Enhancing the Digital Backchannel Backstage on the Basis of a Formative User Study

Contemporary higher education with its large audiences suffers from passivity of students. Enhancing the classroom with a digital backchannel can contribute to establishing and fostering active participation of and collaboration among students in the lecture. Therefore, we conceived the digital backchannel Backstage specifically tailored for the use in large classes. At an early phase of development we tested its core functionalities in a small-scale user study. The aim of the study was to gain first impressions of its adoption, and also to form a basis for further steps in the conception of Backstage. Regarding adoption we particularly focused on how Backstage influences the participants' questioning behavior, a salient aspect in learning. We observed that during the study much more questions were uttered on Backstage than being asked without backchannel support. Regarding the further development of Backstage we capitalized on the participants' usability feedback. The key of the refinement is the integration of presentation slides in Backstage, which leads to an interesting reconsideration of the user interactions of Backstage

Providing guidance on Backstage, a novel digital backchannel for large class teaching

Many articles in the last couple of years argued that it is necessary to promote the active participation of students in lectures with large audiences. One approach to make students actively participate in a lecture is to use a digital backchannel, i.e. a computer-mediated communication platform that allows students to exchange ideas and opinions, without disrupting the lecturer’s discourse. Though, a digital backchannel, in order to be most helpful for learning, have to address the need for guidance of the users interacting. The article presents Backstage, a digital backchannel for large class lectures, and shows how it provides guidance for its users, i.e. the students but also the lecturer. Structural guidance is provided by aligning the usually incoherent backchannel discourse with the presentation slides that are integrated in the backchannel’s user interface. The alignment is thereby asserted by carefully designed backchannel workflows. The article also discusses the guidance of a student’s substantial involvement in both the frontchannel and the backchannel by means of scripts. Through the interactions of guided individuals a social guidance may emerge, leading to a collectively regulated backchannel

Combining Higher Order Reflections with Diffractions without Explosion of Computation Time: The Sound Particle Radiosity Method

The simulation of sound propagation in large rooms and urban environments is mainly performed by geometric simulation methods like ray tracing or the Sound Particle Simulation Method (SPSM). Hence, a severe deficiency is that wave effects are not included, especially if screening or diffraction effects are important. A method to introduce diffraction is the Uncertainty relation Based Diffraction (UBD) model, which has been successfully evaluated recently. To find close edges as sources of diffraction, a subdivision of the room into convex subspaces is performed by virtual walls. However, this causes a recursive split-up of Sound Particles (SPs) at each diffraction event. This effect should be compensated by a reunification of SPs. Therefore, the Sound Particle Radiosity (SPR) has been found that combines the SPSM with an advantage of the radiosity method: the re-unification of sound energy that uses a discretization of the surface into small patches. Now, SPR has been extended to 3D for the first time. To increase the available memory and to decrease the computation time, a parallelization has been implemented for the first time. First results indicate that the discretization of the virtual walls into patches yields additional but tolerable errors in the simulation of diffraction. However, even in 2D, SPR requires a huge memory. To solve this problem in 3D remains a great challenge, even more for more complex rooms. Also a method for a convex subdivision to 3D still has to be found

P6 7 The Perfect Cuppa: The Search for the Best Place in the Solar System to Brew a Cup of Tea

In this paper we calculate the boiling point of water in several locations around the solar systemand describe the eects on the human body of drinking water at this temperature. We are able toconclude that Titan is the only body in the solar system with an atmosphere thick enough to allowthe production of a cup of tea like those made on Earth on its surface, while the Martian surfacewould facilitate production of a beverage resembling a refrigerated drink or ice-cream. Venus couldprove useful for making a cup of tea if a oating platform could be constructed on the planet

P6 5 Evidence for a Diamond Layer in the Mantle of Neptune

This paper explores the idea of diamond formation in gas giants. We apply terrestrial experimentaldata to the theoretical atmospheric composition and structure of Neptune. We conclude that it isfeasible that a solid layer of diamond could form in the conditions on Neptune, completely replacingthe layer of liquid methane predicted on the planet. This is not in line with current theories butdoes have some supporting evidence from the scientic community, and further observational datais required

P6_3 One Hundred and Eighty!

This paper uses a computer simulation to examine how aiming for different targets on a common dartboard affects the average score for varying accuracy. As expected when accuracy is high and the spread of hits approaches a delta function, the best target is the treble twenty, and when the spread of hits is completely uniform over a circle, the best target is the centre of the board. Between these extremes however the best target moves across the board, generally toward the lower left quadrant. This could provide assistance to players who find aiming for the treble twenty is not beneficial for them due to a low accuracy, and in fact aiming for lower numbers may increase their average score