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Linear unique system conditioning

Thus, there are infinite (weD- and ill-) matrix condition numbers for the same linear system that depend on the system formulation. Conversely, there is one single standard form for each linear system and a unique system conditioning. [Pg.317]

If the source fingerprints, for each of n sources are known and the number of sources is less than or equal to the number of measured species (n < m), an estimate for the solution to the system of equations (3) can be obtained. If m > n, then the set of equations is overdetermined, and least-squares or linear programming techniques are used to solve for L. This is the basis of the chemical mass balance (CMB) method (20,21). If each source emits a particular species unique to it, then a very simple tracer technique can be used (5). Examples of commonly used tracers are lead and bromine from mobile sources, nickel from fuel oil, and sodium from sea salt. The condition that each source have a unique tracer species is not often met in practice. [Pg.379]

In order to apply the concepts of modern control theory to this problem it is necessary to linearize Equations 1-9 about some steady state. This steady state is found by setting the time derivatives to zero and solving the resulting system of non-linear algebraic equations, given a set of inputs Q, I., and Min In the vicinity of the chosen steady state, the solution thus obtained is unique. No attempts have been made to determine possible state multiplicities at other operating conditions. Table II lists inputs, state variables, and outputs at steady state. This particular steady state was actually observed by fialsetia (8). [Pg.189]

Once the appropriate dissolution conditions have been established, the method should be validated for linearity, accuracy, precision, specificity, and robustness/ruggedness. This section will discuss these parameters only in relation to issues unique to dissolution testing. All dissolution testing must be performed on a calibrated dissolution apparatus meeting the mechanical and system suitability standards specified in the appropriate compendia. [Pg.366]

Highly structured, 3-D nanoparticle-polymer nanocomposites possess unique magnetic, electronic, and optical properties that differ from individual entities, providing new systems for the creation of nanodevices and biosensors (Murray et al. 2000 Shipway et al. 2000). The choice of assembly interactions is a key issue in order to obtain complete control over the thermodynamics of the assembled system. The introduction of reversible hydrogen bonding and flexible linear polymers into the bricks and mortar concept gave rise to system formation in near-equilibrium conditions, providing well-defined stmctures. [Pg.148]

As noted, phospholipids as a class tend to be only partially soluble in oil or in water. In the presence of water, for example, dispersed phospholipids tend to form characteristic structures under predetermined conditions. Examples of these would be the linear pairing, inside and out, of cellular bilayers and, as an extension, the unique hollow spherical structures of free phospholipids called liposomes which have proved to be valuable as drug delivery systems. [Pg.244]

Monodisperse spheres are not only uniquely easy to characterize, but also very rarely encountered. Polymerization under carefully controlled conditions allows the preparation of the polystyrene latex shown in Figure 1.8. Latexes of this sort are used as standards for the size calibration of optical and electron micrographs (also see Section 1.5a.3). However, in the majority of colloidal systems, the particles are neither spherical nor monodisperse, but it is often useful to define convenient effective linear dimensions that are representative of the sizes and shapes of the particles. There are many ways of doing this, and whether they are appropriate or not depends on the use of such dimensions in practice. There are excellent books devoted to this topic (see, for example, Allen 1990) and, therefore, we consider only a few examples here for the purpose of illustration. [Pg.20]

It is important to recognize the unique relationship that exists between the responses to an impulse and step change in concentration. The derivative of the step response (Eq. 2.14) is identical to the impulse response (Eq. 2.4), and the integral of the impulse response is identical to the step response. This reciprocity is an important property of linear systems in general. The reader should now appreciate that under linear conditions, the time dependence of any concentration profile can be treated by adding the response functions for its component impulses. [Pg.22]

The regression vector, b, for each analyte is unique in an ideal noise-free linear system without component correlations (i.e., two or more analytes that vary together). Under realistic experimental conditions, however, only an approximation can be found for b under a set of experimental conditions. [Pg.335]

Linearized or asymptotic stability analysis examines the stability of a steady state to small perturbations from that state. For example, when heat generation is greater than heat removal (as at points A— and B+ in Fig. 19-4), the temperature will rise until the next stable steady-state temperature is reached (for A— it is A, for B+ it is C). In contrast, when heat generation is less than heat removal (as at points A+ and B— in Fig. 19-4), the temperature will fall to the next-lower stable steady-state temperature (for A+ and B— it is A). A similar analysis can be done around steady-state C, and the result indicates that A and C are stable steady states since small perturbations from the vicinity of these return the system to the corresponding stable points. Point B is an unstable steady state, since a small perturbation moves the system away to either A or C, depending on the direction of the perturbation. Similarly, at conditions where a unique steady state exists, this steady state is always stable for the adiabatic CSTR. Hence, for the adiabatic CSTR considered in Fig. 19-4, the slope condition dQH/dT > dQG/dT is a necessary and sufficient condition for asymptotic stability of a steady state. In general (e.g., for an externally cooled CSTR), however, the slope condition is a necessary but not a sufficient condition for stability i.e., violation of this condition leads to asymptotic instability, but its satisfaction does not ensure asymptotic stability. For example, in select reactor systems even... [Pg.12]

In this paper, an inverse problem for galvanic corrosion in two-dimensional Laplace s equation was studied. The considered problem deals with experimental measurements on electric potential, where due to lack of data, numerical integration is impossible. The problem is reduced to the determination of unknown complex coefficients of approximating functions, which are related to the known potential and unknown current density. By employing continuity of those functions along subdomain interfaces and using condition equations for known data leads to over-determined system of linear algebraic equations which are subjected to experimental errors. Reconstruction of current density is unique. The reconstruction contains one free additive parameter which does not affect current density. The method is useful in situations where limited data on electric potential are provided. [Pg.173]

Under these conditions system (9.1) still admits a unique steady state, but linear stability analysis shows that the latter is always stable (Goldbeter Dupont, 1990) this rules out the occurrence of sustained oscillations around a nonequilibrium unstable steady state. This result holds with previous studies of two-variable systems governed by polynomial kinetics these studies indicated that a nonlinearity higher than quadratic is needed for limit cycle oscillations in such systems (Tyson, 1973 Nicolis Prigogine, 1977). Thus, in system (9.1), it is essential for the development of Ca oscillations that the kinetics of pumping or activation be at least of the Michaelian type. Experimental data in fact indicate that these processes are characterized by positive cooperativity associated with values of the respective Hill coefficients well above unity, thus favouring the occurrence of oscillatory behaviour. [Pg.368]

We consider only the case that the kinetic terms Fi(p , Py, 4>) and F2ip , Py, 4>) depend linearly on the light intensity 4>- This covers both the photosensitive BZ reaction and the CDIMA reaction, see Sect. 13.7.1. The influence of the projected light is additive if /j and /2 are constants otherwise it is multiplicative. We assume that the system (13.157) has a unique steady state (Pn 4>), Py 4>)) which is stable. This requires that conditions (1.27) are satisfied, i.e., the trace of the Jacobian matrix... [Pg.411]

The determinant of a matrix A, Det(A), is useful in analyzing the uniqueness of a solution for a system of linear equations. Determinants arise in AR theory when computing conditions for critical CSTRs and DSRs. A number of properties of determinants are provided in the following text. Many of these properties are used in Chapters 6 and 7. [Pg.313]

This initial condition specifies the unique solution z t),yi(t) of the linear system (3.15). There now remains the first equation of (3.16) with boundary conditions IIiZi(O) = -Zjj(O), II,z( ) = 0 to define IIiZ(to). It can be shown that these conditions specify IIjz(to) uniquely (see [4]). [Pg.68]

We can uniquely define fi,(0) (i = 1,..., k) and d, (i = A + 1,..., m) from this system. Thus, IIiX (t) will be completely determined, and for the unspecified j3(t) the initial condition will be defined. This function is completely determined in the next step of the construction of the asymptotics during the solution of the equation for X2(0- The solvability condition for this equation provides a linear differential equation for fi(t)... [Pg.78]


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