Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Partition/ problem

Note that if we relax the t binary variables by the inequalities 0 < y < 1, then (3-110) becomes a linear program with a (global) solution that is a lower bound to the MILP (3-110). There are specific MILP classes where the LP relaxation of (3-110) has the same solution as the MILP. Among these problems is the well-known assignment problem. Other MILPs that can be solved with efficient special-purpose methods are the knapsack problem, the set covering and set partitioning problems, and the traveling salesperson problem. See Nemhauser and Wolsey (1988) for a detailed treatment of these problems. [Pg.67]

Mulliken s formula for Nk implies the half-and-half (50/50) partitioning of all overlap populations among the centers k,l,... involved. On one hand, this distribution is perhaps arbitrary, which invites alternative modes of handling overlap populations. On the other hand, Mayer s analysis [172,173] vindicates Mulliken s procedure. So we may suggest a nuance in the interpretation [44] departures from the usual halving of overlap terms could be regarded as ad hoc corrections for an imbalance of the basis sets used for different atoms. But one way or another, the outcome is the same. It is clear that the partitioning problem should not be discussed without explicit reference to the bases that are used in the LCAO expansions. [Pg.94]

In the zero-coverage extreme, the BOC-MP analytic results are exact for atomic A adsorbates and are well defined for diatomic AB adsorbates. Formally, Eqs. (9)—(14) can be applied to polyatomic admolecules provided they are treated as quasidiatomics—in other words, if we define the effective parameters QA, QB, and DAB for the relevant molecular fragments A and B. Actually, we have already done such partitioning while extending Eqs. (11)—(14) to Eqs. (17)-(20). Now let us discuss the partitioning problem in a more systematic way. [Pg.113]

Very recently Sinha et. al /13 6/ have analytically shown that the CC—based LRT for IP is algebraically equivalent to the CC formalism of Haque and Mukherjee/69/ for one-hole valence problem. This indicates that the CC equations for determining the IP s can be cast into an equivalent eigenvalue equation. In fact Sinha et. aj /136/ have demonstrated that the relation between the CC-LRT for IP and the errresponding CC theory is the same as that between a Cl problem and the associated partitioned problem as obtained by the Soliverez transformation/137/. For open-shells containing more than one valence, the correspondence between the CC-LRT and the CC equations no longer holds, but Sinha et. al showed the CC... [Pg.349]

As in BLMs, failure to detect activity in LU Vs does not imply that the synthetic ion channel or pore does not exist. As a general rule, the difficulty of identifying activity in LUVs increases with increasing selectivity of either pore or assay (for the unrelated partitioning problem, see 4.1) [3, 7-11]. In other words and similar to the situation in BLMs, the most interesting synthetic ion channels or pores are the most difficult ones to detect. Tire HPTS assay is arguably the most useful assay to begin with because of its poor selectivity (Fig. 11.5c) [9-11]. [Pg.397]

As expected by analogy to the ordinary Hirshfeld partitioning problem of equation (93a), the solution of this modified missing information variational principle gives ... [Pg.174]

In order to avoid the overlap partitioning problem while extending this concept to more elaborated wave-functions, one may use the natural populations defined from Lowdin s orthogonalized atomic orbitals [25] which diagonalize the first-order density matrix ... [Pg.63]

The matrix equation (32) can be modified to give the S-matrix elements directly. To this end we retain the first rows of the partitioned problem and add the boundary conditions from Eqs. (8) and (11) as... [Pg.323]

The driver-scheduling problem is formulated mathematically as a set-partitioning problem, a spe-citil type of integer-programming (IP) problem (Nemhauser and Wolsey 1988 Bradley et al. 1977). [Pg.813]

The presented formulation is a set-partitioning problem with additional side constraints. For a freight transportation company with 10,000 tractors and 15,000 drivers in the continental United States, the problem formulated above is too large to be solved for the whole country. Often, however. [Pg.813]

Simple Q-mode factor analysis fails to provide a direct solution to the partitioning problem. This is because (1) the vectors generated by factor analysis are not composition vectors and therefore cannot be used to indicate the absolute composition of the end-members (2) the factor scores only give a relative measure of the importance of each variable in each end-member and also reflect any scaling done on the data set prior to the analysis (such as transforming variable values to percent of range or normahzing variables to equal means) ... [Pg.359]

The resulting winner determination problem was a set-partitioning problem. Cost was not the only criterion. Carrier-reliability, load balancing and incumbency concerns mattered to THD. These nonmonetary preferences were not revealed to the bidders. [Pg.286]

In the set covering problem every row has to be covered by at least one column. In the set partitioning problem, every row has to be covered by exactly one column. Otherwise the two problems are the same. Thus, the only change in the IP model is that constraints given by Equation 5.22 will now become equalities ... [Pg.240]

An additional problem with seawater is that any added CB spike may not be in the same form as was originally present in the sample. The role of colloids is uncertain, and partitioning problems may result in differences between liquid-liquid and solid adsorbent extractions of seawater. Until more information is available, we recommend the internal standard method with the whole range of CBs encountered in the samples to check the procedure for recoveries. Such tests should be repeated on a regular basis, for example, once per month. For routine analyses the external standard method suffices. With this issue we are facing a dilemma without an effective internal standard we cannot know the exact phase distribution of the analyte on the other hand, without knowledge of the phase distribution we cannot be certain if we add the correct internal standard. [Pg.498]

Another oil/water partitioning problem. Assume that a drug molecule partitions from water to oil with a partition coefficients Ki = 1000 at U = 300 K, and K, = 1400 at T, = 320 K. [Pg.299]

This type of partitioning is not addressed by APARTY because it is a problem of allocating the data path such that it can be divided vertically to produce the bit-slices, it is not a behavioral level partitioning problem. [Pg.84]

As has been shown in Section 3.4, COSMO-RS provides access to the thermodynamic parameters of solvents as well as of solute molecules. It provides the knowledge of the chemical potential of any compound in any fluid. Thus COSMO-RS enables the handling of almost any partition problem of compounds between liquid and gaseous phases. In this context it is important that COSMO-RS handles multicomponent mixtures without additional complications, because it does not make any mean-field approximation. Therefore multicomponent mixtures are described almost as reliably as binary mixtures or pure liquids. [Pg.614]


See other pages where Partition/ problem is mentioned: [Pg.51]    [Pg.427]    [Pg.418]    [Pg.172]    [Pg.152]    [Pg.575]    [Pg.14]    [Pg.1346]    [Pg.62]    [Pg.68]    [Pg.159]    [Pg.187]    [Pg.45]    [Pg.258]    [Pg.240]    [Pg.126]    [Pg.72]    [Pg.429]    [Pg.84]    [Pg.91]    [Pg.123]    [Pg.512]    [Pg.37]    [Pg.139]    [Pg.167]    [Pg.4]   
See also in sourсe #XX -- [ Pg.14 , Pg.69 , Pg.76 , Pg.106 , Pg.176 ]




SEARCH



© 2024 chempedia.info