Global uncertainty

Ikerd J (2008) Family farms in an era of global uncertainty. Prepared for presentation at the 2008 Shivvers Lecture, Iowa State University, Ames, IA, 24 February 2008. Available at http // www.leopold.iastate.edu... 

Local sensitivity analysis is of limited value when the chemical system is non-linear. In this case global methods, which vary the parameters over the range of their possible values, are preferable. Two global uncertainty methods have been used in this work, a screening method, the so-called Morris One-At-A-Time (MOAT) analysis and a Monte Carlo analysis with Latin Hypercube Sampling (Saltelli et al., 2000 Zador et al., submitted, 20041). The analyses were performed by varying rate parameters, branching ratios and constrained concentrations within their uncertainty interval,... 

If public opinion shapes EU policy, then a certain amount of uncertainty surrounds the future of agri-food biotechnology. The lack of equilibrium between the EU and the US adds to the global uncertainty over the issue since both are powerful political and trade powers and have yet to find common ground. This section will interpret the consequences of this uncertainty as the national and industrial responses to changes in their economic interests. 

Gao D., StockweU W. R., and Milford J. B. (1996) Global uncertainty analysis of a regional-scale gas-phase chemical mechanism. J. Geophys. Res. 101, 9071-9078. 

Further statistical analyses can be used to determine the relative influence that any factor or set of factors has on the total variation (global uncertainty). One of these methods is the analysis of variance (ANOVA). This is an important technique for analyzing the effects of categorical factors on a response. However, the assumption of normality of the data has to be checked prior to the use of ANOVA to decompose the variability in the response variable between the different factors. Depending upon the type of analysis, it may be important to determine (a) which factors have a significant effect on the response, and/or (b) how much of the variability in the response variable is attributable to each factor (as described in the statistical software STATGRAPHICS, Vs 5.0). 

Cie , Cie and Cie . The difference between Cj and the reference case is the gas boundary condition the gas pressure is maintained at the atmospheric level at the contact EB-canister for each calculation time. Ci differs from the reference case, because the relative conductivity law is replaced by the constant value of 10 . This value is not realistic, but two reasons have motivated this choice. First, several orders of magnitude uncertainties concern both intrinsic and gas relative conductivity. We have chosen not to discuss intrinsic conductivity concept pertinence, so we have preferred to report the global uncertainties on a single parameter the relative conductivity. Second, if the heat-pipe effect, observed by Pollock (1986), can be activated, the darcean water flux would not govern the saturation kinetics anymore. Taking an exaggerated value is a security to validate our results. In, both... 

Since the first Cesium-atomic clock based on an atomic beam, different approaches have been developed, justified by the need to reduce the global uncertainty of the system. The search for an appropriate atomic transition is guided by seeking its potentiality to have the narrowest spectral transition possible. Atomic calculations have assisted in making this choice. At the beginning of the atomic time era. 

In order to apply global uncertainty and sensitivity analysis, we must assume that the parameters of the models can be changed throughout a domain of the parameter space rather than just a small region close to the nominal values. In the simplest case, a range of possible values is assigned to each parameter... 

The general task of global uncertainty analysis is to determine the joint pdf of the simulation results knowing the joint pdf of the model parameters. The role of global... 

Global Uncertainty Analysis Using Sampling-Based Methods... 

Handling Correlated Inputs Within Global Uncertainty and Sensitivity Studies... 

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