No References!

Notation
The following symbols are used in this paper:

COR	=	correlation coefficient for each of three ADV receivers;
SNR	=	signal-to-noise ratio measured at ADV receivers;
$u$	=	velocity;
$\Delta u$	=	first derivative of velocity;
$\Delta^2 u$	=	Second derivative of velocity; and
$\alpha$	=	void fraction.

List of Figure Captions
Fig.1. Illustration of experimental set-up
Fig.2. The relationship between the void fraction $\alpha$ and time averaged correlation, COR and signal-to-noise ratio SNR ($\circ$: correlation, $*$: SNR).
Fig.3. Example of despiking by the two phase space methods
(a) True 3D phase space method
(b) Pseudo 3D phase space method (top-left:$u-\Delta u$, top-right: $\Delta u-\Delta^2 u$, bottom-left:$u-\Delta^2u$, bottom-right:time history of $u$)
Fig.4. Time history of $u$, correlation (COR) and signal-to-noise ratio (SNR)
(a) Velocity and correlation
(b) Velocity and SNR Fig.5. Relationship between velocity and correlation/SNR ($\alpha=0.6$%)
Fig.6. Valid data rate dependence on void fraction
(a) Normalized time averaged velocity
(b) Normalized standard deviation of velocity
Fig.7.The effects of despiking and low correlation filtering methods on the mean and turbulence characteristics of flow

Figure: Illustration of experimental set-up

Figure: The relationship between the void fraction $\alpha$ and time averaged correlation, COR and signal-to-noise ratio SNR ($\circ$: correlation, $*$: SNR).

Figure: Example of despiking by the two phase space methods

(a) True 3D phase space method

(b) Pseudo 3D phase space method (top-left:$u-\Delta u$, top-right: $\Delta u-\Delta^2 u$, bottom-left:$u-\Delta^2u$, bottom-right:time history of $u$)

Figure: Time history of $u$, correlation (COR) and signal-to-noise ratio (SNR)

Figure: Relationship between velocity and correlation/SNR ($\alpha=0.6$%)

(a) Velocity and correlation

Velocity and SNR

Figure: Valid data rate dependence on void fraction

Figure: The effects of despiking and low correlation filtering methods on the mean and turbulence characteristics of flow

(a) Normalized time averaged velocity

(b) Normalized standard deviation of velocity