György Wersényi

6506858994

Publications - 51

Effectiveness of High-Intensity Therapy in Rehabilitation of Parkinson’s Disease Patients

József Tollár Péter Prukner Istvan Drotar Nándor Prontvai Szilvia Kóra Petra Kós György Wersényi

Publication Name: Applied Sciences Switzerland

Publication Date: 2025-06-01

Volume: 15

Issue: 11

Page Range: Unknown

Description:

Parkinson’s disease (PD) is a progressive movement disorder with no cure. In this randomized controlled study, 100 patients with PD were assigned to four intervention groups (Exergame, Cycling, Agility, and Robot) for 14 weeks. This study evaluates the effectiveness of high-intensity therapy in a randomized clinical trial. Exergaming, cycling, agility, and robot therapies improved motor function, postural stability, and cardiovascular health. Heart rate monitoring and Borg Scale ratings confirmed the safety and adaptability of high-intensity training, with patients sustaining moderate-to-high exertion without adverse effects. Significant improvements were observed in gait speed (+0.30–0.50 m/s), Functional Independence Measure (FIM) (+25–30 points), and Berg Balance Scale scores. Integrating high-intensity, functional movement-based therapies into PD rehabilitation may offer superior motor, gait, and cardiovascular benefits compared to conventional methods.

Open Access: Yes

DOI: 10.3390/app15115890

Comparison of Five Rehabilitation Interventions for Acute Ischemic Stroke: A Randomized Trial

Tamás Haidegger Tibor Hortobágyi József Tollár Péter Prukner Tomas Vetrovsky Istvan Drotar Szilvia Kóra Petra Kós Zoltán Vadászi György Wersényi

Publication Name: Journal of Clinical Medicine

Publication Date: 2025-03-01

Volume: 14

Issue: 5

Page Range: Unknown

Description:

Background: Comparative efficacy of rehabilitation interventions in persons with acute ischemic stroke (PwS) is limited. This randomized trial assessed the immediate and lasting effects of five interventions on clinical and mobility outcomes in 75 PwS. Methods: Five days after stroke, 75 PwS were randomized into five groups: physical therapy (CON, standard care, once daily); walking with a soft robotic exoskeleton (ROB, once daily); agility exergaming once (EXE1, once daily) or twice daily (EXE2, twice daily); and combined EXE1+ROB in two daily sessions. Interventions were performed 5 days per week for 3 weeks. Outcomes were assessed at baseline, post-intervention, and after 5 weeks of detraining. Results: Modified Rankin Scale (primary outcome) and Barthel Index showed no changes. EXE1, EXE2, ROB, and EXE1+ROB outperformed standard care (CON) in five secondary outcomes (Berg balance scale, 10m walking speed, 6-min walk test with/without robot, standing balance), with effects sustained after 5 weeks. Dose effects (EXE1 vs. EXE2) were minimal, while EXE1+ROB showed additive effects in 6-min walk tests. Conclusions: These novel comparative data expand evidence-based options for therapists to design individualized rehabilitation plans for PwS. Further confirmation is needed.

Open Access: Yes

DOI: 10.3390/jcm14051648

Comparison of Auditory and Visual Short-Term Memory Capabilities using a Serious Game Application

Aádám Csapó György Wersényi

Publication Name: Infocommunications Journal

Publication Date: 2024-06-01

Volume: 16

Issue: 2

Page Range: 51-60

Description:

A comprehensive serious game application has been designed and implemented to examine the capacity and effective- ness of short-term auditory and visual memory, otherwise known as working memory in human subjects. Participants engaged in an adaptation of the well-known paired association game that entails turning over cards and recalling their placement within a 2D matrix structure of various resolutions. Each trial introduced either visual icons (vision-only condition) or auditory objects (audio-only condition). User performance was evaluated through a detailed statistical analysis focusing only on the highest 6x8 resolution condition in the application. Findings suggest that visual memory did not conclusively outperform auditory memory in the context of this game. However, within the scope of auditory stimuli, familiar iconic sounds, such as excerpts of speech and commonplace sounds, were recalled more effectively than unfamiliar, synthetic sounds like parametric waveforms. Furthermore, performance appeared to be influenced by demographic factors, with male and younger subjects yielding superior results.

Open Access: Yes

DOI: 10.36244/ICJ.2024.2.7

Sustainable Solutions in Rehabilitation Engineering: Manufacturing of Outer Ear Replicas with Current 3D Technology

György Wersényi

Publication Name: Studies in Systems Decision and Control

Publication Date: 2024-01-01

Volume: 545

Issue: Unknown

Page Range: 323-331

Description:

A workflow pipeline has been constructed and tested for rapid prototyping of outer ear replicas, incorporating 3D scanning, image post-processing, and 3D printing using various synthetic materials. Handheld and volumetric scanners, open-source software solutions, and the availability of 3D printers make time- and cost-effective procedures already possible. The demonstrated solutions may extend or replace expensive tissue engineering methods; thus, they can contribute to new business models and sustainability in facial reconstruction surgery. This allows not only for aesthetic improvement of the patients but also for the restoration of acoustic properties of the outer ears.

Open Access: Yes

DOI: 10.1007/978-3-031-65203-5_29

Measurement Setup Considerations for Investigating Health Effects of 5G Exposure

Oliver Takacs György Wersényi

Publication Name: 2024 IEEE International Conference on Microwaves Communications Antennas Biomedical Engineering and Electronic Systems Comcas 2024

Publication Date: 2024-01-01

Volume: Unknown

Issue: Unknown

Page Range: Unknown

Description:

The proliferation of 5G technology requires the installation of new radio frequency equipment (antennas, base stations) next to the existing 4G network elements. New frequency bands have been allocated and opened for 5G services in the lower and higher GHz bands. Due to the lack of reliable and conclusive experiments and the uncontrolled spread of false information via media and social networks on the internet, a never seen before resistance has arisen from the public. Although many papers have recently been published suggesting adverse health effects, most of them were inadequately designed, conducted, and evaluated in order to be conclusive. Nevertheless, there is a need for proper experiments. This paper highlights current results, emerging critics, and presents a recommendation for further investigation.

Open Access: Yes

DOI: 10.1109/COMCAS58210.2024.10666173

Cost-effective 3D scanning and printing technologies for outer ear reconstruction: current status

Verena Scheper Simone Spagnol Thomas Eixelberger György Wersényi Thomas Wittenberg

Publication Name: Head and Face Medicine

Publication Date: 2023-12-01

Volume: 19

Issue: 1

Page Range: Unknown

Description:

Current 3D scanning and printing technologies offer not only state-of-the-art developments in the field of medical imaging and bio-engineering, but also cost and time effective solutions for surgical reconstruction procedures. Besides tissue engineering, where living cells are used, bio-compatible polymers or synthetic resin can be applied. The combination of 3D handheld scanning devices or volumetric imaging, (open-source) image processing packages, and 3D printers form a complete workflow chain that is capable of effective rapid prototyping of outer ear replicas. This paper reviews current possibilities and latest use cases for 3D-scanning, data processing and printing of outer ear replicas with a focus on low-cost solutions for rehabilitation engineering.

Open Access: Yes

DOI: 10.1186/s13005-023-00394-x

Outer ear reconstruction using 3D technology Materials, methods and applicability in use cases

György Wersényi Balázs Gasz

Publication Name: Current Directions in Biomedical Engineering

Publication Date: 2023-09-01

Volume: 9

Issue: 1

Page Range: 1-4

Description:

Manufacturing replicas for replacing missing or defective body parts also incorporates 3D technology, including scanning, image processing and printing. In the case of the ears, both aesthetics and functionality play a significant role. Based on these techniques, outer ear replicas were produced using 3D scans of human skulls in a rapid prototyping procedure for actual patients. Hand-held scanners delivered accurate images for post-processing of the mesh and for printing in a cost- and time efficient way. Use cases of patients demonstrate applicability, allowing the technology to be available also for the general population in the future.

Open Access: Yes

DOI: 10.1515/cdbme-2023-1001

The Vision that Carries the Digital Transformation on Its Back—The Promises of 5G for Sustainability and for the Corporate Sector Focusing on the SMEs in Hungary

Árpád Tóth Áron Gyimesi György Wersényi

Publication Name: Springer Proceedings in Business and Economics

Publication Date: 2023-01-01

Volume: Unknown

Issue: Unknown

Page Range: 119-144

Description:

Digital transformation, including emerging telecommunication technologies, can be a game changer in the case of SMEs. 5G technology paves the way to substitute different expansive communication technologies, becoming the backbone of i4.0 solutions. Although companies declare the importance of digital transformation, 5G is not necessarily part of it. Especially, SMEs are uncertain about 5G. This paper highlights the business model opportunities and benefits of utilizing this disruptive technology. We analyze the 5G awareness of Hungarian SMEs based on a survey targeting their digital transformation. Hungarian SMEs have significant unawareness regarding the technical issues and the business manners as well. Providing information and guidance based on governmental funding is expected and required.

Open Access: Yes

DOI: 10.1007/978-981-19-8485-3_5

COMPARISON OF TRANSFER FUNCTIONS OF OPEN EAR CANAL HEADSETS MEASURED ON A DUMMY-HEAD AND A HUMAN HEAD

György Wersényi

Publication Name: Proceedings of Forum Acusticum

Publication Date: 2023-01-01

Volume: Unknown

Issue: Unknown

Page Range: Unknown

Description:

Headsets that leave the ear canal open are used where environmental noise and acoustical information have to be maintained, while additional sound transmission is also required. Besides classical supra aural and in-ear phones having “hear through” functions, bone conduction and “tube-like” headsets inserted in the ear canal can be used. Usually, the transfer parameters of these devices are inferior to traditional headphones, providing decreased sound quality, sensitivity and speech intelligibility. Two different commercially available bone conduction headphones, an in-ear tube type earphone and supra aural models were tested using a dummy-head and a real human head for comparison. Measured transfer functions show the limited frequency range of open ear canal models that restricts the accessibility of such devices. Variability in repeated measurements is relatively large. Standardization of the measurement procedure for bone conduction headsets is needed, where the inclusion of human subjects can be considered.

Open Access: Yes

DOI: DOI not available

Evaluation of Bone Conduction and Active-Noise-Cancellation Headsets Based on Listening Tests in a Virtual Environment

György Wersényi

Publication Name: Infocommunications Journal

Publication Date: 2023-01-01

Volume: 15

Issue: 3

Page Range: 54-62

Description:

Alternative design headsets incorporating activenoise-cancellation or bone conduction were evaluated in listening tests in a virtual reality environment. Virtual sound sources in the horizontal plane had to be identified using stereo panning in the frontal hemisphere. In addition, transfer characteristics and damping effects were measured with a dummy-head. Results indicate that up to five source locations can be used in real applications with high accuracy in virtual scenarios, independent of the spectral content of the excitation signals. Furthermore, the use of noise cancellation in presence of 80 dB background noise does not improve performance. Commercially available bone conduction headsets can provide the same detection accuracy even if the subjective sound quality is lower.

Open Access: Yes

DOI: 10.36244/ICJ.2023.3.6

TACTILE DISCRIMINATION USING A 2-CHANNEL VIBRATION SYSTEM ON DIFFERENT BODY PARTS

György Wersényi

Publication Name: Proceedings of Forum Acusticum

Publication Date: 2023-01-01

Volume: Unknown

Issue: Unknown

Page Range: Unknown

Description:

A multichannel tactile feedback system was developed to test human subjects' sensitivity and discrimination ability using different vibration patterns. Small vibrating motors were attached to the body, and subjects reported on their sensation comparing the left and right side of the body (arms, ankles, and wrists) in a 2-channel signal presentation. Results showed that the most sensitive spot is the wrist position, followed by the ankles. Furthermore, changes in the vibration frequency are challenging to detect; thus, using different temporal patterns of the signals is more straightforward in an actual application.

Open Access: Yes

DOI: DOI not available

The Future of Health Management—How Virtual Reality and 5G Networks Can Contribute to Sustainability in Healthcare

József Tollár György Wersényi

Publication Name: Springer Proceedings in Business and Economics

Publication Date: 2023-01-01

Volume: Unknown

Issue: Unknown

Page Range: 459-470

Description:

Developments in healthcare usually directly target innovations in intervention techniques and medical devices for diagnosis, analysis and treatment. On the other hand, digital development in administration, handling and accessing (sensitive) patient data or real-time availability of information also contribute to improvement of management. The CoVid situation highlighted emerging technologies that covers both, and blurs the border between, management (i.e., cost reduction) and actual treatment. The newly introduced 5G New Radio wireless technology and the expansion of virtual, augmented and mixed reality applications not only assist medical personnel during treatment, but can increase safety, availability and sustainability of services, and at the same time, can reduce costs. This paper briefly introduces benefits of these technologies focusing on state-of-the-art use cases.

Open Access: Yes

DOI: 10.1007/978-981-19-8485-3_20

Telerehabilitation After Brain Injuries: Its Efficacy and Role in Reducing Healthcare Burdens

Tamás Haidegger József Tollár Péter Prukner Istvan Drotar Nándor Prontvai Blanka Törő Szilvia Kóra Petra Kós György Wersényi

Publication Name: Acta Polytechnica Hungarica

Publication Date: 2023-01-01

Volume: 20

Issue: 8

Page Range: 305-320

Description:

Rehabilitation following brain injuries, such as stroke and other traumatic injuries, presents significant challenges for both patients and healthcare systems. Traditional in-person rehabilitation often requires regular visits to specialized facilities, which can be difficult for patients in remote areas or those with mobility and financial constraints. Telerehabilitation offers a promising solution by enabling patients to continue essential therapy at home, ensuring continuity of care while reducing the burden on healthcare providers. It can be effectively applied across various patient groups, including children, adults, the elderly, amputees, individuals with traumatic neurological injuries, and those with neurocognitive impairments such as dementia. Our telemedicine platform integrates advanced technologies, i.e., 3D motion analysis and Virtual Reality (VR) to enhance home-based physiotherapy. These tools enable precise monitoring, real-time feedback, and immersive therapy sessions, in order to improve coordination, fine motor skills, hand-eye coordination, and the vestibular system, which is crucial for balance. This platform also performs detailed offline data analysis, allowing healthcare professionals to adjust therapy plans based on individual needs. As the demand for rehabilitation services continues to grow, adopting these technologies will be crucial for sustainable, effective healthcare, ultimately improving patient outcomes and shaping a more efficient and equitable future for healthcare systems.

Open Access: Yes

DOI: 10.12700/APH.20.8.2023.8.16

Virtual Reality in Cerebrovascular Rehabilitation: A Mini Review on Clinical Efficacy and Neurological Impacts

Tamás Haidegger József Tollár Péter Prukner Istvan Drotar Nándor Prontvai Blanka Törő Szilvia Kóra Petra Kós György Wersényi

Publication Name: Acta Polytechnica Hungarica

Publication Date: 2023-01-01

Volume: 20

Issue: 8

Page Range: 321-336

Description:

The application of virtual reality (VR) technology in both upper and lower limb rehabilitation represents a significant advancement in the field of medicine. VR-based therapies provide patients with the opportunity to engage in intensive, repetitive, and targeted exercises that promote neuroplasticity and improve the motor skills necessary for daily life. VR has long been recommended for the rehabilitation of conditions such as in case of ischemic stroke, Parkinson’s disease, and multiple sclerosis, further underscoring its versatility and therapeutic potential. In our study, we evaluated the effectiveness of VR therapy focusing on stroke rehabilitation. The reviewed VR systems provided motion analysis, tracking, feedback reinforcement, and realistic environments to facilitate the restoration of motor functions. Furthermore, we developed a VR-based therapy aimed at both upper and lower limb motor functions, combined with traditional rehabilitation. The application of VR technology not only promotes the improvement of motor functions but also offers economic advantages by reducing the burden on healthcare workers and increasing rehabilitation capacity. Further research is needed to determine the optimal conditions for applying VR therapy in clinical practice.

Open Access: Yes

DOI: 10.12700/APH.20.8.2023.8.17

Evaluation of the HoloLens for Medical Applications Using 5G-connected Mobile Devices

György Wersényi

Publication Name: Infocommunications Journal

Publication Date: 2022-12-01

Volume: 14

Issue: 4

Page Range: 11-17

Description:

The updated range of models of smart glasses has expanded the availability of augmented reality (AR) technology in a way that opens them up to several applications. The first prototypes have been replaced by new models and vendors offer off-the-shelf solutions. E-health and medical applications have been in focus from the start. Furthermore, the roll-out of 5G technology would enable almost real-time, high-speed and low- latency communication, which would expand the potential uses and ideas. This paper gives a short overview of the current state, focusing on medical applications using smart glasses. The HoloLens glasses were evaluated regarding latency and data rates by using WiFi and the 5G campus network of the university. Results show that the HoloLens may be used in education, training and teleassistance; however, assisting latency-sensitive tasks that require a reliable network connection, ergonomic design, and privacy issues still remain a problem.

Open Access: Yes

DOI: 10.36244/ICJ.2022.4.2

Perception Accuracy of a Multi-Channel Tactile Feedback System for Assistive Technology

György Wersényi

Publication Name: Sensors

Publication Date: 2022-11-01

Volume: 22

Issue: 22

Page Range: Unknown

Description:

Assistive technology uses multi-modal feedback devices, focusing on the visual, auditory, and haptic modalities. Tactile devices provide additional information via touch sense. Perception accuracy of vibrations depends on the spectral and temporal attributes of the signal, as well as on the body parts they are attached to. The widespread use of AR/VR devices, wearables, and gaming interfaces requires information about the usability of feedback devices. This paper presents results of an experiment using an 8-channel tactile feedback system with vibrators placed on the wrists, arms, ankles, and forehead. Different vibration patterns were designed and presented using sinusoidal frequency bursts on 2, 4, and 8 channels. In total, 27 subjects reported their sensation formally and informally on questionnaires. Results indicate that 2 and 4 channels could be used simultaneously with high accuracy, and the transducers’ optimal placement (best sensitivity) is on the wrists, followed by the ankles. Arm and head positions were inferior and generally inadequate for signal presentation. For optimal performance, signal length should exceed 500 ms. Furthermore, the amplitude level and temporal pattern of the presented signals have to be used for carrying information rather than the frequency of the vibration.

Open Access: Yes

DOI: 10.3390/s22228962

Technical Feasibility and Design Challenges of Unmanned Aerial Vehicle based Drive Testing on Cellular Networks

Oliver Takacs Istvan Drotar Tamas Kovacs György Wersényi

Publication Name: 2022 IEEE 1st International Conference on Internet of Digital Reality Iod 2022

Publication Date: 2022-01-01

Volume: Unknown

Issue: Unknown

Page Range: 23-32

Description:

Conventional drones are using ISM (Industrial, Scientific, and Medical) frequency bands during operation that can limit the range of the device. Limitations depend on the applied technologies in these frequency bands. With the help of cellular networks, BVLOS (Beyond Visual Line of Sight) UAV operations can be realized with increased safety. Unfortunately, base stations used in cellular networks target the lower, near-earth layers of air space. In case of drones, coverage in higher layers must be planned. Test procedures used in residential mobile network measurements record the quality parameters of the network measured on foot or by vehicle. Furthermore, the device carrying the measurement setup can cause serious interference with the measurement results. This paper presents current measurement methods and a concept for a solution to apply the measurement devices to an UAV. This new measurement method is correspondingly fit in the conception of IoD conference. We are executed the measurements by our own newly developed UAV system which can be a substitute solution of the walking measurements. Furthermore it provides opportunity to measurement some of that new layers of the air that have not had a chance before. Also, this innovation gives us the opportunity to perform measurements that have been difficult and dangerous so far, much easier and safer than before, without the need for human contact. In addition, measurements with drones have given a new perspective to the world of measurement methods.

Open Access: Yes

DOI: 10.1109/IoD55468.2022.9987208

Auditory and Haptic Solutions for Access and Feedback in Internet of Digital Reality Applications

Aádám Csapó György Wersényi

Publication Name: 2022 IEEE 2nd Conference on Information Technology and Data Science Citds 2022 Proceedings

Publication Date: 2022-01-01

Volume: Unknown

Issue: Unknown

Page Range: 319-323

Description:

The concept of Internet of Digital Reality (IoD) was introduced as the next level organization of cognitive entities following the concept of the Internet of Things (IoT) and Internet of Everything (IoE). As virtual-immersive environments are a fundamental component of IoD which allow human and non-human entities to interact in real time, the ability a wide range of communication modalities is crucial. This paper briefly presents the concept of IoD together with an overview of various I/O solutions for human users, with a focus on research directions and (re)emerging technologies in the near future.

Open Access: Yes

DOI: 10.1109/CITDS54976.2022.9914161

Health issues using 5G frequencies from an engineering perspective: Current review

György Wersényi

Publication Name: Open Engineering

Publication Date: 2022-01-01

Volume: 12

Issue: 1

Page Range: 1060-1077

Description:

The possible adverse health effects of electromagnetic field (EMF) exposure have been in research focus since radio waves were introduced to telecommunication. Broadcast radio systems, satellites, and mobile communication devices use different bands of the radio spectrum, antennas, modulations, and radiated power. The proliferation of cellular networks and mobile phones as user devices have brought transmitting and receiving antennas in the close proximity of the human body and the head. Hundreds of experiments have been conducted to prove and disprove adverse health effects of exposure. Literature reviews of experimental results have also followed the current developments in technology; however, an exhaustive analysis performed on the methodologies has revealed many flaws and problems. This article focuses on the latest results on frequency bands mostly used for 5G below and above 6 GHz in the mmWave band. Current results do not indicate significant health effects and responses below the current safety limits. Nevertheless, further research directions can be identified, especially for mmWave radiation.

Open Access: Yes

DOI: 10.1515/eng-2022-0387

Recommendations on electromagnetic compatibility testing of unmanned aerial vehicles

Miklós Kuczmann Gergely Friedl Zsombor Petho Mate Liszi György Wersényi

Publication Name: 2022 IEEE 1st International Conference on Internet of Digital Reality Iod 2022

Publication Date: 2022-01-01

Volume: Unknown

Issue: Unknown

Page Range: 39-44

Description:

In this paper several recommendations and considerations on electromagnetic compatibility (EMC) testing of unmanned aerial vehicles (UAV, or drone) are presented. Currently, the standardization of drone EMC measurements is not yet fully established. These products are usually tested according to EN 55032, EN 55024, EN 64000-4-3 and EN 61000-4-8, while the scope of these standards is not UAV specific. The focus of this paper is on the testability of UAV emission and immunity from various aspects. The main goal of this paper is to initiate discussions regarding UAV specific conditions to describe measurement setups, conditions, and limitations suitable to drones. First, the UAV and the test environment shall be prepared from safety ant testability point of view. These aspects and recommended conditions - e.g., drone fastening, applying artificial load, and emulating the Earth's magnetic field - are explained in this paper. While the drones are assembled from CE certified components, the whole product requires a system level validation. The test conditions, limits, and stress levels shall be aligned to the specific environment an UAV might be exposed to. An initiative study aiming to describe the UAV exclusive electromagnetic conditions are also presented here. Additionally, several key aspects for EMC engineering of UAV's are also discussed in this paper, mainly focusing on functionality relevant EMC issues and solutions.

Open Access: Yes

DOI: 10.1109/IoD55468.2022.9987138

Handheld 3D Scanning and Image Processing for Printing Body Parts - A Workflow Concept and Current Results

Anna Sudar György Wersényi Thomas Wittenberg

Publication Name: 2022 IEEE 1st International Conference on Internet of Digital Reality Iod 2022

Publication Date: 2022-01-01

Volume: Unknown

Issue: Unknown

Page Range: 61-68

Description:

The combination of current technical possibilities of handheld 3D scanning devices, 3D data analysis and interaction, and novel 3D bioprinting technologies has opened the way to develop workflows and scenarios for the generation of personalized human prosthesis. Specifically, using the human ear as one example to develop a cost-effective chain of methods and tools, the above mentioned combined and interacting technologies can be used to understand and demonstrate the possibilities for rapid bio prototyping. Production workflows for personalized soft-material bio-prosthesis gain significance in reconstructive and plastic surgery. This paper introduces a workflow concept, presents a list of appropriate and accessible state-of-the-art handheld scanners, followed by an image processing solution based on the MeshLab application and printing first prototypes.

Open Access: Yes

DOI: 10.1109/IoD55468.2022.9987113

Internet of digital reality: Infrastructural background – Part II

Aádám Csapó Tamás Budai György Wersényi P. Baranyi

Publication Name: Acta Polytechnica Hungarica

Publication Date: 2021-01-01

Volume: 18

Issue: 8

Page Range: 91-104

Description:

Internet of Digital Reality (IoD) is a concept that extends the Internet of Things (IoT) with the management, transmission and harmonization of digital realities. IoD covers aspects of connectivity, accessibility and usability with respect to different cognitive entities present in the digital world, via a confluence of technologies including virtual reality, artificial intelligence and 2D digital environments, in a way that recognizes human factors and cognitive aspects as key issues. Devices, interfaces, and interacting entities can be enabled through IoD to share digital realities and to thereby build a new level of reality, using intelligent connections mostly based on immersive virtual scenarios and multi-modal interactions in both public and private networks. In this paper, we look into the infrastructural requirements of and challenges behind the Internet of Digital Reality, which must be solved in order to deliver a high-quality user experience while keeping the increasing complexity of these networks at bay.

Open Access: Yes

DOI: 10.12700/APH.18.8.2021.8.5

Introducing the concept of internet of digital reality – part i

Aádám Csapó Tamás Budai György Wersényi P. Baranyi

Publication Name: Acta Polytechnica Hungarica

Publication Date: 2021-01-01

Volume: 18

Issue: 7

Page Range: 225-240

Description:

With the growing pervasiveness of Virtual Reality, Augmented Reality, Mixed Reality and Digital Twins combined with Artificial Intelligence, 5G networks and the omni-present 2D Web, we are entering into a new era, characterized by a multi-modal entangled combination of previously disparate realms of IT with human and social cognitive systems. This process of entanglement is arguably leading to a new, qualitatively different kind of reality, in which the bor-ders between the physical and digital world, as well as digital representations and simulations thereof are becoming increasingly fuzzy. Based on these developments, the paper re-interprets some well-known concepts – including virtual reality, augmented reality, mixed reality, as well as virtual / digital simulations and virtual / digital twins. Based on these new interpretations, the paper introduces the higher-level structures of Digital Reality (DR) and Internet of Digital Reality (IoD). It is argued that these structures can lead to a better understanding of the new possibilities afforded to humanity by pervasive digital technologies.

Open Access: Yes

DOI: 10.12700/APH.18.7.2021.7.12

Current use and future perspectives of spatial audio technologies in electronic travel aids

Runar Unnthorsson Michal Bujacz Alin Moldoveanu Simone Spagnol Marcelo Herrera Martinez Oana Bslan György Wersényi

Publication Name: Wireless Communications and Mobile Computing

Publication Date: 2018-01-01

Volume: 2018

Issue: Unknown

Page Range: Unknown

Description:

Electronic travel aids (ETAs) have been in focus since technology allowed designing relatively small, light, and mobile devices for assisting the visually impaired. Since visually impaired persons rely on spatial audio cues as their primary sense of orientation, providing an accurate virtual auditory representation of the environment is essential. This paper gives an overview of the current state of spatial audio technologies that can be incorporated in ETAs, with a focus on user requirements. Most currently available ETAs either fail to address user requirements or underestimate the potential of spatial sound itself, which may explain, among other reasons, why no single ETA has gained a widespread acceptance in the blind community.We believe there is ample space for applying the technologies presented in this paper, with the aim of progressively bridging the gap between accessibility and accuracy of spatial audio in ETAs.

Open Access: Yes

DOI: 10.1155/2018/3918284

Improving the audio game–playing performances of people with visual impairments through multimodal training

Runar Unnthorsson Alin Moldoveanu Hunor Nagy Oana Bălan György Wersényi Florica Moldoveanu

Publication Name: Journal of Visual Impairment and Blindness

Publication Date: 2017-03-01

Volume: 111

Issue: 2

Page Range: 148-164

Description:

Introduction: As the number of people with visual impairments (that is, those who are blind or have low vision) is continuously increasing, rehabilitation and engineering researchers have identified the need to design sensory-substitution devices that would offer assistance and guidance to these people for performing navigational tasks. Auditory and haptic cues have been shown to be an effective approach towards creating a rich spatial representation of the environment, so they are considered for inclusion in the development of assistive tools that would enable people with visual impairments to acquire knowledge of the surrounding space in a way close to the visually based perception of sighted individuals. However, achieving efficiency through a sensory substitution device requires extensive training for visually impaired users to learn how to process the artificial auditory cues and convert them into spatial information. Methods: Considering all the potential advantages game-based learning can provide, we propose a new method for training sound localization and virtual navigational skills of visually impaired people in a 3D audio game with hierarchical levels of difficulty. The training procedure is focused on a multimodal (auditory and haptic) learning approach in which the subjects have been asked to listen to 3D sounds while simultaneously perceiving a series of vibrations on a haptic headband that corresponds to the direction of the sound source in space. Results: The results we obtained in a sound-localization experiment with 10 visually impaired people showed that the proposed training strategy resulted in significant improvements in auditory performance and navigation skills of the subjects, thus ensuring behavioral gains in the spatial perception of the environment.

Open Access: Yes

DOI: 10.1177/0145482x1711100206

Contrasting results and effectiveness of controlled experiments with crowdsourced data in the evaluation of auditory reaction times

Aádám Csapó Hunor Nagy György Wersényi

Publication Name: 7th IEEE International Conference on Cognitive Infocommunications Coginfocom 2016 Proceedings

Publication Date: 2017-01-03

Volume: Unknown

Issue: Unknown

Page Range: 421-425

Description:

We developed an application for the Android platform to test reaction times to auditory stimuli on mobile devices. During tests, users were asked to respond as quickly as possible to auditory events provided through headphone playback, and to also identify the directions of those events based on stereo panning. This paper presents a comparative evaluation of data (i.e. response times in seconds and error rates) collected through controlled supervised experiments as opposed to a crowdsourcing based solution. It is demonstrated that in some respects, crowdsourced data and laboratory data show similar results within their own category, but that at the same time a statistical comparison between the two measurement configurations is difficult due to the significant amount of noisy (outlier) data in the crowdsourced case.

Open Access: Yes

DOI: 10.1109/CogInfoCom.2016.7804586

Evaluation of human-Myo gesture control capabilities in continuous search and select operations

Aádám Csapó Hunor Nagy György Wersényi Arni Kristjansson

Publication Name: 7th IEEE International Conference on Cognitive Infocommunications Coginfocom 2016 Proceedings

Publication Date: 2017-01-03

Volume: Unknown

Issue: Unknown

Page Range: 415-420

Description:

Tactile and haptic devices can be used to control and interact with a wide range of systems, including games, virtual environments and assistive technologies. Although many psychophysical studies have measured thresholds of human sensory capabilities for interpreting haptic and tactile feedback, relatively little is known about the precision with which we are able to guide the behavior of a system based on kinesthetic and myoelectric gestures. A broad study of the latter problem is important, especially now that a number of devices have appeared-such as the Leap Motion Controller and the Myo armband-which enable humans to use finger, hand and arm gestures to interact with the digital world. This paper provides a broad overview on the topic, and reports a set of preliminary experiments on the extent to which the Myo armband can be used to control auditory feedback in real time. Test results are evaluated based on a Bayesian statistical model of an empirical (but for the most part, unambiguous) performance scale. The goal is to investigate ways in which visually impaired users could use the Myo to control the output of an assistive technology.

Open Access: Yes

DOI: 10.1109/CogInfoCom.2016.7804585

Evaluation of training to improve auditory memory Capabilities on a mobile device based on a serious game application

Hunor Nagy György Wersényi

Publication Name: 142nd Audio Engineering Society International Convention 2017 AES 2017

Publication Date: 2017-01-01

Volume: Unknown

Issue: Unknown

Page Range: Unknown

Description:

Capabilities of the auditory memory system were tested in a serious game application developed for the Android mobile platform. Participants played the well-known game of finding pairs by flipping and remembering objects on cards arranged in a matrix structure. Visual objects were replaced by iconic auditory events (auditory icons, earcons). Total time and different error rates were recorded and the effect of training was also evaluated. Results indicate that training contributes to a better performance and human voice samples are the easiest to remember.

Open Access: Yes

DOI: DOI not available

Comparison of HRTFs from a dummy-head equipped with hair, cap and glasses in a virtual audio listening task over equalized headphones

József Répás György Wersényi

Publication Name: 142nd Audio Engineering Society International Convention 2017 AES 2017

Publication Date: 2017-01-01

Volume: Unknown

Issue: Unknown

Page Range: Unknown

Description:

Head-Related Transfer Functions (HRTFs) are frequently used in virtual audio scene rendering in order to simulate sound sources at different spatial locations. The use of dummy-head HRTFs (also referred as generic sets) is often criticized because of poor localization performance, leading to e.g. lower spatial resolution, in-thehead localization, front-back reversals etc. This paper presents results of horizontal plane localization obtained by digital filter representations of dummy-head HRTFs that were recorded normally, and using additional cap, glasses and hair on the head. Results of untrained subjects over equalized reference headphones showed no significant difference among the HRTF sets despite of large magnitude differences. This method for customization of generic HRTFs fails if improvement in localization is needed.

Open Access: Yes

DOI: DOI not available

Usability and effectiveness of auditory sensory substitution models for the visually impaired

Runar Unnthorsson Michal Bujacz Alin Moldoveanu Gabriel Ivanica Aádám Csapó Simone Spagnol Marcelo Herrera Martinez Maciej Janeczek György Wersényi

Publication Name: 142nd Audio Engineering Society International Convention 2017 AES 2017

Publication Date: 2017-01-01

Volume: Unknown

Issue: Unknown

Page Range: Unknown

Description:

This paper focuses on auditory sensory substitution for providing visually impaired users with suitable information in both static scene recognition and dynamic obstacle avoidance. We introduce three different sonification models together with three temporal presentation schemes, i.e. ways of temporally organizing the sonic events in order to provide suitable information. Following an overview of the motivation and challenges behind each of the solutions, we describe their implementation and an evaluation of their relative strengths and weaknesses based on a set of experiments conducted in a virtual environment.

Open Access: Yes

DOI: DOI not available

Evaluation of response times on a touch screen using stereo panned speech command auditory feedback

Hunor Nagy György Wersényi

Publication Name: Lecture Notes in Computer Science Including Subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics

Publication Date: 2016-01-01

Volume: 9811 LNCS

Issue: Unknown

Page Range: 279-286

Description:

User interfaces to access mobile and handheld devices usually incorporate touch screens. Fast user responses are in general not critical, however, some applications require fast and accurate reactions from users. Errors and response times depend on many factors such as the user’s abilities, feedback types and latencies from the device, sizes of the buttons to press, etc. We conducted an experiment with 17 subjects to test response time and accuracy to different kinds of speech-based auditory stimuli over headphones. Speech signals were spatialized based on stereo amplitude panning. Results show significantly better response times for 3 directions than for 5, as well as for native language compared to English, and more accurate judgements based on the meaning of the speech sounds rather than their direction.

Open Access: Yes

DOI: 10.1007/978-3-319-43958-7_33

A survey on hardware and software solutions for multimodal wearable assistive devices targeting the visually impaired

Aádám Csapó Myounghoon Jeon György Wersényi

Publication Name: Acta Polytechnica Hungarica

Publication Date: 2016-01-01

Volume: 13

Issue: 5

Page Range: 39-63

Description:

The market penetration of user-centric assistive devices has rapidly increased in the past decades. Growth in computational power, accessibility, and “cognitive” device capabilities have been accompanied by significant reductions in weight, size, and price, as a result of which mobile and wearable equipment are becoming part of our everyday life. In this context, a key focus of development has been on rehabilitation engineering and on developing assistive technologies targeting people with various disabilities, including hearing loss, visual impairments and others. Applications range from simple health monitoring such as sport activity trackers, through medical applications including sensory (e.g. hearing) aids and real-time monitoring of life functions, to task-oriented tools such as navigational devices for the blind. This paper provides an overview of recent trends in software and hardware-based signal processing relevant to the development of wearable assistive solutions.

Open Access: Yes

DOI: DOI not available

Sound of vision - Spatial audio output and sonification approaches

Runar Unnthorsson Michal Bujacz Alin Moldoveanu Gabriel Ivanica Aádám Csapó Simone Spagnol Charalampos Saitis Omar I. Johannesson Karol Kropidlowski Piotr Witek Mikolai Rotnicki György Wersényi

Publication Name: Lecture Notes in Computer Science Including Subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics

Publication Date: 2016-01-01

Volume: 9759

Issue: Unknown

Page Range: 202-209

Description:

The paper summarizes a number of audio-related studies conducted by the Sound of Vision consortium, which focuses on the construction of a new prototype electronic travel aid for the blind. Different solutions for spatial audio were compared by testing sound localization accuracy in a number of setups, comparing plain stereo panning with generic and individual HRTFs, as well as testing different types of stereo headphones vs custom designed quadrophonic proximaural headphones. A number of proposed sonification approaches were tested by sighted and blind volunteers for accuracy and efficiency in representing simple virtual environments.

Open Access: Yes

DOI: 10.1007/978-3-319-41267-2_28

A survey of assistive technologies and applications for blind users on mobile platforms: a review and foundation for research

Aádám Csapó Hunor Nagy György Wersényi Tony Stockman

Publication Name: Journal on Multimodal User Interfaces

Publication Date: 2015-12-01

Volume: 9

Issue: 4

Page Range: 275-286

Description:

This paper summarizes recent developments in audio and tactile feedback based assistive technologies targeting the blind community. Current technology allows applications to be efficiently distributed and run on mobile and handheld devices, even in cases where computational requirements are significant. As a result, electronic travel aids, navigational assistance modules, text-to-speech applications, as well as virtual audio displays which combine audio with haptic channels are becoming integrated into standard mobile devices. This trend, combined with the appearance of increasingly user-friendly interfaces and modes of interaction has opened a variety of new perspectives for the rehabilitation and training of users with visual impairments. The goal of this paper is to provide an overview of these developments based on recent advances in basic research and application development. Using this overview as a foundation, an agenda is outlined for future research in mobile interaction design with respect to users with special needs, as well as ultimately in relation to sensor-bridging applications in general.

Open Access: Yes

DOI: 10.1007/s12193-015-0182-7

A virtual audio environment for testing dummy-head HRTFs modeling real life situations

József Répás György Wersényi

Publication Name: Proceedings of Forum Acusticum

Publication Date: 2014-01-01

Volume: 2014-January

Issue: Unknown

Page Range: Unknown

Description:

Virtual audio simulators usually incorporate HRTF filtering and headphone playback. The most important parameters for simulation include accuracy and spatial resolution of the applied HRTFs, setting the individual parameters (customization) and further signals processing algorithms in order to equalize the headphone or tracking head movements. This paper presents a custom built MATLAB-based virtual audio environment for listening tests using various dummy-head HRTFs, ITD setting methods, headphone equalization etc. Furthermore, first results from a listening test for comparison of HRTFs recorded with a manikin wearing hair or glasses are also presented.

Open Access: Yes

DOI: DOI not available

Overview of auditory representations in human-machine interfaces

Aádám Csapó György Wersényi

Publication Name: ACM Computing Surveys

Publication Date: 2013-11-01

Volume: 46

Issue: 2

Page Range: Unknown

Description:

In recent years, a large number of research projects have focused on the use of auditory representations in a broadened scope of application scenarios. Results in such projects have shown that auditory elements can effectively complement other modalities not only in the traditional desktop computer environment but also in virtual and augmented reality, mobile platforms, and other kinds of novel computing environments. The successful use of auditory representations in this growing number of application scenarios has in turn prompted researchers to rediscover the more basic auditory representations and extend them in various directions. The goal of this article is to survey both classical auditory representations (e.g., auditory icons and earcons) and those auditory representations that have been created as extensions to earlier approaches, including speech-based sounds (e.g., spearcons and spindex representations), emotionally grounded sounds (e.g., auditory emoticons and spemoticons), and various other sound types used to provide sonifications in practical scenarios. The article concludes by outlining the latest trends in auditory interface design and providing examples of these trends.

Open Access: Yes

DOI: 10.1145/2543581.2543586

Comparison of localization performance of blind and sighted subjects on a virtual audio display and in real-life environments

József Répás György Wersényi

Publication Name: 132nd Audio Engineering Society Convention 2012

Publication Date: 2012-10-22

Volume: Unknown

Issue: Unknown

Page Range: 306-311

Description:

Localization performance of blind subjects was measured in a virtual audio environment using non-individualized but customized HRTFs. Results were compared with former results of sighted users using the same measurement setup. Furthermore, orientation and navigation tasks in a real-life outdoor environment were performed in order to compare localization ability of sighted and visually impaired including "walking straight" tasks with and without acoustic feedback and test runs using the white cane as an acoustic tool during navigation.

Open Access: Yes

DOI: DOI not available

Evaluation of vibrating sound transducers with glass membrane based on measurements and numerical simulations

György Wersényi

Publication Name: 132nd Audio Engineering Society Convention 2012

Publication Date: 2012-10-22

Volume: Unknown

Issue: Unknown

Page Range: 477-482

Description:

In recent years manufacturers introduced so-called "invisible sound" solutions. In-wall, surface mount or glass mount versions of different vibrating transducers are commercially available. The entire surface becomes a speaker delivering sound and the frequency response is said to be equivalent to conventional diaphragm speakers. Furthermore, the sound is omni directional at nearly all frequencies (60 Hz - 15 kHz) while channel separation is maintained. This paper presents measurement results of the SolidDrive SD1g transducer mounted on different glass surfaces, including vibration measurements and acoustic parameters. Furthermore, based on a numerical FEM-model using COMSOL, comparison between measured and simulated results and estimation of transfer function and directional characteristics are presented.

Open Access: Yes

DOI: DOI not available

Virtual localization by blind persons

György Wersényi

Publication Name: AES Journal of the Audio Engineering Society

Publication Date: 2012-07-01

Volume: 60

Issue: 7-8

Page Range: 568-579

Description:

Localization performance and spatial hearing abilities of blind persons are complex issues. In everyday life we rely on the "fact" that blind people can hear better, without thinking of what "better" means. Localization performance depends on many parameters such as properties of the excitation signal, environmental conditions, individual aspects, and visual influence. Our goal was to create a virtual environment aimed at helping the blind community use personal computers. In developing this environment we were concerned to cover technical and hearing related questions, as well as human factors. At first, this project included sighted subjects and basic properties of the virtual audio system and the applied HRTFs were tested. Subsequently, blind persons have been involved and comparative measurements performed using the same equipment and selected localization tasks. Twenty-eight blind person's localization performances were tested and compared with the results of 40 sighted subjects in a virtual audio environment. Blind subjects tended to be better in detecting movements in the horizontal plane around the head, localizing static frontal audio sources, and orientation in a 2-D virtual audio display. On the other hand, sighted subjects performed better identifying ascending sound sources in the vertical plane and detecting static sources in the back. In-the-head localization error rates and MAA results appeared to be about the same for both groups. The evaluation was also supported by some informal questions.

Open Access: Yes

DOI: DOI not available

Overview and comparative results of speech-based excitation signals for virtual localization and real-life applications

György Wersényi

Publication Name: 20th International Congress on Acoustics 2010 Ica 2010 Incorporating Proceedings of the 2010 Annual Conference of the Australian Acoustical Society

Publication Date: 2010-12-01

Volume: 5

Issue: Unknown

Page Range: 3885-3889

Description:

In virtual audio synthesis we use different excitation signals for listening tests. These tests are executed using headphone playback and real-time HRTF synthesis. Besides noise signals, speech is often used for tests especially for real life applications, such as mobile phones, various voice transmission lines, computer environments or accessories for the visually impaired, where speech intelligibility is important. This paper presents a summary of results of a listening test using different signals including speech in a virtual audio environment aimed at blind persons. Results show how speech contributes to the accessibility to computers and performs in a comparative test for virtual audio simulation. Furthermore, additional speech test signals are overviewed and introduced, such as speech-chorus signals, segmented spondees and the newly developed spearcons.

Open Access: Yes

DOI: DOI not available

Auditory representations of a graphical user interface for a better human-computer interaction

György Wersényi

Publication Name: Lecture Notes in Computer Science Including Subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics

Publication Date: 2010-12-01

Volume: 5954 LNCS

Issue: Unknown

Page Range: 80-102

Description:

As part of a project to improve human computer interaction mostly for blind users, a survey with 50 blind and 100 sighted users included a questionnaire about their user habits during everyday use of personal computers. Based on their answers, the most important functions and applications were selected and results of the two groups were compared. Special user habits and needs of blind users are described. The second part of the investigation included collecting of auditory representations (auditory icons, spearcons etc.), mapping with visual information and evaluation with the target groups. Furthermore, a new design method for auditory events and class was introduced, called "auditory emoticons". These use non-verbal human voice samples to represent additional emotional content. Blind and sighted users evaluated different auditory representations for the selected events, including spearcons for different languages. Auditory icons using environmental, familiar sounds as well emoticons are received very well, whilst spearcons seem to be redundant except menu navigation for blind users. © 2010 Springer-Verlag Berlin Heidelberg.

Open Access: Yes

DOI: 10.1007/978-3-642-12439-6_5

On the measurement and evaluation of bass enhanced in-ear phones

György Wersényi

Publication Name: 20th International Congress on Acoustics 2010 Ica 2010 Incorporating Proceedings of the 2010 Annual Conference of the Australian Acoustical Society

Publication Date: 2010-12-01

Volume: 4

Issue: Unknown

Page Range: 2849-2854

Description:

Measurements of the transfer function of headphones and earphones are made on dummy-heads or on ear simulators. This paper introduces measurement problems of newly designed in-ear phones, often called as micro-driver equipment. These earphones have smaller transducer diameter and are equipped with rubber or spongy material to fit in the ear canal. This coupling may create an increased sound isolation, less sound pressure and a better low frequency transmission to the eardrum. The paper presents subjective evaluation of listeners who evaluated five different kinds of in-ear phones as well as transfer function measurements using a dummy-head. Measurement problems are highlighted pointing on new aspects of a revised dummy-head standard. Copyright © (2010) by the International Congress on Acoustics.

Open Access: Yes

DOI: DOI not available

Representations of HRTFs using MATLAB: 2D and 3D plots of accurate dummy-head measurements

György Wersényi

Publication Name: 20th International Congress on Acoustics 2010 Ica 2010 Incorporating Proceedings of the 2010 Annual Conference of the Australian Acoustical Society

Publication Date: 2010-12-01

Volume: 2

Issue: Unknown

Page Range: 1058-1066

Description:

Human Head-Related Transfer Functions describe the transmission from the free-field to the eardrums. HRTFs are measured on human subjects or on dummy-heads, characterized by the angle of incidence. The dummy-head measurement method allows the acquisition of data in high spatial resolution. Our setup provided HRTF data in 1 degree horizontal and 5 degrees elevational steps in different environmental settings. Spectral evaluation in spatial hearing research requires proper representation methods of detailed measurement data. Different 2D and 3D representation methods will be presented here, using different coordinate systems, color maps and additional filtering methods programmed under MATLAB. Figures are mainly helpful for HRTF analysis but MATLAB features allow other use for applications where directional characteristics, polar plots are required. Copyright© (2010) by the International Congress on Acoustics.

Open Access: Yes

DOI: DOI not available

Effect of emulated head-tracking for reducing localization errors in virtual audio simulation

György Wersényi

Publication Name: IEEE Transactions on Audio Speech and Language Processing

Publication Date: 2009-02-01

Volume: 17

Issue: 2

Page Range: 247-252

Description:

Virtual audio simulation uses head-related transfer function (HRTF) synthesis and headphone playback to create a sound field similar to real-life environments. Localization performance is influenced by parameters such as the recording method and the spatial resolution of the HRTFs, equalization of the measurement chain as well as common headphone playback errors. The most important errors are in-the-head localization and front-back reversals. Among other cues, small movements of the head are considered to be important to avoid these phenomena. This study uses the BEACHTRON sound card and its HRTFs for emulating small head-movements by randomly moving the virtual sound source to emulate head-movements. This method does not need any additional equipment, sensors, or feedback. Fifty untrained subjects participated in the listening tests using different stimuli and presentation speed. A virtual target source was rendered in front of the listener by random movements of 1 -7 . Experiments showed that this kind of simulation can be helpful to resolve in-the-head localization, but there is no clear benefit for resolving front-back errors. Emulation of small head-movements of 2 could actually increase externalization rates in about 21% of the subjects while presentation speed is not significant. © 2009 IEEE.

Open Access: Yes

DOI: 10.1109/TASL.2008.2006720

Localization in a Head-Related Transfer Function-based virtual audio synthesis using additional high-pass and low-pass filtering of sound sources

György Wersényi

Publication Name: Acoustical Science and Technology

Publication Date: 2007-08-02

Volume: 28

Issue: 4

Page Range: 244-250

Description:

Listening tests were carried out for investigating the localization judgments of untrained subjects through equalized headphones and with HRTF synthesis. The investigation was made on the basis of the former 'Graphical User Interface for Blind Persons' project in order to determine the possibilities of a 2D virtual sound screen and headphone playback. 50 untrained subjects evaluated a virtual audio display in front of the listener using different horizontal and vertical resolutions on a 2D surface. A listening test using white and filtered noise signals was followed by a special investigation using simple high-pass and low-pass filtering of the original sound in order to increase correct vertical localization judgments. The simulation uses high-pass filtering for higher elevations and low-pass filtering for lower elevations in a 5 × 2 and a 3 × 3 spatial resolution. Results of the listening test will be presented and the efficiency of the filtering in correct localization judgments will be discussed. © 2007 The Acoustical Society of Japan.

Open Access: Yes

DOI: 10.1250/ast.28.244

Evaluation of dummy-head HRTFs in the horizontal plane based on the peak-valley structure in one-degree spatial resolution

György Wersényi

Publication Name: Institute of Noise Control Engineering of the Usa 35th International Congress and Exposition on Noise Control Engineering Inter Noise 2006

Publication Date: 2006-12-01

Volume: 7

Issue: Unknown

Page Range: 4487-4495

Description:

Dummy-heads are often used for standardized measurements where modeling of the human head and torso is relevant. Monaural Head-Related Transfer Functions of a Brüel & Kjaer dummy were measured in the horizontal plane in one-degree spatial resolution. Evaluation is made by plotting the peak-valley structure in frequency. Special frequency and spatial domains can be determined based on the variations of the HRTFs that are relevant to understand physical properties of the dummy -head in measurements and processes of human directional hearing. Symmetries and similarities of measured HRTFs help to scrutinize the perception of directional information in the monaural and binaural evaluation, the "noisy domain" in frequency and space where shadowing of the head occur as well as the filtering effect of the pinna.

Open Access: Yes

DOI: DOI not available

Spatial and spectral properties of the dummy-head during measurements in the head-shadow area based on HRTF evaluation

György Wersényi

Publication Name: Institute of Noise Control Engineering of the Usa 35th International Congress and Exposition on Noise Control Engineering Inter Noise 2006

Publication Date: 2006-12-01

Volume: 7

Issue: Unknown

Page Range: 4477-4486

Description:

In accurate and repeatable measurements dummy -heads are often used to model the average human head and body. They are suited for standardized measurements and for investigating the human spatial hearing and localization performance. The monaural Head-Related Transfer Functions (HRTFs) of the dummy-head can be used for various investigations. This paper uses the HRTF-set of a Brüel & Kjaer head and torso simulator focusing on the so called monaural head-shadow area, where one of the ears is shadowed by the head itself. Based on long-term measurements using the bare torso as well as other accessories (glasses, clothing etc.) on it, the extent of the head-shadow area will be presented in frequency and space. The head-shadow area is investigated in connection with the overall SNR of the measurement and sensitivity domains of the ears. Conclusions are drawn for binaural recognition in human spatial hearing using low-frequency 'bright spots' and high-frequency information during lateral-contralateral evaluation.

Open Access: Yes

DOI: DOI not available

Environmental influence on the fine structure of dummy-head HRTFs

András Illényi György Wersényi

Publication Name: Forum Acusticum Budapest 2005 4th European Congress on Acustics

Publication Date: 2005-12-01

Volume: Unknown

Issue: Unknown

Page Range: 2529-2534

Description:

The directional filtering of the outer ears is a significant step during the evaluation of spatial information. A computer-controlled dummy-head measurement system was developed to measure the HRTFs in huge amount and with increased spatial resolution. Effects and common properties of objects near the head (glasses, hair, baseball cap) were measured. Changes in the HRTFs due to the acoustical environment will be presented as function of frequency and azimuth for different elevations on 2D polar diagrams. Differences of about 1 dB are evaluated in the fine structure of the measured HRTFs and conclusions are drawn for the relevance of HRTF reproduction in binaural synthesis.

Open Access: Yes

DOI: DOI not available

Evaluation of HRTF data using the head-Related Transfer Function Differences

András Illényi György Wersényi

Publication Name: Forum Acusticum Budapest 2005 4th European Congress on Acustics

Publication Date: 2005-12-01

Volume: Unknown

Issue: Unknown

Page Range: 2475-2479

Description:

A simple spectral computation method is introduced for the evaluation of differences in dummy-head Head-Related Transfer Functions (HRTFs). These transfer functions describe the directional-dependent filtering of the outer ears and are responsible for basic localization cues. Head-Related Transfer Function Differences (HRTFDs) are defined as the quotient of measured HRTFs in the same direction, comparing the cases of modified environmental conditions. The HRTFDs are relative measures and thus free from systematic errors of the measurement system and individual parameters. Our experience shows that HRTFDs are well suited to analyze the fine structure of measured HRTF data and for representation of the changes in the acoustical environment near or on the head. HRTFDs of a BK dummy-head will be shown representing differences from about 1 dB. This measurement accuracy was determined by replacing the dummy-head with an omnidirectional microphone.

Open Access: Yes

DOI: DOI not available

A Cost-Effective Hardware and Software Solution for Telerehabilitation in Homecare

József Tollár Balazs Lukacs György Wersényi

Publication Name: 2024 IEEE International Conference on Microwaves Communications Antennas Biomedical Engineering and Electronic Systems Comcas 2024

Publication Date: 2024-01-01

Volume: Unknown

Issue: Unknown

Page Range: Unknown

Description:

In telerehabilitation., services are provided from a distance using telecommunication technologies. With the proliferation of broadband internet services and wireless networks., high-speed and low-latency data transmission can be maintained that allows for high quality audio and video communication. However., offline solutions without outsourcing of the computational need into the cloud are still required. Homecare solutions offer possibilities for rehabilitation of patients in their home environment. Guided workouts and training sessions can be automated and controlled with the help of cost-effective hardware and software applications. This paper presents first results of a latest development in homecare telerehabilitation with automated recognition of motion, evaluation and feedback.

Open Access: Yes

DOI: 10.1109/COMCAS58210.2024.10666254

Musings on the Metaverse and on how the Internet of Digital Reality Encompasses Future Developments of the Internet

György Wersényi

Publication Name: Infocommunications Journal

Publication Date: 2023-01-01

Volume: 2023

Issue: Unknown

Page Range: 21-28

Description:

Internet of Digital Reality (IoD) is a concept that encompasses various aspects of the next level of communication between digital cognitive entities. Extending the concept of IoT and IoE, IoD includes all kinds of entities interacting in virtual reality, focusing not only on the technology, physical and logical networks, but also on cognitive aspects and human factors. The Metaverse – as a key element of IoD – was introduced and has lately been re-vitalized as a kind of vision for the future of the Internet, especially focusing on social media, where users interact via their avatars in a fully immersive VR scenario. In this paper, I nevertheless argue that IoD is more than a “VR Facebook”, and that although the Metaverse can offer a new kind of experience, it isn’t free from drawbacks and valid criticisms.

Open Access: Yes

DOI: 10.36244/ICJ.2023.SI-IODCR.4