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INDEX parameterization

In Section II, we presented the computational model involved in branching from a node, cr, to a node aa,. In this model, it was necessary to interpret the alphabet symbol a, and ascribe it to a set of properties. In the same way, we have to interpret o- as a state of the flowshop, and for convenience, we assigned a set of state variables to tr that facilitated the calculation of the lower-bound value and any existing dominance or equivalence conditions. Thus, we must be able to manipulate the variable values associated with state and alphabet symbols. To do this, we can use the distinguishing feature of first-order predicates, i.e., the ability to parameterize over their arguments. We can use two place predicates, or binary predicates, where the first place introduces a variable to hold the value of the property and the second holds the element of the language, or the string of which we require the value. Thus, if we want to extract the lower bound of a state o-, we can use the predicate Lower-bound Ig [cr]) to bind Ig to the value of the lower bound of cr. This idea extends easily to properties, which are indexed by more than just the state itself, for example, unit-completion-times, v, which are functions of both the state and a unit... [Pg.304]

Our goal is to estimate the function P(r) from the set of discrete observations Y(tj). We use a nonparametric approach, whereby we seek to estimate the function without supposing a particular functional form or parameterization. We require that our estimated function be relatively smooth, yet consistent with the measured data. These competing properties are satisfied by selecting the function that minimizes, for an appropriate value of the regularization parameter X, the performance index ... [Pg.366]

Finally, the catalyst mixing problem can be converted from an index three problem to an index zero problem by parameterizing the control profile using variable length piecewise constant functions. (This approach is acceptable because of the known form of the optimal control profile.) The solution using this approach also matches the analytical solution within numerical tolerances. [Pg.244]

The flexibility index can be defined by considering how much larger (or smaller) the expected uncertainty range 0 must be scaled so that it exactly fits inside feasible region R (Fig. 5). The family of scaled hyperrectangles 0( ) can be parameterized by scale factor s as... [Pg.19]

Refinements, parameterization, and the complete COSMO-RS 113 7.1.4 Local shape index... [Pg.113]

Various techniques, such as graphic illustrations (e.g., isobolograms), mixture toxicity indices (e.g., an additivity index), formulas, or fully parameterized models, exist for predicting an expected combined effect based on concentration addition or response addition (for review, see Bodeker et al. 1990). The quantitative relationship between the expected combined effect calculated according to concentration addition or response addition depends (in addition to other factors) primarily on the steepness of the concentration response relationship of the individual components (Drescher and Bodeker 1995). Concentration addition predicts a higher combined effect as compared to response addition when the mixture components have steep concentration response relationships, whereas the opposite is true for flat concentration response relationships of the mixture components. [Pg.140]

The first stage of the consideration of the effect of aerosol on climate is the modeling of aerosol properties. The models (based on statistically reliable field-measurements data) are to parameterize such characteristics as complex refractive index of particles m = n — ki), their shape and size distribution, vertical profile of aerosol concentrations, as well as variability of these parameters in time and due to humidity. [Pg.282]

Measured size distributions of salt particles are monomodal and can by parameterized by the power law, with the index varying within 0.97-4.2 (average 2.3-2.6). The density of MSA particles is close to 2.35 — 2.40 g/m The spatial distribution of Cn MSA (r > 1 pm) for different regions of the world ocean can be illustrated by the following values in the Pacific Ocean Cn = (1.2-1.5) cm in the Indian Ocean (0.9-1.0) cm" near the Australian coastline 0.4 cm near the boundaries of the Antarctic ice sheet (1.8-2.1) cm" and near the Black Sea coastline (0.32-1.93) cm" [8]. The vertical distribution of Cn MSA has some specific features. A maximum of Cn distribution is often observed at altitudes of several hundred meters (apparently, because of a decrease in the Cn MSA near the water surface, resulting from the capture of salt particles by sea waves). At altitudes 2-3 km the value of Cn MSA constitutes < 1 % of the total Cn value, which is explained by the cloud filter . However, over land, near the coastline, at an altitude of 3 km, Cn MSA is somewhat higher than at the same level over the sea surface. This is connected with a more intensive turbulence over land. In general, sea-salt aerosol particles have to be chemically composed of dried sea water 88.7% chlorides, 70.8% sulfates, 0.3% carbonates, and 0.2% other salts. [Pg.288]

To model the randomized motion of the Brownian particle, the concept of a random walk is typically used. A random walk is an example of a stochastic process, a collection of random variables parameterized by either a discrete or continuous index parameter [269, 314]. A random walk is a discrete stochastic process in which the state X at a given instant (defined by the index n) is related to the state X i, at step n — 1 by an offset that may be viewed as a random variable. That is, we have... [Pg.225]

Miner axiomatizes a parameterized type, Stream[a] with cons, head, and tail constructors subject to the usual identities. He defines an indexing accessor, nth (Stream[a], Nat) a and then postulates ... [Pg.265]

On the other hand, since a model is a simplification of reality, it has been argued that every model is definitely false (Morgan and Henrion, 1990) one may say that one model is better than another, in the sense that it produces more accurate predictions, bnt not that it is more probable therefore, it seems inappropriate to assign probabilities of model correctness. A proposed way out consists in including the models into a meta-model parameterized with one index parameter whose values (1,2,... ) are associated to... [Pg.1632]

Data about the imperviousness of a faultless liner system under defined boundary conditions for as large a number of pollutants and soil materials as possible form an important component of the characterisation of the efficacy of this liner for instance in comparison to equivalent alternative liner systems. Therefore, in the following, a parameterization will be discussed for the permeation rate (or the permeability) and the induction time for diffusive mass transport in the composite liner consisting of a geomembrane and a compacted clay liner (or more generally a porous mineral material). Quantities, which refer to the geomembranes, will be denoted with index 1, such as thickness d and diffusion coefficient D, and quantities referring to the mineral liner will have index 2 such as thickness d2 and effective diffusion coefficient D2. The porosity of the water-saturated mineral liner is denoted with 0 as above. [Pg.275]

The idea here is ultimately to combine all the characterization methods in order to parameterize the model of the component with an increasingly high confidence index , and increasingly rapidly. Figure 2.40 shows a diagrammatic representation of this original combinatorial approach. [Pg.115]

There are other metrics of information content, and several of them are based on the Shannon entropyAbout 10 years after introduction of the Shannon entropy concept, Jaynes formulated the maximum entropy approach, which is often referred to as Jaynes entropy and is closely related to Shannon s work. Jaynes introduction of the notion of maximum entropy has become an important approach to any study of statistical inference where all or part of a model system s probability distribution remains unknown. Jaynes entropy, or relations, which guide the parameterization to achieve a model of minimum bias, are built on the Kullback-Leibler (KL) function, sometimes referred to as the cross-entropy or relative entropy function, which is often used and shown (in which p and q represent two probability distributions indexed by k), as... [Pg.269]

The reflectivity spectmm R 0] measured upon the coupling to guided waves propagating in a polymer film carries information on its refractive index profile. This profile can be obtained by the analysis of R 6] and its changes can be tracked in real time. By using certain parameterization, the dependence of the refractive index of the polymer film on the distance perpendicular to the surface n x] can be obtained by fitting R 6] with a Fresnel reflectivity-based model (see Figure 4(a)). In order to... [Pg.650]


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See also in sourсe #XX -- [ Pg.199 , Pg.212 ]




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