Search

As we roam further into the future, digitization becomes an essential tool in thinning the barrier between the physical and cyber worlds. We grow expectations of bringing more and more of the world at our fingertips, and eventually being able to access data or experiences by the means of easily operable electronic devices. Reviving the libraries use, especially in academic context, by augmenting their spaces through Augmented Reality techniques or mirroring their spaces in Virtual Reality, eases the training of the readers in knowing and using the library, and provides a solid foundation for plenty of new collaborative experiences for readers and visitors. Additionally, the 3D reconstruction of libraries, needed for Virtual Reality, provides an opportunity to disseminate online such rich cultural spaces, and preserve their patrimonial value. This paper presents the case study of 3D reconstructing the University Central Library of Bucharest. First, we briefly present related work. Then, we analyse various reconstruction techniques. Latest hardware and software advances open a wide range of new reconstruction methods, each having advantages, costs and limitations. We discuss both automatic and manual reconstruction, and combinations of both. Next, we identify and analyse the problems to be solved for our reconstruction subject and pinpoint solutions offering fidelity, rapid reconstruction, moderate use of resources, and sufficient performance for real-time applications (including VR). Finally, we detail, through practical examples, the solutions or optimal techniques, depending on the characteristics of the part to be modelled. Together, they all form an efficient hybrid solution satisfying our objectives. [ABSTRACT FROM AUTHOR]

The purpose of the SAFE-VR (System for Ameliorating Phobias based on Exposure to Virtual Reality) project is to design and implement a feasible system for treating phobias based on gradual exposure in the Virtual Reality (VR), accompanied by physiological signals monitoring (pulse, electrodermal activity and electroencephalogram (EEG) data), real-time visual feedback and automatic adaptation of the virtual environment (visual stimuli rendered via a Head Mounted Display (HMD) device and 3D audio stimuli) based on the biophysical data recorded from the user. SAFE-VR represents a substantial evolution compared to the actual systems for treating phobias and an economical approach with high perspectives, as it can be used both in the presence of a therapist under clinical surveillance and independently, for home training, on the computer and on Android devices. Exposure to Virtual Reality has the following advantages: immersion, greater diversity of environments, visual and auditory stimuli that are easily controllable by the therapist, safer environment, accessibility and flexibility in adapting the virtual world to the user's needs and preferences. Monitoring the physiological signals will add the advantages of behavioural-cognitive therapy, by assuming user's reactions and controlling them. In this way, the patient can understand his attitude towards the object that produces fear and work on dealing with it. The user is required to play a game with quests and tasks of various difficulties. For this, we have designed two realistic scenes rendered through a Head Mounted Display (a HTC Vive device) - a mountain landscape with cliffs, highlands and slopes during summer and winter time. This paper presents the development and design of the game and the structure of scenes. [ABSTRACT FROM AUTHOR]

Society has been very quick to adopt and master computer, as well as latest mobile technologies as an integral part of its everyday life. Innovative technologies have penetrated into nearly every aspect of human life and are now so much involved and embedded in social life that most people do not even realize that these technologies are relatively new inventions. Furthermore, nowadays people do not imagine their daily life without technology. In fact, information technologies create great comforts for humans in their everyday life. Despite that, one cannot say for sure that technology has only positive impact on physical, mental or psychological state of humans. Now we are living in the era of digital technologies, where scientists put forward a hypothesis according to which such deep penetration of technologies into human life might have dangerous consequences. If we look around for a moment we will notice that it is almost impossible to imagine social life and life as a whole without state-of-the-art technologies and application thereof. The given research has as its objective to study and display health related aspects, the influence (whether positive or negative) of innovative technologies on human health and to compare the results with those of the past when human life was not exposed to technological influence, as well as reveal the impact of technology, in general, on human health. There are different types of technologies and we cannot cover all impacts of all technologies in all activities. I.e., as a result of comparison between the differences of the current and recently used education methods it becomes obvious that technological development has brought to the constant increase of the time spent in a sitting position which causes some health issues in the future. Due to the modern technologies it becomes possible to get an on-line education this way minimizing the human movement. [ABSTRACT FROM AUTHOR]

Out of the many uses of eLearning - one that stands out for having a potentially great impact on the quality of life of its users - is relearning physical and psychical abilities that were lost after acute illnesses or injuries through rehabilitation processes. Such disabilities are a great burden on the patient, on his caregivers, and on society. Simple everyday tasks represent a challenge and the patient must learn again gestures that seemed habitual before the accident. Amongst the various sciences and technologies that have been used in order to improve the classical rehabilitation processes, Virtual Reality seems to be one of the most promising. Virtual Reality is an emerging science in the field of rehabilitation, that is gaining more and more uses, due to its great advantages, such as stimulating movement and cerebral activity, increasing attention levels and simulation various environments that enhance the rehabilitation sessions. The fact that VR technologies are not yet used on a large scale in rehabilitation is due to certain disadvantages that are limiting its adoption in every specialized clinic or rehabilitation centre. Despite its many benefits, Virtual Reality in rehabilitation also has notable disadvantages that result from it using state of the art technology such as: cost-related issues, issues generated by the human-computer interfaces that it uses, which may seem unnatural for first time users, immersion issues may influence the quality of the rehabilitation process, and also compatibility issues between various devices may arise. Virtual Reality systems usually process large amounts of data, thus need processing and storage capacity. Also, many VR systems users reported side effects that cannot be ignored, as they may have an impact on the quality of the rehabilitation process but may also bring legal and ethical issues. In order to be widely adopted, VR rehabilitation must bring an obvious and secure improvement to the patient, creating an attractive price/benefit ratio. Also, the expectations of the patient must be aligned to the possibilities that the technology offers and the practitioners must be tutored in using such systems in order to obtain the most benefits. In this article we will review the most important disadvantages as well as analyze possible solutions for overcoming them. The solutions may be available at the present moment, or may require that the technology progresses, but the key factor seems to be cost related, as lowering the costs of VR technology would allow more users to access its features, some as end users and some as potential developers, allowing them to discover and correct the shortcomings of VR applications and devices. [ABSTRACT FROM AUTHOR]

The technological advances in the last decades led to radical changes and paradigm shifts in the modern society, replacing the former way of thinking, organizing and acting. More and more traditional services migrate towards internet and cyberspace, the number of those who use digital services growing exponentially in the last several years. In this context, education is one of the main concerns of the society: people must learn and adapt continuously to cope with the current economic and social environment. In this regard, traditional methods are no longer sufficient, so various other forms of education emerged in order to supplement the traditional ones: online education, skills-oriented education, collaborative learning, education at work etc. A rather new, but growing, form of education is the use of massively multiplayer online (MMO) 3D virtual worlds to provide an immersive and entertaining, more practical approach, based on simulation, rich user experience, interaction and collaboration. The technology behind these virtual reality systems is pretty complex, so creating your own application is, in most cases, not possible and will require a serious amount of time, money and human resources. A solution to this problem is to use frameworks dedicated to virtual world creation and management, such as Open Wonderland, Open Simulator or Virtual World Framework. These frameworks contain pre-built open-source solutions that provide working server architecture and also multiple features and services for creating and customizing virtual worlds. Open Simulator is currently one of the most used virtual world frameworks as it is based on Second Life and has strong back-end server architecture able to handle hundreds and even thousands of users. The purpose of this paper is to explore and explain how the Open Simulator framework works, summarize all the provided features, as well as to present several relevant examples that are using the framework to create rich virtual environments. We will also explain some problems encountered when we used the current Open Sim viewers (clients). [ABSTRACT FROM AUTHOR]

Hearing is an extraordinary sense, as the audio signals perceived at the eardrum level of both ears build and define the entire surrounding environment. Sound is seized from all directions, and the listener can identify the distance of the sound source, the amplitude, the arrival time at each ear and the variations of amplitude that differ with changing frequencies. 3D sound is an efficient sensory substitution method that models the elements of the physical world into relevant information for the visually-impaired people. 3D sound is generated by using spectral cues that define how a sound is perceived at a specific location. The majority of virtual-reality audio devices are based on the Head Related Transfer Function (HRTF), a mathematical transformation that describes how the sound is being modified en route from the source until it reaches the inner ear. The main experiments performed in order to investigate human sound localization abilities involved a training and a test session. To test the users' capability to distinguish the sound sources located at various positions in space (azimuth- in the horizontal plane and elevation- in the vertical plane), the sound was played once or several times, as the acoustic signal varied in shape (pink noise, white noise, harmonic sine wave), frequency and duration. Because the brain is a flexible organ that can learn perception of elevation by frequency, a different approach is acoustic coding of elevation, which consists in connecting higher sound frequencies with higher sound sources and lower frequencies of sound with lower sound sources. The main conclusion of the experiments is that the best spatial recognition is achieved by using the white pulse Gaussian noise with a duration of around 100-300ms. Pink and white noise are the most separable sounds, while sine waves are annoying and difficult to localize in the horizontal plane. In addition to this, azimuth spatial resolution is superior to elevation spatial resolution because of the stereoscopic properties of the human auditory system. Also, the sound resolution is better when the initialization phase (training session when the user listens to the sounds for several minutes) lasts longer and when the acoustic signal is periodic and of long continuous duration. [ABSTRACT FROM AUTHOR]

Usually high education is expensive for most of the top universities in the world. Therefore eLearning platforms provide a way of affordable education with an effective cost of investments. In the last decade, cloud computing research and adoption increased greatly due to its many advantages including economic benefits, ease of management, power saving and so on. Mainly, it provides the means to organize and deliver a wide variety of software services including eLearning environments. Along with cloud computing, file systems solutions were improved to meet requirements imposed by the distribution characteristics of clouds. The distribution level offile systems, data management, data seek methods and many other features of distributed file systems, influence performance of eLearning environments. Distributed file systems started with Andrew File System, still used today, continued with Google File System - a parallel and distributed file system suitable for Google search engine and Ceph - one of the most innovative distributed file system, developed a few years ago and considered the new dream network distributed file system. It has a very good distribution level, security, high availability and many other characteristics. Also, clouds are constructed over computer networks topologies. Basically, topologies are different types of graphs, each with a different set of advantages and disadvantages. In this article we have studied how distributed file systems over computer network clusters influence eLearning environments from an architectural point of view and how its performance may be improved. We also propose a high level architecture of cloud platforms more suitable for eLearning software by outlining several advantages that overcome issues related to distributed eLearning. In our proposed architecture, we use Ceph as a data storage environment and several domestic network topologies. In the end, we study how Software Define Network and Open Flow could model the clouds environment in a more suitable way for eLearning applications. [ABSTRACT FROM AUTHOR]

This paper analyzes and compares voltage and power wave reflection coefficients using a visual representation which fully exploits that both coefficients are directly related to the geometry of direct inversive transformations in the extended impedance plane. In order to compare the two concepts for complex impedance ports, the 3D Smith chart tool is used in premiere. The paper gives a geometrical and more intuitive insight of these two parameters and proposes a novel tool for handling both types of reflection coefficients. [ABSTRACT FROM PUBLISHER]

The medical industry is always looking for ways to allow faster and more accurate diagnosis, without the need to expose patients to unnecessary painful and invasive procedures. Faster diagnosis can help hospitals and clinics keep healthcare costs down, while more accurate diagnosis and less stressful procedures can help attract more patients for checkups and investigations. All this can be done nowadays with a relative low cost and without the need for delicate and expensive equipment. Using the new hardware architecture from NVIDIA (CUDA - Compute Unified Device Architecture) every doctor can now use his own computer to conduct those delicate investigations. [ABSTRACT FROM AUTHOR]

Today's computer 3D graphics simulations need to provide a high degree of realism in order to create a rich and credible 3D virtual environment. Ray Tracing is a rendering method that can achieve such a degree of realism compared to the rendering mechanisms used by current graphics hardware. Until recently, Ray Tracing was not suitable to be used as a real time renderer because it is a heavy computational method and the hardware was not fast enough. in this paper we are proposing a solution to run Ray Tracing as a Multi GPGPU (General-purpose computing on graphics processing units ) program and see how well Ray Tracing scales when implemented on multiple GPUs. [ABSTRACT FROM AUTHOR]