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Constraints combination

Candid [26] combines features from Noah and Aria, such as the use of three-dimensional structure-based filters and ambiguous distance constraints, with the new concepts of network-anchoring and constraint combination that further enable an efficient and reliable search for the correct fold in the initial cycle of de novo NMR structure determinations. A flowchart of the Candid algorithm is given in Fig. 2.3. [Pg.56]

Candid provides two modes of constraint combination (further combination modes can be envisaged readily) 2-> 1 combination of all assignments of two long-range peaks each into a single constraint, and 4 -> 4 pair wise combination of the assignments of... [Pg.60]

Fig. 2.5 Schematic illustration of the effect of constraint combination in the case of two distance constraints, a correct one connecting atoms A and B, and a wrong one between atoms C and D. A structure calculation that uses these two constraints as individual constraints that have to... Fig. 2.5 Schematic illustration of the effect of constraint combination in the case of two distance constraints, a correct one connecting atoms A and B, and a wrong one between atoms C and D. A structure calculation that uses these two constraints as individual constraints that have to...
Structured catalysts are used in GT and microcombustor applications because of the severe pressure drop constraints combined with the requirement for a fast rate of... [Pg.375]

Environmental/Health/Safety Constraints Combination effects include both synergism and antagonism. These constraints combine the following activities ... [Pg.278]

The plant/controller simulation should be exercised many times, with many different combinations of active constraints. Eor each constraint combination, it is important to make sure that when constraint violations are unavoidable (more active constraints than MVs), the CV violations occur in the correct order, with the highest priority given to variables related to safety. [Pg.1259]

As expected, most algorithms have a way to deal with this situation. Typically, each CV can be given a weight, with lower-weigh ted CVs being violated first. The most important consideration in tuning for constraints is to ensure that a representative number of different constraint combinations are tested in an off-line environment, before the controller is run in the plant. [Pg.1259]

It must identify and remove all linear constraint combinations. [Pg.405]

F-MAS condition to analyse polymorphs of YAFG peptides [21] (Fig. 2.9). Obtained NMR structural constraints combined with theoretical gauge-including projector augmented wave (GIFAW) calculation data were used to deduce a molecular arrangement of peptides in the crystal lattice after thermal rearrangement. [Pg.80]

On a land site where space and weight are not normally constraints, advantage can be taken of tank type separation equipment such as wash tanks and settling tanks, and batch processing methods. Such equipment is generally cheaper to maintain than continuous throughput vessels, though a combination of both may be required. [Pg.262]

An implicit edge process is involved in the regularization process where A acts as a scale parameter which gives a constraint on the size of the homogeneous patches and p. comes from ho = -y/ p/A where ho is the threshold above which a discontinuity is introduced. We propose, then to combine these two functionals to obtain a satisfactory solution ... [Pg.331]

Since indistinguishability is a necessary property of exact wavefiinctions, it is reasonable to impose the same constraint on the approximate wavefiinctions ( ) fonned from products of single-particle solutions. Flowever, if two or more of the Xj the product are different, it is necessary to fonn linear combinations if the condition P. i = vj/ is to be met. An additional consequence of indistinguishability is that the h. operators corresponding to identical particles must also be identical and therefore have precisely the same eigenfiinctions. It should be noted that there is nothing mysterious about this perfectly reasonable restriction placed on the mathematical fonn of wavefiinctions. [Pg.26]

By combining the Lagrange multiplier method with the highly efficient delocalized internal coordinates, a very powerfiil algoritlun for constrained optimization has been developed [ ]. Given that delocalized internal coordinates are potentially linear combinations of all possible primitive stretches, bends and torsions in the system, cf Z-matrix coordinates which are individual primitives, it would seem very difficult to impose any constraints at all however, as... [Pg.2348]

But the methods have not really changed. The Verlet algorithm to solve Newton s equations, introduced by Verlet in 1967 [7], and it s variants are still the most popular algorithms today, possibly because they are time-reversible and symplectic, but surely because they are simple. The force field description was then, and still is, a combination of Lennard-Jones and Coulombic terms, with (mostly) harmonic bonds and periodic dihedrals. Modern extensions have added many more parameters but only modestly more reliability. The now almost universal use of constraints for bonds (and sometimes bond angles) was already introduced in 1977 [8]. That polarisability would be necessary was realized then [9], but it is still not routinely implemented today. Long-range interactions are still troublesome, but the methods that now become popular date back to Ewald in 1921 [10] and Hockney and Eastwood in 1981 [11]. [Pg.4]

In order to obtain this savings in the computational cost, orbitals are symmetry-adapted. As various positive and negative combinations of orbitals are used, there are a number of ways to break down the total wave function. These various orbital functions will obey different sets of symmetry constraints, such as having positive or negative values across a mirror plane of the molecule. These various symmetry sets are called irreducible representations. [Pg.125]

The principal organs involved in the peripheral clearance of hGH from the plasma are the kidney and fiver. hGH is cleared via glomerular filtration at the kidney and by a receptor-mediated mechanism at the fiver (58,59). In animal models, derivatives of hGH such as the 20,000 mol wt variant, oligomeric forms, and hGH complexed with GH-binding protein have been shown to be cleared from the semm at significandy lower rates than 22,000 mol wt hGH (60—62). The prolonged plasma half-life of these derivatives probably reflects a combination of decreased receptor affinity and size constraints on glomerular filtration. [Pg.198]

As different regulations have been adopted, the approach to controlling pollution has evolved. Initial regulations controlled solvent composition later regulations were concerned primarily with overall VOC reduction. More recent regulations have combined VOC reduction with composition constraints. [Pg.262]

Reformulating to reduce HAP solvents frequently means that solvent blend costs increase. The newer blends are generally not be as effective. For example, many coatings were usually formulated using ketones as the active solvents with aromatic hydrocarbons as diluents. This combination produced the most cost-effective formulations. However, when MEK, MIBK, toluene, and xylene became HAP compounds, less-effective solvents had to be used for reformulation. Esters are the most common ketone replacements, and aUphatic diluents would replace the aromatic hydrocarbons. In this situation, more strong solvent is required compared to the ketone/aromatic formulation and costs increase. The combination of reduced VOC emissions and composition constraints in the form of HAP restrictions have compHcated the formulator s task. [Pg.279]


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