摘要:
A method is provided to improve the frame-rate in color-flow ultrasound imaging using simultaneous spatially-distinct transmit beams with one or more frequency bands per transmit beam. Pulses of different center frequencies are used simultaneously in different (lateral and/or elevational) directions, thereby reducing the scanning time and improving the frame-rates. Optionally, a multi-modal pulse is used, and flow is estimated separately for the different frequencies. The flow estimates for these pulses are appropriately combined to improve low-velocity sensitivity and to reduce aliasing. A flow sample count with two or more different pulse repetition intervals can be used to further improve low-flow sensitivity and minimize aliasing.
摘要:
Velocity scale is automatically determined for ultrasound imaging. Receive signals corresponding to different pulse repetition intervals are used to estimate velocities. The different velocities are used to determine the velocity scale. For example, the different pulse repetition intervals are obtained by selecting different sets of signals from a group of signals for a scan line. As another example, the different pulse repetition intervals are obtained by transmitting for a scan line with changing, such as increasing, pulse repetition intervals. The lower pulse repetition interval of a pair of intervals associated with a sign change in the phase is used for the velocity scale. In yet another example, at least two demodulation frequencies are used for a broadband transmit in at least two sets, each set with a different pulse repetition interval. Velocities are estimated for a greater number of pulse repetition intervals than transmitted using the broadband pulses.
摘要:
Adaptive volume rendering is provided for medical diagnostic ultrasound. The opacity of B-mode data is set relative to the opacity of Doppler data. The opacities for the different types of data are set as a function of ray depth. For example, the opacity of B-mode data near a tissue border is set to be more opaque than for tissue away from the border, and the opacity for flow data near a flow border is set to be less opaque than for flow away from the border. An image is rendered using a rendering parameter set as a function of ray depth, B-mode information and Doppler information. Other processes for enhancing and/or using rendering may be used.
摘要:
Motion imaging in medical diagnostic ultrasound is adaptive. Clutter or threshold processing adapts as a function of data for different locations or for different times. Spatial filtering adapts as a function of data at different spatial locations at a same time. The steering angle may be set as a function of region based on the vessel orientation and maximum velocity. The region of interest for motion imaging may be expanded to counteract, at least in part, a shift due to the steering angle.
摘要:
A filament forming apparatus and cooling apparatus for and method of cooling a filament forming area beneath a bushing is disclosed. The cooling apparatus includes a manifold with a cooling fluid channel formed therein, and a plurality of hollow cooling fins operatively coupled to the manifold. A cooling fluid flows into the manifold, through first and second fluid flow channels in the cooling fins, and back into the manifold from which it is subsequently discharged. Each cooling fin includes a plurality of divider members between the first and second fluid flow channels. Adjacent divider members define a small channel between each other. The cooling fluid flows from the first fluid flow channel through the small channels to the second fluid flow channel. The overall heat transfer coefficient is increased due to the forced convection of the surfaces of the cooling fin using a single-phase fluid passing through the cross-sectional area of a small channel. Further, divider members increase the surface area contact between the cooling fluid flow and the cooling fin walls. The cooling fluid in the fin may absorb enough heat to achieve two phase, liquid and vapor, flow. The bottom wall and/or side walls of the fin includes a plurality of holes through which the liquid and/or vapor in the fin may spray into the filament forming area. This spray enhances the cooling and quenching of the glass filaments in the filament forming area.
摘要:
An apparatus is provided for producing continuous glass filaments. The apparatus comprises a feeder (20) for supplying streams of molten glass to be drawn into continuous filaments, a drawing device (40) adapted to draw the streams into the filaments, and heat removal apparatus (50) located adjacent to the feeder for transferring energy in the form of heat away from a filament forming area adjacent to the feeder. The heat removal apparatus includes first and second manifolds (52a, 54) through which a cooling fluid circulates, a plurality of fins (56) having first and second ends (56a and 56b) and interface material (58). The first ends of the fins are associated with the first manifold and the second ends are positioned adjacent to the second manifold. The first ends may be fixedly connected to the first manifold. The interface material is interposed between the second manifold and the second ends to provide a path for energy in the form of heat to flow from the fins to the second manifold.
摘要:
A method and apparatus for forming fibers includes a spinner having a porous member positioned therein in a region normally covered by molten glass, and means for supplying a gas to the porous member under pressure sufficient to cause introduction of the gas into the molten mineral material.
摘要:
Motion imaging in medical diagnostic ultrasound is adaptive. Clutter or threshold processing adapts as a function of data for different locations or for different times. Spatial filtering adapts as a function of data at different spatial locations at a same time. The steering angle may be set as a function of region based on the vessel orientation and maximum velocity. The region of interest for motion imaging may be expanded to counteract, at least in part, a shift due to the steering angle.
摘要:
Diagnostic ultrasound flow imaging is performed with coded excitation pulses. Due to the use of frequency coded excitation pulses, flow information may suffer from spatial misregistration and estimate errors. Spatial position shift in flow data is offset for alignment with B-mode or other imaging. The flow estimates are compensated for the imaging center frequency variation with depth. The wide bandwidth information available due to coded excitation may allow anti-aliasing by estimating velocities from two frequency bands.
摘要:
The present invention is directed toward an apparatus and method for determining localized strain in a target body by identifying sets of features in reflected echo sequences and by comparing sets of features to determine time shift values between features.