Detection of subsurface structures by means of gravity method can be used to determine mass distribution and density contrast of rock units. This distribution could be detected by different geophysical methods, especially gravity method. However, gravity techniques have some drawbacks and can't be always successful in distinguishing subsurface structures. Performance of the gravity technique co...

asymptotically exact and nonlocal fourth order nonlinear evolution equations are derived for two coupled fourth order nonlinear evolution equations have been derived in deep water for two capillary-gravity wave packets propagating in the same direction in the presence of wind flowing over water.we have used a general method, based on zakharov integral equation.on the basis of these evolution eq...

BACKGROUND The problems of patients with erectile dysfunction have been recognized, leading to the emergence of sildenafil, which has led to successful treatment in many cases. The purpose of this study is to examine the effect of sildenafil on the pulse wave velocity of patients with erectile dysfunction. METHODS Fifteen patients with erectile dysfunction were enrolled for this study. The br...

optimization of reservoir parameters is an important issue in petroleum exploration and production. the ant colony optimization(aco) is a recent approach to solve discrete and continuous optimization problems. in this paper, the ant colony optimization is usedas an intelligent tool to estimate reservoir rock properties. the methodology is illustrated by using a case study on shear wave velocity...

It is well known that the wave propagation depends mainly on its velocity and frequency in one direction for a single wave[1-3]. There are many literatures devoted researches of single wave propagation such as solitary wave, periodic wave, chirped wave, rational wave etc [4-6]. However, what can be happen when two and even more waves with different features propagate together along different di...

This paper studies the propagation of shear waves in a composite structure consisting of a piezoelectric layer perfectly bonded over a micropolar elastic half space. The general dispersion equations for the existence of shear waves are obtained analytically in the closed form. Some particular cases have been discussed and in one special case the relation obtained is in agreement with existing r...

background: the aim of this study was to echocardiographically assess the effects of eecp (enhanced external counterpulsation therapy) therapy on systolic and diastolic cardiac function. methods: lvef (left ventricular ejection fraction), esv (end-systolic volume), edv (end-diastolic volume), sm (myocardial systolic wave) , ea (myocardial early diastolic wave), vp (propagation velocity), e/ea (...

The indispensable vital structure in any harbor is a breakwater in order to make available calm water region inshore. Pile breakwater can be employed as a small coastal protection structure where tranquility required is low. This study is concerned with CFD study on the performance of perforated hollow pile to dissipate wave energy and the novelty of this investigation is the role of perforatio...

This study considers pricing, production and transportation decisions in a Stackelberg game between three-stage, multi-product, multi-source and single-period supply chains called leader and follower. These chains consist of; manufacturers, distribution centers (DCs) and retailers. Competition type is horizontal and SC vs. SC. The retailers in two chains try to maximize their profit through pri...