  The Galactic black hole candidate H~1743-322 exhibited two X-ray outbursts in
rapid succession: one in August 2010 and the other in April 2011. We analyze
archival data of this object from the PCA instrument on board RXTE (2-25 keV
energy band) to study the evolution of its temporal and spectral
characteristics during both the outbursts, and hence to understand the
behavioral change of the accretion flow dynamics associated with the evolution
of the various X-ray features. We study the evolution of QPO frequencies during
the rising and the declining phases of both the outbursts. We successfully fit
the variation of QPO frequency using the Propagating Oscillatory Shock (POS)
model in each of the outbursts and obtain the accretion flow parameters such as
the instantaneous shock locations, the shock velocity and the shock strength.
Based on the degree of importance of the thermal (disk black body) and the
non-thermal (power-law) components of the spectral fit and properties of the
QPO (if present), the entire profiles of the 2010 and 2011 outbursts are
subdivided into four different spectral states: hard, hard-intermediate,
soft-intermediate and soft. We attempt to explain the nature of the outburst
profile (i.e., hardness-intensity diagram) with two different types of mass
accretion flow.

High Energy Astrophysical Phenomena