Automatic devices, definition

Pressure Relief Valves Definitions for pressure relief valves, relief valves, pilot-operated pressure relief valves and safety v alves, are found in the ASVIE Boiler and Pressure Assel Code, Section Division 1, Rules for Construction of Pressure Assels, Paragraphs UC-125 and UC-126, The pressure-relief valve is an automatic pressure relieving device designed to open when normal conditions are exceeded and to close again when normal conditions are restored. Within this class there are relief valves, pilot operated pressure relief valves, and safety valves. 

In this definition, the key words are documentation, specific process, product specifications, and quality. This automatically means that validation will play a vital role in guaranteeing the safety, identity, quality, and stability of all pharmaceutical, biological, and medical device products. We will now present an outline of the most important requirements for ensuring that packaging line equipment complies with the guidelines of the authorities. 

Definition 1 An automatic pressure-relieving device actuated by the static pressure upstream of the valve and characterized by a RAPID FULL OPENING or POP action. It is used for steam, gas or vapour service. 

This idea was embodied in the IUPAC definition of automatic systems "The use of combinations of mechanical and instrumental devices to replace, refine, extend, or supplement human effort and faculties in the performance of a given process, in which at least one major operation is controlled, without human intervention, by a feedback system"[367]. The key point for an automatic system is therefore the incorporation of a feedback system, i.e. the "combination of a sensing and a commanding device that can modify the performance of a given act" [367[. In other words, the response of a sensing device is used for the real-time modification of system operation. These definitions also hold for flow analysis automatic analysers are expert flow systems (Fig. 8.26), often referred to as smart or intelligent flow systems. 

Another product is a fairly popular off-line switcher IC family meant for Flyback applications. In an off-line case, the value of Dmax has several more implications. Here we must recall that the earlier generation of this switcher family had a maximum duty cycle of about 67%. When the next generation was conceived, the one-man product-definition team heuristically assigned a Dmax of 78%. His idea was that by allowing a wider input current pulse, we would automatically get a lower current pedestal, and this would enhance the power capability of his device (since this figure was being based purely on current limit, not on dissipation). 

The automatic column heads are based on a time cycle by electronic or mechanical means (c/. section 8.4) the device is alternately switched for a definite period into each of two positions the periods in question determine the reflux ratio. This requires... 

The schematic representation of the self-designed experimental set-up applied for automatic and online measurement of dielectric properties of well conducting liquids in a definite temperature range is shown in Figure 1. It is composed of the following devices and instruments cylindrical sample holder unit, thermostat, peristaltic pump, waveguide, temperature sensor, displaceable piston, stepper motor, magnetron, detectors, control unit, and a PC. 

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