Feedback: automated processes

An automated process is a series of sequential steps to be carried out automatically. Servomechanisms are systems, devices, and subassemblies that control the mechanical actions of robots by the use of feedback information from the overall system in operation. 

Another essential component in the functioning of automated processes and servomechanisms is the feedback control systems that provide self-regulation and auto-adjustment of the overall system. Feedback control systems may be pneumatic, hydraulic, mechanical, or electrical in nature. Electrical feedback may be analogue in form, although digital electronic feedback methods provide the most versatile method of output sensing for input feedback to digital electronic control systems. 

Another important field of application for chemical sensors is process control. Here the sen- sor is expected to deliver some crucial signal to the actuators (valves, pumps, etc.) that control the actual process. Fully automated process control is feasible with certain types of feedback circuits. Since key chemical parameters in many chemical or biochemical processes are not subject to sufficiently accurate direct determination by the human senses, or even via the detour of a physical parameter, sensor technology becomes the key to automatic process and quality control. Often the performance of an entire industrial process depends on the quality and reliability of the sensors employed. Successful adaptation of a batch process to flow-through reactor production technology... 

It s stated that a complete quick scan process can be finished within a two-week period. Once this is done, a feedback presentation is conducted during which opportunities and improvements are discussed. The quick scan is therefore of importance, since it helps in fully comprehending the current state of the supply chain and in determining those actions that will yield maximum benefit which can be implemented before or with the automation process. The approach however, is not sufftciently strategic, can only be seen under operative circumstances and does not explicitly mention supply chain differentiation. 

The distinction between controlled and automated processes was first defined and studied by Schneider and Shiffrin (1977). In a series of laboratory studies they demonstrated that the process by which we learn to deal with complex situations involves the automation of various sequences of behavior. Prior to automation each component in that behavior is controlled through monitoring and feedback. This process is relatively slow, requires much attention, and prevents us from doing other tasks simultaneously. As we repeatedly perform some of these sequences, the process becomes automated, in the sense that once it is initiated, the sequence of actions is hardly monitored, requires minimal attention, and is performed more or less unconsciously. Changing manual gears has often been used as an example of a controlled process that through repeated experience becomes automated. The concepts of controlled and automated processes are discussed in more details in Chapter 5 on Information Processing. 

On-Hne Procedures The growing trend toward automation in industry has resiilted in many studies of rapid procedures for generating size information so that feedback loops can be instituted as an integral part of a process. Many of these techniques are modifications of more traditional methods. The problems associated with on-line methods include allocation and preparation of a representative sample analysis of the sample evaluation of the results. The interface between the measuring apparatus and the process has the potential of high complexity, and consequently, high costs [Leschonsld, Paiticle Cha racterization, 1, 1 (July 1984)]. 

While the decrease in extraction time is favourable for laboratories in general, it can be critical when laboratory analyses are used in feedback control of production cycles and quality control of manufacturing processes. The volume of solvents used in PFE can be some 10 times less than traditional extraction methods (cf. Table 3.36). PFE cuts solvent consumption by up to 95 %. Because so little solvent is used, final clean-up and concentration are fast direct injection in analytical devices is often possible. Automated PFE systems can extract up to 24 sample cells. 

Although some depolymerases act processively in cleaving their polymeric substrates, others act by what can be described as multiple attack which results in nonselective scission or random scission. The analysis of cleavage products during the course of enzyme-catalyzed depolymerization can provide important clues about the nature of the reaction. With random scission, the rate of bond scission must be proportional to the total number of unbroken bonds present in the solution. Thomas measured the rate of base addition in a pH-Stat (a device with an automated feedback servomotor that expels ti-trant from a syringe to maintain pH) to follow the kinetics of DNA bond scission by DNase. The number of bonds cleaved was linear with time, and this was indicative of random scission. In other cases, one may apply the template challenge method to assess the processivity of nucleic acid polymerases. See Processivity... 

Ranky, P. G. (2003), A real-time manufacturing/assembly system performance evaluation and control model with integrated sensory feedback processing and visualization, Assembly Automation. 

Laboratory robotics is not an outgrowth of classical industrial robotics (manufacturing robotics). Developed independently, it focuses on the chemical process rather than on robotic hardware development. However, much of the technology that was previously developed and tested for industrial automation has found uses in laboratory robotics. Also, some classical terms are routinely used in connection with laboratory robotics and laboratory automation. By 1994, robotics had seemingly reached maturity, so a specific nomenclature for laboratory robotics and automation was issued by lUPAC [2,3]. Some of lUPAC s recommended terms are general and require the word robot or robotics for specific use (e.g. in controlled-path robots , corrosion-resistant robots , feedback in robotics , accuracy in robotics ) others are characteristic of robotic technology (e.g. arm , articulate structure , flexible automation , manipulator ). 

Automation involves the use of systems (instruments) in which an element of nonhuman decision has been interpolated. It is dehned as the use of combinations of mechanical and instrumental devices to replace, rehne, extend, or supplement human effect 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, A feedback system is defined as an instrumental device combining sensing and commanding elements which can modify the performance of a given act [1],... 

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