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Additional hypotheses

In fact, such n ( ) does not occur in the balances (8.2.2a). Injthe (fall) incidence matrix of, the n-th row equals zero as is isolated. Let be the remaining set of nodes. We shall assume [Pg.218]

This assumed, deleting the isolated nodes we have subgraph G [N, E,( ] of full incidence matrix [Pg.218]

Generally, Gui is not connected. Let 0, be the l-th connected component, of node set and arc set We thus have the partition [Pg.218]

Recall the observation after formula (8.2.16). In the inner double sum in (8.2.20), given s e Si the summation concerns only nodes n adjacent to node (splitter) s via some arc y e J,. It can happen that for some / 1, none of the nodes s e is adjacent to any n Nj.. This, however, means that even before deleting the splitters, no node e Nj was connected by a path with any node n t Nj, bec se ft is just the arcs j J, (i e ) that have been deleted. Then also the graph [Ni, Ei ] contains at least two connected components, one of them being a subgraph of node set Nj see Fig. 8-7 and imagine a subset of rows ( t 0) empty in the columns J n Ei, and with just two nonnull elements in any column of Jii (incidence matrix of Gi,). Then the sum over in (8.2.20) equals zero and we must have, in case of [Pg.219]

This means that the linear system (8.2.20) in variables ml is not generally solvable, unless the condition (8.2.21) is satisfied identically. If so, the condition (8.2.21) is added to the equations (8.2.2a). The case is conceivable but again, one feels that thCTe is something wrong in the model. We then cannot have G i as an isolated node in G [N, ] because [Pg.219]


Additional hypotheses for their mechanism of action have more recently been proposed. It is well known that proanthocyanidins are able to complex metals through their ortho-diphenol groups. This property is often viewed as imparting negative traits (e.g., reduction of the bioavailability of essential mineral micronutrients, especially iron and zinc) [87]. Since iron depletion causes severe limitation to microbial growth, their ability to bind iron has been suggested as one of the possible mechanisms explaining the antimicrobial activity of proanthocyanidins [88] (Table 1). [Pg.254]

Additional hypotheses concerning prostaglandin biosynthesis in P. homomalla resulted from isolation of 11R-HETE (76) from the polar lipid fraction [95]. Apparently, 11R-HETE (76) is also a minor product of incubations of arachidonic acid with acetone powder preparations of P. homomalla [95], In this alternate hypothesis (Scheme 8), an 11-hydroxy or 11-hydroperoxy-8,9-allene oxide intermediate is formed from a sequence of oxidations at C8 and Cll. Opening of the allene oxide to a transient C8 earboeation induces eycli-zation with a consequent addition of water to C15. This proposed pathway leads initially to formation of PGE2 (16 or 38), which following acetylation, elimination of acetic acid from Cl 1-12, and esterification, forms the observed major natural product in the coral, 15-acetoxy methyl PGA2 (36 or 54). Notably, if... [Pg.146]

This formula we will call the orbifold Euler number formula. In the case that the group G is abelian this conjecture has been proved in [Roan (1)] under certain additional hypotheses. In [Hirzebruch-Hofer (1)] some examples of this formula are studied. First they give a reformulation ... [Pg.54]

The methods based on wetting, Section III.8, all are undermined by the proved faultiness of the fundamental Eq. (1). Some of them employ additional hypotheses unlikely to be true. It is difficult to avoid the impression that, the more elaborate the experimental work, the more doubtful hypotheses are needed to evaluate the results of the measurements. [Pg.59]

Therefore we get our functor Ms C(l)s0 — M(l)s0 a pair ( >/s) as above exists. Suppose that So is the spectrum of a Noetherian complete local ring whose residue field has a finite p-basis. In this case the functor Ms induces an equivalence of the full subcategory of C(l)s0 consisting of group schemes which have multiplicative part equal to zero and a corresponding subcategory of At (1) s0 (Theorem 9.3). If the residue field is perfect then we can show under some additional hypotheses on (5,/s) that Ms C(l)s0 At(l)s0 is an equivalence (Theorem 10.2). [Pg.83]

The same procedure, somewhat simplified, was then employed to study the effects of perceptual concentration over a longer period of time. Although many of the phenomena that resulted seemed readily explainable on the basis of afterimages, autokinetic movement, phosphenes, and the like, certain data did not seem adequately accounted for by reference to familiar perceptual phenomena or by the use of such theoretical explanatory concepts as are currently available, e.g., suggestion or projection. Additional hypotheses seem necessary, and it is the purpose of this paper to present these data and the postulates derived from them. [Pg.297]

Note that, for the first result, the equation / (S) = /y(S) has at most one positive solution, and that the additional hypotheses imply uniqueness and global stability. Distinct Michaelis-Menten functions automatically satisfy all but the last hypothesis, which holds for almost all A. The second result shows that if the aforementioned equation can have two distinct solutions, yet / / , then an unstable positive rest point exists for some two-vessel gradostat. [Pg.151]

It will be assumed that / is continuously differentiable, D is positively invariant for (F.I), and (F.I) is dissipative in the sense that there is a compact subset of D into which every solution eventually enters and remains. The following additional hypotheses will be used. [Pg.294]

To study the range of possibilities the first molecular dynamics simulations of a DNA duplex tethered to a surface was performed [35,36] The technical aspects of simulations near surfaces are nontrivial, especially as concerns reliable boundary conditions [37], Molecular dynamics provides a more quantitative picture of the salt gradients and DNA structures near the surface responsible for changes in hybridization affinities and specificities than approximate (PB level mean field) theory and so may be used as a check on the simple analytical picture derived above. In addition simulation provides mechanistic clues which can form additional hypotheses for testing. [Pg.389]

The closure problem. Turbulent viscosity. Unlike the Navier-Stokes equations completed by the continuity equation, the Reynolds equation form an unclosed system of equations, since these contain the a priori unknown turbulent stress tensor cr with components (1.1.19). Additional hypotheses must be invoked to close system (1.1.18). These hypotheses are of much greater significance compared with those used for the derivation of the Navier-Stokes equations [430]. [Pg.9]

To sort out the relative importance of these, or additional hypotheses for explanation of enhanced EPTC degradation in soil, it is important that the microorganisms involved be identified and that the biochemical pathway(s) by which they degrade EPTC be determined. Although several different pathways have been proposed for carbamothioate degradation in soil, current information is based on studies conducted in animal and plant systems (10-12). [Pg.99]

In certain conditions discussed below, additional hypotheses permit a further reduction to only two variables the advantage of such a reduction is to facilitate the analysis of relay and oscillations in the phase plane. However, to be valid, these hypotheses require, for certain parameters, values that differ significantly from those that are experimentally available. Therefore the study of oscillations and relay will be carried out mainly in the three-variable system (5.12), or in the four-variable system (5.9a-d) from which it is derived. [Pg.202]

The basis for the scientific method is this from previous observations, a hypothesis is formed. An experiment is then planned to test this hypothesis. The test may either be one to substantiate the hypothesis or it may be a test to refute the hypothesis. The latter usually forms the more compelling evidence. Sometimes, for particularly strong proof, especially if the subject of the experiment is controversial, both experiments are conducted (see Heilman (2001) or de Kruif (1926) for examples). In the conduct of experiments, new observations are made that lead to additional hypotheses, so the pattern... [Pg.9]

Story quickly just to fit your data. Instead, focus on additional hypotheses and compounds to test them. [Pg.509]

We must remember that besides the flow of heat, there also exist other fluxes such as that of fluid, solutions of salt, the viscous stresses or even the flux of electrons or light. These laws are commonly based on the conservation of momentum and additional hypotheses, the justification of which lies in the satisfactory comparison of deductions from these laws with experimental observations. Such comparisons between theory and observation are limited. [Pg.156]

A release to the atmosphere, water or groundwater for option (2) above can be evaluated on the basis of additional hypotheses (see Ref. [47]) ... [Pg.71]

As consequences of supply chain collaboration, collaborative advantage and firm performance will be discussed in the following section. In addition, hypotheses will be developed in this chapter. [Pg.77]


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Additivity hypothesis

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