Please polish the following text "In process industries, the key to ensuring smooth operation of the production is to control the operation indices within their desired ranges. These operation indices mostly reflect the quality of the production process, such as material and energy consumption, or the quality of the product, such as material composition, grade, size distribution, etc. The goal of industrial process operation optimization control is to control the production operation index within the target range by tracking the set points of the control system under the condition of safe operation, while maximizing those operation index related to product quality and efficiency and minimizing those related to consumption. However, in actual production, it is often difficult to obtain the operating index online, so it is difficult to realize the closed-loop control of the operating indices. Therefore, the development of the predictive model of the key operation indices is vital to operation optimization control." Use words with all capital letters to highlight key points, but make sure that words with all capital letters appear less than 19 times
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