Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Relationship between clustering and

It is easy to see that Cj,C2 is a hard partition of the classical set C. Thus, from these assignment rules we finally obtain the classical (or hard) hierarchy corresponding to the respective fuzzy hierarchy. Accordingly, the fuzzy divisive hierarchical clustering (FDHC) procedure may be used to obtain the optimal cluster structure of the data set and a hierarchical relationship between clusters and subclusters. The method is especially useful when the number of clusters is unknown. In most cases the number of clusters to be expected in the data set is unknown. [Pg.342]

The relationship between clustering and solute-solvent interaction forces may be explained thermodynamically. We begin with the triple product relationship... [Pg.63]

Four extensive reviews have highlighted the nature of the metal-metal bond and the use of polynuclear species as electron reservoirs, the relationship between clusters and metal surfaces, the mechanisms of cluster rearrangements, and complexes with multiple metal-metal bonds. ... [Pg.193]

Evidence of the appHcation of computers and expert systems to instmmental data interpretation is found in the new discipline of chemometrics (qv) where the relationship between data and information sought is explored as a problem of mathematics and statistics (7—10). One of the most useful insights provided by chemometrics is the realization that a cluster of measurements of quantities only remotely related to the actual information sought can be used in combination to determine the information desired by inference. Thus, for example, a combination of viscosity, boiling point, and specific gravity data can be used to a characterize the chemical composition of a mixture of solvents (11). The complexity of such a procedure is accommodated by performing a multivariate data analysis. [Pg.394]

Heteroatom fullerene-type clusters — The possibility of incorporation of hetero atoms into C clusters has excited the attention of both theoreticians and experimentalists since the earliest days of fullerene chemistry, particularly in view of the known stability and ubiquity of organic heterocycles. The structural relationship between Ceo and /3-rhombohedral boron has already been alluded to (p. 142). [Pg.288]

Repeat the studies, selecting intermediate temperature values using the relationships between Pq and J values for water shown in Table 3.2. For example, use Pb(WW) = 0.50 and J(WW) = 0.71 in Example 3.2. Compare the fx values with the Studies in Examples 3. land 3.2. A plot of each value from Studies in 3.1 and 3.2 will reveal the influence on these attributes with and without a density consideration. Also compare the average cluster sizes between these two groups of studies. How much difference is found in the fx values when water density is accounted for ... [Pg.51]

Fig. 5.6 Schematic representation of the relationship between clusters in (a) the [ Zr6B)Ch4] [NbeCliJ) structure ([001] projection on z = l/2) and (b) the [(ZrgBjClia] structure ([010] projection on y = 0). Fig. 5.6 Schematic representation of the relationship between clusters in (a) the [ Zr6B)Ch4] [NbeCliJ) structure ([001] projection on z = l/2) and (b) the [(ZrgBjClia] structure ([010] projection on y = 0).
Fig. 32. Relationship between Fa, and the dimensionless cluster size (Rla) for fractal clusters (D 2.5) of polystyrene latex in a simple shear flow. Data points are experimental results and the solid line is the theoretical prediction (Sonntag and Russel, 1986,1987a). Fig. 32. Relationship between Fa, and the dimensionless cluster size (Rla) for fractal clusters (D 2.5) of polystyrene latex in a simple shear flow. Data points are experimental results and the solid line is the theoretical prediction (Sonntag and Russel, 1986,1987a).
It is important to realize that statistical-overlap theory is not constrained by the contour of area A, which does not have to be rectangular as in earlier studies (in addition to previous references, see Davis, 1991 Martin, 1991,1992). In other words, Equations 3.2 and 3.3 should apply to the spaces WEG, FAN, and PAR. In this chapter, the number of clusters of randomly distributed circles in such areas is compared to the predictions of Equations 3.2 and 3.3a to assess the relationship between nP and practical peak capacity. Similarly, the number of peak maxima formed by randomly distributed bi-Gaussians in such areas is compared to the predictions of Equations 3.2 and 3.3b, and to Fig. 3.2, to make another assessment. [Pg.40]

Besides the applications of the electrophilicity index mentioned in the review article [40], following recent applications and developments have been observed, including relationship between basicity and nucleophilicity [64], 3D-quantitative structure activity analysis [65], Quantitative Structure-Toxicity Relationship (QSTR) [66], redox potential [67,68], Woodward-Hoffmann rules [69], Michael-type reactions [70], Sn2 reactions [71], multiphilic descriptions [72], etc. Molecular systems include silylenes [73], heterocyclohexanones [74], pyrido-di-indoles [65], bipyridine [75], aromatic and heterocyclic sulfonamides [76], substituted nitrenes and phosphi-nidenes [77], first-row transition metal ions [67], triruthenium ring core structures [78], benzhydryl derivatives [79], multivalent superatoms [80], nitrobenzodifuroxan [70], dialkylpyridinium ions [81], dioxins [82], arsenosugars and thioarsenicals [83], dynamic properties of clusters and nanostructures [84], porphyrin compounds [85-87], and so on. [Pg.189]

Although most of the reported gas-phase experiments do not investigate the temporal evolution of alcohol clusters explicitly, the frequency-domain spectral information can nevertheless be translated into the time domain, making use of some elementary and robust relationships between spectral and dynamical features [289]. According to this, the 10-fs period of the hydrogen-bonded O—H oscillator is modulated and damped by a series of other phenomena. Energy flow into doorway states is certainly slower than for aliphatic C—H bonds [290] but on a time scale of a few picoseconds, energy will nevertheless have... [Pg.41]

A biplot combines a score plot and a loading plot. It contains points for the objects and points (or arrows) for the variables, and can be an instructive display of PC A results however, the number of objects and the number of variables should not be too high. An appropriate scaling of the scores and the loadings is necessary, and mean-centering of the variables is useful. The biplot gives information about clustering of objects and of variables (therefore bi ), and about relationships between objects and variables. [Pg.67]

The relationship between boranes and metal-carbonyl clusters can be extended by considering the compound Fe5(CO)i5C, which has the square-based pyramidal structure shown in Fig. 13, with the carbide carbon atom just below the center of the Fe square, clearly contributing all its valence shell electrons to the cluster 24). The metal-carbonyl residue FeB(CO)i4 formally left by removal of this carbon as has the nido structure appropriate for a cluster with 5 skeletal atoms and seven skeletal bond pairs. [Pg.19]

Figure 9 shows a relationship between JTl and JTsc,ov for all salts. Any relationship between them is not clear on the whole. However, inversely proportional relationships are slightly observed for each group of barium salts and sodium salts. Considering such experimental result, it may be supposed that the adhesion force of remained clusters is controlled by more strong factors, such as a crack of the surface of nucleation agent occurred by the solid inclusion during the activation treatment. [Pg.407]

Combining Eq. (41) with (40) and using nv = 4irE3/(3wv) give the desired relationship between AF and R for clusters of any size. [Pg.27]

Cluster models of mixed oxide catalysts and of relationships between solid and solution catalysts... [Pg.115]

Classen JB, Classen DC. Clustering of cases of insulin dependent diabetes (IDDM) occurring three years after Hemophilus influenza B (HiB) immunization support causal relationship between immunization and IDDM. Autoimmunity 2002 35(4) 247-53. [Pg.671]


See other pages where Relationship between clustering and is mentioned: [Pg.186]    [Pg.349]    [Pg.186]    [Pg.349]    [Pg.300]    [Pg.364]    [Pg.683]    [Pg.176]    [Pg.102]    [Pg.191]    [Pg.350]    [Pg.819]    [Pg.149]    [Pg.449]    [Pg.43]    [Pg.404]    [Pg.111]    [Pg.133]    [Pg.351]    [Pg.67]    [Pg.402]    [Pg.280]    [Pg.158]    [Pg.164]    [Pg.316]    [Pg.698]    [Pg.146]    [Pg.179]    [Pg.412]    [Pg.39]    [Pg.187]    [Pg.138]    [Pg.24]    [Pg.291]    [Pg.358]   


SEARCH



© 2024 chempedia.info