Development Of High-fidelity Models Research Articles

Simulation and training for pediatric colorectal surgery and anorectal malformation: a scoping review.

To study the published literature for various models used for simulation and training in the field of pediatric colorectal surgery. A PubMed search was conducted for studies of simulation models in anorectal malformation on 24 March 2024 with the search words 'simulation pediatric colorectal surgery' followed by another search on 'simulation AND anorectal malformation' that gave 22 and 14 results, respectively (total 36). After removing 4 duplicate publications, 12 were found relevant to simulation and training in colorectal diseases. One publication relevant to the topic was added from literature, thirteen articles were studied. Of these, 5; 1; 4; and 3 were on inanimate models; animate model; 3D reconstructions; and training, respectively. Simulation models are available for posterior sagittal anorectoplasty. The same inanimate model was used in five articles. The animate model was based on a chicken cadaver. 3D models have been made for personalized preoperative assessment and to understand the imaging in anorectal malformation. One 3D model was made by regeneration of organoid epithelium. Training modules were made to evaluate surgical dissection, standardize surgical techniques, and improve proficiency. Simulation models are an important tool for teaching the steps of surgery and discussing the nuances of operative complications among mentors and peers. With advances in this field, the development of high-fidelity models, more training modules, and consensus on surgical techniques will benefit surgical training.

Investigation of the Influence of Data Collection and Analysis Procedures on Aerosol Filtration Model Development

Fibrous air filters are common devices used to remove airborne particles. Their performance is typically measured through their resistance to airflow and captured particle mass. Models describing the evolution of filter performance have been heavily researched; however, the need for improvement remains. Experimental work is irreplaceable in the development of high-fidelity models, yet the estimation of necessary variables is not trivial and may be influenced by selected measurement instruments and analysis methodologies. Therefore, the purpose of this work is to propose a framework to investigate the response of common aerosol measurement instruments, their corresponding analysis methodologies, and the application of their data. A Scanning Mobility Particle Sizer (SMPS) and Laser Aerosol Spectrometer (LAS) were selected for consideration, and their recorded data were compared against baseline measurements. The results of the experiments indicated that the SMPS and LAS yielded a ratio of estimated mass concentrations to the baseline mass concentrations of approximately 1.175 and 0.749, respectively. Regarding the SMPS, it was suggested that the measurable size range, application of a coverage factor, dynamic shape factor, and association between the curve fits and histograms were influential in the final estimates. For the LAS, the application of a curve fit, its association to the histograms, and the selection of the sampling periods were influential. Considering the results, the impact of these factors may not be considered negligible and may skew reproducibility between studies and fossilize confounding factors. Therefore, the proposed methodologies are useful in addressing potential errors in data collection and analysis.

A non-ideal solution theory for the mechanics and electrochemistry of charged membranes

Understanding how ions and solvent molecules migrate within charged membranes is fundamental for advancing the analysis of biological membranes and the design of energy storage and production devices. Recent efforts highlighted a significant interplay between mechanics and electrochemistry in charged membranes, calling for the development of high-fidelity models to describe their interaction. Here, we propose a continuum theory of the chemoelectromechanics of charged membranes, accounting for potentially large deformations and non-idealities of the solution permeating the membrane. We demonstrate the potential applications of our theory within the study of ionic polymer actuators. Our theory predicts sizeable effects of non-idealities and mechanical deformations, enabling insight into the role of mechanics on solute and solvent transport within charged membranes.

Bayesian updating and model class selection with Subset Simulation

Identifying the parameters of a model and rating competitive models based on measured data has been among the most important and challenging topics in modern science and engineering, with great potential of application in structural system identification, updating and development of high fidelity models. These problems in principle can be tackled using a Bayesian probabilistic approach, where the parameters to be identified are treated as uncertain and their inference information are given in terms of their posterior probability distribution. For complex models encountered in applications, efficient computational tools robust to the number of uncertain parameters in the problem are required for computing the posterior statistics, which can generally be formulated as a multi-dimensional integral over the space of the uncertain parameters. Subset Simulation has been developed for solving reliability problems involving complex systems and it is found to be robust to the number of uncertain parameters. An analogy has been recently established between a Bayesian updating problem and a reliability problem, which opens up the possibility of efficient solution by Subset Simulation. The formulation, called BUS (Bayesian Updating with Structural reliability methods), is based on the standard rejection principle. Its theoretical correctness and efficiency require the prudent choice of a multiplier, which has remained an open question. This paper presents a fundamental study of the multiplier and investigates its bias effect when it is not properly chosen. A revised formulation of BUS is proposed, which fundamentally resolves the problem such that Subset Simulation can be implemented without knowing the multiplier a priori. An automatic stopping condition is also provided. Examples are presented to illustrate the theory and applications.

Roll-to-roll 연속 공정을 위한 Multi-span Web 시스템의 횡방향 운동 해석

Based on the string, Euler beam, and Timoshenko beam theories, the transfer functions of axially translating web system to predict the lateral tracking are introduced in this paper. In addition, total transfer function of a multi-span web handling system is developed by the combination of the transfer functions of each single span. Experiments and computations are carried out and the results obtained for the Timoshenko beam model are compared with those of other models. The comparison indicates that the predictions from the Timoshenko and Euler beam models are quite different from that of the classical string model in both the gain and phase response. The results are expected to help in the development of high fidelity models of web tracking systems within a general computational framework.

Streamlining automotive product development using neural networks

To remain competitive in the global market, automotive companies scrutinise product development processes for time and cost savings incurred bringing new vehicles to market. As a result, virtual durability simulation can be utilised early in the design process to reduce the number of costly physical prototypes, assuming that high fidelity models are used. The compromise between model accuracy and computational efficiency presents a challenge that will be addressed by the authors. Neural networks, as computationally efficient mathematical models, will be shown as a viable tool for development of high fidelity models of nonlinear hysteretic components within a virtual durability simulation.