  We present an examination of the multi-wavelength observation of a C7.9 flare
which occurred on 1998 November 10. This is the first time of imaging
observation of the quasi-periodic pulsations (QPPs). Four bursts were observed
with the hard X-ray telescope aboard Yohkoh and the Nobeyama Radioheliograph
during the impulsive phase of the flare. In the second burst, the hard X-ray
and microwave time profiles clearly showed a QPP. We estimated the Alfven
transit time along the flare loop using the images of the soft X-ray telescope
aboard it Yohkoh and the photospheric magnetgrams, and found that the transit
time was almost equal to the period of the QPP. We therefore suggest, based on
a shock acceleration model, that variations of macroscopic magnetic structures,
such as oscillations of coronal loops, affect the efficiency of particle
injection/acceleration.
