The Narrative Presentation of Orality in James Joyce's Finnegans Wake

Processing Note: Further review neededThe Milman Parry Lecture on Oral Tradition for 1990-9

24th Bilateral Student Workshop CTU Prague and HTW Dresden - User Interfaces & Visualization

This technical report publishes the proceedings of the 24th Bilateral Student Workshop CTU Prague and HTW Dresden -User Interfaces & Visualization-, which was held on the 26th November 2021. The workshop offers a possibility for young scientists to present their current research work in the fields of computer graphics, human-computer-interaction, robotics and usability. The works is meant as a platform to bring together researchers from both the Czech Technical University in Prague (CTU) and the University of Applied Sciences Dresden (HTW). The German Academic Exchange Service offers its financial support to allow student participants the bilateral exchange between Prague and Dresden.:1) Robot assisted reminiscence therapy for people with dementia, p.4 2) VENT-CONECT: System for remote monitoring of instruments used in intensive care, p.12 3) Conversational assistant for smart home, p.17 4) Perspectives and challenges of the research project ”SYNC ID” , p.23 5) Music-based emotional biofeedback: the state of the art and challenges, p.26 6) Ambient Assisted Living Lab - Smart Systems and CoCreation, p.30 7) Board Game Playing and Consuming Beverages in VR, p.36 8) An approach to measure and increase the level of participation of people with dementia in cognitive games, p.41 9) Forced perspective illusions and scaling users in VR - state of the art., p.47 10) Training Deep Learning Models for Punctuation Prediction, p.51 11) Towards an Evaluation of Ambiguity in Point-Feature Labelling, p.56 12) The ReZA method goes digital, p.60 13) Haptic interface for spatial audio web player, p.6

Modeling electricity spot prices using mean-reverting multifractal processes

We discuss stochastic modeling of volatility persistence and anti-correlations in electricity spot prices, and for this purpose we present two mean-reverting versions of the multifractal random walk (MRW). In the first model the anti-correlations are modeled in the same way as in an Ornstein-Uhlenbeck process, i.e. via a drift (damping) term, and in the second model the anti-correlations are included by letting the innovations in the MRW model be fractional Gaussian noise with H < 1/2. For both models we present approximate maximum likelihood methods, and we apply these methods to estimate the parameters for the spot prices in the Nordic electricity market. The maximum likelihood estimates show that electricity spot prices are characterized by scaling exponents that are significantly different from the corresponding exponents in stock markets, confirming the exceptional nature of the electricity market. In order to compare the damped MRW model with the fractional MRW model we use ensemble simulations and wavelet-based variograms, and we observe that certain features of the spot prices are better described by the damped MRW model. The characteristic correlation time is estimated to approximately half a year.Comment: 13 pages, 4 figures, 2 table

Dynamics of two laterally coupled semiconductor lasers: strong- and weak-coupling theory.

Copyright © 2008 The American Physical SocietyThe stability and nonlinear dynamics of two semiconductor lasers coupled side to side via evanescent waves are investigated by using three different models. In the composite-cavity model, the coupling between the lasers is accurately taken into account by calculating electric field profiles (composite-cavity modes) of the whole coupled-laser system. A bifurcation analysis of the composite-cavity model uncovers how different types of dynamics, including stationary phase-locking, periodic, quasiperiodic, and chaotic intensity oscillations, are organized. In the individual-laser model, the coupling between individual lasers is introduced phenomenologically with ad hoc coupling terms. Comparison with the composite-cavity model reveals drastic differences in the dynamics. To identify the causes of these differences, we derive a coupled-laser model with coupling terms which are consistent with the solution of the wave equation and the relevant boundary conditions. This coupled-laser model reproduces the dynamics of the composite-cavity model under weak-coupling conditions

Locking bandwidth of two laterally coupled semiconductor lasers subject to optical injection

We report here for the first time (to our knowledge), a new and universal mechanism by which a two-element laser array is locked to external optical injection and admits stably injection-locked states within a nontrivial trapezoidal region. The rate equations for the system are studied both analytically and numerically. We derive a simple mathematical expression for the locking conditions, which reveals that two parallel saddle-node bifurcation branches, not reported for conventional single lasers subject to optical injection, delimit the injection locking range and its width. Important parameters are the linewidth enhancement factor, the laser separation, and the frequency offset between the two laterally-coupled lasers; the influence of these parameters on locking conditions is explored comprehensively. Our analytic approximations are validated numerically by using a path continuation technique as well as direct numerical integration of the rate equations. More importantly, our results are not restricted by waveguiding structures and uncover a generic locking behavior in the lateral arrays in the presence of injection

Modulation properties of solitary and optically injected phased-array semiconductor lasers

We study modulation properties of two-element phased-array semiconductor lasers that can be described by coupled mode theory. We consider four different waveguide structures and modulate the array either in phase or out of phase within the phase-locked regions, guided by stability diagrams obtained from direct numerical simulations. Specifically, we find that out-of-phase modulation allows for bandwidth enhancement if the waveguide structure is properly chosen; for example, for a combination of index antiguiding and gain-guiding, the achievable modulation bandwidth in the case of out-of-phase modulation could be much higher than the one when they are modulated in phase. Proper array design of the coupling, controllable in terms of the laser separation and the frequency offset between the two lasers, is shown to be beneficial to slightly improve the bandwidth but not the resonance frequency, while the inclusion of the frequency offset leads to the appearance of double peak response curves. For comparison, we explore the case of modulating only one element of the phased array and find that double peak response curves are found. To improve the resonance frequency and the modulation bandwidth, we introduce simultaneous external injection into the phased array and modulate the phased array or its master light within the injection locking region. We observe a significant improvement of the modulation properties, and in some cases, by modulating the amplitude of the master light before injection, the resulting 3 dB bandwidths could be enhanced up to 160 GHz. Such a record bandwidth for phased-array modulation could pave the way for various applications, notably optical communications that require high-speed integrated photonic devices