The Experts below are selected from a list of 324 Experts worldwide ranked by ideXlab platform
Jose Pereira - One of the best experts on this subject based on the ideXlab platform.
-
efficient deduplication in a distributed primary storage infrastructure
ACM Transactions on Storage, 2016Co-Authors: Joao Paulo, Jose PereiraAbstract:A large amount of duplicate data typically exists across volumes of virtual machines in cloud computing infrastructures. Deduplication allows reclaiming these duplicates while improving the cost-effectiveness of large-scale multitenant infrastructures. However, traditional archival and backup deduplication systems impose prohibitive storage overhead for virtual machines hosting latency-sensitive applications. Primary deduplication systems reduce such penalty but rely on special cluster filesystems, centralized components, or restrictive workload assumptions. Also, some of these systems reduce storage overhead by confining deduplication to off-peak periods that may be scarce in a cloud environment. We present DEDIS, a dependable and fully decentralized system that performs cluster-wide off-line deduplication of virtual machines’ primary volumes. DEDIS works on top of any unsophisticated storage backend, centralized or distributed, as long as it exports a basic shared block Device Interface. Also, DEDIS does not rely on data locality assumptions and incorporates novel optimizations for reducing deduplication overhead and increasing its reliability. The evaluation of an open-source prototype shows that minimal I/O overhead is achievable even when deduplication and intensive storage I/O are executed simultaneously. Also, our design scales out and allows collocating DEDIS components and virtual machines in the same servers, thus, sparing the need of additional hardware.
-
Distributed Exact Deduplication for Primary Storage Infrastructures
2014Co-Authors: Joao Paulo, Jose PereiraAbstract:Deduplication of primary storage volumes in a cloud computing environment is increasingly desirable, as the resulting space savings contribute to the cost effectiveness of a large scale multi-tenant infrastructure. However, traditional archival and backup deduplication systems impose prohibitive overhead for latency-sensitive applications deployed at these infrastructures while, current primary deduplication systems rely on special cluster filesystems, centralized components, or restrictive workload assumptions.We present DEDIS, a fully-distributed and dependable system that performs exact and cluster-wide background deduplication of primary storage. DEDIS does not depend on data locality and works on top of any unsophisticated storage backend, centralized or distributed, that exports a basic shared block Device Interface. The evaluation of an open-source prototype shows that DEDIS scales out and adds negligible overhead even when deduplication and intensive storage I/O run simultaneously.
Yoshiyori Urano - One of the best experts on this subject based on the ideXlab platform.
-
a word based predictive text entry method for khmer language
Information Reuse and Integration, 2008Co-Authors: Mitsuji Matsumoto, Yoshiyori UranoAbstract:This paper begins with a discussion on the difficulties in applying word-based text entry method for Khmer, official language of Cambodia. Then, we propose a word-based predictive method based on careful analysis on the structure of current Khmer typing system. To evaluate the proposed text entry, we designed and implemented two Interface prototypes; the 12-key mobile phone Interface and the stylus-based Device Interface such as Personal Digital Assistant (PDA). Results show that compared to the existing methods our model provides better keystrokes and speed.
-
IRI - A word-based predictive text entry method for Khmer language
2008 IEEE International Conference on Information Reuse and Integration, 2008Co-Authors: Mitsuji Matsumoto, Yoshiyori UranoAbstract:This paper begins with a discussion on the difficulties in applying word-based text entry method for Khmer, official language of Cambodia. Then, we propose a word-based predictive method based on careful analysis on the structure of current Khmer typing system. To evaluate the proposed text entry, we designed and implemented two Interface prototypes; the 12-key mobile phone Interface and the stylus-based Device Interface such as Personal Digital Assistant (PDA). Results show that compared to the existing methods our model provides better keystrokes and speed.
Rashitovich Fljur Ismagilov - One of the best experts on this subject based on the ideXlab platform.
-
Evaluating 3D printing to solve the sample-to-Device Interface for LRS and POC diagnostics: Example of an interlock meter-mix Device for metering and lysing clinical urine samples
Lab on a Chip, 2016Co-Authors: Erik Jue, Nathan G. Schoepp, Daan Witters, Rashitovich Fljur IsmagilovAbstract:This paper evaluates the potential of 3D printing, a semi-automated additive prototyping technology, as a means to design and prototype a sample-to-Device Interface, amenable to diagnostics in limited-resource settings, where speed, accuracy and user-friendly design are critical components. As a test case, we built and validated an interlock meter-mix Device for accurately metering and lysing human urine samples for use in downstream nucleic acid amplification. Two plungers and a multivalve generated and controlled fluid flow through the Device and demonstrate the utility of 3D printing to create leak-free seals. Device operation consists of three simple steps that must be performed sequentially, eliminating manual pipetting and vortexing to provide rapid (5 to 10 s) and accurate metering and mixing. Bretherton's prediction was applied, using the bond number to guide a design that prevents potentially biohazardous samples from leaking from the Device. We employed multi-material 3D printing technology, which allows composites with rigid and elastomeric properties to be printed as a single part. To validate the meter-mix Device with a clinically relevant sample, we used urine spiked with inactivated Chlamydia trachomatis and Neisseria gonorrhoeae. A downstream nucleic acid amplification by quantitative PCR (qPCR) confirmed there was no statistically significant difference between samples metered and mixed using the standard protocol and those prepared with the meter-mix Device, showing the 3D-printed Device could accurately meter, mix and dispense a human urine sample without loss of nucleic acids. Although there are some limitations to 3D printing capabilities (e.g. dimension limitations related to support material used in the printing process), the advantages of customizability, modularity and rapid prototyping illustrate the utility of 3D printing for developing sample-to-Device Interfaces for diagnostics.
Joao Paulo - One of the best experts on this subject based on the ideXlab platform.
-
efficient deduplication in a distributed primary storage infrastructure
ACM Transactions on Storage, 2016Co-Authors: Joao Paulo, Jose PereiraAbstract:A large amount of duplicate data typically exists across volumes of virtual machines in cloud computing infrastructures. Deduplication allows reclaiming these duplicates while improving the cost-effectiveness of large-scale multitenant infrastructures. However, traditional archival and backup deduplication systems impose prohibitive storage overhead for virtual machines hosting latency-sensitive applications. Primary deduplication systems reduce such penalty but rely on special cluster filesystems, centralized components, or restrictive workload assumptions. Also, some of these systems reduce storage overhead by confining deduplication to off-peak periods that may be scarce in a cloud environment. We present DEDIS, a dependable and fully decentralized system that performs cluster-wide off-line deduplication of virtual machines’ primary volumes. DEDIS works on top of any unsophisticated storage backend, centralized or distributed, as long as it exports a basic shared block Device Interface. Also, DEDIS does not rely on data locality assumptions and incorporates novel optimizations for reducing deduplication overhead and increasing its reliability. The evaluation of an open-source prototype shows that minimal I/O overhead is achievable even when deduplication and intensive storage I/O are executed simultaneously. Also, our design scales out and allows collocating DEDIS components and virtual machines in the same servers, thus, sparing the need of additional hardware.
-
Distributed Exact Deduplication for Primary Storage Infrastructures
2014Co-Authors: Joao Paulo, Jose PereiraAbstract:Deduplication of primary storage volumes in a cloud computing environment is increasingly desirable, as the resulting space savings contribute to the cost effectiveness of a large scale multi-tenant infrastructure. However, traditional archival and backup deduplication systems impose prohibitive overhead for latency-sensitive applications deployed at these infrastructures while, current primary deduplication systems rely on special cluster filesystems, centralized components, or restrictive workload assumptions.We present DEDIS, a fully-distributed and dependable system that performs exact and cluster-wide background deduplication of primary storage. DEDIS does not depend on data locality and works on top of any unsophisticated storage backend, centralized or distributed, that exports a basic shared block Device Interface. The evaluation of an open-source prototype shows that DEDIS scales out and adds negligible overhead even when deduplication and intensive storage I/O run simultaneously.
Felicity Jowi - One of the best experts on this subject based on the ideXlab platform.
-
the active urine collection Device a novel continence management system focusing particularly on the needs of disabled women
Disability and Rehabilitation, 2000Co-Authors: E Tinnio, Felicity JowiAbstract:Purpose : This paper introduces a novel incontinence management system which applies space technology to the problem of urinary incontinence. The purpose of this paper is to invite comments and suggestions from professionals in the disability and rehabilitation field. Method : Severe urinary incontinence is a distressing condition for which there are few satisfactory management solutions. We have been able to develop a compact liquid handling system that can cope with the initial surge of urine which characteristically reaches a high flow rate of around 25 ml/sec. By using a sophisticated system of filters, the Device can cope with mixed streams of urine and air which are inevitable when a non-invasive patient/Device Interface is used. The next phase of the project is to develop prototype Devices with the aid of users to produce an effective appliance that users and carers find practical and acceptable to use. Conclusion : With the aid of users, carers and rehabilitation experts we hope to develop an exce...