Current Issue : January-March Volume : 2026 Issue Number : 1 Articles : 5 Articles
The conventional dynamic fracture simulation by using the explicit algorithm often involves a large number of iteration computation due to the extremely small time interval. Thus, the most time-consuming process is the integration of constitutive relation. To improve the efficiency of the dynamic fracture simulation, a physics-informed neural network integration (PINNI) model is developed to calculate the integration of constitutive relation. PINNI employs a shallow multilayer perceptron with integrable activations to approximate constitutive integrand. To train PINNI, a large number of strains in a reasonable range are generated at first, and then the corresponding stresses are calculated by the mechanical constitutive relation. With the generated strains as input data and the calculated stresses as output data, the PINNI can be trained to reach a very high precision, whose relative error is about 7.8 × 10−5%. Next, the mechanical integration of constitutive relation is replaced by the well-trained PINNI to perform the dynamic fracture simulation. It is found that the simulation results by the mechanical and PINNI approach are almost the same. This suggests that it is feasible to use PINNI to replace the rigorous mechanical integration of constitutive relation. The computational efficiency is significantly enhanced, especially for the complicated constitutive relation. It provides a new AI-combined approach to dynamic fracture simulation....
Archard’s wear law is among the first and foremost wear models derived from contact mechanics that relates key operating conditions and material hardness to sliding wear through a multifaceted wear coefficient. This entry explores the development, generalization, and critique of the Archard model—a foundational model in wear prediction. It outlines the historical origins of the model, its basis in contact plasticity, and its use of a constant wear coefficient. The discussion highlights modern efforts to extend the model through variable exponents and empirical calibration. Key limitations such as the oversimplification of wear behavior, exclusion of factors like sliding velocity, and scale sensitivity are examined through both theoretical arguments and experimental evidence. The critiques reflect the model’s constrained applicability in diverse wear conditions across varied operating conditions and material phenomena....
Anthropogenic alterations of the land surface through activities such as agriculture, forestry and urban development represent important human-induced forcings on the Earth’s climate system. This study, conducted in the framework of the UpClim project, employs the nonhydrostatic WRF-ARW v4.5.1 model forced by ERA5 reanalysis data to assess the impact of land use changes (LUCs) on the European climate. The study aims to quantify the effects of LUCs over the EURO-CORDEX domain at 0.11◦ resolution during 1980–1985 by comparing simulations with transient land use forcing against a control run with static land use....
In a percolating system, there are typically exponentially many spanning paths. Here, we study numerically, for a two-dimensional L × L diluted system, restricted to percolating realizations, the number N of directed percolating paths. First, we study the average entropy S = log N as a function of the occupation density p and compare with mathematical results from the literature. Furthermore, we investigate the distribution P(S). By using large-deviation approaches, we are able to obtain P(S) down to the very low-probability tail reaching probabilities as small as 10−300. We consider the percolating phase, the (typically) non-percolating phase, and the critical point. Finally, we also analyze the structure of the realizations for some values of S and p....
Background: We present a multidisciplinary training experience based on simulation techniques and critical resource management implemented in the emergency department. Methods: Simulation courses/workshops were conducted with a multidisciplinary team from the Hospital Emergency Department. The timeline for their development includes a preliminary analysis of needs, objectives, and scenario design, development of the simulation course, and finally, areas of implementation. In this last phase, the teaching team prepares a document and/or report/summary of the activity in which, among other things, the aspects with the greatest capacity for improvement or the areas for implementation of safety measures are determined. A total of 112 healthcare professionals (doctors, nurses, and care assistants) participated in this training program. Its design consisted of the following stages: a preliminary analysis of training needs, the establishment of objectives and scenario design, the development of the simulation workshop, and finally, a report on areas for improvement in patient safety identified during the workshop learning process. Results: The workshops enabled us to identify areas for improvement and develop local protocols/recommendations aimed at improving patient safety in the emergency department, such as standardizing a protocol to guide us in managing resources in crisis situations, a protocol for airway management, a protocol for massive transfusion, and a review of the triage process. In addition, we added value by incorporating cognitive aids and visual tools into the standardization of processes. Conclusions: For resource management in this type of crisis in the hospital emergency setting, it is essential to use a debriefing process guided by experienced instructors after a specific experiential learning experience through simulation scenarios. This helps to contextualize and analyze the advantages and disadvantages of general recommendations....
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