10467921
Gesture Desk - An Integrated Multi-modal Gestural Workplace for Sonification
This paper presents the gesture desk, a new platform for a human-computer interface at a regular computer workplace. It extends classical input devices like keyboard and mouse by arm and hand gestures, without the need to use any inconvenient accessories like data gloves or markers. A central element is a “gesture box” containing two infrared cameras and a color camera which is positioned under a glass desk. Arm and hand motions are tracked in three dimensions. A synchronizer board has been developed to provide an active glare-free IR-illumination for robust body and hand tracking. As a first application, we demonstrate interactive real-time browsing and querying of auditory self-organizing maps (AuSOMs). An AuSOM is a combined visual and auditory presentation of high-dimensional data sets. Moving the hand above the desk surface allows to select neurons on the map and to manipulate how they contribute to data sonification. Each neuron is associated with a prototype vector in high-dimensional space, so that a set of 2D-topologically ordered feature maps is queried simultaneously. The level of detail is selected by hand altitude over the table surface, allowing to emphasize or deemphasize neurons on the map.
5682288
Guest Editors' Introduction: An Introduction to Interactive Sonification
The research field of sonification, a subset of the topic of auditory display, has developed rapidly in recent decades. It brings together interests from the areas of data mining, exploratory data analysis, human-computer interfaces, and computer music. Sonification presents information by using sound (particularly nonspeech), so that the user of an auditory display obtains a deeper understanding of the data or processes under investigation by listening.
36348317
Identification of discriminative features in the EEG
An important step for the correlation of EEG signals with cognitive processes is the identification of discriminative features in the EEG signal. In this paper we utilize independent component analysis (ICA) for feature extraction and selection. Our specific ICA technique is based on a nonparametric source representation which in particular allows for modelling of multimodal feature distributions as generally required for the analysis of mixed data from different experiment conditions. To demonstrate the potential of the resulting ICA feature selection scheme we report results from an analysis of psycholinguistic experiments on the discrimination of speech perception from perception of so-called pseudo speech signals and demonstrate how the obtained ICA features can be further analyzed with the technique of sonification. Our results correlate well with results from coherence analysis and strongly indicate that these new methods are well suited for uncovering cognitively relevant features in EEG signals.
40071496
tacTilesfor Ambient Intelligence and Interactive Sonification
In this paper we introduce tacTiles, a novel wireless modular tactile sensitive surface element attached to a deformable textile, designed as a lay-on for surfaces such as chairs, sofas, floor or other furniture. tacTilescan be used as interface for human-computer interaction or ambient information systems. We give a full account on the hardware and show applications that demonstrate real-time sonification for process monitoring and biofeedback. Finally we sketch ideas for using tacTiles paired with sonification for interaction games.
944953
The Sonification of Rhythms in Human Electroencephalogram
We use sonification of temporal information extracted from scalp EEG to characterize the dynamic properties of rhythms in certain frequency bands. Sonification proves particularly useful in the simultaneous monitoring of several EEG channels. Our results suggest sonification as an important tool in the analysis of multivariate data with subtle correlation differences.
5897687
Polyrhythmic organization of coupled nonlinear oscillators
We study the rhythmic organization of coupled nonlinear oscillators. If oscillators with non-identical internal frequency are coupled, they generate a great variety of periodic and chaotic rhythmic patterns. Sonification of these patterns suggests their characterization in terms of polyrhythms: each oscillatory unit subdivides "measures" of equal or varying length differently. For the case of two coupled oscillators, the organization of these polyrhythms is exemplified as a function of the internal frequency ratio and the coupling strength. Some sonification strategies are presented which aid to detect complex rhythmic relationships between oscillators. The results may be of importance for the analysis of complex multivariate time series like human EEG.
35470477
A new insight into the Gn continuity of polynomial surfaces
Abstract A theorem of Degen describes the structure of G 1 and G 2 connection between two polynomial surfaces. This is based on common vector polynomials and an irreducibility condition of one of these vector functions related to the common boundary. In this paper Degen's results are reformulated, a new proof and a new interpretation is given which makes it possible to generalize the previous results to G n continuity. Surprisingly, in case of G n continuity, there is no need to add further conditions than for the G 1 G 2 cases, still exists a common G n continuous polynomial virtual patch with polynomial reparametrizations.
39788442
Best Fit Surface Curvature at Vertices of Topologically Irregular Curve Networks
42414181
G2 interpolation of free form curve networks by biquintic Gregory patches
Abstract The problem of interpolating a free form curve network with irregular topology is investigated in order to create a curvature continuous surface. The spanning curve segments are parametric quintic polynomials, the interpolating surface elements are biquintic Gregory patches. A necessary compatibility condition is formulated and proved which need to be satisfied at each node of the curve network. Constraints are derived for assuring G 2 continuity between biquintic Gregory patches, which share a common side or a common corner point. The above conditions still leave certain geometric freedom for defining the entire G 2 surface, so following some analysis a particular construction is presented, by which after computing the principle curvatures at each node the free parameters are locally set for each interpolating Gregory patch.
19159245
Improving and Extending the Lim/Lee Exponentiation Algorithm
. In [5] Lim and Lee present an algorithm for fast exponentiation in a given group which is optimized for a limited amount of storage. The algorithm uses one precomputation for several computations in order to minimize the average time needed for one exponentiation. This paper generalizes the previous work proposing several improvements and a method for fast precomputation. The basic Lim/Lee algorithm is improved by determining the optimal segmentation of the exponent. Finally, it is shown that the improved Lim/Lee algorithm is faster than the previous one in average case.
15389938
Geometrical criteria on the higher order smoothness of composite surfaces
Abstract A generalization of a theorem by Pegna and Wolter—called Linkage Curve Theorem—is presented. The new theorem provides a condition for joining two surfaces with high order geometric continuity of arbitrary degree n. It will be shown that the Linkage Curve Theorem can be generalized even for the case when the common boundary curve is only G1.