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Deterministic technique

The chaotic behavior is an interesting nonlinear phenomenon which has been intensively studied during last two decades. The deterministic techniques have been used to understand the d3mamical structure in several nonlinear systems [5], [6], [42]. Particularly, the two-phase flow systems present nonlinear d mamical behavior which can be studied by means of chaos criteria behavior [2], [17], [25], [31], [45], [51]. Two-phase flows they provide a rich variety of cases whose dynamics lead to oscillatory patterns. The following published results are example ... [Pg.301]

The flow structure in a tall vertical bubble column was analyzed using deterministic techniques. The characterization of the two-phase flow structure was realized in the middle section where the flow is fully developed (measuring section). Three cases under different volume fraction of liquid were shown. The results can be resumed as follows ... [Pg.314]

Therefore molecular dynamics is a deterministic technique given an initial set of positions and velocities, the subsequent time evolution is in principle completely determined. The computer calculates a trajectory in a 6A-dimensional phase space (3A positions and 3A momenta). However, such trajectory is usually not particularly relevant by itself. Molecular dynamics is a statistical mechanics method. Like Monte Carlo, it is a way to obtain a set of configurations distributed according to some statistical distribution function, or statistical ensemble. [Pg.905]

Statistical Models. Due to the difficulties involved in calculating the composition distributions by purely deterministic techniques, statistical methods have been developed from which not only the CCD can be obtained but also the sequence length distribution. These methods view the chain growth as an stochastic process having possible states resulting from the kinetic mechanisms. Early work on this approach was reported by Merz, Alfrey and Goldfinger (4) who derived the copolymerization equation and the SLD for the ultimate effect case. Alfrey Bohrer and Mark (19) and Ham (9) formalized this approach. [Pg.90]

Broadly speaking there are two ways of calculating likelihood. The first is through the use of deterministic techniques such as fault tree and ETA as discussed above. A mathematical model of the system is created, data is entered into the model and system performance is calculated. Such an analysis is basically quite simple either an equipment item operates as required, or it does not. Yet real-world actual equipment performance is usually much more complex. [Pg.644]

Hazard analysis results are summarized and displayed. A final hazard classification of the SNL HCF and the radioactive material storage areas, consistent with DOE-STD-1027-92, is also presented (DOE 1992b). Finally, a limited set of bounding hazards is Identified for further development using quantitative, deterministic techniques In Section 3.4, "Accident Analysis."... [Pg.141]

According to Ret [1], the plant design is required to minimize sensitivity to PIEs, which are selected on the basis of probabilistic or deterministic techniques. Appropriate measures for prevention and mitigation should be... [Pg.17]

Other methods which are applied to conformational analysis and to generating multiple conformations and which can be regarded as random or stochastic techniques, since they explore the conformational space in a non-deterministic fashion, arc genetic algorithms (GA) [137, 1381 simulation methods, such as molecular dynamics (MD) and Monte Carlo (MC) simulations 1139], as well as simulated annealing [140], All of those approaches and their application to generate ensembles of conformations arc discussed in Chapter II, Section 7.2 in the Handbook. [Pg.109]

CAD /CAM techniques have provided the framework for using the computer as a tool in the drawing and analysis of chemical stmctures and, more recently, in the use of chemical stmctures to design reaction pathways and new products. The essential elements in these appHcations of CAD/CAM are that the possible stmctures are relatively deterministic and that allowable changes in stmcture through reaction are governed by thermodynamic, stoichiometric, and steric constraints. [Pg.63]

Particle trajectories can be calculated by utilizing the modern CFD (computational fluid dynamics) methods. In these calculations, the flow field is determined with numerical means, and particle motion is modeled by combining a deterministic component with a stochastic component caused by the air turbulence. This technique is probably an effective means for solving particle collection in complicated cleaning systems. Computers and computational techniques are being developed at a fast pace, and one can expect that practical computer programs for solving particle collection in electrostatic precipitators will become available in the future. [Pg.1228]

We go next to the analysis and failure analysis block in Figure 7-11. That is, we consider the initial configuration with a particular material or materials. Then, for the prescribed loads, we perform a set of structural analyses to get the various structural response parameters like stresses, displacements, buckling loads, natural frequencies, etc. Those analyses are all deterministic processes. That is, within the limits of accuracy of the available analysis techniques, we are able to predict a specific set of responses for a particular structural configuration. We must know how a particular structural configuration behaves so we can compare the actual behavior with the desired behavior, i.e., with the design requirements. [Pg.381]

By far the most common methods of studying aqueous interfaces by simulations are the Metropolis Monte Carlo (MC) technique and the classical molecular dynamics (MD) techniques. They will not be described here in detail, because several excellent textbooks and proceedings volumes (e.g., [2-8]) on the subject are available. In brief, the stochastic MC technique generates microscopic configurations of the system in the canonical (NYT) ensemble the deterministic MD method solves Newton s equations of motion and generates a time-correlated sequence of configurations in the microcanonical (NVE) ensemble. Structural and thermodynamic properties are accessible by both methods the MD method provides additional information about the microscopic dynamics of the system. [Pg.349]

Our concepts of petroleum reserves and resources and their measurements are changing to reflect the uncertainty associated with these terms. Petroleum reseiwes have been largely calculated deterministically (i.e. single point estimates with the assumption of certainty). In the past decade, reseiwe and resource calculations have incorporated uncertainty into their estimates using probabilistic methodologies. One of the questions now being addressed are such as how certain arc you that the rcsciwcs you estimate arc the actual reseiwes and what is the range of uncertainty associated with that estimate New techniques arc required to address the critical question of how much petroleum we have and under what conditions it can be developed. [Pg.1007]

This important technique is introduced at this elementary level to demonstrate characteristics of the confidence level concept that would otherwise remain unrecognized. Two models are necessary, one for the deterministic, the other for the stochastic aspects. [Pg.41]

In this chapter we discuss techniques both for signal enhancement and signal restoration. Techniques to model or to reconstruct the deterministic part of a digital signal in the presence of noise are discussed in Chapter 41. [Pg.510]

The category of algebraic equation models is quite general and it encompasses many types of engineering models. For example, any discrete dsmamic model described by a set of difference equations falls in this category for parameter estimation purposes. These models could be either deterministic or stochastic in nature or even combinations of the two. Although on-line techniques are available for the estimation of parameters in sampled data systems, off-line techniques... [Pg.10]

Risk Assessment Systems. Most of the techniques, design methods and applications in this book are deterministic. That is, some worst-case accident is assumed to happen, its effects are calculated to the best of our ability, and systems or structures are then designed to contain, suppress or mitigate the explosion accident effect. [Pg.46]

Before seeing a (future ) whole integrated system, mixing UV-visible-infrared and fluorimetric methods, the first route is the development of UV-based microsystems, including some relevant spectral exploitation techniques such as the semi-deterministic one [69,70]. [Pg.266]

So far, only techniques, starting from some initial point and searching locally for an optimum, have been discussed. However, most optimization problems of interest will have the complication of multiple local optima. Stochastic search procedures (cf Section 4.4.4.1) attempt to overcome this problem. Deterministic approaches have to rely on rigorous sampling techniques for the initial configuration and repeated application of the local search method to reliably provide solutions that are reasonably close to globally optimal solutions. [Pg.70]


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Deterministic

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