This paper describes a design method of friction reducer device using loading cam to suppress unstable vibration. Nonlinear simulation and energy analysis numerical solutions demonstrates that destabilization is caused by the large phase difference between slipping velocity in translation direction rotation direction. It was found similarly vibration occurs various structures wedge rollers with...

Hydraulic fracturing is widely used to create cracks and increase the size connectivity of existing fractures, leading higher permeability shale rocks production unconventional hydrocarbon sources. The main chemicals in hydraulic fluids can initiate fractures reservoirs by acid induced carbonate dissolution, minimise energy loss during pumping process friction reducer enhanced fluid viscosity. ...

In order to improve the service life of needle roller bearing used in a precision cycloid reducer, and reveal skew collision phenomenon bearing, based on force analysis transmission mechanism reducer considering friction between wheel, roller, cage, crank shaft, dynamic contact rolling bodies is simulated by Hertz elastic contact, where cage pocket hole equivalent spring damping, nonlinear mode...

a reducer function that processes intermediate values associated with the same intermediate key. For the example of simply counting the number of terms occurring across the entire collection of documents, the mapper takes as input a document URL (key) and the document content (value) and outputs pairs of term and term count in the document. The reducer then aggregates all term counts of a term ...

a reducer function that processes intermediate values associated with the same intermediate key. For the example of simply counting the number of terms occurring across the entire collection of documents, the mapper takes as input a document URL (key) and the document content (value) and outputs pairs of term and term count in the document. The reducer then aggregates all term counts of a term ...

Cloud computing is a fast growing technology that eliminates the need to maintain expensive hardware, software and dedicated storage space. It is an on-demand computing that stores data in remote locations rather than storing in local storage attached to the computer. Big data utilizes cloud computing to store, process and analyze a large amount of data. The existing models have no prior knowle...

UNLABELLED Dental amalgam residues are probably the most important chemical residues generated from clinical dental practice because of the presence of heavy metals among its constituents, mainly mercury and silver. OBJECTIVE The purpose of this study was to develop an alternative method for the recovery of silver residues from dental amalgam. MATERIAL AND METHODS The residue generated afte...

Methane-oxidizing bacteria (MOB) gain energy from the oxidation of methane and may play important roles in freshwater ecosystems. In this study, the community structure of planktonic MOB was investigated in a subtropical reservoir. Bacterial community structure was investigated through the analysis of the 16S rRNA gene. Three groups of phylogenetically distinct MOB were detected in the clone li...

MapReduce has emerged as a successful framework for addressing the heavy demand for large-scale analytical data processing, in this peta-byte age. However, while on one hand the sheer size of data makes problems more challenging, the flexibility offered by the MapReduce frameworks on the other hand, makes the learning curve far steeper than expected. The general idea behind a MapReduce framewor...