Comprehensive comparison of cloud-based NGS data analysis and alignment tools

Next-Generation Sequencing (NGS) is very helpful for conducting DeoxyriboNucleic Acid (DNA) Sequencing. DNA sequencing is the process for determining the order (sequence) of the main chemical bases in the DNA. Analyzing human DNA sequencing is important for determining the possibility that a person will develop certain diseases, and/or the ability to respond to medication. However, the NGS process is a complicated and resource-hungry technical process. To solve this dilemma, the majority of NGS software systems are deployed as cloud-based services distributed over cloud-based platforms. Cloud-based platforms provide promising solutions for the computationally intensive tasks required by the NGS data analysis. This work provides a comprehensive investigation of cloud-based NGS data analysis and alignment tools, both the commercial and the open-source tools. We also discuss in detail the main features and setup requirements for each tool, and then compare and contrast between them. Moreover, we extensively analyze and classify the studied NGS data analysis and alignment tools to help NGS biomedical researchers and clinicians in finding appropriate tools for their work, while understanding the similarities and the differences between them

Deep insights to transient pressure behavior and stabilized productivity index of multilateral wells in laterally and spatially anisotropic reservoirs

The objective of this paper is focusing deep insights on stabilized productivity index (PI) and transient pressure behaviors and flow regimes of multilateral wells. It introduces an integrated approach for the performance of reservoirs depleted by multilateral wells extending in arbitrary trajectories. The study introduces new practical solutions for estimating stabilized pseudo-steady state (PSS) productivity index and starting time of PSS as well as transient PI behavior of multilateral wells in single and dual porous media with laterally and spatially anisotropic characteristics

An experimental study of improved oil recovery through fines-assisted waterflooding

Permeability decline during waterflooding by varying water composition, in particular with low salinity or high pH water, has been observed in numerous laboratory studies. This has been explained by the lifting, migration and subsequent plugging of pores by fine particles. Recently, mathematical models have been presented to investigate the concept of using this permeability decline for mobility control during a waterflood. Now, these models need to be tested against observations during a core flood test.This paper presents a systematic laboratory study to investigate the underlying physics mechanisms for improved oil recovery as a consequence of injecting low-salinity water. Three sister plugs of Berea sandstone were used in the experiments. The first plug was subjected to single-phase waterflood for permeability measurements with varying salinities from 4 (high-salinity) to 0 (low-salinity) g/L NaCl. Core permeability decreased from 495 to 60. md, confirming the effect of changing water composition on permeability. The second plug saturated with high-salinity water was subjected first to primary oil flood (using Soltrol) to the connate water saturation and then to a benchmark waterflood using the same water. The oil recovery was noted and the core was restored to the connate water by a secondary oil flood. Finally, low-salinity waterflood was carried out and oil recovery was recorded. Experimental observations were interpreted using a numerical model. In order to check the reproducibility of the observations, the same experimental procedure was applied on the third plug. Results confirmed the reproducibility of the observations.Significant decrease in water relative permeability by approximately 50% and some decrease in residual oil saturation by about 5% were observed during the low-salinity waterflood in comparison with the high-salinity waterflood. Treatment of the low-salinity coreflood data by a numerical model reveals the decrease in water relative permeability with increasing water saturation at high water saturations. This observation is explained by the expansion of rock surface exposed to low-salinity water during the increase of water saturation. The laboratory data matched by the numerical model shows a high surface exponent value (nA=30), which is explained by a sharp surface area rise at high water saturations. The abnormal behavior of water relative permeability in response to low-salinity waterflood has resulted from matching water permeability increase at low water saturations and decrease at high saturations.© 2013.F. Hussain, A. Zeinijahromi, P. Bedrikovetsky, A. Badalyan, T. Carageorgos, Y. Cina