We consider two variational inequality formulations of the static traac equilibrium problem with xed demand. We determine when an arc-ow formulation can be considered to be equivalent to a path-ow formulation by analyzing the eeect of the form of the travel-time cost function on whether a ow between an origin-destination pair can use all arcs of a directed cycle. An important tool in the analys...

A selection of these reports is available in PostScript form at the Faculty's anonymous ftp-Abstract In this paper some discretization issues that arise in nite volume computations of turbulent ows in arbitrarily shaped domains are presented. Staggered grids are employed. Turbulence is modeled by the standard k-" model. Dis-cretizations are discussed of a general transport equation which are ex...

This note proves noninterference results (NI) for the secrecy analyses for LA and LAM presented in [1], using the inductive information ow analysis. This ow analysis is related to the secrecy typing in [1] in that, while the latter ensures safety of information ow, the former extracts ow of information. The presentation and study of ow analysis is restricted to its use in NI proofs: further stu...

Unmanned aerial vehicle (UAV)-based communication system design has already attracted substantial interest due to UAV flexibility in deployment, cost effectiveness, and in-built line-of-sight air-to-ground channels. However, there is a persistent issue of security threats associated with the broadcast nature UAV: physical layer (PLS) can be introduced enhance secrecy performance that regard. In...

Abstract Landfills will likely remain an essential part of integrated solid waste management systems in many developed and developing countries for the foreseeable future. Further improvements are required to model generated gas from landfills. The literature has not addressed detailed characterization landfill (LFG) modeling by a first-order decay such as LandGEM while using genetic algorithm....

A study of ̄ow visualization and residence time distribution is provided in order to model the ̄ow between two electrodes in a commercial ®lter-press reactor, the ElectroSynCell from Electrocell AB. Flow visualization indicates that both axial and lateral dispersion phenomena occur and a global plug ̄ow behaviour is observed. The ̄ow distribution is asymmetric due to the design of the inlet system ...

Flow on an inclined plane is both one of the most common situations encountered in granular ows, as well as one of the most extensively studied geometries in their theoretical treatment. Nevertheless, so far there are very few systematic studies concerning the innuence of the (dissipative) material properties on the ow. Here, numerical simulations are presented where the focus is on the innuenc...

An internet-based work ̄ow management system (WfMS) enables business participants to work co-operatively at sites belonging to di€erent time zones. Time-related factors have to be incorporated into the traditional work ̄ow processes so as to adapt to the globally distributed applications. This paper proposes a timed work ̄ow process model through incorporating the time constraints, the duration of...

Consider inviscid ‡uids in a channel f 1 < y < 1g. For the Couette ‡ow ~v0 = (y; 0), the vertical velocity of solutions to the linearized Euler equation at ~v0 decays in time. At the nonlinear level, such inviscid damping is widely open. First, we show that in any (vorticity) H s < 3 2 neighborhood of Couette ‡ow, there exist non-parallel steady ‡ows with arbitrary minimal horizontal period. Th...

The coupling of a boundary spin operator to the two dimensional Ising model is known to lead to renormalization group ow to a theory with xed or Dirichlet boundary conditions at large distance from the boundary. Using the fact that spin and disorder operators are dual under a Kramers{Wannier or T-duality transformation, we show that coupling a boundary disorder operator results in an RG ow to f...