The paper concerns the identification process applied for a semi-empirical model of working process in the CI engine. The identification is based on pressure courses in the cylinder recorded during the experimental measurements on the test stand and is performed for estimation of values of the model parameters. Appropriate estimated values of the model parameters ensure minimization of the diff...

In the present work, radiation of sound waves from a coaxial duct is considered. This has an inner wall which infinite and piecewise acoustically absorbent material, while outer semi-infinite rigid. The analytical solution problem found by means Wiener-Hopf technique. Applying Fourier transformation to boundary value problem, explicit expression for scattered field obtained. end, some numerical...

In this paper, a spectral collocation approach based on the rational Chebyshev functions for solving the axisymmetric stagnation point flow on an infinite stationary circular cylinder is suggested. The Navier-Stokes equations which govern the flow, are changed to a boundary value problem with a semi-infinite domain and a third-order nonlinear ordinary differential equation by applying proper si...

While investigating the one-one equivalence between various general combinatorial decision problems, CLEAVE [l] initated the concept of system functions. System functions are defined on natural numbers and their values are finite sets of natural numbers. They have many properties in common with those arising from GodeI numbering various combinatorial systems such as Turing machines, Markov algo...

A convex body K in R has associated with it a unique circumscribed ellipsoid CE(K) with minimum volume, and a unique inscribed ellipsoid IE(K) with maximum volume. We first give a unified, modern exposition of the basic theory of these extremal ellipsoids using the semi–infinite programming approach pioneered by Fritz John in his seminal 1948 paper. We then investigate the automorphism groups o...

We consider a non relativistic particle on the surface of a semi-infinite cylinder of circumference L submitted to a perpendicular magnetic field of strength B and to the potential of impurities of maximal amplitude w. This model is of importance in the context of the integer quantum Hall effect. In the regime of strong magnetic field or weak disorder B >> w it is known that there are chiral ed...

Much structural work on NP-complete sets has exploited SAT's d-self-reduci-bility. In this paper we exploit the additional fact that SAT is a d-cylinder to show that NP-complete sets are p-superterse unless P = NP. In fact, every set that is NP-hard under polynomial-time n o(1)-tt reductions is p-superterse unless P = NP. In particular no p-selective set is NP-hard under polynomial-time n o(1)-...

The problem of a uniform transverse flow past a prolate spheroid of arbitrary aspect ratio a t low Reynolds numbers has been analysed by the method of matched asymptotic expansions. The solution is found to depend on two Reynolds numbers, one based on the semi-minor axis b, Rb = Ublv, and the other on the semi-major axis a, Ra = Ualv (U being the free-stream velocity at infinity, which is perpe...

Cylindrical structures are widely employed in the offshore engineering. How to protect the structures in real sea environment is a vital issue for scientists and engineers. In this paper, the interaction of short-crested waves with a concentric surface-piercing two-cylinder system is studied based on linear wave theory using the scaled boundary finite-element method (SBFEM), a novel semi-analyt...

A new code is presented here, named Gyrokinetic SEmi-LAgragian (GYSELA) code, which solves 4D drift-kinetic equations for ion temperature gradient driven turbulence in a cylinder (r,h,z). The code validation is performed with the slab ITG mode that only depends on the parallel velocity. This code uses a semi-Lagrangian numerical scheme, which exhibits good properties of energy conservation in n...