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21.
XML hat sich als Sprache zur Definition von Dokumenten für den universellen Datenaustausch etabliert. XML-Schema erm?glicht
ausgefeilte Definitionen für XML-Dokumente und hat beste Chancen, die bisher eingesetzte DTD abzul?sen. Neben einer allgemeinen
Einführung geht dieser Beitrag auch auf verfügbare Produkte und neue M?glichkeiten der objektorientierten Softwareentwicklung
mit XML-Schema ein.
Vorschl?ge an Prof. Dr. Frank Puppe <puppe@informatik.uni-wuerzburg.de> oder Dieter Steinbauer <dieter.steinbauer@schufa.de>
Alle „Aktuellen Schlagw?rter” seit 1988 finden Sie unter: www.ai-wuerzburg.de/as 相似文献
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We solve the Kohn-Sham equations self-consistently in the local density approximation for spheroidal sodium clusters in the particle range 8 ≤ Z ≤ 40. We use a smooth fermi-like jellium density to simulate the influence of the ions in the surface region and obtain similar results as Ekardt and Penzar, but slightly different regions of prolate-to-oblate transitions. We present the systematics of potential energy curves with respect to transitions between oblate, prolate and spherical shapes. Shape transitions occur at particle numbers 12/14 (prolate/oblate), 18/20/22 (oblate/spherical/prolate) and 30/32 (prolate/oblate), which are in good agreement with experimental results. The quadrupole and hexadecupole overlap of the electron density with the jellium is investigated, showing a strong hexadecupole dependence for selected clusters. Collective dipole resonances are described in a simple sum rule approach, which reveals a double splitting according to the different resonance frequencies along the principal axes of the spheroid. The systematics of the resonance peaks for the larger clusters with Z ≥ 20 is in good agreement with experimental results. 相似文献
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Evaluating Liquefaction Strength of Partially Saturated Sand 总被引:1,自引:0,他引:1
A method is presented for evaluating the liquefaction strength of partially saturated sand using the compression wave velocity (P-wave velocity), a new indicator of saturation. Based on laboratory test results, an empirical correlation that relates the liquefaction strength with the pore pressure coefficient B is firstly proposed. The strength is defined as the cyclic stress ratio required to cause liquefaction at a specified number of cycles. With the aid of a theoretical relation between B and the P-wave velocity, an explicit correlation of more interest is then established between the liquefaction strength of sand and its P-wave velocity. A comparison of the predictions using this explicit correlation with laboratory measurements shows a satisfactory agreement. The significance of this method lies in that it makes it possible to evaluate the liquefaction strength of sand as affected by saturation through the measurement of P-wave velocity, which can be made not only in the laboratory but particularly in the field. 相似文献
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In their comments on the authors' article (see record 2003-10163-009), R. C. Serlin, B. E. Wampold, and J. R. Levin (see record 2003-10163-011) and P. Crits-Christoph, X. Tu, and R. Gallop (see record 2003-10163-010) took issue with the authors' suggestion to evaluate therapy studies with nested providers with a fixed model approach. In this rejoinder, the authors' comment on Serlin et al's critique by showing that their arguments do not apply, are based on misconceptions about the purpose and nature of statistical inference, or are based on flawed reasoning. The authors also comment on Crits-Christoph et al's critique by showing that the proposed approach is very similar to, but less inclusive than, their own suggestion. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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L Bauer B Bohle B Jahn-Schmid U Wiedermann A Daser H Renz D Kraft C Ebner 《Canadian Metallurgical Quarterly》1997,107(3):536-541
Several in vitro and in vivo studies indicate that application of high doses of dominant T cell epitopes can induce a state of antigen-specific non-responsiveness (anergy). In the present study, we developed a murine model of an allergic immune response to Bet v 1, the major birch pollen allergen. Mice were sensitized by injection of rBet v 1 and the allergic state was proven by the presence of allergen-specific IgE and positive immediate-type skin tests to Bet v 1. In epitope mapping experiments, an immunodominant T cell epitope of Bet v 1 in BALB/c mice was identified by the use of overlapping peptides. This peptide (BV 139) was subsequently employed for treatment. Two tolerization protocols were used: in one approach, the peptide was administered to naive mice before immunization (group BV139-S), in the second, already sensitized mice were treated (S-BV139). The results demonstrated that administering high doses of the dominant T cell epitope of Bet v 1 profoundly diminished T cell proliferation to the peptide in the BV139-S group, and to the peptide as well as to the whole protein in the S-BV139 group. Skin test reactivity to Bet v 1 was reduced in the BV139-S group. However, no differences in terms of specific antibody production between treated and untreated mice could be observed. This study provides evidence that administration of dominant T cell epitopes can down-regulate the allergen-specific T cell response. Proceeding on the assumption that the T lymphocyte response to allergens is crucial for the induction and maintenance of the allergic disease, a modulation of the immune response to allergens by treatment with T cell epitope peptides could represent a promising concept for immunotherapy in the future. 相似文献