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11.
Minna Karstunen Harald Krenn Simon J. Wheeler Mirva Koskinen Rachid Zentar 《Canadian Metallurgical Quarterly》2005,5(2):87-97
This paper investigates the influence of anisotropy and destructuration on the behavior of a test embankment on soft clay. The test embankment at Murro, Finland, was commissioned in 1993 by the Finnish Road Administration and has been monitored for over 10?years. The construction and consolidation of Murro test embankment is analyzed with finite element method using three different constitutive models to represent the soft soil. The results are compared with field observations. The constitutive models used include two recently proposed constitutive models, namely S-CLAY1 that accounts for initial and plastic strain induced anisotropy and its extension, called S-CLAY1S. The S-CLAY1S model accounts, additionally, for interparticle bonding and degradation of bonds. For comparison, the test embankment is also analyzed using the isotropic Modified Cam Clay model. The simulations demonstrate that for this type of problem, it is important to account for the anisotropy, whereas destructuration appears to have less influence on predicted deformations. However, only a model incorporating destructuration can explain the decrease in undrained shear strength during consolidation that was measured in field. 相似文献
12.
We present a new solver for coupled nonlinear elliptic partial differential equations (PDEs). The solver is based on pseudo-spectral collocation with domain decomposition and can handle one- to three-dimensional problems. It has three distinct features. First, the combined problem of solving the PDE, satisfying the boundary conditions, and matching between different subdomains is cast into one set of equations readily accessible to standard linear and nonlinear solvers. Second, touching as well as overlapping subdomains are supported; both rectangular blocks with Chebyshev basis functions as well as spherical shells with an expansion in spherical harmonics are implemented. Third, the code is very flexible: The domain decomposition as well as the distribution of collocation points in each domain can be chosen at run time, and the solver is easily adaptable to new PDEs. The code has been used to solve the equations of the initial value problem of general relativity and should be useful in many other problems. We compare the new method to finite difference codes and find it superior in both runtime and accuracy, at least for the smooth problems considered here. 相似文献
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Harald Rohm und Veronika Veits 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1989,189(6):538-543
Zusammenfassung Die in den USA entwickelte sensorische Texturprofilanalyse stellt die aussagestärkste Methode zur quantitativen und qualitativen Bewertung der Texturunterschiede von Lebensmitteln dar. Vor der Anwendung in Regionen mit anderen Konsumgewohnheiten bedarf sie jedoch einer entsprechenden Adaptierung. Mitteilung 1 berichtet über modifizierte standardisierte Intensitätsskalen zur quantitativen Einstufung der mechanischen Textureigenschaften Festigkeit, Brüchigkeit, Kaubarkeit, weichelastisches Verhalten, Viskosität und Adhäsivität. Die Anpassung an das österreichische Lebensmittelspektrum erfolgte mittels rheologischer Vorprüfungen potentieller Standardpunkte und anschließender Fixierung der Normskalen durch ein geschultes Prüferpanel unter guter Korrelation zwischen instrumentellen und sensorischen Prüfungen.
Adaption of sensory texture profile analysis 1. Scaling of mechanical properties
Summary Texture profile analysis, originally developed in the United States, represents the most complete system of both quantitative and qualitative sensory texture measurements of foodstuffs. Due to regionally varying habits of consumption, an adequate adaptation is necessary prior to application. This paper deals with the evaluation of the mechanical properties firmness, brittleness, chewiness, gumminess, viscosity and adhesiveness. Modifications of standard rating scales for typical Austrian food materials are reported. Rheological examination of commodities was followed by final establishment of standard scales with a trained panel. Good correlation between instrumental and sensory results was obtained.相似文献
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Erik Benkler Andreas G. Steffan Harald R. Telle 《Photonics Technology Letters, IEEE》2007,19(5):267-269
We demonstrate a novel synchronization scheme for optical sampling which is based on a nonstandard phase-locked loop (PLL). Phase comparison is performed at a 10-GHz optical time-division-multiplexing (OTDM) base rate, thus avoiding ultrafast detectors and electronics. The employed frequency-offset PLL allows synchronous sampling of OTDM signals (or any other signals with bit rates given by integer multiples of the base rate), which would be impossible using a standard PLL. This provides a higher degree of flexibility for problem-specific sweeping than asynchronous sampling 相似文献
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Wolfgang Stadler Tilo Brodbeck Reinhold Grtner Harald Gossner 《Microelectronics Reliability》2009,49(9-11):1079-1085
Integrated circuits (ICs) are qualified for their electrostatic discharge (ESD) robustness according to the well-known IC ESD standards Human Body Model, Machine Model, and Charged Device Model in order to guarantee safe handling in ESD protected areas. For electronic systems like mobile phones which are in direct use by consumers, certain robustness against system level ESD is demanded, too. As the ESD test methods of device and system level stress are completely different (waveforms, stress application, operating condition of the DUT, etc.), correlations between models of both worlds are difficult to establish. Therefore, the system vendors more and more demand a specified ESD robustness for devices (ICs) according to an ESD system level standard. Testing ICs to a system level ESD standard requires careful considerations; first ideas are summarized in the new Standard Practice “Human Metal Model” of the ESDA/ANSI. However, the approach of deriving system ESD robustness from IC robustness is currently too much simplified and bears severe potential risks. Nevertheless, there are methodologies and approaches to use IC ESD characterization for defining ESD protection concepts for systems. Appropriate high-current characterization of ICs can be the cornerstone for a successfully optimized system ESD protection. 相似文献
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Hendrik Voigt Aaron Rigoni Evgeniy Boltynjuk Mohammed Reda Chellali Bonnie Tyler Harald Rösner Sergiy Divinski Horst Hahn Gerhard Wilde 《Advanced functional materials》2023,33(44):2302386
Comprehensive analyses of the atomic structure using advanced analytical transmission electron microscopy-based methods combined with atom probe tomography confirm the presence of distinct glass–glass interfaces in a columnar Cu-Zr nanoglass synthesized by magnetron sputtering. These analyses provide first-time in-depth characterization of sputtered film nanoglasses and indicate that glass–glass interfaces indeed present an amorphous phase with reduced mass density as compared to the neighboring amorphous regions. Moreover, dedicated analyses of the diffusion kinetics by time-of-flight secondary ion mass spectroscopy (ToF SIMS) prove significantly enhanced diffusivity, suggesting fast transport along the low density glass–glass interfaces. The present results further indicate that sputter deposition is a feasible technique for reliable production of nanoglasses and that some of the concepts proposed for this new class of glassy materials are applicable. 相似文献