In this paper, a pyramid neural network is applied to characterize the hepatic parenchymal diseases in ultrasonic B-scan texture. The cirrhotic parenchymal diseases are classified into 4 types ...according to the size of hypoechoic nodular lesions. The B-mode patterns are wavelet transformed, and then the compressed data are fed into a pyramid neural network to diagnose the type of cirrhotic disease. Compared with the 3-layer neural networks, the performance of the proposed pyramid neural network is improved by utilizing the lower layer effectively. The simulation results show that the proposed system is suitable for diagnosis of cirrhosis.
This paper presents a tracking control design method for nonminimum phase systems based on multirate control. Traditionally, perfect tracking control schemes cannot be applied to nonminimum phase ...plants because of unstable pole-zero cancellations. Although methods of zero assignment based on multirate control and the method of state matching using multirate feedforward control to realize perfect tracking control have been proposed, the oscillation restraint and the feasibility in nonminimum phase systems cannot be satisfied at same time. We propose a method using the difference of state variables to generate a smooth desired state variable trajectory in the discrete-time systems. The techniques we proposed are applicable to nonminimum phase discrete-time systems and the oscillations between the sampling points are restrained well. Finally, computer simulations and experiment results based on magnetic levitation apparatus are presented.
The adaptive Volterra filter (AVF), based on the discrete Volterra series, has been used to identify a nonlinear system, remove nonlinear distortion etc. Since AVF is an extension of conventional ...linear digital filters, the algorithms used in linear filters are easily used in AVF, and AVF is enough approximate to complicated systems due to its general function expansion. However, when long filter length is considered, or when high-order nonlinear characteristics are filtered, the computational complexity of AVF becomes extremely large and may be infeasible in real time applications with today's technology. This paper presents a type of parallel adaptive Volterra filter (PAVF) to decrease the calculation complexity. Finally, to demonstrate the effectiveness of the proposed method, several results of computer simulation are presented.
A 74-year-old man who went into shock following an acute hemomediastinum and left hemothorax was operated on. Postoperative angiographies revealed a saccular aneurysm of the left bronchial artery of ...2.0 cm in diameter. Sixty days after the initial operation, the aneurysm was resected under F-F bypass. A saccular aneurysm was found at the root of the left bronchial artery, which had a very short segment between the aneurysm and the aorta. Pathological study of aneurysm revealed thinning of the wall and lack of tunica media.
We have investigated the stability of giant unilamellar vesicles (GUVs) and large unilamellar vesicles (LUVs) of lipid membranes in the liquid-ordered phase (lo phase) against a detergent, Triton ...X-100. We found that in the presence of high concentrations of Triton X-100, the structure of GUVs and LUVs of dipalmitoyl-PC (DPPC)/cholesterol (chol) and sphingomyelin (SM)/chol membranes in the lo phase was stable and no leakage of fluorescent probes from the vesicles occurred. We also found that ether-linked dihexadecylphosphatidylcholine (DHPC) membranes containing more than 20 mol% cholesterol were in the lo phase, and that DHPC/chol-GUV and DHPC/chol-LUV in the lo phase were stable and no leakage of internal contents occurred in the presence of Triton X-100. In contrast, octylglucoside solution could easily break these GUVs and LUVs of the lo phase membranes and induced internal contents leakage. These data indicate that GUVs and LUVs of the lo phase membranes are very valuable for practical use.
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