In this paper we discuss the treatment of discontinuities in Smoothed Particle Hydrodynamics (SPH) simulations. In particular we discuss the difference between integral and differential representations of the fluid equations in an SPH context and how this relates to the formulation of dissipative terms for the capture of shocks and other discontinuities. This has important implications for many...

This paper presents a discussion on the properties of collocation meshfree method, Updated Lagrangian Taylor-SPH (UL-TSPH), for dynamic problems in solid mechanics. The PDEs are written mixed form terms stress and velocity elastodynamics problems. Two sets particles used to discretize partial differential equations, resulting avoiding tensile instability inherent classical SPH formulations. Num...

  Background: Health status is an individual’s relative level of wellness and illness. Self-Perceived Health (SPH) is a single item considered as a health indicator for national and international survey. The aim of this study was to evaluate the SPH measure and its determinants in a National sample of Iranian children and adolescents.   Materials and Methods:  This National study was performed...

Further development and additional details and tests of Adaptive Smoothed Particle Hydrodynamics (ASPH), the new version of Smoothed Particle Hydrodynamics (SPH) described in Shapiro et al. (1996; Paper I) are presented. The ASPH method replaces the isotropic smoothing algorithm of standard SPH, in which interpolation is performed with spherical kernels of radius given by a scalar smoothing len...

We calculate numerically the probability exp[ 1 λ F (E/E sph , N/N sph)] of the false vacuum decay in the massive four-dimensional −λφ 4 model from multipar-ticle initial states with fixed number of particles N and energy E greater than the height of the barrier E sph. We find that at E ∼ < 3E sph and N ∼ < 0.4N sph the decay is classically forbidden and thus is exponentially suppressed. We arg...

This paper presents a survey of Smoothed Particle Hydrodynamics (SPH) and its use in computational fluid dynamics. As a truly mesh-free particle method based upon the Lagrangian formulation, SPH has been applied to a variety of different areas in science, computer graphics and engineering. It has been established as a popular technique for fluid based simulations, and has been extended to succe...

A new Chemo – Dynamical Smoothed Particle Hydrodynamic (CD – SPH) code is presented. The disk galaxy is described as a multi – fragmented gas and star system, embedded into the cold dark matter halo. The star formation (SF) process, SNII, SNIa and PN events as well as chemical enrichment of gas have been considered within the framework of standard SPH model. Using this model we try to describe ...

Activation of the PDGF receptor on human arterial smooth muscle cells (SMC) induces migration and proliferation via separable signal transduction pathways. Sphingosine-1-phosphate (Sph-1-P) can be formed following PDGF receptor activation and therefore may be implicated in PDGF-receptor signal transduction. Here we show that Sph-1-P does not significantly affect PDGF-induced DNA synthesis, prol...

Sphingosine (Sph) has been implicated as a modulator of membrane signal transduction systems and as a regulatory element of cardiac and skeletal muscle physiology, but little information is presently available on its precise mechanism of action. Recent studies have shown that sphingosine 1-phosphate (S1P), generated by the action of sphingosine kinase (SphK) on Sph, also possesses biological ac...

OBJECTIVES We assessed the characteristics of self-perception of health (SPH) in relation to psychological distress and physical symptoms, and willingness of servicemen to see their Medical Officer (MO) by their SPH rating. DESIGN We randomly selected 4,500 servicemen to receive either a full or an abridged screening questionnaire. MEASURES The full questionnaire included 6 items from the s...