  The Galactic black-hole candidate GX 339-4 exhibited several outbursts at
regular intervals of \sim 2-3 years in the Rossi X-ray Timing Explorer (RXTE)
era. After remaining in an almost quiescent state for 3 years, it again became
X-ray active in 2010 January, continuing to be so over the next \sim 14 months.
We study the timing and spectral properties of the black hole candidate (BHC)
during its recent outburst using RXTE PCA data, starting from 2010 January 12
to 2011 March 6.
  Our study provides a comprehensive understanding of the mass accretion
processes and properties of the accretion disk of the black hole candidate. The
PCA spectra of 2.5-25 keV are mainly fitted with a combination of two
components, namely, a disk black body and a power-law. The entire outburst as
observed by RXTE, is divided into 4 spectral states, namely, hard,
hard-intermediate, soft-intermediate, and soft. Quasi-periodic oscillations
(QPOs) were found in 3 out of the 4 states, namely hard, hard-intermediate, and
soft-intermediate. The QPO frequencies increase monotonically from 0.102 Hz to
5.692 Hz in the rising phase of the outburst, while during the declining phase
QPO frequencies decrease monotonically from 6.420 to 1.149 Hz.
  The recent outburst of GX 339-4 gives us an opportunity to understand the
evolution of the two-component accretion rates starting from the onset to the
end of the outburst phase. We found that the QPO frequency variation could be
explained by the propagating oscillatory shock model (POS) and the hardness
versus intensity variation can be reproduced if we assume that higher viscosity
causes the conversion of a low angular momentum disk component into a Keplerian
component during the outburst phase. The decline phase starts because of the
reduction in the viscosity.
