Learn More
Doppler ultrasound systems, used for the noninvasive detection of the vascular diseases, normally employ a high-pass filter (HPF) to remove the large, low-frequency components from the vessel wall from the blood flow signal. Unfortunately, the filter also removes the low-frequency Doppler signals arising from slow-moving blood. In this paper, we propose to(More)
A modified graph cut was proposed under the elliptical shape constraint to segment cervical lymph nodes on sonograms, and its effect on the measurement of short axis to long axis ratio (S/L) was investigated by using the relative ultimate measurement accuracy (RUMA). Under the same user inputs, the proposed algorithm successfully segmented all 60 sonograms(More)
To overcome the premature convergence of particle swarm optimization (PSO), we introduce a sociological conception, called family, into the PSO. Family is a common activity form of life. Each family in a population usually competes for the resource with other family and enhances collaboration among family members. We introduced this sociological conception(More)
For the discretization of particles in particle swarm optimization (PSO), we have proposed the family PSO (FPSO) previously. To further study the internal structure of FPSO, this paper defined two kinds of relationships between particles: equal relationship (ER) and generational relationship (GR). FPSO of equal relationship (ER-FPSO) and FPSO of(More)
In order to reduce the observer variability in radiographic scoliosis assessment, a computer-aided system was developed. The system semi-automatically measured the Cobb angle and vertebral rotation on posteroanterior radiographs based on Hough transform and snake model, respectively. Both algorithms were integrated with the shape priors to improve the(More)
A computer simulation model based on an analytic flow velocity distribution is proposed to generate Doppler ultrasound signals from pulsatile blood flow in the vessels with various stenosis degrees. The model takes into account the velocity field from pulsatile blood flow in the stenosed vessels, sample volume shape and acoustic factors that affect the(More)
In our previous study, the family particle swarm optimization (FPSO) was proposed. In this study, we investigate the direction of the FPSO. To improve particles' abilities of moving to the global optimization position and to accelerate the convergence of FPSO, we defined the direction coefficient and proposed the directional FPSO (d-FPSO). In a family, the(More)