The Prediction of Students’ Track Appropriateness in School - Students’ Ethnicity as a Moderator of the Prediction’s Validity

In Luxembourg and other European countries, school placement decisions made at the end of primary school determine the track a student will follow in secondary school. About one-third of the students in Luxembourg come from immigrant families. Research has shown that this demographical factor influences school placement decisions, as students with an immigration background are more likely to be oriented towards a lower track than are native students (e.g., [1]). It seems reasonable to assume that immigration background may also moderate the predictive validity of school placement decisions. In the present study, we examined whether students’ nationality moderates the predictive validity of school placement decisions in Luxembourg. We compared school placement decisions of three age-cohorts of students with the tracks they attended three to five years later. Subgroup analyses revealed that the predictive validity of school placement decisions was actually affected by nationality. Kappa coefficients, expressing the closeness of the relationship between placement decisions and the actual track, were higher for Luxembourgish students than for students of other nationalities. Additionally, multilevel regression analysis showed that Luxembourgish students were more likely to keep on the track than immigrant students

Recursive State of Charge and State of Health Estimation Method for Lithium-Ion Batteries Based on Coulomb Counting and Open Circuit Voltage

The state of charge (SOC) and state of health (SOH) are two crucial indicators needed for a proper and safe operation of the battery. Coulomb counting is one of the most adopted and straightforward methods to calculate the SOC. Although it can be implemented for all kinds of applications, its accuracy is strongly dependent on the operation conditions. In this work, the behavior of the batteries at different current and temperature conditions is analyzed in order to adjust the charge measurement according to the battery efficiency at the specific operating conditions. The open-circuit voltage (OCV) is used to reset the SOC estimation and prevent the error accumulation. Furthermore, the SOH is estimated by evaluating the accumulated charge between two different SOC using a recursive least squares (RLS) method. The SOC and SOH estimations are verified through an extensive test in which the battery is subjected to a dynamic load profile at different temperatures