Virtual Reality (VR) systems are used in engineering, architecture, design and in applications of biomedical research. The component of acoustics in such VR systems enables the creation of audio-visual stimuli for applications in room acoustics, building acoustics, automotive acoustics, environmental noise control, machinery noise control, and hearing research. The basis is an appropriate acoustic simulation and auralization technique together with signal processing tools. Auralization is based on time-domain modelling of the components of sound source characterization, sound propagation, and on spatial audio technology. Whether the virtual environment is considered sufficiently accurate or not, depends on many perceptual factors, and on the pre-conditioning and immersion of the user in the virtual environment. In this paper the processing steps for creation of Virtual Acoustic Environments and the achievable degree of realism are briefly reviewed. Applications are discussed in examples of room acoustics, archeological acoustics, aircraft noise, and audiology.

Simulation-based models standing in for the real world are unfettered by any biological, emotional, historical, logical, or practical limitations.

Psychoacoustics is traditionally based on a world model that assumes a physical world existing independently of any observer - the so-called objective world. Being exposed to this world, an observer is impinged upon by a variety of stimuli reaching his/her sensory organs. These stimuli, if physiologically adequate, may cause biological transduction and signal processing in the sensory organs and its afferent pathways in such a way that finally a specific excitation of the cortex takes place, which results in sen-sations to appear in the observer’s perceptual world. The sensations are understood as being subjective, since they require an observer to exist. This world model - also known as (objectivistic) realism - reaches its limits when it comes to explaining more complex phenomena of perception. Thereupon, in this paper, an alternative world model is emphasized and applied to psychoacoustics, namely the perceptionist’s model. Like realism, perceptionism has a long tradition in epistemology. It appears to be suitable to improve our understanding of perceptual organization.

Rapid development of computing and visualisation systems has resulted in an unprecedented capability to display, in real time, realistic computer-generated worlds. Advanced techniques, including three-dimensional (3D) projection, supplemented by multi-channel surround sound, create immersive environments whose applications range from entertainment to military to scientific. One of the most advanced virtual reality systems are CAVE-type systems, in which the user is surrounded by projection screens. Knowledge of the screen material scattering properties, which depend on projection geometry and wavelength, is mandatory for proper design of these systems. In this paper this problem is addressed by introducing a scattering distribution function, creating a dedicated measurement setup and investigating the properties of selected materials used for rear projection screens. Based on the obtained results it can be concluded that the choice of the screen material has substantial impact on the performance of the system

The article presents a brief exposition of alternative ways of creating virtual objects and the status of their existence inspired by the relevant views of Plato, Aristotle, Franz Brentano and Karl Popper as well as various conceptions of representation. I argue that the present state of research on the problem of “computer” virtuality shows that it is necessary to explore first the ontological issues of virtual objects. Only these issues will solve the mystery of the creation and existence of virtual objects. The consideration of these issues are suppressed by the fact that contemporary philosophy has removed both metaphysics and, with-it, ontology. That is why, and for reasons for reasons of substantive accuracy, I show how traditional ontological and ontologically inspiring approaches are—when modified— promising candidates for exploring the nature of virtual objects, first of all, problems of their existence and creation.

Gaston Milhaud rejects the principle of contradiction if it is conceived as an absolute and universal rule. He claims that it only holds in some narrowly defined circumstances. According to him, the greater is mental contribution to an act of cognition the more appropriate is the application of the principle of contradiction. My analysis of his views shows that he wanted to emphasize the differences between the objective reality and its mental or linguistic representations rather than undermine the logical principle of contradiction. Parallels can be noted between Milhaud’s views on contradiction and Leon Chwistek’s theory of the multiplicity of realities, as well as Kazimierz Ajdukiewicz’s concept of the cognitive role of language.

The paper tries to defend the thesis that it is impossible to decide upon moral issues without any references to the ontology of the world we live in. An illustrative example of the main argumentation line is the choice made by Cypher—a second plan character in the movie Matrix. Cypher decides to betray human rebels fighting against machines for freedom and, as a reward, accepts affluent life in the virtual reality. His choice seems to be superficially reprehensible because of the abandonment of the real world and authentic life. However, one can argue that the dichotomy between the real and virtual world is seeming. By choosing the virtual reality Cypher decided to act in a world which, like the real world, makes it possible to be a moral subject and enables authentic experience. The difference between both the worlds lies in the type of determination limiting any conscious subject. Cypher prefers to live in a world determined by the algorithm of Matrix more than in a world where his behaviour is determined by genes and other biological factors.

This paper analyses the performance of Differential Head-Related Transfer Function (DHRTF), an alternative transfer function for headphone-based virtual sound source positioning within a horizontal plane. This experimental one-channel function is used to reduce processing and avoid timbre affection while preserving signal features important for sound localisation. The use of positioning algorithm employing the DHRTF is compared to two other common positioning methods: amplitude panning and HRTF processing. Results of theoretical comparison and quality assessment of the methods by subjective listening tests are presented. The tests focus on distinctive aspects of the positioning methods: spatial impression, timbre affection, and loudness fluctuations. The results show that the DHRTF positioning method is applicable with very promising performance; it avoids perceptible channel coloration that occurs within the HRTF method, and it delivers spatial impression more successfully than the simple amplitude panning method.

The use of virtual reality (VR) has been exponentially increasing and due to that many researchers have started to work on developing new VR based social media. For this purpose it is important to have an avatar of the user which look like them to be easily generated by the devices which are accessible, such as mobile phones. In this paper, we propose a novel method of recreating a 3D human face model captured with a phone camera image or video data. The method focuses more on model shape than texture in order to make the face recognizable. We detect 68 facial feature points and use them to separate a face into four regions. For each area the best fitting models are found and are further morphed combined to find the best fitting models for each area. These are then combined and further morphed in order to restore the original facial proportions. We also present a method of texturing the resulting model, where the aforementioned feature points are used to generate a texture for the resulting model.

In the article the author discusses the relationship between education and socio-cultural needs. The socio – cultural reality is the reality of a permanent change. It is difficult to describe and even more difficult to understand. The specific character of qualitatively new changes in the relations between globality and locality implies a completely new perception of reality, ways of interpreting the world, and a new quality of judgments about the condition of the modern man. This reality is also a ”multiplicity of worlds”, which means a large number of possibilities to create oneself. What individuals perceive as their ”own” has the biggest developmental potential when it is worked out on the proactivity path. proactive people are distinguished by interrelated features: the search for a possibility of change (the environment examination, going beyond limitations of a given situation), establishing effective and change oriented goals (opening new paths of action), foreseeing problems and remedia measures (the analysis of one’s own achievements, looking for signals of threats or dangers), looking for new ways of achieving goals (the ambition is to make a new tradition).

Virtual reality (VR) technology now provides players with immersive and realistic experiences as never before. Spatial presence plays a crucial role in the introduction of immersive experience in a VR environment. Spatial presence is a special feeling of personal and physical presence in the displayed environment. In this study, we found that the first-person perspective (1PP) was more effective in raising the sense of spatial presence that induces immersive experience compared to the third-person perspective (3PP) in a VR shooting game. Moreover, eye blink rate was significantly higher in the 1PP compared with the 3PP. The 1PP game setting was more realistic than the 3PP setting, and may have raised participants’ sense of immersion and facilitated eye blink. These results indicate that eye blink rate is increased by the sense of spatial presence, and can be a good measure of subjective immersive experience in a VR environment. Neuroscientific evidences suggest that dopaminergic system is involved in such emotional experiences and physiological responses.

In recent years, many scientific and industrial centres in the world developed a virtual reality systems or laboratories. The effect of user “immersion” into virtual reality in such systems is largely dependent on optical properties of the system. In this paper, problems of luminance distribution uniformity in CAVE-type virtual reality systems are analyzed. For better characterization of CAVE luminance nonuniformity corner and edge CAVE nonuniformity were introduced. Based on described CAVE-type virtual reality laboratory, named Immersive 3D Visualization Lab (I3DVL) just opened at the Gdansk University of Technology, luminance nonuniformity of the system is evaluated and discussed. Data collection of luminance distribution allows for software compensation of intensity distribution of individual images projected onto the screen (luminance non-uniformity minimization) in the further research.

The paper takes under scrutiny Michael Köhlmeier’s novel Abendland, which portrays the history of the twentieth century in the form of oral family stories based on the biography of the main protagonist of the work, Carl Jacob Candoris, written down by his godson Sebastian Lukasser. Authentic historical events and actual characters are intermingled with fictitious figures and events. The article poses questions on individual and collective memory as well as the significance of oral history in the life of an individual.