In this paper, we study the Payne-Whitham (PW) model as a hyperbolic system of conservation laws with relaxation. After studying the Riemann problem for the homogeneous version of the PW model, we introduce three first-order numerical solution methods for solving the system. In these methods, the homogeneous part of the PW model is approximated by Godunovtype difference equations, and different...

−The vapor-phase MTBE decomposition was examined in a shell and tube-type catalytic membrane reactor (CMR). 12-Tungstophosphoric acid (PW) was used as a catalyst and poly-2,6-dimethyl-1,4-phenylene oxide (PPO) was used as a polymer material. A single-phase CMR (PW-PPO/Al2O3, type-1) and a composite CMR (PW-PPO/ PPO/Al2O3, type-2) were successfully designed and characterized. It was revealed tha...

[1] In this paper, the atmospheric precipitable water (PW) was estimated by means of Advanced Very High Resolution Radiometer (AVHRR) thermal channels brightness temperature difference (DT), over the broader area of Greece. The AVHRR derived DT was calculated in a grid of 5 5 km cells; the corresponding PW value in each grid cell was extracted from Moderate Resolution Imaging Spectroradiometer ...

Let Pw be the lattice of Muchnik degrees of nonempty Π1 subsets of 2. The lattice Pw has been studied extensively in previous publications. In this note we prove that the lattice Pw is not Brouwerian.

Background: It was intended to investigate the effect of physical wedge (PW) and enhanced dynamic wedges (EDW) on contralateral breast dose during primary breast irradiation in radiotherapy treatment, using high energy photon beams. Materials and Methods: The Varian’s Clinac dual mode linear accelerator model 2100 C/D and Siemen’s Primus accelerators were used for radiation doses wi...

Let P be a set of reals viewed as a mass problem, i.e., a “decision problem with more than one solution.” Here the “solutions” of P are the elements of P . Many unsolvable mathematical problems are best viewed as mass problems. One says that a mass problem P is weakly reducible to a mass problem Q if for every solution Y of Q there exists a solution X of P such that X is Turing reducible to Y ....

The two heteropolyacids H(3)PW(12)O(40) and H(3)PMo(12)O(40), and their homologous salts (NH(4))(3)PW(12)O(40), and (NH(4))(3)PMo(12)O(40) were prepared and tested in the cationic polymerization of styrene. The results showed that the heteropolytungstates were more reactive than the heteropolymolybdates. It has been found that the yield and the viscosity average molecular weight (M(v)) of polys...

OBJECTIVES This study investigated: (1) the association of physical workload (PW) and risk of rheumatoid arthritis (RA); (2) the potential interactions between PW and the genes in the human leucocyte antigen (HLA) region. METHODS A population-based case-control study involving incident cases of RA (3150 cases and 5130 controls) was performed using data from the Swedish Epidemiological Investi...

Broca's area is classically associated with speech production. Recently, Broca's area has also been implicated in speech perception and non-linguistic information processing. With respect to the latter function, Broca's area is considered to be a central area in a network constituting the human mirror system, which maps observed or heard actions onto motor programs to execute analogous actions....