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51.
We propose tackling a “mini challenge” problem: a nontrivial verification effort that can be completed in 2–3 years, and will
help establish notational standards, common formats, and libraries of benchmarks that will be essential in order for the verification
community to collaborate on meeting Hoare’s 15-year verification grand challenge. We believe that a suitable candidate for
such a mini challenge is the development of a filesystem that is verifiably reliable and secure. The paper argues why we believe a filesystem is the right candidate for a mini challenge and describes
a project in which we are building a small embedded filesystem for use with flash memory.
The work described in this paper was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under
a contract with the National Aeronautics and Space Administration. 相似文献
52.
53.
A detailed chemisorption mechanism is proposed for the atomic layer deposition (ALD) of aluminium oxide nano layers using
trimethyl aluminum (TMA) and water as precursors. Six possible chemisorption mechanisms, complete ligand exchange, partial
ligand exchange, simple dissociation, complete dissociation via ligand exchange, complete dissociation and association, are
proposed and related parameters like ligand to metal ratio (L/M), concentrations of metal atoms and methyl groups adsorbed
are calculated and compared against reported values. The maximum number of methyl groups that can get attached on the surface
is calculated in a different way which yields a more realistic value of 6·25 per nm2 substrate area. The dependence of the number of metal atoms adsorbed on OH concentration is explained clearly. It is proposed
that a combination of complete ligand exchange and complete dissociation is the most probable chemisorption mechanism taking
place at various OH concentrations. 相似文献
54.
55.
Zhiling Lan Jiexing Gu Ziming Zheng Rajeev Thakur Susan Coghlan 《Journal of Parallel and Distributed Computing》2010
Despite years of study on failure prediction, it remains an open problem, especially in large-scale systems composed of vast amount of components. In this paper, we present a dynamic meta-learning framework for failure prediction. It intends to not only provide reasonable prediction accuracy, but also be of practical use in realistic environments. Two key techniques are developed to address technical challenges of failure prediction. One is meta-learning to boost prediction accuracy by combining the benefits of multiple predictive techniques. The other is a dynamic approach to dynamically obtain failure patterns from a changing training set and to dynamically extract effective rules by actively monitoring prediction accuracy at runtime. We demonstrate the effectiveness and practical use of this framework by means of real system logs collected from the production Blue Gene/L systems at Argonne National Laboratory and San Diego Supercomputer Center. Our case studies indicate that the proposed mechanism can provide reasonable prediction accuracy by forecasting up to 82% of the failures, with a runtime overhead less than 1.0 min. 相似文献
56.
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58.
Impact of gamma irradiation on the antinutritional constituents of seeds of Mucuna pruriens was assessed on exposing to doses of 2.5, 5.0, 7.5, 10, 15 and 30 kGy. Except for 2.5 kGy, the rest showed significant dose-dependent increase in phenolics. Tannin concentration did not differ significantly up to 7.5 kGy, while it significantly increased at higher doses. Excluding 2.5 kGy, the rest of the treatments showed significant decreases in the phytic acid and complete degradation was attained at 15 and 30 kGy. The l-DOPA concentration showed a dose-dependent decline. A trace amount of hemagglutination activity was seen on human erythrocytes in raw seeds, which was completely absent on irradiation (>5 kGy). Concentration of Polonium-210, a natural radionuclide falls within the admissible limits for consumption. As Mucuna seeds serve as food, feed or as pharmaceuticals, it may be necessary to set the ionizing radiation to a specific dose to retain optimum levels or to eliminate phenolics, tannins, phytic acid and L-DOPA. As irradiation is a physical and cold process, it may be ideal and emerge as an important technique to improve the nutritional or pharmaceutical quality of Mucuna seeds and its products. 相似文献
59.
Anil Kumar Mandeep Kaur Rajeev Kumar Pinaki Ranjan Sengupta Vasantha Raman Gopal Bhatia Kedar Nath Sood 《Journal of Materials Science》2010,45(5):1393-1400
Carbon–copper composites with varying copper to carbon ratio of 0.66–1.5 (by weight) were developed from coal-tar-pitch-derived
green coke (as such or modified with natural graphite) as carbon source and electrolytic grade copper powder at different
heat treatment temperatures (HTTs) of 1000–1400 °C. The physical, mechanical, and electrical properties differ depending upon
the HTT and also on copper to carbon ratio (Cu/C). The composites prepared at HTT of 1100 °C having Cu/C ratio of 0.66 and
0.9 exhibited a high bending strength of 150 and 140 MPa, bulk density of 2.63 and 2.81 gm/cm3, electrical resistivity of 1.6 and 0.96 m Ω cm and shore hardness of 88 and 84, respectively, in spite of well-known inadequate
wettability between copper and carbon. Increasing the temperature from 1100 °C for processing of the composites deteriorated
the properties mainly due to the loss of copper through melting above 1100 °C as revealed by X-ray, scanning electron microscopy,
thermal analysis and EDAX studies. 相似文献
60.
Nishad A. Phatak Shrinivas R. Kulkarni Vadym Drozd Surendra K. Saxena Liwei Deng Yingwei Fei Jingzhu Hu Wei Luo Rajeev Ahuja 《Journal of Alloys and Compounds》2008,463(1-2):220-225
Mn+1AXn compounds have gathered huge momentum because of its exciting properties. In this paper we report the synthesis of ternary layered ceramic Cr2GeC, a 211 Mn+1AXn compound by hot-pressing. Scanning electron microscopy and X-ray diffraction have been employed to characterize the new synthesized phase. High-pressure compressibility of Cr2GeC were measured using diamond anvil cell and synchrotron radiation at room temperature up to 48 GPa. No phase transformation was observed in the experimental pressure range. The bulk modulus of Cr2GeC calculated using the Birch–Murnaghan equation of state is 169 ± 3 GPa, with K′ = 3.05 ± 0.15. 相似文献