Tomas Bata University in Zlín
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Interested in threats: Exploring how emotional interest shapes security studies scholarship
No full textSecurity studies scholars are, by definition, interested in threats. But how does interest shape their knowledge production? We draw on contemporary psychological literature to theorize interest as an emotion and use abductive logic combined with illustrative examples to show how such theorization relates to knowledge-generating dynamics in security studies scholarship. Emotional interest explains how real-world affairs (fail to) become subjects of scholarly inquiry, why scholars persist in studying specific subjects despite the changes in real-world affairs and how that study changes them, and how prior scholarly interests influence subsequent development of other interests. Our findings address a theoretical gap in the existing security studies scholarship and present opportunities for enhancing personal and collective research and teaching practices. Los acad & eacute;micos del campo de los estudios de seguridad tienen, por definici & oacute;n, inter & eacute;s en estudiar las amenazas. & iquest;Pero c & oacute;mo influye este inter & eacute;s sobre su producci & oacute;n de conocimiento? Partimos de la literatura contempor & aacute;nea sobre psicolog & iacute;a con el fin de teorizar el inter & eacute;s como una emoci & oacute;n. Tambi & eacute;n utilizamos la l & oacute;gica abductiva combinada con ejemplos ilustrativos con el fin de mostrar c & oacute;mo dicha teorizaci & oacute;n se relaciona con la din & aacute;mica generadora de conocimiento en el campo acad & eacute;mico de los estudios de seguridad. El inter & eacute;s emocional explica: c & oacute;mo los asuntos del mundo real (no logran) convertirse en sujetos de investigaci & oacute;n acad & eacute;mica, por qu & eacute; los acad & eacute;micos persisten en estudiar temas espec & iacute;ficos a pesar de los cambios en los asuntos del mundo real y c & oacute;mo ese estudio los cambia, y c & oacute;mo los intereses acad & eacute;micos previos influyen sobre el desarrollo posterior de otros intereses. Nuestras conclusiones abordan un vac & iacute;o te & oacute;rico en la literatura acad & eacute;mica existente en el campo de los estudios de seguridad y presentan oportunidades para mejorar la investigaci & oacute;n, tanto personal como colectiva, y las pr & aacute;cticas docentes. Par d & eacute;finition, les chercheurs en & eacute;tudes de s & eacute;curit & eacute; s'int & eacute;ressent aux menaces. Mais comment cet int & eacute;r & ecirc;t fa & ccedil;onne-t-il leur production de connaissances ? Nous nous fondons sur la litt & eacute;rature psychologique contemporaine pour th & eacute;oriser l'int & eacute;r & ecirc;t telle une & eacute;motion et employons l'abduction combin & eacute;e & agrave; des exemples d'illustration pour montrer le lien entre cette th & eacute;orisation et les dynamiques de production de connaissances dans la recherche en & eacute;tudes de s & eacute;curit & eacute;. L'int & eacute;r & ecirc;t empirique explique pourquoi les affaires du monde r & eacute;el deviennent des sujets d'& eacute;tude acad & eacute;mique (ou pas), pourquoi les chercheurs continuent d'& eacute;tudier certains sujets malgr & eacute; les modifications du monde r & eacute;el et comment cette & eacute;tude les modifie eux, et enfin, comment des int & eacute;r & ecirc;ts acad & eacute;miques ant & eacute;rieurs influencent le d & eacute;veloppement ult & eacute;rieur d'autres int & eacute;r & ecirc;ts. Nos conclusions viennent combler une lacune th & eacute;orique dans la recherche existante en & eacute;tudes de s & eacute;curit & eacute; tout en offrant des possibilit & eacute;s de renforcement des recherches et pratiques d'enseignement personnelles et collectives.Tomas Bata University [RVO/FLKR/2024/02]; Program "Creativity, Inteligence & Talent pro Zlinsky kraj
Enhancing supercapacitor energy density via KMnO4-activated apple waste-derived carbon and aqueous trifluoroacetic acid electrolyte
No full textThe conversion of biowaste into cost-effective porous carbons for electrode materials represents a promising strategy for sustainable energy storage. However, such materials often suffer from low specific capacitance and energy density. In this study, activated carbons (ACs) were synthesized from apple waste (AW) through chemical activation with potassium permanganate (KMnO4), followed by carbonization at 650–800 °C. The as-prepared AW AW-derived ACs were characterized and evaluated in both three-electrode and symmetric supercapacitor configurations across different electrolytes. The resulting AW-derived carbons exhibited a large specific surface area (>1000 m2 g−1) and demonstrated good electrochemical performance, with a specific capacitance of 360 F g−1 at 1 A g−1. The AW-based electrode using a trifluoroacetic acid (TFA) electrolyte exhibited a wide potential window (−0.5 V–1 V vs. Calomel), outperforming traditional electrolytes like KOH and H2SO4. The symmetric device had exceptional cycling stability, maintaining 93.5 % of its initial capacitance after 5000 cycles, and attained an energy density of 14.5 Wh kg−1 alongside a power density of 345.3 W kg−1. These results show the viability of biowaste-derived carbons as efficient, sustainable materials for next-generation supercapacitors.The authors acknowledge the financial support provided by Internal Grant Agency (IGA) project IGA/CPS/2024/005 and IGA/CPS/2025/007 of the Center of Polymer Systems at the Tomas Bata University in Zlin . The research was also supported by the Ministry of Education , Youth and Sports of the Czech Republic\u2013DKRVO (RP/CPS/2024-28/005).Internal Grant Agency (IGA) of the Center of Polymer Systems at the Tomas Bata University in Zlin [IGA/CPS/2024/005, IGA/CPS/2025/007]; Ministry of Education, Youth and Sports of the Czech Republic-DKRVO [RP/CPS/2024-28/005
Digesting the truth: The role of energy justice in perception of anaerobic digestion plants in Central Europe rural space
No full textAnaerobic digestion (AD) plants are integral to the circular economy, yet they are often the subject of significant local controversy, particularly during operation. This contrasts sharply with the acceptance trajectories of other renewables and poses a significant barrier to their broader utilization. To explore the roots of this phenomenon, the present study focused on the significance of selected particular factors related to energy justice. Based on a questionnaire survey (N = 446) in four rural communities in the Czech Republic and Slovakia where AD plants are located, we evaluated how procedural, distributive, and recognition justice shape residents' perceptions of the existence of anaerobic digestion plants in Central Europe conditions. The results of ordinal logistic regression show that procedural justice is the most critical factor for positive perception. Specifically, the perceived opportunity for residents to participate in planning and the operator's responsiveness to subsequent concerns were identified as the most significant predictors of acceptance. Our findings highlight that the continuous improvement of the plant operator's relations with other local groups (municipality, residents, and local business entities) is not an option but a fundamental prerequisite for achieving energy justice in biogas utilization and the integration of AD plants as vital renewable energy sources.This article was developed within the project VEGA 1/0768/24 \u201CMultiscale assessment of spatial variability of social-economic population stratification\u201D. This article has been produced with the financial support of the European Union under the REFRESH \u2013 Research Excellence For REgion Sustainability and High-tech Industries project number CZ.10.03.01/00/22_003/0000048 via the Operational Programme Just Transition. We also thank the three anonymous reviewers for their effort and thoughtful comments, which significantly contributed to improving the quality and clarity of the paper. Finally, we would like to express our sincere gratitude to the editor assigned to our paper for his valuable advice and helpful guidance throughout the submission process.VEGA [1/0768/24]; European Union under the REFRESH-Research Excellence For REgion Sustainability and High-tech Industries [CZ.10.03.01/00/22_003/0000048
Reproducibility assessment of zirconia-based ceramics fabricated out of nanopowders by electroconsolidation method
Get PDFFeatured Application: the results of this work can be useful in any application of zirconia-based ceramics, especially when considering various sintering methods. The repeatability of the material properties is required to ensure the proper performance of the engineered systems that are constructed using these materials. In this paper, an analysis of the sintered ceria-stabilized zirconia is presented. This material exhibited high mechanical properties, due to the mechanism of strengthening via phase transition. The reproducibility was assessed for the material made out of a starting powder produced by fluoride salt precipitation. To fabricate specimens, a novel electroconsolidation method was used, ensuring a high heating rate, relatively low sintering temperatures, and short holding time. Weibull analysis was performed considering the bending strength of specimens and their microhardness. The obtained values of both shape parameter m and scale parameter σ0 indicated that the ZrO2 stabilized with 5 wt.% CeO2 samples exhibited low variability of strength and hardness. The experimental evidence and statistical analysis reveal an influence of the m-phase, which has lower symmetry and therefore its addition makes ceramic weaker and softer. Furthermore, its progressive replacement by the t-phase, which has higher symmetry, makes ceramic both harder and stronger. Reducing the mol% increases the risk of the appearance of the highest addition of the monoclinic phase; increasing it is unfavorable from the point of view of the sintering process. Statistical and manufacturing evidence suggests that the choice of 5%/mol is optimal.Narodowe Centrum Nauki, NCN, (2022/47/B/ST5/01041); Narodowe Centrum Nauki, NCN; Centre of Polymer Systems Development, (RP/CPS/2024-28/007)National Science Centre, Poland [2022/47/B/ST5/01041]; Centre of Polymer Systems Development Project [RP/CPS/2024-28/007
Flow-induced reduction of the monomeric friction coefficient using a branched environment in linear isotactic polypropylene melt
Get PDFIn this work, the effect of the stretch Weissenberg number, WiR, on the monomeric friction coefficient is investigated for three entangled linear isotactic polypropylenes (L-PP) and three entangled long-chain branched polypropylene miscible blends (LCB-PP), both groups of polymer melts with a comparable range of the number of Kuhn segments of the whole chain, the number of Kuhn segments between entanglements, the number of entanglements per chain, and the polydispersity index, via free volume measurements using the Williams-Landel-Ferry equation and temperature-dependent high-strain rate rheology (covering the extensional strain rate range of 2 × 104 1/s to 2 × 106 1/s at a Hencky strain of 6.8) via entrance pressure drop measurements in an abrupt contraction flow using the Gibson method. The ratio of the equilibrium monomeric friction coefficient defined by Doi and Edwards, ζeq, to the monomeric friction coefficient for fully aligned chains due to strong uniaxial extensional flow, ζaligned, was found to increase in the following order: L-PPs (5.234 ± 0.8489) < 10 wt % LCB-PP blend 64k (6.249 ± 0.3950) < 20 wt % LCB-PP blend 70k (8.061 ± 0.1851) < 30 wt % LCB-PP blend 78k (11.104 ± 0.8995). The presence of a high-molecular-weight branched environment in low-molecular-weight linear PPs caused a more intense decrease in the monomeric friction coefficient (due to the increased free volume indicating a higher coalignment ability of the macromolecules in the LCB-PP blends compared to that of pure linear PP macromolecules), leading to a decrease in the Trouton ratio at WiR, in which the polymer chains become fully aligned.Grantová Agentura České Republiky, GACR, (24-11442S); Grantová Agentura České Republiky, GACRGrantov? Agentura Cesk? Republiky [24-11442S]; Grant Agency of the Czech Republic; Netzsch Gerateba
Assessing the moderating role of technological innovation on food security in poverty reduction within the Visegrad region
Get PDFThe global shift for sustainable development has elicited nations and governments to develop policies to safeguard humankind and the environment. The investigation premised on the poverty reduction within the Visegrad communities (Czech Republic, Hungary, Poland, and Slovakia). The evaluation employed panel data from 2000 to 2022 on the variables of poverty (POV), food security (FOD), foreign direct investment inflow (FDI), economic progress (ECP), population growth (POG), inflation growth (ING), and technological innovation (TIN). Various preliminary assessment of cross-sectional dependence, unit root, and cointegration was evaluated to ensure data reliability and validity. The econometric approach of Cross-Sectional Augmented Distributed Lag (CS-ARDL) model was adopted to study the short- and long-term affiliation. The findings revealed that (a) FOD, FDI, POG, and TIN had a material influence on poverty reduction. (b) However, ECP and ING appreciation poverty rate within the Visegrad region. (c) Again, there was a serial moderating effect of TIN on the affiliation between FOD and POV in the Visegrad region. Furthermore, the Dumitrescu-Hurlin causality test indicated a unidirectional nexus between FOD, FDI, POG, and TIN with POV reduction. While a bidirectional was established on ECP and ING with POV reduction. The outcome serves as a policy and practical supplement to government and institutional agencies in charge of poverty mitigation. The outcome recommend that government should invest in technological innovation to improve food security and poverty reduction to achieve the SDG1 by 2030
Prediction of creep behavior in short fiber reinforced polymer matrix composites using an elementary volume approach
Get PDFCreep behavior of short glass fiber reinforced poly(butylene terephthalate) (SFRC PBT) composites was analyzed using plates processed by injection molding and push–pull processing, with fiber contents of 0, 20, and 30 wt%. Tensile test bars were extracted parallelly and perpendicularly to the flow direction to assess short-term mechanical properties, fiber length distribution, and orientation. An elementary volume approach was used to predict the longitudinal and transverse creep compliances, showing that the time dependencies were mainly governed by the PBT matrix. Given the minimal fiber orientation in the thickness direction, a transformation based on RM Jones’ mechanics of composite materials was applied to account for fiber misalignment. This led to the introduction of the unknown shear modulus G12, which was addressed by expressing it in terms of the transverse compliance J22 and shear correction factor. Comparison of predicted and measured creep compliances revealed an underestimation of 15–30% parallelly and 5–15% perpendicularly to the flow direction, attributed to imperfect fiber-matrix adhesion. SEM analysis of fracture surfaces indicated different failure behaviors based on the fiber orientation. This suggests that fiber-matrix adhesion is stress-direction dependent. The time range for accurate prediction of composite creep behavior, governed by matrix creep, is defined by the creep time limit, which decreases exponentially with increasing creep stress.CzechELib Transformative Agreemen
The role of socio-demographic characteristics on occupational outcomes: An empirical analysis of Pakistani labour market
Get PDFSocio-demographic characteristics play an important role in the occupational outcomes and influence the outlook of labour market. In general, studies are lacking to explore this phenomenon and particularly the context of Pakistan despite changing socio-demographic features of the country. Therefore, under the theoretical lens of demographic transition theory, the present study explores the role of socio-demographic characteristics on occupational outcomes in the labour market of Pakistan. Data of labour force survey for the year 2020–21, from Pakistan Bureau of Statistics (PBS), are analysed by using the multinomial logistic regression model. The study results show that education, training, age, gender, employment status, and living period in employed districts significantly affect the occupational choices in Pakistan. The participation of females in the labour market was found low as compared to males. In the case of marital status, unmarried have 0.68 times less probability relative to married to choose the manager’s occupation as compared to the elementary occupation. Age is 0.04 times likely the factor to choose agriculture, fishery, and forestry than the occupation elementary. Education appeared to be an important determinant for occupational choice. Theoretically, the study contributes by exploring overlooked aspect of socio-demographic characteristics in occupational outcomes. Practically, under the changing socio-demographic characteristics of Pakistan, the study has important implications towards the role of the government by enhancing the opportunities for free education in the country for better occupational outcomes as well as to devise policies to encourage females for their participation in the labour market of Pakistan.Open access publishing supported by the institutions participating in the CzechELib Transformative Agreement. This work was supported by the RVO project of the Faculty of Management and Economics, Tomas Bata University in Zlin under grant no. RO/FaME/2024/07.RVO project of the Faculty of Management and Economics, Tomas Bata University in Zlin [RO/FaME/2024/07
Comparison of hyperparameter tuning optimization methods for LSTM and stock price prediction
No full textThis paper investigates using Long Short-Term Memory (LSTM) networks for predicting stock prices, focusing on major stocks like AAPL, MSFT, TSLA, META, and GOOG from 2016 to 2021. We employ several technical analysis indicators, such as moving averages, the relative strength index, and others, as inputs to our LSTM model. The study involves data preprocessing, optimization, and tuning of ten different hyperparameters to enhance the performance of LSTM model. A comparative analysis of optimization techniques, including standard random search, Bayesian, Nevergrad optimization, covariance matrix adaptation optimization, and other bio-inspired algorithms, shows variations in performance across most datasets. Performance is measured using typical statistical metrics like mean squared error, R2 score, and others, with results showing varying prediction accuracies among different stocks. The study highlights the critical influence of data quality on LSTM performance and suggests further research into optimal hyperparameter tuning for enhancing AI-driven financial analytics.This work was supported by the Internal Grant Agency of the Tomas Bata University in Zlin, project number IGA/CebiaTech/2023/004, and further by resources of A.I.Lab (https://ailab.fai.utb.cz/). During the preparation of this work, the authors used OpenAI ChatGPT 4.0 in order to improve language and readability. After using this tool/service, the authors reviewed and edited the content as needed and take full responsibility for the content of the publication.Internal Grant Agency of the Tomas Bata University in Zlin [IGA/CebiaTech/2023/004
Modulating electronic structure to expedite Na4Fe3(PO4)2P2O7 reaction kinetics for high-power Na-ion batteries
No full textThe Na4Fe3(PO4)(2)P2O7 (NFPP) has considered as a very attractive cathode material for Na-ion batteries mainly due to its cheap price and high security. Its low electron transfer rate is usually improved by coating a layer of hard carbon, which however exhibits a low graphitization degree because of the relatively low NFPP synthesis temperature (~ 500 °C). In this study, a highly-conductive hybrid carbon has been employed to accelerate redox reaction kinetics of NFPP by modulating electronic structure for achieving high-power Na-ion batteries. The hybrid carbon is derived from the mixed polyethylene glycol (PEG) and glucose, in which the low ether bond energy (~ 340 kJ mol−1) of PEG facilitates the free radical generation during pyrolysis with high graphitization degree while glucose improves the uniformity of the carbon coating. As a result, the optimized cathode exhibits a very high reversible capacity of 90.8 mAh g−1 at 20C within 2.0–4.0 V with 85.3% capacity retention after 10,000 cycles, highlighting huge application potentials in two-wheeled electric vehicles, backup energy storage, and so forth.This study was financially supported by the National Natural Science Foundation of China (Nos. U22A20429 and 22308103), the Program for Shanghai Pilot Program for Basic Research (No. 22TQ1400100-13), and the Fundamental Research Funds for the Central Universities.National Natural Science Foundation of China [U22A20429, 22308103]; National Natural Science Foundation of China [22TQ1400100-13]; Program for Shanghai Pilot Program for Basic Research; Fundamental Research Funds for the Central Universitie