Educational robotics has proven its positive impact on the performances and attitudes of students. However, the educational environments that employ them rarely provide teachers with relevant information that can be used to make an effective monitoring of the student learning progress. To overcome these limitations, in this paper we present IDEE (Integrated Didactic Educational Environment), an educational environment for physics, that uses EV3 LEGO Mindstorms R educational kit as robotic component. To provide support to teachers, IDEE includes a dashboard that provides them with information about the students' learning process. This analysis is done by means of an Additive Factor Model (AFM). That is a well-known technique in the educational data mining research area. However, it has been usually employed to carry out analysis about students' performance data outside the system. This can be a burden for the teacher who, in most cases, is not an expert in data analysis. Our goal in this paper is to show how the coefficients of AFM provide valuable information to the teacher without requiring any deep expertise in data analysis. In addition, we show an improved version of the AFM that provides a deeper understanding about the students' learning process.

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A supercharger is a mechanical device that can be added to an engine of a car to increase engine power. It works by sucking air in at atmospheric pressure into the rotors and compressing it at high revolutions per minute. With the rotors spinning at high speeds, the supercharger gears are exposed to high values of friction and wear, which results in a reduction of their service life. Ionic liquids (ILs) are substances that possess unique lubricating abilities when added to base oil or when used as neat lubricants. Properties include low volatility, non-flammability, as well high thermal resistance. These liquids are able to form ordered layers and tribofilms on the contacting surfaces which further protects the surface materials. In this work, the effect of adding ILs to low viscosity synthetic oil used to lubricate gears and to organic oil was investigated in the reduction of friction and overall wear of superchargers. Mobil 1 5W-30 Full Synthetic Engine Oil (MS) was used as a control and compared to coffee bean oil (CB). Additionally, the performance of these oils was observed with ionic liquids as additives at 1 wt. %. The chosen IL consisted of the cation Trihexyltetradecylphosphonium, [P6,6,6,14]+, with the anion Bis(trifluoromethylsulfonyl) amide, [NTf2]−. Lubricated flat disks of AISI 52100 stainless steel and 420C steel balls were studied using a Pin-on-Disk configuration. A total sliding distance of 500 meters was tested with a wear track diameter of 20 mm. Wear volume and average friction coefficient were measured according to ASTM-G99. Results showed that the addition of the ILs to the CB and MS reduced friction coefficient of the steel disks at medium speeds, and wear values achieved were comparable to the friction observed. The wear width values were also found to be reduced at medium speeds.