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This paper presents a comprehensive analysis of conical components in pressure vessels emphasizing their significance when utilized to transition between different diameters or slopes. A thorough design and analysis are underscored as essential for ensuring the safety and reliability of these components under diverse loading circumstances. The paper aims to propose enhancements to the European Pressure Vessel Standards concerning conical components under internal pressure, with a focus on improving safety, reliability, and compliance with industry standards. Existing European standards are reviewed, identifying potential gaps and proposing practical solutions. The paper also presents research findings on the influence of cone apex angles, shell geometries and design pressure on cone plate thickness calculations. A new methodology for the design and analysis of conical components in pressure vessels is proposed, offering a potential pathway to safer and more efficient pressure vessels. A range of cylinder diameter between 1000 and 2500 mm and cone angles between 30° and 60° are used as input to quantify the difference in cone thickness for a design pressure ranging between 10 and 200 bar g. The proposed method yields results much closer to AD2000 compared to EN13445, leading to slightly thicker cones (up to 2.2 mm for the selected range of cone diameters and angles) compared to the former, resulting in safer pressure vessel design, and thinner cones (up to 22 mm) compared to the latter resulting in significant material savings. A comparative analysis was performed through Finite Element Analysis validating the EN13445 unsuitability for cone thickness calculations. A modification is proposed for equation (7.6)-(8) in EN13445 resulting in thinner plates reducing the cone plate thickness difference to 0.9 % on average compared to the current deviation of -9.6 % on average for the selected range of cylinder diameters and cone angles. • Enhancements to European Pressure Vessel Standards focusing on conical components under internal pressure are proposed. • A comparative analysis between AD2000 and EN13445 on cone thickness and design safety is presented. • Theoretical calculations are validated through Finite Element Analysis, highlighting discrepancies and areas for improvement. • Modifications to EN13445 are suggested to better align the Standard with practical outcomes and reduce excess material. [ABSTRACT FROM AUTHOR]

• Novel insights into bolted connections to I-section webs and tubular column chords under out-of-plane loads via experimental testing. • Calibration of numerical models with experimental results for improved accuracy. • Extensive analysis of single and double bolt row connections in a parametric study to identify key parameters affecting face plate behavior. • Comparative analysis of existing methods for initial stiffness estimation using parametric analysis data, revealing their limitations. • Proposal of a refined analytical method for initial stiffness prediction, validated by experimental data. This paper presents a comprehensive investigation into the behavior of column webs/faces under out-of-plane loading within steel joints. The experimental component of the study involves testing five profiles, encompassing both open and closed sections with varying web slenderness and steel grade, subjected to direct out-of-plane tensile loads through bolted connections, utilizing both single and double rows of bolts. Concurrently, numerical simulations are conducted using finite element models, thoroughly calibrated with the experimental results. Drawing upon the calibrated numerical models, the paper systematically explores the influence of key parameters, including web slenderness, bolt arrangement, and analysis methods, through a parametric study involving 167 cases. A careful comparison of the observed behavior of the component from experimental tests, numerical models, and analytical models for initial stiffness is presented. Finally, the initial stiffness formulation derived from a recent model developed by the authors is improved to align with the observations from the experimental and numerical results. [ABSTRACT FROM AUTHOR]

Metastatic femoral tumors may lead to pathological fractures during daily activities. A CT-based finite element analysis of a patient's femurs was shown to assist orthopedic surgeons in making informed decisions about the risk of fracture and the need for a prophylactic fixation. Improving the accuracy of such analyses ruqires an automatic and accurate segmentation of the tumors and their automatic inclusion in the finite element model. We present herein a deep learning algorithm (nnU-Net) to automatically segment lytic tumors within the femur. A dataset consisting of fifty CT scans of patients with manually annotated femoral tumors was created. Forty of them, chosen randomly, were used for training the nnU-Net, while the remaining ten CT scans were used for testing. The deep learning model's performance was compared to two experienced radiologists. The proposed algorithm outperformed the current state-of-the-art solutions, achieving dice similarity scores of 0.67 and 0.68 on the test data when compared to two experienced radiologists, while the dice similarity score for inter-individual variability between the radiologists was 0.73. The automatic algorithm may segment lytic femoral tumors in CT scans as accurately as experienced radiologists with similar dice similarity scores. The influence of the realistic tumors inclusion in an autonomous finite element algorithm is presented in (Rachmil et al., "The Influence of Femoral Lytic Tumors Segmentation on Autonomous Finite Element Analyses", Clinical Biomechanics, 112, paper 106192, (2024)). • A deep learning algorithm for automatic segmentation of lytic femoral tumors is developed. • The deep learning dice similarity score of ∼0.67 is obtained, higher than any former study. • Inter-individual dice similarity score variability between two radiologists was 0.73. • The automatic segmentation of lytic tumors is as good as a radiologist. [ABSTRACT FROM AUTHOR]

• The finite element method is used to analyze complex grounding structures. • Measurements in operational grounding systems are used as reference. • Results from simulation, measurement, and calculation agree well. • The finite element method excels in low-frequency grounding structure analysis. • Analytical methods are insufficient for complex grounding systems. The safety of human beings and the integrity of electrical systems essentially depend on grounding systems. The main quality indicator of a grounding system is its resistance, measured after its implementation. During the design phase, it is essential to estimate this resistance, especially in complex structures. In this context, the Finite Element Method (FEM) is a highly effective numerical approach to estimating the resistance of the grounding system. This paper presents simulations using FEM for various types of complex grounding structures to determine their resistances. A variety of structures are subjected to simulations, and for reference purposes, the obtained results are compared with the resistance values obtained from operational grounding systems. Such analyses encompass structures employed in distribution, transmission, and substation systems. [ABSTRACT FROM AUTHOR]

In this paper, two variants of the magnetless dual rotor wound field excited flux switching generator (DRWFEFSG) are comparatively analyzed for single rotor wind turbine (termed as machine I (MI)) and counter rotating wind turbine applications (termed as machine II (MII)) for household direct current (DC) microgrid system. First, design concept and integration to wind turbine system are discussed. Secondly, comprehensively performance analysis i.e., static analysis, dynamic load/speed analysis and electromagnetic performance analysis are executed. Finite element analysis (FEA) based static analysis evident that MI offers 7.6% higher torque in inner rotor whereas MII exhibits 18% higher torque in outer rotor. Dynamic respond unveils that in comparison to MII, MI suffers from the issue of voltage regulation. Additionally, electromagnetic analysis reveals that both MI and MII exhibits excellent response under variable field Magneto-motive force (MMF). Comparative analysis unveils that MII requires lower field MMF to achieve same response to counterpart MI. Quantitative analysis divulge efficiency of 88.49% and power factor of 0.93 in MI whereas MII at rated operating point demonstrates 85.9% efficiency and 0.96 power factor. Finally, effectiveness of the study and validity of DRWFEFSG for wind turbine applications are tested with hardware prototypes of both MI and MII that fairly matched with FEA results. • Generator design and comparative analysis for household DC microgrid system. • Generator design for co-rotating and counter rotating wind turbine application. • Generator for rooftop wind turbine integrated with wind turbine. • Improve power wind turbines generators. • Analysis and comparative study of generator design for wind power generation. [ABSTRACT FROM AUTHOR]