Tomas Bata University in Zlín
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RGB color model: Effect of color change on a user in a VR art gallery using polygraph
Get PDFThis 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.Internal Grant Agency of Tomas Bata University [IGA/CebiaTech/2024/004]Internal Grant Agency of Tomas Bata University, (IGA/CebiaTech/2024/004
Innovation leadership and workplace innovative behaviour: An experimental investigation of leadership dynamics among it engineers in Vietnam
No full textIn recent decades, the economic context and competitiveness have required the development of new competencies and skills at all levels of management. The purpose of this study was to determine the level of development of engagement and knowledge sharing perceived by a group of employees and to assess their relationship to leadership and innovative behaviour. This was an experimental-type, intergroup comparison study that described how work engagement, knowledge sharing, leadership, and innovation behaviour of a group of 395 engineers at an IT company in Vietnam were manifested. The Innovation Leadership Scale (ILS-16) and the Workplace Innovation Behaviour Scale (WIB) were used to design this study. The results of this study could be an important contribution to the development of leadership empowerment programs and innovative work behaviour. Prospects for future research are to analyse other variables related to leadership and innovation behaviour, such as, for example, communication, to stimulate innovative behaviour of IT engineers, and to build a multiple regression model of such a relationship
Smart biopolymer scaffolds based on hyaluronic acid and carbonyl iron microparticles: 3D printing, magneto-responsive, and cytotoxicity study
Get PDFThis study deals with utilization of the hyaluronic acid (HA) and carbonyl iron (CI) microparticles to fabricate the magneto-responsive hydrogel scaffolds that can provide triggered functionality upon application of an external magnetic field. The various combinations of the HA and CI were investigated from the rheological and viscoelastic point of view to clearly show promising behavior in connection to 3D printing. Furthermore, the swelling capabilities with water diffusion kinetics were also elucidated. Magneto-responsive performance of bulk hydrogels and their noncytotoxic nature were investigated,, and all hydrogels showed cell viability in the range 75-85%. The 3D printing of such developed systems was successful, and fundamental characterization of the scaffolds morphology (SEM and CT) has been presented. The magnetic activity of the final scaffolds was confirmed at a very low magnetic field strength of 140 kA/m, and such a scaffold also provides very good biocompatibility with NIH/3T3 fibroblasts.Grantová Agentura České Republiky, GAČR, (22-33307S); Grantová Agentura České Republiky, GAČR; Ministerstvo Školství, Mládeže a Tělovýchovy, MŠMT, (RP/CPS/2024-28/003, CZ.02.2.69/0.0/0.0/19_073/0016941); Ministerstvo Školství, Mládeže a Tělovýchovy, MŠMTCzech Science Foundation [22-33307S]; Ministry of Education, Youth and Sports of the Czech Republic-DKRVO [RP/CPS/2024-28/003]; Project OP RDE Junior Grants of TBU in Zlin [CZ.02.2.69/0.0/0.0/19_073/0016941
Enhanced adsorption of anionic dyes onto NaOH modified green coffee waste biochar: characteristics and performance evaluation
No full textSynthetic dyes are resistant to self-degradation in aqueous systems that pose severe health hazards to marine life. This work focuses on the comparative adsorption evaluation of synthesized biochar derived from green coffee wastes (GCB) and NaOH-modified GCB (NaOH-GCB) for the removal of anionic dyes (Eriochrome Black T and Congo Red) in aqueous solution. The characterization results of NaOH-GCB indicate higher thermal stability, improved surface functionality with -OH groups, smaller particle size (from 2–15 µm decreased to 0.5–1 µm), higher pore volume (increase from 0.0027 to 0.003 cm3/g), and higher surface area (increase from 2.91 to 3.22 m2/g) which enhanced dye adsorption. The maximum adsorption capacity was attained using NaOH-GCB with values of 119.37 mg/g and 91.54 mg/g recorded for EBT and CR, respectively. For both adsorbents, the optimal removal for EBT and CR dyes was obtained at solution pH 2 and 7 due to electrostatic and hydrogen bonding interactions. CR had slightly lower removal than EBT due to its hydrophobic nature. Pseudo-second order and Redlich-Peterson were the most effective models in providing insights about the adsorption kinetics and isotherm, with the system being heterogeneous and involving multi-layer behavior. Additionally, thermodynamics elucidated the adsorption to be spontaneous and exothermic. After five reusability cycles, the NaOH-GCB indicated excellent performance of over 90% removal for both dyes. The results show that NaOH-GCB is potentially an economical adsorbent for efficient and effective remediation of dye-contaminated wastewater streams.Deanship of Scientific Research at Imam Abdulrahman Bin Faisal University, (IF-045-2022)Imam Abdulrahman Bin Faisal University [IF-045-2022]; Deanship of Scientific Research at Imam Abdulrahman Bin Faisal University, Dammam, KS
Structured singular value control with two-degree-of-freedom feedback loop factorization for oscillating plant with uncertain time delay and astatism
No full textApplication of Robust Control Toolbox for Time Delay Systems implemented in the Matlab system to the oscillating plant with uncertain time delay and astatism using the D-K iteration and algebraic approach. The algebraic approach combines the structured singular value, algebraic theory and algorithm of global optimization solving remaining issues in structured singular value framework. The algorithm for global optimization can be alternated with direct search methods such as Nelder-Mead simplex method giving solutions for problems with one local extreme. As a global optimization method, Differential Migration is used proving to be reliable in solving this type of problems. The D-K iteration represents a standard method in the structured singular value theory. The results obtained from the D-K iteration are compared with the algebraic approach.Ministerstvo Školství, Mládeže a Tělovýchovy, MŠMT, (LO1303, MSMT-7778/ 2014)Ministry of Education, Youth and Sports of the Czech Republic within the National Sustainability Programme [L01303 (MSMT-7778/2014)
Reduced-order H∞ loop-shaping controller design for nonlinear continuous-time HDD systems using Hankel-norm approximation
No full textThis paper presents the design and analysis of a reduced-order H∞ loop-shaping controller for nonlinear continuous-time Hard Disk Drive (HDD) systems. Utilizing the Hankel-norm approximation, we systematically reduce the controller order, aiming to preserve system performance while enhancing computational efficiency. MATLAB simulations are employed to model the HDD system dynamics and to evaluate the controller’s efficacy. Performance is quantitatively assessed using the Integral of Time multiplied by Absolute Error (ITAE) criterion. Results indicate that a 10th-order controller achieves a balanced trade-off between robust control, disturbance and noise attenuation, without significant performance loss. This approach demonstrates the potential for reduced-order controllers in complex HDD systems, offering a pathway towards practical implementation in high-precision industrial applications.Univerzita Tomáše Bati ve Zlíně, UTB, (IGA/CebiaTech/2024/001); Univerzita Tomáše Bati ve Zlíně, UTBInternal Grant Agency of the Tomas Bata University in Zlin [IGA/CebiaTech/2024/001
Plasma polymerization of pentane and hexane for antibacterial and biocompatible thin films
No full textAntibacterial polymeric coatings are deposited on polyethylene terephthalate (PET) films through atmospheric pressure plasma polymerization with pentane and hexane monomers. The process uses surface dielectric barrier discharge in nitrogen. XPS analysis reveals the formation of carbon- and nitrogen-containing films with oxygen incorporation from ambient air. Alkyl, hydroxyl, and amine groups contribute to the coatings' superhydrophilic properties post-treatment. Coating thickness varies with the monomer flow rate, with pentane yielding thicker coatings than hexane under identical conditions and deposition increasing linearly with the flow rate. Treated PET films show strong antibacterial activity against Staphylococcus Aureus and Escherichia coli, demonstrating plasma polymerization's potential in biomedical applications. Cytotoxicity, evaluated using the MTS assay, confirms biocompatibility.Gas Processing Center, College of Engineering, Qatar University; Ministerstvo Školství, Mládeže a Tělovýchovy, MŠMT, (RP/CPS/2024‐28/005, RP/CPS/2024‐28/002, RP/CPS/2024‐28/007); Ministerstvo Školství, Mládeže a Tělovýchovy, MŠMT; The Slovenian Research and Innovation Agency, ARRS, (L2‐3163); The Slovenian Research and Innovation Agency, ARR
The impact of the movement of labor between FDI and domestic firms on the labor productivity of domestic firms
No full textThe presence of foreign direct investment (FDI) firms generates a two-way labor movement, but most studies have only focused on one-way movement by examining either the movement from FDI firms to domestic firms or the movement from domestic firms to FDI firms. Therefore, this paper examines the impact of the two-way labor movement between FDI and domestic firms on the productivity of domestic firms in the case of Czechia from 2005 to 2019. By using system Generalized Moment Method (SGMM), we identify the positive impact of labor movement from FDI to domestic firms (labor horizontal) and vertical spillovers (labor backward and competition backward). However, we find that the movement from domestic firms to FDI firms does not have an impact on domestic firms. Nevertheless, the labor movement from domestic firms to FDI firms can enhance the positive impact of labor backward and competition backward on the productivity of domestic firms.Technology Agency of the Czech Republic, TACR, (TL03000319); Technology Agency of the Czech Republic, TACR; Univerzita Tomáše Bati ve Zlíně, UTB, (RO/2022/04); Univerzita Tomáše Bati ve Zlíně, UTBTechnology Agency of the Czech Republic [TL03000319]; Tomas Bata University in Zln [RO/2022/04
Critical entities resilience strengthening tools to small-scale disasters
Get PDFThe issue of critical infrastructure protection is still largely based on the concept of critical infrastructure resilience. However, it is already clear that this concept must be restructured, primarily due to the adoption of a new European Union directive that focuses on the resilience of critical entities that are owners or operators of individual critical infrastructures. This directive stipulates, among other things, an obligation for critical entities to provide unlimited services necessary for maintaining the most important functions of the state. For this reason, it is necessary to pay increased attention not only to strengthening the resilience of infrastructures, but also to the management processes of critical entities. Based on these facts, 161 tools suitable for strengthening the critical entities internal resilience against small-scale disasters are classified and defined in this article. These strengthening tools are defined for both entities and infrastructural resilience. The article further defines the environment and procedure for strengthening the critical entities internal resilience, thus expanding the application of the existing CERA method, which was originally designed for the purpose of assessing the critical entities resilience to small-scale disasters. The design part of the article also includes a presentation of an example of a practical application of the proposed procedure.Ministerstvo Vnitra České Republiky, (VK01030014, SP2025/088); Ministerstvo Vnitra České RepublikyMinistry of the Interior of the Czech Republic [VK01030014]; VSB - Technical University in Ostrava [SP2025/088