This paper reports on our ongoing research around learning analytics. We focus on how learning analytics can be used to increase student motivation and the use of badges as a way to aggregate learning activity being a representation of their goals and progress along the course. The context of this work is an open learning environment, based on wikis, blogs, twitter, an activity stream mash-up a...

Through the lens of Expectancy Value Theory, we examine the effect of help giver badges, information about helper expertise, and upand downvoting on help seeking in a MOOC discussion forum. Results show that badges alleviated the negative impact on help seeking introduced by upand downvoting.

Polymer gel dosimetry undertaken on a multislice CT scanner provides an alternative method to conventional dosimetry measurements. Polymer gel dosimeters were used to measure CT radiation doses and compared to TLD and ionization chamber measurements in different diameter phantoms. CTDI was investigated for each of these phantoms for a range of mAs (100-400 mAs), tube voltage (100-135 kV) and no...

The early history of the esoteric phenomenon of thymineless death (TLD) is recounted, from the pioneering discovery by Seymour Cohen and Hazel Barner, through my graduate studies at Yale and postdoctoral research in Copenhagen. My principal contribution was the discovery that restricted synthesis of protein and RNA permits cultures of Escherichia coli to complete their DNA replication cycles wi...

The possibility to combine the track-etched CR-39 or Makrofol detectors with charcoal to increase the detector sensitivity was shown in the last years. Special requests are necessary in the case of a personal dosimeter when the detector must be active only during working activity. Regarding the combination of charcoal with TL detectors our preliminary investigations indicate that the TLD intens...

PURPOSE Thermoluminescent dosimeters are used routinely for dosimetric measurements of photon and electron fields. However, no work has been published characterizing TLDs for use in combined photon and electron fields. This work investigates the response of TLD-100 (LiF:Mg,Ti) in mixed fields of photon and electron beam qualities. METHODS TLDs were irradiated in a 6 MV photon beam, 6 MeV elec...

TLD is a tank filled with water and serves as a dynamic vibration absorber for passive control of structures. This paper addresses the comparisons of TLD performances corresponding to different tank geometries including rectangular and conical shapes. Due to the importance of water and tank weight as a load on top of a building, volume is considered to be a constant parameter in this study. Fir...

Many websites rely on user-generated content to provide value to consumers. Often these websites incentivize user-generated content by awarding users badges based on their contributions. These badges confer value upon users as a symbol of social status. In this paper, we study the optimal design of a system of badges for a designer whose goal is to maximize contributions. We assume users have h...