Results 251 to 260 of about 1,199,939 (304)

Cross-Sectional Time Series Designs: A General Transformation Approach

Multivariate Behavioral Research, 1991
Cross-sectional time series designs assess the generalizability of intervention effects across different units. The general transformation approach to time series analysis was proposed by Velicer and McDonald (1984) to avoid the model identification step.
W F, Velicer, R P, McDonald
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Transformation of Scattering Cross Sections

Journal of Applied Physics, 1954
A simple method is presented for the calculation of the transformation matrices between the Legendre polynomial expansion coefficients of the scattering cross section in the laboratory and center-of-mass systems. Approximate expressions for the matrices are given.
Zweifel, P. F., Hurwitz, H. jun.
openaire   +1 more source

Full-Frame Transform Coding of Cross-Sectional Images

SPIE Proceedings, 1989
Image compression algorithms based on full-frame discrete transforms completely eliminate the artifacts generated by block quantization techniques. Previously, we have shown that full-frame compression using an adaptive two-dimensional bit-allocation table is capable of achieving compression ratios as high as 10:1 to 20:1, while maintaining excellent ...
K. K. Chan, Shyh-Liang Lou, H. K. Huang
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Rigorous determination of cross sections via complex transformations

International Journal of Quantum Chemistry, 2009
General formulas useful in the context of probability-amplitude calculations are given in terms of the appropriately deformed resolvent expressions. It is proven that the formulation based on the skew inner projections leads to a series of approximations for the dilated resolvent, convergent in the limit to the exact result.
Erkki Brändas, Piotr Froelich
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Analysis of Rosen piezoelectric transformers with a varying cross-section

IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control, 2008
We study the effects of a varying cross-section on the performance of Rosen piezoelectric transformers operating with length extensional modes of rods. A theoretical analysis is performed using an extended version of a one-dimensional model developed in a previous paper. Numerical results based on the theoretical analysis are presented.
H, Xue, J, Yang, Y, Hu
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Transformation of waves in beams of variable cross section

Soviet Journal of Quantum Electronics, 1990
An investigation is made of the feasibility of improving the characteristics of a stimulated scattering amplifier and of a hypersonic phase-conjugating mirror by the use of beams with variable cross sections. It is shown that in the process of amplification due to stimulated scattering of an external signal there is an infinite set of geometric ...
A P Vasin, V F Efimkov, I G Zubarev, A R Petrukhin, V B Sobolev   +4 more
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Cross-sectional area measurement in collapsed tubes using the transformer principle

Medical & Biological Engineering & Computing, 1989
To avoid the necessity for intraluminal catheters as used with the axial impedance method of measuring the cross-sectional area of flexible tubes independently of their shape, while retaining the advantage of an immediate electrical output, an electromagnetic method was tested.
C D, Bertram, C, Ribreau
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Ion collision cross section measurements in Fourier transform-based mass analyzers

The Analyst, 2016
High-vacuum ion collision cross section (CCS) measurements in Fourier transform mass analyzers.
Dayu, Li, Yang, Tang, Wei, Xu
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Form-Invariance of Maxwell's Equations in Waveguide Cross-Section Transformations

Electromagnetics, 2009
Abstract We present a novel coordinate transformation technique that controls the propagation of waves inside a waveguide, such that the waveguide behaves as if it is a “reshaped” waveguide. In this technique, the spatial domain of the waveguide is mapped to that of its reshaped equivalent, yielding an anisotropic medium inside the waveguide.
Ozlem Ozgun, Mustafa Kuzuoglu
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Naturally Ordered Transformation Semigroups Preserving an Equivalence Relation and a Cross-section

Algebra Colloquium, 2011
The paper is concerned with the so-called natural order on the semigroup [Formula: see text], where [Formula: see text] is the full transformation semigroup on a set X, E is a non-trivial equivalence on X and R is a cross-section of the partition X/E induced by E. We determine when two elements of TE(X,R) are related under this order, find elements of
Sun, Lei, Deng, Weina, Pei, Huisheng
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