Tomas Bata University in Zlín
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Importance of heat transfer in membrane extrusion process involving flow-induced crystallization
Get PDFIn this work, a recently proposed viscoelastic non-isothermal extrusion film casting model, which accounts for flow-induced crystallization, was generalized by including heat transfer coefficient considering radiation, natural and forced convection. This variable heat transfer coefficient (HTC) based model was found to have the ability to predict the measured temperature, velocity, width and crystallization profile for process conditions typical for the production of polypropylene energy storage membranes. The difference between variable and constant HTC based models was investigated in more details by using systematic parametric study. The obtained results suggest that the use of the variable-HTC model should be preferred for polymer energy membrane production over the constant-HTC models, and flow-induced crystallization should always be included, otherwise the extrusion film casting model loses its ability to describe experimental reality. It is believed that the proposed model and the obtained results can help to understand the optimal process conditions for the production of polymer membranes for energy storage due to their use in rechargeable lithium-ion batteries and special energy storage.Grantová Agentura České Republiky, GA ČR, (21–09174S
Peer mediation as a means of eliminating conflict in the school environment
Get PDFAim. Peer mediation is a tool for the prevention of socio-pathological phenomena occurring in the school environment, is an opportunity to resolve conflicts through reconciliation. The paper focuses on the perception of the importance of peer mediation and on the presentation of the results of a questionnaire survey, the aim of which was to determine the respondents’ preferences after completion of the project process. Methods. The aim of the questionnaire survey was to determine how pupils and students perceive peer mediation. The survey sample consisted of selected pupils from 6 primary schools aged 10 to 15 years and students from 6 secondary schools aged 15 to 18 years. The questionnaire was completed at the beginning (year 2020-N = 189, including 90 primary school pupils) and end of the project implementation (year 2021-N = 124, including 56 primary school pupils). Results. The responses in the entry and exit questionnaires, the respondents declared after participating in the project process an increase in their experience with peer mediation, expressed an interest in becoming peer mediators and resolving personal and school conflicts through peer mediation. Conclusion. Peer mediation engages pupils in a common dialogue to resolve conflicts at school through reconciliation and is a suitable way to prevent undesira-ble social phenomena in the school environment. The results of the research showed that respondents preferred peer mediation and perceived it as an appropriate form of conflict resolution in the school environment
Investigation on mechanical, gas barrier, and biodegradation properties of graphene oxide reinforced bovine trimmings derived collagen biocomposite
Get PDFNow-a-days, let out a huge number of bovine trimmings based solid waste from tanneries has caused significant environmental concerns. To overcome this problem, this study emphasizes on bovine trimmings derived collagen based high-performance composite with graphene oxide (Col-GO) by using solvent evaporation method. The Col-GO composite film formation was governed by plasticization with glycerol, crosslinking reaction of collagen chain; and H-bonding interaction between GO and collagen functional groups. The Col-GO composite films were characterized by Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and contact angle measurements. FTIR and TGA results indicate that interfacial H-bonding interaction between GO with collagen, and thermal stability of Col-GO composites film. Contact angle results indicate that hydrophobicity of Col-GO films was significantly enhanced compared to pure collagen film. The SEM analysis results indicate the homogeneous integration of GO in the Col-GO composite film. The composite film exhibits improvement in tensile strength and Young's modulus (YM) by 45% and 33% respectively. The water and gas barrier properties of the composite film improved by 47.4%, 66.57%, and 87.34%, respectively compared to pure collagen film. The Col-GO composite film showed excellent biodegradation in the soil burial test, degrading 79.47% in 42 days. The potential of the biodegraded Col-GO composite sample as a biofertilizer has been investigated by cultivating Spinacia oleracea seeds. The Col-GO composite film might be a very promising bio-compostable flexible and sustainable packaging film alternative to plastic packaging made from oil
Improving the performance of effort estimation in terms of function point analysis by balancing datasets
No full textThis research proposes an approach to improve the performance of effort estimation based on the balancing of each group for categorical variables. The proposed model is based on function point analysis, Industry Sector, and deep learning. The Pytorch library is used to build the deep learning model with the dataset ISBSG (release 2020). The accuracy of our model is compared with that of the Adj-Effort approach. We adopt the prediction level at 0.3, Mean Absolute Error, Mean Balanced Relative Error, Mean Inverted Balanced Relative Error, and Standardised Accuracy as criteria for validation. The findings demonstrate that our proposed model outweighs the unbalanced and Adj-Effort approaches. © 2023, The Author(s), under exclusive license to Springer Nature Switzerland AG.IGA/CebiaTech/2022/00
Comparison of stabilization with P/I-delayed controllers for second-order systems using built-in MATLAB heuristic optimization methods
No full textIn control theory, optimization is a process that makes some system behavior as likelihood, functional, or practical as possible (depending on the design requirements). From a mathematical point of view, optimization is a way to find the minimum or maximum of the mathematical function by which the system is described. Moreover, if there is a time delay in the feedback loops inside a controlled system, the system has an infinite spectrum – infinitely many roots (poles); this degrades the control's quality, especially in terms of stability, robustness, and oscillation response. For these reasons, it is necessary to optimize the system transient response. This paper will compare selected heuristic methods of optimization of linear-time invariant (LTI) systems with time delay in an integral part of the P/I-delayed controller. Some examples are chosen as benchmarks to verify the effectiveness of the optimization. In future research, we would like to focus on implementing selected modern optimization algorithms for solving non-smooth, non-convex, and non-Lipschitz optimization problems. © 2023, The Author(s), under exclusive license to Springer Nature Switzerland AG.IGA/FAI/2022/00
Current state-of-the-art review of nanotechnology-based therapeutics for viral pandemics: Special attention to COVID-19
Get PDFOver the past two centuries, most pandemics have been caused by zoonotic RNA viruses with high mutation, infection, and transmission rates. Due to the importance of understanding the viruses' role in establishing the latest outbreak pandemics, we briefly discuss their etiology, symptomatology, and epidemiology and then pay close attention to the latest chronic communicable disease, SARS-CoV-2. To date, there are no generally proven effective techniques in the diagnosis, treatment, and spread strategy of viral diseases, so there is a profound need to discover efficient technologies to address these issues. Nanotechnology can be a promising approach for designing more functional and potent therapeutics against coronavirus disease 2019 (COVID-19) and other viral diseases. Moreover, this review intends to summarize examples of nanostructures that play a role in preventing, diagnosing, and treating COVID-19 and be a comprehensive and helpful review by covering notable and vital applications of nanotechnology-based strategies for improving health and environmental sanitation.RP/CPS/2022/005; Ministerstvo Školství, Mládeže a Tělovýchovy, MŠM
Production planning process based on the work psychology of a collaborative workplace with humans and robots
Get PDFThis study focuses on discerning how economics, as it pertains to work psychology, is lent a new perspective by the compatibility of humans and robots cooperating in the manufacturing sector. The stability of production plans, flexibility of the organizations, and the management of production constitute the basis for such analysis. In this context, initial findings revealed that steady performance by an individual was significantly influenced by a production plan, while the cycle and lead times in place fundamentally affected the behaviour of employees. Observations were made over five years of 200 workers at 100 manufacturers. Times given over to operations and cycles, and throughput, were primarily defined by the technical cycle of the robot. The secondary element of production planning was the employee, whose operator cycle time was informed by that of the robot. The authors set out to deduce which key factors altered the work psychology in situ in manufacturing environments where collaboration occurred between humans and robots. Prerequisites for optimal psychological conditions were identified (the cooperating human, production planner, collaborative workplace, standardized durations of complete tasks, distance between the worker and robot, and data analytics of production flow). Ensuring circumstances are optimal in terms of work psychology is essential to raising productivity and employee performance. Results showed that the operator was directly dependent on the robot in relation to mutual, continuous production flow. A model of production plan stability was devised, informed by the dependence of specific parameters of the planning model. Research was conducted on the reliance of selected parameters, leading to establishment of prerequisites for an optimal work psychology setting in enterprises with such a collaborative structure
Localizing origin of foreign investments in the Czech Republic, or when is a foreigner one of us
Get PDFPromotion of foreign investment is a well-established practice in many countries with an inadequate capital base, and the benefits of this type of investment, particularly in the form of positive spillover effects on the domestic economic environment, have been repeatedly confirmed by numerous studies. However, still not enough attention is paid to the definition and actual content of the word "foreign" in the phrase foreign direct investment in the domestic environment. This methodological essay attempts to fill that deficit and, using the concepts of foreign and domestic roundabout investment, to propose a categorization of capital investment which would take into account both the actual origin of the investor and the actual place of production or provision of the service, as well as the perception of the product or service as foreign or local. The resulting categorisation matrix is then populated with concrete examples from Czech practice and commented on in detail. The matrix can close the gap in the current Czech literature, which concentrates on the terms "foreign" or "domestic" more than on their very substance and their material meaning
The relationship between destination image and destination safety during technological and social changes COVID-19 pandemic
Get PDFThis study aimed to assess the relationship between safety perceptions and destination image in the Central European region during the technological and social environment change brought about by the COVID-19 pandemic. The study sample consisted of respondents from three Central European countries, namely, the Czech Republic, Hungary, and Slovakia. The quantile regression analysis was used to analyze the relationship between the image of the destination and its perceived safety. The results showed that concerns about the safety of the tourism environment could be negatively associated with the image of the infrastructure in Hungary and Slovakia, with value for money in the three countries, and with images of enjoyment in Slovakia. Higher levels of destination safety may be associated with a more positive destination image, with health, facilities and services being the most important dimensions of perceived safety, because of the pandemic. This study contributes to the knowledge of the concept of destination images and the development of tourism.Vedecká Grantová Agentúra MŠVVaŠ SR a SAV, VEGA: 1/0590/22; Univerzita Tomáše Bati ve Zlíně: FSR-S/2020/FaME/001Tomas Bata University in Zlin [FSR-S/2020/FaME/001]; Scientific Grant Agency of the Ministry of Education, Science, Research, and Sport of the Slovak Republic; Slovak Academy Science
Defence systems against drone attacks
No full textLarge European airports have now been forced to close several times due to the disruption of their protected area by drones. The biggest incident in terms of damage and restrictions clearly includes the attack of 19 and 21 December 2018 on one of the largest airports in Europe, London - Gatwick. All air traffic was interrupted, and flights were canceled and postponed. It was only a matter of time before drone technology was used by terrorist organizations and other criminals for their attacks. The article discusses the dangers that drones can cause. It describes the various basic categories of drones, their historical development, and the beginnings of the misuse of drones by terrorist organizations. The types currently used by the armed forces in the war in Ukraine are also mentioned. Furthermore, the article deals with systems that aim to eliminate this threat and which are available to companies and individuals financially. Thus, drone defense systems were selected and compared with a detailed description of their detection and destruction methods. The article concludes that a modern anti-drone defense for soft targets has already been developed and a set of recommendations for their combination and implementation follows.Univerzita Tomáše Bati ve Zlíně: IGA / FAI / 2022/00