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71.
Deqing Zou Wenrong Zhang Weizhong Qiang Guofu Xiang Laurence Tianruo Yang Hai Jin Kan Hu 《Future Generation Computer Systems》2013,29(8):2092-2102
Virtualization is a pillar technology in cloud computing for multiplexing computing resources on a single cloud platform for multiple cloud tenants. Monitoring the behavior of virtual machines (VMs) on a cloud platform is a critical requirement for cloud tenants. Existing monitoring mechanisms on virtualized platforms either takes a complete VM as the monitoring granularity, such that they cannot capture the malicious behaviors within individual VMs, or they focus on specific monitoring functions that cannot be used for heterogeneous VMs concurrently running on a single cloud node. Furthermore, the existing monitoring mechanisms have made an assumption that the privileged domain is trusted to act as expected, which causes the cloud tenants’ concern about security because the privileged domain in fact could not act as the tenants’ expectation. We design a trusted monitoring framework, which provides a chain of trust that excludes the untrusted privileged domain, by deploying an independent guest domain for the monitoring purpose, as well as utilizing the trusted computing technology to ensure the integrity of the monitoring environment. Moreover, the feature of fine-grained and general monitoring is also provided. We have implemented the proposed monitoring framework on Xen, and integrated it into OpenNebula. Our experimental results show that it can offer expected functionality, and bring moderate performance overhead. 相似文献
72.
Chi-Won In Jin-Yeon Kim Kimberly E. Kurtis Laurence J. Jacobs 《NDT & E International》2009,42(7):610-617
This research examines the application of ultrasonic Rayleigh surface waves to the non-destructive evaluation (NDE) of asphaltic concrete in the frequency range 40–100 kHz. Two ultrasonic parameters, the phase velocity and amplitude attenuation, are considered to be sensitive to local compositional and structural variations and are measured. A wedge technique is used to generate Rayleigh surface waves in an asphaltic concrete beam with uniformly distributed aggregate, and this technique is shown to be effective in launching Rayleigh waves in this highly viscoelastic (absorptive) and heterogeneous medium. Three different ultrasonic detection setups using contact and non-contact transducers as receivers are examined and their results are compared. The experimental results show that the wedge generation technique along with an air-coupled receiving transducer with a finite-size aperture is the most reliable for characterizing Rayleigh waves in asphaltic concrete. It is also experimentally demonstrated that the proposed setup may be used to detect aggregate segregation in asphaltic concrete. 相似文献
73.
Katz Jonathan F.; Adler Joan C.; Mazzarella Nicholas J.; Ince Laurence P. 《Canadian Metallurgical Quarterly》1985,30(1):53
Examined the effects of a 12-wk exercise training program on the mood states (assessed via the Profile of Mood States [POMS]) of a 27-yr-old spinal-cord-injured male in a rehabilitation hospital. S was administered the POMS immediately before and after the program and once each week during the program. S demonstrated major mood changes following exercise training, indicating a significant decrease in tension, depression, anger, fatigue, and confusion and a significant increase in vigor. Findings support the hypothesis that vigorous physical exercise can be a useful therapeutic strategy with the disabled. (27 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
74.
Cheng Hua Li Laurence T. Yang Man Lin 《International journal of parallel programming》2014,42(3):505-523
This paper studies parallel training of an improved neural network for text categorization. With the explosive growth on the amount of digital information available on the Internet, text categorization problem has become more and more important, especially when millions of mobile devices are now connecting to the Internet. Improved back-propagation neural network (IBPNN) is an efficient approach for classification problems which overcomes the limitations of traditional BPNN. In this paper, we utilize parallel computing to speedup the neural network training process of IBPNN. The parallel IBNPP algorithm for text categorization is implemented on a Sun Cluster with 34 nodes (processors). The communication time and speedup for the parallel IBPNN versus various number of nodes are studied. Experiments are conducted on various data sets and the results show that the parallel IBPNN together with SVD technique achieves fast computational speed and high text categorization correctness. 相似文献
75.
Yves Denizot Laurence Michel Jacques Benveniste Alain Meybeck Yolène Thomas Louis Duberfret 《Lipids》1991,26(12):1093-1094
Paf is a phospholipid mediator present in human skin which induces inflammatory events such as neutrophil infiltration and
increased vascular permeability. Recent data suggest that cutaneous cells, such as fibroblasts and keratinocytes, produce
paf and that paf is released during allergic cutaneous reactions. It is tempting to speculate that paf may contribute to the
development of various skin disorders with acute and chronic skin inflammation. Paf antagonists may help in bringing answers
to this hypothesis and may offer new prospects for the treatment of cutaneous inflammatory diseases.
Based on a paper presented at the Third International Conference on Platelet-Activating Factor and Structurally Related Alkyl
Ether Lipids, Tokyo, Japan, May 1989. 相似文献
76.
Effect of water‐absorbing nanospheres on antistatic property of isotactic polypropylene fibers 下载免费PDF全文
Hongxing Liu Jianguo Tang Yao Wang Linjun Huang Yanxin Wang Jiqing Jiao Jixian Liu Zhichao Xin Laurence A. Belfiore 《应用聚合物科学杂志》2014,131(15)
In this article, novel antistatic isotactic polypropylene (iPP) fibers were prepared through adding ternary polymer water‐absorbing nanospheres (TPWANs) into iPP melt in melt spinning process. The TPWANs were synthesized through emulsion copolymerization of styrene (St), butyl acrylate (BA), and sodium allylsulfonate (SAS). The characterization results of Fourier transform infrared spectrometer (FT‐IR) and 1H nuclear magnetic resonance (1H NMR) confirmed the ternary components in this copolymer. Transmission electron microscopy (TEM) images indicated the nanospherical shape of TPWANs with the characteristics of 80–90 nm size range of diameter and good dispersion in iPP fibers. The volume resistance of iPP fibers decreased by three orders from 1012 to 109 Ω cm when the 6 wt % TPWANs was added into iPP fibers, indicating that the blend fibers have good antistatic property. Most importantly, the nanospherical structure of TPWANs imparts both the compatibility and antistatic property into the blend iPP fibers. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40568. 相似文献
77.
The first results on a simple new process for the direct fabrication of one-dimensional superlattices using common CVD chambers are presented. The experiments were carried out in a 200?mm industrial Centura reactor (Applied Materials). Low dimensionality and superlattices allow a significant increase in the figure of merit of thermoelectrics by controlling the transport of phonons and electrons. The monocrystalline nanowires produced according to this process are both one-dimensional and present heterostructures, with very thin layers (40?nm) of Si and SiGe. Concentrations up to 30?at.% Ge were obtained in the SiGe parts. Complementary techniques including transmission electronic microscopy (TEM), selected area electron diffraction (SAED), energy dispersive x-ray spectroscopy (EDS), scanning transmission electron microscopy (STEM) in bright field and high angle annular dark field (HAADF STEM), and energy-filtered transmission electron microscopy (EF-TEM) were used to characterize the nanoheterostructures. 相似文献
78.
Satoshi Hirayama Shozo Takagi Milenko Markovic Laurence C. Chow 《Journal of research of the National Institute of Standards and Technology》2008,113(6):311-320
Calcium phosphate cements (CPCs) were prepared using mixtures of tetracalcium phosphate (TTCP) and dicalcium phosphate anhydrous (DCPA), with TTCP/DCPA molar ratios of 1/1, 1/2, or 1/3, with the powder and water as the liquid. Diametral tensile strength (DTS), porosity, and phase composition (powder x-ray diffraction) were determined after the set specimens have been immersed in a physiological-like solution (PLS) for 1 d, 5 d, and 10 d. Cement dissolution rates in an acidified PLS were measured using a dual constant composition method. Setting times ((30 ± 1) min) were the same for all cements. DTS decreased with decreasing TTCP/DCPA ratio and, in some cases, also decreased with PLS immersion time. Porosity and hydroxyapatite (HA) formation increased with PLS immersion time. Cements with TTCP/DCPA ratios of 1/2 and 1/3, which formed calcium-deficient HA, dissolved more rapidly than the cement with a ratio of 1/1. In conclusion, cements may be prepared with a range of TTCP/DCPA ratios, and those with lower ratio had lower strengths but dissolved more rapidly in acidified PLS. 相似文献
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