Iterative threshold

Stem AS, Donoho DL, Hoch JC (2007) NMR data processing using iterative thresholding and minimum l(l)-norm reconstmction. J Magn Reson 188 295-300... 

G is a multiplier which is zero at locations where slip condition does not apply and is a sufficiently large number at the nodes where slip may occur. It is important to note that, when the shear stress at a wall exceeds the threshold of slip and the fluid slides over the solid surface, this may reduce the shearing to below the critical value resulting in a renewed stick. Therefore imposition of wall slip introduces a form of non-linearity into the flow model which should be handled via an iterative loop. The slip coefficient (i.e. /I in the Navier s slip condition given as Equation (3.59) is defined as... 

Set this threshold to a small positive constant (the default value is 10" ° Hartree). This threshold is used by HyperChem to ignore all two-electron repulsion integrals with an absolute value less than this value. This option controls the performance of the SCF iterations and the accuracy of the wave function and energies since it can decrease the number of calculated two-electron integrals. 

In the case of the threshold rules defined in this section, we must consider sequential iterations of deterministic rules. Also, the choice of spins that may change state is not random but is fixed by some random permutation of the sites on the lattice. Such rules may be shown to correspond to spin glasses in the zero-temperature limit. 

Intermlttency Manneville [mann80] showed that for the special case of a generic intermittency threshold in which the tangent point lies at the endpoint of the interval (in the case of a one dimensional iterative map of an interval to itself), the resulting chaotic dynamics has a power spectrum S f) 1/ (/(log/) ) for low /. Miracky, et. al. were able to modify the map to obtain an exact 1// behavior [mirack87]. Because the result depends on the fine-tuning of an external parameter, however, it does not so mucdi explain the generic appearance of flicker noise phenomena as beg the obvious question, why do systems typically sit at whatever... 

Step 5 If fe > 1, compute 8/ =/ —/ and compare 8/ with the convergence threshold, s. If 8(/ ) < s, then stop the iteration and declare that the optimal pulse has been obtained. 

Changes in the step bounds are based on ratiok. Its ideal value is 1.0 because then the model function PI agrees perfectly with the true function P. If the ratio is close to 1.0, we increase the step bounds if it is far from 1.0, we decrease them and if it is in between, no changes are made. To make this precise, we set two thresholds u and Z a ratio above u (typical value is 0.75) is close to 1.0, and a ratio below / (typical value is 0.25) is far from /. Then, the steps in PSLP iteration k are ... 

The iteration process terminates when the maximum difference in the elements of [Pg.211]

Multiple alignments of repeats are constructed in an iterative manner. The initial alignment is based on definitions from determined protein structures or else from the literature. In the initial database search step, a profile constructed from the multiple alignment is compared with a sequence database. Top scoring sequences are considered using complementary approaches such as PSI-BLAST and FASTA to provide the two thresholds minimum E value and minimum number of repeats per protein required. After one or two iterations, the final alignment and the thresholds are stored in the SMART database to allow the detection of repeats in any sequence. 

Reducing uncertainty is usually expensive. Therefore, an iterative process should be used to conduct the minimal amount of analyses that are necessary to characterize and reduce uncertainty to the point where an informed decision can be made. The point where a decision can be made with acceptable uncertainty will depend on the threshold of acceptability and threshold of unacceptability. ... 

The advantage of such an optimization scheme is that the SCF iterations do not converge to a non-stationary energy on the unconstrained potential energy surface that may only represent an energy minimum on the constrained potential energy surface, but to a true energy minimum, where the final local spin values—within a certain threshold—may differ from the ideal ones. 

PERTURBATION OF STARTING POINT THRESHOLD ON NORN OF THE STEP MAXIMUM NUMBER OF ITERATION... 

PROBLEM SHE STARTING POINT THRESHOLD ON FUNCTION NORM THRESHOLD ON STEP LEN6TH MAXIMUM NUMBER OF ITERATIONS... 

The iteration is stopped if the norm of the correction in the centroid and the distance between the best point and the centroid are both less than a small threshold EP. ... 

---