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81.
V. Sadagopan H. C. Gatos K. Hechler E. Saur 《Zeitschrift für Physik A Hadrons and Nuclei》1969,225(3):231-236
Niobium nitride samples were irradiated with fast neutrons to a total dosage of 3.7×1019 NVT. The current carrying capacity of the samples before and after irradiation was determined. Significant enhancement of the current carrying capacity of the samples was found to result from irradiation (particularly in the 30–80 kGauss range) apparently due to neutron-induced defects acting as pinning centers for the fluxons. 相似文献
82.
Jane L. Harvill Priya Kohli Nalini Ravishanker 《Methodology and Computing in Applied Probability》2017,19(3):935-955
Accurate clustering of time series is a challenging problem for data arising from areas such as financial markets, biomedical studies, and environmental sciences, especially when some, or all, of the series exhibit nonlinearity and nonstationarity. When a subset of the series exhibits nonlinear characteristics, frequency domain clustering methods based on higher-order spectral properties, such as the bispectra or trispectra are useful. While these methods address nonlinearity, they rely on the assumption of series stationarity. We propose the Bispectral Smooth Localized Complex EXponential (BSLEX) approach for clustering nonlinear and nonstationary time series. BSLEX is an extension of the SLEX approach for linear, nonstationary series, and overcomes the challenges of both nonlinearity and nonstationarity through smooth partitions of the nonstationary time series into stationary subsets in a dyadic fashion. The performance of the BSLEX approach is illustrated via simulation where several nonstationary or nonlinear time series are clustered, as well as via accurate clustering of the records of 16 seismic events, eight of which are earthquakes and eight are explosions. We illustrate the utility of the approach by clustering S&P 100 financial returns. 相似文献
83.
The synthesis of enantiopure 2-C-methyl-d-erythritol-4-phosphate is disclosed. A 1,3-diol possessing a quaternary stereogenic centre, prepared stereoselectively from an acyclic tri-substituted alkene, has been utilized as a key intermediate. 相似文献
84.
We study characteristic Cauchy problems for the Korteweg–de Vries (KdV) equation ut = uux + uxxx , and the Kadomtsev–Petviashvili (KP) equation uyy =( uxxx + uux + ut ) x with holomorphic initial data possessing non-negative Taylor coefficients around the origin. For the KdV equation with initial value u (0, x )= u 0 ( x ), we show that there is no solution holomorphic in any neighborhood of ( t , x )=(0, 0) in C2 unless u 0 ( x )= a 0 + a 1 x . This also furnishes a nonexistence result for a class of y -independent solutions of the KP equation. We extend this to y -dependent cases by considering initial values given at y =0, u ( t , x , 0)= u 0 ( x , t ), uy ( t , x , 0)= u 1 ( x , t ), where the Taylor coefficients of u 0 and u 1 around t =0, x =0 are assumed non-negative. We prove that there is no holomorphic solution around the origin in C3 , unless u 0 and u 1 are polynomials of degree 2 or lower. MSC 2000: 35Q53, 35B30, 35C10. 相似文献
85.
Nalini Ravishanker J. R. M. Hosking Jaydip Mukhopadhyay 《Methodology and Computing in Applied Probability》2010,12(4):749-762
The problem of comparison of several multivariate time series via their spectral properties is discussed. A pairwise comparison
between two independent multivariate stationary time series via a likelihood ratio test based on the estimated cross-spectra
of the series yields a quasi-distance between the series. A hierarchical clustering algorithm is then employed to compare
several time series given the quasi-distance matrix. For use in situations where components of the multivariate time series
are measured in different units of scale, a modified quasi-distance based on a profile likelihood based estimation of the
scale parameter is described. The approach is illustrated using simulated data and data on daily temperatures and precipitations
at multiple locations. A comparison between hierarchical clustering based on the likelihood ratio test quasi-distance and
a quasi-distance described in Kakizawa et al. (J Am Stat Assoc 93:328–340, 1998) is interesting. 相似文献
86.
Nithyadharseni P. Reddy M. V. Nalini B. Saravanan P. Vinod V. T. P. Černík Miroslav Chowdari B. V. R. 《Journal of Solid State Electrochemistry》2016,20(6):1743-1751
Journal of Solid State Electrochemistry - In the present study, SnSb, SnSb/Fe, SnSb/Co, and SnSb/Ni alloy powders processed by co-precipitation were subjected to spark plasma-sintering... 相似文献
87.
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We develop NHPP models to characterize categorized event data, with application to modelling the discovery process for categorized software defects. Conditioning on the total number of defects, multivariate models are proposed for modelling the defects by type. A latent vector autoregressive structure is used to characterize dependencies among the different types. We show how Bayesian inference can be achieved via MCMC procedures, with a posterior prediction‐based L‐measure used for model selection. The results are illustrated for defects of different types found during the System Test phase of a large operating system software development project. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
90.
Kamal A Reddy KL Devaiah V Shankaraiah N Reddy GS Raghavan S 《Journal of combinatorial chemistry》2007,9(1):29-42
A versatile combinatorial approach was developed and utilized for the rapid synthesis of pyrrolo[2,1-c]-[1,4]benzodiazepine-5,11-dione (PBD-5,11-dione) libraries 10, 15, and 19 containing 210 compounds with varied substitutions in A, B, and C rings. The key aspect of the synthetic strategy includes Staudinger, intermolecular aza-Wittig reaction followed by imine reduction and base-mediated cyclative cleavage results in the formation of final resin-free compounds. This strategy provides a highly efficient and practical protocol for the parallel synthesis of PBD-5,11-diones on solid support. The modifications in the C-ring of the PBD scaffold produced three types of sublibraries. Reactions were monitored by FT-IR spectroscopy on the resin beads. Further, from a generated library of 210 compounds, 142 compounds have been selected and evaluated for in vitro activity against Mycobacterium tuberculosis, and some of these compounds have exhibited promising activity. 相似文献