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Variables examining values

The system will be disturbed from the steady-state situation if any of the input variables changes value. Let us examine the following two situations ... [Pg.394]

Burner tests are complex, time-consuming, and expensive experiments. In the case of this category of experiments, one should always put a strong emphasis on the planning supported by statistical methods. Should the examined value be influenced by a low number of factors (< 3) and should the dependence between the values be known as linear, it is sufficient to use the so called factorial plan [29] for fhis fype of experiment, or a fractional factorial plan [29]. Nevertheless, most experiments are supposed to have a response variable without linear dependence on some of the factors, and it... [Pg.424]

In the maximum-likelihood method used here, the "true" value of each measured variable is also found in the course of parameter estimation. The differences between these "true" values and the corresponding experimentally measured values are the residuals (also called deviations). When there are many data points, the residuals can be analyzed by standard statistical methods (Draper and Smith, 1966). If, however, there are only a few data points, examination of the residuals for trends, when plotted versus other system variables, may provide valuable information. Often these plots can indicate at a glance excessive experimental error, systematic error, or "lack of fit." Data points which are obviously bad can also be readily detected. If the model is suitable and if there are no systematic errors, such a plot shows the residuals randomly distributed with zero means. This behavior is shown in Figure 3 for the ethyl-acetate-n-propanol data of Murti and Van Winkle (1958), fitted with the van Laar equation. [Pg.105]

The power law developed above uses the ratio of the two different shear rates as the variable in terms of which changes in 17 are expressed. Suppose that instead of some reference shear rate, values of 7 were expressed relative to some other rate, something characteristic of the flow process itself. In that case Eq. (2.14) or its equivalent would take on a more fundamental significance. In the model we shall examine, the rate of flow is compared to the rate of a chemical reaction. The latter is characterized by a specific rate constant we shall see that such a constant can also be visualized for the flow process. Accordingly, we anticipate that the molecular theory we develop will replace the variable 7/7. by a similar variable 7/kj, where kj is the rate constant for the flow process. [Pg.87]

Knoop developed an accepted method of measuring abrasive hardness using a diamond indenter of pyramidal shape and forcing it into the material to be evaluated with a fixed, often 100-g, load. The depth of penetration is then determined from the length and width of the indentation produced. Unlike WoodeU s method, Knoop values are static and primarily measure resistance to plastic flow and surface deformation. Variables such as load, temperature, and environment, which affect determination of hardness by the Knoop procedure, have been examined in detail (9). [Pg.9]

It is useful to examine the combustion process appHed to soHd wastes as fuels and sources of energy. AH soHd wastes are quite variable in composition, moisture content, and heating value. Consequendy, they typically are burned in systems such as grate-fired furnaces or duidized-bed boilers where significant fuel variabiUty can be tolerated. [Pg.56]

Let us examine how one determines the values of the inductor and capacitor. Several assumptions have to be made at the beginning of the design process since several of the tank circuit s characteristics are variable within the application. The first is to assume a value for the Q of the tank circuit. In the application, the Q varies greatly with the amount of load placed on the output of the supply. So, a good value to start with is... [Pg.158]

If V is a function of more than one variable, then more complex criteria for determining maxima and minima are obtained. Generally, but not always, the second partial derivatives of the function with respect to all its variables are sufficient to determine the character of a stationary value of V. For such functions, the theory of quadratic forms as described by Langhaar [B-1] should be examined. [Pg.483]

The examination of this model and results of numerical solutions indicate that ignition propagation is determined by the absolute value and variation of heat transfer along the surface of the grain, both before and after the first instant of ignition on the grain surface. Therefore, the important variables are (1) igniter flow rate, (2) port diameter, (3) gas temperature, (4) gas composition, and (5) motor pressure. [Pg.27]

In Figure 8.2, for the purpose of examining the effeet of variable calcium, the Sr/Ca ratios of all the plants were set to the same fixed value (0.00790). In nature this situation is rarely likely to exist because there is intrinsic vari-abihty among different plant species (Runia 1987, 1988). The fact that bone represents a long-term (ca. 7 years) dietaiy average somewhat obviates this somce of variability. To the extent, however, that the dietaiy selection of plants varies systematically, the dietary Sr/Ca ratio will reflect this difference. Consistent dietaiy differences in the selection of plants are likely to affect bone Sr/Ca, especially since plants will usually be the dominant source of calcium. It should be noted that one of the earliest paleodietary apphcations of bone... [Pg.164]

For a selected dependent variable and for each of the 2 possible test conditions, have each scientist provide an estimate (prediction) of the numerical value of the dependent variable that would be expected if the test combination were included in the final experimental design This assignment is usually the most difficult task the individual scientist is required to perform Because of the difficulty, the task is typically continued as a week-long assignment to permit each scientist to assemble data, refer to literature, examine previous experimental results, etc ... [Pg.70]

It is important to realize that the number of contrasts increases with the square of the number of variables (n or p). Some contrasts, however, are more important than others and many of them are linearly dependent. To evaluate the importance of a contrast we have to examine the distances and (Figs. 31.3a and b). If these are large in comparison to others, then the corresponding contrasts are more important. Of course, a distance of zero means that the contrasts are non-existent, i.e. the corresponding rows or columns in X are identical or differ only by a constant value. [Pg.115]

As a part of logistic regression analysis, odds ratio plots are an excellent way to see how much more likely a condition is to exist based on the presence of another condition. Just by glancing at an odds ratio plot, you can see whether an independent variable is significant to the dependent variable. For instance, if the odds ratio confidence interval does not cross the value of 1, then the independent variable odds ratio is significant. Examine the following graph. [Pg.203]

Thus, the solution of the MILP problem is started by solving the first relaxed LP problem. If integer values are obtained for the binary variables, the problem has been solved. However, if integer values are not obtained, the use of bounds is examined to avoid parts of the tree that are known to be suboptimal. The node with the best noninteger solution provides a lower bound for minimization problems and the node with the best feasible... [Pg.51]


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See also in sourсe #XX -- [ Pg.276 ]

See also in sourсe #XX -- [ Pg.276 ]




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Examining the Values of Variables

Variable value

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