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Olgierd Hryniewicz Zbigniew Nahorski Jörg Verstraete Joanna Horabik Matthias Jonas 《Climatic change》2014,124(3):519-534
A direct comparison among highly uncertain inventories of emissions is inadequate and may lead to paradoxes. This issue is of particular importance in the case of greenhouse gases. This paper reviews the methods for the comparison of uncertain inventories in the context of compliance checking. The problem is treated as a comparison of uncertain alternatives. It provides a categorization and ranking of the inventories which can induce compliance checking conditions. Two groups of techniques to compare uncertain estimates are considered in the paper: probabilistic and fuzzy approaches. They show certain similarities which are revealed and stressed throughout the paper. The group of methods most suitable for the compliance purpose is distinguished. They introduce new conditions for fulfilling compliance, depending on inventory uncertainty. These new conditions considerably change the present approach, where only the reported values of inventories are accounted for. 相似文献
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The effective procedure, which enables to discuss the dynamic response of Rayleigh beam resting on nonlinear viscoelastic foundation subjected to moving load, is developed. By employing the Adomian decomposition method in conjunction with coiflet expansion, the approximate closed form solution has been derived and condition for the convergence of the decomposition series has been introduced. To evaluate the accuracy of the approximate solution a local error index is defined. The presented new complex method is simple and efficient. The parametric study is performed and the influence of nonlinearity, load velocity, load frequency and the radius of gyration on the wave propagation in beam is investigated. The numerical results show that for the supercritical case, the linear model is stiffer giving rise to small displacement of the beam at the load passage. 相似文献
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Lene L. Delsett Patrick S. Druckenmiller
yvind Hammer Krzysztof Hryniewicz Espen M. Knutsen Maayke J. Koevoets Hans A. Nakrem Aubrey J. Roberts Jrn H. Hurum 《Geology Today》2019,35(1):20-25
In the Mesozoic seas, the apex predators were reptiles. From the Arctic archipelago of Svalbard, the Spitsbergen Mesozoic Research Group has excavated numerous well preserved marine reptile skeletons in order to understand the biology of these animals and the environment they lived in. The work of eleven field seasons has made this one of the largest and most productive palaeontological research projects in the high Arctic world‐wide. The initial eight seasons focused on one of the richest occurrences of Late Jurassic—earliest Cretaceous (c. 150–139 Ma) marine reptiles in the world, and nearly sixty specimens have been collected, together with a diverse assemblage of invertebrates, some of which are associated with methane seeps. The last three seasons were spent investigating events further back in time, as Spitsbergen preserves the remains from some of the first marine reptile radiations in the wake of the most devastating extinction in the history of the Earth, at the Permian–Triassic boundary (c. 252 Ma). 相似文献
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Z. Hryniewicz 《地震工程与结构动力学》1984,12(1):1-8
The intensity of shear waves in the model of a multilayered stratum, the material properties of which are random functions, is considered. The solutions for displacements and stresses are obtained for one layer and then the formulation is extended to a multilayered stratum through transfer matrices. The solution for a random medium has been compared with the solution for the homogeneous medium. The analysis indicates that the stochastic inhomogeneities are likely to increase the damping in a significant way. 相似文献
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This paper deals with the free-field response of the in-plane motion resulting from a combination of inclined incident body waves. The amplification of waves in a viscoelastic layer with stochastic changes in the elastic properties and density is investigated. The method used is that of Karal and Keller and is based on the idea of the fundamental matrix. The third order correlations are neglected. The resulting integro-differential equations for the average displacements are solved by the Laplace transform. Generally, analysis indicates that the stochastic changes in the shear modulus and density enhance the damping in a significant manner. However, increases in the waves' amplification can arise in the case of a small dimensionless frequency and uncorrelated stochastic changes of material parameters. 相似文献
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The paper is concerned with the study of the effect of the randomness of material parameters on mean wave propagation in a semi-infinite viscoelastic medium. The medium considered in this paper is a configuration of a randomly non-homogeneous layer overlying a homogeneous half-space and is loaded harmonically on the top surface. The method used is that of Karal and Keller and is based on the idea of fundamental matrix and Bourret approximation. The integro-differential equation obtained in this paper is solved by the Laplace transform method. By using boundary and continuity conditions the mean wave solution is obtained. Numerical results show that the correlation functions, which introduce long-range interactions, can be the source of the wave amplification. 相似文献
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