Power load identification

The number and power of loads that pollute the electric network, from an electric point of view, are constantly increasing. For this reason this study aims to define a parameter to assess, in terms of distortion and unbalance, the quality of an electric network. Taking as a starting point the advantages and limitations of wavelet methods proposed in the literature, a new index useful to quantify the load characteristics is introduced. The efficiency of this index has been verified by computer simulations to assess the applicability of the method to three-phase systems using three-wire measurements based on the instantaneous power theory, in several typical situations.     

To stay or not to stay: retention of Asian international faculty in STEM fields

The present study identifies characteristics of individuals and work settings that influence Asian international faculty members’ intentions to continue their employment in US research universities. Given the demand for researchers in science, technology, engineering and mathematics fields (STEM), the higher rate of turnover among untenured faculty, and the replacement costs associated with turnover in STEM, the sample is limited to assistant professors employed in these areas. Multinomial regression analyses are conducted to identify variables that “pull” and “push” uncertain faculty toward intentions stay and leave their current institutions. The results suggest that faculty who are more satisfied with time available for research and those who express stronger organizational commitment are more likely to say they will stay. Those dissatisfied with the fairness of work evaluations and believe tenure decisions are not merit-based, are more likely to say they will leave.     

PART V: PSYCHOLOGY

Vividness and controllability of relaxing and energizing imagery by efficient and less efficient imagers.     

Building personalised homework from a learning analytics based formative assessment: Effect on fifth-grade students' understanding of fractions

This study analyses the potential of a learning analytics (LA) based formative assessment to construct personalised teaching sequences in Mathematics for 5th-grade primary school students. A total of 127 students from Spanish public schools participated in the study. The quasi-experimental study was conducted over the course of six sessions, in which both control and experimental groups participated in a teaching sequence based on mathematical problems. In each session, both groups used audience response systems to record their responses to mathematical tasks about fractions. After each session, students from the control group were given generic homework on fractions—the same activities for all the participants—while students from the experimental group were given a personalised set of activities. The provision of personalised homework was based on the students' errors detected from the use of the LA-based formative assessment. After the intervention, the results indicate a higher student level of understanding of the concept of fractions in the experimental group compared to the control group. Related to motivational dimensions, results indicated that instruction using audience response systems has a positive effect compared to regular mathematics classes.

Practitioner notes

What is already known about this topic

• Developing an understanding of fractions is one of the most challenging concepts in elementary mathematics and a solid predictor of future achievements in mathematics.
• Learning analytics (LA) has the potential to provide quality, functional data for assessing and supporting learners' difficulties.
• Audience response systems (ARS) are one of the most practical ways to collect data for LA in classroom environments.
• There is a scarcity of field research implementations on LA mediated by ARS in real contexts of elementary school classrooms.

What this paper adds

• Empirical evidence about how LA-based formative assessments can enable personalised homework to support student understanding of fractions.
• Personalised homework based on an LA-based formative assessment improves the students' comprehension of fractions.
• Using ARS for the teaching of fractions has a positive effect in terms of student motivation.

Implications for practice and/or policy

• Teachers should be given LA/ARS tools that allow them to quickly provide students with personalised mathematical instruction.
• Researchers should continue exploring these potentially beneficial educational implementations in other areas.