Contact resistance among the components of a polymer exchange membrane fuel cell (PEMFC) has a crucial effect on cell performance. The geometry of the endplate plays an essential role in the contact pressure distribution over the membrane electrode assembly (MEA) and the amount of contact resistance between plates. In this work, the effects of endplate geometry on the contact pressure distribut...

We give an exact solution of the 5D Einstein equations which in 4D can be interpreted as a spherically symmetric distribution of matter, whose effective density and pressure are nonstatic, nonuniform, and satisfy the equation of state of radiation. The solution admits a homothetic Killing vector in 5D, which induces the existence of self-similar symmetry in 4D, where the line element as well as...

Although reference values for ambulatory blood pressure (ABP) monitoring have been investigated in several population studies, these values were derived from cross-sectional observations and were based merely on the statistical distribution of blood pressure values. Therefore, we conducted a prospective cohort study to identify reference values for 24-hour ABP in relation to prognosis. We obtai...

 Nowadays, light weight and high strength metals are being used in various industries such as automotive and aerospace. Using aluminum-magnesium alloys is an efficient way to reduce the weight of a specific part. These alloys have poor formability in room temperature thus they should be formed at elevated temperature. Warm hydroforming and hot metal gas forming are conventional methods to form ...

le chatelier's principle is used as a very simple way to predict the effect of a change in conditions on a chemical equilibrium. . however, several studies have reported the violation of this principle, still there is no reported simple mathematical equation to express the exact condition of violation in the gas phase reactions. in this article, we derived a simple equation for the violati...

Although there are a number of papers on how fish swim (Gray, 1957; Aleev, 1969; Lighthill, 1969), we have been unable to find any measurements of the pressure on the body surface measured while a fish is swimming. A preliminary calculation using the Pitot equation indicated that the pressure against the anterior surface of the fish, expressed in centimetres of water, would be approximately equ...

In recent years, pressure-driven analyses of water distribution systems using pressure-flow relationships (PFRs) were shown to be more computationally efficient than those based on flow-pressure (FPRs), such as the widely used Wagner equation and various spline approximations. Using a PFR enhances convergence properties Newton–Raphson method by most network (WDN) solvers. This paper derives new...

The knowledge of plasma pressure is essential for many physics applications in the magnetosphere, such as computing magnetospheric currents and deriving magnetosphere-ionosphere coupling. A thorough knowledge of the 3-D pressure distribution has, however, eluded the community, as most in situ pressure observations are either in the ionosphere or the equatorial region of the magnetosphere. With ...

We consider a reduced dynamics for the first four fluid moments of onedimensional Vlasov-Poisson equation, namely, density, velocity, pressure and heat flux. This depends on an equation state to close system. (closure) connects fifth order moment-related kurtosis in velocity Vlasov distribution-with moments. By solving Jacobi identity, we derive which ensures that resulting model is Hamiltonian...

Photoacoustic tomography is an emerging medical imaging modality based on the reconstruction of an initial internal pressure distribution from surface measurements of photoacoustic wave pulses over time. Current methods used for this image reconstruction assume that the propagation medium is acoustically non-attenuating. However, in soft biological tissue, the frequency dependent ultrasonic att...