Optical-Fiber Pyrometers:
Optical-fıber pyrometers are one of the most successful optical-Eber sensors in the field of process control in manufacturing. Typical applications are:
-Casting and rolling lines in steeland other metal plans
-Electric welding and annealing
-Furnaces in chemical and metal plants
-Fusion, epitaxial growth, and sputtering processs in the semiconductor industry
-Food processing, paper manufacturing, and plastic processing
Soloman S., Sensors and Control Systems in Manufacturing, p.336
Confocal Microscopy Sensors:
Confocal Microscopy inspection equipment is currently used to inspect probe marks, which is dsigned to handle high throughput, while cap-turing process excursions with high probability. Once excursions are detected, the data provides probe marks in the anomalous areas. Efficient defect revievm characterization, and mot-cause analysis require a flexible and interactive tool that can provide both lateral and height measurements, that can revisit and fully describe featurs in the areas of interest, and that can provide engineers and scientists with timely data so they can correct the problems. 'l'he tool should supply the data required for production meetings as well as images that will represent the data to management and remote customers. The tool should allow automated review and give engineers the option of full manual control to devise an effective solution.
Soloman S., Sensors and Control Systems in Manufacturing, p.110
Pilot-Operated Valves:
Process pilot-operated safely relief valves were first develoved for nudear applications; this means the basic reliability of the valves is assured. Valves for gases and vapours were developed first, the liquid valves followed later. Pilot-operated safety valves have more in common with cage-trim control valves, than wlth conventional spring operated relief valves. The pilot-operated valve consists of two assemblies: the main valve and the pilot valve. The main valve is the safety valve, which is piped into the process pipework, and the pilot valve is effectively an actuator. Pilot operated valves are suitable for liquids and gases/vapours; variations of pilot valve design are fitted to suit fluid and operating conditions.
Nesbitt B., Handbook of Valves and Actuators, p.185
Program Evaluation and Review Technique (PERT):
Gantt and milestone charts are basic scheduling tools, exceeded in their basic versions only in simplicity by a to-do Iist. A more complicated method of scheduling actvities and events uses a network model. The model depicts all the interrelated events that must take place for a proiect to be completed. The most widely used network-modeling tool is thc program evaluation and review technique (PERT). It is used to track the planning activities required to complete a large-scale, nonrepetitive project. PERT was originally developed in 1958 by the United States Department of Defense to assist with the Polaris mobile submarine launch project. PERT has the potential to reduce the time and cost required to complete a project because activities can be sequenced efficiently. A scheduling technique such as PERT is useful when certain tasks have to be completed before others if the total project is to be completed on time. ln the small office building example, the site of the building must be specified before the owner can apply for a building permit. (The building commission will grant a permit only after approving a specific location.) The PERT diagram indicates such a necessary sequence of events. PERT is used most often in engineering and construction projects. lt has also been applied to such business problems as marketing campaigns, company relocations, and convention planning. Here we examine the basics of PERT, along with a few advanced considerations.
DuBrin A.J., Essentials of Management, p.197
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