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.
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.
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.
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.
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.
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.
The aim of the paper was to develop determination methods of sedimentation characteristics using PIV image anemometry and suspension image analysis. Two methods of the investigation of sed- imentation process based on visualization techniques were developed. In the first one, using PIV method, vector fields of the velocity of settling particles are determined and then average particle velocities are calculated to establish the so called sedimentation dynamics curve. In the second one, the methods of suspension image analysis are utilized to determine the positions of the upper dis- continuity and to establish the sedimentation curve. Laboratory research on the sedimentation of agalit particles suspended in glycerine was conducted (using PIV method). Additionally, industrial research on the sedimentation of water-absorbing granular material used after the first carbonation (carbonation I) was conducted in a sugar factory (using the second method). The research consisted of photographic registration of images of the settling suspension by means of the time-lapse photog- raphy technique. A laboratory study was conducted for four values of the volume concentration of agalit particles in glycerine (0.5; 1.0; 1.5 and 2.0 vol%). The research methodology, the scope of the conducted measurements and sample research results together with conclusions are presented in this paper.
The article presents the use of computer graphics methods and computational geometry for the analysis on changes of geometrical parameters for a mixed zone in resistance-heated samples. To perform the physical simulation series of resistance heating process, the Gleeble 3800 physical simulator, located in the Institute for Ferrous Metallurgy in Gliwice, was used. The paper presents a description of the test stand and the method for performing the experiment. The numerical model is based on the Fourier-Kirchoff differential equation for unsteady heat flow with an internal volumetric heat source. In the case of direct heating of the sample, geometrical parameters of the remelting zone change rapidly. The described methodology of using shape descriptors to characterise the studied zone during the process allows to parametrise the heat influence zones. The shape descriptors were used for the chosen for characteristic timing steps of the simulation, which allowed the authors to describe the changes of the studied parameters as a function of temperature. Additionally, to determine the impact of external factors, the remelting zone parameters were estimated for two types of grips holding the sample, so-called hot grips of a shorter contact area with the sample, and so-called cold grips. Based on the collected data, conclusions were drawn on the impact of the process parameters on the localisation and shape of the mushy zone.