Two major issues associated with model validation are addressed here. First, we present a maximum likelihood approach to define and evaluate a model validation metric. The advantage of this approach is it is more easily applied to nonlinear problems than the methods presented earlier by Hills...

In competitive electricity markets, the vertically integrated utilities that were responsible for ensuring system reliability in their own service territories, or groups of territories, often cease to exist. Typically, the burden falls to an independent system operator (ISO) to insure that...

The complexity of water resource issues, its interconnectedness to other systems, and the involvement of competing stakeholders often overwhelm decision-makers and inhibit the creation of clear management strategies. While a range of modeling tools and procedures exist to address these problems,...

The Hudson-Jorgenson Energy/Economic Model - formally known as the Long Term Interindustry Transactions Model (LITM) - is an econometric model of the structure of the US economy. LITM integrates two separate models into one integrated system. These models are the Macroeconomic Model, a growth...

This report describes methods for prioritizing the risk importances of maintenances using a Probabilistic Risk Assessment (PRA). Approaches then are described for quantifying their reliability and risk effects. Two different PRA importance measures, minimal cutset importances and risk reduction...

An analysis of the impact of the political disruption in Iran on the world oil market is presented. During the first quarter of 1979, this disruption caused a loss of approximately 5 million barrels per day (MMBD) of oil production available for export from Iran to the rest of the world. This...

In the absence of age-specific biokinetic models, current retention models of the International Commission on Radiological Protection (ICRP) frequently are used as a point of departure for evaluation of exposures to the general population. These models were designed and intended for estimation...

1991 was continued rapid growth for the Santa Fe Institute (SFI) as it broadened its interdisciplinary research into the organization, evolution and operation of complex systems and sought deeply the principles underlying their dynamic behavior. Research on complex systems--the focus of work at...

Dempster-Shafer theory offers an alternative to traditional probabilistic theory for the mathematical representation of uncertainty. The significant innovation of this framework is that it allows for the allocation of a probability mass to sets or intervals. Dempster-Shafer theory does not...

This report introduces a new perspective on the basic concept of dependent failures where the definition of dependency is based on clustering in failure times of similar components. This perspective has two significant implications: firstly, it relaxes the conventional assumption that dependent...