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Vectors mathematical definition

Mathematical definition yields the clockwise handness toward a positive z-direction as positive and vice versa, like angular momentum. As time proceeds, the two vectors at z0 contrarotate and combine to give a linear polarization halfway between them,... [Pg.5]

Many theories developed in this book are expressed by equations or results involving continuous functions for example, the spatially variable concentration c(r). Materials systems are fundamentally discrete and do not have an inherent continuous structure from which continuous functions can be constructed. Whereas the composition at a particular point can be understood both intuitively and as an abstract quantity, a rigorous mathematical definition of a suitable composition function is not straightforward. Moreover, using a continuous position vector f in conjunction with a crystalline system having discrete atomic positions may lead to confusion. [Pg.7]

In (1.25), the terms inside the brackets can be reformulated by use of vector and tensor notations. By comparing the terms inside the brackets with the mathematical definitions of the nabla or del operator, the vector product between this nabla operator and the mass flux vector we recognize that these... [Pg.20]

Optimal control problems in optimization involve vector decision variables like the technological and socio-economic profiles to be determined for sustainabdity. It involves integral objective function and the underlying model is a differential algebraic system. Shastri and Diwekar [24] presented a mathematical definition of the sustainability hypothesis proposed by Cabezas and Path [16] based on FI. They assumed a system with n species, and calculated the time average Fb using Eq. [8.16]. [Pg.195]

Mathematically it would make no sense to define an absolute concept of correctness. We define only a relative concept. The definition of partial correctness is designed to capture the idea that a program viien fed with a proper input or inputs -an input vector satisfying some input criterion - will give, if and when it halts, an output or outputs fulfilling some designated criterion. [Pg.44]

The extension of vector methods to more dimensions suggests the definition of related hypercomplex numbers. When the multiplication of two three-dimensional vectors is performed without defining the mathematical properties of the unit vectors i, j, k, the formal result is... [Pg.12]

The definition of a mathematical space begins with the set of objects X, Y, Z,. .. that occupy the space (an intrinsically empty space being a physically problematic concept). Among the simplest algebraic structures that can characterize such objects is that of a linear manifold, also called a linear vector space, affine space, etc. By definition, such a manifold has only two operations— addition (X + Y) and multiplication by a scalar (AX)— resulting in each case in another element of the manifold. These operations have the usual distributive,... [Pg.424]

We will not try to give a definite description or classification of mathematical objects here. This section should be regarded merely as a collection of useful facts and nomenclature. We will cover the most common terms regarding continuous spaces in general and vector spaces, operators and matrices. We will not touch upon spinors, nor on tensors. [Pg.1]

Various approaches have been used to define detection limit for the multivariate situation [24], The first definition was developed by Lorber [19]. This multivariate definition is of limited use because it requires concentration knowledge of all analytes and interferences present in calibration samples or spectra of all pure components in the calibration samples. However, the work does introduce the important concept of net analyte signal (NAS) vector for multivariate systems. The NAS representation has been extended to the more usual multivariate situations described in this chapter [25-27], where the NAS is related to the regression vector b in Equation 5.11. Mathematically, b = NAS/ NAS and NAS = 1/ b. Thus, the norm of the NAS vector is the same as the effective sensitivity discussed in Section 5.4.9.1 A simple form of the concentration multivariate limit of detection (LOD) can be expressed as LOD = 3 MINI, where e denotes the vector of instrumental noise values for the m wavelengths. The many proposed practical approaches to multivariate detection limits are succinctly described in the literature [24],... [Pg.134]

There are two competing and equivalent nomenclature systems encountered in the chemical literature. The description of data in terms of ways is derived from the statistical literature. Here a way is constituted by each independent, nontrivial factor that is manipulated with the data collection system. To continue with the example of excitation-emission matrix fluorescence spectra, the three-way data is constructed by manipulating the excitation-way, emission-way, and the sample-way for multiple samples. Implicit in this definition is a fully blocked experimental design where the collected data forms a cube with no missing values. Equivalently, hyphenated data is often referred to in terms of orders as derived from the mathematical literature. In tensor notation, a scalar is a zeroth-order tensor, a vector is first order, a matrix is second order, a cube is third order, etc. Hence, the collection of excitation-emission data discussed previously would form a third-order tensor. However, it should be mentioned that the way-based and order-based nomenclature are not directly interchangeable. By convention, order notation is based on the structure of the data collected from each sample. Analysis of collected excitation-emission fluorescence, forming a second-order tensor of data per sample, is referred to as second-order analysis, as compared with the three-way analysis just described. In this chapter, the way-based notation will be arbitrarily adopted to be consistent with previous work. [Pg.478]

The third term in mass transport is dispersion. The dispersion describes the mass flow, which results from velocity variations due to the geometry and the structure of the rock system. From this definition it follows that the smaller the vector of convection the smaller the effect of dispersion. The other way round, an increasing effect of dispersion occurs with higher flow velocity. Consequently the mathematical description of the species distribution is an overlap of convection, diffusion, and dispersion. [Pg.58]

We used here a too large displacement of 2 and a for the construction of the matrices (relation (3.242)). However, the real computation uses a small displacement of the parameters. This explains the differences between both values of the vectors of errors as well as the evolution of the vector of the parameters along both iterations. The software of the mathematical model of the process is given by FRC(2, a). In this specific computation, we introduced definite values of 2 and a for the calculation of the corresponding temperatures (tg g jg, tg g jg, tgj, t etc) for points Cj and Sj respectively. [Pg.166]

Some remarks and definitions concerning states in quantum mechanics are called for here. Usually, a pure state in quantum mechanics is introduced with the help of a wave function 4. In modern terms, such a wave function if is called a state vector, because it can be viewed as an element in a mathematical vector space. In the case of a two-level system, I is given as a vector in a two-dimensional complex vector space... [Pg.104]

It is possible to justify several alternative definitions of the multicomponent diffusivities. Even the multicomponent mass flux vectors themselves are expressed in either of two mathematical forms or frameworks referred to as the generalized Fick- and Maxwell-Stefan equations. [Pg.267]

To express the force equilibrium condition in a mathematical form, we can now consider a force balance on an arbitrary surface element of a fluid interface, which we denote as A. A sketch of this surface element is shown in Fig. 2-14, as seen when viewed along an axis that is normal to the interface at some arbitrary point within A. We do not imply that the interface is flat (though it could be) - indeed, we shall see that curvature of an interface almost always plays a critical role in the dynamics of two-fluid systems. We denote the unit normal to the interface at any point in A as n (to be definite, we may suppose that n is positive when pointing upward from the page in Fig. 2-14) and let t be the unit vector that is normal to the boundary curve C and tangent to the interface at each point (see... [Pg.77]

Enforcing stoichiometric, capacity, and thermodynamic constraints simultaneously leads to the definition of a solution space that contains all feasible steady-state flux vectors. Within this set, one can find a particular steady-state metabolic flux vector that optimizes the network behavior toward achieving one or more goals (e g., maximize or minimize the production of certain metabolites). Mathematically speaking, an objective function has to be defined that needs to be minimized or maximized subject to the imposed constraints. Such optimization problems are typically solved via linear programming techniques. [Pg.208]

The mathematics concerning the definition and the use of the algebra Cl(M) are not very complicated. Anyone who knows what a vector space is will be able to understand the geometrical implications of this algebra. The lecture will be perhaps more difficult for the readers already acquainted with the complex formalism of the matrices and spinors, to the extent that the new language will appear different from the one that they have used. But the correspondence between the two formalisms is ensured in the text at each stage of the theory. [Pg.6]

In (6.18), a denotes the electric losses of the medium under study, H = HU H, Hw 7 is the magnetic intensity, and J = JU / J ]1 is a prearranged electric current density source used for the external excitation of the structure. Observe that (6.18c) constitutes the auxiliary differential equation form that provides the mathematical background of the frequency relationship between vectors D and E. Specifically, it is derived via the inverse Fourier transform of the Vn definition considering an eiwt variation. [Pg.151]


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Mathematical vector

Vectors definitions

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