Severe environment in deep ocean affects operating reliability and security of coring drill. Adopting heave motion signal measured by accelerometer to confirm heave compensation of coring drill, the compensation control method is proposed using disturbance observer to restrain the disturbance. Then, the disturbance observer is designed. The heave motion simulation for coring drill is done with ...

CMC polymer is used as an additive to decrease water loss and mud-cake-thickness in mud drilling. In this study, the effect of CMC and CMC nanoparticles on water loss and mud-cake-thickness in mud drilling is investigated. CMC nanoparticles are made by using of ball milling and their size is measured by Particle size analyzer. CMC and CMC nanoparticles which were prepared by Hamilton batch mixe...

Due to the lower tool as the research object to analyze the vibration of the drill string, causes the loss of the low order natural frequency of the drill string and the inherent vibration mode, give rise to the distortion and error of the result from the transient analysis of the drill string. For this purpose, the whole drill string of the deep wells is studied in the article, build the mecha...

Abrtnxcl-In this contribution wa p r ~ p a ~ now1 Coded Modulation auhtad Genatic Algorithm based hrfultirwr Detection (CM-GA-MUD) scheme for synchronous CDhrIA systems. The parfonnnnce of the p r o p 4 acheme WIU invatigatad ruing QusdraturaPhsraShift-Keying (QPSK), when communiuting over AWGN m d narrowband Rqyleigh fading chnnneb. When cumpard with the optimum MUD acheme. the CA-MUD subsytta...

In the Bayer process of extraction of alumina from bauxite, the insoluble product generated after bauxite digestion with sodium hydroxide at elevated temperature and pressure is known as ̳red mud‘ or ̳bauxite residue‘. Enormous quantity of red mud is generated worldwide every year posing a very serious and alarming environmental problem. This paper describes the production and characterization ...

There is little question that current role-playing MUD systems provide entertainment for their users. Nevertheless, experience with these systems, however entertaining, often falls short of the compelling, rich and varied experiences we associate with dramatic art. This limitation is in part due to the nature of control in MUDs. Control within a MUD is, by de nition, distributed; unlike convent...

An investigation was conducted to estimate approximate production and assess the marketing of mud crab in the south-western region of Bangladesh. Crab culture was done by hardening and fattening collected from the natural source. Most of the fattening farms were 0.2 to 2 acres. Fattening and hardening period varied from 10 to 30 days. The Sundarban mangrove, tidal rivers, estuaries, canals, shr...

Based on the minimum mean squared error (MMSE) between the data stream and the linear combiner output, a new multiuser detection (MUD) algorithm that combines space–time (ST) processing and antenna array on directsequence CDMA signals is proposed. The proposed ST-MUD algorithm is proved to be equivalent to two existing MMSE-based ST-MUD algorithms, and the theoretical BER performances for all t...

This paper analyzes performance of optimal channel estimation and multiuser detection (MUD) in a block-fading code-division multiple-access (CDMA) channel on the assumptions of random spreading and large-system limit, by using the replica method developed in statistical mechanics. The authors find that the asymptotic spectral efficiency of the linear minimum mean-squared error (LMMSE) MUD which...

In automation flexible manufacturing systems, tool wear detection during the cutting process is one of the most important considerations. This study presents an intelligent system for online tool condition monitoring in drilling process .In this paper, analytical and empirical models have been used to predict the thrust and cutting forces on the lip and chisel edges of a new drill. Also an empi...