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Constitutional constraints

Treatment of Polish Nationals in Danzig , PCIJ Series A/B, No. 44 (1932), p. 24. See also the Vienna Convention on the Law of Treaties, which in Article 27 provides that A party may not invoke the provisions of its internal law as justification for its failure to perform a treaty. It has been said that this principle is a self-evident one (Hersch Lauterpacht, The Development of International Law by the International Court, London Stevens Sons, 1958, p. 262). For a critical examination of the labelling of this principle as such, see Masahiko Asada, International Regime-Making Treaties and Constitutional Constraints on Their National Implementation , Journal of International Law... [Pg.97]

For example, V4 is the probability of seeing a 4 of any color. If the die were unbiased, you would have 114 = 1 / 6, but if the die were biased, might have a different value. Row and column sums constitute constraints, which are biases or knowledge that must be satisfied as you predict the individual table entries,... [Pg.91]

Line packing The NTS, together with the regional transmission systems, constitute a considerable length of pipework operating at pressures of up to 70 bar. Design and minimum pressures set maximum pressures by operational constraints. Between these two, the pressure can be permitted to fluctuate. [Pg.287]

Although one of the two building blocks has to be symmetric to avoid constitutional isomers, the symmetry constraints differ from those of the 2 + 2 approach and this allows the synthesis of structures that would be difficult to obtain by other synthetic strategies. Consequently, the 3 + 1 strategy has been accepted and is an increasingly used method for porphyrin synthesis.49... [Pg.589]

Notice that those distribution functions that satisfy Eq. (4-179) still constitute a convex set, so that optimization of the E,R curve is still straightforward by numerical methods. It is to be observed that the choice of an F(x) satisfying a constraint such as Eq. (4-179) defines an ensemble of codes the individual codes in the ensemble will not necessarily satisfy the constraint. This is unimportant practically since each digit of each code word is chosen independently over the ensemble thus it is most unlikely that the average power of a code will differ drastically from the average power of the ensemble. It is possible to combine the central limit theorem and the techniques used in the last two paragraphs of Section 4.7 to show that a code exists for which each code word satisfies... [Pg.242]

Although energy conservation constraints dictate which VP channels are open, it is the nature of the intermolecular interactions, the density of states and the coupling strengths between the states that ultimately dictate the nature of the dynamics and the onset of IVR. These factors are dependent on the particular combinations of rare gas atom and dihalogen molecule species constituting the complex. For example, Cline et al. showed that, in contrast to He Bra, Av = 2 VP in the He Cla and Ne Cla complexes proceeds via a direct... [Pg.410]

The Rietveld Fit of the Global Diffraction Pattern. The philosophy of the Rietveld method is to obtain the information relative to the crystalline phases by fitting the whole diffraction powder pattern with constraints imposed by crystallographic symmetry and cell composition. Differently from the non-structural least squared fitting methods, the Rietveld analysis uses the structural information and constraints to evaluate the diffraction pattern of the different phases constituting the diffraction experimental data. [Pg.135]

The first step of the structure refinement is the appHcation of distance geometry (DG) calculations which do not use an energy function but only experimentally derived distances and restraints which follow directly from the constitution, the so-caUed holonomic constraints. Those constraints are, for example, distances between geminal protons, which normally are in the range between 1.7 and 1.8 A, or the distance between vicinal protons, which can not exceed 3.1 A when protons are in anti-periplanar orientation. [Pg.236]

In the construction of the matrix F of Eq. (63), the symmetrical equivalence of the two O-H bonds was taken into account. Nevertheless, it contains four independent force constants. As the water molecule has but three fundamental vibrational frequencies, at least one interaction constant must be neglected or some other constraint introduced. If all of the off-diagonal elements of F are neglected, the two principal constants, f, and / constitute the valence force field for this molecule. However, to reproduce the three observed vibrational frequencies this force field must be modified to include the interaction constant... [Pg.121]

Equations (113) and (109)—(112) constitute the objective function and constraints of a linear programming problem. Notice that in this formulation the minimization is carried out with respect to both H(0) and Linearization is effected at the expense of increasing the number of independent (decision) variables to 1 +, vf. However, it can be shown that each... [Pg.181]

Constraints (4.1), (4.2), (4.3), (4.4), (4.5) and (4.6) constitute a nonconvex nonlinear model due to constraints (4.3) and (4.4), which involve bilinear terms. Nonconvexity, and not necessarily nonlinearity, is a disadvantageous feature in any model, since global optimality cannot be guaranteed. Therefore, if can be avoided, it should. This is achieved by either linearizing the model or using convexification techniques where applicable. In this instance, the first option was proven possible as shown below. [Pg.76]

Constraints (4.10) still entails nonconvex bilinear terms comprising of a binary and a continuous variable. However, this type of bilinearity can be readily linearized exactly using Glover transformation (1975). Constraints (4.11), (4.12), (4.13), (4.14) and (4.15) together constitute a linearized form of constraints (4.10). In constraints (4.11), the first and the second bilinear terms from constraints (4.10) have been replaced by continuous variables Ti and T2, respectively. Ti is defined in constraints (4.12) and (4.13), and V2 in constraints (4.14) and (4.15). [Pg.76]

Scenario 4 Formulation for fixed water quantity with reusable water storage Constraints (4.18), (4.19), (4.3), (4.20), (4.16), (4.17), (4.21), (4.22), (4.23), (4.24), (4.25) and (4.26) together constitute a complete water reuse/recycle model for a situation in which the quantity of water in each water using operation is fixed. This is also a nonconvex MINLP for which exact linearization is not possible. [Pg.80]

The sequencing set of constraints focuses on capturing the time dimension, which is intrinsic in batch operations. The following constraints, which apply irrespective of the chosen scenario (scenario 1 or scenario 2), constitute the scheduling set of constraints for the proposed mathematical model. [Pg.107]

The two sets of constraints presented in Sections 3.1 and 3.2 constitute an overall mathematical model, which is used in the proposed two-stage solution algorithm. [Pg.110]

The duration constraints constitutes one of the most crucial constraints as it addresses the intrinsic aspect of time in batch plants. It simply states that the time at which a particular state is produced is dependent on the duration of task that produces the same state as follows. [Pg.129]

Constraints (10.1), (10.2), (10.8)-(10.14), in conjunction with the overall plant scheduling constraints, constitute a complete MILP formulation for direct heat integration in batch processes in a situation where the batch size is allowed to vary at different instances along the time horizon of interest. [Pg.225]

The foregoing constraints constitute the full heat storage model. With the exception of constraints (11.3)—(11.5), all the constraints are linear. Constraints (11.3)—(11.5) entail nonconvex bilinear terms which render the overall model a nonconvex MINLP. However, the type of bilinearity exhibited by these constraints can be readily removed without compromising the accuracy of the model using the so called Glover transformation, which has been used extensively in the foregoing chapters of this book. This is demonstrated underneath using constraints (11.3). [Pg.241]

Constraints (11.18), (11.19), (11.20) and (11.21) constitute the linearized version of constraints (11.3). The advantage of this linearization technique is that it is exact, which implies that global optimality is assured. The disadvantage, however, is that it requires the introduction of new variables and additional constraints. Consequently, the size of the model is increased. A similar type of linearization is also necessary for constraints (11.4) in order to have an overall MILP model which can be solved exactly to yield a globally optimal solution. [Pg.242]


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