Abstract: The governing equations of motion for a drill string considering coupling between axial, lateral and torsional vibrations are obtained using a Lagrangian approach. The result leads to a set of non-linear equations with time varying coefficients. A fully coupled model for axial, lateral, and torsional vibrations of drill strings is presented. The bit/formation interactions are assumed ...

A significant increase in spectrum efficiency is required to cope with the exponentially increasing traffic loads. These challenges the design of multipleinput multiple-output (MIMO) systems associated with the BS (Base Station). A typical long-term evolution BS consists of radio-frequency (RF) chains, direct current to direct current converters, cooling fans, etc. An adaptive antenna selection...

In this paper, we have implemented and designed a sorting network for reversible logic circuits synthesis in terms of n*n Toffoli gates. The algorithm presented in this paper constructs a Toffoli Network based on swapping bit strings. Reduction rules are then applied by simple template matching and removing useless gates from the network. Random selection of bit strings and reduction of control...

There are many mode decisions in the video coding process that are used to optimize the performance in terms of the bit rate, the speed and the quality of the decoded video. We describe a classification based scheme for making mode decisions in the video coding process. We then illustrate the performance of the scheme using the I/P frame selection as an example. The performance of our scheme is...

Exact closed-form analytical expressions are derived for the average bit error probability of multibranch switched diversity systems over independent and identically Nakagami-m distributed fading channels. Practical schemes that use noncoherent or differentially coherent symbol detection are considered. The general bit error probability expression derived in this paper includes as particular ca...

In this paper, we present a method for secret key generation and recovery based on iris verification that, unlike typical systems which store iris templates persistently, stores recovery information on a smart card carried by the user. The scheme uses error-correcting codes to overcome the noisiness inherent in biometric readings. Our iris template incorporates reliable region selection, reliab...

Residue Number System (RNS) are becoming popular for designing high performance DSP processors because of their ability to offer carry free arithmetic operation. The carry free operations lead to concurrent execution of arithmetic operations on the residues. However in RNS, moduli selection is one of the most important parameter that determines bit efficiency, area, power consumption, speed etc...

The Permian igneous rock in Shunbei Oilfield exhibits high strength, which results a low rate of penetration (ROP) and shortens the cutter’s service life. It is necessary to analyze evaluate breaking effect cutters. However, at this stage, evaluation has been limited comparing sizes mechanical specific energy (MSE), change efficiency caused by difference shape cutters’ surface not considered. T...

Quantum-dot Cellular Automata (QCA) is a prominent paradigm that is considered to continue its dominance in thecomputation at deep sub-micron regime in nanotechnology. The QCA realizations of five-input Majority Voter based multilevel parity generator circuits have been introduced in recent years. However, no attention has been paid towards the QCA instantiation of the generic (n-bit) even and ...

In this work, we propose a cross-layer design strategy based on a joint successive interference cancellation (SIC) detection technique and a multi-relay selection algorithm for the uplink of cooperative direct-sequence code-division multiple access (DS-CDMA) systems. We devise a low-cost greedy list-based SIC (GL-SIC) strategy with RAKE receivers as the front-end that can approach the maximum l...