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101.
Murray D. Burke 《Journal of multivariate analysis》1977,7(4):491-511
The recently developed strong approximation methods are discussed and applied to the problem of testing whether two independent multivariate samples come from the same population and whether the components of the observations are independent. The usual Cramér-von Mises statistic, as well as one based on the difference between the sum of the two multivariate EDF's and twice the product of the marginal EDF's of one, are studied. A fairly sensitive integral statistic is also discussed. Consistency and some asymptotic power properties are explored. Emphasis is placed on explication of the strong approximation methodology. 相似文献
102.
Summary In the proof of the main result of the original paper there is an error. Instead of repairing that proof to get just the original result, at the critical spot we improve the proof and obtain a much better result. In particular, we approximate the product-limit and empirical cumulative hazard processes by suitable copies of the corresponding limiting Gaussian processes with rates of approximation that on appropriate fixed half lines reduce to the rates of Komlós, Major and Tusnády for the uncensored empirical process. 相似文献
103.
An enantioselective synthesis of the tetrahydropyran “left-wing” ofthe ionophore X-14547A is described, wherein stereoselective 1,2-carbonyl additions and an oxapyronone-to-dihydropyran enolate Claisen rearrangement are key stereocontrol elements. 相似文献
104.
Paul J. Germann Roberta Aram A. Louis Odom Gerald Burke 《School science and mathematics》1996,96(4):192-201
The purpose of this study was to extend attempts to develop a research framework for encoding and analyzing students' responses to the tasks of asking questions, identifying variables, and formulating hypotheses, and to use the research framework to analyze and classify the responses of seventh grade students. A performance-based assessment instrument was used. The topic was heat and temperature. The responses of 364 seventh grade students were used to develop a framework for evaluating student written responses which allows researchers to classify student responses according to their general completeness and usefulness, and according to the manner in which responses were incomplete or not useful. Interrater reliability was 82%. Seventh grade students who reportedly have had instruction in the science processes did not perform well on this performance-based assessment. 相似文献
105.
A study of the reactivity of five thio-organic compounds with palladiumII ions has been made and one of them, 1-thioglycerol, selected for use as a spectrophotometric reagent for palladium. Its sensitivity is 0.01 μg of palladium/cm2 for log I0/I = 0.001. The sensitivity of the other four compounds is about the same. Beer's law is obeyed over the palladium concentration range of 0.5 to 9 ppm. The effects of pH, order of addition of reagents, temperature and diverse ions have been investigated. 相似文献
106.
Proton states in theN = 86 nuclei147Pm and149Eu populated in the (3He,d), (α,t) and (t, α) reactions
The (3He,d) and (α, t) reactions on targets of146Nd and148Sm have been studied, using beams of 24 MeV3He and 27 MeV4He from the McMaster University tandem van de Graaff accelerator. Also the (t, α) reaction on a target of148Sm has been studied, using 17 MeV tritons from the Los Alamos Scientific Laboratory tandem accelerator. The reaction products were analyzed with magnetic spectrographs. Information on thel-values was obtained from (3He,d) angular distributions and from ratios of (α,t) and (3He,d) cross sections. In each nucleus a severe fragmentation of the shell-model strength is found. In particular a total of 13(7)l=2 transitions and 6(6)l=0 transitions have been identified in147Pm(149Eu). The results are analyzed in terms of the spherical shell model, which accounts fairly well for the summed spectroscopic strengths. However, with the existence of the (t, α) data a more detailed investigation of the emptiness of individual levels observed in147Pm gives some indication that a deformed scheme might be more successful in describing these nuclei. 相似文献
107.
Burke CS McGaughey O Sabattié JM Barry H McEvoy AK McDonagh C MacCraith BD 《The Analyst》2005,130(1):41-45
This paper describes the development of a generic platform for enhanced, integrated optic sensors based on fluorescence detection. The platform employs a novel optical configuration in order to achieve enhanced performance and has inherent multianalyte detection capability. The sensor element comprises a multimode ridge waveguide that has been patterned with an analyte-sensitive fluorescent spot, which is excited directly using a LED. The platform was applied to the detection of gaseous oxygen as a proof of principle. The sol-gel-derived sensor spots were doped with an oxygen-sensitive fluorescent dichlororuthenium dye complex and intensity-based calibration data were generated from the oxygen-dependent waveguide output. The sensor achieved a LOD of 0.62% and a resolution of less than 0.96% gaseous oxygen, which compares favourably with a similar, recently reported system. This device highlights the combination of inexpensive rapid prototyping techniques and a dedicated sensor enhancement strategy that together facilitate the production of an effective prototype sensor platform. 相似文献
108.
Exact relations are derived between scaling to the high-density limit of density functional theory and taking Z to infinity for nondegenerate atoms. Gorling-Levy perturbation results are deduced for hydrogenic densities. The kinetic contribution to the correlation energy is also studied, and estimates given for its value for neutral atoms. Popular approximate functionals are tested against these benchmarks. 相似文献
109.
Linear response time-dependent density functional theory is used to study low-lying electronic continuum states of targets that can bind an extra electron. Exact formulas to extract scattering amplitudes from the susceptibility are derived in one dimension. A single-pole approximation for scattering phase shifts in three dimensions is shown to be more accurate than static exchange for singlet electron-He(+) scattering. 相似文献
110.
A new, vectorial approach to fast correlation attacks on binary memoryless combiners is proposed. Instead of individual input sequences or their linear combinations, the new attack is targeting subsets of input sequences as a whole thus exploiting the full correlation between the chosen subset and the output sequence. In particular, the set of all the input sequences can be chosen as the target. The attack is based on a novel iterative probabilistic algorithm which is also applicable to general memoryless combiners over finite fields or finite rings. To illustrate the effectiveness of the introduced approach, experimental results obtained for random balanced combining functions are presentedMost of this work was done while he was with Rome CryptoDesign Center, Gemplus, Italy 相似文献