Virtual Location Research Articles

An extrapolation-based virtual sensing technique of improving the control performance of the FxLMS algorithm in a maritime environment

Several local active noise control (ANC) approaches based on Filtered-x Least Mean Square (FxLMS) algorithm have been designed to mitigate low frequency noise annoyance from undesirable acoustic sources, for which conventional passive techniques are ineffective. A fundamental limitation of local ANC is the small size of quiet zone that is extended around the error microphone. This means that the physical sensor should be mounted at the desired location of noise attenuation, which in most cases is practically inconvenient. In order to extend the zone of quiet close to the ears of a seated passenger who moves gently his head, a number of complicated and computationally heavy virtual sensing algorithms have been developed for ANC. The spatial performance of such a local active sound controller depends not only on the correlation properties of the primary sound field and the adaptation algorithm but also on the microphones spatial arrangement, the size and the number of the control sources. Thus, the objective of this work is to develop a simple, robust and computationally-efficient virtual sensing ANC algorithm of improving the performance of the conventional FxLMS. The main approach to do so is by using a feedforward ANC controller based on the combined solution of first-order pressure prediction technique and a mixed-error design integrating the FXLMS algorithm for enhancing the noise attenuation levels and shaping an extended silence zone. Aim of this work is also to estimate a simplified approach of the virtual secondary path in order to be more challenging in practical and commercial applications, while the ANC system can achieve adequate control performance.In an effort to test the extension degree of the silence zone generated at a fixed virtual location, low computational demand ANC headrest configurations, are investigated. The proposed schemes have been tested through a simulation model, a test rig and an experimental ANC system installed in a cabin mock-up. The computer-modeled and the experimental results demonstrate that the proposed local virtual sensing ANC algorithm maintains stability in all operating points, and works reliably and more effectively than the widely used conventional FxLMS algorithm.

Dimensions of Online Role-Playing: Anchored in the Tolkien Mythos

Based on close study of two multi-player games in the tradition of J. R. R. Tolkien, this study documents the complex features of modern role-playing in online virtual worlds and constructs a six-component typology of its dimensions. The Lord of the Rings: War in the North is oriented toward the popular movies based on Tolkien’s novels, and can be played by as many as three people. The Lord of the Rings Online is based directly on the novels and is massively multi-player, even one event reported here having 487 avatars simultaneously at the same virtual location. A brief sociometric analysis of thousands of online stories in Tolkien’s legendarium, observation inside 20 Tolkien Facebook groups, and references to social science published during Tolkien’s lifetime, anchor the analysis in a tradition. The six theory components interact dynamically: identity, function, connection, engagement, representation, and property. They were derived from participant observation and ethnographic methods, but also illustrated by statistics, notably censuses of avatars and their homesteads. A great number of other role-playing computer games have similar components, but often fewer and less clearly represented. Therefore, this pair in the Tolkien mythos were especially suitable for this concept-development project.

Influence of Seismic Loads Considering Soil Properties and Wave Passage Effect on the Seismic Response of a Multi-Span PSC Girder Bridge

This paper investigates the analytical results of the seismic response of multi-span prestressed concrete (PSC) I-girder bridges under seismic loads. To perform numerical analyses, a three-span PSC I-girder bridge with a width of 12 m, a total length of 100 m, and a maximum span length of 40 m was modeled, and a virtual location was selected to consider the soil properties of the area where the bridge was constructed. The seismic load acting on the PSC I-girder bridge was applied in consideration of the soil properties around the pier and the wave passage effect of the bedrock in the artificial seismic load generated, according to the U.S. Nuclear Regulatory Commission (NRC) standard. The analysis results confirmed that the seismic load, with consideration of the soil properties and wave passage effect, generated the maximum response acceleration and bending moment at the deck of the bridge—152% and 232% greater than without considering them, respectively. Therefore, in order to ensure the earthquake resistance of the bridge, the soil properties of the area where the bridge will be built and the wave passage effect of the bedrock must be considered.

A novel upper-limb tracking system in a virtual environment for stroke rehabilitation

BackgroundThe transfer of the behaviors of a human’s upper limbs to an avatar is widely used in the field of virtual reality rehabilitation. To perform the transfer, movement tracking technology is required. Traditionally, wearable tracking devices are used for tracking; however, these devices are expensive and cumbersome. Recently, non-wearable upper-limb tracking solutions have been proposed, which are less expensive and more comfortable. However, most products cannot track the upper limbs, including the arms and all the fingers at the same time, which limits the limb parts for tracking in a virtual environment and may lead to a limited rehabilitation effect.MethodsIn this paper, a novel virtual reality rehabilitation system (VRRS) was developed for upper-limb rehabilitation. The VRRS could track the motion of both upper limbs, integrate fine finger motion and the range of motion of the entire arm and map the motion to an avatar. To test the performance of VRRS, two experiments were designed. In the first experiment, we investigated the effect of VRRS on virtual body ownership, agency and location of the body and usability in 8 healthy participants by comparing it with a partial upper-limb tracking method based on a Leap Motion controller (LP) in the same virtual environments. In the second experiment, we examined the feasibility of VRRS in upper-limb rehabilitation with 27 stroke patients.ResultsVRRS improved the users’ senses of body ownership, agency, and location of the body. The users preferred using the VRRS to using the LP. In addition, we found that although the upper limb motor function of patients from all groups was improved, the difference between the FM scores tested on the first day and the last day of the experimental group was more significant than that of the control groups.ConclusionsA VRRS with motion tracking of the upper limbs and avatar control including the arms and all the fingers was developed. It resulted in an improved user experience of embodiment and effectively improved the effects of upper limb rehabilitation in stroke patients.Trial registrationThe study was registered at the First Affiliated Hospital of Jinan University Identifier: KY-2020–036; Date of registration: June 01, 2020.

Place attachment satisfies psychological needs in the context of environmental risk coping: Experimental evidence of a link between self-determination theory and person-place relationship effects

The present paper aims to provide some empirical evidence of how the ability of places to satisfy psychological needs might be an antecedent for the creation of an affective bond with those places by using visualization techniques for place attachment manipulation and exploring the similarities between two main frames of reference in literature, place attachment literature and Self-Determination Theory (SDT). The paper has three main hypotheses: 1) showing that the basic needs hypothesized by SDTand those hypothesized by Place Attachment Literature are both affected by place features and have similar affective and behavioral outcomes; 2) showing that the ability of a place to satisfy individual's needs is associated with the individual attachment to the place; 3) showing that the place attachment developed by the perception of needs satisfaction affects individual's place-related behaviors.Two experimental studies were conducted manipulating place attachment toward a new evacuation site in a virtual location affected by natural hazards, with two scenario manipulations. One manipulation is realized on the basis of the needs emerged by place attachment literature taxonomies. The second manipulation aims to the same target on the basis of Self-Determination Theory. Study 1 shows that both manipulations affect psychological need satisfaction and place attachment; Study 2 shows that they also affect risk coping place-related behavior. Results confirm the three hypotheses and shed light on how psychological needs satisfaction is linked to place attachment and its practical relevance for environmental risk perception and coping in natural hazard contexts, possibly improving risk coping plans in emergency situations and, ultimately, saving lives. Moreover, these results could be applied also to other settings, like shelters or temporary settlements improving wellness conditions in these environments.

PREFACE OF ICROEST 2021

The Third International Conference of Interdisciplinary Research on Green Environment Approach for Sustainable Development (ICROEST) 2021 was held Virtual location organized in Makassar, Indonesia on June 4-5, 2021. ICROEST 2021 is dedicated to address issues related to Green Environment Approach for Sustainable Development hosted by Publication Management Center (PMC) Universitas Hasanuddin. The conference is still being held virtually, because the death rate due to Covid-19 in Indonesia is still high and there are also government policies on social restrictions.The implementation of the conference technically utilizes all types of social media that are used before and during the event. At the peak of implementation, this conferene used a zoom account belonging to the university with a capacity of 1000 participants. Although it was held virtually, the entire committee gathered at the PMC Universitas Hasanuddin for the smoothness of this conference.Relies on the fact that, sustainable development has become a serious issue for the last decades since the earth is getting old and the availability of resources is shrinking. As being part of well beings and to take part in earth saving, ICROEST 2021 as a space for sharing knowledge, experience, and research as well as for discussing and finding solutions in the development of earth in more environmentally friendly ways. The conference is bringing a theme: environmental improvement and sustainable development. It gathers researches and stakeholders especially in the field of (1) Animal Production and Sustainable Agriculture; 2) Environment Risk Assessment; 3) Biodiversity; 4) Green Engineering; 5) Biotechnology; 6) Green agriculture; 7) Natural resource.List of Conference Committee & Reviewer ICROEST 2021 are available in this pdf.

For 19-Month-Olds, What Happens On-Screen Stays On-Screen.

Humans rely extensively on external representations such as drawings, maps, and animations. While animations are widely used in infancy research, little is known about how infants interpret them. In this study, we asked whether 19-month-olds take what they see on a screen to be happening here and now, or whether they think that on-screen events are decoupled from the immediate environment. In Experiments 1–3, we found that infants did not expect a falling animated ball to end up in boxes below the screen, even though they could track the ball (i) when the ball was real or (ii) when the boxes were also part of the animation. In Experiment 4, we tested whether infants think of screens as spatially bounded physical containers that do not allow objects to pass through. When two location cues were pitted against each other, infants individuated the protagonist of an animation by its virtual location (the animation to which it belonged), not by its physical location (the screen on which the animation was presented). Thus, 19-month-olds reject animation-reality crossovers but accept the depiction of the same animated environment on multiple screens. These results are consistent with the possibility that 19-month-olds interpret animations as external representations.

Implementation of robust virtual sensing algorithm in active noise control to improve silence zone

Active noise control (ANC) is a successful technique to reduce unwanted noise based on the superposition principle. In a conventional ANC system, the extent of unwanted noise can be attenuated at the error microphone location, thus making a silent zone at the desired location. However, in certain situations, it is impossible to place the error microphone at the desired location. In that case, the error microphone cannot assure adequate noise suppression at the desired location. To overcome that, the virtual sensing technique (VST) has been implemented in ANC to shift the zone of silence to the desired position. This paper proposes a supplemental filter in VST to avoid interference issues between secondary and virtual paths..In the virtual ANC, the supplemental filter H provides the required information to measure optimal noise control filter and also increases noise reduction in the ANC system at the virtual location. A Real-Time Simulink model is designed for the proposed virtual sensing ANC and evaluate its efficiency. The computer simulation findings showed that the ANC system performance with the proposed virtual sensing method had good noise reduction at the virtual location compared to the physical location. The proposed supplemental filter preserves reasonable noise reduction efficiency in the ANC system if the physical microphone is positioned far from the location of the silence zone.

Biometric recognition using wearable devices in real-life settings

The popularity of wearable devices, such as smart glasses, chestbands, and wristbands, is nowadays rapidly growing, thanks to the fact that they can be used to track physical activity and monitor users’ health. Recently, researchers have proposed to exploit their capability to collect physiological signals for enabling automatic user recognition. Wearable devices inherently provide the means for detecting their unauthorized usage, or for being used as front-end in biometric recognition systems controlling the access to either physical or virtual locations and services. The present work evaluates the feasibility of performing biometric recognition using signals captured by wearable devices, considering data collected through off-the-shelf commercial wristbands, and comparing recordings taken during two distinct sessions separated by an average time of 7 days. In more detail, recognition is performed leveraging on electrodermal activity (EDA) and blood volume pulse (BVP), considering measurements taken from 17 subjects performing natural activities such as attending or teaching lectures. Several tests have been carried out to determine the most effective representation of the considered EDA and BVP signals, as well as the most suitable classifier. The best recognition performance has been achieved exploiting convolutional neural networks to extract discriminative characteristics from the combined spectrograms of the employed EDA and BVP data, guaranteeing average correct identification rate of 98.58% for test samples lasting 30 seconds.

Electromagnetic surgical navigation in patients undergoing mandibular surgery

The purpose of this study was to evaluate the feasibility of electromagnetic (EM) navigation for guidance on osteotomies in patients undergoing oncologic mandibular surgery. Preoperatively, a 3D rendered model of the mandible was constructed from diagnostic computed tomography (CT) images. Cutting guides and patient specific reconstruction plates were designed and printed for intraoperative use. Intraoperative patient registration was performed using a cone beam CT scan (CBCT). The location of the mandible was tracked with an EM sensor fixated to the mandible. The real-time location of both the mandible and a pointer were displayed on the navigation system. Accuracy measurements were performed by pinpointing four anatomical landmarks and four landmarks on the cutting guide using the pointer on the patient and comparing these locations to the corresponding locations on the CBCT. Differences between actual and virtual locations were expressed as target registration error (TRE). The procedure was performed in eleven patients. TREs were 3.2 ± 1.1 mm and 2.6 ± 1.5 mm using anatomical landmarks and landmarks on the cutting guide, respectively. The navigation procedure added on average half an hour to the duration of the surgery. This is the first study that reports on the accuracy of EM navigation in patients undergoing mandibular surgery.

Generation of a long-term daily gridded precipitation dataset for the Upper Indus Basin (UIB) through temporal Reconstruction, Correction & Informed Regionalization-“ReCIR”

This study attempted to generate a long-term (1961–2010) daily gridded precipitation dataset for the Upper Indus Basin (UIB) with orographic adjustments so as to generate realistic precipitation estimates, enabling hydrological and water resource investigations that can close the water balance, that is difficult, if not impossible to achieve with the currently available precipitation data products for the basin. The procedure includes temporal reconstruction of precipitation series at points where data were not recorded prior to the mid-nineties, followed by a regionalization of the precipitation series to a smaller scale across the basin (0.125 ° × 0.125 °), while introducing adjustments for the orographic effect and changes in glacier storage. The reconstruction process involves interpolation of the precipitation at virtual locations of the current (1995-) dense observational network, followed by corrections for frequency and intensity and adjustments for temporal trends at these virtual locations. The data generated in this way were further validated for temporal and spatial representativeness through evaluation of SWAT-modelled streamflow responses against observed flows across the UIB. The results show that the calibrated SWAT-simulated daily discharge at the basin outlet as well as at different sub-basin outlets, when forcing the model with the reconstructed precipitation of years 1973–1996, is almost identical to that when forcing it with the reference precipitation data (1997–2008). Finally, the spatial distribution pattern of the reconstructed (1961–1996) and reference (1997–2008) precipitation were also found consistent across the UIB, reflecting well the large-scale atmospheric-circulation pattern in the region.

RETRACTED: Virtual reality sports auxiliary training system based on embedded system and computer technology

Virtual Reality technology, the complex environment can be a simulated, traditional sports courses at the stadium, equipment, it is due to limitations such as safety, to provide scientific and accurate teaching and learning's, a complex by visualizing the theoretical knowledge in the abstract sport, you can get more technical knowledge. Compared to the traditional physical education activities, simulate sports scene only by generating VR panoramas that cannot be virtual reality technology. Based on this, you can improve the enthusiasm and athletic ability of students effectively. Because of immaturity and high-priced equipment of VR technology, at present, people that education is using unpopular making, carefully virtual reality technology. In this context, we can apply virtual reality technology to sports training, which can obtain more effective training effect. In the first part of this paper, we talk about the research of virtual reality panorama, the second part about the research of virtual reality video, the third part about the application of virtual reality in physical education teaching, and the fourth part is the conclusion and investigation process. In the study, VR, as a new technology, found that you have the prospect of a wide range of applications. As long as it has been used in scientific and rational, you can VR is to promote the level of improvement and sports greatly sports scene. Users can increase users' interest; it can be immersed in a variety of preset virtual locations. Therefore, in the VR device, which allows the user to improve the experience of the VR device, you can interact well in a virtual scene.

Robust Q-Gradient Subband Adaptive Filter for Nonlinear Active Noise Control

Active noise control (ANC) is gaining attention for attenuating noise from a remote location. Considering the problem of nonlinear active noise control (NLANC) at a virtual location, a robust filtered-s subband adaptive filtering algorithm based on the $q$ -gradient maximum correntropy criterion (RFsSAF-qMCC) is proposed in this paper. The proposed RFsSAF-qMCC algorithm develops the functional link artificial neural network (FLANN)-SAF structure as the controller, and embeds the MCC with the concept of q -gradient, thereby improving the convergence speed in the impulsive environment. To solve the trade-off between fast convergence and low noise residue caused by the fixed q -gradient, a variable q -gradient algorithm, termed as RFsSAF-vqMCC, is further developed. As an additional contribution, the convergence behavior of the proposed RFsSAF-qMCC and RFsSAF-vqMCC algorithms is analyzed. Simulation results corroborate the effectiveness of the proposed algorithms as compared to state-of-the-art algorithms.

Sparse Array Design for DOA Estimation of Non‐Gaussian Signals: From Global Postage‐Stamp Problem Perspective

In this paper, a sparse array design problem for non‐Gaussian signal direction of arrival (DOA) estimation is investigated. Compared with conventional second‐order cumulant‐ (SOC‐) based methods, fourth‐order cumulant‐ (FOC‐) based methods achieve improved DOA estimation performance by utilizing all information from received non‐Gaussian sources. Considering the virtual sensor location of vectorized FOC‐based methods can be calculated from the second order difference coarray of sum coarray (2‐DCSC) of physical sensors, it is important to devise a sparse array design principle to obtain extended degree of freedom (DOF). Based on the properties of unfolded coprime linear array (UCLA), we formulate the sparse array design problem as a global postage‐stamp problem (GPSP) and then present an array design method from GPSP perspective. Specifically, for vectorized FOC‐based methods, we divide the process of obtaining physical sensor location into two steps; the first step is to obtain the two consecutive second order sum coarrays (2‐SC), which can be modeled as GPSP, and the solutions to GPSP can also be utilized to determine the physical sensor location sets without interelement spacing coefficients. The second step is to adjust the physical sensor sets by multiplying the appropriate coprime coefficients, which is determined by the structure of UCLA. In addition, the 2‐DCSC can be calculated from physical sensors directly, and the properties of UCLA are given to confirm the degree of freedom (DOF) of the proposed geometry. Simulation results validate the effectiveness and superiority of the proposed array geometry.

Planning an experiment in a virtual environment reality as a place of research on human behaviour using methods of neuroscience measurement – bibliometric analysis and methodological approach

The methods used in cognitive neuroscience allow through measurement methods to analyze the behavior of subjects. In the opinion of the authors, the application of the experiment in a virtual environment and the measurement of brain activity can obtain a detailed analysis of the information and knowledge of the subject. For this to happen, however, it is important that the entire course of the study is carried out in accordance with the assumptions, without errors that could affect the incorrect interpretation of the results obtained. Planning an experiment focuses on planning all the details involved in carrying out the study (Hicks, 1973, Goodwin, 2008). Therefore, in the course of the research, the authors sought information on the methodology of experimental research carried out in a virtual reality environment with the use of selected tools of cognitive neuroscience, including in particular the use of virtual reality (VR), electroencephalograph (EEG) and eye tracking. Valuable knowledge and information on this topic can be found, among others, in the publication of B Rey, M Alcañiz in the article "Research in neuroscience and virtual reality" [1] in which the importance of the implementation of research in virtual reality is highlighted. The authors believe that VR is an ideal tool to "generate controlled environments the can be used to observe human behavior. Different aspects can be analyzed from a neuroscience perspective, including perception, control of movement, learning, memory, and emotional aspects. " However, in order to assess the extent to which the experimental method in combination with technology allows for reliable information and knowledge management, it was necessary to look at considerations of the research methodology. Therefore, as the first stage, a bibliometric study was adopted, the analysis of the content contained in three databases such as WoS, Scopus, and Google Scholar. The analyses carried out showed a small percentage of publications presenting the methodology of implementation of an experimental study in VR treated as an environment in which research is carried out, within which the aforementioned methods of measurement from the field of neuroscience were applied. Based on the analysis, the authors, on the basis of selected materials in which the research processes have been well-grounded in methodology, as well as on their own research experience, will present the stages of design and implementation of an experimental study carried out in the virtual reality environment using the indicated methods of cognitive neuroscience. Based on a case study, they presented the activities carried out in the course of analyzed events, as well as pointed to potential errors that may occur in the course of research. A supermarket was taken as the virtual location of the study.

Effects of Additive Noise in Binaural Rendering of Spherical Microphone Array Signals

Additive noise produced by the recording hardware will contribute to streamed signals from spherical microphone arrays under practical conditions. For the application of binaural reproduction and under the assumption that the noise is uncorrelated between the array channels, the spectral properties and the overall level of the rendered noise in the ear signals have been shown to be strongly influenced by the configuration of the array as well as of the processing pipeline. In a previous investigation, we determined the audibility thresholds for changes in the rendered noise due to listener head rotations as a function of the differences in noise level of individual array channels. In this article, we calibrate the instrumental metric of Composite Loudness Level to the perceptual data and predict audibility of changes in the additive noise due to head rotations for a broad set of array configurations and distributions of the noise levels across array channels. We demonstrate that some types of microphone layouts can produce audible variations even if the noise level is equal in all channels. This is particularly the case for sampling grids that exhibit negative quadrature weights such as the Lebedev and Fliege-Maier grids for some spherical harmonic orders. The analysis of configurations with unevenly distributed noise contributions show that the influence of the noise from individual array channels is determined by the proximity of their virtual location to the relative trajectory of the ears.

A new grid partitioning technology for location privacy protection

Nowadays, the location-based service (LBS) has become an essential part of convenient service in people's daily life. However, the untrusted LBS servers can store lots of information about the user, such as the user's identity, location, and destination. Then the information can be used as background knowledge and combined with the query frequency of the user to launch the inference attack to obtain user's privacy. In most of the existing schemes, the author considers the algorithm of virtual location selection from the historical location of the user. However, the LBS server can infer the user's location information on the historical data that has been counted for a long time. In order to ensure that the users? historical query data and query frequency will not be obtained by the attacker, we propose a privacy protection algorithm based on grid expansion. With the help of third-party agents, the combination of cooperative users and pseudonyms can resist the privacy disclosure caused by users requesting services during the mobile process. Extensive simulation experiments have been carried out on Gowalla dataset to evaluate the efficiency of the proposed algorithm. By comparing with other existing methods, the experimental verify the effectiveness of our algorithm in privacy protection.

Social Interaction and Pain Threshold in Virtual Reality.

This experiment examined the effects of social presence and perceived location of a virtual environment on participants' pain thresholds in a preregistered, within-subjects experiment. First, we examined the effects of social interaction versus being alone in a virtual environment. Second, we compared a virtual environment representing a remote location to a replication of the laboratory environment. Social interaction predicted increased pain tolerance, but there was no effect of the "location" of the virtual environment. To our knowledge, this research project is the first to use real-time social interaction in virtual reality as a distractor for experimental thermal pain, and the first to examine the potential interaction between social interaction and transportation to different virtual locations. While this task is not directly analogous to the experience of pain in a medical setting, this preliminary study indicates future avenues for patient treatment. Clinical Trial Registration number: 1701006910.

The effects of transition style for collaborative view sharing in immersive Virtual Reality

New low-cost Virtual Reality (VR) technology is enabling large numbers of engineers and designers to be outfitted with VR tools. This, in turn, is making feasible new tools such as immersive, collaborative, design environments that reflect the collaborative environment of drafting tables while still providing all the power of modern, computer-based, design tools. However, before such an environment can be fully realized, basic issues surrounding collaboration in VR such as cybersickness and disorientation must be more fully addressed. This work presents the results of an experimental study conducted to characterize the trade-offs between different styles of transitioning collaborators to a shared view in an immersive virtual environment. The experimental task consisted of asking participants to identify in which quadrant of the car specific components were located. Quadrant identification was performed after a participant’s virtual location was transitioned to a shared view location focused on the component to identify. The study was conducted with 45 participants who provided 1890 transition response datapoints. Analysis of these results suggests that, in many cases, collaborators are willing to experience some mild cybersickness in order to reduce their disorientation and improve both confidence and accuracy of component location identification. The results also support the recommendation that the best practice is to provide support for multiple transition styles and allow collaborators to select their preference.

Data Integrity and Recovery Management Under Peer to Peer Convoluted Fault Recognition Cloud Systems

Data is expanding beyond the speed of light and hence a lighting speed devices and networks are required for a better and more reliable system for data storage. Cloud computing is a boon for larger, remote data storage at a virtual location. Cloud computing encounters major challenges such as security, connectivity and backup recovery. In this paper, a novel methodology is proposed and concentrated on backup and recovery management to provide a fault tolerance and recognition cloud system with a higher order of reliability and scalability. The methodology proposes an approach of data segmentation and token generation for data split-up using tailing terminology of appending cloud storage location or addresses. Thus the faulty cloud server missing a location segment is recognized within a smaller broadcasting limit and fetches backup from secure neighboring sources.