Big Chemical Encyclopedia

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

Articles Figures Tables About

Dynamic component model

The above model assumes that both components are dynamically symmetric, that they have same viscosities and densities, and that the deformations of the phase matrix is much slower than the internal rheological time [164], However, for a large class of systems, such as polymer solutions, colloidal suspension, and so on, these assumptions are not valid. To describe the phase separation in dynamically asymmetric mixtures, the model should treat the motion of each component separately ( two-fluid models [98]). Let Vi (r, t) and v2(r, t) be the velocities of components 1 and 2, respectively. Then, the basic equations for a viscoelastic model are [164—166]... [Pg.184]

Lassiter, R.R., Modeling Dynamics of Biological and Chemical Components on Aquatic Ecosystems, U.S. Environmental Protection Agency Report No. EPA-660/3-75-012, Washington, D.C., 1975. [Pg.358]

For the data of streams and equipment models, ASPEN utilizes a plex data structure of the type proposed by Evans, et al. (3) Information is stored in blocks of contiguous locations known as beads. Beads of any length are created dynamically from a pool of free storage which may be thought of as a lengthy FORTRAN array. The combination of the preprocessor approach and the plex data structure has resulted in the absence of dimensional constraints on the system. There are no maximum numbers of streams, components, models, stages in a column, etc. except as limited by the total memory available. [Pg.291]

In addition to light interception, the acquisition of minerals (e.g., nitrogen, phosphorous, and sulfur) from the environment is vital for photosynthetic processes to proceed efficiently. Chemical composition is one component of dynamic simulation modeling (Denoroy, 1996). [Pg.331]

The slow component in the solvation TCF should have contributions both from the protein surface and from the hydration water. The DEM has been successful in quantifying the contribution of the hydration water to this slow dynamics. According to this model, dynamical equilibrium between the bound and free water introduces a slow timescale in the collective reorientational of the hydration water, which in turns slows down the solvation dynamics (Nandi and Bagchi, 1997 Pal et al., 2002 Bhattacharyya et al., 2003). [Pg.18]

Figure 8.10 Dynamic component model for machine learning... Figure 8.10 Dynamic component model for machine learning...
When the new approach for dynamic component modeling is applied to the software component for de-identification of protected personal information to comply with the privacy laws, the same component can be used for other... [Pg.380]

Figure 8.12 De-identification from the dynamic component model perspective... Figure 8.12 De-identification from the dynamic component model perspective...
Radach, G. (1980) Preliminary simulations of the phytoplankton and phosphate dynamics during FLEX 76 with a simple two-component model. Meteor Forschungen-Ergebnisse, A22, 151-163. [Pg.359]

Langewouters, G.J., Wesseling, K.H. and Goedhard, W.J.A. (1985) The pressure dependent dynamic elasticity of 35 thoracic and 16 abdominal human aortas in vitro described by a five component model. J. Biomech., 18, 613-620. [Pg.104]

With a sophisticated software package, the verification of the default pure component model parameters can be performed fast and easily. Often the results can be judged graphically. Hopefully, in most cases the user will find good agreement between the calculated and the experimental data stored in the factual data bank. Eut sometimes also poor results may be obtained. As an example, the dynamic viscosity of hexafluorobenzene is shown in Figure 11.3. Deviations larger than 200% between calculated and experimental data are obtained. The reason for the poor results is that the parameters were fitted to predicted data and not to the data available in the literature. The deviation is caused by the fact that the chosen predictive method leads to poor dynamic viscosities for fluorine compounds. ... [Pg.492]

SehneidCT T, Stoll E (1978) Molecular dynamics study of a three-dimensional n-component model for distortive phase transitions. Phys Rev B 17 1302-1322... [Pg.105]

There are a number of modeling approaches that can be used with process control systems. Whereas mathematical models based on the chemistry and physics of the system represent one alternative, the typical process control model utilizes an empirical input/output relationship, the so-called black-box model. These models are found by experimental tests of the process. Mathematical models of the control system may include not only the process but also the controller, the final control element, and other electronic components such as measurement devices and transducers. Once these component models have been determined, one can proceed to analyze the overall system dynamics, the effect of different controllers in the operating process configuration, and the stability of the system, as well as obtain other usefid information. [Pg.1968]

The mathematical model consists of a system of equations into which the above-mentioned quantities are entering. Here a distinction is made between static and dynamic models. Dynamic models observe the time-dependent system behavior static models will only monitor individual states of the system at constant input values. If the output vector Y consists of n components of the value and the vector W of m components IV, the static model, in a simple case, can be expressed by an implicit system of equations of the following type ... [Pg.36]

Each of these modes is assigned to a generalized degree of freedom (q-set). The accuracy of the dynamic reduction step is determined by the number of retained normal modes nq. As the number of generalized degrees of freedom Uq needed for an accurate description of the dynamic behaviour of the component is usually several orders smaller than the number of internal dofs, the size of the component model is drastically reduced. [Pg.99]

The same types of graphic analysis for any choice of the matrix V are used. Here an example of the graphic analysis based on an industrial on-line data is presented. The figures illustrate results of static linear PLS model, in which NIR data fix>m an oil refinery is used to model density of the product The vectors in the algorithm are displayed graphically to illustrate the structure and variation in data. The basic plots are 1. ta versus it, The vectors (t,) decompose the data matrix X. Therefore the plots of t, versus tb show us the sample (time) variation in data. Fig 1 reveals that the process (samples) is changing with the time. Arrows in Fig 1 visualise the drift on 1.-4. PLS components. The dynamic behaviour can be clearly seen even on the first two score vectors. Therefore, it cannot be expected that the same model will be valid at the... [Pg.500]


See other pages where Dynamic component model is mentioned: [Pg.246]    [Pg.185]    [Pg.189]    [Pg.45]    [Pg.487]    [Pg.185]    [Pg.155]    [Pg.736]    [Pg.521]    [Pg.97]    [Pg.94]    [Pg.678]    [Pg.594]    [Pg.379]    [Pg.379]    [Pg.379]    [Pg.343]    [Pg.267]    [Pg.1218]    [Pg.290]    [Pg.15]    [Pg.1612]    [Pg.92]    [Pg.373]    [Pg.223]    [Pg.872]    [Pg.876]    [Pg.90]    [Pg.530]    [Pg.391]   
See also in sourсe #XX -- [ Pg.379 , Pg.380 , Pg.381 ]




SEARCH



4-component model

© 2024 chempedia.info