42,188 research outputs found
The application of remote sensing techniques: Technical and methodological issues
Capabilities and limitations of modern imaging electromagnetic sensor systems are outlined, and the products of such systems are compared with those of the traditional aerial photographic system. Focus is given to the interface between the rapidly developing remote sensing technology and the information needs of operational agencies, and communication gaps are shown to retard early adoption of the technology by these agencies. An assessment is made of the current status of imaging remote sensors and their potential for the future. Public sources of remote sensor data and several cost comparisons are included
A Skylab program for the International Hydrological Decade (IHD)
There are no author-identified significant results in this report
How the Liquid-Liquid Transition Affects Hydrophobic Hydration in Deeply Supercooled Water
We determine the phase diagram of liquid supercooled water by extensive
computer simulations using the TIP5P-E model [J. Chem. Phys. {\bf 120}, 6085
(2004)]. We find that the transformation of water into a low density liquid in
the supercooled range strongly enhances the solubility of hydrophobic
particles. The transformation of water into a tetrahedrally structured liquid
is accompanied by a minimum in the hydration entropy and enthalpy. The
corresponding change in sign of the solvation heat capacity indicates a loss of
one characteristic signature of hydrophobic hydration. The observed behavior is
found to be qualitatively in accordance with the predictions of the information
theory model of Garde et al. [Phys. Rev. Lett. {\bf 77}, 4966 (1996)].Comment: 4 pages, 4 figures, twocolumn Revtex, modified text applied changes
to figure 1, 2d, 3,
Comparison of the RAINS Emission Control Cost Curves for Air Pollutants with Emission Control Costs Computed by the GAINS Model
This paper compares cost curves of SO2, NOx and PM2.5 emission controls generated with the RAINS (Regional Air Pollution Information and Simulation) model with cost estimates obtained from the GAINS (Greenhouse Gas - Air Pollution Interactions and Synergies) model. Based on the same set of input data, results from both models are very similar, and differences are considered as insignificant
An adaptive Strategy for the Multi-scale Analysis of Plate and Shell Structures with Elasto-plastic Material Behaviour
Modelling of structures on different scales has been a popular subject in the past. Within such a strategy the structural behaviour is modeled on a macro-level, describing the structure itself, whereas the material behaviour is modeled on a micro-level. Here typically RVEs are used. The proper choice of boundary conditions for the RVE is a difficult task in case of shell structures. It should be mentioned that the correct calculation of material parameters on the macro level is crucial for any associated nonlinear analysis. Here, results have been presented for homogeneous and layered structures for composite materials in Gruttmann and Wagner (2013). In the present paper we will discuss the influence of material nonlinear behaviour, here the elasto-plastic behaviour, within the above described setting. Typically these calculations are very time consuming, even if the FE-model is parallelized. Thus we will discuss possibilities to change material models on the structural model during the loading process, starting with elastic material models without a second scale and switching to a two-scale approach, where necessary
An advanced shell model for the analysis of geometrical and material nonlinear shells
In this paper layered shells subjected to static loading are considered. The displacements of the Reissner–Mindlin theory are enriched by a an additional part. These so-called fluctuation displacements include warping displacements and thickness changes. They lead to additional terms for the material deformation gradient and the Green–Lagrangian strain tensor. Within a nonlinear multi-field variational formulation the weak form of the boundary value problem accounts for the equilibrium of stress resultants and couple resultants, the local equilibrium of stresses, the geometrical field equations and the constitutive equations. For the independent shell strains an ansatz with quadratic shape functions is chosen. This leads to a significant improved convergence behaviour especially for distorted meshes. Elimination of a set of parameters on element level by static condensation yields an element stiffness matrix and residual vector of a quadrilateral shell element with the usual 5 or 6 nodal degrees of freedom. The developed model yields the complicated three-dimensional stress state in layered shells for elasticity and elasto-plasticity considering geometrical nonlinearity. In comparison with fully 3D solutions present 2D shell model requires only a fractional amount of computing time
An ERTS-1 investigation for Lake Ontario and its basin
The author has identified the following significant results. Methods of manual, semi-automatic, and automatic (computer) data processing were evaluated, as were the requirements for spatial physiographic and limnological information. The coupling of specially processed ERTS data with simulation models of the watershed precipitation/runoff process provides potential for water resources management. Optimal and full use of the data requires a mix of data processing and analysis techniques, including single band editing, two band ratios, and multiband combinations. A combination of maximum likelihood ratio and near-IR/red band ratio processing was found to be particularly useful
New order parameters in the Potts model on a Cayley tree
For the state Potts model new order parameters projecting on a group of
spins instead of a single spin are introduced. On a Cayley tree this allows the
physical interpretation of the Potts model at noninteger values q of the number
of states. The model can be solved recursively. This recursion exhibits chaotic
behaviour changing qualitatively at critical values of . Using an
additional order parameter belonging to a group of zero extrapolated size the
additional ordering is related to a percolation problem. This percolation
distinguishes different phases and explains the critical indices of percolation
class occuring at the Peierls temperature.Comment: 16 pages TeX, 5 figures PostScrip
Epitaxial growth of deposited amorphous layer by laser annealing
We demonstrate that a single short pulse of laser irradiation of appropriate energy is capable of recrystallizing in open air an amorphous Si layer deposited on a (100) single-crystal substrate into an epitaxial layer. The laser pulse annealing technique is shown to overcome the interfacial oxide obstacle which usually leads to polycrystalline formation in normal thermal annealing
Radiation from a charged particle-in-flight from a laminated medium to vacuum
The radiation from a charged particle-in-flight from a semi-infinite
laminated medium to vacuum and back,- from vacuum to the laminated medium, has
been investigated. Expressions for the spectral-angular distribution of
radiation energy in vacuum (at large distances from the boundary of laminated
medium) were obtained for both the cases with no limitations on the amplitude
and variation profile of the laminated medium permittivity. The results of
appropriate numerical calculations are presented and possible applications of
the obtained results are discussed.Comment: 8 pages, 6 figures, contribution to Proceedings of International
Symposium RREPS-2009, 07-11 September, 2009, Zvenigorod, Russi
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