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992.
Multiple Internet applications are often hosted in one datacenter, sharing underlying virtualized server resources. It is important to provide differentiated treatment to co-hosted applications and to improve overall system performance by efficient use of shared resources. Challenges arise due to multi-tier service architecture, virtualized server infrastructure, and highly dynamic and bursty workloads. We propose a coordinated admission control and adaptive resource provisioning approach for multi-tier service differentiation and performance improvement in a shared virtualized platform. We develop new model-independent reinforcement learning based techniques for virtual machine (VM) auto-configuration and session based admission control. Adaptive VM auto-configuration provides proportional service differentiation between co-located applications and improves application response time simultaneously. Admission control improves session throughput of the applications and minimizes resource wastage due to aborted sessions. A shared reward actualizes coordination between the two learning modules. For system agility and scalability, we integrate the reinforcement learning approach with cascade neural networks. We have implemented the integrated approach in a virtualized blade server system hosting RUBiS benchmark applications. Experimental results demonstrate that the new approach meets differentiation targets accurately and achieves performance improvement of applications at the same time. It reacts to dynamic and bursty workloads in an agile and scalable manner. 相似文献
993.
994.
Jian Zhou 《Electrochimica acta》2003,48(18):2571-2582
The effect on cycle capacity is reported of cathode material (metal oxide, carbon, and current collector) in lithium/metal oxide cells cycled with fumed silica-based composite electrolytes. Three types of electrolytes are compared: filler-free electrolyte consisting of methyl-terminated poly(ethylene glycol) oligomer (PEGdm, Mw=250)+lithium bis(trifluromethylsufonyl)imide (LiTFSI) (Li:O=1:20), and two composite systems of the above baseline liquid electrolyte containing 10-wt% A200 (hydrophilic fumed silica) or R805 (hydrophobic fumed silica with octyl surface group). The composite electrolytes are solid-like gels. Three cathode active materials (LiCoO2, V6O13, and LixMnO2), four conducting carbons (graphite Timrex® SFG 15, SFG 44, carbon black Vulcan XC72R, and Ketjenblack EC-600JD), and three current collector materials (Al, Ni, and carbon fiber) were studied. Cells with composite electrolytes show higher capacity, reduced capacity fade, and less cell polarization than those with filler-free electrolyte. Among the three active materials studied, V6O13 cathodes deliver the highest capacity and LixMnO2 cathodes render the best capacity retention. Discharge capacity of Li/LiCoO2 cells is affected greatly by cathode carbon type, and the capacity decreases in the order of Ketjenblack>SFG 15>SFG 44>Vulcan. Current collector material also plays a significant role in cell cycling performance. Lithium/vanadium oxide (V6O13) cells deliver increased capacity using Ni foil and carbon fiber current collectors in comparison to an Al foil current collector. 相似文献
995.
Xu Zhou YanTao Zhou KenLi Li Ahmed Sallam Keqin Li 《The Journal of supercomputing》2014,69(2):976-1005
The tile assembly model is a novel biological computing model where information is encoded in DNA tiles. It is an efficient way to solve NP-complete problems due to its scalability and parallelism. In this paper, we apply the tile assembly model to solve the minimum and exact set cover problems, which are well-known NP-complete problems. To solve the minimum set cover problem, we design a MinSetCover system composed of three parts, i.e., the seed configuration subsystem, the nondeterministic choice subsystem, and the detection subsystem. Moreover, we improve the MinSetCover system and propose a MinExactSetCover system for solving the problem of exact cover by 3-sets. Finally we analyze the computation complexity and perform a simulation experiment to verify the effectiveness and correctness of the proposed systems. 相似文献
996.
介绍了硬质陶器低温烧成的研究及其结果。研究表明,用优质高岭土与一定粒度的石灰石和硅石按适量配比配料,有助于低温烧制抗弯强度超过60MPa的高强硬质陶器。 相似文献
997.
998.
Ian Turk Matthew Sin Xin''an Zhou Jun Tao Chaoli Wang Qi Liao 《International Journal of Software and Informatics》2016,10(3)
We present a visual analytics system to understand the operation data of a
company, GAStech, from IEEE VAST Challenge 2016. The data include proximity data
recording the locations and movements of employees, and heating, ventilation, and air
conditioning (HVAC) data recording the environmental conditions in the building.
Analyzing the data to detect the suspicious behaviors of some disgruntled employees is of
special interest. Our system provides coordinated multiple views to visualize the proximity
data and the HVAC data over time. Visual hints and comparisons are designed for users to
identify abnormal patterns and compare them. Furthermore, the system automatically
detects and correlates the anomalies in the data. We provide use cases to demonstrate the
effectiveness of our system. 相似文献
999.
1000.
研究了新型无机复合混凝剂ISF-01对日用化学工业废水的絮凝、破乳效果及混凝剂用量和体系pH值对混凝效果的影响,并与其它无机絮凝剂进行了比较。试验结果表明.ISF-01混凝剂有较宽的pH适用范围,对日用化学工业废水具有良好的混凝效果,与传统混凝剂相比,它具有破乳性能好、投药量少、絮体沉降速度快、上清液透光性能好的特点。 相似文献