Tomas Bata University in Zlín
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Personality traits and business environment for entrepreneurial motivation
Get PDFThe influences of personality traits and business barriers on entrepreneurial behaviour have been studied by numerous researchers. However, the mechanisms by which changes in institutional contexts and personality traits affect individuals' entrepreneurial motivation have not received enough attention from researchers. This paper aims to fill this gap in the literature by examining the joint effects of personality traits and business barriers on one's motivation to engage in entrepreneurial activity. A structured questionnaire was developed to capture the above linkages. To measure the latent variables, factor and reliability analyses were utilised. To examine the relationships, a regression analysis was performed on a unique dataset of respondents from three counties: Czechia, Hungary, and Serbia. The results show that personality traits positively influence motivation towards entrepreneurship. Furthermore, external barriers (ecological and technological issues), and infrastructure factors positively affect entrepreneurial motivation. From an academic viewpoint, personality traits and motivation to engage in entrepreneurial activity can be nourished by education, highlighting the role of universities in this regard. Our paper's findings should trigger the interest of policymakers who aim to introduce new instruments or change the existing ones (designing policies) to boost entrepreneurship.International Visegrad Fund, IVF: 21820267International Visegrad Fund; [21820267
Marketing effort within the newsvendor problem framework: A systematic review and extensions of demand-effort and cost-effort formulations
Get PDFThis study deals with a generalization of the newsvendor problem with marketing efforts. Combining inventory and marketing decisions is currently a topic that has been widely studied. Various formulations of marketing efforts and their costs have been applied in the literature. Therefore, a systematic review was performed to identify existing formulations, especially those that deal with mathematical modeling and optimization. The findings observed on a wide set of marketing effort formulations are summarized, generalized, and applied in the newsvendor problem framework. It was found that the optimal marketing effort decision does not depend on the uncertainty involved in the model for the additive demand case under commonly used assumptions. Optimal marketing is equal to its deterministic equivalent, contrary to the multiplicative form, where the decision directly depends on uncertainty. Formulations of the demand-effort response function and the cost of marketing effort are generalized (to concave and convex functions, respectively) and extended to an S-shaped demand-effort response function. Assumptions and theorems that guarantee the uniqueness of optimal marketing efforts are established. Finally, the effects of price and cost parameter changes on optimal marketing effort decisions were analyzed.Grantová Agentura České Republiky, GA ČR; Univerzita Tomáše Bati ve Zlíně: GA 20-00091YTomas Bata University [FSR FORD 5-6/2021-23/FAI/002, 20-00091Y]; Czech ScienceFoundatio
Experimental analysis of photovoltaic thermal system assisted with nanofluids for efficient electrical performance and hydrogen production through electrolysis
Get PDFIn this study the influence of the nanofluid in the photovoltaic thermal system (PVT) has been examined experimentally. The nanoparticles zinc oxide (ZnO) dispersed in the base fluid water at the concentration of 0.25 %wt. A series of experimental tests were conducted between 9:00 A.M. to 16:00 P.M. ZnO nanofluids passed through the PVT panel at various mass flow rates. To increase the thermal efficiency and performance of the PVT, instead of using plain water, nanofluids were introduced. The parameters such as output power, surface temperature, fluid outlet temperature, thermal efficiency, and electrical efficiency were examined at the different mass flow rates such as 0.008 kg/s, 0.010 kg/s, and 0.012 kg/s. Added to above, the proposed photovoltaic thermal system was also assisted in producing hydrogen by electrolysis process. Polymer electrolyte membrane (PEM) has been used to generate the hydrogen via electrolysis. With the use of nanofluids, the electrical efficiency and thermal efficiency were increased owing to the reduction in the cell temperature. Introduction of the nanofluids at the optimal mass flow rate helps the panel to produce higher electrical output. The hydrogen yield rate was also increased by the use of nano -fluids. Among the different mass flow rate, 0.012 kg/s reported maximum thermal efficiency of 33.4% with the hydrogen production rate of 17.4 ml/min. Based on the extensive observed results procured, photovoltaic thermal systems can be a promising candidate for the pro-duction of hydrogen using PEM electrolyzer.Natural Science Foundation of Jiangsu Province: BK20200775Natural Science Foundation of Jiangsu Province [BK20200775]; Van Lang Universit
Precision and dimensional stability of bonded joints of carbon-fibre-reinforced polymers parts
Get PDFThis article aims to investigate the accuracy and dimensional stability of bonded metal and CFRP (Carbon Fibre Reinforced Plastic) adherends. The motivation behind this study was to assess the suitability of CFRP for optical devices through the evaluation of precision bonding technology. A binocular was selected as a reference optical device. A technological sample was designed, with required total runout of key dimensions 0.05 mm. The sample underwent testing according to ISO 9022-1. The total runout was evaluated after production and environmental tests. Eight out of 15 samples were turned after gluing due to insufficient accuracy. None of the turned samples exceeded the total runout deviation of 0.01 mm, and the average value of the maximal deviation was 0.0041 mm. The noncalibrated samples performed significantly worse with the average value of the maximal deviation of 0.0164 mm. The measurements during the climatic tests showed that the largest deviation (on average 77.6% of the maximum achieved deviation) occurs at the first temperature loading. Subsequent temperature cycles caused lower deviations. The results highlight the significance of addressing deformations resulting from adhesive volume shrinkage-induced stress as a crucial factor in precision bonding technology.Ministry of Defence of Czech Republic; Ministerstvo Školství, Mládeže a Tělovýchovy, MŠMTMinistry of Education, Youth and Sports (MEYS, MSMT in Czech) [FV 22-10]; Project for the Development of the Organ-ization "VAROPS (DZRO VAROPS) Military autonomous and robotic assets" by the Ministry of Defence of Czech Republi
Reactive laser ablation in acetone towards phase-controlled nonequilibrium Iron- and Nickel-Bi2O3 nanoalloys
No full textThe ongoing development of new nanocatalysts is powered by the ambitious vision of finely controlling their structure while ensuring their remarkable features in heterogeneous chemical reactions. Especially in processes where the catalysts must be recycled, the union of catalytic activity and magnetic motility belongs among the most desirable characteristics. In recent years, the effort to optimize this synergy in photocatalysis has led to a focus on creating bismuth-based bimetallic nanoparticles (NPs), also known as nanoalloys. Nevertheless, the optimization of their properties and sustainable development still need to be well-considered. Therefore, we herein present for the first time the synthesis of phase-controlled nickel-Bi2O3 and iron-Bi2O3 NPs, whose non-equilibrium composition is provided by the sustainable method known as reactive laser ablation in liquids (RLAL), resulting in a bandgap modification in both types of magnetic nanoalloys. In addition, the profound analyses of RLAL introduce the first report about the limitations and new perspectives of this relatively novel nanotechnology, in which the usage of chemically similar magnetic foils (iron and nickel) leads to extensively different NPs compositions and properties. Overall, these findings provide a groundwork for understanding the formation of non-equilibrium nanoalloys representing a rising generation of nanocatalysts.DKRVO, (RP/CPS/2022/007); Ministerstvo Školství, Mládeže a Tělovýchovy, MŠMT, (LM2023066); Technická Univerzita v Liberci, (SGS-2022-3008); Silesian University of Technology, SUT, (10/100/RGJ23/0055, 52210829
Biodegradable zinc-based materials with a polymer coating designed for biomedical applications
Get PDFOver the last decades, biodegradable metals have gained popularity for biomedical applications due to their ability to assist in tissue healing. These materials degrade in vivo, while the corrosion products formed are either absorbed or excreted by the body, and no further surgical intervention is required for removal. Intensive research has been carried out mainly on degradable biomaterials based on Mg and Fe. In recent years, zinc-based degradable biomaterials have been explored by the biomedical community for their intrinsic physiological relevance, desirable biocompatibility, intermediate degradation rate, tuneable mechanical properties and pro-regeneration properties. Since pure Zn does not exhibit sufficient mechanical properties for orthopedic applications, various Zn alloys with better properties are being developed. In this work, the combined effect of minor Fe addition to Zn and a polyethyleneglycol (PEG) coating on the surface morphology, degradation, cytotoxicity and mechanical properties of Zn-based materials was studied. There are several studies regarding the influence of the production of Zn alloys, but the effect of polymer coating on the properties of Zn-based materials has not been reported yet. A positive effect of Fe addition and polymer coating on the degradation rate and mechanical properties was observed. However, a reduction in biocompatibility was also detected.International Visegrad Fund, IVF, (22310096, VEGA02/00006/22, VVGS‐2023‐2550); Tomas Bata University in Zlin, TBU, (CZ.02.2.69/0.0/0.0/16_027/0008464, CZ.02.2.69/0.0/0.0/18_053/0017879); Agentúra na Podporu Výskumu a Vývoja, APVV, (APVV‐20‐0278)Slovak Research and Development Agency; Operational Programme for Research, Development and Education; European Union [CZ.02.2.69/0.0/0.0/16_027/0008464, CZ.02.2.69/0.0/0.0/18_053/0017879]; International Visegrad Fund [22310096]; Slovak Grant Agency [VEGA02/00006/22]; P. J. Safarik University [VVGS-2023-2550
Transformation into 4PL: The case of local logistics service providers in Vietnam
Get PDFFor a few decades, a new model of logistics service providers (LSP) has appeared and played the role of integrating all operations of the supply chain. This model is known as a logistics integrator, or fourth party logistics (4PL). 4PL has emerged as an ideal configuration for enterprises around the world to effectively utilize their resources and obtain cost reduction across the supply chain. With increasing competition among enterprises, customers' requirements for complicated services, and global supply chain management, the limitations of inbound services from LSPs have become obstacles to their development. As a result, transformation into 4PL is inevitable for LSPs in the global logistics market. This paper aims to analyze the role, characteristics, and benefits of 4PL. A model for transformation into 4PL for local LSPs in Vietnam is constructed to identify impacting factors. The results point out six factors influencing the transformation process, as well as three important capabilities of 4PL.IGA/FaME/2022/006FaME UTB in Zlin [IGA/FaME/2022/006
Study of mechanical properties of epoxy/graphene and epoxy/halloysite nanocomposites
Get PDFThis article aimed to compare various mechanical properties of epoxy/graphene and epoxy/halloysite nanocomposites. Graphene nanoplatelets (GnPs) and halloysite nanotubes (HNTs) were used as fillers at different concentrations. The studied fillers were dispersed in the epoxy resin matrices. Elastic-plastic mechanical behavior modulation was observed utilizing the fillers' nanoparticles and carboxyl-terminated butadiene-acrylonitrile copolymer rubber-modified epoxy resin. The hypothesis of the possible preceding inter-particle gliding of the individual GnPs in the complex resin nanocomposite matrix during mechanical testings was also confirmed. Increased ductility (elongation at break increased from 0.33 mm [neat matrix] to 0.46 mm [1 wt% GnPs] [39% increase]) and plasticity of the GnP nanocomposite samples were observed. In contrast, the decreasing mechanical stiffness as reflected in the decreased Young's modulus of elasticity (from 3.4 to 2.7 GPa [20% decrease]) was found for the epoxy/HNT nanocomposites. The obtained dynamic stiffness of the investigated nanocomposites confirmed the complexity of the mechanical response of the studied material systems as a combination of the ductile and brittle phenomena.CZ.02.1.01/0.0/0.0/16_019/0000867; Tomas Bata University in Zlin, TBU: IGA/FT/2022/005, IGA/FT/2023/007; Univerzita Palackého v Olomouci: IGA_PrF_2022_020, IGA_PrF_2023_024European Regional Development Fund in the Research Centre of Advanced Mechatronic Systems project [CZ.02.1.01/0.0/0.0/16_019/0000867]; Palacky University in Olomouc [IGA_PrF_2022_020, IGA_PrF_2023_024]; Tomas Bata University in Zlin [IGA/FT/2022/005, IGA/FT/2023/007]; Fischer scholarship of the Faculty of Science, Palacky University in Olomou
Engineering of inhalable nano-in-microparticles for co-delivery of small molecules and miRNAs
Get PDFIn this study, novel Trojan particles were engineered for direct delivery of doxorubicin (DOX) and miR-34a as model drugs to the lungs to raise local drug concentration, decrease pulmonary clearance, increase lung drug deposition, reduce systemic side effects, and overcome multi-drug resistance. For this purpose, targeted polyelectrolyte nanoparticles (tPENs) developed with layer-by-layer polymers (i.e., chitosan, dextran sulfate, and mannose-g-polyethyleneimine) were spray dried into a multiple-excipient (i.e., chitosan, leucine, and mannitol). The resulting nanoparticles were first characterized in terms of size, morphology, in vitro DOX release, cellular internalization, and in vitro cytotoxicity. tPENs showed comparable cellular uptake levels to PENs in A549 cells and no significant cytotoxicity on their metabolic activity. Co-loaded DOX/miR-34a showed a greater cytotoxicity effect than DOX-loaded tPENs and free drugs, which was confirmed by Actin staining. Thereafter, nano-in-microparticles were studied through size, morphology, aerosolization efficiency, residual moisture content, and in vitro DOX release. It was demonstrated that tPENs were successfully incorporated into microspheres with adequate emitted dose and fine particle fraction but low mass median aerodynamic diameter for deposition into the deep lung. The dry powder formulations also demonstrated a sustained DOX release at both pH values of 6.8 and 7.4.Tomas Bata University in Zlin, TBU: RP/CPS/2022/005; Grantová Agentura České Republiky, GA ČR: GA 20-27653
Composite based on PLA with improved shape stability under high-temperature conditions
No full textComposite materials based on PLA have been studied in depth for many applications, including food packaging. This manuscript describes extensive research conducted on a biodegradable polymer (PLA), inorganic filler (CaCO3), and polyester-based plasticizer (PEP, based on a copolymer of low-molecular-weight PLA and PEG) prepared under semi-industrial conditions, as applicable for the packaging of hot food. The properties of the composite were achieved by post-processing annealing, notably its thermal stability, thereby permitting contact of the material with hot food. The manner of processing was deemed suitable for deployment at an industrial scale, moreover, the thermal stability of the final product endured, evidencing its applicability for such packaging. Change in the morphology of the structure of the composite material depended on the composition and annealing process, as detailed herein. The effect of the post-production thermal annealing on the molecular weight of samples was studied using the gel permeation chromatography. The thermal properties of the composites were investigated by differential scanning calorimetry, dynamic mechanical analysis, and thermogravimetric analysis. The crystallinity was assessed using X-ray diffraction technique, while mechanical behavior was tested in relation to the given tensile properties, shape stability at high temperature, and permeability by the transmission rates of gas/water vapor.Technology Agency of the Czech Republic, TACR: TH02020836; Ministerstvo Školství, Mládeže a Tělovýchovy, MŠMT: 8JPL19031, RP/CPS/2022/00