Phase unwrapping method based on improved quadratic pseudo-Boolean optimization.

Maximum a posteriori estimation of Markov random fields (MRFs) is a popular research area in computer vision, and many algorithms have been proposed to deal with these types of problems. The phase-unwrapping problem is modeled as the optimization of MRFs in this research, and the binary algorithm, improved quadratic pseudo-Boolean optimization, is utilized to solve the phase-unwrapping problem. Both the interferometric phases generated from the commonly used computer simulated surfaces and also real terrains are researched in the experimental section, and the unwrapping results are compared.

Experimental study of the influence of refraction on underwater three-dimensional reconstruction using the SVP camera model.

In an underwater imaging system, a perspective camera is often placed outside a tank or in waterproof housing with a flat glass window. The refraction of light occurs when a light ray passes through the water-glass and air-glass interface, rendering the conventional multiple view geometry based on the single viewpoint (SVP) camera model invalid. While most recent underwater vision studies mainly focus on the challenging topic of calibrating such systems, no previous work has systematically studied the influence of refraction on underwater three-dimensional (3D) reconstruction.

[Significances of plasma levels of neuropeptide Y pre- and post-treatment in patients with decompensated cirrhosis and ascites].

Objective: To observe changes of plasma neuropeptide Y(NPY) level in ascitic patients with decompensated cirrhosis pre- and post-treatment, there fore to understand the correlation of NPY with liver function and ascitic formation.

Methods: NPY plasma levels in 20 patients with decompensated cirrhosis and ascites were detected by radioimmunological assay.

Results: Plasma NPY levels in patients with cirrhotic ascites were significantly lower than those in normal subjects(P < 0.