University of Rhode Island

About: University of Rhode Island is a education organization based out in Kingston, Rhode Island, United States. It is known for research contribution in the topics: Population & Bay. The organization has 11464 authors who have published 22770 publications receiving 841066 citations. The organization is also known as: URI & Rhode Island College of Agriculture and the Mechanic Arts.

I-CASH: Intelligently Coupled Array of SSD and HDD

Abstract: This paper presents a new disk I/O architecture composed of an array of a flash memory SSD (solid state disk) and a hard disk drive (HDD) that are intelligently coupled by a special algorithm. We call this architecture I-CASH: Intelligently Coupled Array of SSD and HDD. The SSD stores seldom-changed and mostly read reference data blocks whereas the HDD stores a log of deltas between currently accessed I/O blocks and their corresponding reference blocks in the SSD so that random writes are not performed in SSD during online I/O operations. High speed delta compression and similarity detection algorithms are developed to control the pair of SSD and HDD. The idea is to exploit the fast read performance of SSDs and the high speed computation of modern multi-core CPUs to replace and substitute, to a great extent, the mechanical operations of HDDs. At the same time, we avoid runtime SSD writes that are slow and wearing. An experimental prototype I-CASH has been implemented and is used to evaluate I-CASH performance as compared to existing SSD/HDD I/O architectures. Numerical results on standard benchmarks show that I-CASH reduces the average I/O response time by an order of magnitude compared to existing disk I/O architectures such as RAID and SSD/HDD storage hierarchy, and provides up to 2.8 speedup over state-of-the-art pure SSD storage. Furthermore, I-CASH reduces random writes to SSD implying reduced wearing and prolonged life time of the SSD.

Nanoparticles meet cell membranes: probing nonspecific interactions using model membranes.

Abstract: Nanotoxicity studies have shown that both carbon-based and inorganic engineered nanoparticles can be toxic to microorganisms. While the pathways for cytotoxicity are diverse and dependent upon the ...

Regional-scale chemical transport modeling in support of the analysis of observations obtained during the TRACE-P experiment

Abstract: [1] Data obtained during the TRACE-P experiment is used to evaluate how well the CFORS/STEM-2K1 regional-scale chemical transport model is able to represent the aircraft observations. Thirty-one calculated trace gas and aerosol parameters are presented and compared to the in situ data. The regional model is shown to accurately predict many of the important features observed. The mean values of all the model parameters in the lowest 1 km are predicted within ±30% of the observed values. The correlation coefficients (R) for the meteorological parameters are found to be higher than those for the trace species. For example, for temperature, R > 0.98. Among the trace species, ethane, propane, and ozone show the highest values (0.8 < R < 0.9), followed by CO, SO2, and NOy. NO and NO2 had the lowest values (R < 0.4). Analyses of pollutant transport into the Yellow Sea by frontal events are presented and illustrate the complex nature of outflow. Biomass burning from SE Asia is transported in the warm conveyor belt at altitudes above ∼2 km and at latitudes below 30N. Outflow of pollution emitted along the east coast of China in the postfrontal regions is typically confined to the lower ∼2 km and results in high concentrations with plume-like features in the Yellow Sea. During these situations the model underpredicts CO and black carbon (among other species). An analysis of ozone production in this region is also presented. In and around the highly industrialized regions of East Asia, where fossil fuel usage dominates, ozone is NMHC-limited. South of ∼30–35N, ozone production is NOx-limited, reflecting the high NMHC/NOx ratios due to the large contributions to the emissions from biomass burning, biogenics sources, and biofuel usage in central China and SE Asia.