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Transform algebraic system

In CED, a number of different iterative solvers for linear algebraic systems have been applied. Two of the most successful and most widely used methods are conjugate gradient and multigrid methods. The basic idea of the conjugate gradient method is to transform the linear equation system Eq. (38) into a minimization problem... [Pg.166]

This algebraic system is diagrammed in Figure 1.2. The input to the system is the independent variable x. The output from the system is the dependent variable y. The transform that relates the output to the input is the well defined mathematical relationship given in Equation 1.1. The mathematical equation transforms a given value of the input, x, into an output value, y. If x = 0, then y = 2. If x = 5, then y = 7, and so on. In this simple system, the transform is known with certainty. [Pg.2]

Just as there are many different types of systems, there are many different types of transforms. In the algebraic system pictured in Figure 1.2, the system transform is the algebraic relationship y = a + 2. In the wine-making system shown in Figure 1.3, the transform is the microbial colony that converts raw materials into a Hnished wine. Transforms in the chemical process industry are usually sets of chemical reactions that transform raw materials into finished products. [Pg.14]

We will take the broad view that the system transform is that part of the system that actively converts system factors into system responses. A system transform is not a description of how the system behaves a description of how the system behaves (or is thought to behave) is called a model. Only in rare instances are the system transform and the description of the system s behavior the same - the algebraic system of Figure 1.2 is an example. In most systems, a complete description of the system transform is not possible - approximations of it (incomplete models) must suffice. Because much of the remainder of this book discusses models, their... [Pg.14]

Remark 1 8. The algebraic stack S(g,p) has a natural involution defined as follows the involution transforms the system... [Pg.74]

A few examples will be demonstrated in the following section. Each feature was incorporated in the software because it has been found necessary or useful in some modelling project. All the modelling tasks that previously required tailor made solutions in each project can now be solved in a unified manner in the ModEst environment. ModEst is able to deal with explicit algebraic, implicit algebraic (systems of nonlinear equations) and ordinary differential equations. As the standard way to handle PDE systems, the Numerical Method of Lines, which transforms a PDE system to a number of ODE components is used. In addition, any model with a solver provided may be dealt with as an algebraic system. The basic numerical tools are contained in the well tested public domain software (Bias, Linpack, Eispack, LSODE). [Pg.457]

The method, considered in this paper, permits to solve a uniqueness problem of an IP and it also transforms the initial model to a form convenient for tlae estimation of functional combinations. The algorittim has a simple realization in computer algebra systems (such as, e.g. REDUCE [83). [Pg.578]

Here, we have introduced some rather abstract concepts (vector spaces, linear transformations) to analyze the properties of linear algebraic systems. For a fuller theoretical treatment of these concepts, and their extension to include systems of differential equations, consult Naylor Sell (1982). [Pg.32]

The principal topics in linear algebra involve systems of linear equations, matrices, vec tor spaces, hnear transformations, eigenvalues and eigenvectors, and least-squares problems. The calculations are routinely done on a computer. [Pg.466]

Fig. 4.1 Block diagram of a closed-loop control system. R s) = Laplace transform of reference input r(t) C(s) = Laplace transform of controlled output c(t) B s) = Primary feedback signal, of value H(s)C(s) E s) = Actuating or error signal, of value R s) - B s), G s) = Product of all transfer functions along the forward path H s) = Product of all transfer functions along the feedback path G s)H s) = Open-loop transfer function = summing point symbol, used to denote algebraic summation = Signal take-off point Direction of information flow. Fig. 4.1 Block diagram of a closed-loop control system. R s) = Laplace transform of reference input r(t) C(s) = Laplace transform of controlled output c(t) B s) = Primary feedback signal, of value H(s)C(s) E s) = Actuating or error signal, of value R s) - B s), G s) = Product of all transfer functions along the forward path H s) = Product of all transfer functions along the feedback path G s)H s) = Open-loop transfer function = summing point symbol, used to denote algebraic summation = Signal take-off point Direction of information flow.
In the context of chemical kinetics, the eigenvalue technique and the method of Laplace transforms have similar capabilities, and a choice between them is largely dependent upon the amount of algebraic labor required to reach the final result. Carpenter discusses matrix operations that can reduce the manipulations required to proceed from the eigenvalues to the concentration-time functions. When dealing with complex reactions that include irreversible steps by the eigenvalue method, the system should be treated as an equilibrium system, and then the desired special case derived from the general result. For such problems the Laplace transform method is more efficient. [Pg.96]

For both of these cases, Eqs. (13)—(15) constitute a system of two linear ordinary differential equations of second order with constant coefficients. The boundary conditions are similar to those used by Miyauchi and Vermeulen, which are identical to those proposed by Danckwerts (Dl). The equations may be transformed to a dimensionless form and solved analytically. The solutions may be recorded in dimensionless diagrams similar to those constructed by Miyauchi and Vermeulen. The analytical solutions in the present case are, however, considerably more involved algebraically. [Pg.89]

A 5-point finite difference scheme along with method of lines was used to transform the partial differential Equations 4-6 into a system of first-order differential and algebraic equations. The final form of the governing equations is given below with the terms defined in the notation section. [Pg.139]

The basic principles are described in many textbooks [24, 26]. They are thus only sketchily presented here. In a conventional classical molecular dynamics calculation, a system of particles is placed within a cell of fixed volume, most frequently cubic in size. A set of velocities is also assigned, usually drawn from a Maxwell-Boltzmann distribution appropriate to the temperature of interest and selected in a way so as to make the net linear momentum zero. The subsequent trajectories of the particles are then calculated using the Newton equations of motion. Employing the finite difference method, this set of differential equations is transformed into a set of algebraic equations, which are solved by computer. The particles are assumed to interact through some prescribed force law. The dispersion, dipole-dipole, and polarization forces are typically included whenever possible, they are taken from the literature. [Pg.271]

Complex systems can often be represented by linear time-dependent differential equations. These can conveniently be converted to algebraic form using Laplace transformation and have found use in the analysis of dynamic systems (e.g., Coughanowr and Koppel, 1965, Stephanopolous, 1984 and Luyben, 1990). [Pg.80]

Concepts in quantum field approach have been usually implemented as a matter of fundamental ingredients a quantum formalism is strongly founded on the basis of algebraic representation (vector space) theory. This suggests that a T / 0 field theory needs a real-time operator structure. Such a theory was presented by Takahashi and Umezawa 30 years ago and they labelled it Thermofield Dynamics (TFD) (Y. Takahashi et.al., 1975). As a consequence of the real-time requirement, a doubling is defined in the original Hilbert space of the system, such that the temperature is introduced by a Bogoliubov transformation. [Pg.193]

The use of Laplace transfonnations yields some very useful simplifications in notation and computation. Laplace-transforming the linear ordinary differential equations describing our processes in terms of the independent variable t converts them into algebraic equations in the Laplace transform variable s. This provides a very convenient representation of system dynamics. [Pg.303]

The examples below illustrate the use of the bilinear transformation to analyze the stability of sampled-data systems. We can use all the classical methods that we are used to employing in the s plane. The price that we pay is the additional algebra to convert to ID from z. [Pg.674]

The big advantage of this method is that the analytical step of taking the z transformation is eliminated. You just deal with the original continuous transfer functions. For complex, high-order systems, this can eliminate a lot of messy algebra. [Pg.681]

The fluctuations are the consequence of nondistributivity of the A transformation. We need a new mathematical framework (i.e., nondistributive algebra) to analyze nonintegrable systems. This fact reminds us that whenever we found new aspects in physics, we needed new mathematical frameworks, such as calculus for Newton mechanics, noncommutative algebra for quanmm mechanics, and the Riemann geometry for relativity. [Pg.150]

Let G be a local transformation group that acts on M and is the symmetry group of system (5). Next, let the basis operators of the Lie algebra g of the group G be of the form... [Pg.275]


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