Month: September 2012

Koldinghus Augmented: Memories of the Walls and The Castle Chapel – Jakob Madsen, Claus Madsen

Date: 14 November 2012
Time: 13.00-14.00
Place: NJ14 3-228 (Las Vegas)

Since June 2011 we have participated in two Computer Graphics oriented projects centered around dissemination of historical knowledge with a focus on the Koldinghus Castle, in Kolding, Denmark. Koldinghus has played a major role as a part time residence for a row of kings from circa 1200 to 1700. In 1808 the castle was destroyed in a fire. The castle is now partly restored and houses a museum.

We will present two different projects: 1) an iPad based Augmented Reality game for children, and 2) a Virtual Reality visual reconstruction of the castle chapel as it appeared in early 1600 during King Christian IV’s reign.

Memories of the Walls is an interactive Augmented Reality game where children use an iPad handed out by the museum to go through an interactive narrative and solve puzzles at various stations scattered throughout the castle. In a longitudinal study we have datamined logging data from the iPads allowing us a look into what the children actually do while playing the game. The experiences from a 3 month trial period are not entirely positive, and we discuss things we have learnt from the project.

The Castle Chapel is a visual reconstruction of how the castle’s church looked like 400 years ago. We have modeled the chapel based on all available historical material, as well as on 3D scannings of surviving lime stone carvings, etc. The visual reconstruction is displayed to visitors on a pair of “view finder” stands, allowing users to look around inside the church.

MEL: A Geometric Language for Representing Musical Structure – David Meredith

CANCELED, will be presented next semester

Date: 7 November 2012
Time: 13.00-14.00
Place: NJ14 3-228 (Las Vegas)

The work described here takes its starting point in the idea that the best ways of understanding a particular musical object are those that are represented by the shortest possible descriptions of that object. I also propose that the goals of both music analysis and music perception are to find the shortest possible descriptions of musical objects. Note that a musical “object” could be a short musical fragment, a song, a multi-movement work or even a whole corpus of pieces. The goal of the research presented in this talk is to design an encoding language capable of expressing parsimonious descriptions of musical objects. This language must be able to express the types of equivalence relations that occur between musical structures, since a description of an object can often be shortened (i.e., compressed) by taking advantage of such equivalences that exist between parts of the object. The most important type of equivalence in music is translational equivalence within pitch-time space. However, musical translation is different from Euclidean geometric translation because pitch-time space can be transformed by pitch alphabets (periodic subsets of the pitch dimension) and rhythms (periodic subsets of the time dimension). Common examples of pitch alphabets are the usual scales and chords used in tonal music. Both pitch alphabets and rhythms can be represented by periodic masks, organised into mask sequences. Examples will be given of parsimonious descriptions (encodings) of musical objects that employ masks and mask sequences and an algorithm will be introduced that attempts to find such encodings from in extenso descriptions of musical objects.

Noise localization in a car – Sidsel Marie Nørholm

Date: 17 October 2012
Time: 13.00-14.00
Place: NJ14 3-228 (Las Vegas)

The localization of noise is of interest in the car industry where a good mapping will make it much easier to find the sources generating the noise and thereby lower their output. The normal methods used are the delay-and-sum beam-forming and spherical harmonics beam-forming. These methods give a bad low frequency resolution and since much noise generated in a car is of low frequency these methods are not optimal. Here the mapping is done by solving an inverse problem with a transfer matrix between the volume velocity of the sources and the measured pressures at the microphone array. The problem is very ill-posed and therefore regularization have to be applied when the transfer matrix is inverted in order to give good results.

Bio
Sidsel Marie Nørholm got a Master Degree in Sound and Acoustic Technology at the Technical University of Denmark in August 2012. In September 2012 she started as a PhD student at ad:mt  working at the project Spatio-Temporal Filtering Methods for Enhancement and Separation of Speech Signals.

Modeling Vibrotactile Detection by Logistic Regression – Lars Knudsen

Date: 03 October 2012
Time: 13.00-14.00
Place: NJ14 3-228 (Las Vegas)

In this study we introduce logistic regression as a method for modeling, in this case the user’s detection rate, to more easily show cross-effecting factors, necessary in order to design an adaptive system. Previously such effects have been investigated by a variety of linear regression type methods but these are not well suited for developing adaptive systems. We investigate the method on a qualitative and quantitative dataset with ages spanning from seven to 79 years under indoor and outdoor experimental settings. The results show that the method is indeed a suitable candidate for quantification of, in this instance vibrotactile information, and for the future design of user adaptive vibrotactile displays. More generally the model shows potential for designing a variety of adaptive systems.

Bio
Lars Knudsen finished his studies at medialogy the summer 2011 where his master thesis concerned tactile displays and navigation, supervised by Hans Jørgen Andersen and Ann Morrison. Afterwards he has continued studying the field of tactile displays, especially with a focus on modeling modeling vibrotactile sensitivities.