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Connectivity incidence matrix

Incidence matrix describes connections and bonds contains only 0 and L(bits) no bond types and bond orders no number of electrons... [Pg.39]

In the foregoing discussion the properties of the incidence matrix and the cycle matrix were illustrated in terms of a cyclic digraph, but the results on the ranks of these matrices actually hold true for any connected digraph with N vertices. For an undirected graph, M and C contain only 0 and 1 (sometimes referred to as binary matrices), mathematical relations of identical form are obtained except that modulo 2 arithmetic2 is used instead of ordinary arithmetic. The ranks of M and defined in terms of modulo 2 arithmetic are JV — 1 and C, as before, and Eqs. (10) and (11) are modified to read... [Pg.132]

The incidence matrix of such a graph specifies the connections of vertices and edges. For species J (figure 2) one has ... [Pg.12]

For instance, in the previous example of three connected pipes, flowmeters may be implemented at 3 instrumentation points. 3 constraints and 3 known variables are thus added to the structural model (Table 2). A rapid analysis of the graph (or incidence matrix)... [Pg.1323]

As each conserved state determines a domain, additional connection constraints can be found for various port types. For instance, a bond connected to one side of a 0-junction may be connected to a C-type storage port or a source port, as these ports do not violate the balance equation. However, in principle, one should be more careful when connecting an I-type, R-type, TF-type, or GY-typeport, because these ports cannot absorb the conserved state related to the flow. However, all domains with relative equilibrium-determining variables have a non-displayed balance for the reference node (this balance equation is dependent on the balance equations for the rest of the network and corresponds to the row that is omitted in an incidence matrix to turn it into a reduced incidence matfix of an electrical circuit, for example). This additional balance compensates for this flow, such that it is still possible to connect these ports without violating the balance equation. Note that the I-type port in principle is a connection to a GY-type port that connects to the storage in another domain. Some domains have absolute equilibrium-determining variables, like temperature and pressure, but since in most cases it is not practical to choose the absolute zero point as a reference, usually another reference state is chosen, such that these variables are treated as differences with respect to an arbitrary reference and an additional balance too. [Pg.50]

The incidence matrix that connects the numeric and geometric Kekule structures can be constructed using expression (3.1). It is called the weighted-hexagon-Kekule-structure incidence matrix and is denoted by HK. [Pg.59]

When restricting the graph G to arcs j g J , we obtain a subgraph (say) G° its reduced incidence matrix is of elements C j where n N and j g J . The subgraph is generally not connected it can even contain isolated nodes, not incident with any arc j g J°. Example ... [Pg.32]

If only mass is balanced we can formally admit a change in accumulation of mass in a node as a fictitious stream oriented towards die environment see Fig. 3-1. The conservation of mass is then expressed as Eq.(3.1.6) thus Cm = 0 where m is the (column) vector of mass flowrates and C the reduced incidence matrix of G, thus without row Hq. We assume G connected, hence C is of full row rank (3.1.5) thus N where M denotes generally the number of elements of set M. [Pg.55]

As a simplifying but plausible hypothesis, we can assume that the subgraph G [N-S, ] of reduced incidence matrix C is connected, thus C is of full row... [Pg.129]

Recall the observation after formula (8.2.16). In the inner double sum in (8.2.20), given s e Si the summation concerns only nodes n adjacent to node (splitter) s via some arc y e J,. It can happen that for some / > 1, none of the nodes s e is adjacent to any n Nj.. This, however, means that even before deleting the splitters, no node e Nj was connected by a path with any node n t Nj, bec se ft is just the arcs j J, (i e ) that have been deleted. Then also the graph [Ni, Ei ] contains at least two connected components, one of them being a subgraph of node set Nj see Fig. 8-7 and imagine a subset of rows ( t 0) empty in the columns J n Ei, and with just two nonnull elements in any column of Jii (incidence matrix of Gi,). Then the sum over in (8.2.20) equals zero and we must have, in case of... [Pg.219]

Let us consider the graph reduction. The corresponding matrix operation is summation of rows of the full incidence matrix over each subset of nodes constituting a connected component of G . The connected component containing the reference (environment) node is further not considered and the Af (= Af-1) rows of the submatrix (A/, A ) are thus sums of rows of (C, ) over the respective nodes of the remaining... [Pg.420]

We have introduced the incidence matrix A only for graphs that are not reduced to isolated nodes in the latter case the arc set is empty, and so is also the set of columns. According to Fig. A-3, the matrix can be decomposed into blocks that correspond each to one connected component G [N,(, J, ] where It 0 the void fields are of no interest. In what follows, let us thus assume that... [Pg.497]

Branched topologies as generated by the conditional Monte Carlo methods described in this section are most conveniently represented in matrix forms from graph theory [33, 53]. We name two of them the adjacency matrix A and the incidence matrix C (see Figure 9.22). They both describe connectivity. Note that in... [Pg.510]

We are interested in the development of an OFCD using bifurcated fibers.(70) In principle, they operate by first transmitting radiation from the light source through an optical fiber. The radiation exits at the distal end of the fiber where the reaction phase is located and where dye molecules susceptible to the presence of an analyte have been immobilized in a polymer matrix. The dye absorbs some of the incident radiation and, consequently, fluoresces. The fluorescence is collected by a second fiber connected in the same reaction phase, and the intensity exits at the other end and is measured by a detector. [Pg.197]

We showed in Section 2.3 that the real and imaginary parts of the electric susceptibility are connected by the dispersion relations (2.36) and (2.37). This followed as a consequence of the linear causal relation between the electric field and polarization together with the vanishing of x(<°) in the limit of infinite frequency to. We also stated that, in general, similar relations are expected to hold for any frequency-dependent function that connects an output with an input in a linear causal way. An example is the amplitude scattering matrix (4.75) the scattered field is linearly related to the incident field. Moreover, this relation must be causal the scattered field cannot precede in time the incident field that excited it. Therefore, the matrix elements should satisfy dispersion relations. In particular, this is true for the forward direction 6 = 0°. But 5(0°, to) does not have the required asymptotic behavior it is clear from the diffraction theory approximation (4.73) that for sufficiently large frequencies, 5(0°, to) is proportional to to2. Nevertheless, only minor fiddling with S makes it behave properly the function... [Pg.116]

In Chapter 4 a plane wave incident on a sphere was expanded in an infinite series of vector spherical harmonics as were the scattered and internal fields. Such expansions, however, are possible for arbitrary particles and incident fields. It is the scattered field that is of primary interest because from it various observable quantities can be obtained. Linearity of the Maxwell equations and the boundary conditions (3.7) implies that the coefficients of the scattered field are linearly related to those of the incident field. The linear transformation connecting these two sets of coefficients is called the T (for transition) matrix. I f the particle is spherical, then the T matrix is diagonal. [Pg.221]

Anthocyanins could act against carbon tetrachloride-induced lipoperoxi-dation. Anthocyanins could also reduce the incidences of fragility of capillaries, inhibit blood platelet aggregation, and strengthen the collagen matrix which is a component of the connective tissues [6]. [Pg.3]


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Connectivity matrix

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