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Coefficient, input-output

To identify the fuzzy models for reaction rates and diffusion coefficient, input-output data are required. The inputs can be obtained from the simulation model. However, the ontputs Ri pi,p4,T), R2(PhPA,T), R ,iPi,P4,T) and >(7)) of the fuzzy models caimot be readily obtained. The outputs are therefore derived from observed behavior by Pl-estimation (van Lith et al., 2001). The reaction rates and diffusion coefficient can be estimated with the help of the mass balances of species of the hybrid model and the steady state profiles from the identification experiments. The estimators were tuned manually by comparing the concentration profiles with the reference values from the simulation model. [Pg.431]

Develop via mathematical expressions a valid process or equipment model that relates the input-output variables of the process and associated coefficients. Include both equality and inequality constraints. Use well-known physical principles (mass balances, energy balances), empirical relations, implicit concepts, and external restrictions. Identify the independent and dependent variables (number of degrees of freedom). [Pg.742]

Mathematical models based on physical and chemical laws (e.g., mass and energy balances, thermodynamics, chemical reaction kinetics) are frequently employed in optimization applications (refer to the examples in Chapters 11 through 16). These models are conceptually attractive because a general model for any system size can be developed even before the system is constructed. A detailed exposition of fundamental mathematical models in chemical engineering is beyond our scope here, although we present numerous examples of physiochemical models throughout the book, especially in Chapters 11 to 16. Empirical models, on the other hand, are attractive when a physical model cannot be developed due to limited time or resources. Input-output data are necessary in order to fit unknown coefficients in either type of the model. [Pg.41]

Having set up the expanded reproduction schema in an input-output format, the path is now clear for it to be modelled as a multiplier framework. To achieve this aim, input coefficients ay = Xy/Xj specify the ratio between physical flows of means of production (Xy), from department i to department j, to (physical) gross output (Xy) of department j. In Marx s reproduction schema, these input coefficients are applied to Department 1, the only sector producing means of production. For Department 2, different notation is required for our multiplier framework. Ratios to gross output of the total number of labour units employed in each sector (Ly) are represented by labour coefficients ly = Lj/Xy, and consumption coefficients ht = BJL are... [Pg.17]

These coefficients are derived from Table 4.3a, the input-output formulation of Marx s reproduction schema. [Pg.45]

Assuming that a linear approximation can be made for the correlation between the sectoral employment level and the sectoral production level, the quantitative impacts on employment are calculated using job coefficients. Of course, the constant input-output coefficients are a strong assumption and could be criticised (Zhang and Folmer, 1998). However, structural effects could be analysed in a ceteris-paribus analysis with the chosen approach. [Pg.538]

Constraints (5.13) and (5.14) represent the material balance that governs the operation of the petrochemical system. The variable x 1 represents the annual level of production of process m Mpa where ttcpm is the input-output coefficient matrix of material cp in process m Mpel. The petrochemical network receives its feed from potentially three main sources. These are, (i) refinery intermediate streams of an intermediate product cir RPI, (ii) refinery final products Ff ri of a final product cfr RPF, and (iii) non-refinery streams Fn px of a chemical cp NRF. For a given subset of chemicals cp CP, the proposed model selects the feed types, quantity and network configuration based on the final chemical and petrochemical lower and upper product demand Dpet and DPet for each cp CFP, respectively. In constraint (5.15), defining a binary variable yproc et for each process m Mpet is required for the process selection requirement as yproc et will equal 1 only if process m is selected or zero otherwise. Furthermore, if only process m is selected, its production level must be at least equal to the process minimum economic capacity B m for each m Mpet, where Ku is a valid upper... [Pg.98]

The annual production of HT materials depends on the type of FIT technologies. Taking into account the highest input —> output mass transfer coefficient of each process, the following masses of HT materials would theoretically be produced in Switzerland ... [Pg.399]

There is a much more important consideration than how to plot the absorption coefficients. That is whether the overall operation of the visual system is even remotely linear. If it is not, the signal related to the quanta out may not be related in any linear way to the quanta in and the above subtlety of how to plot the data becomes trivial. The actual problem is how to define the input-output characteristic of the visual system. [Pg.45]

Group the following words in sets of synonyms (1) response, (2) input variable, (3) parameter, (4) state variable, (5) system parameter, (6) initial condition, (7) output, (8) independent variable, (9) dependent variable, (10) coefficient, (11) output variable, (12) constant. [Pg.644]

In order to perform these steps with a minimum of input-output operations one has to keep all matrices A in high-speed memory. Furthermore, the coupling coefficients should be ordered according to the label i. Then, if all for a given i can be kept in core, a single read of these coefficients is sufficient to calculate the Gj) for all i j. For applications with up to 8-10 active orbitals, the memory requirement to perform these steps is not exceedingly large, in particular if molecular symmetry can be used. Note that the crucial step is the matrix multiplication in Eq. (234) and this can be perfectly vectorized. [Pg.56]

The intent here is to give only a brief summary of the methodology by which the studies were carried out. Briefly, input-output analysis was the basic tool used. The economy was modeled as a steady state, full employment economy for 1975 and 1978 for the corrosion and fracture studies respectively. The economy was broken down into 130 sectors for the corrosion study and 150 sectors for fracture study. In both cases, capital equipment was treated as an input into production rather than a part of final demand as normally done. Having established the steady state for the chosen year for the world as it is (World I), steady state World II (corrosion or fracture free world) and World III (best practical world) were established. Final demand and the coefficients in the transactions matrix and the flow and stock capital matrices were changed as appropriate. In the case of the flow matrix, changes in the coefficients by column were collected in a special "social savings row. This precluded the necessity to renormalize the coefficients and gave a convenient way for... [Pg.388]

Attenuation coefficient Input optical power Output optical power Fiber length... [Pg.111]

Forecasting. The major corporate use of input-output analysis has been in providing forecasts of the U.S. economy and forecasts of changes in the coefficients of the direct- and total-requirements tables. Forecasts have been used in identifying acquisition and diversification opportunities. Studying the effect of changes in final demand for automobiles on the CPI is one such forecasting application of input-output analysis. [Pg.154]

Changes in technology can often be incorporated into an input-output analysis by estimating new direct coefficients for a specific industry or industries. Once a new D matrix has been estimated, the T matrix can be found by inverting I - D. However, often it is inconvenient or too expensive to perform the inversion. This problem considers two ways in which changes in the T matrix can be estimated with a new D matrix. [Pg.158]

As already mentioned, compensation and calibration methods may be used to improve the accuracy of the output signal. From Figure 3.8a and b and Eqs. 3.11— 3.14, it is obvious that a sensitivity or an offset error can be calibrated by identifying the input/output characteristics at a single point of the transfer function at several temperatures the appropriate temperature coefficients can then be deduced. In case of a superposition of sensitivity and offset deviations, calibration can also be done by measuring the input/output characteristic at at least two points. [Pg.37]

U Input/Output An initial set of MO coefficients if initial.scf = NO. On output final MO coefficients. [Pg.600]

Although there is a large literature on identifiability for linear systems with constant coefficients, less has been done on nonlinear systems. Two general properties should be remembered. Whereas for linear systems one can substitute impulsive inputs for the experimental inputs for die analysis of identifiability, one cannot do that for nonlinear systems. One must analyze the input-output experiment for the actual inputs used. That is a drawback. On the other hand, experience shows dial frequently the introduction of nonlinearities makes a formerly nonidentifiable model identifiable for a given input-output experiment. Two methods are available. [Pg.317]

Two methods were employed for the specification of transitions (1) input/output relations, that is, introducing coefficients that represent the intmolations of the flow quantities (2) defining the relations between input and output flows by a set of mathematical... [Pg.71]

The influence coefficient of each factor refers to input-output complete consumption coefficient table in China (Henan Provincial Bureau of Statistics, 2005). According to the formula ... [Pg.680]

An increase of the linear flow rate of a reaction mixture creates optimal values of the characteristic mixing times of liquid flows, turbulent diffusion coefficients, and dissipation of the specific kinetic energy of turbulence. The upper limit of application of tubular turbulent devices (based on dynamic characteristics of their operation) is evidently the input-output pressure drop in accordance with Ap V, while the lower limit will be determined by the values of the turbulent diffusion coefficient ... [Pg.46]

A cylindrical device is characterised by similar input and output pressures (Figure 2.36) the input-output pressure drop is low in this case, not exceeding 0.03 atmospheres under experimental conditions. Quantitative correlations between pressure in a tubular turbulent device and the reaction mixture flow rate R is the correlation coefficient) [45, 97] ... [Pg.87]


See other pages where Coefficient, input-output is mentioned: [Pg.11]    [Pg.18]    [Pg.30]    [Pg.118]    [Pg.83]    [Pg.417]    [Pg.11]    [Pg.310]    [Pg.124]    [Pg.612]    [Pg.129]    [Pg.83]    [Pg.34]    [Pg.19]    [Pg.214]    [Pg.1207]    [Pg.8]   


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Coefficient, input-output direct

Coefficient, input-output total

Input-output coefficient matrix

Input/output

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