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Variables final values

The most often used subphase is water. Mercury and otlier liquids [12], such as glycerol, have also occasionally been used [13,14]. The water has to be of ultrapure quality. The pH value of tire subphase has to be adjusted and must be controlled, as well as tire ion concentration. Different amphiphiles are differently sensitive to tliese parameters. In general it takes some time until tire whole system is in equilibrium and tire final values of pressure and otlier variables are reached. Organic contaminants cannot always be removed completely. Such contaminants, as well as ions, can have a hannful influence on tire film preparation. In general, all chemicals and materials used in tire film preparation have to be extremely pure and clean. [Pg.2611]

Initial and final temperature and feed rate are taken as parameters to be optimized, whereby the other variables are optimized in the same run. Temperature and feed rate between these two points are assumed to be straight lines connecting the initial and final values. The optimal values of variables obtained in the first step are taken as initial guesses for optimization. [Pg.326]

The rate of change /Final value - Instantaneous value of the variable / Time constant /... [Pg.89]

We now take a formal look at the steady state error (offset). Let s consider a more general step change in set point, R = M/s. The eventual change in the controlled variable, via the final value theorem, is... [Pg.95]

There are two noteworthy items. First, the closed-loop system is now second order. The integral action adds another order. Second, the system steady state gain is unity and it will not have an offset. This is a general property of using PI control. (If this is not immediately obvious, try take R = 1/s and apply the final value theorem. We should find the eventual change in the controlled variable to be c (°°) =1.)... [Pg.97]

In these equations, x is the instantaneous value of any control variable at any space or time t.x0 is the initial value and xF is the final value of the control variable. In principle, x can be any control variable such as temperature, reactant feed rate, evaporation rate, heat removed or supplied, and so on. tfotai is the total distance or time for the profile. The convexity and concavity of the curves are governed by the values of a and a2. Figures 3.14a and b illustrate typical forms of each curve. [Pg.47]

The number of binary variables for both the MILP and MINLP was 112 with 4 time points. The solution was found in 0.89 CPU seconds using the same processor as in the previous example. The objective function had a final value of 3684.61 kg of water. If wastewater recycle/reuse had not been considered the amount of effluent would have been 4274.40 kg, thus a wastewater reduction of 13.8% is achieved. The value of objective function for MILP and MINLP were not the same in this case, which means the final solution obtained is not globally optimal (Gouws et al., 2008). The value of the objective function from the MILP was only marginally lower being 3678.84 kg. [Pg.215]

If the flowchart P has a loop-free graph - if P is a tree - then the construction of W(P,A,B) is now quite simple. If P is loop-free there are only a finite number of paths 0, ...,on from START to STOP which are consistent and hence execution sequences. The input condition A(X) is a function only of the inputs, of course, while the output condition B(X,Y) can be regarded as a function of the input and of the final values of all the program variables (some of these values, of course, may play no role in the statement of the condition). Notice that under these conditions, when is a complete execution sequence from START to STOP, the path verification condition VCPjO AB, ) for any interpretation I is a function of the input X alone. [Pg.158]

Observe that the new statement first stores all global values which are not actual parameters Cy, ...,ym) on the pushdown store, then puts label Lq on top of the pushdown store, and finally lets the values of the actual parameters of the call, v, ...,vn, specify the formal parameters of procedure F, x,, ...,x the x. will be used as variables in the execution of F. Then con-trol passes to the start of the procedure body of F. When F is completed, label Lq r will be retrieved from the top of the store and a GOTO will pass control to the statement labeled by Lq. Then each actual parameter of the call, v, will be respecified by the final value of the corresponding formal parameter, x, of F, the other global variables will have their proper values restored from the pushdown store and control will return to , the statement originally following . ... [Pg.272]

There are several ways of cleaning this up. We now present just one. We notice that part of the problem is that procedures are really kinds of programs which we verify separately. In our main verification procedure, we demanded that the input variables be unchanged during the whole program, in order to be able to make clean statements about the relationship between the final values of output variables with the initial values of input variables. One of our difficulties is that we have not done this for procedures. Let us see how we can do it ... [Pg.288]

A state function is a variable that defines the state of a system it is a function that is independent of the pathway by which a process occurs. Therefore, the change in a state function depends only on the initial and the final value, not on how that change occurred. [Pg.237]

Each value in the final column of the table constructed above is now divided by 4, which is the number of additions or subtractions made in each column. The results of this division show the numerical effects of each variable and the interaction between variables. The value opposite the second row shows the effect of the temperature, the third shows the effect of the slag phase composition, and, the fifth the effect of the metal composition. The interaction terms then follow the symbols of each row, the fourth showing the effect of... [Pg.366]

The generators of a Lie group are defined by considering elements infinitesimally close to the identity element. The operator T(a)x —t x takes variables of space from their initial values x to final values x as a function of the parameter a. The gradual shift of the space variables as the parameters vary continuously from their initial values a = 0 may be used to introduce the concept of infinitesimal transformation associated with an infinitesimal operator P. Since the transformation with parameter a takes x to x the neighbouring parameter value a + da will take the variables x to x + dx, since x is an analytical function of a. However, some parameter value da very close to zero (i.e. the identity) may also be found to take x to x + dx. Two alternative paths from x to x + dx therefore exist, symbolized by... [Pg.86]

On the other hand, if more process variables whose values are unknown exist in category 2 than there are independent equations, the process model is called underdetermined that is, the model has an infinite number of feasible solutions so that the objective function in category 1 is the additional criterion used to reduce the number of solutions to just one (or a few) by specifying what is the best solution. Finally, if the equations in category 2 contain more independent equations... [Pg.15]

Table 10.10 shows the performance of the evolutionary solver on this problem in eight runs, starting from an initial point of zero. The first seven runs used the iteration limits shown, but the eighth stopped when the default time limit of 100 seconds was reached. For the same number of iterations, different final objective function values are obtained in each run because of the random mechanisms used in the mutation and crossover operations and the randomly chosen initial population. The best value of 811.21 is not obtained in the run that uses the most iterations or computing time, but in the run that was stopped after 10,000 iterations. This final value differs from the true optimal value of 839.11 by 3.32%, a significant difference, and the final values of the decision variables are quite different from the optimal values shown in Table 10.9. [Pg.407]

A Parametric Plot choosing the final value can be used to find the influence of one variable on the steady state. The second parameter can be changed in the Parameter Window and additional parametric runs made and plotted with an overlay plot. Thus it is possible to obtain a sort of contour plot with a series of curves for values of the second parameter. Unfortunately, no automatic contour plot is yet possible. [Pg.600]

A crystallographic example of optimization would be the minimization of a least-squares or a negative log-likelihood residual as the objective function, using fractional or orthogonal atomic coordinates as the variables. The values of the variables that optimize this objective function constitute the final crystallographic model. However, due to the... [Pg.156]

Intermediate secondary measurements, y Dependent variables whose values are recorded by sensors used in the process. These variables are indirect indicators of final product quality as such, they should be useful in predicting autoclave curing outcomes. [Pg.283]

In the original formulation, u(6) - fid was to have been maximized, but to conform to the theorem, we minimize its negative. The final values of the adjoint variables are... [Pg.72]

The normal function of any control system is to ensure that the controlled variable attains its desired value as rapidly as possible after a disturbance has occurred, with the minimum of oscillation. Determination of the response of a system to a given forcing function will show what final value the controlled variable will attain and the manner in which it will arrive at that value. This latter is a function of the stability of the response. For example, in considering the response of a second order system to a step change, it can be seen that oscillation increases... [Pg.612]

Finally, the thermodynamic properties of a system considered as variables may be classified as either intensive or extensive variables. The distinction between these two types of variables is best understood in terms of an operation. We consider a system in some fixed state and divide this system into two or more parts without changing any other properties of the system. Those variables whose value remains the same in this operation are called intensive variables. Such variables are the temperature, pressure, concentration variables, and specific and molar quantities. Those variables whose values are changed because of the operation are known as extensive variables. Such variables are the volume and the amount of substance (number of moles) of the components forming the system. [Pg.4]

Model AT = a0 + aAxT + a2x OO + a3x M + a4xT x M + asxT x 00 Dependent variable AT Loss function ([OBS-PRED]2)/S2experim Final value of loss function 0.117 R2 0.97... [Pg.179]


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See also in sourсe #XX -- [ Pg.58 ]




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