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11.
W. Hahn  K. Mohr  U. Schauer 《Computing》1985,34(4):375-379
Methods are described for solving a system of linear equations with error bounds. Rectangular and spherical intervals ofR n are used combined. The objective is to get guaranteed accuracy with a minimal effort of computing time.  相似文献   
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Formation of Cocoa Aroma from Its Precursors Isolation and chemical composition of a highly purified mixture of aroma-precursors from raw cocoa were extensively studied and the alterations due to heating at roasting temperatures were followed quantitatively. Cocoa aroma is formed in the course of a Maillard reaction between amino acids and reducing sugars. Participation of oligopeptides in the alterations that are specific for the process of roasting could be detected for the first time. From the high-boiling components present in the reaction product, a fraction having the typical cocoa flavour could be isolated and resolved by gas chromatography. The consequences of these observations on the technology of roasting of cocoa are discussed.  相似文献   
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Based on the example of PE-LD grades and on model substances obtained by preparative fractionation (fractions in the molecular weight range M?w = 1.2 ? 390·104 g/mol), comprehensive investigations regarding the problems of structure/properties have been carried out. The correlations of M?w with 15 physical and application technological perameters have been investigated taking into account the reaction mechanism during the manufacturing of PE-LD in the tubular and agitated autoclave reactor, resulting in the formation of so-called primary structure perameters M?n, M?w, molar mass distribution, short chain branching and long chain branching. For the interpretation of the results, among other factors, also the morphological conditions have been taken into consideration, which in connection with the molecular parameters reveal — for specific M?w-ranges — strong changes and saturation ranges, resp., for the physical and application technological properties.  相似文献   
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Isogeometric analysis based on non-uniform rational B-splines (NURBS) as basis functions preserves the exact geometry but suffers from the drawback of a rectangular grid of control points in the parameter space, which renders a purely local refinement impossible. This paper demonstrates how this difficulty can be overcome by using T-splines instead. T-splines allow the introduction of so-called T-junctions, which are related to hanging nodes in the standard FEM. Obeying a few straightforward rules, rectangular patches in the parameter space of the T-splines can be subdivided and thus a local refinement becomes feasible while still preserving the exact geometry. Furthermore, it is shown how state-of-the-art a posteriori error estimation techniques can be combined with refinement by T-splines. Numerical examples underline the potential of isogeometric analysis with T-splines and give hints for further developments.  相似文献   
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It is a well-known fact that Hebbian learning is inherently unstable because of its self-amplifying terms: the more a synapse grows, the stronger the postsynaptic activity, and therefore the faster the synaptic growth. This unwanted weight growth is driven by the autocorrelation term of Hebbian learning where the same synapse drives its own growth. On the other hand, the cross-correlation term performs actual learning where different inputs are correlated with each other. Consequently, we would like to minimize the autocorrelation and maximize the cross-correlation. Here we show that we can achieve this with a third factor that switches on learning when the autocorrelation is minimal or zero and the cross-correlation is maximal. The biological counterpart of such a third factor is a neuromodulator that switches on learning at a certain moment in time. We show in a behavioral experiment that our three-factor learning clearly outperforms classical Hebbian learning.  相似文献   
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The Morse-Smale complex is an efficient representation of the gradient behavior of a scalar function, and critical points paired by the complex identify topological features and their importance. We present an algorithm that constructs the Morse-Smale complex in a series of sweeps through the data, identifying various components of the complex in a consistent manner. All components of the complex, both geometric and topological, are computed, providing a complete decomposition of the domain. Efficiency is maintained by representing the geometry of the complex in terms of point sets.  相似文献   
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<正>“Halle 2020”是Frankenthal市水泵和阀门生产厂KSB公司的一个扩建项目。这一项目不仅仅增加了KSB公司的生产面积,而且也扩展了KSB公司物流中心高架立体库的现代化和存储能力。Viastore公司收到了重建工厂的合同。  相似文献   
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