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61.
Sagar Chaki Edmund Clarke Natasha Sharygina Nishant Sinha 《Formal Methods in System Design》2008,32(3):235-266
This paper presents an automated and compositional procedure to solve the substitutability problem in the context of evolving software systems. Our solution contributes two
techniques for checking correctness of software upgrades: (1) a technique based on simultaneous use of over-and under-approximations
obtained via existential and universal abstractions; (2) a dynamic assume-guarantee reasoning algorithm—previously generated component assumptions are reused and altered on-the-fly to prove
or disprove the global safety properties on the updated system. When upgrades are found to be non-substitutable, our solution
generates constructive feedback to developers showing how to improve the components. The substitutability approach has been
implemented and validated in the ComFoRT reasoning framework, and we report encouraging results on an industrial benchmark.
This is an extended version of a paper, Dynamic Component Substitutability Analysis, published in the Proceedings of the Formal Methods 2005 Conference, Lecture Notes in Computer Science, vol. 3582, by the
same authors. This research was sponsored by the National Science Foundation under grant nos. CNS-0411152, CCF-0429120, CCR-0121547,
and CCR-0098072, the Semiconductor Research Corporation under grant no. TJ-1366, the US Army Research Office under grant no.
DAAD19-01-1-0485, the Office of Naval Research under grant no. N00014-01-1-0796, the ICAST project and the Predictable Assembly
from Certifiable Components (PACC) initiative at the Software Engineering Institute, Carnegie Mellon University. The views
and conclusions contained in this document are those of the authors and should not be interpreted as representing the official
policies, either expressed or implied, of any sponsoring institution, the US government or any other entity. 相似文献
62.
Creep experiments were conducted on ice crystals in compression to investigate the effects of boundary conditions on a single-slip system deformed in plane strain. Friction at the platens of the deformation apparatus introduces a bending moment which causes a variation in the amount of lattice rotation across the specimen. This is shown to occur in mechanically constrained crystals observed through plane polarized light. Relieving the constraints and minimizing friction at the ice-platen contact leads to the widening of the sample near the specimen-platen interface and the production of tails symmetrically disposed about the longitudinal axis of the deformed crystals. This is interpreted to originate from a bending moment in the opposite sense from that obtained in the constrained crystals, resulting from a progressive increase in slip displacement towards the platens where the segments of the slip plane become shorter. When the crystal ends were constrained but allowed to move sideways, a simple shear regime was established in which lattice slip was concentrated in the centre of the crystal. 相似文献
63.
Ranjan Prakash Mahto Santosh Kumar Choubey Arvind Sinha Rashmi Peraza-Vázquez Hernán Barde Chetan Peña-Delgado Adrián Roy Komal 《Microsystem Technologies》2022,28(11):2467-2485
Microsystem Technologies - In this paper synthesis of two wideband Metamaterial Cross Polarizer (MCPs) is proposed. The synthesis of proposed MCPs is done by using Binary Wind Driven Optimization... 相似文献
64.
Zahid Farzana Tanveer Awais Kuo Matthew M. Y. Sinha Roopak 《Journal of Intelligent Manufacturing》2022,33(6):1603-1638
Journal of Intelligent Manufacturing - The requirements engineering of Industrial Cyber-Physical Systems is extremely challenging due to large system sizes, component heterogeneity, involvement of... 相似文献
65.
Priyam Sinha Shruti Srivastava Nidhi Mishra Dhananjay Kumar Singh Suaib Luqman Debabrata Chanda 《Drug development and industrial pharmacy》2016,42(9):1434-1445
Purpose: To develop and optimize nanoemulsion (NE)-based emulgel (EG) formulation as a potential vehicle for topical delivery of tea tree oil (TTO).Methodology: Central composite design was adopted for optimizing the processing conditions for NE preparation by high energy emulsification method viz. surfactant concentration, co-surfactant concentration, and stirring speed. The optimized NE was developed into emulgel (EG) using pH sensitive polymer Carbopol 940 and triethanolamine as alkalizer. The prepared EG was evaluated for its pH, viscosity, and texture parameters, ex vivo permeation at 37?°C and stability. Antimicrobial evaluation of EG in comparison to conventional gel and pure TTO was also carried out against selected microbial strains.Results and discussion: Optimized NE had particle size and zeta potential of 16.23?±?0.411?nm and 36.11?±?1.234?mV, respectively. TEM analysis revealed the spherical shape of droplets. The pH of EG (5.57?±?0.05?) was found to be in accordance with the range of human skin pH. EG also illustrated efficient permeation (79.58?μL/cm2) and flux value (JSS) of 7.96?μL cm2/h through skin in 10?h. Viscosity and texture parameters, firmness (9.3?±?0.08?g), spreadability (2.26?±?0.06?mJ), extrudability (61.6?±?0.05?mJ), and adhesiveness (8.66?±?0.08?g) depict its suitability for topical application. Antimicrobial evaluation of EG with same amount of TTO as conventional gel revealed broader zones of growth inhibitions against all the selected microbial strains. Moreover, EG was also found to be nonirritant (PII 0.0833). These parameters were consistent over 90 d.Conclusion: TTO EG turned out to be a promising vehicle for the topical delivery of TTO with enhanced therapeutic efficacy. 相似文献
66.
This paper illustrates the applicability of neural networks in classifying events using Space Acceleration Measurement System (SAMS) data. Computer programs have been written in the MATLAB environment for the following purposes: automatic retrieval of SAMS data from NASA CDROM disks, computation of power spectral densities for SAMS data and construction of input patterns for the training of a multi-layer neural network (MNN). The MNN has been trained using the backpropagation learning algorithm and the SAMS data collected on the STS-50 Space Shuttle mission for three crew exercise events. It is found that the trained MNN is highly successful in classifying events. In addition, the performance of MNN is found to be better than that of the nearest neighbor classifier. 相似文献
67.
Sudipta N. Sinha Jan-Michael Frahm Marc Pollefeys Yakup Genc 《Machine Vision and Applications》2011,22(1):207-217
This paper describes novel implementations of the KLT feature tracking and SIFT feature extraction algorithms that run on
the graphics processing unit (GPU) and is suitable for video analysis in real-time vision systems. While significant acceleration
over standard CPU implementations is obtained by exploiting parallelism provided by modern programmable graphics hardware,
the CPU is freed up to run other computations in parallel. Our GPU-based KLT implementation tracks about a thousand features
in real-time at 30 Hz on 1,024 × 768 resolution video which is a 20 times improvement over the CPU. The GPU-based SIFT implementation
extracts about 800 features from 640 × 480 video at 10 Hz which is approximately 10 times faster than an optimized CPU implementation. 相似文献
68.
Localized operators, like Gabor wavelets and difference-of-gaussian filters, are considered useful tools for image representation. This is due to their ability to form a sparse code that can serve as a basis set for high-fidelity reconstruction of natural images. However, for many visual tasks, the more appropriate criterion of representational efficacy is recognition rather than reconstruction. It is unclear whether simple local features provide the stability necessary to subserve robust recognition of complex objects. In this article, we search the space of two-lobed differential operators for those that constitute a good representational code under recognition and discrimination criteria. We find that a novel operator, which we call the dissociated dipole, displays useful properties in this regard. We describe simple computational experiments to assess the merits of such dipoles relative to the more traditional local operators. The results suggest that nonlocal operators constitute a vocabulary that is stable across a range of image transformations. 相似文献
69.
SN Goodman 《Canadian Metallurgical Quarterly》1993,137(5):485-96; discussion 497-501
It is not generally appreciated that the p value, as conceived by R. A. Fisher, is not compatible with the Neyman-Pearson hypothesis test in which it has become embedded. The p value was meant to be a flexible inferential measure, whereas the hypothesis test was a rule for behavior, not inference. The combination of the two methods has led to a reinterpretation of the p value simultaneously as an "observed error rate" and as a measure of evidence. Both of these interpretations are problematic, and their combination has obscured the important differences between Neyman and Fisher on the nature of the scientific method and inhibited our understanding of the philosophic implications of the basic methods in use today. An analysis using another method promoted by Fisher, mathematical likelihood, shows that the p value substantially overstates the evidence against the null hypothesis. Likelihood makes clearer the distinction between error rates and inferential evidence and is a quantitative tool for expressing evidential strength that is more appropriate for the purposes of epidemiology than the p value. 相似文献
70.
The distribution coefficients of lead between copper and matte phases have been measured at 1405 and 1505 K and correlated
with lead and iron concentrations in metallic copper and matte. Experiments covered the ranges of 0.009 to 1.8 and 0 to 11
wt pct lead and iron in matte, respectively. Distribution coefficients of lead between copper and iron-free matte, at infinite
dilution of lead, have been determined to be 3.60 and 4.06 at 1505 and 1405 K, respectively. From the measured values of distribution
coefficients, the Raoultian activity coefficients of PbS in copper-saturated matte have been calculated. At the temperatures
and matte compositions investigated, activities of PbS deviate negatively from Temkin's ideality. At infinite dilution, the
following equation correlating the Raoultian activity coefficients of PbS,
, with matte composition and temperature has been obtained: In
, whereN
FeS
, is the mole fraction of FeS in the Cu2S-FeS-PbS matte. The present values of γ
PbS
o
must be used exclusively in conjunction with the following Gibbs free energy of formation: Pb(l) + 1/2S2(g) = PbS(l); ΔGℴ = −26730 + 12.20T (cal/mol).
M. NAGAMORI, Formerly Associate Professor of Metallurgy at The University of Utah, 相似文献