Enabling the e cient storage, access and retrieval of large volumes of multi-dimensional data is one of the important emerging problems in databases. We present a framework for adaptively storing, accessing, and retrieving large images. The framework uses a space and frequency graph to generate and select image view elements for storing in the database. By adapting to user access patterns, the ...

We propose a scalable state estimator with wave filter for surface vessels. The filter is shown to be either globally or locally exponentially stable depending on configuration. Performance is illustrated using actual data from a full scale semi-submersible drilling rig.

The rheological regulation of the “three high” (high temperature, high density and high salinity) water-based drilling fluid is a worldwide problem due to the combined influence of temperature, solid content and salinity. This paper investigates the factors and regulation methods about rheological property of “three high” water based drilling fluid, and the effects of clay, salinity and weighti...

SUMMARY Foam researchers generate large, complex, time-dependent data sets with hundreds or thousands of individual bubbles and thousands of time steps. However, no foam specific visual-ization software exists. We briefly describe foam research and its challenges and we present FoamVis, a software application that provides visualization, exploration and analysis techniques for foam research.

The rate of penetration (ROP) is one of the vital parameters which directly affects the drilling time and costs. There are various parameters that influence the drilling rate; they include weight on bit, rotational speed, mud weight, bit type, formation type, and bit hydraulic. Several approaches, including mathematical models and artificial intelligence have been proposed to predict the rate o...

Metal foam heat exchangers have considerable advantages in thermal management and heat recovery over several commercially available heat exchangers. In this work, the effects of micro structural metal foam properties, such as porosity, pore and fiber diameters, tortuosity, pore density, and relative density, on the heat exchanger performance are discussed. The pertinent correlations in the lite...

Porous polyurethane foam was evaluated to replace the eight nylon meshes used as a substrate to collect nanoparticles in the Nanoparticle Respiratory Deposition (NRD) sampler. Cylindrical (25-mm diameter by 40-mm deep) foam with 110 pores per inch was housed in a 25-mm-diameter conductive polypropylene cassette cowl compatible with the NRD sampler. Pristine foam and nylon meshes were evaluated ...

Several types of foam can be found both in nature and artificial environments; yet it is rare in computer graphics due to its complexity. Modelling foam structure and dynamics by simulating the underlying bubble structure has a high computational cost. To model such a complex phenomena we need to use serious simplifications while maintaining realism and detail. In this paper we propose a method...

Ag nanoparticles-modified 3D graphene foam was synthesized through a one-step in-situ approach and then directly applied as the electrode of an electrochemical sensor. The composite foam electrode exhibited electrocatalytic activity towards Hg(II) oxidation with high limit of detection and sensitivity of 0.11 μM and 8.0 μA/μM, respectively. Moreover, the composite foam electrode for the sensor ...

The article discusses researches performed in the Well Drilling Department of the St. Petersburg Mining University. The directions of development of the department are shown. Special attention in this article is paid to research in the field of developing drilling fluids for drilling wells in various mining and geological conditions. It is shown that the gas-liquid mixtures studied by the depar...