The purpose of this study was to develop a period analysis algorithm for detecting new variable stars in the time-series data observed by charge coupled device (CCD). We used the data from a variable star monitoring program of the CBNUO. The R filter data of some magnetic cataclysmic variables observed for more than 20 days were chosen to achieve good statistical results. World Coordinate System (WCS) Tools was used to correct the rotation of the observed images and assign the same IDs to the stars included in the analyzed areas. The developed algorithm was applied to the data of DO Dra, TT Ari, RXSJ1803, and MU Cam. In these fields, we found 13 variable stars, five of which were new variable stars not previously reported. Our period analysis algorithm were tested in the case of observation data mixed with various fields of view because the observations were carried with 2K CCD as well as 4K CCD at the CBNUO. Our results show that variable stars can be detected using our algorithm even with observational data for which the field of view has changed. Our algorithm is useful to detect new variable stars and analyze them based on existing time-series data. The developed algorithm can play an important role as a recycling technique for used data

1. INTRODUCTION
2. OBSERVATIONAL DATA
    2.1 Instruments
    2.2 Selecting the Sky to Apply the Algorithm for Searchingfor Variable Stars
3. DATA ANALYSIS AND THE ALGORITHM FORSEARCHING FOR VARIABLE STARS
    3.1 Data Reduction
    3.2 WCS Information
    3.3 Light Curves and Their Periods
4. RESULTS AND CONCLUSIONS
REFERENCES

• Dong-Heun Kim(Chungbuk National University Observatory/Korea Astronomy and Space Science Institute)
• Yonggi Kim(Chungbuk National University Observatory/Department of Astronomy and Space Science, Chungbuk National University) Corresponding Author
• Joh-Na Yoon(Chungbuk National University Observatory/Department of Astronomy and Space Science, Chungbuk National University)
• Hong-Seo Im(Korea Astronomy and Space Science Institute)