| The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) is the latest configuration of astronomical telescope that was raised by astronomer of China. This project was proposed by a research group headed by Wang Shouguan and Su Dingqiang, members of the Chinese Academy of Sciences (CAS), and was supported widely by astronomical community. A formal proposal for the project submitted by CAS has been listed, after repeated reviews, into "The National Mega-Science Facilities Program" in 1996. The proposal was approved by State Planning Commission (SPC) in April, 1997, and the feasibility study was approved by SPC in August, 1997. Its construction period is 8 years, coming into operation at 2008.From 2006 to 2008, all sub-mirrors and instruments of LAMOST will be installed gradually until fully completion. Before all sub-mirrors and instruments installed, LAMOST team planed a temporary scheme in order to do some testing observations. The plan will start from the beginning of 2007, and the part LAMOST will have 3×3 Mirrors (3 sub Ma and 3 sub Mb) with 1.25 degree field, and 250 fibers on its focal plane at that time. For the mini system, astronomers are planning a set of observations during the engineering process, which includes small amount of stars from 18 to 19 magnitude .As a big-science project, this project aims at the wide field astronomy and astrophysics, and seizes the valuable opportunity to open up the optical spectroscopic observation in large scale, it realizes a breakthrough in combining large aperture with wide field of view in optical telescope by using original concepts and ingenious design. LAMOST is a meridian reflecting Schmidt telescope laid down on the ground with its optical axis fixed in the meridian plane. It consists of a reflecting Schmidt corrector MA at the northern end, a spherical primary mirror MB at the southern end and a focal plane in between. Both the primary mirror and the focal plane are fixed on their ground bases, and the reflecting corrector, as a coelostat, tracks the motion of celestial objects. Celestial objects are observed around their meridian passages. The light collected is reflected from MA to MB, and then reflected by MB and forms image of the observed sky on the focal plane. The light of individual objects is fed into the front ends of optical fibers accurately positioned on the focal plane, and then transferred into the spectrographs fixed in the room underneath, to be dispersed into spectra and recorded on the CCD detectors, respectively and simultaneously. LAMOST is expected to be a unique astronomical instrument in combining a large clear aperture and a wide field of view. Since its 4m aperture enables it to obtain the spectra of faint celestial objects down to 20.5m with 1nm spectral resolution in 1.5 hours exposure, and its 1.75m focal plane corresponding to the 5 ° field of view can accommodate several thousands of optical fibers, which could obtain 4,000 spectra of celestial objects simultaneously, becoming the telescope of the highest spectrum acquiring rate of several ten-thousands of spectra per night. Therefore, it is a challenge to us that how to observe these materials purposefully, in order, no mistakes in a short time. It is an important task to make good use of LAMOST, organize effective observation, improve observational efficiency and shorten observational cycle. And in the observation practicality, there are many irregularity, including the weather and machine trouble etc. In order to avoid waste observational time, we must have the urgent plan for special condition. It is hard to realize an observation project with about 4000 objects manually. That is the reason why we design the Survey Strategy System (SSS) to automatic make the observation project.In this article, we introduce the SSS, which include the science goal, design method, integer structure etc. First of all, we put forward kinds of restrictions which influence the result of object -selection of LAMOST. The object-selection model based on static restrictions is established. The effects of each restriction are analyzed by means of simulation.Secondly, we study the observation policy of SSS. The most important question in Dynamic-Object-Selection of LAMOST is how to find a tile which has the maximum object density in the visible sky area. In this paper, Mean Shift Algorithm is applied to solve the problem. The simulations indicate that this algorithm improve the Observation-Efficiency. At the same time, the speed of Dynamic-Object-Selection calculation enhanced obviously.Based on the theories analysised above, we design and realize the software of SSS. The software-reuse technique, object-oriented technique, component and framework based on Design Pattern methodology are used in the system architecture and implementation. The full utilization of advanced computer technologies including the database, distributed computing, real-time computing has benefited the SSS software development. At last, we discuss the development of SSS. The creative of this article is:1) It's the first time to put forward and classify kinds of restrictions which influence the result of object -selection of LAMOST.2) Mean Shift Algorithm is brought forward to solve the Dynamic-Object-Selection question for the first time, which improve the Observation-Efficiency and enhance the calculation speed obviously.3) Design and realize SSS software architecture base on Software Engineering methodology.
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