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Random connection methods

Methods in the random connection category include genetic algorithm approaches, CONCEPTS, CONCERTS, the dynamic ligand design [Pg.49]

During the run, a standard Metropolis-based Monte Carlo algorithm is used along with a simulated annealing protocol. Typically, several hundred thousand Monte Carlo steps are taken. This procedure takes only a few minutes on a fast workstation. Tests with dihydrofolate reductase, thymidylate synthetase (TS), and HlV-1 protease were carried out.i In each case, com- [Pg.52]


Random connection methods A special class of techniques combining some of the features of fragment connection and sequential buildup methods, along with bond disconnection strategies and ways to introduce randomness. [Pg.2]

All these different mechanisms of mass transport through a porous medium can be studied experimentally and theoretically through classical models (Darcy s law, Knudsen diffusion, molecular dynamics, Stefan-Maxwell equations, dusty-gas model etc.) which can be coupled or not with the interactions or even reactions between the solid structure and the fluid elements. Another method for the analysis of the species motion inside a porous structure can be based on the observation that the motion occurs as a result of two or more elementary evolutions that are randomly connected. This is the stochastic way for the analysis of species motion inside a porous body. Some examples that will be analysed here by the stochastic method are the result of the particularisations of the cases presented with the development of stochastic models in Sections 4.4 and 4.5. [Pg.286]

Kilvington and Leach have applied the random tweak algorithm to determine which of a series of possible acyclic linkers (determined randomly or systematically) is suitable to connect two isolated ligand fragments. The random tweak method is used to determine the amount of rotation each bond must undergo to match die ends of a flexible chain to the isolated fragments. ... [Pg.28]

A system is an ordered set of ideas, principles, and theories or a chain of operations that produces specific results to be a chain of operations, the operations need to work together in a regular relationship. A quality system is not a random collection of procedures (which many quality systems are) and therefore quality systems, like air conditioning systems, need to be designed. All the components need to fit together, the inputs and outputs need to be connected, sensors need to feed information to processes which cause changes in performance and all parts need to work together to achieve a common purpose i.e. to ensure that products conform to specified requirements. You may in fact already have a kind of quality system in place. You may have rules and methods which your staff follow in order to ensure product conforms to customer requirements, but they may not be documented. Even if some are documented, unless they reflect a chain of operations that produces consistent results, they cannot be considered to be a system. [Pg.160]

The flowsheet shown in the introduction and that used in connection with a simulation (Section 1.4) provide insights into the pervasiveness of errors at the source, random errors are experienced as an inherent feature of every measurement process. The standard deviation is commonly substituted for a more detailed description of the error distribution (see also Section 1.2), as this suffices in most cases. Systematic errors due to interference or faulty interpretation cannot be detected by statistical methods alone control experiments are necessary. One or more such primary results must usually be inserted into a more or less complex system of equations to obtain the final result (for examples, see Refs. 23, 91-94, 104, 105, 142. The question that imposes itself at this point is how reliable is the final result Two different mechanisms of action must be discussed ... [Pg.169]

The two conditions stated above do not assure the occurrence of gelation. The final and sufficient condition may be expressed in several ways not unrelated to one another. First, let structural elements be defined in an appropriate manner. These elements may consist of primary molecules or of chains as defined above or they may consist of the structural units themselves. The necessary and sufficient condition for infinite network formation may then be stated as follows The expected number of elements united to a given element selected at random must exceed two. Stated alternatively in a manner which recalls the method used in deriving the critical conditions expressed by Eqs. (7) and (11), the expected number of additional connections for an element known to be joined to a previously established sequence of elements must exceed unity. However the condition is stated, the issue is decided by the frequency of occurrence and functionality of branching units (i.e., units which are joined to more than two other units) in the system, on the one hand, as against terminal chain units (joined to only one unit), on the other. [Pg.361]

In this chapter, we provide a general overview of the field of chemometrics. Some historical remarks and relevant literature to this subject make the strong connection to statistics visible. First practical examples (Section 1.5) show typical problems related to chemometrics, and the methods applied will be discussed in detail in subsequent chapters. Basic information on univariate statistics (Section 1.6) might be helpful to understand the concept of randomness that is fundamental in statistics. This section is also useful for making first steps in R. [Pg.17]


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See also in sourсe #XX -- [ Pg.2 , Pg.17 , Pg.49 ]




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