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Exploring parameter sensitivities of the land surface using a locally coupled land-atmosphere model
This paper presents a multicriteria analysis that explores the sensitivity of the land surface to changes in both land and atmospheric parameters, in terms of reproducing surface heat fluxes and ground temperature; for the land parameters, offline sensitivity analyses were also conducted for comparison to infer the influence of land-atmosphere interactions. A simple "one-at-a-time" sensitivity analysis was conducted first to filter out some insensitive parameters, followed by a multicriteria sensitivity analysis using the multiobjective generalized sensitivity analysis algorithm. The models used were the locally coupled National Center for Atmospheric Research (NCAR) single-column community climate model and the offline NCAR land surface model, driven and evaluated by a summer intensive operational periods (IOP) data set from the southern Great Plains. As expected, the results show that land-atmosphere interactions (with or without land-atmosphere parameter interactions) can have significant influences on the sensitivity of the land surface to changes in the land parameters, and the single-criterion sensitivities can be significantly different from the multicriteria sensitivity. These findings are mostly model and data independent and can be generally useful, regardless of the model/data dependence of the sensitivities of individual parameters. The exceptionally high sensitivities of the selected atmospheric parameters in a multicriteria sense (and in particular for latent heat) appeal for adequate attention to the specification of effective values of these parameters in an atmospheric model. Overall, this study proposes an effective framework of multicriteria sensitivity analysis beneficial to future studies in the development and parameter estimation of other complex (offline or coupled) land surface models. Copyright 2004 by the American Geophysical Union
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Binding site transitions across strained oxygenated and hydroxylated Pt(111)
The effects of strain σ on the binding position preference of oxygen atoms and hydroxyl groups adsorbed on Pt(111) have been investigated using density functional theory. A transition between the bridge and FCC binding occurs under compressive strain of the O/Pt(111) surface. A significant reconstruction occurs under compressive strain of the OH/Pt(111) surface, and the surface OH groups preferentially occupy on-top (bridge) positions at highly compressive (less compressive/tensile) strains. Changes to magnetisation of the O- and OH-populated surfaces are discussed and for O/Pt(111) oxygenation reduces the surface magnetism via a delocalised mechanism. The origins of the surface magnetisation for both O- and OH-bearing systems are discussed in terms of the state-resolved electronic populations and of the surface charge density
Strain engineering of the CeNi5 system
The effect of strain on the CeNi5 system has been investigated using density functional theory (DFT). The studies have shown that localised Ce 4f and Ni 3d states carry the magnetic moment of the material. The Ce 4f moment remains relatively unchanged during strain whereas the Ni 3d moment increases as the strain becomes increasingly tensile in both the basal and non-basal directions. A significant strain-dependent interaction exists between delocalised, non-magnetic Ce 6s–Ni 4s states. A weaker group of Ni 3d–Ce 6s/Ni 4s and Ni 3d–Ni 3d interactions exist, indicating that competing localised and delocalised mechanisms act on the Ni 3d states during strain
Parameter estimation of a land surface scheme using multicriteria methods
Attempts to create models of surface-atmosphere interactions with greater physical realism have resulted in land surface schemes (LSS) with large numbers of parameters. The hope has been that these parameters can be assigned typical values by inspecting the literature. The potential for using the various observational data sets that are now available to extract plot-scale estimates for the parameters of a complex LSS via advanced parameter estimation methods developed for hydrological models is explored in this paper. Results are reported for two case studies using data sets of typical quality but very different location and climatological regime (ARM-CART and Tucson). The traditional single-criterion methods were found to be of limited value. However, a multicriteria approach was found to be effective in constraining the parameter estimates into physically plausible ranges when observations on at least one appropriate heat flux and one properly selected state variable are available. Copyright 1999 by the American Geophysical Union
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Parameter sensitivity analysis for different complexity land surface models using multicriteria methods
A multicriteria algorithm, the MultiObjective Generalized Sensitivity Analysis (MOGSA), was used to investigate the parameter sensitivity of five different land surface models with increasing levels of complexity in the physical representation of the vegetation (BUCKET, CHASM, BATS 1, Noah, and BATS 2) at five different sites representing crop land/ pasture, grassland, rain forest, cropland, and semidesert areas. The methodology allows for the inclusion of parameter interaction and does not require assumptions of independence between parameters, while at the same time allowing for the ranking of several single-criterion and a global multicriteria sensitivity indices. The analysis required on the order of 50 thousand model runs. The results confirm that parameters with similar "physical meaning" across different model structures behave in different ways depending on the model and the locations. It is also shown that after a certain level an increase in model structure complexity does not necessarily lead to better parameter identifiability, i.e., higher sensitivity, and that a certain level of overparameterization is observed. For the case of the BATS 1 and BATS 2 models, with essentially the same model structure but a more sophisticated vegetation model, paradoxically, the effect on parameter sensitivity is mainly reflected in the sensitivity of the soil-related parameter. Copyright 2006 by the American Geophysical Union
Sensitivity analysis of a land surface scheme using multicriteria methods
Attempts to model surface-atmosphere interactions with greater physical realism have resulted in complex land surface schemes (LSS) with large numbers of parameters. A companion paper describes a multicriteria calibration procedure for extracting plot-scale estimates of the preferred ranges of these parameters from the various observational data sets that are now available. A complementary procedure is presented in this paper that provides an objective determination of the multicriteria sensitivity of the modeled variables to the parameters, thereby allowing the number of calibration parameters and hence the computational effort to be reduced. Two case studies are reported for the BATS model using data sets of typical quality but very different location and climatological regime (ARM-CART and Tucson). The sensitivity results were found to be consistent with the physical properties of the different environments, thereby supporting the reasonableness of the model formulation. Further, when the insensitive parameters are omitted from the calibration process, there is little degradation in the quality of the model description and little change in the preferred range of the remaining parameters. Copyright 1999 by the American Geophysical Union
Translation studies and metaphor studies: Possible paths of interaction between two well-established disciplines
The objects of study of these two disciplines are etymological cognates, the meaning that lies
at the heart of both translation and metaphor being that of transfer. The study of metaphor in
translation therefore involves tackling the complexities of a double act of transfer through the
use of methodologies that are correspondingly subtle.
The article aims to investigate what the disciplines of translation studies and metaphor studies
have in common and what the potential for interdisciplinary research might be. As argued by
Israel (2011), having absorbed numerous research models and approaches from other
disciplines over the last few decades, translation studies is in a strong position to share its
insights and perspectives with these same disciplines. In the case of research into metaphor in
translation, although the centres of gravity of translation studies and metaphor studies are rather
different there is great potential for a two-way interaction between these two disciplines. On
the one hand, it is now virtually inconceivable that a study of metaphor in translation should
not take full account of work by scholars specialising in metaphor studies. On the other hand,
translation studies can provide metaphor scholars with mono-, bi- and even multilingual data
from its case studies to supplement their own descriptive work. There do of course exist a
number of caveats regarding the compatibility of material from the two disciplines. However,
in many cases the result of such research has been work worthy of the attention of scholars
working within both disciplines. The article focuses specifically on text-based research but is
of relevance to other approaches as well
Is 35 U.S.C. § 271(F) Keeping Pace With The Times?: The Law After the Federal Circuit’s Cardiac Pacemakers Decision
In a common business arrangement, an American software company designs software in the United States, then sends the software code abroad where copies are mass-produced and distributed. Prior to the Federal Circuit’s ruling in Cardiac Pacemakers, Inc. v. St. Jude Medical, Inc., the American company could have been found liable for patent infringement under Section 271(f) of the Patent Act if the software mass-produced abroad infringed a United States patent.Cardiac Pacemakers, however, leaves United States patent owners defenseless when the allegedly infringed patent claims are method claims. The background of Cardiac Pacemakers, the Court’s rationales, and the implications of the decision are the subject of this Note
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