Guangyan Zhang

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Round-robin striping, due to its uniform distribution and low-complexity computation, is widely used by applications which demand high bandwidth and massive storage. Because many systems are nonstoppable when their storage capacity and I/O bandwidth need increasing, an efficient and online mechanism to add more disks to striped volumes is very important. In(More)
Disk additions to anRAID-6 storage system can increase the I/O parallelism and expand the storage capacity simultaneously. To regain loadbalanceamongall disks includingold and new,RAID-6 scaling requiresmoving certain data blocks onto newly addeddisks. Existing approaches toRAID-6 scaling, restricted bypreserving a round-robin data distribution,(More)
With the development of storage technology and applications, new caching policies are continuously being introduced. It becomes increasingly important for storage systems to be able to select the matched caching policy dynamically under varying workloads. This article proposes SOPA, a cache framework to adaptively select the matched policy and perform(More)
Disk additions to a RAID-4 storage system can increase the I/O parallelism and expand the storage capacity simultaneously. To regain load balance among all disks including old and new, RAID-4 scaling requires moving certain data blocks onto newly added disks. Existing data redistribution approaches to RAID-4 scaling, restricted by preserving a round-robin(More)
To achieve high energy efficiency and low response time in big data stream computing environments, it is required to model an energy-efficient resource scheduling and optimization framework. In this paper, we propose a real-time and energy-efficient resource scheduling and optimization framework, termed the Re-Stream. Firstly, the Re-Stream profiles a(More)
Polyaspartamide-based disulfide-containing brushed polyethylenimine derivatives P(Asp-Az)X-SS-PEIs were synthesized via click chemistry and evaluated as nonviral gene delivery carrier. First, azide-functional poly(aspartic acid) derivatives with various azide-group densities and monoalkyne-terminated PEI with disulfide linkages were synthesized. Then, click(More)
Range-aggregate queries are to apply a certain aggregate function on all tuples within given query ranges. Existing approaches to range-aggregate queries are insufficient to quickly provide accurate results in big data environments. In this paper, we propose FastRAQ-a fast approach to range-aggregate queries in big data environments. FastRAQ first divides(More)