The main task of drilling the formation by the bit is done via scraping, crushing and grinding. Discharging the fluid from the bit nozzles is done with high pressure which assists to break the rocks. Different parameters affect the bit selection and design for each drilling formation, but the most important one is drillability that depends on hardness of the formation. In this paper, the design...

the bft approach is used to formulate the electronic states in graphene through a non-commutative space in the presence of a constant magnetic field b for the first time. in this regard, we introduce a second class of constrained system, which is not gauge symmetric but by applying bft method and extending phase space, the second class constraints  converts  to the first class constraints so th...

measurement of the loads exerted on the limb is a fundamental part of designing of an assistive device, which has been done by using strain gauges or a transducer. although calculation of loads applied on an orthosis coefficients achieved from calibration is a standard way, most of researchers determined the loads based on available equations. therefore, the aim of this research is finding the ...

In recent decades, the impact of climate change on urban flooding has increased, along with an increase in population and areas. Hence, historical design storms require revisions based robust intensity–duration–frequency (IDF) relationships. To this end, development rain-gauge network is essential to yield spatiotemporal attributes rainfall. The present study addresses two objectives: (a) recon...

[1] Satellite gravity measurements from the Gravity Recovery and Climate Experiment (GRACE) provide new quantitative measures of the 2005 extreme drought event in the Amazon river basin, regarded as the worst in over a century. GRACE measures a significant decrease in terrestrial water storage (TWS) in the central Amazon basin in the summer of 2005, relative to the average of the 5 other summer...

Rainfall data is useful in many fields such as urban management, agriculture, and so on. Spatial interpolation is widely used to interpolation continue rainfall data from discrete rainfall gauges. The uncertainty in spatial interpolation is change in different region. Paper focus on urban small area of Beijing city, Xicheng District and analyses uncertainty of spatial interpolation from four as...

Wireless access networks based in millimetre wavelength technologies are mainly impaired by rain. To evaluate the rain effects over a communication system, it is essential to know the temporal and spatial evolution of rainfall rate. For this reason, it is necessary to develop an experimental network which provides the adequate data to study, prevent and compensate the rain fade. In this paper, ...