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The extremely low temperature in Antarctic inland area has taken a new challenge for telescope design and develop, the adaptability of components and parts in telescope for the environment close to space. The application of high accuracy encoder is the only way to improve the accuracy of tracking, however, due to the temperature requirement, there is no application of encoder under such a low temperature ever since. To realize the high accuracy of tracking and steering in telescope, high accuracy encoders must be applied in it. Based on the analysis of influence on encoder caused by temperature, an initial thermal control measure is carried out. Secondly, the thermal control measure is optimized with the method that consists of CFD simulations and experiments. Finally, an effective thermal control measure is applied on the second telescope of the 3 Antarctic Schmidt Telescopes (AST3). By the comparison of normal temperature experiment and low temperature experiment, the encoder can reach a temperature of about 25 degrees when it is under the circumstance of-80 degrees after the thermal control works, and the power consumes by the thermal control is less than 6W. The experiment result indicates that the thermal control measure can fit the requirement of temperature that ranges from-10 degrees to 80 degrees and the lowly consuming power requirement, the encoder can reliably work in low temperature with the thermal control measure works.

The Large sky Area Multi-Object Spectroscopic Telescope (LAMOST) General Survey is a spectroscopic survey that will eventually cover approximately half of the celestial sphere and collect 10 million spectra of stars, galaxies and QSOs. Objects both in the pilot survey and the first year general survey are included in the LAMOST First Data Release (DR1). The pilot survey started in October 2011 and ended in June 2012, and the data have been released to the public as the LAMOST Pilot Data Release in August 2012. The general survey started in September 2012, and completed its first year of operation in June 2013. The LAMOST DR1 includes a total of 1202 plates containing 2,955,336 spectra, of which 1,790,879 spectra have observed signal-to-noise S/N >10. All data with S/N>2 are formally released as LAMOST DR1 under the LAMOST data policy. This data release contains a total of 2,204,696 spectra, of which 1,944,329 are stellar spectra, 12,082 are galaxy spectra and 5,017 are quasars. The DR1 includes not only spectra, but also three stellar catalogues with measured parameters: AFGK-type stars with high quality spectra (1,061,918 entries), A-type stars (100,073 entries), and M stars (121,522 entries). This paper introduces the survey design, the observational and instrumental limitations, data reduction and analysis, and some caveats. Description of the FITS structure of spectral files and parameter catalogues is also provided., 39 pages, 13 figures