Jean Botev

• Dr.
• Senior Researcher | Head of the VR/AR Lab at University of Luxembourg

Achieving a high level of immersion and adaptation in virtual reality (VR) requires precise measurement and representation of user state. While extrinsic physical characteristics such as locomotion and pose can be accurately tracked in real-time, reliably capturing mental states is more challenging. Quantitative psychology allows considering more i...

This study investigates the impact of different gravitational physics on virtual tool embodiment and examines whether cognitive load predicts the emergence of ownership and agency. We hypothesize that low-gravity environments enhance the sense of tool embodiment and that this enhancement correlates with reduced cognitive load. To this end, we devis...

Achieving a high level of immersion and adaptation in virtual reality (VR) requires precise measurement and representation of user state. While extrinsic physical characteristics such as locomotion and pose can be accurately tracked in real-time, reliably capturing mental states is more challenging. Quantitative psychology allows considering more i...

In recent years, extended reality (XR) technologies have been increasingly used as a research tool in behavioral studies. They allow experimenters to conduct user studies in simulated environments that are both controllable and reproducible across participants. However, creating XR experiences for such studies remains challenging, particularly in n...

With recent advances in artificial intelligence and the metaverse, virtual agents have become increasingly autonomous and accessible. Due to their growing technological capabilities, interaction with virtual agents gradually evolves from a traditional user-tool relationship to one resembling interpersonal delegation, where users entrust virtual age...

Time experience is an essential part of one’s perception of any environment, real or virtual. In this paper, from a virtual environment design perspective, we explore how rhythmic stimuli can influence an unrelated cognitive task regarding time experience and performance in virtual reality. The task involves sorting 3D objects by shape, with varyin...

Interacting with virtual agents in immersive settings is becoming increasingly common thanks to the proliferation of dedicated media devices, such as consumer-grade virtual and augmented reality headsets. These technologies offer many advantages, e.g., in terms of presence and engagement, and can impact user behavior and attitudes toward virtual ag...

This paper presents the Rallye Platform, a software ecosystem that enables various mobile location-based serious games such as digital treasure hunts. Such games are an effective way to engage audiences in a cultural heritage context on-site, and beyond traditional museum spaces. We devised and employed the platform to develop two long-running depl...

Note-taking apps on tablets are increasingly becoming the go-to space for managing learning material as a student. In particular, digital note-taking presents certain advantages over traditional pen-and-paper approaches when it comes to organizing and retrieving a library of notes thanks to various search functionalities. This paper presents improv...

Intelligent autonomous agents (IAA) are proliferating and rapidly evolving due to the exponential growth in computational power and recent advances, for instance, in artificial intelligence research. Ranging from chatbots, over personal virtual assistants and medical decision-aiding systems, to self-driving or self-piloting systems, whether unbekno...

Student response systems (SRS) are a popular and effective tool to promote active learning on site, improving student engagement and attention, motivation and learning performance. Traditionally, SRS are designed for on-site settings. However, the safety measures in relation to the recent COVID-19 pandemic result in remote teaching at an unpreceden...

Social robots have an enormous potential for educational applications and allow for cognitive outcomes that are similar to those with human involvement. Remotely controlling a social robot to interact with students and peers in an immersive fashion opens up new possibilities for instructors and learners alike. Using immersive approaches can promote...

The research initiative “self-improving system integration” (SISSY) was established with the goal to master the ever-changing demands of system organisation in the presence of autonomous subsystems, evolving architectures, and highly-dynamic open environments. It aims to move integration-related decisions from design-time to run-time, implying a fu...

Social robots have an enormous potential for educational applications, allowing cognitive outcomes similar to those with human involvement. Enabling instructors and learners to directly control a social robot and immersively interact with their students and peers opens up new possibilities for effective lesson delivery and better participation in t...

With the coming of age of virtual/augmented reality and interactive media, numerous definitions, frameworks, and models of immersion have emerged across different fields ranging from computer graphics to literary works. Immersion is oftentimes used interchangeably with presence as both concepts are closely related. However, there are noticeable int...

With the coming of age of virtual/augmented reality and interactive media, numerous definitions, frameworks, and models of immersion have emerged across different fields ranging from computer graphics to literary works. Immersion is oftentimes used interchangeably with presence as both concepts are closely related. However, there are noticeable int...

The recent generation of mobile devices brings the necessary processing power, sensorics and other hardware to enable highly interactive and immersive mixed reality experiences. However, existing applications mainly focus on single users or the individual experience, and are often limited to basic user-device interaction. This paper discusses an im...

Document collections in e-learning can cause issues to both learners and teachers. On one hand, inquiry from the vast corpus of available resources is non-trivial without adequate formulation support and semantic information. Implicit links between documents are hardly understood without a proper visualization. On the other hand, it is difficult fo...

The ever-growing set of learning material challenges both students and teachers. While students often need to quickly retrieve resources on a certain topic, teachers have to author high quality documents in a limited amount of time, preferably using their favourite tools. In this paper, we propose an open ecosystem of plugins for popular authoring...

The active examination of a specific subject is essential for an effective learning experience and memory retention. Mobile, technology-driven exploration settings particularly suggest themselves for tapping into the potential of visual reinforcement and the generation effect in order to help establish relevant knowledge. In this paper, we introduc...

In human society, individuals have long voluntarily organized themselves in groups, which embody, provide and/or facilitate a range of different social concepts, such as governance, justice, or mutual aid. These social groups vary in form, size, and permanence, but in different ways provide benefits to their members. In turn, members of these group...

Semantic web technologies such as ontologies can foster the reusability of learning material by introducing common sets of concepts for annotation purposes. However, suggesting learning material from an open, heterogeneous corpus is a nontrivial problem. In this paper, we propose an extensible and lightweight modular ontology for programming educat...

Translating user motion into seamless input is a key concern for virtual reality-based applications. The level of immersion stands or falls both on the accuracy and immediacy of motion sensing, which applies in particular to distributed virtual environments where users interact and collaborate with each other. However, integrating precise gestural...

Student response systems as an active learning strategy have shown to be useful in different study domains. With the advent of gamification, these environments have become very popular to improve student engagement. However, existing solutions only provide a static set of activity types and limit their use to classrooms. In this paper, we present Y...

This paper introduces the CollaTrEx framework for collaborative context-aware mobile exploration and training. It is particularly designed for the in-situ collaboration within groups of learners performing together diverse educational activities to explore their environment in a fun and intuitive way. Aside from employing both absolute and relative...

The retrieval of appropriate learning material from a heterogeneous, open corpus is a challenge in project-based learning. In addition, with the authoring of high-quality learning resources being a time-intensive task, reusability in different contexts is desirable. In this paper, we propose to move from a material-centric to a student-centric appr...

Hybrid societies are self-organizing, collective systems, which are composed of different components, for example, natural and artificial parts (bio-hybrid) or human beings interacting with and through technical systems (socio-technical). Many different disciplines investigate methods and systems closely related to the design of hybrid societies. A...

In distributed collaborative document authoring environments, the preservation of a globally consistent data state is an important factor. However, synchronization conflicts are unavoidable and constitute a serious challenge. Our advanced compound document system provides the basis for a novel consistency management approach, in particular regardin...

This paper discusses a socio-aware approach inspired by structural balance theory for optimizing connectivity in peer-to-peer massively multiuser virtual environments. The sensible reduction of edges in geometric overlays that are integral to such systems is crucial for their scalability and efficiency in light of critical surges and other exigenci...

Compound documents in desktop environments face many issues and limitations in terms of modularity and genericity with regard to their representation and handling. The Snippet Platform natively supports highly dynamic and interactive compound documents. The contents of a document are not limited to combinations of traditional types like text, image...

Collective decision-making is a key concern for every social group; the clarity, effectiveness and participatory characteristics of the process are central to democratic societies and procedures.Networked computer systems in general and the increasing attention to social aspects in their purpose and design offer the individual novel means for parti...

This paper proposes a novel approach for enhancing document excerpts with semantic structures that are treated as first-class citizens, i.e., integrated at the system level. Providing support for semantics at the system level is in contrast with existing solutions that implement semantics as an add-on using intermediate descriptors. A framework and...

This paper presents the Snippet System, a new operating system environment that aims at providing enhanced document management facilities. For this, the proposed system utilizes a novel document model based on finer-grained entities, so-called Snippets. These support Relations, which capture the context of individual document excerpts. Snippets fur...

This paper presents the Snippet System, a new operating system environment that aims at providing enhanced document management facilities. For this, the proposed system utilizes a novel document model based on finer-grained entities, so-called Snippets. These support Relations, which capture the context of individual document excerpts. Snippets fur...

The expedient design of resource allocation mechanisms, particularly in light of dynamically varying user densities, is an important building block for the provision of peer-to-peer massively multiuser virtual environments. In case of their decentralized operation, a meaningful analysis of a given mechanism is difficult to achieve. The most realist...

A new generation of networked applications and social utilities, originating inter alia from the ongoing trend towards high-performance mobile devices, tightens exigencies relative to the processing of sensitive data. However, in order to ensure their correct operation, many of these applications require such information to be exchanged, and thus n...

Immersive Massive Multiuser Virtual Environments currently attract a lot of attention. Going beyond the hype, one discovers interesting concepts and opportunities for a supposed future Web which is commonly called the 3D Web. The global provision of such a vision is much more than another evolutionary step in content visualization, rather severe te...

When dealing with dynamic large-scale topologies such as those underlying Peer-to-Peer (P2P) Distributed Virtual Environments (DVEs), one inescapably reaches the point where either: a) simulations lack human behaviour and assessment or where b) practical experiments on a small scale do not yield significant results. The restrictions resulting from...

In this article, we present and evaluate an epidemic scheme for the synchronization of coupled Kuramoto oscillators in communication networks. It addresses the problem of efficiently providing globally synchronous time epochs in complex, dynamic Peer-to-Peer network topologies. Rather than the usual model of continuously coupled nodes, a discretize...

With the growth of Massively Multiuser Virtual Environments (MMVEs) and increasingly interactive social net working platforms, it is widely accepted that their convergence renders today's centralized hosting approaches impracticable. To handle virtual environments of such massive scale, decentralized systems are necessary that also involve the reso...

Due to the huge amount of available information in today's society, it becomes more and more difficult for the consumer to locate the most useful information for a specific topic. Recommender systems using collaborative filtering (CF) are a popular technique for reducing information overload and finding useful information on the Internet. However,...

The idea of the 3D Web as a global scale Distributed Vir- tual Environment (DVE) currently is very popular and a lot of research work is done in this field. In the course of the HyperVerse project we have developed a two-tier Peer-To- Peer (P2P) architecture as basic infrastructure for a feder- ated, open and scalable 3D Web. Our approach relies on...

In distributed virtual environments, where avatars permanently change their properties (e.g. their position) or perform modifications on shared objects, inconsistent states may occur due to message latency or concurrent updates. Here, the consistency often falls prey to high interactivity and responsiveness demands. To minimize the presence of inco...

In this article we evaluate an epidemic algorithm for the synchronization of coupled Kuramoto oscillators in complex Peer-to-Peer topologies. The algorithm requires a periodic coupling of nodes to a single random one-hop-neighbor. The strength of the nodes' couplings is given as a function of the degrees of both coupling partners. We study the emer...

During the last few years the application scope of peer-to-peer systems has been notably extended. While the problems of scalable data localization have been exhaustively addressed, one may notice that the problem of multicast cost and latency delays in very large, global scale peer-to-peer networks still remains inadequately considered. Many large...

Looking at the evolution of the Internet in recent years one can observe that massive multiuser virtual environments(MMVEs) have grown increasingly popular. Especially the idea of a rdquo3D Webrdquo as a combination of a MMVE and todaypsilas WWW provides a lot of exciting opportunities in terms of user experience and interactivity. From an infrastr...

The ever-increasing amount of available information in today's digital society necessitates inline techniques for determining the most relevant content. Collaborative filtering (CF) systems have proven to be an adequate means for reducing informational overload and generating useful recommendations. Current systems are predominantly built on centra...

Distributed virtual environments like online games or 3D virtual worlds have become very popular in the last few years and a more substantial surge in popularity and use is expected. Because of the huge number of users, such environments will undergo a change of infrastructure from a centralized to a decentralized one, making higher demands on cons...

Massive Multiuser Virtual Environments (MMVEs) and especially the idea of a "3D Web" as a combination of a MMVE and today's WWW currently attracts a lot of attention. The realization of such a vision on a global scale though poses severe technical challenges to the underlying network infrastructure. It is generally accepted that such a global scale...

Distributed Virtual Environments (DVEs) have grown popular in various fields of application. Apart from providing great collaborational opportunities in an immersive setting, large-scale DVEs pose severe scalability challenges. Although P2P approaches have proven to be effective for tackling many of these issues, still load delay problems remain in...

Recent research in the field of complex networks has shown that - beyond microscopic structural qualities - global statistical parameters are sufficient to describe a surprising number of their macroscopic properties. This article argues that such statistical parameters can be monitored by nodes in a decentralized and efficient way. The so achieved...

Abstract—The,vision of a “3D Web” as a combination,of massive online virtual environments,and today’s WWW,currently attracts a lot of attention. While it provides,a multitude,of opportunities, the realization of this vision on a global scale poses severe technical challenges. This work-in-progress paper intends to point out some,of the major,challe...

A substantial number of massive large-scale applications re- quire scalable underlying network topologies. Nowadays structured Peer-to-Peer overlay networks meet these require- ments very well. But there is still a need to decide which of these overlay networks is most suitable for providing the best possible performance for a certain application....

In order to realistically simulate algorithms or evaluate P2P overlay topologies, a detailed model of the underlying router topology is required. Since actively measuring this topology is extremely laborious and furthermore a waste of network resources, traditionally topology generators are used in order to create synthetic router-level graphs. For...