Row-Diagonal Parity (RDP) is a new algorithm for protecting against double disk failures. It stores all data unencoded, and uses only exclusive-or operations to compute parity. RDP is provably optimal in computational complexity, both during construction and reconstruction. Like other algorithms, it is optimal in the amount of redundant information stored and accessed. RDP works within a single...

RAID (Redundant Array of Inexpensive Disks) are widely used in storage servers. Level-5 RAID is one of the most popular RAID architectures. Numerical analysis of exact Markovian dependability models of level-5 RAID architectures with orthogonal organization is unfeasible formany realisticmodel parameters due to the size of the resulting state space. In this paper we develop approximate dependab...

once the total number of disks gets large, it becomes more cost-effective to employ an array controller that uses some form of partial redundancy (such as parity) to protect the data it stores. Such RAIDs (for Redundant Arrays of Independent Disks) were first described in the early 1980s [Lawlor81, Park86], and popularized by the work of a group at UC Berkeley [Patterson88, Patterson89]. By sto...

Raid is a distributed database sy.~tel1l based on the relationalllloclel. O-Raid is an t'xtenslOIl of the Raid systelll that SlIppOrLS complex d.. ta ohif'("t~. Its (1;lt<l. model comhines properties of thl' rl'laIIOlla[ model in Raid ClUJ t.he ohject lllodel in ('++ 111 Ihis paper WI' discuss the (Iclails of illlplell1entil1~ D-Il-aid. 111 panicu[ar, we describe the organizatiolL of oh.iecls 0...

RAID systems are widely deployed, both as standalone storage solutions and as the building blocks of modern virtualised storage platforms. An accurate model of RAID system performance is therefore critical towards fulfilling quality of service constraints for fast, reliable storage. This thesis presents techniques and tools that model response times in zoned RAID systems. The inputs to this ana...

Aqueous humor (AH) is a transparent fluid which fills the anterior and posterior chambers of the eye. It supplies nutrients and removes metabolic waste from avascular tissues in the eye. Proper homeostasis of AH is required to maintain adequate intraocular pressure as well as optical and refractive properties of the eye. Application of metabolomics to study human AH may improve knowledge about ...

In black cherry (Prunus serotina Ehrh.) macerates, the cyanogenic diglucoside (R)-amygdalin undergoes stepwise degradation to HCN catalyzed by amygdalin hydrolase (AH), prunasin hydrolase, and (R)-(+)-mandelonitrile lyase (MDL). A near full-length AH cDNA clone (pAH1), whose insert encodes the isozyme AH I, has been isolated and sequenced. AH I exhibits several features characteristic of beta-g...

[Mog95] " Operating Systems Support for Busy Internet Servers " Jeffrey C. Mogul. DEC WRL Technical note 49, expanded from a paper in Proceedings of HotOS-V, pp. addendum. May 1995.

introduction: vertical root fracture inevitably leads to tooth extraction. thus, root filling with obturating materials and sealers that can reinforce the tooth would be an ideal way to reduce fracture in root treated teeth. this study aimed to assess the fracture resistance of roots following the application of different sealers including epiphany, iroot sealer and ah-plus. methods and materia...

Flash SSDs are a technology that has the potential of drastically changing the architecture of a DBMS. In this paper we examine the properties of a storage space built on SSDs with RAID and how these affect data intensive systems. While we observed the expected performance improvements of one to two orders of magnitude of SSD-only storage over HDD storage, RAID-SSD systems showed interesting ef...