardware-in-the-loop simulation(HILS) system was designed for strapdown seeker. In order to simulate energy and laser spot’s continuous variations, a high-precision continuous dynamic laser energy attenuation system and a digital micromirror device(DMD) spot projection system were designed respectively. In the end, the HILS system was used to evaluate the performances of strapdown seeker and the seeker was tested for response coherence among the four quadrants, field of view(FOV), linear field of view, minimum received optical power, and angle measurement accuracy.

No abstract

A Linux operating system is composed of a large number of software packages. Among packages there exist a variety of complex dependency relations, and their management is the foundation of building and maintaining Linux operating system. And the premise of the management is the dependency relations' extraction. Based on the analysis of several different formats of Linux software packages, a unified format for package metadata, which is mainly dependency management oriented, is defined in this paper. Moreover package metadata extraction methods for different package formats, including the RPM and DEB packages, are given. And the corresponding supporting tool is implemented, which lays the groundwork for Linux package dependency modeling and integrity check.

SUMMARYAs a giant in open source community, OpenOffice.org has become the most popular office suite within Linux community. But OpenOffice.org is relatively slow while loading documents. Research shows that the most time consuming part is importing one page of whole document. If there are many pages in a document, the accumulation of time consumed can be astonishing. Therefore, this paper proposes a solution, which has improved the speed of loading documents through asynchronous importing mechanism: a document is not imported as a whole, but only part of the document is imported at first for display, then mechanism in the background is started to asynchronously import the remaining parts, and insert it into the drawing queue of OpenOffice.org for display. In this way, the problem can be solved and users don't have to wait for a long time. Application start-up time testing tool has been used to test the time consumed in loading different pages of documents before and after optimization of OpenOffice.org, then, we adopt the regression theory to analyse the correlation between the page number of documents and the loading time. In addition, visual modeling of the experimental data are acquired with the aid of matlab. An obvious increase in loading speed can be seen after a comparison of the time consumed to load a document before and after the solution is adopted. And then, using Microsoft Office compared with the optimized OpenOffice.org, their loading speeds are almost same. The results of the experiments show the effectiveness of this solution.

No abstract