Since my last few posts were all about OSS Notes, I want to share one more thing before I move to a new subject, but this time it is a COPY and PASTE from SAP OSS. Automate eBay searches with SearchDome's eBay search tools. Create searches that run once a day. System Help SAP Automated Note Search and Customer Code Detection Tool Tables o Application Component (8C)-8asis Components-(256) Conwonents-(13). Use the search and download tool to find out if a Foreign Financial Institution has registered with FATCA. Electronic Federal Tax Payment System. Examiner Automated Search ToolAcronym Definition; EAST: Eastern Association for the Surgery of Trauma: EAST: Examiner Automated Search Tool (US Patent and Trademark Office) EAST: Environmental and. Search eBay Automatically With AutomatedSearches.com. Special Misspelled Auctions search feature; Save hours with our Automated Seller Question System. Test Studio Automated Testing Made Easy. The complete test automation solution for GUI, Performance. Amtomated Shipment Inspection Status Search Tool. Canadian Food Inspection Agency www.inspection.gc.ca. 902 Search Tools and Classification Information . Automated Search Tools: EAST and WEST SAP ONE Support Launchpad - Whishlist part 2 -> notes search app / ANST Automation - Wikipedia. Automation. Some processes have been completely automated. In modern days, it is also used in our homes. Smart home system is one of the every day application . Complicated systems, such as modern factories, airplanes and ships typically use all these combined techniques. Open- loop and closed- loop (feedback) control. A good example of this is a central heating boiler controlled only by a timer, so that heat is applied for a constant time, regardless of the temperature of the building. The process output is the building temperature). In closed loop control, the control action from the controller is dependent on the process output. In the case of the boiler analogy this would include a thermostat to monitor the building temperature, and thereby feed back a signal to ensure the controller maintains the building at the temperature set on the thermostat. A closed loop controller therefore has a feedback loop which ensures the controller exerts a control action to give a process output the same as the . For this reason, closed loop controllers are also called feedback controllers. An example is the thermostat used on household appliances which either opens or closes an electrical contact. An elevator control system is an example of sequence control. PID controller. An example of an adjustable but otherwise fixed sequence is a timer on a lawn sprinkler. State Abstraction. This state diagram shows how UML can be used for designing a door system that can only be opened and closed. States refer to the various conditions that can occur in a use or sequence scenario of the system. An example is an elevator, which uses logic based on the system state to perform certain actions in response to its state and operator input. For example, if the operator presses the floor n button, the system will respond depending on whether the elevator is stopped or moving, going up or down, or if the door is open or closed, and other conditions. Relays were first used in telegraph networks before being developed for controlling other devices, such as when starting and stopping industrial- sized electric motors or opening and closing solenoid valves. Using relays for control purposes allowed event- driven control, where actions could be triggered out of sequence, in response to external events. These were more flexible in their response than the rigid single- sequence cam timers. More complicated examples involved maintaining safe sequences for devices such as swing bridge controls, where a lock bolt needed to be disengaged before the bridge could be moved, and the lock bolt could not be released until the safety gates had already been closed. The total number of relays, cam timers and drum sequencers can number into the hundreds or even thousands in some factories. Early programming techniques and languages were needed to make such systems manageable, one of the first being ladder logic, where diagrams of the interconnected relays resembled the rungs of a ladder. Special computers called programmable logic controllers were later designed to replace these collections of hardware with a single, more easily re- programmed unit. In a typical hard wired motor start and stop circuit (called a control circuit) a motor is started by pushing a . Large motors use high voltage and experience high in- rush current, making speed important in making and breaking contact. This can be dangerous for personnel and property with manual switches. Suppose that the motor in the example is powering machinery that has a critical need for lubrication. In this case an interlock could be added to insure that the oil pump is running before the motor starts. Timers, limit switches and electric eyes are other common elements in control circuits. Solenoid valves are widely used on compressed air or hydraulic fluid for powering actuators on mechanical components. While motors are used to supply continuous rotary motion, actuators are typically a better choice for intermittently creating a limited range of movement for a mechanical component, such as moving various mechanical arms, opening or closing valves, raising heavy press rolls, applying pressure to presses. Computer control. Programmable logic controllers (PLCs) are a type of special purpose microprocessor that replaced many hardware components such as timers and drum sequencers used in relay logic type systems. General purpose process control computers have increasingly replaced stand alone controllers, with a single computer able to perform the operations of hundreds of controllers. Process control computers can process data from a network of PLCs, instruments and controllers in order to implement typical (such as PID) control of many individual variables or, in some cases, to implement complex control algorithms using multiple inputs and mathematical manipulations. They can also analyze data and create real time graphical displays for operators and run reports for operators, engineers and management. Control of an automated teller machine (ATM) is an example of an interactive process in which a computer will perform a logic derived response to a user selection based on information retrieved from a networked database. The ATM process has similarities with other online transaction processes. The different logical responses are called scenarios. Such processes are typically designed with the aid of use cases and flowcharts, which guide the writing of the software code. History. It was patented by Edmund Lee in 1. The governor was able to handle smaller variations such as those caused by fluctuating heat load to the boiler. Also, there was a tendency for oscillation whenever there was a speed change. As a consequence, engines equipped with this governor were not suitable for operations requiring constant speed, such as cotton spinning. Advances in the steam engine stayed well ahead of science, both thermodynamics and control theory. Development of the electronic amplifier during the 1. This and other telephony applications contributed to control theory. Military applications during the Second World War that contributed to and benefited from control theory were fire- control systems and aircraft controls. Central electric power stations were also undergoing rapid growth and operation of new high pressure boilers, steam turbines and electrical substations created a large demand for instruments and controls. Central control rooms became common in the 1. Operators typically monitored charts drawn by recorders that plotted data from instruments. To make corrections, operators manually opened or closed valves or turned switches on or off. Control rooms also used color coded lights to send signals to workers in the plant to manually make certain changes. Controllers allowed manufacturing to continue showing productivity gains to offset the declining influence of factory electrification. Manufacturing productivity growth fell from 5. Field notes that spending on non- medical instruments increased significantly from 1. Automatic telephone switching originally used vacuum tube amplifiers and electro- mechanical switches, which consumed a large amount of electricity. Call volume eventually grew so fast that it was feared the telephone system would consume all electricity production, prompting Bell Labs to begin research on the transistor. The cost of making bottles by machine was 1. Sectional electric drives were developed using control theory. Sectional electric drives are used on different sections of a machine where a precise differential must be maintained between the sections. In steel rolling, the metal elongates as it passes through pairs of rollers, which must run at successively faster speeds. In paper making the paper sheet shrinks as it passes around steam heated drying arranged in groups, which must run at successively slower speeds. The first application of a sectional electric drive was on a paper machine in 1. In 1. 93. 0, with the widespread use of instruments and the emerging use of controllers, the founder of Dow Chemical Co. This soon evolved into computerized numerical control (CNC). Today extensive automation is practiced in practically every type of manufacturing and assembly process. Some of the larger processes include electrical power generation, oil refining, chemicals, steel mills, plastics, cement plants, fertilizer plants, pulp and paper mills, automobile and truck assembly, aircraft production, glass manufacturing, natural gas separation plants, food and beverage processing, canning and bottling and manufacture of various kinds of parts. Robots are especially useful in hazardous applications like automobile spray painting. Robots are also used to assemble electronic circuit boards. Automotive welding is done with robots and automatic welders are used in applications like pipelines. Advantages and disadvantages. In order to eliminate the need for labor costs altogether. Health and environment. There are automated engines that consume more energy resources from the Earth in comparison with previous engines and those that do the opposite. Manufacturers are increasingly demanding the ability to easily switch from manufacturing Product A to manufacturing Product B without having to completely rebuild the production lines. Flexibility and distributed processes have led to the introduction of Automated Guided Vehicles with Natural Features Navigation. Digital electronics helped too. Former analogue- based instrumentation was replaced by digital equivalents which can be more accurate and flexible, and offer greater scope for more sophisticated configuration, parametrization and operation. This was accompanied by the fieldbus revolution which provided a networked (i. The more conservative process industries with their longer plant life cycles have been slower to adopt and analogue- based measurement and control still dominates.
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