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Metal Machining Episode 11

Tham khảo tài liệu 'metal machining episode 11', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | Optimization of machining conditions 293 Regarding the objective function in equation 9.32c as one of the constraints for fuzzy optimization optimal conditions are found from the value of the variable x V f d that maximizes the membership N ms x L m gi x 9.32d i 0 An example of fuzzy optimization of tool and cutting conditions will be presented in Section 9.3.4. 9.3.3 Knowledge-based expert systems for tool selection The previous two sections assume that there is a feasible space in which optimization can be implemented. It is in the interests of cutting tool manufacturers to make sure that that is so by designing tool holders and inserts - which give chip control stability low wear at high speeds and so on - that are not too constraining on process operation. As there are many constraints on the boundaries of feasible space and usually it is not initially clear which are critical tool selection currently relies more on the skills of machinists than does the choice of subsequent operation conditions. Tool selection systems mirror this in relying strongly on knowledge-based engineering. In addition if no tool can be selected that is a matter for process research and development rather than for process optimization. A number of different reasoning systems have developed in the field of knowledgebased engineering - names such as production blackboard semantic network frame object and predicate calculus are used to describe them Barr and Feigenbaum 1981 1982 . Tool selection systems to be described in this section are if a condition is met - then take an action rule-based or production expert systems. They all have three essential elements a workpiece description file or working memory to hold a description of a required shape change to be machined a set of rules relating machining operations and conditions to tool selection a rule base or file or production memory and a way of selecting interpreting and acting upon the rules an inference engine or interpreter . They .