Input trimming

The process provides fast mol ding cycles, unHmited shelf life for the sheet, large part capabQity, and design flexibOity. The process also allows for scrap materials to be recycled. Trim waste from the mol ding operation and defective parts can be ground up and recycled into the basic sheet process in controUed amounts. Some of this waste has also been used as input for injection mol ding. 

Hence, a theoretical reject pressure can be calculated from pressures measured in the field, together with a constant input from a ratio-cootrol unit. The theoretical pressure proportional to the reject flow rate is then used as the set point in the control loop. The measured variable pn, in the field can then be adjusted automatically by trimming a pressure-control valve in the reject line until the calculated pn) equals the measured pnj. 

Computer Controller. The computer controller takes inputs of speed, load, and temperature to assist the engine in cold starting and to select the optimal air/fuel trim adjustment for optimal power, fuel economy, and emissions control. The control system uses the sensor signal as a switching device using the logic "rich go lean " or "lean go rich " Sophisticated adjustment logic is incorporated into the control unit to correct the air/fuel mixture... 

String record = input.substring(0, endOfRecord) samples.add(buildRecord(index + +, record)) input = n + input.substring(endOfRecord).trim() ... 

Aluminum Beverage cans Deep drawing Textured input material can lead to nonuniform wall thickness in the drawn can, and ears or variations in height that must be trimmed... 

State each function as "X does this to Y" (or Input does this to Output) Is function desired, undesired or Is function Trimming Questions (to simplify the system or reduce cost) ... 

The variables indicated by an asterisk ( ) were assigned a priori. The feedforward (FF) trim controller gain is dimensionless as both the input and the output are ratios of flows. The CSTR controller gains are in m /h reagent per m /h acid at maximum flow per pH. Some of the tuning parameters were on bounds, but the associated Lagrange multipliers did not indicate a significant incentive to rerun the optimization. 

Two linear-trim control valves are used. Valve 1 in the bypass line is AO, and valve 2 in the heat exchanger line is AC. Both valves get their inputs Ifom the CO signal from a temperature controller. 

With polymer products, most processes generate more than one marketable product. In-plant trimmings, runners, and off-specification products can be used as input to other product systems. To avoid an overwhelmingly large product system, most practitioners propose that the process tree be cut at the input of the recycled material. Those processes that are excluded must nevertheless be clearly described so as to preserve transparency. 

A control system able to react to these load variations when they occur rather than wait for them to pass through the process before initiating a corrective action would be ideal. The technique is called feedforward control. There are two types of load signals are inputs to the feedforward control system where they compute the set point of the manipulated variable control loop as a function of the measured load variations. The unmeasured load variables pass through the process, undetected by the feedforward system, and cause an upset in the controlled variable. The output of the feedback loop then trims the calculated value of the set point to the correct operating level. In the limit, feedforward control would be capable of perfect control if all load variables could be... 

D/A converter ICs often include special features that enable them to be interfaced easily to microprocessors or other systems. Microprocessor control inputs, input latches, buffers, input registers, and compatibility to standard logic families are features that are readily available in D/A ICs. In addition, the ICs usually have laser-trimmed precision resistors to eliminate the need for user trimming to achieve... 

Both instrumentation and operational amplifiers are available as single-package devices. These incorporate laser-trimmed resistors that are critically matched for optimum performance. Fixed and adjustable gain units are offered with gains up to 1000 (60 dB), equivalent input noise of —128 dB, and total harmonic distortion (THD) of 0.0001% at 20 kHz. 

Boiler trimming methodology varies by boiler manufacturer, fuel type, and control scheme regulating injected air, fuel, or both. However, in any scheme, it is critical, for safety and efficiency, to know the amount of oxygen in the process. This optimization is normally based on overall excess oxygen estimation maintaining an adequate local stoichiometry for each burner, adjustment of the flame type (based on an appropriate control of the air inputs and the operation of the mills), and identification of the optimum number of active burners for each operating load. 

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