We present the results of global three dimensional magneto-hydrodynamic simulations of black hole accretion flows .
We focus on the dependence of numerical results on the gas temperature T _ { out } supplied from the outer region .
General relativistic effects are taken into account using the pseudo-Newtonian potential .
We ignore the radiative cooling of the accreting gas .
The initial state is a torus whose density maximum is at 35 r _ { s } or 50 r _ { s } from the gravitating center , where r _ { s } is the Schwarzschild radius .
The torus is initially threaded by a weak azimuthal magnetic field .
We found that mass accretion rate and the mass outflow rate strongly depend on the temperature of the initial torus .
The ratio of the average Maxwell stress generated by the magneto-rotational instability ( MRI ) to gas pressure , \alpha \equiv \langle B _ { \varpi } B _ { \varphi } / 4 \pi \rangle / \langle P \rangle is \alpha \sim 0.05 in the hot torus ( T _ { out } \sim 9.5 \times 10 ^ { 9 } { K } at 50 r _ { s } ) and \alpha \sim 0.01 in the cool torus ( T _ { out } \sim 1.1 \times 10 ^ { 9 } { K } at 35 r _ { s } ) .
In the cool model , a constant angular momentum inner torus is formed around 4 - 8 r _ { s } .
This inner torus deforms itself from a circle to a crescent quasi-periodically .
During this deformation , the mass accretion rate , the magnetic energy and the Maxwell stress increase .
As the magnetic energy is released , the inner torus returns to a circular shape and starts the next cycle .

Power spectral density ( PSD ) of the time variation of the mass accretion rate in the cool model has a low frequency peak around 10 { Hz } when we assumed a 10 M _ { \odot } black hole .
The PSD of the hot model is flat in 1 - 30 { Hz } .
The slope of the PSD in the cool model is steeper than that in the hot model in 30 - 100 { Hz } .
The mass outflow rate in the low temperature model also shows quasi-periodic oscillation .
Intermittent outflows are created in both models .
The outflow speed is 0.01 c - 0.05 c .
The mass outflow rate is comparable to the mass accretion rate \dot { M } at 2.5 r _ { s } in the high temperature model and about 0.02 \dot { M } in the low temperature model .