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19th Youth Symposium on Experimental Solid Mechanics
No full textThe 19th Youth Symposium on Experimental Solid Mechanics was held in Rome, in June 5 - 7, 2024.
The 19th symposium continues both the long tradition of this conference series and introduces novel elements. The YSESM 2024 symposium provides a forum for young researchers and engineers, students and PhD students dealing with subjects of experimental mechanics. In addition, the combination of the experimental mechanics with modern numerical methods will be a new focus of this symposium.
The conference key topics were following:
Conventional and Advanced Experimental Methods in Solid and Fluid Mechanics
Non-Destructive Testing and Inspection
Measurements in Material Science
Computer Assisted Testing and Simulation
Engineering Design Simulation
Hybrid Methods, Experimental Techniques – Numerical Simulation
Optical Methods and Image Processing
Measurements in Biomechanics
Sensor Techniques for Micro- and Nano-Applications
Measurement Methods for Forensic Engineering
Scientific comittee:Lajos Borbás - Budapest University of Technology and EconomicsTomáš Doktor - Czech Technical University in PragueMarta Peña Fernández - Heriot-Watt UniversityDaniel Kytýř (chair) - Institute of Theoretical and Applied Mechanics, CASZoltán Major - Johannes Kepler University LinzGiangiacomo Minak - University of BolognaNejc Novak - University of MariborSascha Senck - Upper Austria University of Applied Sciences WelsJacek Tarasiuk - AGH University of Science and Technology in KrakówMatej Vesenjak - University of Maribor Zvonimir Tomičević - University of ZagrebPetr Zlámal - Institute of Theoretical and Applied Mechanics, CAS
Local organizing comittee:Riccardo Panciroli (chair)Giangiacomo MinakTiziano PagliaroliMaicol LaurenzaAndrea PagliaroDaniel KytýřPetr Zlámal
Guarantor of the peer review process:Daniel Kytýř
Guarantor of the language editing:Dalila El Oumal
Numerical simulation of vacuum arc under different axial magnetic fields and different erosion rates
Get PDFIn this paper, we present a three-dimensional (3D) numerical model that describes a high current vacuum arc in the subsonic regime between copper contacts under the influence of an axial magnetic field (AMF). The model is based on a MHD approach to the inter-electrode plasma and is realized with the commercial software Ansys Fluent. Only the plasma region is modelled. The behaviour of the copper electrodes is taken into account by specific boundary conditions. We describe the model, the boundary conditions and present the simulation results. Temperature profiles and electron and ion densities will be presented in a reference case. Based on this arc modelling, a parametric study on arc characteristics will be performed, including varying the AMF strength, the ablation rate and the current intensity
Reduction of torque pulsation in ultralight helicopter transmission
Get PDFUsually, 1–2 seats helicopters use piston engines. One of their disadvantages is a significant torque pulsation on the engine shaft. The main reason for such fluctuations is the change in parameters during the engine’s operating cycle. The purpose of the investigation was to define the pulsation on the helicopter rotor shaft. An additional elastic clutch was used on a single-seat ultralight helicopter Rotorschmiede VA-115 of German firm RS Helikopter GmbH for pulsation dampening. Several flights were performed to assess the pulsation on the shafts. The results of the tests showed that the torque pulsation on the shaft in all modes does not exceed 30 %. This is 10 times less than the pulsation value of 300% specified by the airworthiness standards for this helicopter class
Digital model of automated unmanned aerial vehicle with edge computing application for railway reconnaissance
Get PDFIn the last decade, unmanned aerial vehicles have been widely used in various civil and military field operations. Most modern drones are manually controlled by an operator and require decision making, which requires experience gained through training, which is time consuming and expensive, and even with experienced operators, the human factor can never be excluded. In this paper, an algorithm for an automatic flight mode of unmanned aerial vehicles without an operator’s participation has been developed. The proposed algorithm has been considered in the military reconnaissance of railways using edge computing and computer vision approaches to recognise railroads and moving trains for simulated and real cases as well as send report data to the web platform. As a result, the head of the operation received information about the number of carriages and Global Positioning System coordinates of the recognised train to make the necessary decisions
Landmark emancipation of technical intelligence in pre-World War II Czechoslovakia
Get PDFThis paper describes the development, activities, and both the scientific and social contributions of the Masaryk Academy of Labour, Czechoslovakia’s first technically oriented scientific institute and a major centre of the science at that time. It marked the first time an institution devoted to science and engineering had ever been established in the territory of what would eventually become the Czech Republic. Coming on the heels of Czechoslovakia’s independence at the end of the First World War, it succeeded the pre-war Royal Bohemian Society of Sciences and was integrated with the Czech Academy of Sciences and Arts and the newly established Czechoslovak National Council as the youngest of the Czech scientific institutions. In 1952, it was merged with other institutions to formthe Czechoslovak Academy of Sciences, the predecessor of today’s Czech Academy of Sciences. The significance of the Masaryk Academy of Labour lay mainly in its targeted, practical application of science and engineering
A geopolitics of the diaspora of British engineers in South America in the first half of the 20th century: the cases of the Institution of Locomotive Engineers centre in Argentina
Get PDFThe circulation of British engineers in South America during the first half of the twentieth century is a barely explored phenomenon that should be studied in the basis of methodologies that articulate the different elements involved, with the aim of contributing to the history of technology and providing new interpretations regarding the development and decline of the South American railway system. Through the case of the Institution of Locomotive Engineers centre in Argentina, the phenomenon of the diaspora of technical knowledge and technology transmission is examined
Reflections on the crisis management of selected municipal and city authorities during the coronavirus pandemic
Get PDFThe outbreak of the COVID-19 pandemic in the spring of 2020 had a significant impact on the operation of all aspects of society, including public administration institutions. This article aims to examine the most challenging issues encountered by selected municipal and city authorities, how they responded to these issues, and how the experience gained has been reflected in crisis plans for managing similar future events. This aim is accomplished through a literature review of public sources and scientific papers on the effects of the COVID-19 pandemic on public administration, as well as the results of interviews with representatives of the selected authorities. The results confirmed that the selected authorities were able to rapidly overcome the initial lack of relevant information and unpreparedness to implement anti-coronavirus measures and maintain the standard level of public services provided, albeit in a limited capacity
AI-enabled transition to smart European cities
Get PDFSmart cities continue to be discussed throughout Europe as a result of the continent’s rising urbanization and the need for sustainable development. Artificial intelligence (AI) has the potential to significantly promote this shift by assisting cities in becoming more effective, sustainable, and receptive to the requirements of their residents. The goal of this study is to examine the potential and difficulties of AI in urban development and present a framework for incorporating AI into city planning and management in European cities. This is done by analyzing case study examples from European cities and examining primary and secondary data sources, with the aim of providing a comprehensive framework for the sustainable integration of AI systems. This study presents a set of ethical and inclusive AI criteria, such as transparency, inclusion, and accountability, to enable responsible AI research and implementation. It continues by emphasizing the need for efficient AI integration in smart cities and pushing for a holistic AI-enabled transition to inclusive and sustainable smart cities
Analysis of concrete taken from a loaded column by determining the modulus of elasticity
Get PDFSustainability places an emphasis on preserving and using existing structures, particularly those that are historically or artistically valuable. The preservation of buildings is closely related to a good assessment of their condition. When making a diagnosis, it is suitable to use non-destructive methods to the greatest extent possible. However, these must also be complemented by core samples, which can be used to determine not only the compressive strength but also other important properties. The paper focuses on the evaluation of a reinforced concrete column that was gradually loaded until failure occurred. During loading, the quality of the concrete throughout the column was monitored using the ultrasonic pulse velocity method and, after loading was finished, the cores were taken from the column. The specimens, obtained from the core samples, were then carefully analysed using both non-destructive and destructive tests. The conclusion describes a possible approach to the assessment of concrete using a core examination
Dynamic behavior of a cable-stayed footbridge depending on the calculation accuracy
Get PDFFootbridges are analyzed in terms of dynamic response for pedestrian comfort. This problem is solved mainly on light and at the same time rigid constructions, which are easily oscillated by pedestrian load. It is often solved on steel footbridges, but with the technological development of UHPC, we are capable nowadays to build relatively light and long span concrete footbridges. Behaviour of a thin concrete cross-section with its geometry is closer to steel structures, but at the same time we have to deal with rheological effects such as creep and shrinkage. There are many influences on the structure that can affect the dynamic behavior of the structure, including the non-linear behavior of the cable system. This paper presents an initial entry into the computational issues of more complex constructions that have more input influences