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Combination of scales

In this subsection we shall construct two independent realizations of (55) on two independent levels and then we combine them. [Pg.111]

We begin with the first problem (Problem 1). Let itp be the number of particles whose trajectories are actually followed in computers. Since rip 106 1023, we shall choose to describe states of the particles by [Pg.111]

We proceed now to the problems (Problem 2) and (Problem 3). At least two levels of description are involved in direct molecular simulations. The first one is the level of the np-particle kinetic theory and the second is the level of fluid mechanics on which the external forces and the final results that we seek are formulated. We shall use the multiscale formulation developed above and combine the two levels. The two levels that we consider in this section are [Pg.112]

C2-np-particle kinetic theory with the state variables [Pg.112]

From the above two levels we construct now a third level as their combination  [Pg.113]


Mechanical properties of PNCs can also be estimated by using computer modeling and simulation methods at a wide range of length and time scales. Seamless movement from one scale to another, for example, from the molecular scale (e.g., MD) and microscale (e.g., Halphin-Tsai) to macroscale (e.g., finite element method, FEM), and the combination of scales (or the so-called multiscale methods) is the most important prerequisite for the efficient transfer and extrapolation of calculated parameters, properties, and numerical information across length scales. [Pg.76]

The characters are first normalized by rotating the original scanned image to correct for scanning error and by combinations of scaling under sampling and contrast and density adjustments of the scanned characters. In operation, the normalized characters are then presented to a multilayer perceptron neural network for recognition the network was trained on exemplars of characters form numerous serif and sans serif fonts to achieve font invariance. Where the output from the neural network indicates more than one option, for example 5 and s, the correct interpretation is determined from context. [Pg.56]

Figure 5 Vapor pressure and vapor-liquid phase boundary for methanol as a function of temperature from experiment (lines) and from simulation with combinations of scaling and polarization... Figure 5 Vapor pressure and vapor-liquid phase boundary for methanol as a function of temperature from experiment (lines) and from simulation with combinations of scaling and polarization...
Equations (16.56) and (16.57) provide a solution to the closure problem inasmuch as the turbulent fluxes have been related directly to the mean velocity and potential temperature. However, we have essentially exchanged our lack of knowledge of u u2 and u 2B for Km and Kt, respectively. In general, both Km and Kj are functions of location in the flow field and are different for transport in different coordinate directions. The variation of these coefficients, as we will see later, is determined by a combination of scaling arguments and experimental data. [Pg.741]

Thus we have arrived at the wavelet series representation of f(t) (also called the wavelet decomposition of f(t)). Alternatively, one could write f(t) as a linear combination of scaling and wavelet basis functions as follows... [Pg.72]

The OSC approach was also tested out here to complement the simple multiscale approach results. Since the number of scales tested for are 9 ( 1,2,..., 9 ), there are 511 different combinations of scales. 474 of these combinations resulted in perfect prediction in the calibration. What scales seem to dominate In order to answer this question, the relative distribution for the different scale combinations was performed. Scale combinations were grouped according to their error produced by DPLS and the distribution of which of the nine scales selected was recorded. Fig. 27 displays the results. [Pg.401]

The theory proposed by Halperin and Alexander (H-A theory) [60] is based on the structural scaling description of polymeric micelles outlined in Sect. 2.1.2. Using a combination of scaling theory and Kramers rate theory for diffusirai in an external potential [61], the expulsion rate for both crew-cut and star-like spherical micelles was derived. Moreover, Halperin and Alexander discussed different scenarios of chain exchange between micelles. [Pg.72]

Returning to the accurate formulae we see that certadn combinations of scaling functions simplify as a consequence of s = s and the fact that s x) is the same in protons and neutrons. [Pg.372]

Similar to the hardware-design problem for WSCs, the complexity of software development for a WSC hardware platform can be an obstacle for both workload and infrastmctnre software developers. The complexity derives from a combination of scale and limits of electronic technology and physics. For example, a processor accessing its local memory can do so at rates of more than 10 gigabytes per second, bnt accessing memory attached to another processor in the facility may only be feasible at rates that are slower by orders of magnitude. [Pg.19]

The basic driving force of localized corrosion or corrosion protection in numerous cases is the galvanic coupling of which the dimensional aspect is fixed by a combination of scales regarding interfacial processes or properties. At the electrolyte-metal interface, it is necessary to cortsider the microstmcture (incltrding all real-time modification induced for example by apphed stresses), the possible chemical changes at the sttrface of the material, and the electrolyte conductivity contribution, among others factors. [Pg.243]

There are times when the engineer in the field is called upon to identity scale samples. An operator may need to take immediate steps to remove scale from production tubing, flow lines, or other pieces of equipment, and time does not permit submitting a sample of the scale to a laboratory for analysis. The engineer must be able to determine whether the scale is calcium carbonate, iron carbonate, calcium sulfate, barium sulfate, or a combination of scales. The following procedures outline various methods that the field engineer may use to determine the type of scale in question. [Pg.191]

Of the three, cloud analysis is the least restrictive. Its name is derived from the characteristic cloud of results that appears in the IM versus EDP plane, where each point corresponds to one analysis (see Fig. 1). One can employ any combination of scaling and record set selection. At one end, one can employ only scaling, using a hxed... [Pg.89]

It suffices to carry out one such experiment, such as the expansion or compression of a gas, to establish that there are states inaccessible by adiabatic reversible paths, indeed even by any adiabatic irreversible path. For example, if one takes one mole of N2 gas in a volume of 24 litres at a pressure of 1.00 atm (i.e. at 25 °C), there is no combination of adiabatic reversible paths that can bring the system to a final state with the same volume and a different temperature. A higher temperature (on the ideal-gas scale Oj ) can be reached by an adiabatic irreversible path, e.g. by doing electrical work on the system, but a state with the same volume and a lower temperature Oj is inaccessible by any adiabatic path. [Pg.335]

As an example for an efficient yet quite accurate approximation, in the first part of our contribution we describe a combination of a structure adapted multipole method with a multiple time step scheme (FAMUSAMM — fast multistep structure adapted multipole method) and evaluate its performance. In the second part we present, as a recent application of this method, an MD study of a ligand-receptor unbinding process enforced by single molecule atomic force microscopy. Through comparison of computed unbinding forces with experimental data we evaluate the quality of the simulations. The third part sketches, as a perspective, one way to drastically extend accessible time scales if one restricts oneself to the study of conformational transitions, which arc ubiquitous in proteins and are the elementary steps of many functional conformational motions. [Pg.79]

Discriminant emalysis is a supervised learning technique which uses classified dependent data. Here, the dependent data (y values) are not on a continuous scale but are divided into distinct classes. There are often just two classes (e.g. active/inactive soluble/not soluble yes/no), but more than two is also possible (e.g. high/medium/low 1/2/3/4). The simplest situation involves two variables and two classes, and the aim is to find a straight line that best separates the data into its classes (Figure 12.37). With more than two variables, the line becomes a hyperplane in the multidimensional variable space. Discriminant analysis is characterised by a discriminant function, which in the particular case of hnear discriminant analysis (the most popular variant) is written as a linear combination of the independent variables ... [Pg.719]

Industrial scale polymer forming operations are usually based on the combination of various types of individual processes. Therefore in the computer-aided design of these operations a section-by-section approach can be adopted, in which each section of a larger process is modelled separately. An important requirement in this approach is the imposition of realistic boundary conditions at the limits of the sub-sections of a complicated process. The division of a complex operation into simpler sections should therefore be based on a systematic procedure that can provide the necessary boundary conditions at the limits of its sub-processes. A rational method for the identification of the subprocesses of common types of polymer forming operations is described by Tadmor and Gogos (1979). [Pg.1]

In the case of, the energy is wrong because the molecular orbital is not a linear combination of atomic orbitals, it is approximated by a linear combination of atomic orbitals. Use of scaled atomic orbitals... [Pg.306]

Until World War 1 acetone was manufactured commercially by the dry distillation of calcium acetate from lime and pyroligneous acid (wood distillate) (9). During the war processes for acetic acid from acetylene and by fermentation supplanted the pyroligneous acid (10). In turn these methods were displaced by the process developed for the bacterial fermentation of carbohydrates (cornstarch and molasses) to acetone and alcohols (11). At one time Pubhcker Industries, Commercial Solvents, and National Distillers had combined biofermentation capacity of 22,700 metric tons of acetone per year. Biofermentation became noncompetitive around 1960 because of the economics of scale of the isopropyl alcohol dehydrogenation and cumene hydroperoxide processes. [Pg.94]

Approximately 50—55% of the product from a coal-tar refinery is pitch and another 30% is creosote. The remaining 15—20% is the chemical oil, about half of which is naphthalene. Creosote is used as a feedstock for production of carbon black and as a wood preservative. Because of modifications to modem coking processes, tar acids such as phenol and cresyUc acids are contained in coal tar in lower quantity than in the past. To achieve economies of scale, these tar acids are removed from cmde coal tar with a caustic wash and sent to a central processing plant where materials from a number of refiners are combined for recovery. [Pg.162]

The modem fermentation industries developed from the early era of antibiotics. Over 4000 antibiotics have been discovered since the 1950s. However, only about 100 are produced on a commercial scale and over 40 of these are prepared by a combination of microbial synthesis and chemical modifications. Antibiotics produced by fermentation and used as starting materials in chemical syntheses are given in Table 2. [Pg.178]

A similar technique to the Bureau of Mines trommel process called pellet flocculation has been used in Japan on a number of substrates on an industrial scale (47) using equipment made by the Ebara-Infilco Co. Combinations of inorganic salts such as lime with polyacrylamides are used as flocculants. [Pg.36]


See other pages where Combination of scales is mentioned: [Pg.111]    [Pg.239]    [Pg.432]    [Pg.402]    [Pg.94]    [Pg.295]    [Pg.76]    [Pg.296]    [Pg.408]    [Pg.111]    [Pg.239]    [Pg.432]    [Pg.402]    [Pg.94]    [Pg.295]    [Pg.76]    [Pg.296]    [Pg.408]    [Pg.723]    [Pg.74]    [Pg.246]    [Pg.1605]    [Pg.1716]    [Pg.472]    [Pg.137]    [Pg.418]    [Pg.443]    [Pg.565]    [Pg.712]    [Pg.1279]    [Pg.87]    [Pg.325]    [Pg.339]    [Pg.164]    [Pg.83]    [Pg.107]   


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