Presentation as a Form of Realizing Mutual Learning in Virtual Time

This article aims to show that presentation is one of the ways to implement peer learning by demonstrating aspects of self-organization and dialogue, which are absent in the most stable classroom pedagogical teaching model The author discussed the public speaking practice using presentations in the study of a foreign language as an opportunity to apply the method of mutual learning in the digital age, including in the context of distance learning The paper also analyses the available software applications for developing presentation skills and engaging the audience in discussion The experience of working with students in a non-linguistic university on presentations is described as an example of mutual learning, demonstrating aspects of self-organization and dialogue.

On the Functional Features of Acronyms and Abbreviations in On-Line Discourse

It has been established that such important factors as social, cultural, gender, etc. factors have a great impact on the creation of virtual reality. Recent studies have shown that the choice of linguistic and multilingual means depends, to a considerable extent, on the communicative strategies and mechanisms adopted by the language users. In the present article, the authors focus is on the functionality of different contractions and acronyms, which are widely used in online and offline communication, and are closely related to the all-important question of virtual time and space saving. The application of the cotextual descriptive method with a particular attention to the field of cotext and context knowledge in speech analysis allows the authors to emphasize the decisive role of the quantitative և qualitative uses of abbreviations in identifying the users' social and cultural characteristics.

M-ary nonlinear sine chirp spread spectrum for underwater acoustic communication based on virtual time-reversal mirror method

Linear chirp spread spectrum technique is widely used in underwater acoustic communication because of their resilience to high multipath and Doppler shift. Linear frequency modulated signal requires a high spreading factor to nearly reach orthogonality between two pairs of signals. On the other hand, nonlinear chirp spread spectrum signals can provide orthogonality at a low spreading factor. As a result, it improves spectral efficiency and is more insensitive to Doppler spread than the linear counterpart. To achieve a higher data rate, we propose two variants (half cycle sine and full cycle sine) of the M-ary nonlinear sine chirp spread spectrum technique based on virtual time-reversal mirror (VTRM). The proposed scheme uses different frequency bands to transmit chirp, and VTRM is used to improve the bit error rate due to high multipath. Its superior Doppler sensitivity makes it suitable for underwater acoustic communication. Furthermore, the proposed method uses a simple, low-power bank of matched filters; thus, it reduces the overall system complexity. Simulations are performed in different underwater acoustic channels to verify the robustness of the proposed scheme.

The effect of stress on memory for temporal context: an exploratory study

ABSTRACTTrauma memories can appear dissociated from their original temporal context, and are often relived as they occur in the here-and-now. Potentially these temporal distortions already occur during encoding of the aversive experience as a consequence of stress. Here, 86 participants were subjected to either a stress or control induction, after which they learned the temporal structure of four virtual days. In these virtual days, time was scaled and participants could use clock cues to construe the passage of time within a day. We examined whether stress causes a shift in the learning strategy from one based on virtual time to one based on event sequence. Our results do not show a discernible impact of stress on memory for temporal context, in terms of both sequence memory and more fine-grained representations of time. The stress groups showed more extreme performance trajectories, either good or poor, across all measures. However, as time estimations were overall quite poor it is unclear to what extent this reflected a true strategy shift. Future avenues of research that can build on these findings are discussed.

Distributed Virtual Time-Based Synchronization for Simulation of Cyber-Physical Systems

Our world today increasingly relies on the orchestration of digital and physical systems to ensure the successful operations of many complex and critical infrastructures. Simulation-based testbeds are useful tools for engineering those cyber-physical systems and evaluating their efficiency, security, and resilience. In this article, we present a cyber-physical system testing platform combining distributed physical computing and networking hardware and simulation models. A core component is the distributed virtual time system that enables the efficient synchronization of virtual clocks among distributed embedded Linux devices. Virtual clocks also enable high-fidelity experimentation by interrupting real and emulated cyber-physical applications to inject offline simulation data. We design and implement two modes of the distributed virtual time: periodic mode for scheduling repetitive events like sensor device measurements, and dynamic mode for on-demand interrupt-based synchronization. We also analyze the performance of both approaches to synchronization including overhead, accuracy, and error introduced from each approach. By interconnecting the embedded devices’ general purpose IO pins, they can coordinate and synchronize with low overhead, under 50 microseconds for eight processes across four embedded Linux devices. Finally, we demonstrate the usability of our testbed and the differences between both approaches in a power grid control application.

MODELAREA ÎN MATLAB/SIMULINK A FUNCȚIONĂRII UNUI VEHICUL ELECTRIC ÎN DIFERITE CICLURI DE ACȚIONARE

Through this paper, we want to improve the methods of dynamic design of electric vehicles, by creating simulation models in Simulink. The models are represented by simulation schemes that consist of blocks of mathematical operators, interconnected based on mathematical calculation formulas. The initial input sizes, specified in Table 1, can be easily modified, giving the possibility to obtain several models for different design ideas. The results of the simulations are materialized in graphical diagrams and provide virtual time data on vehicle speed, acceleration, engine torque, wheel power, energy consumed, and distance traveled. In the first simulation scheme, the input variable shows a motor torque generator with values between 0-132 Nm. In the second simulation scheme, the input variable is speed, according to the ECE-15 urban cycle scenario.