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Image function

In the GE method the minimization of the transverse modes comes first and the maximization of the reaction mode second. We now describe a method that weights minimization and maximization equally. We assume the existence of an image function with the following properties.18 If the function to be optimized fix) has the following gradient and eigenvalues at x... [Pg.320]

The concept of image functions was introduced by C. M. Smith, Theor. Chim. Acta 74, 85 (1988). [Pg.320]

Hence, in the diagonal representation the gradient and Hessian are identical except for opposite sign in the lowest mode.19 Therefore, a first-order saddle point of the function coincides with a minimum of the image and we may determine the transition state by minimizing the image function. [Pg.321]

To minimize the image function we use a second-order method since in each iteration the Hessian is needed anyway to identify the mode to be inverted (the image mode). Line search methods cannot be used since it is impossible to calculate the image function itself when carrying out the line search. However, the trust region RSO minimization requires only gradient and Hessian information and may therefore be used. In the diagonal representation the step Eq. (5.8) becomes... [Pg.321]

We can now see the difference between the GE and TRIM methods. In the GE algorithm we first minimize the transverse modes and then maximize the reaction mode. In the TRIM method we minimize and maximize simultaneously by introducing an auxiliary function Eq. (6.21). The underlying idea of the GE method are lines connecting stationary points. The idea behind the TRIM method is an auxiliary function (the image function) whose minima coincide with the saddle points of the original function. [Pg.322]

An image function does not exist for all functions. It exists by definition for all quadratic functions. It also exists trivially for functions in one variable since an image is obtained simply by changing the sign of the function. In any case, the image concept is useful for formulating an algorithm. [Pg.322]

If the Laplace transform of a function /(/) is f s), then f(t) is the inverse Laplace transform of f(s). Although an integral inversion formula can be used to obtain the inverse Laplace transform, in most cases it proves to be too complicated. Instead, a transform table (1), is used to find the image function f f). For more complicated functions, approximate methods are available. In many cases the inverse of a ratio of two polynomials must be... [Pg.867]

Barton [26] suggested that one may use a Fourier transform formula to convert the intensity modulation into an image function, (r) ... [Pg.143]

The function F(ico)=F f(t) is the image function of f(t). After rearrangement of Eq. (6A.2), using the laws of the Laplace-Fourier transformation (cf. Appendix 4E), the measurable surface tension response Ay(t) of the system to the area disturbance Ain A(t) is obtained. [Pg.537]

A point light source is imaged onto the specimen by the objective and the transmitted light collected by the collector lens and detected by a broad-area detector in the case of reflection microscopy, the objective lens also serves simultaneously as a collector (see flgure Bl.18.10. The resolution is solely determined by the objective lens, because the collector has no imaging function and only collects the transmitted light. The... [Pg.1666]

The Thymus - Diagnostic Imaging, Functions, and Pathologic Anatomy... [Pg.253]

Because the image function /(z,z ) determines both the expected value and the covariance of the correlation image, it is important to understand its form. When the masks are based on a HURA of order u, and photons are collected from a detector area A of the same size and shape as the basis mask pattern (which contains v cells), the image function takes on a very simple form in the fully coded field of view [7] ... [Pg.375]

The functional activity of kidneys glued together was determined by excretory urography, radioisotopic renography, and magnetic resonance imaging function recovered 1—2 months postoperatively [462, 463]. [Pg.368]

Centrally Controlled Approach In this kind of approach phase 1, function Set-Partition, and phase 3, functions Set-Diff and Set-Union, are executed by a unique main process that splits completely the BDD representing the domain then the different images (function Img) are computed in parallel. [Pg.177]

Therefore, a well-engineered nanoplatform that offers both therapeutic and imaging functionalities could have important clinical value and be of great interest to the future development of combined cancer therapies. [Pg.366]


See other pages where Image function is mentioned: [Pg.163]    [Pg.12]    [Pg.137]    [Pg.17]    [Pg.321]    [Pg.321]    [Pg.322]    [Pg.234]    [Pg.266]    [Pg.350]    [Pg.284]    [Pg.397]    [Pg.20]    [Pg.185]    [Pg.522]    [Pg.522]    [Pg.374]    [Pg.110]    [Pg.175]    [Pg.319]    [Pg.121]    [Pg.58]    [Pg.2066]    [Pg.210]   
See also in sourсe #XX -- [ Pg.28 ]

See also in sourсe #XX -- [ Pg.20 ]




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Diffusion, functional imaging

Digital image analysis function

Function magnetic resonance imaging

Functional Imaging

Functional Imaging

Functional Imaging of Cellular Death

Functional Imaging of Rodent Lungs

Functional Invisible Imaging

Functional Magnetic Resonance Imaging fMRI), brain function study

Functional Other Imaging Technologies

Functional brain imaging

Functional imaging and

Functional imaging definitions

Functional imaging function

Functional imaging measurements

Functional imaging with magnetic resonance

Functional imaging with radioisotopes

Functional magnetic resonance imaging

Functional magnetic resonance imaging fMRI)

Image processing functions

Image spread function model

Image wave function

Imaging functional electron transfer

Imaging functionalized alkanethiols

Kidney, function, imaging

Magnetic Resonance Imaging , brain function study

Necrosis functional imaging

Protein function imaging

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