Propagation of solitons of the Derivative Nonlinear Schrodinger equation in a plasma with fluctuating density

The propagation of quasi-parallel nonlinear small-amplitude magnetohydrodynamic waves in a cold Hall plasma with fluctuating density is studied. The density is assumed to be a homogeneous random function of one spatial variable. The modified Derivative Nonlinear Schrodinger equation (DNLS) is derived with the use of the mean waveform method developed by Gurevich, Jeffrey, and Pelinovsky [Wave Motion 17, 287 (1993)], which is the generalization of the reductive perturbation method for nonlinear waves propagating in random media. This equation differs from the standard DNLS equation by one additional term describing the interaction of nonlinear waves with random density fluctuations. As an example of the use of the modified DNLS equation, the quasi-adiabatic evolution of a one-parametric DNLS soliton propagating through a plasma with fluctuating density is studied

Literature study report of plasticity induced anisotropic damage modeling for forming processes

A literature study report covering the topics; micromechanics of damage, continuum damage mechanics (gurson model and effective variable concept) and the dependence of damage on strain rate and temperature

Bovine papillomavirus: old system, new lessons?

No abstract available

Resonant magnetohydrodynamic waves in high-beta plasmas

When a global magnetohydrodynamic (MHD) wave propagates in a weakly dissipative inhomogeneous plasma, the resonant interaction of this wave with either local Alfven or slow MHD waves is possible. This interaction occurs at the resonant position where the phase velocity of the global wave coincides with the phase velocity of either Alfven or slow MHD waves. As a result of this interaction a dissipative layer embracing the resonant position is formed, its thickness being proportional to R-1/3, where R >> 1 is the Reynolds number. The wave motion in the resonant layer is characterized by large amplitudes and large gradients. The presence of large gradients causes strong dissipation of the global wave even in very weakly dissipative plasmas. Very often the global wave motion is characterized by the presence of both Alfven and slow resonances. In plasmas with small or moderate plasma beta beta, the resonance positions corresponding to the Alfven and slow resonances are well separated, so that the wave motion in the Alfven and slow dissipative layers embracing the Alfven and slow resonant positions, respectively, can be studied separately. However, when beta greater than or similar to R-1/3, the two resonance positions are so close that the two dissipative layers overlap. In this case, instead of two dissipative layers, there is one mixed Alfven-slow dissipative layer. In this paper the wave motion in such a mixed dissipative layer is studied. It is shown that this motion is a linear superposition of two motions, one corresponding to the Alfven and the other to the slow dissipative layer. The jump of normal velocity across the mixed dissipative layer related to the energy dissipation rate is equal to the sum of two jumps, one that occurs across the Alfven dissipative layer and the other across the slow dissipative layer

KB-WOT Quality assurance acoustics: overview and protocols 2008 version

The quality of IMARES' acoustic surveys proved quite unstable in recent years despite extra effort in this field to bring this instability down. The amount of involved scientists in acoustics has been small compared to demersal survey work. Therefore scientific standards of acoustic surveys are relatively low compared resulting in poor standardisation and minimal transparency. Highly specialised technical work made it even more difficult to exchange scientists within IMARES and the quality of acoustic surveys proved to be very sensitive to loss or change in personnel. This situation improved drastically in 2008 when more scientists got involved in acoustic projects and more effort was put in standardisation

On the Machian Origin of Inertia

We examine Sciama's inertia theory: we generalise it, by combining rotation and expansion in one unique model, we find the angular speed of the Universe, and we stress that the theory is zero-total-energy valued. We compare with other theories of the same null energy background. We determine the numerical value of a constant which appears in the Machian inertial force expression devised by Graneau and Graneau[2], by introducing the above angular speed. We point out that this last theory is not restricted to Newtonian physics as those authors stated but is, in fact, compatible with other cosmological and gravitational theories. An argument by Berry[7] is shown in order to "derive" Brans-Dicke relation in the present context.Comment: 10 pages including front one. New version was accepted to publication by Astrophysics and Space Scienc

From the Instrument of Delivery to the Actual Agent of Harm: Fighting the Criminal Purchase of Ammunition

The illegal trade in ammunition in the Netherlands seems to be a small-scale problem. However, as a result of high profits and a small chance of being caught, it is an extremely attractive criminal activity for malicious individuals. The criminal purchase of ammunition is facilitated by weaknesses in the logistic supply chain for legal ammunition, current legislation on the purchase, possession, transport and use of ammunition and the inadequacy with which Dutch government agencies enforce the laws. The fight against the criminal purchase of ammunition could benefit from the adoption of an automated registration system by arms dealers, the use of a different type of freighting method for legal ammunition transport and a common approach by European law enforcement agencies.\u

A General Relativistic Rotating Evolutionary Universe

We show that when we work with coordinate cosmic time, which is not proper time, Robertson-Walker's metric, includes a possible rotational state of the Universe. An exact formula for the angular speed and the temporal metric coefficient, is found.Comment: 5 pages including front cover. Publishe