Closed-loop algorithm

Results for ratios of delays indicate that proportional loss differentiation (i.e., schedule cancellation) is achieved when the outbound route is overloaded and traffic is dropped. However, it is not met in any of the algorithms when the queue falls to 0. This implies that the algorithms basically manipulate the queue of the flow members and scheduling of the members to meet the relative delay and loss guarantees. With this the REP feedback loops used in the closed-loop algorithm appear to be robust to variations in the offered load, and the results of the REP closed-loop algorithm are found to be better than the one without any shift. 

Remember, as long as the real robot s sensors and motors respond similarly to the simulator, then closed-loop algorithms developed for the simulator generally work with the real robot with minimal, if any, modification. Even if there are significant differences between the simulation and the real robot, an algorithm developed on the simulation is far easier to fine-tune with the real robot than developing the entire algorithm fi om scratch. 

Foxboro developed a self-tuning PID controller that is based on a so-called expert system approach for adjustment of the controller parameters. The on-line tuning of K, Xi, and Xo is based on the closed-loop transient response to a step change in set point. By evaluating the salient characteristics of the response (e.g., the decay ratio, overshoot, and closed-loop period), the controller parameters can be updated without actually finding a new process model. The details of the algorithm, however, are proprietary... 

In the present study, we propose a tuning method for PID controllers and apply the method to control the PBL process in LG chemicals Co. located in Yeochun. In the tuning method proposed in the present work, we first find the approximated process model after each batch by a closed-loop Identification method using operating data and then compute optimum tuning parameters of PID controllers based on GA (Genetic Algorithm) method. 

The outputs of the sensors were used in two closed-loop control strategies developed for combustor performance optimization [7]. The objective of the first strategy, based on an adaptive least-mean squares (LMS) algorithm, was to maximize the magnitude and coherence of temperature oscillations at the forcing frequency /o in the measured region. The LMS algorithm was used to determine... 

Figure 24.12 Measured Trms values (a) for successive feedback control steps during closed-loop control of the 50-kilowatt forced combustor at China Lake, feedback was based on a simplex hill-climbing algorithm which is adjusting the phase between the primary and secondary air drivers to maximize Trms values (6) illustrates representative power spectra with and without control...

A closed-loop system with feedback, which is illustrated in Figure 13.2, is the central feature of a control system in bioprocess control, as well as in other processing industries. First, a set-point is established for a process variable. Then, the process variable measured in a bioreactor is compared with the set-point value to determine a deviation e. Based on the deviation, a controller uses an algorithm to calculate an output signal O that determines a control action to manipulate a control variable. By repeating this cycle during operation, successful process control is performed. The controller can be the operator when manual control is being employed. 

Fig. 6. A closed loop apparatus for optimally identifying quantum Hamiltonian information. The closed loop operations aim to reveal one or more control experiments that identify the best quality Hamiltonian information. Hamiltonian quality is used as the feedback signal for the learning algorithm guiding the laboratory experiments.

There is a variety of specifications that can be imposed on the system closed-loop response for a given change in set point. These lead to a number of alternative discrete-time control algorithms—the best known of which are the Deadbeat and Dahlin s algorithms. 

DAHLIN<44) suggested that, in order to avoid the large overshoots and oscillatory behaviour which are characteristic of the deadbeat algorithm, the specification of the system closed-loop response to a step change in set point should be the same as that for a first-order system with dead time. The first-order time constant can then be employed as a design parameter which can be adjusted to give the desired closed-loop response. Hence ... 

We have also performed experiments using an open-plus-closed-loop control technique [156] and adaptive control algorithm [157] to steer the system from... 

A Simulation Study on the Use of a Dead-Time Compensation Algorithm for Closed-Loop Conversion Control of Continuous Emulsion Polymerization Reactors... 

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