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101.
102.
Venting is the common safety measure to protect plant equipment against excessive overpressure. So far, scenarios in which particles were part of the system and should have been accounted for did ignore their presence; the scenarios were treated like a two-phase system. Current research shows that particles can have a major influence on the venting behaviour. Experimental results indicate that particles affect level swell and relief flow especially of foamy systems. Based on those results four different layers of influence of the particle have been identified and are presented in a first model. Based on this model recommendations for the development of new and more complex models are given. 相似文献
103.
Experiments in behavior composition 总被引:2,自引:0,他引:2
Jana Ko
eck Henrik I Christensen Ruzena Bajcsy 《Robotics and Autonomous Systems》1997,19(3-4):287-298
104.
Henrik P. Porte Dmitry Turchinovich Saydulla Persheyev Yongchang Fan Mervyn J. Rose Peter Uhd Jepsen 《Journal of Infrared, Millimeter and Terahertz Waves》2011,32(7):883-886
Black silicon is produced by laser annealing of a-Si:H films. During annealing, silicon microstructures are formed on the
surface. We use time-resolved terahertz spectroscopy to study the photoconductivity dynamics in black silicon. We find that
when a copper film is deposited on top of the a-Si:H layer prior to laser annealing, the carrier lifetime of black silicon
is significantly reduced. 相似文献
105.
106.
107.
Giulio Giovannetti Francesca Frijia Simona Attanasio Luca Menichetti Valentina Hartwig Nicola Vanello Jan Henrik Ardenkjaer-Larsen Daniele De Marchi Vincenzo Positano Rolf Schulte Luigi Landini Massimo Lombardi Maria Filomena Santarelli 《Measurement》2013
Hyperpolarized 13C magnetic resonance spectroscopy in pig models enables cardiac metabolism assessment and provides a powerful tool for heart physiology studies, although the low molar concentration of derivate metabolites gives rise to technological limitations in terms of data quality. The design of dedicated coils capable of providing large field of view with high Signal-to-Noise Ratio (SNR) data is of fundamental importance. 相似文献
108.
A probabilistic fracture mechanics method is presented and applied to glulam beams with holes. The method is based on a combination of Weibull weakest link theory and a mean stress method which is a generalization of linear elastic fracture mechanics. Combining these two methods means that the global strength will be governed by both fracture energy and material strength and also that the stochastic nature of the material properties are taken into account. The probabilistic fracture mechanics method is evaluated by comparison to experimental test results. The method shows good ability to predict strength, with the exception of very small beams where the capacity is overestimated. The comparison to experimental tests deals also with other methods for strength analysis including code design methods. 相似文献
109.
The dilution and spreading of dispersed oil in produced water from 95 offshore oil production platforms in the North Sea area have been calculated with the numerical model PROVANN. Amounts of releases are specified on a yearly basis. The simulations include simultaneous calculations for all sources expanding over a time period of one year. The calculations use a three-dimensional and time-varying current field for the North Sea generated by a hydrodynamic model.The PROVANN calculations are verified by testing the model's ability to reproduce analytical solutions of the diffusion–advection equation. The model is further verified by comparing calculated concentrations with field measurements on a regional scale. 相似文献
110.
During the last two decades the major food safety problems in Denmark, as determined by the number of human patients, has been associated with bacterial infections stemming from meat products and eggs. The bacterial pathogens causing the majority of human infections has been Salmonella and Campylobacter, and to a lesser extent Yersinia, Escherichiacoli O157 and Listeria. Danish initiatives to improve the safety of meat products have focused on the entire production chain from the farm to the consumer, with a special emphasis on the pre-harvest stage of production. The control of bacterial pathogens which are resistant to antibiotics has been a new area of attention in the recent decade, and recently, the increasing globalization of the domestic food supply has called for a complete rethinking of the national food safety strategies. The implementations of a “case-by-case” risk assessment system, as well as increased international collaboration on surveillance, are both elements in this new strategy. 相似文献