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991.
We report the first direct measurements of the atomic dipole phase in the process of high-order harmonic generation. Differently from previously reported studies based on frequency chirp measurements, we use extreme ultraviolet interferometry as the most natural and direct way to measure phase shifts. Our approach has the important advantage of allowing us to investigate the effects associated to both the main quantum paths involved in the emission of a particular harmonic, thus offering a particularly clear and simple picture of the underlying electronic dynamics. 相似文献
992.
In this paper we are concerned with the following Neumann problem
993.
In this article, we consider a model check test for linear processes with infinite variance. As a test statistic, we employ the portmanteau test with trimmed residuals. It is shown that the limiting null distribution of the test is a chi-square distribution. Simulation results are provided for illustration. 相似文献
994.
Choung Min Ng 《Applied mathematics and computation》2010,217(7):3069-3087
In this paper, we consider a new class of bivariate negative binomial distributions having marginal distributions with different index parameters. This feature is useful in statistical modelling and simulation studies, where different marginal distributions and a specified correlation are required. This feature also makes it more flexible than the existing bivariate generalizations of the negative binomial distribution, which have a common index parameter in the marginal distributions. Various interesting properties, such as canonical expansions and quadrant dependence, are obtained. Potential application of the proposed class of bivariate negative binomial distributions, as a bivariate mixed Poisson distribution, and computer generation of samples are examined. Numerical examples as well as goodness-of-fit to simulated and real data are also given here in order to illustrate the application of this family of bivariate negative binomial distributions. 相似文献
995.
G Tang F Chen T C E Cheng C T Ng Z-L Chen 《The Journal of the Operational Research Society》2010,61(5):840-848
In this paper we consider a new transportation model, called the loader problem, which is frequently encountered by third-party logistics service providers in practice. It is a tactical staff-planning problem with the objective of minimizing the total labour cost of staffing a sufficient number of loaders on a given fleet of trucks that serve a given set of customer sites. We formulate the problem as an integer program and show that it is strongly NP-hard. We then consider two special cases of the loader problem that occur in certain practical situations, and propose polynomial and pseudo-polynomial time algorithms for solving these cases. We also propose a linear programming relaxation-based random rounding algorithm for the general problem and report the computational results of the algorithm. 相似文献
996.
Analysis of means (ANOM), similar to Shewhart control chart that exhibits individual mean effects on a graphical display, is an attractive alternative mean testing procedure for the analysis of variance (ANOVA). The procedure is primarily used to analyze experimental data from designs with only fixed effects. Recently introduced, the ANOM procedure based on the q‐distribution (ANOMQ procedure) generalizes the ANOM approach to random effects models. This article reveals that the application of ANOM and ANOMQ procedures in advanced designs such as hierarchically nested and split‐plot designs with fixed, random, and mixed effects enhances the data visualization aspect in graphical testing. Data from two real‐world experiments are used to illustrate the proposed procedure; furthermore, these experiments exhibit the ANOM procedures' visualization ability compared with ANOVA from the point of view of the practitioner. 相似文献
997.
Kaifa Wang Aijun Fan Angela Torres 《Nonlinear Analysis: Real World Applications》2010,11(4):3131-3138
Hepatitis B virus (HBV) infection is an important health problem worldwide. In this paper, we introduce an improved HBV model with standard incidence function and cytokine-mediated ‘cure’ based on empirical evidences. By carrying out a global analysis of the modified model and studying the stability of the equilibria, we show that infection-free equilibrium is globally asymptotically stable if the basic reproduction number of virus is less than one and, conversely, the infection equilibrium is globally asymptotically stable if the basic reproduction number of virus is greater than one. The study and information derived from this model and other related models may have an important impact on preventing mortality due to hepatitis B virus in the future. 相似文献
998.
Angela Vincenti Mohammad Reza Ahmadian Paolo Vannucci 《Journal of Global Optimization》2010,48(3):399-421
The genetic algorithm BIANCA, developed for design and optimisation of composite laminates, is a multi-population genetic
algorithm, capable to deal with unconstrained and constrained hard combinatorial optimisation problems in engineering. The
effectiveness and robustness of BIANCA rely on the great generality and richness in the representation of the information,
i.e. the structure of populations and individuals in BIANCA, and on the way the information is extensively exploited during
genetic operations. Moreover, we developed proper and original strategies to treat constrained optimisation problems through
the generalisation of penalisation methods. BIANCA can also treat constrained multi-objective problems based on the construction
of the Pareto frontier. Therefore, BIANCA allows us to approach very general design problems for composite laminates, but
also to make a step forward to the treatment of more general problems of optimisation of materials and structures. In this
paper, we describe specifically the case of optimal design of composite laminates, concerning both the theoretical formulation
and the numeric resolution. 相似文献
999.
Terence C. W. Poon Irene L. Ang Man‐Ki Law Kiwi Y. W. Chan Eddy W. Y. Ng Sai‐Ming Ngai Joseph J. Y. Sung Henry L. Y. Chan 《Electrophoresis》2010,31(10):1721-1730
ProteinChip surface‐enhanced laser desorption/ionization technology and magnetic beads‐based ClinProt system are commonly used for semi‐quantitative profiling of plasma proteome in biomarker discovery. Unfortunately, the proteins/peptides detected by MS are non‐recoverable. To obtain the protein identity of a MS peak, additional time‐consuming and material‐consuming purification steps have to be done. In this study, we developed a magnetic beads‐based proteomic fingerprinting method that allowed semi‐quantitative proteomic profiling and micropreparative purification of the profiled proteins in parallel. The use of different chromatographic magnetic beads allowed us to obtain different proteomic profiles, which were comparable to those obtained by the ProteinChip surface‐enhanced laser desorption/ionization technology. Our assays were semi‐quantitative. The normalized peak intensity was proportional to concentration measured by immunoassay. Both intra‐assay and inter‐assay coefficients of variation of the normalized peak intensities were in the range of 4–30%. Our method only required 2 μL of serum or plasma for generating enough proteins for semi‐quantitative profiling by MALDI‐TOF‐MS as well as for gel electrophoresis and subsequent protein identification. The protein peaks and corresponding gel spots could be easily matched by comparing their intensities and masses. Because of its high efficiency and reproducibility, our method has great potentials in clinical research, especially in biomarker discovery. 相似文献
1000.
An efficient and straightforward synthesis of furo[3,2-c]coumarins via the one-pot three-component condensation of aromatic aldehydes, 4-hydroxycoumarin and α-chloroketones in refluxing n-propanol is described. Pyridine or a mixture of AcOH and AcONH4 was used as a basic catalyst. 相似文献