Sharif Digital Repository

In this paper, nano/microstructured-conducting polypyrrole has been prepared on Cu/Au interdigital electrode surfaces by using constant potential amperometry technique. The Fe(II) ions were used as catalyst and X = ClO4 -, pTs-, Cl-, TCA-, DS-, DBS- was implemented as anion dopants. The morphologies of the films were investigated by field emission scanning electron microscope. A remarkable dependence was observed between the type of anion dopant and the morphology of polypyrrole (PPy). The sensing behavior of the PPy-X sensor has been studied toward acetone, methanol, ethanol, 1-propanol, 2-propanol, nitromethane, propylamine, pyridine, and gas mixtures of aliphatic alcohols. The responses... 

Accurate estimation of the reservoir parameters is crucial to predict the future reservoir behavior. Well testing is a dynamic method used to estimate the petro-physical reservoir parameters through imposing a rate disturbance at the wellhead and recording the pressure data in the wellbore. However, an accurate estimation of the reservoir parameters from well-test data is vulnerable to the noise at the recorded data, the non-uniqueness of the obtained match, and the accuracy of the optimization algorithm. Different stochastic optimization methods have been applied to this address problem in the literature. In this study, we apply the recently developed iterative ensemble Kalman filter in the... 

Filtrate and solid invasion from drilling fluids are two key sources of formation damage, and can result in formation permeability impairment. Typically, spurt invasion of mud solids causes the evolution of an external mud cake which tends to reduce further solids and filtrate influx. However, uncontrolled spurt and filtrate invasion are detrimental because they reduce the permeability of the formation. Mud composition, formation rock's permeability and porosity, and temperature can influence both spurt and filtrate invasion. The sizes of mud solids relative to the average pore size of a rock are also important in predicting the extent of mud invasion and permeability impairment. In this... 

Accurate estimation of the reservoir parameters is crucial to predict the future reservoir behavior. Well testing is a dynamic method used to estimate the petro-physical reservoir parameters through imposing a rate disturbance at the wellhead and recording the pressure data in the wellbore. However, an accurate estimation of the reservoir parameters from well-test data is vulnerable to the noise at the recorded data, the non-uniqueness of the obtained match, and the accuracy of the optimization algorithm. Different stochastic optimization methods have been applied to this address problem in the literature. In this study, we apply the recently developed iterative ensemble Kalman filter in the... 

Spinal posture including thorax/pelvis orientations as well as loads on the intervertebral discs are crucial parameters in biomechanical models and ergonomics to evaluate the risk of low back injury. In vivo measurement of spinal posture toward estimation of spine loads requires the common motion capture techniques and laboratory instruments that are costly and time-consuming. Hence, a closed loop algorithm including an artificial neural network (ANN) and fuzzy logic is proposed here to predict the L5–S1 segment loads and thorax/pelvis orientations in various 3D reaching activities. Two parts namely a fuzzy logic strategy and an ANN from this algorithm; the former, developed based on the...