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This paper presents computer and color vision research focusing on human color perception in VR environments. A VR art gallery with digital twins of original artworks is created for this experiment. In this research, the field of colorimetry and the application of the L*a*b* and RGB color models are applied. The inter-relationships of the two color models are applied to create a color modification of the VR art gallery environment using C# Script procedures. This color-edited VR environment works with a smooth change in color tone in a given time interval. At the same time, a sudden change in the color of the RGB environment is defined in this interval. This experiment aims to record a user's reaction embedded in a VR environment and the effect of color changes on human perception in a VR environment. This research uses lie detector sensors that record the physiological changes of the user embedded in VR. Five sensors are used to record the signal. An experiment on the influence of the user's color perception in a VR environment using lie detector sensors has never been conducted. This research defines the basic methodology for analyzing and evaluating the recorded signals from the lie detector. The presented text thus provides a basis for further research in the field of colors and human color vision in a VR environment and lays an objective basis for use in many scientific and commercial areas. [ABSTRACT FROM AUTHOR]

This article describing newly build tract for measuring regenerative heat exchangers. At the beginning of this work is summarised measuring of heat recovery exchangers, parameters of heat recovery exchangers and conditions of measurements. This article continuous with the introduction of HVAC laboratory for which new track is built. Particular emphasis is on measuring box in which are exchangers measured.

In this article is examine Laboratory of Environmental Engineering at Faculty of applied informatics under Tomas Bata University in Zlin. This laboratory is performing standardized test of special HVAC equipments. This article describes newly made customization for measuring radiant cooling ceilings. Firstly is described previous situation which is concluded by necessary changes. It is mentioned energy supplies and newly made connection for cooling ceilings. Whole article is sum up by description of samples on which would be done verification of measurement space and methodology.

In this article is covered measurements of radiant cooling ceilings (RCC) in Laboratory of Environmental Engineering at Faculty of applied informatics under Tomas Bata University in Zlin. This laboratory performing standardized tests of special HVAC equipments. Article validate measurements on newly made customization of laboratory for measurements of such RCC. Measurement was performed on RCC with application of PCMs material. This RCC was specially developed for purposes of validation and made in two dimensions. Specific application of PCMs allows achieving recovery of accumulation media in multiple cycles during one day. Outline of newly made RCC is described followed up by detail of set-up of experiment. In article is estimate cooling capacity of used RCC with applied PCMs. Discontinuous cooling cycles is covered as well with description of measured data.

In this article is presented validation of ANSYS Fluent with IEA BESTEST Task 34. Article stars with outlook to the topic, afterward are described steady-state cases used for validation. Thereafter is mentioned implementation of these cases on CFD. Article is concluded with presentation of the simulated results with a comparison of those from already validated simulation software by IEA. These validation shows high correlation with an older version of tested ANSYS as well as with other main software. The paper ends by discussion with an outline of future research.

This article describes measurement of HVAC distribution box on air duct track in Laboratory of Environmental Engineering (LEE). Firstly, the paper describes the LEE and then measurement apparatus with description of calculation methods. Then follows specification of sample with introduction to newly developed equipment for positioning of the anemometer. The evaluation of results of measurements with CFD comparison follows. The article is concluded with discussion over measured data with an outline for further research.

This article describes test methods on air duct track in Laboratory of Environmental Engineering. It focuses on measurement of silencer parameter like is pressure loss coeffcient. Firstly, the paper describe the measurement apparatus with description of calculation method by standard ISO 7235 and energy equation. Then the paper presents three ways how to accomplish measurement because such way is not covered by procedure in standard. Then follows the evaluation of results of measurements on three types of silencer designed for HVAC applications. The article is concluded with discussion over measured data with outline for further research.

Some polymers need a cross-linking agent for the controlled cross-linking process of polymers with a tendency to degradation during the radiation cross-linking process. While, on the other hand, other polymers do not need a cross-linking agent--predominantly there are cross-linking polymers. The Thermo-Plastic Elastomer (TPE) that was used belongs to this group of predominantly cross-linking polymers; however, this agent is added because of faster reaction times and smaller irradiation doses. Microindentation-tensile and tensile impact tests were carried out on a thermoplastic sample--with, and without, a cross-linking agent. Small changes were measured between these materials at low radiation doses, (up to 66 kGy); nevertheless, at higher doses, the influence of the cross-linking agent on the mechanical properties is significant. [ABSTRACT FROM AUTHOR]

This article discusses the possibilities of using radiation cross-linked high density polyethylene (HDPEx) acting as a filler in the original high density polyethylene (HDPE) matrix. The newly created composite is one of the possible answers to questions relating to the processing of radiation cross-linked thermoplastics. Radiation cross-linked networking is—nowadays, a commonly used technology that can significantly modify the properties of many types of thermoplastics. This paper describes the influence of the concentration of filler, in the form of grit or powder obtained by the grinding/milling of products/industrial waste from radiation cross-linked high density polyethylene (rHDPEx) on the mechanical and processing properties and the composite structure. It was determined that, by varying the concentration of the filler, it is possible to influence the mechanical behaviour of the composite. The mechanical properties of the new composite—measured at room temperature, are generally comparable or better than the same properties of the original thermoplastic. This creates very good assumptions for the effective and economically acceptable, processing of high density polyethylene (rHDPEx) waste. Its processability however, is limited; it can be processed by injection moulding up to 60 wt %. [ABSTRACT FROM AUTHOR]

The main advantages of Thermoplastic Polyester Elastomers (TPE-E) are their elastomer properties as well as their ability to be processed in the same way as thermoplastic polymers (e.g., injection moulding, compression moulding and extrusion). However, TPE-Es' properties, mainly their mechanical properties and thermal characteristics, are not as good as those of elastomers. Because of this TPE-Es are often modified with the aim of improving their properties and extending their range of application. Radiation cross-linking using accelerated electron beams is one of the most effective ways to change virgin polymers' properties significantly. Their electrical (that is to say permittivity and resistivity measurements), mechanical (that is, tensile and impact tensile tests), as well as surface (that is, nano-indentation) properties were measured on modified/cross-linked TPE-E specimens with and/or without a cross-linking agent at irradiation doses of 0, 33, 66, 99, 132, 165 and 198 kGy. The data acquired from these procedures show significant changes in the measured properties. The results of this study allow the possibility of determining the proper processing parameters and irradiation doses for the production of TPE-E products which leads to the enlargement of their application in practice. [ABSTRACT FROM AUTHOR]

This article deals with the study of the utilisation of irradiated HDPE products after their end-of-life cycle. Today, polymer waste processing is a matter of evermore intensive discussion. Common thermoplastic waste recycling—especially in the case of wastes with a defined composition—is generally well-known—and frequently used. On the contrary, processing cross-linked plastics is impossible to do in the same way as with virgin thermoplastics—mainly due to the impossibility of remelting them. The possibility of using waste in the form of grit or a powder, made from cross-linked High Density PolyEthylene (rHDPEx) products, after their end-of-life cycle, as a filler for virgin Low Density PolyEthylene (LDPE) was tested in a matrix. It was found that both the mechanical behaviour and processability of new composites with an LDPE matrix, with rHDPEx as a filler, depend—to a high degree—on the amount of the filler. The composite can be processed up to 60% of the filler content. The Polymer Mixture Fluidity dropped significantly, in line with the amount of filler, while the mechanical properties, on the other hand, predominantly grew with the increasing amount of rHDPEx. [ABSTRACT FROM AUTHOR]