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Review of compensation topologies power converters coil structure and architectures for dynamic wireless charging system for electric vehicle
(MDPI, 2024) Rajamanickam, Narayanamoorthi; Shanmugam, Yuvaraja; Jayaraman, Rahulkumar; Petrov, Jan; Vávra, Lukáš; Goňo, Radomír
The increasing demand for wireless power transfer (WPT) systems for electric vehicles (EVs) has necessitated advancements in charging solutions, with a particular focus on speed and efficiency. However, power transfer efficiency is the major concern in static and dynamic wireless charging (DWC) design. Design consideration and improvements in all functional units are necessary for an increase in overall efficiency of the system. Recently, different research works have been presented regarding DWC at the power converter, coil structure and compensators. This paper provides a comprehensive review of power converters incorporating high-order compensation topologies, demonstrating their benefits in enhancing the DWC of EVs. The review also delves into the coupling coil structure and magnetic material architecture, pivotal in enhancing power transfer efficiency and capability. Moreover, the high-order compensation topologies used to effectively mitigate low-frequency ripple, improve voltage regulation, and facilitate a more compact and portable design are discussed. Furthermore, optimal coupling and different techniques to achieve maximum power transfer efficiency are discussed to boost magnetic interactions, thereby reducing power loss. Finally, this paper highlights the essential role of these components in developing efficient and reliable DWC systems for EVs, emphasizing their contribution to achieving high-power transfer efficiency and stability.
Three-stage pyrolysis-catalytic dry reforming of waste polyolefins over MFI and Ni-MFI catalysts for BTEX and syngas production
(Elsevier, 2024) Inayat, Amer; Inayat, Alexandra; Klemencová, Kateřina; Schwieger, Wilhelm; Leštinský, Pavel
This work presents an experimental proof-of-concept study for a three-stage pyrolysis-catalytic dry reforming process for recovering valuable chemicals from waste plastics. It is demonstrated that depending upon the catalysts, process parameters and reactor configuration, plastic waste and carbon dioxide can be converted into a diverse array of valuable chemicals which can be used as secondary feedstocks in the chemical or petrochemical industry, thus decreasing dependency on fossil resources and contributing to waste reduction. For this work, waste polypropylene was thermally pyrolyzed and the emerging vapors were passed over HZSM-5 catalyst to obtain BTEX-rich pyrolysis oil and pyrolysis gases containing mainly C1 to C4 hydrocarbons. The gaseous products were separated, mixed with CO2 and passed over Ni-silicalite-1 catalyst to obtain syngas, thus upgrading the pyrolysis gases and contributing to CO2 reduction. This study may provide new insights towards the development of processes for the chemical recycling of waste plastics and CO2.
The nexus of a regional competitiveness and economic resilience: The evidence-based on V4+4 NUTS 2 regions
(Technická univerzita v Liberci, 2024) Svoboda, Ondřej; Melecký, Lukáš; Staníčková, Michaela
Economies have always been prone to economic downturns, industry shocks, currency crises, and the current COVID-19 epidemic crises, destabilising a region's economic growth trajectory and pattern. By re-establishing economic ties both inside and outside regions, regional economies that have been disturbed by a shock may transition to a new growth trajectory. We examined the idea of competitiveness and resilience in a regional development context to answer why one region is more susceptible to economic shock than others and the competitive advantages and disadvantages of V4+4 countries. This article highlights some of the core characteristics of regional competitiveness and resilience and gives a survey of the notion, main empirical results, and planning tasks concerning regional competitiveness and resilience. The idea of resilience is gaining greatness because of the COVID-19 crisis, and its importance is growing in research and economic policymaking. Ideas like "2020 made us stronger" and "resilience, tenacity, and the ability has decreased the main systems' shock resistance and caused failures to spread from one system to another. Thus, it is necessary to suggest a systems approach focused on resilience to have socio-economic systems ready for potential shocks. The paper's main topic is resilience-focused its resilience considering the COVID-19 issue and the political agenda that is transition-driven in order to move forward or recover but emerge stronger. If policies are to be effective in the long run, an attitude responding to the systemic causes and impacts of big shocks is required.
A bibliometric review on application of machine learning in additive manufacturing and practical justification
(Elsevier, 2024) Ma, Quoc-Phu; Nguyen, Hoang-Sy; Hajnyš, Jiří; Měsíček, Jakub; Pagáč, Marek; Petrů, Jana
This paper delves into the cutting-edge applications of Machine Learning (ML) within modern Additive Manufacturing (AM), employing bibliometric analysis as its methodology. Formulated around three pivotal research questions, the study navigates through the current landscape of the research field. Utilizing data sourced from Web of Science, the paper conducts a comprehensive statistical and visual analysis to unveil underlying patterns within the existing literature. Each category of ML techniques is elucidated alongside its specific applications, providing researchers with a holistic overview of the research terrain and serving as a practical checklist for those seeking to address particular challenges. Culminating in a vision for the Smart Additive Manufacturing Factory (SAMF), the paper envisions seamless integration of reviewed ML techniques. Furthermore, it offers critical insights from a practical standpoint, thereby facilitating shaping future research directions in the field.
The effect of wood species on fine particle and gaseous emissions from a modern wood stove
(MDPI, 2024) Rinta-Kiikka, Henna; Dahal, Karna; Louhisalmi, Juho; Koponen, Hanna; Sippula, Olli; Krpec, Kamil; Tissari, Jarkko
Residential wood combustion (RWC) is a significant source of gaseous and particulate emissions causing adverse health and environmental effects. Several factors affect emissions, but the effects of the fuel wood species on emissions are currently not well understood. In this study, the Nordic wood species (named BirchA, BirchB, Spruce, SpruceDry, Pine and Alder) were combusted in a modern stove, and the emissions were studied. The lowest emissions were obtained from the combustion of BirchA and the highest from Spruce and Alder. The fine particle mass (PM2.5) was mainly composed of elemental carbon (50-70% of PM2.5), which is typical in modern appliances. The lowest PAH concentrations were measured from BirchA (total PAH 107 mu g/m3) and Pine (250 mu g/m3). In the ignition batch, the PAH concentration was about 4-fold (416 mu g/m3). The PAHs did not correlate with other organic compounds, and thus, volatile organic compounds (VOCs) or organic carbon (OC) concentrations cannot be used as an indicator of PAH emissions. Two birch species from different origins with a similar chemical composition but different density produced partially different emission profiles. This study indicates that emission differences may be due more to the physical properties of the wood and the combustion conditions than to the wood species themselves.