nowadays nmr spectroscopy becomes a powerful tool in chemistry because of the nmr chemical shifts. hartree–fock theory and the gauge-including atomic orbital (giao) methods are used in the calculation of 29si nmr chemical shifts of various silicate species in the silicate solution as initial components for zeolite synthesis both in gas and solution phase. calculations have been performed at geo...

Some types of medical and topographic imag­ ing device produce images in which the pixel values are "phase-wrapped", i.e., measured modulus a known scalar. Phase unwrapping can be viewed as the problem of inferring the integer number of relative shifts between each and every pair of neighboring pixels, subject to_ an a priori preference for smooth surfaces, and a zero curl constraint, which req...

We consider completely irrational nilflows on any nilmanifold of step at least 2. show that there exists a dense set smooth time-changes such time-change in this class which is not measurably trivial gives rise to mixing nilflow. This particular reproves and generalizes nilflow (of 2) the main result proved [3] for special Heisenberg (step nilflows, later generalized [58] arbitrary are isomorph...

Ecosystems often undergo abrupt regime shifts in response to gradual external changes. These shifts are theoretically understood as a regime switch between alternative stable states of the ecosystem dynamical response to smooth changes in external conditions. Usual models introduce nonlinearities in the macroscopic dynamics of the ecosystem that lead to different stable attractors among which t...

Introduction Proton resonance frequency (PRF)-shift MR thermometry is a promising tool for guiding thermal therapies in the treatment of liver tumors and heart arrhythmias, but is complicated by organ motion and respiration. To address motion, multi-baseline subtraction techniques have been proposed [1,2] that use a library of pre-treatment baseline images covering the cardiac and respiratory c...

VOL. 9, NO. 1, JANUARY 1998 Copyright © 1998 American Psychological Society 1 Abstract— If strategy shifts speed up performance, learning curves should show discontinuities where such shifts occur. Relatively smooth curves appear consistently in the literature, however. To explore this incongruity, we examined learning when multiple strategies were used. We plotted power law learning curves for...

Some types of medical and topographic imaging device produce images in which the pixel values are “phase-wrapped”, i.e., measured modulus a known scalar. Phase unwrapping can be viewed as the problem of inferring the number of shifts between each and every pair of neighboring pixels, subject to an a priori preference for smooth surfaces, and subject to a zero curl constraint, which requires tha...

Pseudo-splines constitute a new class of refinable functions with B-splines, interpolatory refinable functions and refinable functions with orthonormal shifts as special examples. Pseudo-splines were first introduced by Daubechies, Han, Ron and Shen in [Framelets: MRA-based constructions of wavelet frames, Appl. Comput. Harmon. Anal. 14(1) (2003), 1–46] and Selenick in [Smooth wavelet tight fra...

background and objectives: in this paper, a real life nurse scheduling model is described based on the conditions in iranian hospitals such as monthly shift rotation, consecutive morning and evening shifts and consecutive evening and night shift.   methods: the developed model considers both hospital constraints and nurses’ preferences. hospital constraints include assigning adequate qualified ...