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41.
Mortar methods with dual Lagrange multiplier bases provide a flexible, efficient and optimal way to couple different discretization
schemes or nonmatching triangulations. Here, we generalize the concept of dual Lagrange multiplier bases by relaxing the condition
that the trace space of the approximation space at the slave side with zero boundary condition on the interface and the Lagrange
multiplier space have the same dimension. We provide a new theoretical framework within this relaxed setting, which opens
a new and simpler way to construct dual Lagrange multiplier bases for higher order finite element spaces. As examples, we
consider quadratic and cubic tetrahedral elements and quadratic serendipity hexahedral elements. Numerical results illustrate
the performance of our approach.
This work was supported in part by the Deutsche Forschungsgemeinschaft, SFB 404, C12, the Netherlands Organization for Scientific
Research and by the European Community's Human Potential Programme under contract HPRN-CT-2002-00286. 相似文献
42.
Meade Bolton C. Kraus T. Leone Link Heraeus Flügge A. Pfeiffer E. Esmarch Carl Fränkel von Sehlen's M. Hochstetter G. Bischof Alex Köbrich O. Kasper Dupré Joseph Klein John Henry Smith J. W. Mallet's E. Reichardt Mayrhofer Leopold Spiegel Katharine J. Williams W. Ramsay A. B. Cooper Baeseler Nobbe Will W. Knop C. W. Heaton Thomas Stevenson Odling Tidy Crookes P. T. Austen Austen und Francis A. Wilber 《Fresenius' Journal of Analytical Chemistry》1888,27(1):77-84
Ohne Zusammenfassung 相似文献
43.
Chen ML Penfold J Thomas RK Smyth TJ Perfumo A Marchant R Banat IM Stevenson P Parry A Tucker I Grillo I 《Langmuir : the ACS journal of surfaces and colloids》2010,26(23):18281-18292
The self-assembly in solution and adsorption at the air-water interface, measured by small-angle neutron scattering, SANS, and neutron reflectivity, NR, of the monorhamnose and dirhamnose rhamnolipids (R1, R2) and their mixtures, are discussed. The production of the deuterium-labeled rhamnolipids (required for the NR studies) from a Pseudomonas aeruginosa culture and their separation into the pure R1 and R2 components is described. At the air-water interface, R1 and R2 exhibit Langmuir-like adsorption isotherms, with saturated area/molecule values of about 60 and 75 ?(2), respectively. In R1/R2 mixtures, there is a strong partitioning of R1 to the surface and R2 competes less favorably because of the steric or packing constraints of the larger R2 dirhamnose headgroup. In dilute solution (<20 mM), R1 and R2 form small globular micelles, L(1), with aggregation numbers of about 50 and 30, respectively. At higher solution concentrations, R1 has a predominantly planar structure, L(α) (unilamellar, ULV, or bilamellar, BLV, vesicles) whereas R2 remains globular, with an aggregation number that increases with increasing surfactant concentration. For R1/R2 mixtures, solutions rich in R2 are predominantly micellar whereas solutions rich in R1 have a more planar structure. At an intermediate composition (60 to 80 mol % R1), there are mixed L(α)/L(1) and L(1)/L(α) regions. However, the higher preferred curvature associated with R2 tends to dominate the mixed R1/R2 microstructure and its associated phase behavior. 相似文献
44.
Methanolic extracts of the pods of Bobgunnia madagascariensis (Leguminosae) yielded four pentaglycosylated flavonoids, including the 3-O-α-l-rhamnopyranosyl(1→3)-α-l-rhamnopyranosyl(1→2)[α-l-rhamnopyranosyl(1→6)]-β-d-glucopyranoside-7-O-α-l-rhamnopyranosides of 3,5,7-trihydroxy-2-(4-hydroxyphenyl)-4H-benzopyran-4-one (kaempferol) and 3,5,7-trihydroxy-2-(3,4-dihydroxyphenyl)-4H-benzopyran-4-one (quercetin), which were characterized by a novel O-linked branched tetrasaccharide. Spectroscopic and chemical methods were used to determine the structures of the latter, which co-occurred with the corresponding β-d-galactopyranosyl isomers, and two saponins. Conformational isomerism of quercetin 3-O-α-l-rhamnopyranosyl(1→3)-α-l-rhamnopyranosyl(1→2)[α-l-rhamnopyranosyl(1→6)]-β-d-glucopyranoside-7-O-α-l-rhamnopyranoside was detected in solution by NMR, a phenomenon previously associated only with C-glycosylflavonoids. 相似文献
45.
R. N. Stevenson A. R.R. Carvalho J. J. Hope 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2011,61(2):523-529
We examine the theoretical limits of the generation of entanglement in a damped coupled ion-cavity system using jump-based
feedback. Using Raman transitions to produce entanglement between ground states reduces the necessary feedback bandwidth,
but does not improve the overall effect of the spontaneous emission on the final entanglement. We find that the fidelity of
the resulting entanglement will be limited by the asymmetries produced by vibrations in the trap, but that the concurrence
remains above 0.88 for realistic ion trap sizes. 相似文献
46.
Fabrice Gritti Irene Leonardis David Shock Paul Stevenson Andrew Shalliker Georges Guiochon 《Journal of chromatography. A》2010,1217(10):1589-1603
The performance of the new Kinetex-C18 column was investigated. Packed with a new brand of porous shell particles, this column has an outstanding efficiency. Once corrected for the contribution of the instrument extra column volume, the minimum values of the reduced plate heights for a number of low molecular weight compounds (e.g., anthracene and naphtho[2,3-a]pyrene) were between 1.0 and 1.3, breaking the legendary record set 3 years ago by Halo-C18 packed columns. The liquid-solid mass transfer of proteins (e.g., insulin and lyzozyme) is exceptionally fast on Kinetex-C18 much faster than on the Halo-C18 column. The different contributions of dispersion and mass transfer resistances to the column efficiency were determined and discussed. The possible reasons for this extremely high column efficiency are discussed. 相似文献
47.
W. L. Roberts K. P. Link T. M. Stevenson und J. S. Clayton 《Fresenius' Journal of Analytical Chemistry》1943,125(5-6):238-240
Ohne Zusammenfassung 相似文献
48.
An adaptive refinement procedure consisting of a localized error estimator and a physically based approach to mesh refinement is developed for the finite difference method. The error estimator is a variation of a successful finite element error estimator. The errors are estimated by computing an error energy norm in terms of discontinuous and continuous stress fields formed from the finite difference results for plane stress problems. The error measure identifies regions of high error which are subsequently refined to improve the result. The local refinement procedure utilizes a recently developed approach for developing finite difference templates to produce a graduated mesh. The adaptive refinement procedure is demonstrated with a problem that contains a well-defined singularity. The results are compared to finite element and uniformly refined finite difference results. 相似文献
49.
J A Simmons E G Freedman S B Stevenson L Chen T J Wohlgenant 《The Journal of the Acoustical Society of America》1989,86(4):1318-1332
The ability of the echolocating bat, Eptesicus fuscus, to detect a sonar target is affected by the presence of other targets along the same axis at slightly different ranges. If echoes from one target arrive at about the same delay as echoes from another target, clutter interference occurs and one set of echoes masks the other. Although the bat's sonar emissions and the echoes themselves are 2 to 5 ms long, echoes (of approximately equal sensation levels--around 15 dB SL) only interfere with each other if they arrive within 200 to 400 microseconds of the same arrival time. This figure is an estimate of the integration time of the bat's sonar receiver for echoes. The fine structure of the clutter-interference data reflects the reinforcement and cancellation of echoes according to their time separation. When clutter interference first occurs, the waveforms of test and cluttering echoes already overlap for much of their duration. The masking effect underlying clutter interference appears specifically due to overlap, not between raw echo waveforms, but between the patterns of mechanical excitation created when echoes pass through bandpass filters equivalent to auditory-nerve tuning curves. While the time scale of clutter interference is substantially shorter than the duration of echo waveforms, it still is much longer than the eventual width of a target's range-axis image expressed in terms of echo delay. 相似文献
50.
Meade Bolton C. Kraus T. Leone Link Heraeus Flügge A. Pfeiffer E. Esmarch Carl Fränkel von Sehlen's M. Hochstetter G. Bischof Alex Köbrich O. Kasper Dupré Joseph Klein John Henry Smith J. W. Mallet's E. Reichardt Mayrhofer Leopold Spiegel Katharine J. Williams W. Ramsay A. B. Cooper Baeseler Nobbe Will W. Knop C. W. Heaton Thomas Stevenson Odling Tidy Crookes P. T. Austen Austen Francis A. Wilber 《Analytical and bioanalytical chemistry》1888,27(1):77-84