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Non-linear equation

Using the formulas listed above, it is possible to reach the non-linear equation... [Pg.266]

Dennis J E and Schnabel R B 1983 Numerical Methods for Unconstrained Optimization and Non-linear Equations (Englewood Cliffs, NJ Prentice-Hall)... [Pg.2355]

Then one can apply Newtons method to the necessaiy conditions for optimahty, which are a set of simultaneous (non)linear equations. The Newton equations one would write are... [Pg.486]

These non-linear equations can be embedded into the refinery s linear program (LP) to achieve compliance and optimize the gasoline blend. The key FCC gasoline components that influence RFG are ... [Pg.315]

Hie quasi steady state approximation can be conveniently applied to equations 19 to 21, without any significant loss of accuracy, due to tlie high reactivity of tlie reacting species in aqueous solution. Hms, the system of ordinary differential equations is readily reduced to a system of algebraic non linear equations. [Pg.385]

Combining equations (7.4-24)-(7.4-26) gives a system of non-linear equations that can be solved using iterative techniques. Savings in equipment costs as compared to initial guesses are approximately 30 %. The real savings will be lower because the optimal choices for equipment units are usually not available on the chemical equipment market. The standard sizes greater but nearest to the optimal sizes will be selected. The total cost for the standard equipment is very close to the minimum found. Robinson and Loonkar (1972) extended their procedure for multiproduct batch plants. [Pg.480]

The kinetic equations describing these four steps have been summarized and discussed in the earlier paper and elsewhere (1,5). They can be combined with conservation laws to yield the following non-linear equations that describe the transient behavior of the reactor. In these equations the units of the state variables T, M, and I are mols/liter, while W is in grams/liter. The quantity A (also mols/liter) represents that portion of the total polymer that is unassociated — i.e. reactive. [Pg.188]

In this study the linearized equations were used to determine the control strategy, but the non-linear equations were used to test this strategy. For small deviations from the steady state (5% or less) there is very little difference between the responses of the non-linear and the linearized system. [Pg.190]

The non-linear equations 21 and equations 35-38 can be solved iteratively to give directly, the instantaneous efficiencies and the the ratios of rate constants (kx/kp), (ktc/kp2) and (ktc /kp2). The values obtained for the rate constants have been summarized in Table III and in Figures 3 and 6. The results from the calculations show a small difference (ie less than 1 ) betwen ktc and ktc. Therefore, for all practical purposes they can be considered equal... [Pg.213]

K, K 2, and K3 are the equilibrium constants for the formation of hydrogen molecule, H2S and H20 gases respectively from the atomic elements. The equations for each of the atomic elements form simultaneous non-linear equations which can be solved for example by Newton s method, starting with very small initial values of the number of each atomic and molecular species, i.e. 10-8. [Pg.95]

Six constants are involved in these non linear equations, which calls for either a nonlinear regression or the solution of six nonlinear equations at selected data points. [Pg.726]

J.E.Dennis, R.B. Schnabel Numerical methods for unconstrained optimization and non-linear equations, Prentice Hall Series in computational mathematics, New York, (NY, USA), 1983... [Pg.168]

System of implicit non-linear equations the Newton-Raphson method... [Pg.142]

The Newton-Raphson method consists in solving simultaneously the conservation and mass action equations. Because of its simplicity and rather fast convergence, it is well-fitted to sets of non-linear equations in several unknowns, as described in Chapter 3. [Pg.320]

IVIVCs can be divided into non-quantitative and quantitative. In non-quantitative correlations the two variables are not related to each other via a mathematical relationship. A characteristic example is the rank-order correlation that was popular in the 1970s (10-15). In quantitative correlations the in vitro variable correlates with the in vivo variable via a linear or a non-linear equation. A quantitative IVIVC can be established, with or without the framework of a model, by using estimated values of characteristic parameters of the in vitro dissolution process and estimated values of the characteristic parameters of the in vivo arrival-in-bloodstream... [Pg.232]

The Newton-Raphson algorithm is further developed into a fairly generally applicable tool for the solving of sets of non-linear equations. [Pg.3]

The relative ease of solving the system of non-linear equations for rather complex equilibrium problems, as indicated by the shortness of the function NewtonRaphson. m and by the inconsequentiality of poor initial guesses, is misleading. As we will see shortly, this statement is particularly pertinent to cases of general systems of m equations with m parameters. Solving systems of equations is a common task and we give a short introduction. To start with, we investigate the simple case of one equation with one parameter. [Pg.69]

As we have demonstrated, systems of non-linear equations with several unknowns are difficult to resolve. The task of developing a general program that can cope with all eventualities is huge. We are only offering a very minimal program that specifically analyses the system of equations (3.70). Instead of the two variables x and y we use a vector x with two elements similarly, we use a vector z instead of zl and z2. The elements of the required Jacobian J can be given explicitly (see Two Equations. m). The shift vector delta x is calculated as in equation (3.38). [Pg.74]

The Excel Solver Add-In is a very powerful tool. We have already used it to solve systems of non-linear equation, see Chapters 3.3.3 Solving Complex... [Pg.207]

Equilibria and 3.3.4 Solmng Non-Linear Equations. The Solver includes optimisation as one of the options. Its main application, within this chapter on data analysis, is data fitting, based on the minimisation of sum of squares. [Pg.207]

In general, the formulation of the problem of vapor-liquid equilibria in these systems is not difficult. One has the mass balances, dissociation equilibria in the solution, the equation of electroneutrality and the expressions for the vapor-liquid equilibrium of each molecular species (equality of activities). The result is a system of non-linear equations which must be solved. The main thermodynamic problem is the relation of the activities of the species to be measurable properties, such as pressure and composition. In order to do this a model is needed and the parameters in the model are usually obtained from experimental data on the mixtures involved. Calculations of this type are well-known in geological systems O) where the vapor-liquid equilibria are usually neglected. [Pg.49]

Newton s method is used for non-linear equations. The program requires the user to compile program modules and then link them to the libraries provided. [Pg.303]

To enable solution of the set of equations, the number of unknown variables and the number of (non-linear) equations should be equal. The variables are x, (> (), Ni, Tand E, so in case of n components and K, + K2 discretization points we have (Kj + /Cj + U (2 -f 2) unknowns. At each discretization point, eq. (4) has been used for components 1 to — 1, whereas for component n this equation has been replaced by... [Pg.5]

The system of non-linear equations has been solved by the multidimensional Newton-Raphson technique which involves the successive solution of a linear system of equations ... [Pg.5]

Wentworth, W.E. (1965a), Rigorous Least Suqares Adjustment Application to Some Non-Linear Equations I., J. Chem. Educ., 42, 96-103. [Pg.427]

SC) CAS-SDCI may be viewed as a set of d equations to be solved simultaneously (actually, the implementation of the method is a recursive diagonalization process). In contrast, ec-CCSD implies a unique diagonalization and a further resolution of a rather small set of non-linear equations. [Pg.76]

Intuitively, the correct application of restraints and constraints to electron density should improve the phases. To quantify this notion, it is useful, though unconventional, to proceed as if we are solving a system of non-linear equations. A solution of such a system requires at least as many... [Pg.144]

The review article by Egan examines several predictive approaches, from fairly simple ones, using only one variable and showing a sigmoidal relationship [55], to increasingly more complex approaches where non-linear equations were successfully used to predict percent protein binding for neutral, basic and zwitterionic compounds across a set of 302 compounds, but where a similar attempt was used for acidic compounds the result was a poor fitting model [59]. [Pg.207]

In this paper we have reported a series of theoretical results which contribute to clarify how the many-body effects can be expressed in terms of the single particle density matrices 1-RDM and 1-TRDM. Whether it is possible to approximate a solution to this system of non-linear equations remains an open question after our initial study of this problem. [Pg.51]


See other pages where Non-linear equation is mentioned: [Pg.95]    [Pg.142]    [Pg.136]    [Pg.275]    [Pg.188]    [Pg.461]    [Pg.25]    [Pg.69]    [Pg.71]    [Pg.75]    [Pg.198]    [Pg.140]    [Pg.131]    [Pg.4]    [Pg.474]   
See also in sourсe #XX -- [ Pg.453 ]

See also in sourсe #XX -- [ Pg.453 ]

See also in sourсe #XX -- [ Pg.72 ]




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Equations linear

Kinetic equations are non-linear

Linearization, linearized equations

Linearized equation

Non-linear Poisson Boltzmann equation

Non-linear flux equations in electro-kinetic phenomena

Non-linear transport equations in gaseous medium

System of implicit non-linear equations the Newton-Raphson method

Systems of non-linear algebraic equations

Systems of non-linear equations

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