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Abstract

The paper presents the use of visual evoked potentials VEP to the objective assessment of visual acuity. Methods of using visual evoked potentials (VEP) rely on the assessment of changes of the electrical action potentials generated within the cortex. To diagnose the degree of weakening eyesight a series of studies on healthy people and visually impaired ones were made. Electrophysiological studies of the eye, using noninvasive VEP examination allow a noninvasive and objective assessment of visual acuity. The use of visual evoked potentials gives the objectivity in assessment of visual acuity what may be very important in ophthalmology. This particularly may concern children examination, people with mental retardation and suspected of simulation.

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Authors and Affiliations

Arkadiusz Hulewicz
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Abstract

Praca prezentuje metodę inwentaryzacji widokowej i jej wykorzystanie we współczesnym wcieleniu znanej od wieków w kulturze dalekiego wschodu, a chętnie stosowanej na przestrzeni lat i epok stylowych idei widoku zapożyczonego (zapożyczonej scenerii).
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Authors and Affiliations

Michał Zieliński
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Abstract

When Zamość was being built the Fortress was in a close connection with the geometry of view. This was reflected both in the utilitarian and aesthetic sphere and concerned the urban scale as well as the scale of long exposure. The visual study conducted within the Study of the shaping of postfortress areas of Zamość Fortress allowed for assessing the contemporary state of exposure and for identification of the correction opportunities. The effect of the study has become the essential element of the design concept in both the compositional and in the part related to the tourist access.

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Authors and Affiliations

Urszula Forczek-Brataniec
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Abstract

Visualizations of mathematical functions have myriad applications in our daily lives, from the economy all the way to medicine.
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Authors and Affiliations

Paweł Dłotko
1

  1. Institute of Mathematics, Polish Academy of Sciences, Warsaw
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Abstract

The objective of the present deliberations was to systematise our knowledge of static visual variables used to create cartographic symbols, and also to analyse the possibility of their utilisation in the Augmented Reality (AR) applications on smartphone-type mobile devices. This was accomplished by combining the visual variables listed over the years by different researchers. Research approach was to determine the level of usefulness of particular characteristics of visual variables such as selective, associative, quantitative and order. An attempt was made to provide an overview of static visual variables and to describe the AR system which is a new paradigm of the user interface. Changing the approach to the presentation of point objects is caused by applying different perspective in the observation of objects (egocentric view) than it is done on traditional analogue maps (geocentric view). Presented topics will refer to the fast-developing field of cartography, namely mobile cartography. Particular emphasis will be put on smartphone-type mobile devices and their applicability in the process of designing cartographic symbols.
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Authors and Affiliations

Łukasz Halik
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Abstract

A mine cannot function without monitoring systems: environmental, basic mining machinery and equipment. The exploitation of ore in the mine depends heavily on properly functioning machines and mining equipment, and acceptable for the miner technical environmental conditions occurring in underground excavations. The monitoring systems of the technical environment in underground mines are primarily telemetry and gasometry systems. The first part of the article shows the typical structure of gasometry systems operating in the Polish underground mines. The existing provisions include the so-called security systems of the mining plant. The article presents a quantitative summary of the telephone exchange types and count of main telecommunication lines operating in these systems. Monitoring systems of machines and mining equipment are an essential element of the effec-tive management of the mine, because they affect the safe operation and increase time of effi-ciency equipment. The second part of the article shows selected monitoring systems of mining machinery and equipment currently used in the dispatcher rooms of mines. Attention was paid to the monitoring systems, which are only software tools as well as those in which additionally use dedicated IT solutions for these systems, hardware and measuring tools. The table shows the types of monitoring systems and technological configurations used in underground mines, preferred for them.

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Authors and Affiliations

Antoni Wojaczek
Adam Wojaczek
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Abstract

Background: Observing one’s own body has been shown to influence pain perception—a phenomenon called visual analgesia. The effect was originally obtained using a mirror reflection of one’s own hand and later replicated with prosthetic and virtual hands. Most studies show increased pain thresholds during visual analgesia, but the opposite effect can be obtained by inducing ownership illusion over a limb that looks wounded. We tested the hypothesis that a resilient-looking virtual limb would lead to an increased pain threshold.
Methods: Eighty-eight students (Mage = 21.4, SDage = 2.98) participated in a within-group experimental design study (natural hand virtual reality [VR], marble hand VR, and non-VR control). In both VR conditions, a visuo-tactile synchronous stimulation was used to elicit the illusion of embodiment. Pressure pain stimulus was applied to the forearm. Dependent variables were: pressure pain threshold, pain intensity and self-reported embodiment.
Results: There were significant differences between the control condition and the Natural Hand VR (V = 647, p < .0001), and between the control condition and the Marble Hand VR (V = 947.5, p < .005), but not between the Natural Hand and Marble Hand conditions (V = 1428.5, p = .62). Contrary to our predictions, pain threshold was higher in the control condition. Pain intensity differences were not significant.
Conclusions: We obtained a significant effect in the opposite direction than predicted. Such results may mean that the visual analgesia effect is more context-dependent than previously thought. We discuss methodological differences between the paradigm used in this study and paradigms reported in the literature as a possible explanation.
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Authors and Affiliations

Marcin Czub
1
ORCID: ORCID
Joanna Piskorz
1
ORCID: ORCID

  1. Uniwersytet Wrocławski, Instytut Psychologii
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Abstract

The aim of the study was to examine the relationships of Level -1/Level -2 visual perspective -taking (VPT -1/VPT -2) with theory of mind (ToM) and executive function (EF). Seventy -six adults aged 18 to 48 years participated in the study. To compare the relationships of the two levels of perspective -taking with the aforementioned abilities, the same stimuli were used in both Level -1 and Level -2 trials of the VPT task. ToM abilities were evaluated with the Strange Story task, and EF using the TMT and WCST tests. It was found that controlling for age -related differences, VPT -1 was not associated with either ToM or such components of EF as executive control and set -shifting. VPT -2 was positively related to ToM, but it was not related to EF. The relationship between VPT -2 and ToM was specific, not mediated by domain -general processing capabilities. The obtained results provide further evidence to support the view that distinct mechanisms underlie Level -1 and Level -2 perspective -taking.

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Authors and Affiliations

Agata Złotogórska -Suwińska
Adam Putko
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Abstract

The paper presents the results of simulations and experiments in the field of control of the low damping and time delay oscillating system. This system includes a quadcopter hovering at a very low altitude, and the altitude is controlled. The time delay is introduced mainly by the remote control device. In order to handle the quadcopter at low altitudes, a proportional-integral controller with a negative proportional coefficient is used. Such an approach can provide good results in the case of an oscillating, low damped system. This method of steering, which uses a typical radio control transmitter, can be used on any commercially available leisure drone. Feedback is provided by a camera and algorithms of computer vision. The presented results were obtained experimentally using free flight – without a harness. Different types of controllers are used to control horizontal shift and altitude.
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Bibliography

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Authors and Affiliations

Konrad Urbański
1
ORCID: ORCID

  1. Institute of Robotics and Machine Intelligence, Poznan University of Technology, Piotrowo 3A str., 60-965 Poznan, Poland
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Abstract

The book outlines the artistic events accompanying the large sports events in 1928: the 9th Olympic Games in Amsterdam and the 1st Summer Spartakiad in Moskow and 2nd Summer Spartakiad planned in Prague, which, however, was cancelled. The organization, character, and cultural influence of these events are outlined, while selected works of art connected to these events are analysed in meticulous detail. The author points out the general differences between the Olympic Games and the Spartakiads both in the approach to sports events, and the accompanying artistic events. The Olympic Games stressed the individualistic approach to art and creative work, and encouraged international competition. The Spartakiads were aiming at collective approach to both art and sports, which were seen not as competition between nations, but a collective effort of the Proletariat.

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Authors and Affiliations

Helena Postawka-Lech
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Abstract

The article is a review of the book by Natalie Zemon Davis Slaves on Screen. Film and Historical Vzsion, Cambridge Mass. 2000.
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Authors and Affiliations

Piotr Witek
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Abstract

The objective of the research was to investigate the efficiency of selected methods of data fusion from visual sensors used on-board satellites for attitude measurements. Data from a sun sensor, an earth sensor, and a star tracker were fused, and selected methods were applied to calculate satellite attitude. First, a direct numerical solution, a numerical and analytical solution of the Wahba problem, and the TRIAD method for attitude calculation were compared used for integrating data produced by a sun sensor and an earth sensor. Next, attitude data from the star tracker and earth/sun sensors were integrated using two methods: weighted average and Kalman filter. All algorithms were coded in the MATLAB environment and tested using simulation models of visual sensors. The results of simulations may be used as an indication for the best data fusion in real satellite systems. The algorithms developed may be extended to incorporate other attitude sensors like inertial and/or GNSS to form a complete satellite attitude system.
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Bibliography

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Authors and Affiliations

Janusz Narkiewicz
1
ORCID: ORCID
Mateusz Sochacki
1
ORCID: ORCID
Adam Rodacki
1
Damian Grabowski
1

  1. Warsaw University of Technology, Faculty of Power and Aeronautical Engineering, Institute of Aeronautics and Applied Mechanics, ul. Nowowiejska 24, 00-665 Warsaw, Poland
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Abstract

The Author discusses very popular interpretations of historical picture by Jan Matejko titled Eros in Despair. Jan Matejko’s Stanczyk on Queen Bona’s Party. This is one the most known historical picture in Poland associated with extremely reach symbolic meaning. Słoczyński argues that major part of existing interpretations are rather a result of sublimation of Polish history as well as anticipation of the symbolic character of later Matejko’s masterpieces than the opinion based on a correct analysis of the discussed picture.
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Authors and Affiliations

Henryk Słoczyński
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Abstract

The application of solid-state light sources in luminaires creates a new quality in illumination design works. In a confrontation with a commonly used but relatively unattractive flood method, the use of small-size luminaires allows one to present an illuminated architectural object in a more attractive way in the evening and at night. In this case, it is possible to apply the principles of illumination described in the literature, especially the principle of height amplification and the principle of depth amplification. The conceptual work of illumination with the use of a large number of small-size luminaires does not require the use of supporting graphical tools, but the specification of actual lighting equipment using only polygonal samples in this case is not possible. The paper presents selected issues of the key stages of the completed work. Using specialized computer software, a geometric model of the architectural object has been developed, facade materials have been parameterized, models of small-size illuminating equipment have been selected and, finally, calculations of luminance distribution on illuminated surfaces have been carried out. As a result of computer work, luminance distributions and photorealistic visualizations of illuminations from defined main directions of observation were obtained. The Lubomirski Palace in Przemysl is an example of the architectural object indicated for detailed works.
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Authors and Affiliations

Antoni Różowicz
1
ORCID: ORCID
Henryk Wachta
2
Sebastian Różowicz
1
ORCID: ORCID

  1. Department of Industrial Electrical Engineering and Automatic Control, Kielce University of Technology, Tysiaclecia Panstwa Polskiego 7, 25-314 Kielce, Poland
  2. Department of Power Electronics and Power Engineering, Rzeszow University of Technology, Wincentego Pola 2, 35-959 Rzeszow, Poland
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Abstract

This paper analyses the use of table visual variables of statistical data of hospital beds as an important tool for revealing spatio-temporal dependencies. It is argued that some of conclusions from the data about public health and public expenditure on health have a spatio-temporal reference. Different from previous studies, this article adopts combination of cartographic pragmatics and spatial visualization with previous conclusions made in public health literature. While the significant conclusions about health care and economic factors has been highlighted in research papers, this article is the first to apply visual analysis to statistical table together with maps which is called previsualisation.
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Authors and Affiliations

Beata Medyńska-Gulij
Paweł Cybulski
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Abstract

In building speech recognition based applications, robustness to different noisy background condition is an important challenge. In this paper bimodal approach is proposed to improve the robustness of Hindi speech recognition system. Also an importance of different types of visual features is studied for audio visual automatic speech recognition (AVASR) system under diverse noisy audio conditions. Four sets of visual feature based on Two-Dimensional Discrete Cosine Transform feature (2D-DCT), Principal Component Analysis (PCA), Two-Dimensional Discrete Wavelet Transform followed by DCT (2D-DWT- DCT) and Two-Dimensional Discrete Wavelet Transform followed by PCA (2D-DWT-PCA) are reported. The audio features are extracted using Mel Frequency Cepstral coefficients (MFCC) followed by static and dynamic feature. Overall, 48 features, i.e. 39 audio features and 9 visual features are used for measuring the performance of the AVASR system. Also, the performance of the AVASR using noisy speech signal generated by using NOISEX database is evaluated for different Signal to Noise ratio (SNR: 30 dB to −10 dB) using Aligarh Muslim University Audio Visual (AMUAV) Hindi corpus. AMUAV corpus is Hindi continuous speech high quality audio visual databases of Hindi sentences spoken by different subjects.
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Authors and Affiliations

Prashant Upadhyaya
Omar Farooq
M.R. Abidi
Priyanka Varshney
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Abstract

Based on the mould temperature measured by thermocouples during slab continuous casting, a difference of temperature thermograph is developed to detect slab cracks. In order to detect abnormal temperature region caused by longitudinal crack, the suspicious regions are extracted and divided by virtue of computer image processing algorithms, such as threshold segmentation, connected region judgement and boundary tracing. The abnormal regions are then determined and labeled with the eight connected component labeling algorithm. The boundary of abnormal region is also extracted to depict characteristics of longitudinal crack. Based on above researches, longitudinal crack with abnormal temperature region can be detected and is different from other abnormalities. Four samples of temperature drop are picked up to compare with longitudinal crack on the abnormal region formation, length, width, shape, et al. The results show that the abnormal region caused by longitudinal crack has a linear and vertical shape. The height of abnormal region is more than the width obviously. The ratio of height to width is usually larger than that of other temperature drop regions. This method provides a visual and easy way to detect longitudinal crack and other abnormities. Meanwhile it has a positive meaning to the intelligent and visual mould monitoring system of continuous casting.
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Authors and Affiliations

Y. Liu
Y. Gao
X. Wang
Y. Sun
Du F.
F. Wang
J. Wang
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Abstract

In this paper, we present an optimization mechanism for two popular landmark-based mobile robot visual homing algorithms (ALV and HiSS), called vector pre-assigned mechanism (VPM). VPM contains two branches, both of which can promote the homing performance effectively. In addition, to make the landmark distribution satisfy the equal distance assumption, a landmark optimization strategy is proposed based on imaging principle of the panoramic vision. Experiments on both panoramic image database and a real mobile robot have confirmed the effectiveness of the proposed methods.

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Authors and Affiliations

X. Ji
Q. Zhu
J. Wang
C. Cai
J. Ma
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Abstract

During the IceAGE ( Icelandic marine Animals – Genetics and Ecology ) expeditions in waters around Iceland and the Faroe Islands in 2011 and 2013, visual assessments of habitats and the study of surface sediment characteristics were undertaken in 119–2750 m water depth. Visual inspection was realized by means of an epibenthic sled equipped with a digital underwater video camcorder and a still camera. For determination of surface sediment characteristics a subsample of sediment from box corer samples or different grabs was collected and analyzed in the lab. Muddy bottoms predominated in the deep basins (Iceland Basin, Irminger Basin, deep Norwegian and Iceland Seas), while sand and gravel dominated on the shelves and the ridges, and in areas with high currents. Organic contents were highest in the deep Norwegian and Iceland Seas and in the Iceland Basin, and at these sites dense aggregations of mobile epibenthic organisms were observed. Large dropstones were abundant in the Iceland Sea near the shelf and in the Denmark Strait. The dropstones carried diverse, sessile epibenthic fauna, which may be underestimated using traditional sampling gear. The paper supplies new background information for studies based on IceAGE material, especially studies related to ecology and taxonomy.
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Authors and Affiliations

Karin Meißner
Nils Brenke
Jörundur Svavarsson
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Abstract

Purpose: to demonstrate the possibility of finding features reliable for more precise distinguishing between normal and abnormal Pattern Electroretinogram (PERG) recordings, in Continuous Wavelet Transform (CWT) coefficients domain. To determine characteristic features of the PERG and Pattern Visual Evoked Potential (PVEP) waveforms important in the task of precise classification and assessment of these recordings. Material and methods: 60 normal PERG waveforms and 60 PVEPs as well as 47 PERGs and 27 PVEPs obtained in some retinal and optic nerve diseases were studied in the two age groups (<= 50 years, > 50 years). All these signals were recorded in accordance with the guidelines of ISCEV in the Laboratory of Electrophysiology of the Retina and Visual Pathway and Static Perimetry, at the Department and Clinic of Ophthalmology of the Pomeranian Medical University. Continuous Wavelet Transform (CWT) was used for the time-frequency analysis and modelling of the PERG signal. Discriminant analysis and logistic regression were performed in statistical analysis of the PERG and PVEP signals. Obtained mathematical models were optimized using Fisher F(n1; n2) test. For preliminary evaluation of the obtained classification methods and algorithms in clinical practice, 22 PERGs and 55 PVEPs were chosen with respect to especially difficult discrimination problems (“borderline” recordings).

Results: comparison between the method using CWT and standard time-domain based analysis showed that determining the maxima and minima of the PERG waves was achieved with better accuracy. This improvement was especially evident in waveforms with unclear peaks as well as in noisy signals. Predictive, quantitative models for PERGs and PVEPs binary classification were obtained based on characteristic features of the waveform morphology. Simple calculations algorithms for clinical applications were elaborated. They proved effective in distinguishing between normal and abnormal recordings.

Conclusions: CWT based method is efficient in more precise assessment of the latencies of the PERG waveforms, improving separation between normal and abnormal waveforms. Filtering of the PERG signal may be optimized based on the results of the CWT analysis. Classification of the PERG and PVEP waveforms based on statistical methods is useful in preliminary interpretation of the recordings as well as in supporting more accurate assessment of clinical data.

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Authors and Affiliations

K. Penkala
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Abstract

Previous research reported about high comorbidity between asthma and neurodevelopmental disorders. Recently, asthma was associated also with executive functions poorness. The current study aimed to investigate the verbal and visual memory performances among fifteen asthmatic kindergarten children compared to the performances of other fifteen healthy kindergarten children. The results showed that the asthmatic group revealed poor performances in the immediate short term verbal memory and the verbal working memory tests but not in the verbal learning test as it was compared to the healthy group. In addition, the asthmatic group revealed poor performances in the visual memory tasks compared to the healthy group. The results were explained in light of the assumption that poor executive functions might be interfere the process of managing the attentional resources which are needed through the process of memory encoding and retrieval.

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Authors and Affiliations

Haitham Taha
Mahmood Khalil

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