Markovian queueing networks may be modeled by generalized stochastic Petri nets. The simulation of a model in a properly chosen simulator provides information on the performances of the actual system, mainly in case that the analytical study is intricate. After presenting some general notions on queueing networks and on generalized stochastic Petri nets, this paper points out the PN Toolbox for...

PURPOSE Easy particle propagation (Epp) is a user code for the EGSnrc code package based on the c+ + class library egspp. A main feature of egspp (and Epp) is the ability to use analytical objects to construct simulation geometries. The authors developed Epp to facilitate the simulation of x-ray imaging geometries, especially in the case of scatter studies. While direct use of egspp requires kn...

An analytical approach is presented to achieve the fast design of high-power waveguide windows. The analytical calculation is compared with the result of numerical simulation via the finite-element code high frequency structure simulator and the experiments of W-band waveguide windows performed at the Stanford Linear Accelerator Center (SLAC), Stanford University, Stanford, CA. The closed form ...

BioSim is a simulation tool which captures many basic life support functions in an integrated simulation. Conventional analyses can not efficiently consider all possible life support system configurations. Heuristic approaches are a possible alternative. In an effort to demonstrate efficacy, a validating experiment is designed to compare the configurational optima discovered by heuristic approa...

one of the great challenges in the processing of materials using equal channel angular pressing (ecap) is the high forming forces required to produce large shear deformation in the material. researchers show that the friction forces between the die and the sample constitute a great part of the total forming forces. recently, ultrasonic vibrations are successfully implemented into the ecap proce...

Two problems in the self-consistent, electrothermal co-simulation of nanoscale devices, are discussed. It is shown that the construction of dynamic compact thermal models for nanoscale devices, based on solution of the hyperbolic (wavelike) heat transport equation, can follow essentially the same approach as the authors’ analytical thermal impedance matrix method for the parabolic (diffusive) e...

This study aims to investigate the penetration of a projectile into a surrogate human tissue numerically, using Finite Element (FE) simulation. 20% Balistic Gelatin material (BG) is simulated with an elasto-plastic hydrodynamic constitutive law, and then impacted by steel spheres at different velocities. The results from the FE simulations are compared with existing experimental data and other ...

In this paper, the performance of the emerging Switched Bunch Of Disks (SBOD) RAID architecture is compared to the more traditional Managed Bunch Of Disks (MBOD) using both analytical and simulation models. The benchmark used for this comparison is the conventional IOmeter that enables Throughput and IOPS of these systems to be compared. The SBOD configuration that maximises its performance is ...

Performance of multistage interference cancellation (MIC) and three combining techniques, i.e., multipath decorrelating (MIC-DECO), optimum combining (MIC-OPTM), and Rake combining (MIC-RAKE) for asynchronous QPSK/ DS/CDMA over frequency-selective multipath Rayleigh fading channels is studied. The analytical bit error probabilities of the MIC-DECO and MIC-OPTM are derived and shown to be in a g...

Reliability assessment and risk analysis of machine rotors in various overload and malfunction situations present challenge to engineers and operators. In this paper a new analytical method for evaluation of rotor under large deformation is addressed. Model is presented in general form to include also composite rotors. Presented simulation procedure is based on variational work method and has c...