White dwarfs are the final stage of the stellar evolution. About 80% of all known white dwarfs are of DA type, who have hydrogen-rich atmospheres. When the DA white dwarfs evolve and pass through the instability strip, which is in the effective temperature range of 10850 to 12270 K, they become pulsating white dwarfs. These pulsating DA white dwarfs are known as the DAV or ZZ Ceti stars. By detecting and analysing the oscillation modes in the pulsating white dwarfs, we can get the information about the invisible interiors of the star. The technique is called asteroseismology, somewhat similar to the technique that seismologists use to study the interior of the Earth by probing the earthquake waves. Asteroseismology provides a way to determine the essential parameters of the white dwarfs, such as the total mass, the effective temperature, the hydrogen mass fraction and the helium mass fraction. We perform asteroseismological analysis on the two ZZ Ceti stars KUV 11370+4222 and KUV 03442+0719. Some meaningful results are obtained. KUV 11370+4222 was discovered in 1996, which has not been observed since then. We performed observations for KUV 11370+4222 in 2010 January. From the Fourier transform spectrum of the light curves, 10 independent modes are detected. We searched for the best-fitting model by using the observed periods to match the model periods and get it with the total mass of 0.625 Msun, the effective temperature of 10950 K, and the helium mass fraction and hydrogen mass fraction of 10^{-2.2} and 10^{-4.0}, respectively. We have found a triplet of frequency split by rotation, which are l=1 modes. Using the frequency shifts we estimate a rotation period of 5.56 h. Besides it, another l=1 mode is identified. The other observed periods are identified as l=2 modes. At last we investigated the property of the mode trapping. KUV 03442+0719 was originally discovered in 2005. We performed observations for it in 2010, 2011 and 2012. From the three years' Fourier transform spectra, a total number of 43 pulsation modes are detected. We found out a set of complete quintuplets, five sets of incomplete quintuplets and two sets of incomplete triplets among these modes. They are interpreted as rotational splits of l=2 and l=1 modes. We thus derive a mean rotation period of 6.71 h from the values of splitting spacing. We perform asymptotic analysis to get preliminary identification of the observed pulsation modes.
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