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Sleep spindle activity in infants supports their formation of generalized memories during sleep, indicating that specific sleep processes affect the consolidation of memories early in life. Characteristics of sleep spindles depend on the infant's developmental state and are known to be associated with trait‐like factors such as intelligence. It is, however, largely unknown which state‐like factors affect sleep spindles in infancy. By varying infants’ wake experience in a within‐subject design, here we provide evidence for a learning‐ and memory‐dependent modulation of infant spindle activity. In a lexical‐semantic learning session before a nap, 14‐ to 16‐month‐old infants were exposed to unknown words as labels for exemplars of unknown object categories. In a memory test on the next day, generalization to novel category exemplars was tested. In a nonlearning control session preceding a nap on another day, the same infants heard known words as labels for exemplars of already known categories. Central–parietal fast sleep spindles increased after the encoding of unknown object–word pairings compared to known pairings, evidencing that an infant's spindle activity varies depending on its prior knowledge for newly encoded information. Correlations suggest that enhanced spindle activity was particularly triggered, when similar unknown pairings were not generalized immediately during encoding. The spindle increase triggered by previously not generalized object–word pairings, moreover, boosted the formation of generalized memories for these pairings. Overall, the results provide first evidence for a fine‐tuned regulation of infant sleep quality according to current consolidation requirements, which improves the infant long‐term memory for new experiences.

Multiple enterprise system instances in organizations with multiple business units are quite costly to maintain and causes the lack of common business processes. To consolidate these systems into one or fewer instances has the benefits of reduce costs, centralize IT and standardize business processes. But a consolidated model may not be the best choice for every company. To help companies with this decision making process, we studied relevant papers and provided several consideration factors that companies should concern before conducting a system consolidation program. By analyzing their situation according to these factors, companies will get a clearer view on whether they should consolidate their enterprise systems or not. In this thesis a case study is conducted with Holmen Paper. Our study with Holmen Paper focused on the maintenance area of theirs three paper mills. By analyzing these paper mills’ situations based on three of our consideration factors, we made the conclusion that Holmen Paper should consolidate their systems in the maintenance area when they are ready.