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Abstract

In the article, three types of proximity sensors that might be used in bicycle rangefinder to measure the distance between the bicycle and an overtaking car are compared. The influence of various factors on the accuracy of the distance measurements obtained using ultrasonic, infrared and laser sensors is tested, among others, light conditions, car surface type and colour, rain, pollination and vibrations.
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Bibliography

[1] M. De Angelis, V.M. Puchades, F. Fraboni, L. Pietrantoni, and G. Prati, “Negative attitudes towards cyclists influence the acceptance of an in-vehicle cyclist detection system,” Transportation Research Part F: Traffic Psychology and Behaviour, vol. 49, pp. 244–256, Aug. 2017. DOI: https://doi.org/10.1016/j.trf.2017.06.021
[2] E. Robartes, and T. D. Chen, “Crash histories, safety perceptions, and attitudes among Virginia bicyclists.” Journal of Safety Research, vol. 67, pp. 189–196, Dec. 2018. DOI: https://doi.org/10.1016/j.jsr.2018.10.009
[3] I. Walker, I. Garrard, and F. Jowitt, “The influence of a bicycle commuter's appearance on drivers’ overtaking proximities: An on-road test of bicyclist stereotypes, high-visibility clothing and safety aids in the United Kingdom,” Accident Analysis & Prevention, vol. 64, pp. 69–77, Mar. 2014. DOI: https://doi.org/10.1016/j.aap.2013.11.007
[4] B. Beck, D. Chong, J. Olivier, M. Perkins, A. Tsay, A. Rushford, L. Li, P. Cameron, R. Fry, and M. Johnson, “How much space do drivers provide when passing cyclists? Understanding the impact of motor vehicle and infrastructure characteristics on passing distance,” Accident Analysis & Prevention, vol. 128, pp. 253–260, Jul. 2019. DOI: https://doi.org/10.1016/j.aap.2019.03.007
[5] M. O'Reilly, “The device that measures cyclist passing distances,” http://www.executivestyle.com.au/the-device-that-measures-cyclist-passing-distances-gpehki (accessed on 8 July 2020).
[6] M. Dozza, R. Schindler, G. Bianchi-Piccinini, and J. Karlsson, “How do drivers overtake cyclists?” Accident Analysis & Prevention, vol. 88, pp. 29-36, Mar. 2016. DOI: https://doi.org/10.1016/j.aap.2015.12.008
[7] C3FT v1 | Codaxus LLC: http://codaxus.com/c3ft/c3ft-v1/ (accessed on 8 July 2020).
[8] C3FT v2 | Codaxus LLC: http://codaxus.com/c3ft/c3ft-v2/ (accessed on 8 July 2020).
[9] C3FT v3 | Codaxus LLC. http://codaxus.com/c3ft/c3ft-v3/ (accessed on 8 July 2020).
[10] A. K. Debnath, N. Haworth, A. Schramm, K. C.Heesch, and K. Somoray, “Factors influencing noncompliance with bicycle passing distance laws,”, Accident Analysis & Prevention, vol. 115, pp. 137-142, Jun. 2018. DOI: https://doi.org/10.1016/j.aap.2018.03.016
[11] J. Coburn, “Distance Sensor.” In: Build Your Own Car Dashboard with a Raspberry Pi. Apress, Berkeley, CA (2020). DOI: https://doi.org/10.1007/978-1-4842-6080-7_13
[12] Heckathorn, B.; MacPherson, T.; Schumacher, T., “ Distance Sensors,” http://www.eecs.umich.edu/courses/eecs270/270lab/270_docs/Distance%20Sensor%20Presentation.pdf (accessed on 8 July 2020).
[13] B.G. Pavithra, P. Siva Subba Rao, A. Sharmila, S. Raja, and S.J.Sushma, “Characteristics of different sensors used for Distance Measurement,” International Research Journal of Engineering and Technology (IRJET), vol. 4, pp. 698-702, Dec. 2017.
[14] S. Adarsh, S. Mohamed Kaleemuddin, B. Dinesh, and K.I. Ramachandran, “Performance comparison of Infrared and Ultrasonic sensors for obstacles of different materials in vehicle/ robot navigation applications,” Proc. IOP Conf. Series: Materials Science and Engineering, 149, 2016. DOI: 10.1088/1757-899X/149/1/012141
[15] J. Majchrzak, M. Michalski, and G. Wilczyński, “Distance Estimation With a Long-Range Ultrasonic Sensor System,” IEEE Sensors Journal, vol. 9, pp. 767–773, 2009.
[16] T. Mohammad, “Using Ultrasonic and Infrared Sensors for Distance Measurement,” International Journal of Mechanical and Mechatronics Engineering, vol. 3, no. 3, pp. 273-278, 2009.
[17] S. Rzydzik, A. Saltarski, M. Roziński, and K Psiuk, “Infrared Distance Sensors for Autonomous Model of Truck with Semi-trailer,” 2020 6th International Conference on Mechatronics and Robotics Engineering (ICMRE), Barcelona, Spain, 2020, pp. 104-109 (2020). DOI: 10.1109/ICMRE49073.2020.9065091
[18] W. Xu, C. Yan, W. Jia, X, Ji, and J. Liu, “Analyzing and Enhancing the Security of Ultrasonic Sensors for Autonomous Vehicles,” IEEE Internet of Things Journal, vol. 5, no. 6, pp. 5015–5029, Dec. 2018. DOI: 10.1109/JIOT.2018.2867917.
[19] R. Burnett, Ultrasonic vs Infrared (IR) Sensors – Which is better? https://www.maxbotix.com/articles/ultrasonic-or-infrared-sensors.htm (accessed on 8 July 2020).
[20] Distance Sensor Comparison Guide. https://www.sparkfun.com/distance_sensor_comparison_guide (accessed on 8 July 2020).
[21] HC-SR04 (ultrasound) vs Sharp GP2Y0A02YK0F (IR) vs VL53L0X (Laser), which solution to choose for distance measurement with Arduino or Raspberry Pi. https://diyprojects.io/hc-sr04-ultrasound-vs-sharp-gp2y0a02yk0f-ir-vl53l0x-laser-solutions-choose-distance-measurement-arduino-raspberrypi/#.XSWSkBLTAsc (accessed on 8 July 2020).
[22] https://diyprojects.io/proximity-sensor-a02yk0-test-calibration-sharp-gp2y0a02yk0f-asian-clone/#.XSMH7xLTAsc (accessed on 8 July 2020).
[23] Product User’s Manual – HC-SR04 Ultrasonic Sensor. Cytron Technologies, 2013. GP2Y0A02YK0F. Sharp Corporations, 2006
[24] A. Szydło, A device that measures the distance between a bicycle and a car. Master thesis written under supervision of Bartłomiej Zieliński, Silesian University of Technology, Institute of Computer Science, Gliwice 2017 [in Polish].
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Authors and Affiliations

Bartłomiej Zieliński
1

  1. Silesian University of Technology, Poland
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Abstract

The benefits of Lagos spinach ( Celosia argentea L.) as a medicinal plant and leafy vegetable encourage its production. However, goat weed ( Ageratum conyzoides L.) is a common weed in the agroecological region where C. argentea thrives. Evaluation of the goat weed effect on C. argentea is necessary since the impact of crop-weed interaction varies with species and density. A screen-house study comprising a C. argentea plant with 0, 2, 4, 6, 8, and 10 goat weed plants per pot were laid out in a completely randomized design and replicated six times. The experimental treatments were equivalent to 0, 100, 200, 300, 400, and 500 goat weed plants per square meter. Growth parameters of C. argentea, such as plant height, number of leaves and number of branches, were recorded weekly. The study also analyzed weight, moisture, ash, lipid, dietary fiber, protein, and carbohydrate content of C. argentea after harvest. The results showed that all the goat weed densities negatively impacted the growth of C. argentea. However, 8 and 10 goat weed plants per pot seemed to have the greatest effect on the growth of C. argentea. The moisture content, ash, crude protein, and crude fiber of C. argentea were significantly reduced by 50–60%, 60–69%, 45–56%, and 42–54%, respectively, due to the goat weed densities, whereas the carbohydrate content increased. Hence, goat weed should be maintained at less than 100 plants per square meter to prevent quantitative and qualitative losses.
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Authors and Affiliations

Olatunde Philip Ayodele
1

  1. Department of Agronomy, Adekunle Ajasin University, Akungba-Akoko, Ondo State, Nigeria
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Abstract

Voting power methodology offers insights to understand coalition building in collective decision making. This paper proposes a new measure of voting power inspired from Banzhaf (1965) accounting for the proximity between voters by capturing how often they appear in winning coalitions together. Using this proximity index, we introduce a notion of relative linkages among coalition participants as determinant of coalition building. We propose an application to the governance structure of the International Monetary Fund, with linkages being represented by bilateral volumes of trade between voters. The results are able to explain several important features of the functioning of this particular voting body, and may be useful for other applications in international politics.

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Authors and Affiliations

Julien Reynaud
Fabien Lange
Łukasz Gątarek
Christian Thimann
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Abstract

The aim of this paper is presentation and comparison of calculation methods of the inductance matrix of a 3-column multi-winding autotransformer. Main and leakage autotransformer inductance was obtained using finite elements method. Static calculations were made at the current supply for 2D and 3D models, and mono-harmonic calculations were made at the voltage supply. In the mono-harmonic calculations the eddy current losses were taken into account, this made it possible to study relationship between the autotransformer parameters and the frequency. Calculations were made using Ansys and the authors' own programs in Matlab.

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Authors and Affiliations

Marek Gołębiowski
Damian Mazur
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Abstract

The 15-winding and 3-column autotransformer supplying an 18-pulse rectifier circuit was developed. Presented methods can be used also for the autotransformers of other topologies supplying different kinds of converters. Presented methods make it possible to exactly calculate main and leakage inductances of the multi-winding autotransformer. The presented analysis of the eigenvalues and eigenvectors of the inductance matrix makes it possible to identify the influence nature of individual modes on the inductance matrix, and to compare the calculation results obtained using the presented methods. Frequency dependence of autotransformer parameters was shown. Also modes of the impedance matrix of the multi-winding autotransformer was investigated, this made it possible to identify the influence nature of individual modes on the inductance matrix. Using presented methods one can exactly calculate main and leakage inductances of the autotransformer. Thanks to this, one can design in optimal way autotransformers for supplying, for example, rectifier circuits, THD coefficients. The results of the measurements and simulations were also shortly presented at the end of the article.

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Authors and Affiliations

Marek Gołębiowski
Damian Mazur
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Abstract

This paper presents a finite element investigation into the proximity losses in a high-speed permanent magnet (PM) machine for traction applications. A three-dimensional (3D) finite element analysis (FEA) is employed to evaluate and identify the endwinding contribution into the overall winding power loss generated. The study is focused on the end-winding effects that have not been widely reported in the literature. The calculated results confirm that the end-winding copper loss can significantly affect the eddycurrent loss within copper and it should be taken into account to provide reasonable prediction of total losses. Several structures of the end-winding are analyzed and compared in respect to the loss and AC resistance. The results clearly demonstrate that the size of the end-winding has a significant impact on the power loss. The calculated results are validated experimentally on the high-speed permanent magnet synchronous machine (PMSM) prototype for selected various winding arrangements.

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Authors and Affiliations

Adrian Młot
Marian Lukaniszyn
Mariusz Korkosz
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Abstract

This electronic paper presents an innovative technology for efficient use of the radio spectrum. This new frequency reconfigurable rotatable antenna is intended for wireless applications such as WLAN, WiMAX and Bluetooth mobile applications. The working principle of this proposed work is to print square patches mounted on the same circular dielectric substrate feed by a proximity coupling to eliminate the noise signal transmission and problems related to interference. The three positions correspond to an operating frequency controlled by a bipolar step-by-step engine. An optimization of the structure using the FEM finite element method as well as a comparison with other structures recently realized are detailed in this paper. The final numerical simulation results are: WLAN 4.95-5.53 GHz (BW = 11%) Gain = 6.06 dBi, WiMAX 3.35-3.75 GHz (BW = 11.2%) Gain = 7.48 dBi and Bluetooth 2.3-2.51 GHz (BW = 8.7%) Gain = 17.78 dBi.

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Authors and Affiliations

Aziz El Fatimi
Seddik Bri
Adil Saadi
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Abstract

Turkey has 19.3 billion tons of lignite reserves and the vast majority of these Neogene lignite deposits are preferred for use in thermal power plants due to their low calorific value. The calorific value of lignite used in thermal power plants for electricity generation must be kept under constant control. In the control of calorific value, the estimation of the lower and higher heating values (LHV and HHV) of lignite is of great importance. In the literature, there are many studies that establish a relationship between the heating values of coal and proximate and ultimate analysis variables. In the studies dealing with proximate analysis data, it is observed that although the coefficients of the obtained multiple linear regression models (MRM) are statistically insignificant, these models are used to predict heating values because of the meaningful correlation coefficient. In this study, it is investigated whether moderator variables are effective on LHV estimation with proximate analysis data collected from forty-one lignite basins in different regions of Turkey, and a moderator variable analysis (MVA) model is developed to be used for the prediction of LHV. As a result of the study, it is found that the proposed MVA model is in accordance with observation values (coefficient of determination R 2 = 0.951), and absolute and standard errors are also small. Therefore, it is concluded that the use of MVA to estimate the LHV of Turkey’s lignite is found to be more statistically meaningful.
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Authors and Affiliations

Mehmet Aksoy
1
ORCID: ORCID

  1. Eskişehir Osmangazi University, Turkey
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Abstract

Research on improving the performance of microstrip antennas is continuously developing the following technology; this is due to its light dimensions, cheap and easy fabrication, and performance that is not inferior to other dimension antennas. Especially in telecommunications, microstrip antennas are constantly being studied to increase bandwidth and gain according to current cellular technology. Based on the problem of antenna performance limitations, optimization research is always carried out to increase the gain to become the antenna standard required by 5G applications. This research aims to increase the gain by designing a 5-element microstrip planar array antenna arrangement at a uniform distance (lamda/2) with edge weights at a frequency of 2.6 GHz, Through the 1x5 antenna design with parasitic patch, without parasitic, and using proximity coupling.This study hypothesizes that by designing an N-element microstrip planar array antenna arrangement at uniform spacing (lamda/2) with edge weights, a multi-beam radiation pattern character will be obtained so that to increase gain, parasitic patches contribute to antenna performance. This research contributes to improving the main lobe to increase the gain performance of the 1x5 planar array antenna. Based on the simulation results of a 1x5 microstrip planar array antenna using a parasitic patch and edge weighting, a gain value of 7.34 dB is obtained; without a parasitic patch, a gain value of 7.03 dB is received, using a parasitic patch and proximity coupling, a gain value of 2.29 dB is obtained. The antenna configuration with the addition of a parasitic patch, even though it is only supplied at the end (edge weighting), is enough to contribute to the parameters impedance, return loss, VSWR, and total gain based on the resulting antenna radiation pattern. The performance of the 1x5 microstrip planar array antenna with parasitic patch and double substrate (proximity coupling), which is expected to contribute even more to the gain side and antenna performance, has yet to be achieved. The 1x5 planar array antenna design meets the 5G gain requirement of 6 dB.
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Authors and Affiliations

Imelda Uli Vistalina Simanjuntak
1
Sulistyaningsih
2
Heryanto
3
Dian Widi Astuti
1

  1. Universitas Mercu Buana, Indonesia
  2. Badan Riset dan Inovasi Nasional, Indonesia
  3. Institut Teknologi PLN, Indonesia
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Abstract

The COVID-19 pandemic has significantly reduced the number of orthopedic surgeries world-wide. The main reason for this was an introduction of numerous restrictions in the field of mobility, which resulted in reduction of circumstances predisposing to injuries. This had a positive impact on the overall readiness of the health system to fight the pandemic, thanks to saving human and material resources that could be successfully allocated in order to fight a new, previously unknown threat. On the other hand, such aimed administration of the system was not indifferent in terms of care quality directed towards traumatized patients, often requiring immediate measures (risk of infection transmission). This study aims to evaluate in-hospital mortality in patients with COVID-19 operated on proximal femur fractures. An attempt was also made to determine predictors influencing mortality rate among patients operated over the analyzed period.
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Authors and Affiliations

Artur Fałek
1
Szymon Skwarcz
1
Marek Paździor
1

  1. Department of Trauma and Orthopedic Surgery and Spine Surgery, Independent Public Healthcare, Puławy, Poland
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Abstract

Accurate prediction of power loss distribution within an electrical device is highly desirable as it allows thermal behavior to be evaluated at the early design stage. Three-dimensional (3-D) and two-dimensional (2-D) finite element analysis (FEA) is applied to calculate dc and ac copper losses in the armature winding at high-frequency sinusoidal currents. The main goal of this paper is showing the end-winding effect on copper losses. Copper losses at high frequency are dominated by the skin and proximity effects. A time-varying current has a tendency to concentrate near the surfaces of conductors, and if the frequency is very high, the current is restricted to a very thin layer near the conductor surface. This phenomenon of nonuniform distribution of time-varying currents in conductors is known as the skin effect. The term proximity effect refers to the influence of alternating current in one conductor on the current distribution in another, nearby conductor. To evaluate the ac copper loss within the analyzed machine a simplified approach is adopted using one segment of stator core. To demonstrate an enhanced copper loss due to ac operation, the dc and ac resistances are calculated. The resistances ratio ac to dc is strongly dependent on frequency, temperature, shape of slot and size of slot opening.

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Authors and Affiliations

Adrian Młot
Mariusz Korkosz
Piotr Grodzki
Marian Łukaniszyn
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Abstract

The aim of this paper is to derive an analytical equations for the temperature dependent optimum winding size of inductors conducting high frequency ac sinusoidal currents. Derived analytical equations are useful designing tool for research and development engineers because windings made of foil, square-wire, and solid-round-wire windings are considered. Temperature dependent Dowell’s equation for the ac-to-dc winding resistance ratio is given and approximated. Thermally dependent analytical equations for the optimum foil thickness, as well as valley thickness and diameter of the square-wire and solid-round-wire windings are derived from approximated thermally dependent ac-to-dc winding resistance ratios. Minimum winding ac resistance of the foil winding and local minimum of the winding ac resistance of the solid-round-wire winding are verified with Maxwell 3D Finite Element Method simulations.

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Authors and Affiliations

Rafal P. Wojda
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Abstract

Size-dependent dynamic instability of cylindrical nanowires incorporating the effects of Casimir attraction and surface energy is presented in this research work. To develop the attractive intermolecular force between the nanowire and its substrate, the proximity force approximation (PFA) for small separations, and the Dirichlet asymptotic approximation for large separations with a cylinder-plate geometry are employed. A nonlinear governing equation of motion for free-standing nanowires – based on the Gurtin-Murdoch model – and a strain gradient elasticity theory are derived. To overcome the complexity of the nonlinear problem in hand, a Garlerkin-based projection procedure for construction of a reduced-order model is implemented as a way of discretization of the governing differential equation. The effects of length-scale parameter, surface energy and vacuum fluctuations on the dynamic instability threshold and adhesion of nanowires are examined. It is demonstrated that in the absence of any actuation, a nanowire might behave unstably, due to the Casimir induction force.

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Authors and Affiliations

Hamid M. Sedighi
Hassen M. Ouakad
Moosa Khooran
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Abstract

We analyze the Google-Apple exposure notification mechanism designed by the Apple-Google consortium and deployed on a large number of Corona-warn apps. At the time of designing it, the most important issue was time-to-market and strict compliance with the privacy protection rules of GDPR. This resulted in a plain but elegant scheme with a high level of privacy protection. In this paper we go into details and propose some extensions of the original design addressing practical issues. Firstly, we point to the danger of a malicious cryptographic random number generator (CRNG) and resulting possibility of unrestricted user tracing. We propose an update that enables verification of unlinkability of pseudonymous identifiers directly by the user. Secondly, we show how to solve the problem of verifying the “same household” situation justifying exempts from distancing rules. We present a solution with MIN-sketches based on rolling proximity identifiers from the Apple-Google scheme. Thirdly, we examine the strategies for revealing temporary exposure keys. We have detected some unexpected phenomena regarding the number of keys for unbalanced binary trees of a small size. These observations may be used in case that the size of the lists of diagnosis keys has to be optimized.
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Bibliography

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Authors and Affiliations

Adam Bobowski
1
Jacek Cichoń
1
ORCID: ORCID
Mirosław Kutyłowski
1
ORCID: ORCID

  1. Wrocław University of Science and Technology, Wybrzeże Stanisława Wyspiańskiego 27, 50-370 Wrocław, Poland
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Abstract

The article analyses the issue of the potential development of theoretical thinking in young children. The context for this discussion is found in the cultural and historical development theory of L.S. Vygotsky which constitutes the basis for assumptions regarding the thinking about development and education of children. It highlights the elementary education stage as a very important area of designing „developmental teaching” as understood by Vygotsky. The article emphasizes the role of an adult who builds the scaffolding for the child’s thinking and acting, and establishes the conditions and teaching environment necessary for the performance of a cognitive process directed at the development of theoretical thinking. In the author’s opinion building the foundation for theoretical thinking will be possible when teachers set „the right developmental and educational tasks” for a child who is constructing knowledge.

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Authors and Affiliations

Ewa Filipiak
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Abstract

This article focuses on paralogical figures (amphibology, equivocation, hypallage and syllepsis) in the poems of Jan Zych. Paralogicisms are phrases in which the combination of logical and syntactical form produces an irresolvable semantic conundrum. The article is divided into three parts, each dealing with one aspect of Zych’s handling of the opposition of distance and proximity: air metaphors expressive of the channel of poetic speech; communication by post (letters); and images of the labyrinth. The paralogical figures are discussed in terms of their function as textual building-blocks, a mark of the author’s subjectivity, and an invitation for performative reading. In this way, Zych’s poems, in particular Labirynty (The Labyrinths) are reconstituted as literary performances, analogous to the labyrinthine prose of J. L. Borges and Octavio Paz.

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Authors and Affiliations

Dorota Wojda
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Abstract

Simultaneous perception of audio and visual stimuli often causes concealment or misrepresentation of information actually contained in these stimuli. Such effects are called the "image proximity effect" or the "ventriloquism effect" in the literature. Until recently, most research carried out to understand their nature was based on subjective assessments. The authors of this paper propose a methodology based on both subjective and objectively retrieved data. In this methodology, objective data reflect the screen areas that attract most attention. The data were collected and processed by an eye-gaze tracking system. To support the proposed methodology, two series of experiments were conducted - one with a commercial eye-gaze tracking system Tobii T60, and another with the Cyber-Eye system developed at the Multimedia Systems Department of the Gdańsk University of Technology. In most cases, the visual-auditory stimuli were presented using a 3D video. It was found that the eye-gaze tracking system did objectivize the results of experiments. Moreover, the tests revealed a strong correlation between the localization of a visual stimulus on which a participant's gaze focused and the value of the "image proximity effect". It was also proved that gaze tracking may be useful in experiments which aim at evaluation of the proximity effect when presented visual stimuli are stereoscopic.

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Authors and Affiliations

Bożena Kostek
Bartosz Kunka

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