Modern diesel fuel injection system (common rail and pump-nozzle-units) requires the reference of crank angles, engine speed and load to estimate the two parameters: crank angle at the start of fuel injection and amount of fuel to inject for a diesel engine. Measurement of engine speed of a combustion engine is carried out by sensor wheels mounted on the crankshaft. Crank angles can be estimate...

This work concerns the mathematical modeling and computer simulations of the heat transfer process. The core is solving the time-dependent partial differential equation of parabolic type. Instead of a uniform discretization of the considered time interval, an adaptive time-stepping procedure is applied in an effort to decrease the simulation time. The procedure is based on the local comparison ...

Radio-frequency ablation is a low invasive technique for treatment of liver tumors. This work concerns the mathematical modeling and computer simulation of the heat transfer process. The core is solving the time-dependent partial differential equation of parabolic type. Instead of a uniform discretization of the considered time interval, an adaptive time-stepping procedure is applied in an effo...

Using the abstract framework of [10] we analyze a residual a posteriori error estimator for space-time finite element discretizations of parabolic pdes. The estimator gives global upper and local lower bounds on the error of the numerical solution. The finite element discretizations in particular cover the so-called θ-scheme, which includes the implicit and explicit Euler methods and the Crank-...

An interpolation based non-conforming spectral element atmospheric model is described. The error norms for a standard test problem are compared against uniform resolution results. Preliminary results for an adaptive mesh refinement strategy are reported. To avoid local time-stepping, a nonlinear variant of operator integration factor splitting has been implemented. A backward differentiation fo...

Boundary value methods are applied to find transient solutions of M/M/2 queueing systems with two heterogeneous servers under a variant vacation policy. An iterative method is employed to solve the resulting large linear system and a Crank-Nicolson preconditioner is used to accelerate the convergence. Numerical results are presented to demonstrate the efficiency of the proposed method.

Nowadays, due to the increasing power of diesel engines, especially heavy duty diesel engines, and increasing gas pressure inside the combustion chamber, the forces acting on the engine bearings have dramatically raised. On the other hand, becaus eof the competition in the market, it is necessary to increase the engine bearing life and reduce its failure as much as possible. The engine bearings...

Human movements are physical processes combining the classical mechanics of the human body moving in space and the biomechanics of the muscles generating the forces acting on the body under sophisticated sensory-motor control. The characterization of the performance of human movements is a problem with important applications in clinical and sports research. One way to characterize movement perf...