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71.
72.
Cheng-Chang Lien Chung-Lin Huang Jhy-Gau Chen 《IEEE transactions on image processing》1997,6(5):694-702
This paper introduces the complex subband transform (CST) that can be applied for both subband signal decomposition and motion estimation, which are the two major processes in subband-based image sequence coding. In the experiments, we compare the CST-based subband motion compensation with conventional block matching motion compensation, and find that the former has (i) higher peak signal-to-noise ratio (PSNR) of the reconstructed images and (ii) lower prediction error entropy of the motion vectors. 相似文献
73.
Chun Chen Chuen-Der Lien Yean-Woei Kiang 《Antennas and Propagation, IEEE Transactions on》1982,30(3):483-486
A mathematical derivation is presentcd to establish the discrete energy conservation law and reciprocity relationship for explaining the insensitive phenomenon round in the previous investigations of a one-dimensional wave propagation problem. It is shown that there do exist certain discretized differential and variational systems which can preserve the energy conservation and reciprocity relationships. This then excludes the use of these relationships in error estimation. 相似文献
74.
75.
JJ Hwang KG Shyu JJ Chen YZ Tseng P Kuan WP Lien 《Canadian Metallurgical Quarterly》1993,104(3):861-866
To evaluate the usefulness of transesophageal echocardiography (TEE) in the treatment of critically ill patients, 80 patients (51 male and 29 female; mean age, 53 years) undergoing both transthoracic echocardiography (TTE) and TEE were studied in a 2-year period. Of these, 48 patients were studied in the ICU, while the other 32 patients were directly referred from the emergency departments. Indications for the study included suspected aortic dissection (34 patients), hemodynamic instability (22 patients), suspected cardiac source of embolism (11 patients), evaluation of the severity of mitral regurgitation (7 patients), and suspected infective endocarditis (6 patients). The probe was passed successfully in 78 of 80 attempts (98 percent). No significant complications were recorded during the transesophageal echocardiographic study. Transesophageal echocardiography provided critical information that was not obtained by TTE in 39 of 78 studies (50 percent, p < 0.005). Cardiac surgery was prompted by TEE findings in 14 patients (18 percent) and these findings were all confirmed at operation. Transesophageal echocardiography was a safe, well-tolerated, and valuable diagnostic approach for the rapid detection of specific cardiac abnormalities in patients with critical illness; TEE should be considered in the treatment of critically ill patients especially when TTE provided inadequate information. 相似文献
76.
Human milk fat is well absorbed despite its large concentration of long-chain saturated fatty acids (LCSFA), particularly palmitic acid. The superior absorption has been ascribed in part to the uncommonly high proportion of the palmitic acid in the sn-2 position of the triglycerides, 70% in human milk triglycerides compared with 10-15% in the fats and oils commonly used in infant formula blends. Colipase-dependent pancreatic lipase selectively hydrolyzes the fatty acids at the sn-1 and 3 positions, yielding free fatty acids and the 2-monoglyceride, which are absorbable. Free palmitic acid, but not monopalmitin, can be lost as calcium soaps in the feces. The present study demonstrated that mixtures of coconut oil and palm olein are better absorbed by rats if the proportion of LCSFA in the sn-2 position is increased by the process of chemical randomization, in which the fatty acids of the native oils are redistributed equally to all three positions in the rearranged triglycerides. The fecal excretion of total fatty acids, essentially LCSFA, from the mixtures in which the oils were randomized together (corandomized) was 30 to 60% less than from the mixtures of native oils. 相似文献
77.
We investigate the free-edge stresses in anisotropic bimaterials through the use of the free-edge stress intensity factor,
Kf. This requires a determination of the singularity order at the free-surface as well as a calculation of the near-field
stresses. We determine the order of the singularity for arbitrary free-surface orientation of the upper material using an
eigenvalue analysis for anisotropic bimaterials. The interfacial stresses are determined using a boundary element calculation
based on anisotropic, bimaterial Green's functions. The variation of Kf with free-surface orientation is determined. We find
that the free-edge singularity vanishes for certain angles dependent on the anisotropic elastic constants.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
78.
79.
Yeong-Jeu Sun Chang-Hua Lien Jer-Guang Hsieh 《Automatic Control, IEEE Transactions on》1998,43(5):674-677
In this paper, the global exponential stabilization for a class of uncertain nonlinear systems with control constraint is investigated. A bounded and continuous feedback control is constructed, under which the global exponential convergence for such systems can be guaranteed. A numerical example is also provided to illustrate the use of our main result 相似文献
80.
The normal phlebographic appearances of the left renal and left testicular veins are described, based upon the findings in 100 patients admitted because of confirmed or possible testicular tumor. The patients had no metastases demonstrated at foot lymphography, urography and phlebography of the inferior vena cava. 相似文献