Metrics cell-based

The currently perhaps most popular approach to cell-based partitioning in low-dimensional chemical spaces focuses on the so-called the BCUT metric... 

A diversity metric is a function to aid the quantification of the diversity of a set of compounds in some predefined chemical space. Diversity metrics fall into three main classes (1) Distance-based methods, which express diversity as a function of the pairwise molecular dissimilarities defined through measurement. (2) Cell-based methods, which define diversity in terms of occupancy of a finite number of cells that represent disjoint regions of chemical space. (3) Variance-based methods, which quantify diversity based on the degree of correlation between a compound s important features. 

The most intuitive cell-based diversity metric is simply the number of cells occupied by a design defined in (11) where 5, is one if the ith cell is occupied and zero if it is not, M the total number of cells. 

A second model due to Gaye 2. would appear to offer more promise it is based on the Kapoor-Frohberg model for the estimation of activities and assumes that both acidic and basic oxides are made up of symmetrical cells and these interact to form assym-metrical cells. The activities of the various oxides calculated for quaternary slags with this model are in excellent agreement with those determined experimentally. Values of for a given com-... 

In a recent classification study, scaffolds taken from natural products were subjected to a two-step analysis in order to identify a diverse set of natural product scaffolds with preferred ADME-properties." Molecular diversity analysis and selection of natural product scaffolds were carried out using cell-based partitioning and the BCUT metrics." To approximate ADME parameters, rule-of-five " calculations were carried out. A set of about 50 natural product scaffolds fulfilled the desired diversity and ADME criteria. ... 

Several diversity and space coverage measurements have also been considered in the combinatorial optimization process (15). Diversity and space coverage can be evaluated using a number of cell-based methods. These methods, implemented as diversity metrics (23), evaluate how much of the space occupied by the complete library is filled by the subset. For example, the cell-based fraction metric attempts to select one compound from each cell in order to cover as many cells as possible. However, owing to the combinatorial constraint, the objective to cover all occupied cells can seldom be achieved. The cell-based Chi metric attempts to level out the distribution so as to provide an even allocation of compounds to cells. Cell-based entropy and cell-based density metrics attempt to select more than one compound from the most populated cells, in order to respect the level of occupancy of each cell. The following metrics can be used as target functions in the combinatorial optimization process ... 

Cell-based fraction and cell-based density have consistently provided the most satisfactory results in our earlier work (15). The main difference between these two cell-based metrics relates to diversity and representativeness. Whereas cell-based fraction is designed to sample the complete library with... 

The pursuit of new lithium salts has been driven by the thermal instability of the current state-of-the-art lithium salts that were based on perfluorinated anions, and the thermal as well as chemical inertness has been taken as the main metric to evaluate any potential candidates to replace those salts, although, similar to the new solvent efforts, often the improvement in these properties comes at the price of other properties that are equally important for the operation of a lithium ion cell. 

Apart from being a constituent of rocket fuels, it is used to remove oxygen from boiler water to prevent the corrosion of the vessels. If, as some believe, hydrazine-based fuel cells eventually come into commercial use, demand will be enormous. Hydrazine hydrate production in noncommunist countries now stands at about 25000 metric tons per year, of which 17000 metric tons are used by the US with about 7000 metric tons taken by the space programs. 

In essence, we wish to follow the Gibbs entropy maximization procedure of Section 5.2 backward in time. Specifically, we seek to characterize the final stage of equilibration when effective local equilibrium has been achieved in each small cell n, but cell intensities are not yet equalized throughout the system. To make direct contact with Section 5.2, we shall temporarily revert to the entropy representation (Section 5.3), which generates a scalar product and metric geometry that is conformally equivalent to the (/-based metric... 

On the eve of the French Revolution, June 19, 1791, King Louis XVI of France gave his approval of the system. The next day, Louis tried to escape France but was arrested and jailed. A year later from his jail cell, Louis directed two engineers to make the measurements necessary to implement the metric system. Because of the French Revolution, it took six years to complete the required measurements. Finally, in June 1799 the Commission sur l unite de poids du Systeme Metrique decimal met and adopted the metric system. It was based on the gram as the unit of weight and the meter as the unit of length. All other measurements were to be derived from these units. The metric system was adopted For all people, for all time. ... 

There are numerous arithmetic functions that can be performed on single numbers. Useful examples are SQRT (square root), LOG (logarithm to the base 10), LN (natural log-arithm), EXP (exponential) and ABS (absolute value), for example =SQRT(A1+2 B1). A few functions have no number to operate on, such as ROW() which is the row number of a cell, COLUMN() the column number of a cell and PI() the number n. Trigono-metric functions operate on angles in radians, so be sure to convert if your original numbers are in degrees or cycles, for example =COS(PI()) gives a value of —1. 

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