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Design predictive models

The objectives functions used to generate the results are quite simple in its essence. Every prescribed internal profile compared with the factorial design prediction model gives a deviation error. The sum of these deviations completes the objective function. [Pg.693]

The MPC control problem illustrated in Eqs. (8-66) to (8-71) contains a variety of design parameters model horizon N, prediction horizon p, control horizon m, weighting factors Wj, move suppression factor 6, the constraint limits Bj, Q, and Dj, and the sampling period At. Some of these parameters can be used to tune the MPC strategy, notably the move suppression faclor 6, but details remain largely proprietary. One commercial controller, Honeywell s RMPCT (Robust Multivariable Predictive Control Technology), provides default tuning parameters based on the dynamic process model and the model uncertainty. [Pg.741]

Rotating machinery usually performs efficiently if it works under design point conditions. However, off-design conditions require a predictive model of the machine s performance. In a FCC power train system, mass flow deviation is quite common for adjusting production capacity to meet the requirements of petrochemical product markets. [Pg.464]

The National Bureau of Standards has a unique role to play in supporting the field of chemical engineering. It should be the focal point for providing evaluated data and predictive models for data to facilitate the design, the scale-up, and even the selection of chemical processes for specific applications. [Pg.209]

M.J. 1996 A predictive model for animal 8"0 explaining old studies and designing new... [Pg.138]

PREDICTIVE MODELS FOR BETTER DECISIONS FROM UNDERSTANDING PHYSIOLOGY TO OPTIMIZING TRIAL DESIGN... [Pg.529]

I/O data-based prediction model can be obtained in one step from collected past input and output data. However, thiCTe stiU exists a problem to be resolved. This prediction model does not require any stochastic observer to calculate the predicted output over one prediction horiajn. This feature can provide simplicity for control designer but in the pr ence of significant process or measurement noise, it can bring about too noise sensitive controller, i.e., file control input is also suppose to oscillate due to the noise of measursd output... [Pg.861]

In this work, therefore we aim to combine the stochastic observer to input/output prediction model so that it can be robust against the influence of noise. We employ the modified I/O data-based prediction model [3] as a linear part of Wimra" model to design the WMPC and these controllers are applied to a continuous mefihyl methacrylate (MMA) solution polymerization reactor to examine the performance of controller. [Pg.861]

As mentioned above, the backbone of the controller is the identified LTI part of Wiener model and the inverse of static nonlinear part just plays the role of converting the original output and reference of process to their linear counterpart. By doing so, the designed controller will try to make the linear counterpart of output follow that of reference. What should be advanced is, therefore, to obtain the linear input/output data-based prediction model, which is obtained by subspace identification. Let us consider the following state space model that can describe a general linear time invariant system ... [Pg.862]

This incranental prediction model should be converted into the output prediction form so that it can be used for the design of controller i.e.,... [Pg.863]

Fig. 1 illustrates the identification result, i.e., validation of identified model. The 4-level pseudo random signal is introduced to obtain the excited output signal which contains the sufficient information on process dynamics. With these exciting and excited data, L and Lu as well as state space model are oalcidated and on the basis of these matrices the modified output prediction model is constructed according to Eq. (8). To both mathematical model assum as plimt and identified model another 4-level pseudo random signal is introduced and then the corresponding outputs fiom both are compared as shown in Fig. 1. Based on the identified model, we design the controller and investigate its performance under the demand on changes in the set-points for the conversion and M . The sampling time, prediction and... Fig. 1 illustrates the identification result, i.e., validation of identified model. The 4-level pseudo random signal is introduced to obtain the excited output signal which contains the sufficient information on process dynamics. With these exciting and excited data, L and Lu as well as state space model are oalcidated and on the basis of these matrices the modified output prediction model is constructed according to Eq. (8). To both mathematical model assum as plimt and identified model another 4-level pseudo random signal is introduced and then the corresponding outputs fiom both are compared as shown in Fig. 1. Based on the identified model, we design the controller and investigate its performance under the demand on changes in the set-points for the conversion and M . The sampling time, prediction and...
Predictive modeling [38], Tachugi design principles [2], Monte Carlo simulations to simulate impacts of different product and process conditions on Q attribute level [40]... [Pg.564]

Until about the second World War chemical processes were developed in an evolutionary way by building plants of increasing size and capacity. The capacity of the next plant in the series was determined by a scale-up factor that depended mainly upon experience gained from scale-ups of similar plants. Due to a lack of predictive models for chemical processes and operations, processes had to be scaled up in many small steps. This procedure was very expensive and the results unreliable. Therefore, large safety margins were incorporated in scale-up procedures, which often resulted in a significant unintended overcapacity of the designed plant. [Pg.194]

EPA Exposure Assessment Workshops - Level I and II. In April 1982, the EPA Office of Research and Development (ORD) organized two workshops designed to assess and identify current techniques (i.e., data, protocols, predictive models) used in performing exposure assessments, enumerate technical information gaps, and recommend prioritized research topics to satisfy current and anticipated needs. The Level I workshop was comprised of... [Pg.153]

As discussed in other chapters of this book, two-phase flows of gas and particles occur with different flow regimes. The mechanisms for heat transfer and the resulting heat transfer coefficients are strongly affected by the different flow characteristics, resulting in different design correlations and predictive models for each flow regime. This chapter will deal with the two most often encountered flow regimes ... [Pg.154]

Arches with the same conformation tend to have similar amino acid sequence patterns for key apolar, polar, or glycine residues (Hennetin et al., 2006). At the same time, the sequence patterns of the various kinds of arches differ in a characteristic manner (Fig. 12) and this information may be helpful for the prediction, modeling, and de novo design of /2-solenoids. [Pg.80]


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See also in sourсe #XX -- [ Pg.503 ]




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