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System condition number

The matrix condition number of a system in its standard form is called the system conditioning or system condition number. [Pg.318]

Sys temCondi tioning calculates the system condition number. [Pg.336]

Affinity values aie obtained by substituting concentiation foi activity in equation 4 foi the dye and, wheie appropriate, other ions in the system. A number of equations are used depending on the dye—fiber combination (6). An alternative term used is the substantivity ratio which is simply the partition between the concentration of dye in the fiber and dyebath phases. The values obtained are specific to a particular dye—fiber combination, are insensitive to hquor ratios, but sensitive to all other dyebath variables. If these limitations are understood, substantivity ratios are a useful measure of dyeing characteristics under specific appHcation conditions. [Pg.350]

Whereas Freeman and Lewis reported the first comprehensive analysis of hydroxymethylation of phenol, they were not the last to study this system. A number of reports issued since their work have confirmed the general trends that they discovered while differing in some of the relative rates observed [80,84-99], Gardziella et al. have summarized a number of these reports ([18], pp. 29-35). In addition to providing new data under a variety of conditions, the other studies have improved on the accuracy of Freeman and Lewis, provided activation parameters, and added new methodologies for measuring product development [97-99],... [Pg.901]

The matrix A is known as the preconditioner and has to be chosen such that the condition number of the transformed linear system is smaller than that of the original system. [Pg.167]

The condition number of a matrix A is intimately connected with the sensitivity of the solution of the linear system of equations A x = b. When solving this equation, the error in the solution can be magnified by an amount as large as cortd A) times the norm of the error in A and b due to the presence of the error in the data. [Pg.142]

If however, matrix A is reasonably well-conditioned at the optimum, A could easily be ill-conditioned when the parameters are away from their optimal values. This is quite often the case in parameter estimation and it is particularly true for highly nonlinear systems. In such cases, we would like to have the means to move the parameters estimates from the initial guess to the optimum even if the condition number of matrix A is excessively high for these initial iterations. [Pg.143]

In the selection of an appropriate cell culture system, a number of criteria must be considered (Table 3). These include not only the characteristics of the cell type but also the controllable parameters of the complete transport system such as the permeants, the filter properties, and the assay conditions. In general, most transport experiments employ the experimental design shown schematically in Figure 4 with modifications as discussed below. Typically, the desired cell is seeded onto some sort of semipermeable filter support and allowed to reach confluence. The filter containing the cell monolayer separates the donor and receiver... [Pg.241]

The desired independence between the variables of the different analytical signals corresponds directly with the selectivity of the analytical system (Kaiser [1972] Danzer [2001], and Sect. 7.3). In case of multivariate calibration, the selectivity is characterized by means of the condition number... [Pg.185]

Equation (6.79) is valid for exactly determined systems (m = n). In case of overdetermined systems, m > n, the condition number is given by... [Pg.185]

If systems are well-conditioned the selectivity is expressed by condition numbers close to 1. [Pg.185]

Selectivity. In general, selectivity of analytical multicomponent systems can be expressed qualitatively (Vessman et al. [2001]) and estimated quantitatively according to a statement of Kaiser [1972] and advanced models (Danzer [2001]). In multivariate calibration, selectivity is mostly quantified by the condition number see Eqs. (6.80)-(6.82). Unfortunately, the condition number does not consider the concentrations of the species and gives therefore only an aid to orientation of maximum expectable analytical errors. Inclusion of the concentrations of calibration standards into selectivity models makes it possible to derive multivariate limits of detection. [Pg.188]

One of our main interests is to describe quark matter at the interior of a compact star since this is one of the possibilities to find color superconducting matter in nature. It is therefore important to consider electrically and color neutral2 matter in /3-equilibrium. In addition to the quarks we also allow for the presence of leptons, especially electrons muons. As we consider stars older than a few minutes, when neutrinos can freely leave the system, lepton number is not conserved. The conditions for charge neutrality read... [Pg.196]

The minimum singular value is a measure of the invertibility of the system and therefore represents a measure of the potential problems of the system under feedback control. The condition number reflects the sensitivity of the system under uncertainties in process parameters and modelling errors. These parameters provide a qualitative assessment of the dynamic properties of a... [Pg.62]

Nbf is the number of degrees of freedom, Nc is the number of components, and Np is the number of phases in the system. The number of degrees of freedom represents the number of independent variables that must be specified in order to fix the condition of the system. For example, the Gibbs phase rule specifies that a two-component, two-phase system has two degrees of freedom. If temperature and pressure are selected as the specified variables, then all other intensive variables—in particular, the composition of each of the two phases—are fixed, and solubility diagrams of the type shown for a hypothetical mixture of R and S in Fig. 1 can be constructed. [Pg.196]

The significance of CPSC is that this is the additional head the pumps must produce in order to get the fluid up over the GP at the control point with a minimum terrain clearance. This, of course, results in the HGL terminating at mp-105 at a much higher head than the specified 1600-ft terminal end head. This excess head, also tabulated in Table n, must be wasted or burned off as friction. This can be accomplished in a number of ways, such as introducing an orifice plate, introducing a valve, or decreasing the pipe diameter. Depending on specific pipeline system conditions and economics, any of these alternatives may be desirable. [Pg.273]

Differences in rates of transformation and/or utilization between the two systems are possibly due to a) constant input vs. single input of p-coumaric acid and nutrient solution, b) aerobic (open system) vs. more anaerobic (closed system) conditions, c) little chance for accumulation of transformation products and/or toxic microbial byproducts (constant flushing of system) vs. potential build up of transformation products and/or toxic microbial byproducts (closed system), d) different microbial communities both in terms of species (air-dried soil vs. autoclaved-inoculated soil) and numbers (10s vs. 108), and e) input of p-coumaric acid (53 pg/mL/h or 187 pg/h vs. 58 pg/mL one time addition) added to different amounts of soil (60 g of soil for the flow-through system vs. 1 g of soil for the test tube system). [Pg.78]

The resolution achievable by a system depends upon the number of theoretical plates generated by that system and upon the selectivity of the system. The number of theoretical plates can be varied widely with separation path length, flow conditions, field strength, etc., and is thus highly variable. However, selectivity 1s a more Intrinsic property of the fractionation method and serves as a basis of comparison of the different systems. [Pg.220]

Smaller number of experiments Computational fluid dynamics limit the range of relevant process parameters and thereby reduce the number of experiments required. In particular, it is possible to identify critical system conditions and to eliminate them from the experiment in advance. This results in considerable time and cost savings. [Pg.139]

Experience has shown the covariance matrix 0rm to be conspicuously different when the same problem was treated by either the rs-method (without enforcing the first and second moment conditions) or any of the r0-derived methods. For the former method the errors of the coordinates were much less correlated. This, as well as the better condition number of the normal equation system, is no doubt a... [Pg.103]

The new coefficient matrix is symmetric as M lA can be written as M 1/2AM 1/Z. Preconditioning aims to produce a more clustered eigenvalue structure for M A and/or lower condition number than for A to improve the relevant convergence ratio however, preconditioning also adds to the computational effort by requiring that a linear system involving M (namely, Mz = r) be solved at every step. Thus, it is essential for efficiency of the method that M be factored very rapidly in relation to the original A. This can be achieved, for example, if M is a sparse component of the dense A. Whereas the solution of an n X n dense linear system requires order of 3 operations, the work for sparse systems can be as low as order n.13-14... [Pg.33]

Commentary Steady state conditions are distinguished from equilibrium by the occurrence of processes in which inputs and outputs for the systems remain in balance, so that no net alterations occur within the system. However, those processes do cause alterations in the surroundings. For example, in the passage of a constant electric current through a wire, which is the system, the number of electrons in any section of the wire... [Pg.6]

Stiegel and Shah34 measured the liquid-phase axial dispersion coefficient in a packed rectangular column. Some details of system conditions used in this study have been described earlier, in Sec. 7-3. The axial dispersion coefficient and the liquid-phase Peclet number were correlated to the gas and liquid Reynolds numbers by the expressions... [Pg.249]


See other pages where System condition number is mentioned: [Pg.1972]    [Pg.206]    [Pg.142]    [Pg.641]    [Pg.196]    [Pg.167]    [Pg.159]    [Pg.113]    [Pg.447]    [Pg.379]    [Pg.63]    [Pg.63]    [Pg.63]    [Pg.205]    [Pg.147]    [Pg.142]    [Pg.139]    [Pg.633]    [Pg.716]    [Pg.206]    [Pg.97]    [Pg.57]    [Pg.186]    [Pg.254]    [Pg.181]    [Pg.281]   
See also in sourсe #XX -- [ Pg.318 , Pg.336 ]




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