Auto-control systems

Control systans, in their broadest sense, include sensors, plant status indications, logic systans, alarm systems, and auto-control systems. With process plant digital systans, the control systems are usually referred to as the digital or distributed control systan (DCS). The DCS includes the human-machine interface (HMI) - the computa screens in the main control room - for the normal operation of the plant. The functions of the DCS are self-evidently to control the plant parameters within normal limits, and to advise the operators of plant status, and to raise alarms when normal parameter ranges are exceeded. 

Auto-control systems can initiate faults if they fail. This can lead to plant downtime, and also to challenges on the protection systems, i.e., they can cause initiating events in fault sequences. It is therefore common to implement duplex control systems which can achieve SIL 2 reliability (10 pfd or pa). 

G. E. Open Pool Reactor Manual, Chapters 8, 17, 18 Auto Control System... 

NRC95) UWNR OTM, Controls Instrumentation III, Auto Control System SAR, Section 7.3, p.7-8... 

Vanyukov process has been used for decades, and OSBS process has also been applied for above ten years. Lots of experience on industrial production has accumulated on oxidative smelting, reductive smelting, consecutive operation and periodical operation. The furnace itself and its auxiliary equipments, including waste heat boiler, oxygen production, water recycle system, auto control system, have normative design, produetion and installation procedures. 

INFICON s Auto Control Tune is based on measurements of the system response w/ith an open loop. The characteristic of the system response is calculated on the basis of a step change in the control signal. It is determined experimentally through two kinds of curve accordance at two points. This can be done either quickly w/ith a random rate or more precisely with a rate close to the desired setpoint. Since the process response depends on the position of the system (in our case the coating growth rate), it is best measured near the desired virork point. The process information measured in this vray (process amplification Kp, time constant T., and dead time L) are used to generate the most appropriate PID control parameters. 

Hydrocarbon Trap System. The concept of a hydrocarbon trap or adsorber system is based on molecular sieve hydrocarbon adsorber systems. The temperatures at which hydrocarbon adsorption takes place exist in the auto engine exhaust system during the period of cold start of an automobile when the catalytic control system has not yet reached functional temperature. Zeolites have been reportedly useful for hydrocarbon adsorption (53,169). Zeolites desorb hydrocarbons at temperatures of 400°C, ie, once the catalytic control system is functional. Therefore, hydrocarbons adsorbed by the zeolite can also be desorbed then oxidized by a catalyst. Methods to accomplish cold start hydrocarbon adsorption, heatup of the main catalyst, and desorption have been identified. Some of these systems use exhaust pipe valves to divert the exhaust gases to the hydrocarbon trap for the low temperature portion, and by-pass the gases around the trap after the main catalyst has heated up. One device that uses a heat exchanger is shown in Figure 15 (44). The Si—Al ratio in the zeolite is important, and by lowering the alumina content, the zeolite is rendered more hydrophobic and more able to adsorb... 

Sannuti, P. and Cruz, J. B., "A Note on Trajectory Sensitivity of Optimal Control Systems," IEEE Trans. Auto. Cont., 1968, AC-13, 111. 

The last step in maximum sound control is to modify the semi auto gas system by adding a gas cutoff valve. The valve is similar to the one used on the M-14. 308 rifle. When the valve is closed,the action functions in the normal semi auto mode. When open,the gas is diverted from the piston/operating rod, and the action ranains locked until opened by hand.This modification has a two fold advantage for sniping type operations. Sound is prevented from exiting the open chamber and the expended brass may be removed and pocketed, not left at the "scene". 

A Waters Associates ALC/GPC-244 instrument with M6000A solvent delivery systems, M720 system controller, 710B WISP auto-injection system, M440 UV detector, and M730 data module was used for the HPLC analyses. The following conditions were used for reverse phase HPLC ... 

Distribiiive control system with auto-sequential startup and shutdown feature, including data logging, graphing process variables, and printing periodic production reports. 

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