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991.
Pantic-Tanner Z. Scott Savage J. Tanner D.R. Peterson A.F. 《Microwave Theory and Techniques》1998,46(2):178-184
The finite-element method (FEM) exhibits a reduced convergence rate when used for the analysis of geometries containing sharp edges where the electromagnetic field is singular. The convergence of the method can be-improved by introducing singular elements that model analytically predicted singular behavior. A number of authors have developed singular elements that are compatible with the scalar FEM. In this paper, we propose a new singular element that is compatible with edge-based vector finite elements and can cope with any order of singularity while preserving the sparsity of the FEM equations. Edge-based singular elements more correctly model singular fields and thus require fewer unknowns, while avoiding the introduction of spurious modes in the numerical solution. Numerical results verify that the convergence of the FEM is significantly improved 相似文献
992.
993.
994.
Textural evolution in electrodeposits is strongly affected by foreign species in the electrolyte and also by the co-deposition
of hydrogen. The effects of foreign species on textural development in electrodeposits were studied by employing a Monte Carlo
model. This model is based on physical principles and incorporates parameters which are used to control electrodeposition
processes. An attempt was made in the simulation to reflect the basic process of the deposit growth, and to identify the factors
responsible for the texture formation and its variation with the deposition condition. It is assumed that the texture of the
deposit results from the minimization of the free energy of the system. Based on this assumption, it was demonstrated that
the surface-energy anisotropy played an important role in the formation of fibre texture. In particular, the model can be
used to simulate textural evolution under the influence of adsorbed foreign species, because the surface-energy anisotropy
is modified by the adsorbed foreign species. Part I of the paper presents results of our studies on iron electrodeposition
with the emphasis on the effect of hydrogen adsorption on iron deposit texture. Relevant experimental results have also been
presented to corroborate the simulation study. Part II of the paper presents simulation studies of textural evolution in copper
deposits under the influence of adsorbed potassium and chloride ions.
This revised version was published online in November 2006 with corrections to the Cover Date. 相似文献
995.
Hartung J. Jacquin A. Pawlyk J. Rosenberg J. Okada H. Crouch P.E. 《Selected Areas in Communications, IEEE Journal on》1998,16(1):42-55
This paper describes a prototype video coding platform meant for the conception and testing of multimedia products such as next-generation videophones. The platform is largely based on ITU-T Recommendation H.263, with a number of additional object-oriented quality enhancement features which make it especially well suited for very low bit-rate coding of “head-and-shoulders” video material typical of real-time multimedia applications, video teleconferencing, and video telephony. These features consist of: (1) segmentation into objects of interest, (2) segmentation-based prefiltering, (3) model-assisted rate control, (4) adaptive vector quantization, and finally (5) segmentation-based postfiltering. In the spirit of Recommendation H.263, these enhancements are modular and can be selectively turned on or off, thereby enabling a wide variety of coding modes 相似文献
996.
An "Occam algorithm" learning model maintains a tentative hypothesis consistent with past observations and, when a new observation is inconsistent with the current hypothesis, updates to the next-simplest hypothesis consistent with all observations. In previous work, observations were assumed to be stochastically independent. This paper initiates study of such models under weaker Markovian assumptions on the observations, In the special case where the sequence of hypotheses satisfies a monotonicity condition, it is shown that the number of mistakes in classifying the first t observations is O(√t log 1/πi), where πi is the stationary probability of the initial state, i, of the Markov chain. 相似文献
997.
Guan L. Christou A. Halkias G. Barbe D.F. 《Electron Devices, IEEE Transactions on》1995,42(4):612-617
A model for the calculation of the current-voltage characteristics of strained In0.52Al0.48As/InxGa1-xAs on InP substrate High Electron Mobility Transistors (HEMT's), based on a variational charge control model, is presented. A polynomial fit of the two-dimensional electron gas (2DEG) density is used for the calculation of the current-voltage characteristics. The effect of strain is introduced into the 2DEG density versus gate voltage relation. Very good agreement between the calculated and measured I-V characteristics was obtained. In addition, our results show that, for an indium mole fraction of the InxGa1-xAs channel in the range 0.53-0.60, increasing the indium mole fraction lowers the threshold voltage and hence increases the drain current at the same gate bias 相似文献
998.
The paper presents a review of results concerning the aspartic proteinase cathepsin D and its role in tumor invasion and metastasis. Special attention was paid to the clinical prognostic value of cathepsin D determination in the breast cancer cytosol. 相似文献
999.
L Struillou M Fiks-Sigaud JH Barrier E Blat G Magadur-Joly 《Canadian Metallurgical Quarterly》1993,60(7-8):524-526
The authors report an exceedingly rare complication of rheumatoid arthritis, i.e. acquired hemophilia due to anti-factor VIII autoantibody production. Treatment with intravenous immune globulin ensured control of hemorrhagic manifestations by inducing a transient rise in factor VIII level. 相似文献
1000.
D Davis 《Canadian Metallurgical Quarterly》1993,24(4):50-51
Recommendations resulting from a JCAHO survey can be a true blessing as they force nursing departments to assess critically their professional practice and documentation systems. Systematic preparation, begun at least two years prior to the survey, includes Nursing Administration, a Nursing Documentation Task Force and all staff nurses. Educational consultants assigned to each unit bring nurses up-to-date on nursing process and nursing diagnosis. Mock surveys and cross-training in chart review prepare staff nurses for confident participation in the accreditation process. 相似文献