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K, meaning

Type and designation Melting range (°C) Density (kg m ) Specific heat (J kg- K- ) Mean coefficient of thermal expansion (K- ) Thermal conductivity (W m K ) Electrical resistivity (fl m) Modulus of elasticity (G Pa)... [Pg.763]

The enormous value of K means that for all practical purposes this reaction goes to completion, consuming the limiting reactant, H+ or OH-. [Pg.394]

The method used here is called Forgy s method [25], This is one of the K-center or K-centroid methods, another well-known variant of which is MacQueen s K-means method [26]. Forgy s method involves the following steps. [Pg.78]

L. Kiernan, J.D. Mason and K. Warwick, Robust initialisation of Gaussian radial basis function networks using partitioned k-means clustering. Electron. Lett., 32 (1996) 671-672. [Pg.698]

This index is employed by both the k-means (MacQueen, 1967) and the isodata algorithms (Ball and Hall, 1965), which partition a set of data into k clusters. With the A -means algorithm, the number of clusters are prespecified, while the isodata algorithm uses various heuristics to identify an unconstrained number of clusters. [Pg.29]

The objective functions for both k-means clustering and the F-nearest neighbor heuristic given by Eqs. (20) and (21) use information only from the inputs. Because of this capacity to cluster data, local methods are particularly useful for data interpretation when the clusters can be assigned labels. [Pg.30]

A for building up arguments and 0 for building up functions on the outside. We must not only keep track of the number of steps and store the values for the next cycle in the v variables but must also keep track of which equation is currently acting on u, which equation is acting on y and which equation will act on v when we restart. We keep track of this information mnemonically in the addresses. Thus address (R,k) will mean restart with equation k (the equation for F ) and (i,j,k) means equation is acting on y, equation F. on u and equation will act on v when we restart. [Pg.244]

Beauchaine, T. P., Beauchaine, R. J. (2002). A comparison of maximum covariance and k-means cluster analysis in classifying cases into known taxon groups. Psychological Methods, 7, 245-261. [Pg.178]

B—The low value of K means that the equilibrium lies to the left. The equilibrium always lies away from the stronger acid and the stronger base. [Pg.237]

Table 1. Data and Results of Fit for Aqueous Solutions of uni-univalent electrolyte at 298.15°K - Mean Ionic Activity Coefficient Data... [Pg.76]

The most widely known algorithm for partitioning is the k means algorithm (Hartigan 1975). It uses pairwise distances between the objects, and requires the input of the desired number k of clusters. Internally, the k-means algorithm uses the so-called centroids (means) representing the center of each cluster. For example, a centroid c, of a cluster j = 1,..., k can be defined as the arithmetic mean vector of all objects of the corresponding cluster, i.e.,... [Pg.274]

Figure 6.8 shows clustering results for a synthetic data example in two dimensions with three groups. The plot symbols indicate the result of k-means clustering for k 2 (left), k 3 (middle), and k 4 (right). Here it is obvious that the choice k = 3 gave the best result since it directly corresponds to the visually evident data groups. [Pg.276]

Since the work function is very sensitive to contaminants, the most reliable measurements are done in ultrahigh vacuum conditions. From the determination of the electron work functions of Fe, Co, Ni, Cu, Au, and other metals in the presence of water adsorbed from the gas phase, it follows that water molecules are oriented with oxygen atoms toward the metal surface. The method is very sensitive to the presence of water. For example, upon adsorption of 3 x lO molecules of water per square centimeter of Co film (4% of a monolayer), the work function value is decreased by ca. 0.3 eV. However, these measurements were done at 77 K, meaning that adsorbed water was likely to be in a crystalline or amorphous ice form. Hence, the quoted results are of limited value to understanding the metal-water system in electrolyte solutions. [Pg.17]

The K-Means method can be rather efficient for a large number of objects, but requires a priori selection of the number of clusters K, and thus is less exploratory in nature than the HCA methods discussed earlier. In addition, its outcome depends on the initial selection of targets. As a result, one can do a smart selection of the initial targets based on their uniqueness in the data set, for example those objects with the highest Hotelling P value (Section 12.2.5) obtained from a PCA analysis of the data. [Pg.407]

Cluster Algorithm. The Forgy variety of k-means cluster analysis ( ) is chosen because of its speed for large data sets. Forgy k-means cluster analysis is an iterative process. In the first iteration observations are assigned to the nearest centroid. This defines the initial clusters. The composition of the observations in each cluster are then averaged to find approximate centroids. Let xk be the centroid vector for cluster k. with components xkj. for... [Pg.122]


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See also in sourсe #XX -- [ Pg.220 , Pg.221 ]




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