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Optimization defined

The areas of lead discovery and lead optimization define the field of medicinal chemistry. A medicinal chemist typically possesses formal training in synthetic organic chemistry because medicinal chemists need to continuously make new molecules for testing in some type of assay. Although their background may be in organic chemistry, medicinal... [Pg.24]

Model to be optimized (defined previously in the model declaration statement). [Pg.952]

ROC AUC was found to be an appropriate statistic to quantify the amount of optimism in the models. The optimism, defined here as the difference of the statistic... [Pg.100]

Points were taken from the range 0.8distributed origins that have been optimally defined for each fit. Shown in gray is the fully optimized basis b8 suitably scaled by 0.5. [Pg.444]

Efficiencies or optimums are ostensibly pursued in a utilitarian fashion, for their effectiveness in furthering the pursuit of our current goals. Efficiency cannot be said to be an intrinsic value if it is primarily an instrument for implementing the other values that define the context of its use (Alexander 2008, Kindle Locations 150-151). But when efficiency targets are set, or objective functions for optimization defined for a specific end in a specific context, they risk being undeservedly... [Pg.204]

Multi-objective optimization (MO) plays an important role in engineering design, management, and decision-making in general. Usually, a decision maker needs to make tradeoffs between disparate and conflicting objectives. The field of multiobjective optimization defines the art and science of making such decisions. [Pg.266]

Optimization of the system can be carried out by minimizing a cost function or maximizing economic potential EP defined by (see App. A)... [Pg.241]

Once the initial network structure has been defined, then loops, utility paths, and stream splits offer the degrees of freedom for manipulating network cost in multivariable optimization. During the optimization, there is no constraint that temperature differences should be larger than or that there should not be heat transfer... [Pg.397]

In practice, it is nontrivial to manually select the parameter values to obtain successful results. Moreover, it is not obvious how to measure the quality of the results. Therefore, a well defined performance measure and an efficient parameter optimization method are desired. [Pg.90]

Techniques have been developed within the CASSCF method to characterize the critical points on the excited-state PES. Analytic first and second derivatives mean that minima and saddle points can be located using traditional energy optimization procedures. More importantly, intersections can also be located using constrained minimization [42,43]. Of particular interest for the mechanism of a reaction is the minimum energy path (MEP), defined as the line followed by a classical particle with zero kinetic energy [44-46]. Such paths can be calculated using intrinsic reaction coordinate (IRC) techniques... [Pg.253]

Unfortunately, the approach of determining empirical potentials from equilibrium data is intrinsically limited, even if we assume complete knowledge of all equilibrium geometries and their energies. It is obvious that statistical potentials cannot define an energy scale, since multiplication of a potential by a positive, constant factor does not alter its global minimizers. But for the purpose of tertiary structure prediction by global optimization, this does not not matter. [Pg.215]

We use the sine series since the end points are set to satisfy exactly the three-point expansion [7]. The Fourier series with the pre-specified boundary conditions is complete. Therefore, the above expansion provides a trajectory that can be made exact. In addition to the parameters a, b and c (which are determined by Xq, Xi and X2) we also need to calculate an infinite number of Fourier coefficients - d, . In principle, the way to proceed is to plug the expression for X t) (equation (17)) into the expression for the action S as defined in equation (13), to compute the integral, and optimize the Onsager-Machlup action with respect to all of the path parameters. [Pg.271]

Once the quality of the dataset is defined, the next task is to improve it. Again, one has to remove outliers, find out and remove redundant objects (as they deliver no additional information), and finally, select the optimal subset of descriptors. [Pg.205]

The idea behind this approach is simple. First, we compose the characteristic vector from all the descriptors we can compute. Then, we define the maximum length of the optimal subset, i.e., the input vector we shall actually use during modeling. As is mentioned in Section 9.7, there is always some threshold beyond which an inaease in the dimensionality of the input vector decreases the predictive power of the model. Note that the correlation coefficient will always be improved with an increase in the input vector dimensionality. [Pg.218]

A molecular dynamics simulation nsnally starts with a molecular structure refined by geometry optimization, but wnthont atomic velocities. To completely describe the dynamics of a classical system con lain in g X atom s, yon m nsl define 6N variables. These correspond to ilX geometric coordinates (x, y, and /) and iSX variables for the velocities of each atom in the x, y, and /. directions. [Pg.73]

A transition structure is, of course, a maximum on the reaction pathway. One well-defined reaction path is the least energy or intrinsic reaction path (IRC). Quasi-Newton methods oscillate around the IRC path from one iteration to the next. Several researchers have proposed methods for obtaining the IRC path from the quasi-Newton optimization based on this observation. [Pg.154]


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See also in sourсe #XX -- [ Pg.58 ]




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