the narrow operating window between pore pressure and fracture pressure makes drilling difficult in some operations. a feasibility study of managed pressure drilling (mpd) is carried out on iran darquain oil field. the previous wells drilled in this field showed that mud returns were lost during drilling gadvan formation. the present work addresses this problem by means of surface back pressure...

Jajarm Alumina Plant, the only Alumina powder producer in Iran, generates 500,000 tons of red mud annually. The commonest method for final disposal of red mud in Iran is Tailing dam which is neither cost-effective nor environmentally-friendly. The main objective of this study is to evaluate the possibility of red mud recovery to be used for stabilization of loose soils. Red mud samples have bee...

A theory is presented for the mass transport induced by a small-amplitude progressive wave propagating in water over a thin layer of viscoelastic mud modelled as a Voigt medium. Based on a sharp contrast in length scales near the bed, the boundary-layer approximation is applied to the Navier–Stokes equations in Lagrangian form, which are then solved for the first-order oscillatory motions in th...

In this chapter, a heuristic perspective for the multiuser detection problem in the uplink of direct sequence code division multiple access (DS-CDMA) systems is discussed. In particular, the particle swarm optimization multiuser detector (PSO-MuD) is analyzed regarding several figures of merit, such as symbol error rate, near-far and channel error estimation robustness, and computational comple...

Formation temperature is an important parameter in geothermal drilling since it affects drilling fluid, operations and equipment, through mud temperatures. In this study formation temperatures of the five geothermal wells in Germencik-Omerbeyli field were estimated by using mud inlet and outlet temperatures obtained during drilling. GTEMP wellbore thermal simulation model was used to estimate t...

The present paper offers a numerical model which can be applied for the simulation of wave height distribution on a 2-D horizontal soft mud layer. The model is based on mild slope equations and it includes combined wave refraction, diffraction, reflection and breaking. The high energy dissipation of wave height due to the presence of fluid mud layer has also been simulated. Wave height attenuat...

The problem of constructing an adaptive multiuser detector (MUD) is considered for direct sequence code division multiple access (DS-CDMA) signals transmitted through multipath channels. The emerging learning technique, called support vector machines (SVM), is proposed as a method of obtaining a nonlinear MUD from a relatively small training data block. Computer simulation is used to study this...

In uplink block-fading multiple access channel (BFMAC), the advantage of multiuser diversity (MUD) can be taken to achieve higher system throughput. In this letter, with rate constraints for all users and only channel state information available at the receiver assumed, we demonstrate that nonorthogonal multiple access (NOMA) outperforms the counterpart of orthogonal multiple access (OMA) via e...

Earth is one among five elements having an immense impact on human body. It has been adopted as a treatment modality, i.e. mud therapy in naturopathy. It is a simple, cost effective and efficacious treatment used in the treatment of various disorders. Mud is used as a medicine since long as various references are found available in ancient texts indicating its therapeutic uses. Mud has various ...