K e y w o r d s F o u r t h g r a d e fluid, Unsteady flow, Lie symmetries. 1. I N T R O D U C T I O N In recent years, considerable efforts have been usefully devoted to the s tudy of flow of nonNewton ian fluids. This is ma in ly due to their m a n y appl icat ions in pe t ro leum drilling, manufactu r ing of food and paper, and other similar activities. A vast a m o u n t of l i te ra ture i...

This paper examines the diverse nature of user reactions to information technology (IT) within the social-historical context of its organizational use. Employing activity theory as a conceptual framework, we conduct an interpretive analysis of physicians work, perceptions, and IT usage experience at a large community hospital to understand why some of these physicians were favorably disposed to...

Abstract The first step of implanting teeth is to drill a hole in the jaw bone. Excessive temperature produced during drilling is one of the destructive factors for bony tissue. If the temperature generation during surgical drilling exceeds the critical temperature, it could lead to osteonecrosis. This research intends to study drilling parameters such as drilling speed, feed rate, cooling con...

In today’s world, the leading industries are very much concerned about reducing down-time and increasing the productivity as well as the quality. To increase the product quality, the tool should have good performance. Drilling process is widely used in the manufacturing operations in all the manufacturing industries. In this study, two Hidden Markov Models (HMM) such as bar-graph method and the...

Composite material in general, and metal matrix composites in particular, have been a main topic in research for the last 15 years. Metal matrix composites (MMC) have been found to be useful in a number of engineering applications and particle reinforced aluminum MMCs have received considerable attention due to their excellent engineering properties like high strengt h to weight ratio, high tou...

In this paper, after collecting the rock samples from eight mines and one high way slope, the tests for determination of dry density, Uniaxial Compressive Strength, tensile Strength (Brazilian Test), elastic modulus, Schmidt hammer rebound number have been done on samples. In addition, in order to calculating the mean size of rock grains, quartz content, hardness and abrasivity, a thin sections...

this study is focused on investigating the parameters of laser percussion drilling process of nickel-base super alloy inconel 718 with thickness of 1 mm. fiber laser with the power of 500 watts was used as the laser source. laser pulse frequency, duty cycle, laser power, focal point position, were assumed as the laser drilling process variables. the hole geometry features, i.e. entrance hole di...

Simulation technique has been used for a feasibility study of a prospecting project for deep seated ore bodies. The simulation model is divided into three main parts; 1) The bedrock model the mathematical model of the geology in the investigated block.. 2) The ore model the mathematical model of the "economical" targets within the investigated block. 3) The drilling model the mathematical descr...

We present a simplified drift-flux model (DFM) describing a multiphase (gas-liquid) flow during drilling. The DFM uses a specific slip law, without flow-regime predictions, which allows for transition between single and two phase flows. With this model, we design an Unscented Kalman Filter (UKF) for estimation of unmeasured states, production parameters and slip parameters using real time measu...