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Tool controlling parameters

To clarify the selection of a particular MLR system (ILR, 2LR, or 3LR system) a comparison in terms of process complexity, resolution, aspect ratio, linewidth tolerance, sensitivity and effort required for research and development will be given. Then a comparison between deep-UV and RIE PCM systems in terms of resolution, aspect ratio, substrate patterning processes allowed, temperature stability, resist removal at the alignment sites, tool-controlling parameters, and tool cost will be included. [Pg.342]

The selection of the PID controller parameters K, T[ and can be obtained using the classical control system design techniques described in Chapters 5 and 6. In the 1940s, when such tools were just being developed, Ziegler and Nichols (1942) devised two empirical methods for obtaining the controller parameters. These methods are still in use. [Pg.90]

Integral error criteria are ideally suited to simulation applications since only one additional program statement is required for the simulation. The optimal control parameters Kp, Tj and Xq can be then found at minimal ITAE. For this, it is useful to be able to apply the available optimisation tools implemented in such programs as MATLAB, SIMUSOLV and ESL. [Pg.105]

Research users need full access to the functional elements of the spectrometer system and require the most efficient and flexible tools for MR sequence and application development. If the measurement methods delivered with the software do not adequately address the specific investigational requirements of a research team, modem NMR software is an open architecture for implementing new and more sophisticated functionality, with full direct access to all hardware controlling parameters. After evaluation, the new functionality can be developed with the help of toolbox functions that allow rapid prototyping and final builds, to enable the new sequence to be executed by non-experienced personnel and then used in routine applications. These toolboxes provide application oriented definitions and connect to standard mechanisms and routine interfaces, such as the geometry editor, configuration parameters or spectrometer adjustments. [Pg.57]

After the series of metabolic pathways had been elucidated for the three model compounds 1-3, these data were implemented into the mathematical model PharmBiosim. The nonlinear system s response to varying ketone exposure was studied. The predicted vanishing of oscillatory behavior for increasing ketone concentration can be used to experimentally test the model assumptions in the reduction of the xenobiotic ketone. To generate such predictions, we employed as a convenient tool the continuation of the nonlinear system s behavior in the control parameters. This strategy is applicable to large systems of coupled, nonlinear, ordinary differential equations and shall together with direct numerical simulations be used to further extend PharmBiosim than was sketched here. This model already allows more detailed predictions of stereoisomer distribution in the products. [Pg.83]

In the above definitions, 9 represents a set of parameters of the system, having constant values. These parameters are also called control parameters. The set of the system s variables forms a representation space called the phase space [32]. A point in the phase space represents a unique state of the dynamic system. Thus, the evolution of the system in time is represented by a curve in the phase space called trajectory or orbit for the flow or the map, respectively. The number of variables needed to describe the system s state, which is the number of initial conditions needed to determine a unique trajectory, is the dimension of the system. There are also dynamic systems that have infinite dimension. In these cases, the processes are usually described by differential equations with partial derivatives or time-delay differential equations, which can be considered as a set of infinite in number ordinary differential equations. The fundamental property of the phase space is that trajectories can never intersect themselves or each other. The phase space is a valuable tool in dynamic systems analysis since it is easier to analyze the properties of a dynamic system by determining... [Pg.45]

A key factor in modeling is parameter estimation. One usually needs to fit the established model to experimental data in order to estimate the parameters of the model both for simulation and control. However, a task so common in a classical system is quite difficult in a chaotic one. The sensitivity of the system s behavior to the initial conditions and the control parameters makes it very hard to assess the parameters using tools such as least squares fitting. However, efforts have been made to deal with this problem [38]. For nonlinear data analysis, a combination of statistical and mathematical tests on the data to discern inner relationships among the data points (determinism vs. randomness), periodicity, quasiperiodicity, and chaos are used. These tests are in fact nonparametric indices. They do not reveal functional relationships, but rather directly calculate process features from time-series records. For example, the calculation of the dimensionality of a time series, which results from the phase space reconstruction procedure, as well as the Lyapunov exponent are such nonparametric indices. Some others are also commonly used ... [Pg.53]

Development and improvement of methods and tools to control parameters regulated by criticality safety ... [Pg.46]

Value parameters enable to solve one of important problems in the theory of optimal control, namely to perform the preliminary selection among the tools of impact on a chemical process. It is easy to select the most effective and feasible control parameter, considering the time behavior of value contributions for the species and individual steps for several values of u(0 from the interval (4.26). In this case the eontrol parameter acts intensively on the reaction through influencing the rate of the 7-th step or the accumulation rate of the /-th species having ponderable contributions. [Pg.73]

Now the problem of optimal control may be solved more strictly by preliminary selecting as control parameters the rate constants for steps (3) and (4), influencing positively on the selectivity. Obviously, by controlling the rate constants of steps it should be understood the application of experimental tools that have an influence upon these parameters, for example, using the appropriate catalysts. [Pg.125]

The safety analysis should support safe operation of the plant by serving as an important tool in developing and confirming plant protection and control system set points and control parameters. It should also be used to establish and validate the plant s operating specifications and limits, normal and off-normal operating procedures, maintenance and inspection requirements, and normal and emergency procedures. [Pg.32]

To obtain the maximum value of K, various design, materials, processing, tooling, and quality control parameters have to be optimized. To obtain the minimum coefficient of variation, either the part or the testing process must be reproducible, with minimal deviation and scatter. Note that obtaining a low CV does not automatically mean that the average value X is maximal or optimal. [Pg.312]

Process control—for a given dryer and a specified vector of input and control parameters the output parameters at a given instance are sought. This is a special case when not only the accuracy of the obtained results but the required computation time is equally important. Although drying is not always a rapid process, in general for real-time control, calculations need to provide an answer almost instantly. This usually requires a dedicated set of computational tools like neural network models. [Pg.73]


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Control parameters

Controlling parameter

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