KTU Open Journal Systems (Kaunas University of technology)
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MCrAlY Coating for High Temperature Oxidation Resistance of Engine Blade
No full textEngines have always been an important part of the development of the industrial field. With the continuous innovation of technology the requirements for the use of engines have become more stringent. In the current actual work of the engine, the import temperature has approached a thousand degrees, which makes the engine blades produce-temperature oxidation phenomenon under such harsh conditions, thus reducing their service performance. In order to improve the service life of engine blades under the current working environment, the technology MCrAlY coating with high-temperature oxidation resistance has become a hot spot for research at home and abroad, the arc ion plating coating preparation process has developed unprecedentedly and gradually become mature. Using GH4133 nickel-based high-temperature alloy material as the matrix, NiCrAlYSi coating was prepared and covered on its surface by using arc ion plating technology, and its thermal treatment was performed, and the anti-high-temperature oxidation performance of the coating was tested under a high-temperature environment, and the oxidation test was carried out for 192 hours continuously under a constant temperature of 1000℃, and the microstructure of the coating and the physical process of high-temperature oxidation were analyzed. The experiment shows: 1) the NiCrAlSi coating is smooth and flat, the cross section is clear and dense, there is no small hole defect, the coating is closely combined with the matrix; 2) after the thermal treatment, the surface particles of the NiCrAlYSi coating are more closely arranged, and the coating the matrix material become blurred due to mutual diffusion, but no obvious mutual diffusion layer is formed, through the analysis of XRD pattern, the NiCrAlYSi coating will significantly its anti-high temperature oxidation performance after the thermal treatment; 3) during the anti-high temperature oxidation process of the NiCrAlYSi coating, no peeling and holes appeared on the surface of the coating within 200 h, and the diffusion of elements occurred between the coating and the matrix, and then, the peeling holes gradually appeared on the surface of the coating, but due to the diffusion of elements, it made the coating matrix can still re-form the oxide protective layer, which prolonged the life of the high-temperature alloy
Investigation of Impact of Ceramic Nanomaterial Addition on Ductile Minerals: A Powder Metallurgy Approach
No full textThe addition of ceramic nanomaterials has a clear effect on minerals that suffer from ductility, when silica (SiO2) is incorporated into nickel metal (Ni) in volume ratios of 2 %, 4 %, 6 %, 8 %, and 10 %. The powder metallurgy process involved mixing designated volume ratios, the powders are milled for two hours using a custom electric mixer. Subsequently, the powder is placed into a press mold with a diameter of 10 mm, and the pressing operation is executed using a hydraulic press at a pressure of (80 MPa) for one minute. The resulting samples were heated at (1100 °C) for two hours. Some tests were conducted before and after the thermal sintering process, and the thermal treatments yielded significant experimental results, with the Brinell method showing the highest hardness at 770 kg/mm2 and the best compressive strength at 68 MPa. Additionally, the lowest porosity recorded was 9 %. Regarding the structural findings, the scanning electron microscopy (SEM) and X-ray diffraction provided clear results for the fabricated models in terms of how the structural elements were connected and dependent on each other, as well as the characteristics of the reinforcing material and its ability to permeate through the surface of the nickel base material
Microstructural Evolution and Corrosion Characteristics of Zn-RE-Mg-Al-Mn Cast Alloys
No full textIn this work, the effects of adding rare earth elements (Nd and Gd) and Mg, Al, and Mn on the microstructure and corrosion characteristics of Zn-based cast alloys were comprehensively studied. Eight different alloy samples were synthesized and analyzed by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), potentiodynamic polarization (Tafel) experiments, and immersion corrosion tests. Microstructural analysis revealed the presence of dendritic α-Zn phases in the Zn matrix and Nd-rich and Gd-rich intermetallic phases, whose morphology varied depending on the kind and quantity of the additives. The Tafel test values of corrosion potential (Ecorr) and current density (Icorr), and the immersion test-derived values of annual corrosion rates (mm/year), were well correlated with the degree of microstructural degradation. Sample Zn + 5 Mg + 0.1 Al + 0.01 Mn + 0.5 Nd + 2.0 Gd, which had the highest corrosion resistance with a higher percentage of Nd and more homogeneous in structure, followed by Sample Zn + 5 Mg + 0.1 Al + 0.01 Mn + 0.1 Nd with the poorest performance. Post-immersion SEM micrographs substantiated the corrosion and electrochemical as well as immersion results, and reiterated that the distribution of intermetallic phases, grain size, and homogeneity of alloying elements are the major parameters governing the corrosion behavior
Nedirbančio, nesimokančio ir mokymuose nedalyvaujančio jaunimo galimybių darbo rinkoje subjektyvus vertinimas
No full textStraipsnyje nagrinėjamas nedirbančio, nesimokančio ir mokymuose nedalyvaujančio jaunimo (18-35 metų amžiaus) subjektyvus galimybių darbo rinkoje vertinimas. Nuosekliai aptariami naujausi teoriniai diskursai ir empiriniai tyrimai NEET jaunimo tematika bei pristatomi 2023 m. Lietuvoje atlikto jaunimo gyvenimiškų galimybių sociologinio tyrimo (anketinės apklausos) rezultatai. Anketinės apklauso metu išryškėjo reikalingų savybių ir galimybių gauti tinkamą darbą subjektyvus vertinimas (N=161). Įsidarbinamumo galimybes riboja neatitikimas tarp individualių asmens savybių ir asmeninių aplinkybių (įsipareigojimai šeimai, sveikatos būklė). Beveik du trečdaliai apklaustųjų pritaria, kad profesinės kompetencijos kaip aukšta profesinė kvalifikacija yra svarbūs norint susirasti tinkamą darbą. Mokslinis tyrimas atliktas įgyvendinant Lietuvos mokslo tarybos finansuojamą mokslininkų grupių projektą ,,Lietuvos jaunimo gyvenimiškų galimybių diferenciacijos socioekonominiai veiksniai Lietuvoje“ (reg. Nr. S-MIP-22-42, sutarties data 2022-03-18).
Subjective Assessment of Labour Market Opportunities for Young People not in Employment, Education or Training
Abstract
This paper examines the subjective assessment of the labour market opportunities of young people (aged 18-35) who are not in employment, education or training in Lithuania. It consistently discusses the latest theoretical discourses and empirical research on NEET youth and presents the results of a sociological study (questionnaire survey) on youth life chances conducted in Lithuania in 2023. The results of the survey (N=161) revealed a subjective perspective on the necessary qualities and opportunities for employment. The study found that employment opportunities are often limited by a mismatch between individual characteristics and personal circumstances, such as family commitments or health conditions. Nearly two-thirds of respondents agree that professional competencies, such as high professional qualifications, are important for finding a suitable job. The research was carried out within the framework of the Lithuanian Research Council-funded research project "Socio-economic factors of differentiation of life chances of Lithuanian youth in Lithuania" (reg. no. S-MIP-22-42, contract date 2022-03-18)
Moralinės vaizduotės raiška COVID-19 valdymui skirtuose LR Seimo debatuose
No full textTyrimo aktualumas remiasi gausiai nagrinėjama, bet neišsemiama politikos bei moralės santykio filosofija. Pagrindinė tyrimo koncepcija – moralinė vaizduotė, kurią teoretikai sieja su dvejopais subjekto gebėjimais: gebėjimu įžvelgti moralinius situacijos aspektus (įžvalga) ir gebėjimu įsivaizduoti galimybių daugį (įžvalgų kiekis), t. y. alternatyvius probleminės situacijos sprendimus iš moralinės perspektyvos. Lyginant su sprendimų priėmimu verslo valdymo sektoriuje, kur moralinė vaizduotė empiriškai nagrinėta daugiau, politinės diskusijos ir svarstymai yra platesni savo tematikomis, o jiems įtakos turi didesnis ir įvairesnis veikėjų bei idėjų ratas. Tikslas – analizuojant per įžvalgos ir galimybių daugio numatymo komponentus atrasti politiniuose debatuose moralinės vaizduotės raišką ir jos sąlygas. Tyrimo empirinis pagrindas – su COVID-19 pandemijos valdymu susiję Seimo debatai. Tyrinėjama, kiek politikai geba įžvelgti moralinių klausimų, susijusių su nagrinėjama situacija, spektrą ir kiek plačios (ypač iš moralinės perspektyvos) yra galimų sprendimų, siūlymų išspręsti problemą, diskusijos, darant prielaidą, jog šie du moralinės vaizduotės apibrėžimais pagrįsti komponentai nusako moralinės vaizduotės kaip gebėjimo charakteristiką subjekto atžvilgiu. Tyrimo rezultatai rodo, kad politiniame diskurse galima aptikti (ir toliau tyrinėti) moralinės vaizduotės komponentus, naudojant turinio teminės analizės metodą. Taip pat tyrimas atskleidė, kad galėtų būti vertingas tolesnis moralinės vaizduotės ir ideologijos sąveikos tyrinėjimas.
The Manifestation of Moral Imagination in the Debates of the Seimas of the Republic of Lithuania on COVID-19 Management
Abstract
The relevance of the study is based on the widely studied, but inexhaustible philosophy of the relationship between politics and morality. The main concept of the study is moral imagination, which theorists associate with two abilities of the subject: the ability to see the moral aspects of a situation (insight) and the ability to imagine a multitude of possibilities (insight quantity), i.e. alternative solutions to a problematic situation from a moral perspective. Compared to decision-making in the business management sector, where moral imagination has been empirically studied more, political discussions and deliberations are broader in their topics, and they are influenced by a larger and more diverse circle of actors and ideas. The goal is to discover the manifestation of moral imagination in political debates and its conditions through the analysis of the components of insight and foresight of possibilities. The empirical basis of the study is the Seimas debates related to the management of the COVID-19 pandemic. The study examines the extent to which politicians are able to perceive the spectrum of moral issues related to the situation under consideration and how broad (especially from a moral perspective) the range of possible solutions, proposals for solving the problem, and discussions are, assuming that these two components based on definitions of moral imagination define the characteristics of the ability of moral imagination in relation to the subject. The results of the study show that it is possible to detect (and further study) components of moral imagination in political discourse using the thematic analysis of content. The study also revealed that further research into the bond between moral imagination and ideology could be valuable
Autonomy (or dependence) of the EU Economy on Critical Services in the Context of the New EU Industrial Policy and Economic Security
No full textThe paper addresses the following scientific problem: the autonomy (or dependence) of the EU industry on critical services in the context of reindustrialisation and economic security. Thus, this paper aims to capture the competitive position of critical services from both EU and non-EU origins within the European Single Market, in light of the New EU Industrial Policy and economic security. To this end we analysed 1) changes in rate of provision of critical services in the EU broken down by origin of providers; 2) a share of these services in total international service provision in the EU broken down by origin of providers; 3) competitive position of critical services and its changes in the EU market regarding the origin of the services providers; and finally, 4) competitive and trade positions of EU and non-EU critical services providers. Data on trade in services were obtained from the Eurostat International Trade in Services Database and are presented according to the Eurostat Balance of Payments Services Classification (EBOPS 2010). In order to identify the position of the EU and non-EU critical service providers to the European Union’s companies, we employ two specialisation measures commonly used in the trade literature - the Revealed Symmetric Comparative Advantage (RSCA) and the Trade Balance Index (TBI). The combination of the two indicators was visualised using the matrix proposed by Widodo adjusted to the aim of this research. In the first part of the paper, a literature review is presented, followed by a statistical analysis of trade and competitive positions of EU and non-EU critical services providers. The discussion, which is rather limited due to the small number of publications dealing with the problem raised, is presented. Finally, the paper ends with conclusions, policy recommendations and directions of further research. Our research allowed to state that the competitive position of critical services of EU providers is higher within the European Single Market in comparison to non-EU providers. This leads au to a conclusion that the EU maintains some level of autonomy in critical services and strengthened it over the last fifteen years (2010-2024)
Sustainability Values and Strategic Innovation in Sustainable Fashion MSMEs: the Dynamic Capabilities Perspective
No full textDespite the paradigmatic shift towards sustainable fashion, MSMEs are experiencing additional challenges when making efforts to integrate sustainability values in their innovations. To intensify the transition towards sustainable fashion, there is a need to strategically innovate for MSME. There is a research gap on how MSMEs could effectively select sustainability values and integrate them in strategic innovations with limited resources to gain commercial success and to successfully compete in the market. This research aims to reveal the essential sustainability-related values in MSMEs and the strategic innovation implementation applying the dynamic capabilities perspective. Based on an exploratory qualitative study of sustainable fashion enterprises in Lithuania, this research contributes to the strategic management literature by identifying microfoundations that allow sustainable fashion enterprises to develop dynamic capabilities, as well as to sustainable fashion literature by extracting sustainability values which can enable enterprises to pursue their goals more efficiently
Moving Toward Sustainable Finance: Leveraging Environment, Social and Governance (ESG) Performance and Risk Management to Drive Corporate Financing Efficiency
No full textThe growing demand for companies to adopt environmentally sustainable and ethical practices has led to a greater focus on the organization\u27s environmental, social, and governance accomsplishments. This study aims to investigate the relationship between environmental social and governance (ESG) and corporate financial risk (CFR) on corporate finance efficiency (CFE) in China, using a dataset of 400 Chinese firms registered on the Shanghai and Shenzhen A-share exchanges between 2013 and 2022, the analysis uses a data envelopment analysis (DEA) model with entity-fixed effects regression and a robustness test. The findings show a positive relationship between ESG and corporate finance efficiency, implying that promoting ESG practices can boost corporate financing efficiency. However, the study also found the negative effect of high financial risk on corporate financing efficiency. These findings have significant implications for businesses, investors, and policymakers. Businesses can enhance their long-term financial performance by giving ESG practices top priority and controlling financial risks. Policymakers can utilize these findings to encourage businesses to enhance their ESG practices and risk management to increase overall financing efficiency
Examining the Influence of Green HR Practices on Green Organizational Performance: Evidence from Pharmaceutical Sector of Asian Economies
No full textThe study investigates the relationship of green HR practices with green organizational performance. This paper further analyzes the impact of different dimensions: green performance management, green HR data and analytics, green recruitment and selection, green compensation and evaluation, green succession planning, green training and development, and green HR information systems on green HR practices. This paper examines the mediation of green HR purchasing and environment and eco-design and internal management between green HR practices and organizational performance. The researchers used structured and modified questionnaires and collected 465 responses from the pharmaceutical sector of Asian economies such as China, India, Pakistan, South Korea, and Japan. The researchers employed PLS-SEM modeling using Smart-PLS 4.0 software to analyze the data. The findings of this research demonstrate that green HR practices have a significant and affirmative relationship with green organizational performance. Results further indicate that green performance management, green HR data and analytics, green recruitment and selection, green compensation and evaluation, green succession planning, green training and development, and green HR information systems positively and significantly impact green HR practices. Finally, the findings show that green HR purchasing, environment, eco-design, and internal management significantly mediate between green HR practices and organizational performance. The study\u27s findings have demonstrated a significant theoretical and managerial implication for researchers, academicians, industry practitioners, and policymakers. Moreover, the findings of this study also provide the roadmap to attain one of the most important goals of the sustainable development goals (SDGs) of the United Nations (UN): eco-friendly sustainability
Contribution of Bio-Based Buildings Made with Seaweed and Seagrass in the Construction Industry. A Bibliographic review
No full textDue to the construction industry, the climate crisis had deepest environmental impact. In addition to consuming scarce mineral-based materials, the building industry is responsible for up to 39% of global carbon dioxide emissions and the accumulation of solid waste in landfills, rivers, and seas. To cut carbon dioxide emissions and mitigate the effects of climate change on the construction industry, a new, more sustainable, and renewable production matrix must be considered. An approach is using seaweed and seagrass as bio-based materials matrix, from macroalgae or microalgae stranded on the shore or sustainable crops. Transforming algae into usable construction materials involves a process of harvesting, processing, and refining. This article has systematically reviewed the literature about advances and the potential of using marine species as construction materials matrix. To this end, this paper explores the existing literature on architectural projects and research on various species of seagrass and seaweed worldwide.
This review concludes that numerous case studies of dwellings around the world have demonstrated and validated the use of seaweed for applications such as coatings, thermal insulation, and construction additives. Among the most important construction related properties of seaweed are fire resistance, low thermal conductivity, and resistance to moisture and insect damage. For instance, prototypes incorporating Neptune grass (Posidonia oceanica) exhibited a thermal conductivity of 0.044 W/m·K comparable to that of expanded polystyrene, which typically ranges between 0.035 and 0.037 W/m·K.
The availability of seaweed, considered the waste that pollutes an essential part of the world\u27s coastline, is increasing every year. Nevertheless, not all types of seaweed can be used as construction materials. For this reason, there are some challenges in creating sustainable cultivation of seaweed species, like the need for efficient methods, harvesting, and its processing. In consequence, these costs must be incorporated into the selling price. However, these difficulties do not diminish the seaweed and seagrass\u27s potential as a renewable substitute in the production matrix of the construction industry. These challenges must be overcome before the industrial use of marine species as building materials becomes a reality. Governments must provide financial support to get these initiatives off the ground, especially in the crucial pre-competitive phases. At the same time, the development of prefabrication systems is of vital importance. These systems will enable certification and compliance with building materials regulations and pave the way for a more sustainable future for the industry. It is also necessary to establish seaweed and seagrass cultivation methods that will make the initiative sustainable in the long term, incorporating the costs associated with cultivation, harvesting, and processing into the selling price