Position control

The apparatus consists of a tip-position controller, an electrochemical cell with tip, substrate, counter and reference electrodes, a bipotentiostat and a data-acquisition system. The microelectrode tip is held on a piezoelectric pusher, which is mounted on an inchwomi-translator-driven x-y-z tliree-axis stage. This assembly enables the positioning of the tip electrode above the substrate by movement of the inchwomi translator or by application of a high voltage to the pusher via an amplifier. The substrate is attached to the bottom of the electrochemical cell, which is mounted on a vibration-free table [, and ]. A number... [Pg.1941]

Valve Positioners The valve positioner, when combined with an appropriate actuator, forms a complete closed-loop valve-position control system. This system makes the valve stem conform to the input signal coming from the process controller in spite of force loads that the actuator may encounter while moving the control valve. Usually, the valve positioner is contained in its own enclosure and is mounted on the control valve. [Pg.783]

Provide positive control room pressure to prevent inflow of hazardous material... [Pg.32]

Control in the wrong position Control settings do not change Control settings may be purposefully changed for different phases of batches, different batches or similar batches... [Pg.129]

NEMA/MG-7/1993 Motion/position control motors and cables ... [Pg.162]

All valves are equipped with hydraulic actuators, electronic positioning controllers for precise positioning, and solenoid valves for rapid (trip) opening of bypass valves and emergency closure tripping of trip and inlet control valves. [Pg.383]

Example 4.6.1 CNC Maehine-Tool Positional Control (See also Appendix 1, examp461.m)... [Pg.92]

Fig. 4.41 Angular positional control system. = Error detector gain (V/rad) K2 = Amplifier gain (A/V) Kj = Motor constant (Nm/A) n = Gear ratio Hi = Tachogenerator constant (Vs/rad) H = Load moment of inertia (kg m ) Q = Load damping coefficient (Nms/rad).

The block diagram for an angular positional control system is shown in Figure 10.36. The system parameters are ... [Pg.368]

The angular positional control system shown by the block diagram in Figure 10.36 is to have the velocity feedback loop removed and controller K replaced by a fuzzy logic controller (FLC) as demonstrated by Barrett (1992). The inputs to the FLC... [Pg.373]

Case study Example 4.6.1 is a CNC machine-tool positional control system, whose block diagram representation is shown in Figure 4.31. When system parameter values are inserted, the block diagram is as shown in Figure A1.2. [Pg.386]

Fig. A1.3 SIMULINK simulation of CNC machine-tool positional control system.

Grimble, M.J., Patton, R.J. and Wise, D.A. (1979) The design of dynamic ship positioning control systems using extended Kalman filtering techniques, IEEE Conference, Oceans 79, CA, San Diego. [Pg.430]

The following deamination transform, 28 => 29, illustrates how FGA can be used for positional control for a subsequent aromatic FG removal (FGR) transform, 29 => 30. [Pg.14]

On/off control A simple two-position control system that is only capable of performing these two functions (on and off). [Pg.1463]

Opwatad ValVM 3.5.3.1 Hvdraulic. 1 Fail Close Actuator. 2 Fall Open Actuator. 3 Fail in Position Actuator. 1 AMamating (2-position Control). 2 Continuous (Throttling Control). 3 Standby Open. 4 Standby Closed 1-4 All Modes Catastrophic a. External Leakage b. Internal Leakage > 1% c. Spurious Operation d. No Change of Position on Demand... [Pg.274]

Automatic water-level controls arranged to positively control the flow of water into the boiler and maintain a set level between predetermined limits ... [Pg.365]

Figure 31.2 UmWs of controlled variable with two-position control.

Four different European herbaceous plants have also been tested for possible mitogenic and comitogenic activities. Using Zymosan as a positive control, all polysaccharide fractions tested had higher activity in the bioassays... [Pg.97]

Mango fruits (Mangifera indica) were kept in carton boxes whose top surface was covered with either chitosan film or with low-density polyethylene (positive control) and stored at room temperature (27 1 °C at 65% RH). The CO2 and O2 levels measured on day 3 were 23-26% and 3-6%, and at the... [Pg.183]

Christman, M.F., Morgan,R.W., Jacobson, F.S., Ames, B. (1985). Positive control of a regulon for defenses against oxidative stress and some heat shock proteins in Salmonella typhimurium. Cell 41, 753-762. [Pg.452]

Endosulfan administered by gavage at 1.5 mg/kg/day for 30 days to ovariectomized rats did not influence the relative weights or histology of the uterus, cervix, or vagina compared to ovariectomized control rats that did not receive endosulfan (Raizada et al. 1991). Rats in a positive control group received intraperitoneal injections of estradiol and showed increased relative organ weights and normal development of female reproductive tissues compared to the untreated ovariectomized control rats. [Pg.89]

Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...