Improving the Analysis of Students\u27 Participation & Collaboration in Moodle Forums

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The effect of additions of anticorrosive pigments on the cathodic delamitation and wear resistance of an epoxy powder coating

The cathodic delamination and wear resistance of epoxy powder coatings were evaluated after adding 3 % (by wt.) of calcium ion exchanged micropigments from amorphous synthetic silica. The materials were manufactured through the innovative and economical hot mixing method, and three different coatings were considered: commercial epoxy, epoxy without micropigments submitted to the hot mixing treatment, and epoxy with micropigments. The curing kinetics of the powder coatings was studied in order to evaluate the possible effects of the micropigments on the epoxy, using differential scanning calorimetry (DSC). In addition, mechanical properties of coatings (hardness and scratch resistance) and their wear resistance (reciprocal tribometer tests) were assessed. After provoking a controlled mechanical failure in the coatings, their delamination resistance was analyzed by scanning Kelvin probe (SKP). The delamination front was calculated after adding a drop of 3.5 % NaCl solution and taking measurements for 26 days. The results show that the corrosion attack progresses through a cathodic delamination mechanism. The addition of corrosion inhibitors in epoxy powder coatings has not only allowed a considerable improvement in delamination resistance, but has also led to greater mechanical and wear resistance. At the same time, it has simultaneously reduced the chances for mechanical failure of the coating and decreased the progression rate of damage, if it occurs. The study has also been completed with electrochemical impedance spectroscopy and polarization measured of fully-immersed defective coatings in 3.5 % NaCl.The authors acknowledge financial support from the European Union's Horizon 2020 research and innovation program through grant agreement No 766437 (ESSIAL project)

A comparative study on the analysis of students interactions in e-learning.

Can e-learning systems effectively provide useful information to help teachers prevent students dropping out and failing as well as other access patterns useful to improve the pace of teaching? We present the data resulting from the analysis of a series of university courses in two different universities, one in Madrid, Spain, and the other one in London, United Kingdom. In order to do so, we have collected data from October 2006 to July 2007 from 400 students from 6 different courses interacting one way or the other with their e-learning platform. Thus, in these two countries a different e-learning tracking system was used to obtain the information about access; in the first one, an Ad-hoc Tracking System called Merlin placed in an in house e-learning system, and in the second one, the??standard Blackboard tracking system was used

Recursion Removal as an Instructional Method to Enhance the Understanding of Recursion Tracing

Recursion is one of the most difficult programming topics for students. In this paper, an instructional method is proposed to enhance students' understanding of recursion tracing. The proposal is based on the use of rules to translate linear recursion algorithms into equivalent, iterative ones. The paper has two main contributions: the instructional method itself, and its evaluation, which is based on previous works of other authors on mental models of recursion. As a result, an enhancement was measured in the viability of mental models exhibited by students (both for linear and multiple recursion), but no significant improvement was detected in their skills for designing recursive algorithms. Evidence was also obtained of the fact that many students with (relatively) viable mental models for linear recursion have unviable mental models for multiple recursion. Finally, it was noticed that many students adopt inaccurate mental models if those models are adequate to handle the given algorithm

A comparative study on the analysis of students interactions in e-learning.

Can e-learning systems effectively provide useful information to help teachers prevent students dropping out and failing as well as other access patterns useful to improve the pace of teaching? We present the data resulting from the analysis of a series of university courses in two different universities, one in Madrid, Spain, and the other one in London, United Kingdom. In order to do so, we have collected data from October 2006 to July 2007 from 400 students from 6 different courses interacting one way or the other with their e-learning platform. Thus, in these two countries a different e-learning tracking system was used to obtain the information about access; in the first one, an Ad-hoc Tracking System called Merlin placed in an in house e-learning system, and in the second one, the??standard Blackboard tracking system was used