For a class of positive matrices A+K with a stable positive nominal part A and a structured positive perturbation part K , we address the problem of finding the largest set of admissible perturbations such that the global matrix remains stable. Theoretical bounds are derived and an algorithm for constructing this set is presented. As an example, this algorithm is applied to the regulation of wa...

In this paper we study nite volume element approximations for two dimensional parabolic integro di erential equations arising in modeling of nonlocal reactive ows in porous media These type of ows are also called NonFickian ows with mixing length growth For simplicity we only consider linear nite volume element methods although higher order volume elements can be considered as well under this f...

Numerical investigation of compressible flows in constant area ducts becomes substantially complicated when the surface roughness and heat flux conditions simultaneously act as independent and considerable boundary conditions that create significant influences on the flow and heat transfer characteristics. This article presents GAS-DYN v2.0, a specialized software package, capable of handling n...

We propose a volume fraction based approach to effectively simulate the miscible and immiscible flows simultaneously. In this method, a volume fraction is introduced for each fluid component and the mutual interactions between different fluids are simulated by tracking the evolution of the volume fractions. Different techniques are employed to handle the miscible and immiscible interactions and...

It is common practice to have Websites interact with consumers by delivering personalized services, among which content relevance is most widely adopted on Internet advertising. However, little is known about the impact of relevance on consumers’ psychological states and the underlying mechanism of relationship between relevance and attitude toward Websites. Building upon flow theory and Hoffma...

Appraisal of the concept of energy rate density continues, as both a potential quantitative metric for complexity studies and a key feature of a unifying hypothesis for the origin and evolution of material systems throughout Nature writ large. This article extends a recent study reported in this journal, hereby analyzing normalized energy flows for an array of complex systems experiencing physi...

We investigate the complexity and approximability of network ow improvement problems. In these problems, one incurs costs for increasing the capacity of an edge, while the goal is to achieve a ow of maximum value through the network. We study several improvement strategies. Furthermore, we investigate the relationship of network ow improvement problems to network xed cost ow problems, where one...

A maximum flow over time generalizes standard maximum flow by introducing a time component. The object is to send as much flow from source to sink in T time units as possible, where capacities are interpreted as an upper bound on the rate of flow entering an arc. A related problem is the universally maximum flow, which is to send a flow from source to sink that maximizes the amount of flow arri...

The Sleepers River Research Watershed (SRRW) in Vermont, USA, has been the site of active hydrologic research since 1959 and was the setting where Dunne and Black demonstrated the importance and controls of saturation-excess overland flow (SOF) on streamflow generation. Here, we review the early studies from the SRRW and show how they guided our conceptual approach to hydrologic research at the...

Control charts are extensively used in processes and are very helpful in determining the special cause variations so that a timely action may be taken to eliminate them. One of the charting procedures is the Shewhart-type control charts, which are used mainly to detect large shifts. Two alternatives to the Shewhart-type control charts are the cumulative (CUSUM) control charts and the exponentia...