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991.
A mathematical study via variational convergence of a periodic distribution of classical linearly elastic thin plates softly abutted together shows that it is not necessary to use a different continuum model nor to make constitutive symmetry hypothesis as starting points to deduce the Reissner–Mindlin plate model. 相似文献
992.
Christian Rein Steen Nissen Mariusz Grzelakowski Morten Meldal 《Journal of polymer science. Part A, Polymer chemistry》2016,54(13):2032-2039
A facile click chemistry method of immobilizing surface‐functionalized polymer vesicles on casted polymeric PAN substrates is described. Microporous PAN membranes were subjected to hydrochloric acid hydrolysis to obtain surface carboxylates. The carboxylic groups were activated with EDC/NHS‐solution and were then reacted with propargylamine to introduce alkyne groups for CuAAC reactions. The alkyne functionality of the modified membrane surface was verified by reaction with an azide functional click dye both before and after the immobilization of azide‐functionalized ABA vesicles. The efficient postfunctionalization of the membrane with alkyne allowed quantitative coverage of the membrane surface with a polymersome monolayer, as confirmed by immobilization of polymerzomes loaded with a fluorescent dye. Polymersome monolayers immobilized on alkyne functionalized PAN‐membranes were characterized by cryo‐SEM and monolayers were confirmed by atom force microscopy. These methods opens up new avenues for preparing membrane based filtration and sensor technologies. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 2032–2039 相似文献
993.
994.
Patrick Jungkunz Christian J. Darken 《Computational & Mathematical Organization Theory》2011,17(3):229-250
Models of eye movements of an observer searching for human targets are helpful in developing accurate models of target acquisition
times and false positive detections. We develop a new model describing the distribution of gaze positions for an observer
which includes both bottom-up (salience) and top-down (task dependent) factors. We validate the combined model against a bottom-up
model from the literature and against the bottom up and top down parts alone using human performance data on stationary targets.
The new model is shown to be significantly better. The new model requires a large amount of data about the terrain and the
target that is obtained directly from the 3D simulation through an automated process. 相似文献
995.
The authors propose a method for the extraction of material parameter and thickness information from sub-100-μm thin samples using non-differential transmission terahertz time domain spectroscopy. The approach relies on an additional Fourier transform of the frequency dependent material parameters to a quasi space regime. In this quasi space, periodic Fabry-Perot oscillations from the frequency domain, which originate from multiple reflections inside the sample, correspond to discrete peaks. By iterative minimization of these peaks, the highly precise thickness information along with the refractive index and absorption coefficient of the sample can be determined. Experimental verification of the approach is also provided. 相似文献
996.
Christian Bauer 《Mathematical Social Sciences》2011,62(2):126-129
An individual’s optimal behavior in a continuous-time sequential job search model with savings and CARA preferences is characterized analytically. I isolate the effects of limited borrowing and nonnegative consumption as well as risk aversion on the reservation wage by using a system of ordinary differential equations. 相似文献
997.
We describe elementary transformations between minimal models of rational surfaces in terms of unprojections. These do not fit into the framework of Kustin–Miller unprojections as introduced by Papadakis and Reid, since we have to leave the world of projectively Gorenstein varieties. Also, our unprojections do not depend on the choice of the unprojection locus only, but need extra data corresponding to the choice of a divisor on this unprojection locus. 相似文献
998.
999.
We proved in an earlier work that any existence variety of regular algebras is generated by its simple unital Artinian members,
while any existence variety of Arguesian sectionally complemented lattices is generated by its simple members of finite length.
A characterization of the class of simple unital Artinian members [members of finite length, respectively] of such varieties
is given in the present paper. 相似文献
1000.
Christian Fabiansen Charles W. Yaméogo Sarita Devi Henrik Friis Anura Kurpad Jonathan C. Wells 《Isotopes in environmental and health studies》2017,53(4):344-355
Childhood malnutrition is highly prevalent and associated with high mortality risk. In observational and interventional studies among malnourished children, body composition is increasingly recognised as a key outcome. The deuterium dilution technique has generated high-quality data on body composition in studies of infants and young children in several settings, but its feasibility and accuracy in children suffering from moderate acute malnutrition requires further study. Prior to a large nutritional intervention trial among children with moderate acute malnutrition, we conducted pilot work to develop and adapt the deuterium dilution technique. We refined procedures for administration of isotope doses and collection of saliva. Furthermore, we established that equilibration time in local context is 3?h. These findings and the resulting standard operating procedures are important to improve data quality when using the deuterium dilution technique in malnutrition studies in field conditions, and may encourage a wider use of isotope techniques. 相似文献